Murdoch Retreats from China

Institute of Scientific and Technical Information of China (English)

Jessy Zhang

2006-01-01

@@ News Corp's Asian flagship enterprise Star Group announced in early June it would sell a 19.9 percent stake in Phoenix Satellite Television to China Mobile. This move is widely interpreted as a signal that Rudolf Murdoch, the helmsman of News Corp,might have lost his patience and could eventually retreat from the Chinese media market.

Wastewater retreatment and reuse system for agricultural irrigation in rural villages.

Science.gov (United States)

Kim, Minyoung; Lee, Hyejin; Kim, Minkyeong; Kang, Donghyeon; Kim, Dongeok; Kim, YoungJin; Lee, Sangbong

2014-01-01

Climate changes and continuous population growth increase water demands that will not be met by traditional water resources, like surface and ground water. To handle increased water demand, treated municipal wastewater is offered to farmers for agricultural irrigation. This study aimed to enhance the effluent quality from worn-out sewage treatment facilities in rural villages, retreat effluent to meet water quality criteria for irrigation, and assess any health-related and environmental impacts from using retreated wastewater irrigation on crops and in soil. We developed the compact wastewater retreatment and reuse system (WRRS), equipped with filters, ultraviolet light, and bubble elements. A pilot greenhouse experiment was conducted to evaluate lettuce growth patterns and quantify the heavy metal concentration and pathogenic microorganisms on lettuce and in soil after irrigating with tap water, treated wastewater, and WRRS retreated wastewater. The purification performance of each WRRS component was also assessed. The study findings revealed that existing worn-out sewage treatment facilities in rural villages could meet the water quality criteria for treated effluent and also reuse retreated wastewater for crop growth and other miscellaneous agricultural purposes.

Patients' perceptions, treatment need, and complexity of orthodontic re-treatment

NARCIS (Netherlands)

Ren, Yijin; Boxum, Christo; Sandham, John

The aim of the present study was to investigate the subjective perception and objective treatment need and complexity of patients seeking orthodontic re-treatment. One hundred subjects (66 females, 34 males, age 26.7+/-8.2 years) seeking re-treatment were asked to complete a questionnaire which was

Risk factors for tuberculosis treatment failure, default, or relapse and outcomes of retreatment in Morocco.

Science.gov (United States)

Dooley, Kelly E; Lahlou, Ouafae; Ghali, Iraqi; Knudsen, Janine; Elmessaoudi, My Driss; Cherkaoui, Imad; El Aouad, Rajae

2011-02-28

Patients with tuberculosis require retreatment if they fail or default from initial treatment or if they relapse following initial treatment success. Outcomes among patients receiving a standard World Health Organization Category II retreatment regimen are suboptimal, resulting in increased risk of morbidity, drug resistance, and transmission.. In this study, we evaluated the risk factors for initial treatment failure, default, or early relapse leading to the need for tuberculosis retreatment in Morocco. We also assessed retreatment outcomes and drug susceptibility testing use for retreatment patients in urban centers in Morocco, where tuberculosis incidence is stubbornly high. Patients with smear- or culture-positive pulmonary tuberculosis presenting for retreatment were identified using clinic registries in nine urban public clinics in Morocco. Demographic and outcomes data were collected from clinical charts and reference laboratories. To identify factors that had put these individuals at risk for failure, default, or early relapse in the first place, initial treatment records were also abstracted (if retreatment began within two years of initial treatment), and patient characteristics were compared with controls who successfully completed initial treatment without early relapse. 291 patients presenting for retreatment were included; 93% received a standard Category II regimen. Retreatment was successful in 74% of relapse patients, 48% of failure patients, and 41% of default patients. 25% of retreatment patients defaulted, higher than previous estimates. Retreatment failure was most common among patients who had failed initial treatment (24%), and default from retreatment was most frequent among patients with initial treatment default (57%). Drug susceptibility testing was performed in only 10% of retreatment patients. Independent risk factors for failure, default, or early relapse after initial treatment included male gender (aOR = 2.29, 95% CI 1

Incidence, outcomes, and risk factors for retreatment after wavefront-optimized ablations with PRK and LASIK.

Science.gov (United States)

Randleman, J Bradley; White, Alfred J; Lynn, Michael J; Hu, Michelle H; Stulting, R Doyle

2009-03-01

To analyze and compare retreatment rates after wavefront-optimized photorefractive keratectomy (PRK) and LASIK and determine risk factors for retreatment. A retrospective chart review was performed to identify patients undergoing PRK or LASIK with the wavefront-optimized WaveLight platform from January 2005 through December 2006 targeted for a piano outcome and to determine the rate and risk factors for retreatment surgery in this population. Eight hundred fifty-five eyes were analyzed, including 70 (8.2%) eyes with hyperopic refractions and 785 (91.8%) eyes with myopic refractions. After initial treatment, 72% of eyes were 20/20 or better and 99.5% were 20/40 or better. To improve uncorrected visual acuity, 54 (6.3%) eyes had retreatments performed. No significant differences in retreatment rates were noted based on age (P = .15), sex (P = .8), eye (P = .3), PRK versus LASIK (P = 1.0), room temperature (P = .1) or humidity (P = .9), and no correlation between retreatment rate and month or season of primary surgery (P = .4). There was no correlation between degree of myopia and retreatment rate. Eyes were significantly more likely to undergo retreatment if they were hyperopic (12.8% vs 6.0%, P = .006) or had astigmatism > or = 1.00 diopter (D) (9.1% vs 5.3%, P = .04). Retreatment rate was 6.3% with the WaveLight ALLEGRETTO WAVE excimer laser. This rate was not influenced by age, sex, corneal characteristics, or environmental factors. Eyes with hyperopic refractions or astigmatism > or = 1.00 D were more likely to undergo retreatment.

Modeling Antarctic Ice Sheet retreat in warm climates: a historical perspective.

Science.gov (United States)

Pollard, D.; Deconto, R. M.; Gasson, E.

2016-12-01

Early modeling of Antarctic Ice Sheet size vs. climate focused on asymmetry between retreat and growth, with much greater warming needed to cause retreat from full ice cover, due to Height Mass Balance Feedback and albedo feedback. This led to a long-standing model-data conflict, with models needing 1000 to2000 ppmv atmospheric CO2 to produce retreat from full size, vs. proxy data of large ice fluctuations despite much lower CO2 since the Miocene.Subsequent modeling with marine ice physics found that the West Antarctic Ice Sheet could undergo repeated warm-period collapses with realistic past forcing. However, that yields only 3 to 7 m equivalent sea-level rise above modern, compared to 10 to 20 m or more suggested by some geologic data. Large subglacial basins in East Antarctica could be vulnerable to the same processes,but did not retreat in most models due to narrower and shallower sills.After recent modifications, some ice sheet models were able to produce warm-period collapse of major East Antarctic basins, with sea-level rise of up to 15 m. The modifications are (i) hydrofracturing by surface melt, and structural failure of ice cliffs, or (ii) numerical treatment at the grounding line. In these models, large retreat occurs both for past warmintervals, and also for future business-as-usual scenarios.Some interpretations of data in the late Oligocene and Miocene suggest yet larger fluctuations, between 50 to 100% of modern Antarctic size. That would require surface-melt driven retreat of some terrestrial East Antarctic ice, despite the hysteresis issue raised above. A recent study using a coupled climate-ice sheet model found that with a finer climate gridand more frequent coupling exchange, substantial retreat of terrestrial Antarctica can occur with 500 to 840 ppmv CO2, much lower than in earlier models. This will allow meaningful interactions between modeling and deeper-time geologic interpretations since the late Oligocene.

Enhancing the research and publication efforts of health sciences librarians via an academic writing retreat.

Science.gov (United States)

Bullion, John W; Brower, Stewart M

2017-10-01

This case study describes the South Central Chapter of the Medical Library Association (SCC/MLA) initiative to develop an academic writing retreat for members who sought the necessary time and support to advance their research projects toward publication. SCC/MLA staged a dedicated writing retreat to coincide with the organization's 2012, 2013, and 2014 annual meetings. Each cohort met over two days to write and to workshop their peers' manuscripts. Organizers distributed an online survey one month after each retreat to evaluate attendees' perceptions. Three years' worth of writing retreats yielded fourteen peer-reviewed articles and one book chapter. Participants indicated that the retreat helped them meet or exceed their writing goals by offering protected time and a setting conducive to productivity. The format of the retreat is cost effective and easily adaptable for fellow professionals who wish to organize a formal event as a conference offering or simply support a writing group at their home institutions. In SCC/MLA, the retreat revitalized interest in writing and demystified the scholarly publication process.

Reliable Refuge: Two Sky Island Scorpion Species Select Larger, Thermally Stable Retreat Sites.

Science.gov (United States)

Becker, Jamie E; Brown, Christopher A

2016-01-01

Sky island scorpions shelter under rocks and other surface debris, but, as with other scorpions, it is unclear whether these species select retreat sites randomly. Furthermore, little is known about the thermal preferences of scorpions, and no research has been done to identify whether reproductive condition might influence retreat site selection. The objectives were to (1) identify physical or thermal characteristics for retreat sites occupied by two sky island scorpions (Vaejovis cashi Graham 2007 and V. electrum Hughes 2011) and those not occupied; (2) determine whether retreat site selection differs between the two study species; and (3) identify whether thermal selection differs between species and between gravid and non-gravid females of the same species. Within each scorpion's habitat, maximum dimensions of rocks along a transect line were measured and compared to occupied rocks to determine whether retreat site selection occurred randomly. Temperature loggers were placed under a subset of occupied and unoccupied rocks for 48 hours to compare the thermal characteristics of these rocks. Thermal gradient trials were conducted before parturition and after dispersal of young in order to identify whether gravidity influences thermal preference. Vaejovis cashi and V. electrum both selected larger retreat sites that had more stable thermal profiles. Neither species appeared to have thermal preferences influenced by reproductive condition. However, while thermal selection did not differ among non-gravid individuals, gravid V. electrum selected warmer temperatures than its gravid congener. Sky island scorpions appear to select large retreat sites to maintain thermal stability, although biotic factors (e.g., competition) could also be involved in this choice. Future studies should focus on identifying the various biotic or abiotic factors that could influence retreat site selection in scorpions, as well as determining whether reproductive condition affects thermal

Scientific retreats with 'speed dating': networking to stimulate new interdisciplinary translational research collaborations and team science.

Science.gov (United States)

Ranwala, Damayanthi; Alberg, Anthony J; Brady, Kathleen T; Obeid, Jihad S; Davis, Randal; Halushka, Perry V

2017-02-01

To stimulate the formation of new interdisciplinary translational research teams and innovative pilot projects, the South Carolina Clinical and Translational Research (SCTR) Institute (South Carolina Clinical and Translational Science Award, CTSA) initiated biannual scientific retreats with 'speed dating' networking sessions. Retreat themes were prioritized based on the following criteria; cross-cutting topic, unmet medical need, generation of novel technologies and methodologies. Each retreat begins with an external keynote speaker followed by a series of brief research presentations by local researchers focused on the retreat theme, articulating potential areas for new collaborations. After each session of presentations, there is a 30 min scientific 'speed dating' period during which the presenters meet with interested attendees to exchange ideas and discuss collaborations. Retreat attendees are eligible to compete for pilot project funds on the topic of the retreat theme. The 10 retreats held have had a total of 1004 participants, resulted in 61 pilot projects with new interdisciplinary teams, and 14 funded projects. The retreat format has been a successful mechanism to stimulate novel interdisciplinary research teams and innovative translational research projects. Future retreats will continue to target topics of cross-cutting importance to biomedical and public health research. Copyright © 2016 American Federation for Medical Research.

Little Ice Age advance and retreat of Glaciar Jorge Montt, Chilean Patagonia

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A. Rivera

2012-03-01

Full Text Available Glaciar Jorge Montt (48°20' S/73°30' W, one of the main tidewater glaciers of the Southern Patagonian Icefield (SPI, has experienced the greatest terminal retreat observed in Patagonia during the past century, with a recession of 19.5 km between 1898 and 2011. This retreat has revealed trees laying subglacially until 2003. These trees were dated using radiocarbon, yielding burial ages between 460 and 250 cal yrs BP. The presence of old growth forest during those dates indicates that Glaciar Jorge Montt was upvalley of its present position before the commonly recognized Little Ice Age (LIA period in Patagonia. The post-LIA retreat was most likely triggered by climatically induced changes during the 20th century; however, Glaciar Jorge Montt has responded more dramatically than its neighbours. The retreat of Jorge Montt opened a 19.5 km long fjord since 1898, which reaches depths in excess of 390 m. The bathymetry is well correlated with glacier retreat rates, suggesting that dynamic responses of the glacier are at least partially connected to near buoyancy conditions at the ice front, resulting in high calving fluxes, accelerating thinning rates and rapid ice velocities.

Scientific Retreats with ‘Speed Dating’: Networking to Stimulate New Interdisciplinary Translational Research Collaborations and Team Science

Science.gov (United States)

Alberg, Anthony J.; Brady, Kathleen T.; Obeid, Jihad S.; Davis, Randal; Halushka, Perry V.

2016-01-01

To stimulate the formation of new interdisciplinary translational research teams and innovative pilot projects, the South Carolina Clinical & Translational Research (SCTR) Institute (South Carolina Clinical and Translational Science Award, CTSA) initiated biannual scientific retreats with “speed dating” networking sessions. Retreat themes were prioritized based on the following criteria; cross-cutting topic, unmet medical need, generation of novel technologies and methodologies. Each retreat commences with an external keynote speaker followed by a series of brief research presentations by local researchers focused on the retreat theme, articulating potential areas for new collaborations. After each session of presentations, there is a 30 minute scientific “speed dating” period during which the presenters meet with interested attendees to exchange ideas and discuss collaborations. Retreat attendees are eligible to compete for pilot project funds on the topic of the retreat theme. The 10 retreats held have had a total of 1004 participants, resulted in 61 pilot projects with new interdisciplinary teams, and 14 funded projects. The retreat format has been a successful mechanism to stimulate novel interdisciplinary research teams and innovative translational research projects. Future retreats will continue to target topics of cross-cutting importance to biomedical and public health research. PMID:27807146

Retreatment of Exudative Age-Related Macular Degeneration after Loading 3-Monthly Intravitreal Ranibizumab.

Science.gov (United States)

Sugiyama, Atsushi; Sakurada, Yoichi; Honda, Shigeru; Miki, Akiko; Matsumiya, Wataru; Yoneyama, Seigo; Kikushima, Wataru; Iijima, Hiroyuki

2018-01-01

The aim of this study was to investigate the clinical implications of required retreatment after 3-monthly intravitreal ranibizumab (IVR) injections followed by as-needed reinjections up to 5 years in eyes with exudative age-related macular degeneration (AMD). A retrospective cohort study was conducted for 165 treatment-naïve eyes from 165 patients with exudative AMD. Visual changes were investigated in terms of the required retreatments. Retreatment-free proportions were 37.0, 23.7, 16.6, 12.1, and 10.5% at 12, 24, 36, 48, and 60 months, respectively. Visual changes were significantly better in eyes which did not require retreatment at every yearly checkpoint within the 5 years. A multivariate logistic regression analysis revealed that requirement of additional IVR treatments in the first 12-24 months was associated with the T allele (risk allele) of ARMS2 A69S (p = 0.010 and 0.015, respectively). Cox regression analysis revealed that older age (p = 0.046) and the T allele of ARMS2 A69S (p = 0.036) were associated with required retreatment within the 5-year follow-up period. Age and the T allele of ARMS2 A69S are the risk factors requiring retreatments, leading to poor visual change in eyes with exudative AMD following the initial 3-monthly IVR. © 2017 S. Karger AG, Basel.

A century of ice retreat on Kilimanjaro: the mapping reloaded

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N. J. Cullen

2013-03-01

Full Text Available A new and consistent time series of glacier retreat on Kilimanjaro over the last century has been established by re-interpreting two historical maps and processing nine satellite images, which removes uncertainty about the location and extent of past and present ice bodies. Three-dimensional visualization techniques were used in conjunction with aerial and ground-based photography to facilitate the interpretation of ice boundaries over eight epochs between 1912 and 2011. The glaciers have retreated from their former extent of 11.40 km2 in 1912 to 1.76 km2 in 2011, which represents a total loss of about 85% of the ice cover over the last 100 yr. The total loss of ice cover is in broad agreement with previous estimates, but to further characterize the spatial and temporal variability of glacier retreat a cluster analysis using topographical information (elevation, slope and aspect was performed to segment the ice cover as observed in 1912, which resulted in three glacier zones being identified. Linear extrapolation of the retreat in each of the three identified glacier assemblages implies the ice cover on the western slopes of Kilimanjaro will be gone before 2020, while the remaining ice bodies on the plateau and southern slopes will most likely disappear by 2040. It is highly unlikely that any body of ice will be present on Kilimanjaro after 2060 if present-day climatological conditions are maintained. Importantly, the geo-statistical approach developed in this study provides us with an additional tool to characterize the physical processes governing glacier retreat on Kilimanjaro. It remains clear that, to use glacier response to unravel past climatic conditions on Kilimanjaro, the transition from growth to decay of the plateau glaciers must be further resolved, in particular the mechanisms responsible for vertical cliff development.

Continuing evidence for poorer treatment outcomes for single male patients: Retreatment data from RTOG 97-14

International Nuclear Information System (INIS)

Konski, Andre; DeSilvio, Michelle; Hartsell, William; Watkins-Bruner, Deborah; Coyne, James; Scarantino, Charles; JanJan, Nora

2006-01-01

Purpose: The specific aim of this study was to evaluate outcome differences by gender and partner status for patients treated on Radiation Therapy Oncology Group (RTOG) protocol 97-14. Methods and Materials: RTOG 97-14 randomized patients with metastatic breast or prostate cancer to bone to receive 8 Gy in 1 fraction or 30 Gy in 10 fractions. Retreatment rates and overall survival were made based upon gender, marital status, and Karnofsky Performance Status (KPS). The cumulative incidence method was used to estimate retreatment time at 36 months from enrollment, and Gray's test was used to test for treatment differences within the same groupings. Marital status, gender, KPS, and treatment were variables tested in a univariate Cox model evaluating the time to retreatment. Results: Married men and women and single women receiving 30 Gy had significantly longer time to retreatment, p = 0.0067, p = 0.0052, and p = 0.0009 respectively. We failed to show a difference in retreatment rates over time in single men receiving either 30 Gy or 8 Gy. Univariate analysis of the entire group determined patients receiving 30 Gy in 10 fractions significantly less likely to receive retreatment, p < 0.0001, with a trend toward single patients less likely to be re-treated, p = 0.07. Conclusion: Non-disease-related variables, such as social support, might influence the results of clinical trials with subjective endpoints such as retreatment rates. The statistically nonsignificant difference in the 36-month retreatment rates observed in single male patients receiving 8 Gy may be a result of inadequate social support systems in place to facilitate additional care. Patients receiving 8 Gy in a single fraction had significantly higher retreatment rates compared with patients receiving 30 Gy in 10 fractions

The Role of Silence at the Retreats of a Buddhist Community

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Orsolya Huszár

2016-12-01

Full Text Available The purpose of the study is to establish that the definition of silence as simply an absence of something or as the background of communication proves to be inadequate in a number of communicative instances. The interpretation of silence is culturally determined, and the underappreciation of its role is typical in low-context Western cultures; this is also evinced by the neglect of the topic in the literature. The present study will describe the communicative functions of silence through the findings of field work conducted at the retreats of a Buddhist community in Hungary, providing empirical input for the relevant theoretical constructs. The research findings show that silence is accorded a central role in essentially every component of the retreat (meditations, relaxation, ceremonies, teachings, small-group sharings, meals and rest; and while each event at the retreat focuses primarily on a different specific function of communication, the entire retreat does involve the linkage, affecting, revelational and – to a certain extent – activating functions (to follow the five-element typology of J. Vernon Jensen, as well as – to a lesser extent – the judgmental function. The research also shows that it requires time for individuals in a low-context culture to recognize the “point” of silence – something that the retreats provide the right opportunity for. In fact, the insights the individuals arrived at through these occasions could be put to use in their daily lives, helping their problem-solving and social relationships and in general improving their quality of life.

Transcending Gender: Female Non-Buddhists’ Experiences of the Vipassanā Meditation Retreat

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Brooke Schedneck

2018-03-01

Full Text Available Female non-Buddhists have been writing detailed descriptions of their personal experiences in vipassanā meditation retreats since the 1960s. These memoirists relate to the English-speaking world their experience of the retreat process and self-transformations. Early memoirists traveled Asia in order to learn and practice vipassanā meditation. These memoirs are as much about the meditation practice itself as living in an Asian culture. The mindfulness craze, beginning in the late 2000s, brought with it increased awareness of vipassanā practice. At this time we see a renewed interest in recording vipassanā retreat experiences, but these are even more personal and not concerned with travel, as many vipassanā meditation retreats are now available outside of Asia. I consider four female memoirists: Marie Byles and Jane Hamilton-Smith, writing in the 1960s and 1970s, and Raji Lukkoor, and Jennifer Howd, whose memoirs appeared in 2010 and 2014, respectively. These women’s writings demonstrate that, although non-Buddhist female meditators understand vipassanā meditation as a nongendered practice, it is still an embodied, gendered experience. Each of these women has different reactions to the female gender on the retreat, from outrage at gender discrimination to acceptance of it, from judgment of female teachers and meditators to revealing a more feminine self.

Assessment of Apical Extrusion of Debris during Endodontic Retreatment with 3 Rotary Nickel-Titanium Retreatment Systems and Hand Files

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Gkampesi S.

2016-03-01

Full Text Available Aim: to evaluate the amount of debris extruded apically as well as the time needed for removal of root canal filling material using ProTaper, MTwo, REndo NiTi rotary retreatment systems and hand files.

Extreme beach retreat history inferred from cut-and-fill beach deposits at Moruya, SE Australia

Science.gov (United States)

Tamura, T.; Woodroffe, C. D.; Oliver, T.; Cunningham, A. C.

2017-12-01

A sequence of beach ridges often records a `cut and fill', where the fair-weather swash accretion of beach sand is punctuated by storm erosion. The detailed chronology of the sequence is thus a clue to decipher past storm events and associated beach erosion, but has not been explored much. Here we explore the potential of such a sequence to detect past extreme retreats in Bengello Beach at Moruya, southeastern Australia. Beach monitoring since 1972 reveals that Bengello beach has shown a typical cut and fill, in which the beach retreats several tens of meters in relation to storms and recovers within a following few years. A storm event caused extreme retreat up to 50 m in 1974. Since then, no retreat exceeded 30 m. The beach monitoring highlights the sporadic nature of the prograded beach deposits; they can only be preserved as stratigraphic records during rapid beach recovery following a large retreat deeper than the beach profile envelope. Thus, ages of the preserved beach deposits roughly correspond to timings of large retreat. Optically-stimulated luminescence (OSL) ages were determined for beach deposits at 5-10 m intervals along a shore-normal transect from the modern foredune to beach ridge 120 m inland. The most landward sample was dated as 510 yr, indicating that the net progradation rate is 0.24 m/yr, concordant with both the long- and short-term rates since the mid Holocene and 1972, respectively. Other ages show four events of retreat around 350, 180, 130 and 90 yr, and also reflect the beach scarp resulting from the 1974 event. The retreat of each event is given by the distance between the shoreline position prior to storm erosion and relevant gap in OSL age. The position of the pre-storm shoreline is estimated by assuming a constant rate of the net progradation of 0.24 m/yr, as with long- and short-term rates. The retreat of the four events is then determined as 45-55 m, similar to the 1974 event. In summary, extreme beach retreats, including that in

Spiral computed tomography assessment of the efficacy of different rotary versus hand retreatment system

OpenAIRE

Neelam Mittal; Jyoti Jain

2014-01-01

Aims: The purpose of this study was to evaluate the efficacy of nickel-titanium rotary retreatment systems versus stainless steel hand retreatment system with or without solvent for gutta-percha removal during retreatment. Materials and Methods: Sixty extracted human mandibular molar teeth with single canal in a distal root was prepared with ProTaper rotary nickel-titanium files and obturated with gutta-percha and sealer. The teeth were randomly divided into six groups of 10 specimens in ...

Evaluation of apically extruded debris during root canal retreatment with two different rotary systems followed by a self-adjusting file.

Science.gov (United States)

Cakici, Fatih; Cakici, Elif B; Küçükekenci, Funda Fundaoglu

2016-02-01

To compare the amount of apically extruded debris during root canal retreatment using ProTaper retreatment system (Dentsply Maillefer, Ballaigues, Switzerland), ProTaper retreatment system with Self-Adjusting File (SAF) system (ReDent-Nova, Ra'anana, Israel), Mtwo retreatment system (VDW, Munich, Germany), Mtwo retreatment system with SAF instruments. In total, 72 extracted human mandibular incisor teeth were used. All root canals were prepared with ProTaper universal (Dentsply Maillefer) up to F2 file and filled with gutta percha and AH plus sealer using cold lateral condensation before being assembled randomly into 4 groups (n = 18 each). Root canal filling materials were removed using the ProTaper retreatment system, the ProTaper retreatment system followed by SAF system, Mtwo retreatment system and Mtwo retreatment system followed by SAF system. Debris extruded apically during the removal of canal filling material was collected into preweighed Eppendorf tubes. The tubes were then stored in an incubator at 70°C for 5 days. The weight of the dry extruded debris was established by subtracting the preretreatment and postretreatment weight of the Eppendorf tubes for each group. The data obtained were analyzed using Kruskal-Wallis test. All retreatment techniques caused the apical extrusion of debris. There was no significant difference between the groups statistically (p>0.05). The results of this study showed that SAF system after Mtwo retreatment system and ProTaper retreatment system for improving retreatment has no significant effect on the amount of debris extruded apically.

Safety of BTZ retreatment for patients with low-grade peripheral neuropathy during the initial treatment.

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Vidisheva, Aleksandra P; Wang, James; Spektor, Tanya M; Bitran, Jacob D; Lutzky, Jose; Tabbara, Imad A; Ye, Joseph Z; Ailawadhi, Sikander; Stampleman, Laura V; Steis, Ronald G; Moezi, Mehdi M; Swift, Regina A; Maluso, Tina M; Udd, Kyle A; Eshaghian, Shahrooz; Nassir, Youram; Berenson, James R

2017-10-01

Neuropathy is an important complication that may limit treatment options for patients with multiple myeloma. Previous studies have focused on treatment efficacy and have shown that retreatment with bortezomib (BTZ) is an effective treatment option. The goal of this study was to focus on the clinical manifestations of peripheral neuropathy (PN) and to retrospectively compare the incidence and severity of PN between the initial BTZ regimen and upon retreatment. Furthermore, this study evaluated how certain factors affect BIPN, which will help determine what conditions should be considered prior to retreatment. Charts were reviewed from 93 patients who were retreated with a BTZ-containing regimen after previously being treated with this drug. Among the patients who developed PN, most patients in the study had low-grade neuropathy during the initial BTZ treatment (n = 52, 68%). The results showed no evidence of cumulative toxicity, and there was no significant difference in the incidence and severity of PN upon retreatment. Factors such as the presence of baseline PN, number of prior treatments, dose of BTZ, and comorbidities did not increase the severity of PN upon retreatment. The lapse of time between the two regimens also did not affect the severity of PN. The results suggest that retreatment with BTZ may be a feasible option, without additional risks of PN, for MM patients even with peripheral neuropathy during their initial treatment with this drug.

Contrasting evidence of Holocene ice margin retreat, south-western Greenland

DEFF Research Database (Denmark)

Levy, L. B.; Larsen, N. K.; Davidson, T. A.

2017-01-01

Constraining the Greenland Ice Sheet's (GrIS) response to Holocene climate change provides calibrations for ice sheet models that hindcast past ice margin fluctuations. Ice sheet models predict enhanced ice retreat in south-western Greenland during the middle Holocene; however, few geological...... observations corroborating the extensive retreat are available. We present new data from lake sediment cores from the Isua region, south-western Greenland, which provide constraints on Holocene fluctuations of the GrIS margins. Our data indicate that the main GrIS margin was 30 km west of its present...

Measuring Surface Deformation in Glacier Retreated Areas Based on Ps-Insar - Geladandong Glacier as a Case Study

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Mohamadi, B.; Balz, T.

2018-04-01

Glaciers are retreating in many parts of the world as a result of global warming. Many researchers consider Qinghai-Tibetan Plateau as a reference for climate change by measuring glaciers retreat on the plateau. This retreat resulted in some topographic changes in retreated areas, and in some cases can lead to geohazards as landslides, and rock avalanches, which is known in glacier retreated areas as paraglacial slope failure (PSF). In this study, Geladandong biggest and main glacier mass was selected to estimate surface deformation on its glacier retreated areas and define potential future PSF based on PS-InSAR technique. 56 ascending and 49 descending images were used to fulfill this aim. Geladandong glacier retreated areas were defined based on the maximum extent of the glacier in the little ice age. Results revealed a general uplift in the glacier retreated areas with velocity less than 5mm/year. Obvious surface motion was revealed in seven parts surround glacier retreated areas with high relative velocity reached ±60mm/year in some parts. Four parts were considered as PSF potential motion, and two of them showed potential damage for the main road in the study area in case of rock avalanche into recent glacier lakes that could result in glacier lake outburst flooding heading directly to the road. Finally, further analysis and field investigations are needed to define the main reasons for different types of deformation and estimate future risks of these types of surface motion in the Qinghai-Tibetan Plateau.

Benthic Trophic Interactions in an Antarctic Shallow Water Ecosystem Affected by Recent Glacier Retreat.

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Francesca Pasotti

Full Text Available The western Antarctic Peninsula is experiencing strong environmental changes as a consequence of ongoing regional warming. Glaciers in the area are retreating rapidly and increased sediment-laden meltwater runoff threatens the benthic biodiversity at shallow depths. We identified three sites with a distinct glacier-retreat related history and different levels of glacial influence in the inner part of Potter Cove (King George Island, South Shetland Islands, a fjord-like embayment impacted since the 1950s by a tidewater glacier retreat. We compared the soft sediment meio- and macrofauna isotopic niche widths (δ13C and δ15N stable isotope analysis at the three sites to investigate possible glacier retreat-related influences on benthic trophic interactions. The isotopic niches were locally shaped by the different degrees of glacier retreat-related disturbance within the Cove. Wider isotopic niche widths were found at the site that has become ice-free most recently, and narrower niches at the older ice-free sites. At an intermediate state of glacier retreat-related disturbance (e.g. via ice-growler scouring species with different strategies could settle. The site at the earliest stage of post-retreat development was characterized by an assemblage with lower trophic redundancy. Generally, the isotopic niche widths increased with increasing size spectra of organisms within the community, excepting the youngest assemblage, where the pioneer colonizer meiofauna size class displayed the highest isotopic niche width. Meiofauna at all sites generally occupied positions in the isotopic space that suggested a detrital-pool food source and/or the presence of predatory taxa. In general ice scour and glacial impact appeared to play a two-fold role within the Cove: i either stimulating trophic diversity by allowing continuous re-colonization of meiofaunal species or, ii over time driving the benthic assemblages into a more compact trophic structure with

Benthic Trophic Interactions in an Antarctic Shallow Water Ecosystem Affected by Recent Glacier Retreat.

Science.gov (United States)

Pasotti, Francesca; Saravia, Leonardo Ariel; De Troch, Marleen; Tarantelli, Maria Soledad; Sahade, Ricardo; Vanreusel, Ann

2015-01-01

The western Antarctic Peninsula is experiencing strong environmental changes as a consequence of ongoing regional warming. Glaciers in the area are retreating rapidly and increased sediment-laden meltwater runoff threatens the benthic biodiversity at shallow depths. We identified three sites with a distinct glacier-retreat related history and different levels of glacial influence in the inner part of Potter Cove (King George Island, South Shetland Islands), a fjord-like embayment impacted since the 1950s by a tidewater glacier retreat. We compared the soft sediment meio- and macrofauna isotopic niche widths (δ13C and δ15N stable isotope analysis) at the three sites to investigate possible glacier retreat-related influences on benthic trophic interactions. The isotopic niches were locally shaped by the different degrees of glacier retreat-related disturbance within the Cove. Wider isotopic niche widths were found at the site that has become ice-free most recently, and narrower niches at the older ice-free sites. At an intermediate state of glacier retreat-related disturbance (e.g. via ice-growler scouring) species with different strategies could settle. The site at the earliest stage of post-retreat development was characterized by an assemblage with lower trophic redundancy. Generally, the isotopic niche widths increased with increasing size spectra of organisms within the community, excepting the youngest assemblage, where the pioneer colonizer meiofauna size class displayed the highest isotopic niche width. Meiofauna at all sites generally occupied positions in the isotopic space that suggested a detrital-pool food source and/or the presence of predatory taxa. In general ice scour and glacial impact appeared to play a two-fold role within the Cove: i) either stimulating trophic diversity by allowing continuous re-colonization of meiofaunal species or, ii) over time driving the benthic assemblages into a more compact trophic structure with increased

Can shrubs help to reconstruct historical glacier retreats?

International Nuclear Information System (INIS)

Buras, Allan; Hallinger, Martin; Wilmking, Martin

2012-01-01

In the 21st century, most of the world’s glaciers are expected to retreat due to further global warming. The range of this predicted retreat varies widely as a result of uncertainties in climate and glacier models. To calibrate and validate glacier models, past records of glacier mass balance are necessary, which often only span several decades. Long-term reconstructions of glacier mass balance could increase the precision of glacier models by providing the required calibration data. Here we show the possibility of applying shrub growth increments as an on-site proxy for glacier summer mass balance, exemplified by Salix shrubs in Finse, Norway. We further discuss the challenges which this method needs to meet and address the high potential of shrub growth increments for reconstructing glacier summer mass balance in remote areas. (letter)

Variability, trends, and predictability of seasonal sea ice retreat and advance in the Chukchi Sea

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Serreze, Mark C.; Crawford, Alex D.; Stroeve, Julienne C.; Barrett, Andrew P.; Woodgate, Rebecca A.

2016-10-01

As assessed over the period 1979-2014, the date that sea ice retreats to the shelf break (150 m contour) of the Chukchi Sea has a linear trend of -0.7 days per year. The date of seasonal ice advance back to the shelf break has a steeper trend of about +1.5 days per year, together yielding an increase in the open water period of 80 days. Based on detrended time series, we ask how interannual variability in advance and retreat dates relate to various forcing parameters including radiation fluxes, temperature and wind (from numerical reanalyses), and the oceanic heat inflow through the Bering Strait (from in situ moorings). Of all variables considered, the retreat date is most strongly correlated (r ˜ 0.8) with the April through June Bering Strait heat inflow. After testing a suite of statistical linear models using several potential predictors, the best model for predicting the date of retreat includes only the April through June Bering Strait heat inflow, which explains 68% of retreat date variance. The best model predicting the ice advance date includes the July through September inflow and the date of retreat, explaining 67% of advance date variance. We address these relationships by discussing heat balances within the Chukchi Sea, and the hypothesis of oceanic heat transport triggering ocean heat uptake and ice-albedo feedback. Developing an operational prediction scheme for seasonal retreat and advance would require timely acquisition of Bering Strait heat inflow data. Predictability will likely always be limited by the chaotic nature of atmospheric circulation patterns.

Re-treatment tuberculosis cases categorised as "other": are they properly managed?

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Hannock Tweya

Full Text Available BACKGROUND: Although the World Health Organization (WHO provides information on the number of TB patients categorised as "other", there is limited information on treatment regimens or treatment outcomes for "other". Such information is important, as inappropriate treatment can lead to patients remaining infectious and becoming a potential source of drug resistance. Therefore, using a cohort of TB patients from a large registration centre in Lilongwe, Malawi, our study determined the proportion of all TB re-treatment patients who were registered as "other", and described their characteristics and treatment outcomes. METHODS: This retrospective observational study used routine program data to determine the proportion of all TB re-treatment patients who were registered as "other" and describe their characteristics and treatment outcomes between January 2006 and December 2008. RESULTS: 1,384 (12% of 11,663 TB cases were registered as re-treatment cases. Of these, 898 (65% were categorised as "other": 707 (79% had sputum smear-negative pulmonary TB and 191 (21% had extra pulmonary TB. Compared to the smear-positive relapse, re-treatment after default (RAD and failure cases, smear-negative "other" cases were older than 34 years and less likely to have their HIV status ascertained. Among those with known HIV status, "other" TB cases were more likely to be HIV positive. Of TB patients categorised as "other", 462 (51% were managed on the first-line regimen with a treatment success rate of 63%. CONCLUSION: A large proportion of re-treatment patients were categorised as "other". Many of these patients were HIV-infected and over half were treated with a first-line regimen, contrary to national guidelines. Treatment success was low. More attention to recording, diagnosis and management of these patients is warranted as incorrect treatment regimen and poor outcomes could lead to the development of drug resistant forms of TB.

Damage to root dentin during retreatment procedures

NARCIS (Netherlands)

Shemesh, H.; Roeleveld, A.C.; Wesselink, P.R.; Wu, M.K.

2011-01-01

Introduction: The aim of this study was to explore the influence of retreatment procedures on the appearance of defects on the root canal walls. Methods: Two hundred mandibular premolars were divided into 4 groups. One group was left unprepared. The rest of the teeth were prepared with ProTaper

Retreating academics: creating spaces for the scholarship of ...

African Journals Online (AJOL)

, this paper explores particular spaces created to support academic engagement in the scholarship of teaching and learning: the space of writing retreats. The metaphor of 'tapestry' is used to capture the development of a complex conceptual ...

Reasons for Retreatment of Amalgam and Composite Restorations among the Patients Referring to Tabriz Faculty of Dentistry

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Siavash Savadi Oskoee

2007-06-01

Full Text Available

Background and aims. Retreatment of existing restorations not only requires a lot of money and time but also there is a danger of weakening tooth structure and irritating the pulp. Since awareness of the reasons for the retreatment of teeth will save the teeth from possible future failure, the aim of this study was to assess the reasons for retreatment of amalgam and composite restorations in patients referring to Tabriz Faculty of Dentistry.

Materials and methods. In this descriptive study, the subjects had previously received an amalgam or a composite restoration in the Operative Department by dental students and were judged to need retreatment in their second visit. A total of 300 defective teeth were selected by simple random sampling method. The data was collected through examination and questionnaires and analyzed using chi-square test.

Results. There was a statistically significant association between the type of the restorative material and the reason for retreatment (p=0.001.

Conclusion. Although the reasons for the retreatment of amalgam and composite restorations were different, recurrent caries was the main reason for the retreatment for both restorative materials.

Risk Factors for Retreatment Following Myopic LASIK with Femtosecond Laser and Custom Ablation for the Treatment of Myopia.

Science.gov (United States)

Kruh, Jonathan N; Garrett, Kenneth A; Huntington, Brian; Robinson, Steve; Melki, Samir A

2017-01-01

To identify risks factors for retreatment post-laser in situ keratomeliusis (LASIK). A retrospective chart review from December 2008 to September 2012 identified 1,402 patients (2,581 eyes) that underwent LASIK treatment for myopia with the Intralase™ FS, STAR S4 IR™ Excimer Laser, and WaveScan WaveFront™ technology. In this group, 83 patients were retreated. All charts were reviewed for preoperative age, gender, initial manifest refraction spherical equivalent (MRSE), total astigmatism, and iris registration. Increased incidence rates of retreatment post-LASIK were preoperative age >40 years (p -3.0 D (p = 0.02), and astigmatism >1D (p = 0.001). Iris registration capture did not significantly reduce the retreatment rate (p = 0.12). Risk factors for retreatment included preoperative age >40 years, initial MRSE > -3.0 D, and astigmatism >1D. There was no difference in retreatment rate for patients based on gender or iris registration capture.

Investigations into localized re-treatment of the retina with a 3-nanosecond laser.

Science.gov (United States)

Chidlow, Glyn; Plunkett, Malcolm; Casson, Robert J; Wood, John P M

2016-08-01

Subvisual retinal lasers necessarily cause clinically invisible lesions, hence, they could intentionally or inadvertently be targeted at precisely the same or an overlapping location during repeat laser treatment. Herein, we investigated the structural integrity and cellular responses of localized re-treatment using a nanosecond laser (2RT) currently in trials for early age-related macular degeneration. Rats were randomly assigned to one of five groups: sham, subvisual 2RT, subvisual 2RT re-treatment, visual effect 2RT, visual effect 2RT re-treatment. Re-treatment groups were lasered on days 0 and 21; single laser groups were only lasered on day 21. All rats were euthanized at day 28 and eyes were then dissected and processed for immunohistochemistry. For re-treatment, the laser was targeted at precisely the same locations on both delivery occasions. Analytical endpoints included monitoring of retinal vascular integrity overlying lesions, investigation into any potential choroidal neovascularization, assessment of the RPE, quantification of collateral injury to photoreceptors or other neuronal classes, and delineation of glial reactivity. Repeat laser administration to rats caused ostensibly identical retinal-RPE-choroid responses to those obtained in age-matched rats that received only a single application. Specifically, 7 days after treatment, RPE cells were re-populating lesion sites. No obvious consistent differences were evident between the single and repeat laser groups. Moreover, repeat laser caused no (measurable) additive injury to photoreceptors or other retinal neuronal classes from single laser treatment. In re-lasered animals, there was no increase in microglial activity overlying and adjacent to lesion sites relative to single lasered rats. Finally, there was no evidence of choroidal neovascularization after repeat laser treatment. The overall results provide a measure of confidence that re-treatment of patients with 2RT should not provide any

MEASURING SURFACE DEFORMATION IN GLACIER RETREATED AREAS BASED ON PS-INSAR – GELADANDONG GLACIER AS A CASE STUDY

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B. Mohamadi

2018-04-01

Full Text Available Glaciers are retreating in many parts of the world as a result of global warming. Many researchers consider Qinghai-Tibetan Plateau as a reference for climate change by measuring glaciers retreat on the plateau. This retreat resulted in some topographic changes in retreated areas, and in some cases can lead to geohazards as landslides, and rock avalanches, which is known in glacier retreated areas as paraglacial slope failure (PSF. In this study, Geladandong biggest and main glacier mass was selected to estimate surface deformation on its glacier retreated areas and define potential future PSF based on PS-InSAR technique. 56 ascending and 49 descending images were used to fulfill this aim. Geladandong glacier retreated areas were defined based on the maximum extent of the glacier in the little ice age. Results revealed a general uplift in the glacier retreated areas with velocity less than 5mm/year. Obvious surface motion was revealed in seven parts surround glacier retreated areas with high relative velocity reached ±60mm/year in some parts. Four parts were considered as PSF potential motion, and two of them showed potential damage for the main road in the study area in case of rock avalanche into recent glacier lakes that could result in glacier lake outburst flooding heading directly to the road. Finally, further analysis and field investigations are needed to define the main reasons for different types of deformation and estimate future risks of these types of surface motion in the Qinghai-Tibetan Plateau.

Orthograde endodontic retreatment of teeth with individual cast posts: Report of two cases

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Ramić Bojana

2012-01-01

Full Text Available Introduction. The failure of primary endodontic treatment is manifested by various clinical symptoms following endodontic therapy or, more frequently, by the development of chronic inflammatory process in the apex region without any subjective symptoms. In case of unfavorable outcome of the primary endodontic treatment, orthograde endodontic retreatment is the method of choice for a prolonged therapy. Outline of Cases. Two female patients, 47 and 44 years old, were presented at the Dental Clinic of Vojvodina for endodontic retreatment of teeth 22, 23 and 13, within the repeated prosthetic restoration. Intraradicular individual cast posts were removed using ultrasonic instruments. Remains of gutta-percha were removed by engine driven rotary re-treatment files, root canals were shaped and cleaned using the crown-down technique, and obturated with gutta-percha and epoxy-resin-based sealer using the lateral compaction technique. Conclusion. When there are metal posts or broken instruments in the root canal, the use of ultrasonic instruments is considered a safe method characterized by negligible tooth substance loss and minimal root damage causing fractures and perforations, and the entire procedure is effective and predictable. Non-surgical orthograde endodontic retreatment, when properly performed in accessible and penetrable root canals, achieves a high cure rate, good and lasting results and eliminates the need for radical procedures, such as apical surgery or tooth extraction. When nonsurgical endodontic retreatment is done, treated teeth must be restored by full coronal coverage as soon as possible, to prevent coronal leakage or fracture.

Means of Slope Retreat on the Na Pali Cliffs, Kauai, Hawaii

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Osborn, G.; Sheardown, A.; Blay, C.

2016-12-01

The spectacular, 500 to 600 m high, deeply grooved escarpment referred to as the Na Pali cliffs, on the northwest coast of Kauai, requires a substrate competent enough to hold up high steep cliffs yet erodible enough to allow generation of wide, deep grooves. These opposing tendencies are afforded by weathering of originally strong basalt that keeps pace with erosion. The fluted cliffs maintain a rather consistent slope angle, generally 50-60°, whether they are close to the shoreline or have retreated some distance from it, indicating that the slopes are retreating parallel to themselves. Previous literature promotes groundwater sapping or waterfall-plunge-pool erosion as the chief means of valley-head retreat, but there is no evidence that either concept provides a general explanation for retreat of the fluted cliffs. The eroding cliffs maintain steepness because as much rock is eroded at the base as at the top, and transported sediment is washed completely out of the gully system. The thin-bedded basalts exposed in the steep flutes are decomposed into irregularly alternating fine sediment of low to moderate cohesion and thoroughly fractured beds or lenses of solid but chemically weathered rock, and covered with a veneer of sparse grass. Erosion proceeds by episodic removal of thin grass-covered surficial sheets of the weathering products. Some of this process may be facilitated by shallow mass movement, but probably most of the work is done by overland and channelized flow during intense rainstorms. The Na Pali coast experiences one-hour rainfalls of 2-2.5 inches (1 year recurrence interval) and 5-6 inches (100 year recurrence interval); experiments by others on basaltic soils in Molokai suggest such rain is more than enough to generate erosion-inducing overland flow. Between the deep grooves and the shoreline are slopes with lesser drainage densities and lesser slope angles. The rocks here are not distinguished from the rocks above in previous literature, and

Climate Change and Glacier Retreat: Scientific Fact and Artistic Opportunity

Science.gov (United States)

Fagre, D. B.

2008-12-01

Mountain glaciers continue to retreat rapidly over most of the globe. In North America, at Glacier National Park, Montana, recent research results from Sperry Glacier (2005-2007) indicate negative mass balances are now 3-4 times greater than in the 1950s. A geospatial model of glacier retreat in the Blackfoot-Jackson basin suggested all glaciers would be gone by 2030 but has proved too conservative. Accelerated glacier shrinkage since the model was developed has mirrored an increase in actual annual temperature that is almost twice the rate used in the model. The glaciers in Glacier National Park are likely to be gone well before 2030. A variety of media, curricula, and educational strategies have been employed to communicate the disappearance of the glaciers as a consequence of global warming. These have included everything from print media and television coverage to podcasts and wayside exhibits along roads in the park. However, a new thrust is to partner with artists to communicate climate change issues to new audiences and through different channels. A scientist-artist retreat was convened to explore the tension between keeping artistic products grounded in factually-based reality while providing for freedom to express artistic creativity. Individual artists and scientists have worked to create aesthetic and emotional images, using painting, poetry, music and photography, to convey core messages from research on mountain ecosystems. Finally, a traveling art exhibit was developed to highlight the photography that systematically documents glacier change through time. The aim was to select photographs that provide the most compelling visual experience for an art-oriented viewer and also accurately reflect the research on glacier retreat. The exhibit opens on January 11, 2009

Psychological effects of a one-month meditation retreat on experienced meditators: the role of nonattachment

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Jesus Montero-Marin

2016-12-01

Full Text Available Background. There are few studies devoted to assessing the impact of meditation-intensive retreats on the well-being, positive psychology and personality of experienced meditators. We aimed to assess whether a 1-month Vipassana retreat: a would increase mindfulness and well-being; b would increase prosocial personality traits; and c whether psychological changes would be mediated and/or moderated by non-attachment.Method. A controlled, non-randomized, pre-post-intervention trial was used. The intervention group was a convenience sample (n=19 of experienced meditators who participated in a 1-month Vipassana meditation retreat. The control group (n=19 comprised matched experienced meditators who did not take part in the retreat. During the retreat, the mean duration of daily practice was 8-9 hours, the diet was vegetarian and silence was compulsory. The Experiences Questionnaire (EQ, Non-Attachment Scale (NAS, Positive and Negative Affect Schedule (PANAS, Satisfaction With Life Scale (SWLS, Temperament Character Inventory Revised (TCI-R-67, Five Facets Mindfulness Questionnaire (FFMQ, Self-Other Four Immeasurables (SOFI and the MINDSENS Composite Index were administered. ANCOVAs and linear regression models were used to assess pre-post changes and mediation/moderation effects.Results. Compared to controls, retreatants showed increases in non-attachment, observing, MINDSENS, positive-affect, balance-affect and cooperativeness; and decreases in describing, negative-others, reward-dependence and self-directedness. Non-attachment had a mediating role in decentring, acting aware, non-reactivity, negative-affect, balance-affect and self-directedness; and a moderating role in describing and positive others, with both mediating and moderating effects on satisfaction with life.Conclusions. A 1-month Vipassana meditation retreat seems to yield improvements in mindfulness, well-being and personality, even in experienced meditators. Non-attachment might

Sub-ice-shelf sediments record history of twentieth-century retreat of Pine Island Glacier.

Science.gov (United States)

Smith, J A; Andersen, T J; Shortt, M; Gaffney, A M; Truffer, M; Stanton, T P; Bindschadler, R; Dutrieux, P; Jenkins, A; Hillenbrand, C-D; Ehrmann, W; Corr, H F J; Farley, N; Crowhurst, S; Vaughan, D G

2017-01-05

The West Antarctic Ice Sheet is one of the largest potential sources of rising sea levels. Over the past 40 years, glaciers flowing into the Amundsen Sea sector of the ice sheet have thinned at an accelerating rate, and several numerical models suggest that unstable and irreversible retreat of the grounding line-which marks the boundary between grounded ice and floating ice shelf-is underway. Understanding this recent retreat requires a detailed knowledge of grounding-line history, but the locations of the grounding line before the advent of satellite monitoring in the 1990s are poorly dated. In particular, a history of grounding-line retreat is required to understand the relative roles of contemporaneous ocean-forced change and of ongoing glacier response to an earlier perturbation in driving ice-sheet loss. Here we show that the present thinning and retreat of Pine Island Glacier in West Antarctica is part of a climatically forced trend that was triggered in the 1940s. Our conclusions arise from analysis of sediment cores recovered beneath the floating Pine Island Glacier ice shelf, and constrain the date at which the grounding line retreated from a prominent seafloor ridge. We find that incursion of marine water beyond the crest of this ridge, forming an ocean cavity beneath the ice shelf, occurred in 1945 (±12 years); final ungrounding of the ice shelf from the ridge occurred in 1970 (±4 years). The initial opening of this ocean cavity followed a period of strong warming of West Antarctica, associated with El Niño activity. Thus our results suggest that, even when climate forcing weakened, ice-sheet retreat continued.

Endodontic retreatment decisions: no consensus.

Science.gov (United States)

Aryanpour, S; Van Nieuwenhuysen, J P; D'Hoore, W

2000-05-01

The objectives of the present study were to: (i) evaluate the consensus, if any, amongst dental schools, students and their instructors managing the same clinical cases, all of which involved endodontically treated teeth; and (ii) determine the predominant proposed treatment option. Final year students, endodontic staff members and instructors of 10 European dental schools were surveyed as decision makers. Fourteen different radiographic cases of root canal treated teeth accompanied by a short clinical history were presented to them in a uniform format. For each case the decision makers were requested to: (i) choose only one out of nine treatment alternatives proposed, from 'no treatment' to 'extraction' via 'retreatment' and 'surgery' (ii) assess on two 5-point scales: the difficulty of making a decision, and the technical complexity of the retreatment procedure. The results indicate wide inter- and also intra-school disagreements in the clinical management of root canal treated teeth. Analysis of variance showed that the main source of variation was the 'school effect', explaining 1.8% (NS) to 18.6% (P < 0.0001) of the treatment variations. No other factor explained as much variance. Decision difficulty was moderately correlated to technical complexity (Pearsons' r ranging from 0.19 to 0.35, P < 0.0001). No clear consensus occurred amongst and within dental schools concerning the clinical management of the 14 cases. The lack of consensus amongst schools seems to be due mainly to chance or uncertainty, but can be partly explained by the 'school effect'.

Power grid control in retreat

International Nuclear Information System (INIS)

Morch, Stein

2000-01-01

Bilateral grid control that obstructs free trade of electricity is in retreat. Negotiations on opening the Skagerrak cables are in progress. The EU, national authorities, network companies with system responsibility, market actors, electricity exchanges all push for quick opening of the grid. At present, free trade of electricity is hindered not so much by physical bottlenecks in the grid as by market actors possessing control and bilateral agreements. The article discusses current bilateral agreements and how they might affect the possibility of a free trade of electricity in Europe

Retreat of Stephenson Glacier, Heard Island, from Remote Sensing and Field Observations

Science.gov (United States)

Mitchell, W.; Schmieder, R.

2017-12-01

Heard Island (Australian sub-Antarctic territory, 53 S, 73.5 E) is a volcanic island mantled in glaciers, and a UNESCO World Heritage Site both for its geology and ecology. Lying to the south of the Antarctic Convergence, the changes in response to climate seen on Heard Island are likely to be a bellwether for areas further south. Beginning in 1999, American satellites (Landsat 7, EO-1, and Landsat 8) have produced images of the island on a roughly weekly basis. Although the island is often shrouded in clouds, clear images of at least portions of the island are plentiful enough to create a nearly-annual record of the toe of Stephenson Glacier. During this period, Stephenson Glacier retreated by nearly 5 km, and lost 50% of its area. As a result of this retreat, a portion of the glacier now could be classified as a separate glacier. Additionally, in 2016, terrestrial photographs of Stephenson Glacier were taken during a three-week expedition to Heard Island, which accessed the Stephenson Glacier area by boat via the proglacial Stephenson Lagoon. During that work, sonar indicated some depths in the lagoon exceeding 100 m. Much of the loss in glacier length and area occurred during the mid- and late-2000s, with retreat rates slowing toward 2017. At this time, the glacier has retreated so that the main toe is not far from the base of a tall ice falls, while another toe—perhaps now a separate glacier—is land-based. This type of retreat pattern, fast over water and slower on land, is typical of other tidewater glaciers. Further monitoring of Stephenson Glacier and other glaciers on Heard Island will continue using Landsat 8.

Efficacy of protaper next and protaper universal retreatment systems in removing gutta-percha in curved root canals during root canal retreatment.

Science.gov (United States)

Ozyurek, Taha; Ozsezer-Demiryurek, Ebru

2017-01-01

The aim of this study was to compare the cleanliness of root canal walls after retreatment using ProTaper Next (PTN), ProTaper Universal Retreatment (PTR) nickel-titanium (NiTi) systems and Hedström hand files in curved mesial canals of mandibular molar teeth and the time required for gutta-percha and sealer removal. Ninety mandibular molar teeth with curved mesial roots were instrumented up to #35.04 with Mtwo NiTi rotary instruments and obturated using the continuous wave of condensation technique. Removal of gutta-percha and sealer was performed using one of the following: PTN and PTR NiTi systems and Hedström hand files. Samples were placed on the VistaScan phosphor plates in the mesio-distal direction and the radiographs were taken. The digital radiographs were analyzed using AutoCAD software. Also, the total time required for gutta-percha removal was calculated by a chronometer. The total retreatment time was significantly shorter in the PTN and PTR groups compared with the manual group (p<0.05). There was a significant difference between the groups according to the total residual gutta-percha and sealer (p<0.05). The PTN and PTR groups left significantly less gutta-percha and sealer remnant than the manual group (p<0.001). Within the limitations of this study, the PTN and PTR groups showed less residual gutta-percha and sealer than the manual group. The NiTi rotary systems were significantly faster than the manual group in the time required for gutta-percha and sealer removal.

Retreatment and outcomes of recurrent intracranial vertebral artery dissecting aneurysms after stent assisted coiling: a single center experience.

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Ying Song

Full Text Available The retreatment of recurrent intracranial vertebral artery dissecting aneurysms (VADAs after stent assisted coiling (SAC has not yet been studied. The purpose of this study was to evaluate the strategies and outcomes for retreatment of recurrent VADAs after SAC.Between September 2009 and November 2013, six consecutive patients presenting with recurrent intracranial VADAs after SAC were enrolled in this study. They were all male with age ranging from 29 to 54 years (mean age, 46.2 years. The procedures of treatments and angiographic and clinical follow-up were reviewed retrospectively. Retreatment modalities were selected individually according to the characteristics of recurrence. The outcomes of retreatment were evaluated by angiographic and clinical follow-up.Six patients with recurrent intracranial VADAs after SAC were retreated, with second SAC in three patients, coil embolization, double overlapping stents placement and endovascular occlusion with aneurysm trapping in one patient, respectively. Immediate angiographic outcomes of retreatment were: complete occlusion in three patients, nearly complete occlusion in two patients, and contrast medium retention in dissecting aneurysm in one patient. All cases were technically successful. No complications related to endovascular procedures occurred. Angiographic follow-up was available in all five patients treated with second SAC or double overlapping stents, which was complete occlusion in four patients, obliteration of parent artery in one patient, showing no recurrence at 4-11 months (mean: 8.6 months. Clinical follow-up was performed in all six patients at 11-51 months after initial endovascular treatment and at 9-43 months after retreatment. The mRS of last clinical follow-up was excellent in five patients and mild disability in only one patient.Endovascular retreatment is feasible and effective for recurrent intracranial VADAs after SAC. Individualized strategies of retreatment should be

To evaluate and compare the efficacy, cleaning ability of hand and two rotary systems in root canal retreatment.

Science.gov (United States)

Shivanand, Sunita; Patil, Chetan R; Thangala, Venugopal; Kumar, Pabbati Ravi; Sachdeva, Jyoti; Krishna, Akash

2013-05-01

To evaluate and compare the efficacy, cleaning ability of hand and two rotary systems in root canal retreatment. Sixty extracted premolars were retreated with following systems: Group -ProTaper Universal retreatment files, Group 2-ProFile system, Group 3-H-file. Specimens were split longitudinally and amount of remaining gutta-percha on the canal walls was assessed using direct visual scoring with the aid of stereomicroscope. Results were statistically analyzed using ANOVA test. Completely clean root canal walls were not achieved with any of the techniques investigated. However, all three systems proved to be effective for gutta-percha removal. Significant difference was found between ProTaper universal retreatment file and H-file, and also between ProFile and H-file. Under the conditions of the present study, ProTaper Universal retreatment files left significantly less guttapercha and sealer than ProFile and H-file. Rotary systems in combination with gutta-percha solvents can perform superiorly as compared to the time tested traditional hand instrumentation in root canal retreatment.

Efficacy of Different Methods for Removing Root Canal Filling Material in Retreatment - An In-vitro Study.

Science.gov (United States)

Kasam, Swetha; Mariswamy, Annapoorna Ballagere

2016-06-01

Although success of endodontic therapy has significantly improved in the last few decades due to the introduction of novel materials and techniques, failures of endodontic therapy requiring re-treatment still comprise a significant percentage of patients requiring root canal treatment. To evaluate and compare the effective removal of gutta percha and sealer, amount of apical debris extrusion and time required for gutta percha removal using various endodontic files. Total 48 extracted mandibular premolars were mounted on acrylic blocks and endodontic procedure was carried out using size 40 K file and obturated using guttapercha and zinc oxide eugenol sealer. After one month storage, samples were decoronated, mounted on screw capped vials and subjected to removal of obturated material by four instruments: H files, safe sided H files, protaper universal retreatment rotary system and ultrasonic retreatment tip, grouped as 1, 2, 3, and 4 respectively. Only 2mm of obturated material from the coronal part was removed using no. 3 Gates Glidden drill, guttapercha was softened with a drop of xylene for 2 mins for each canal and retreatment was performed. The retreatment procedure was said to be complete when no visible debris were observed on the instrument flutes. The samples split into two halves and examined under stereomicroscope, photographed, assessed using AUTOCAD software and percentage of remaining filling material in coronal, middle, apical thirds of the canal was calculated in mm(2). Retreatment time was recorded in seconds and apically extruded debris was assessed by microbalance in grams for each tooth. The data was analyzed by using descriptive statistics, ANOVA and Scheffe's post hoc test through SPSS for windows (v 16.0). The ultrasonic retreatment tip had less percentage of residual guttapercha/sealer, shorter mean operating time and little apical extrusion with a significant difference (p<0.05) between the other groups. All techniques retained guttapercha

Efficacy of reciprocating and rotary NiTi instruments for retreatment of curved root canals assessed by micro-CT.

Science.gov (United States)

Rödig, T; Reicherts, P; Konietschke, F; Dullin, C; Hahn, W; Hülsmann, M

2014-10-01

To compare the efficacy of reciprocating and rotary NiTi-instruments in removing filling material from curved root canals using micro-computed tomography. Sixty curved root canals were prepared and filled with gutta-percha and sealer. After determination of root canal curvatures and radii in two directions as well as volumes of filling material, the teeth were assigned to three comparable groups (n = 20). Retreatment was performed using Reciproc, ProTaper Universal Retreatment or Hedström files. Percentages of residual filling material and dentine removal were assessed using micro-CT imaging. Working time and procedural errors were recorded. Statistical analysis was performed by variance procedures. No significant differences amongst the three retreatment techniques concerning residual filling material were detected (P > 0.05). Hedström files removed significantly more dentine than ProTaper Universal Retreatment (P  0.05). Reciproc and ProTaper Universal Retreatment were significantly faster than Hedström files (P = 0.0001). No procedural errors such as instrument fracture, blockage, ledging or perforation were detected for Hedström files. Three perforations were recorded for ProTaper Universal Retreatment, and in both NiTi groups, one instrument fracture occured. Remnants of filling material were observed in all samples with no significant differences between the three techniques. Hedström files removed significantly more dentine than ProTaper Universal Retreatment, but no significant differences between both NiTi systems were detected. Procedural errors were observed with ProTaper Universal Retreatment and Reciproc. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Do Wellness Tourists Get Well? An Observational Study of Multiple Dimensions of Health and Well-Being After a Week-Long Retreat.

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Cohen, Marc M; Elliott, Fiona; Oates, Liza; Schembri, Adrian; Mantri, Nitin

2017-02-01

Wellness retreats use many complementary and alternative therapies within a holistic residential setting, yet few studies have evaluated the effect of retreat experiences on multiple dimensions of health and well-being, and no published studies have reported health outcomes in wellness tourists. To assess the effect of a week-long wellness-retreat experience in wellness tourists. A longitudinal observational study with outcomes assessed upon arrival and departure and 6 weeks after the retreat. A rural health retreat in Queensland, Australia. A holistic, 1-week, residential, retreat experience that included many educational, therapeutic, and leisure activities and an organic, mostly plant-based diet. Multiple outcome measures were performed upon arrival and departure and 6 weeks after the retreat. These included anthropometric measures, urinary pesticide metabolites, a food and health symptom questionnaire, the Five Factor Wellness Inventory, the General Self Efficacy questionnaire, the Pittsburgh Insomnia Rating Scale, the Depression Anxiety Stress Scale, the Profile of Mood States, and the Cogstate cognitive function test battery. Statistically significant improvements (p effects and assess the value and relevance of retreat experiences to clinicians and health insurers.

Psychological Effects of a 1-Month Meditation Retreat on Experienced Meditators: The Role of Non-attachment.

Science.gov (United States)

Montero-Marin, Jesus; Puebla-Guedea, Marta; Herrera-Mercadal, Paola; Cebolla, Ausias; Soler, Joaquim; Demarzo, Marcelo; Vazquez, Carmelo; Rodríguez-Bornaetxea, Fernando; García-Campayo, Javier

2016-01-01

Background: There are few studies devoted to assessing the impact of meditation-intensive retreats on the well-being, positive psychology, and personality of experienced meditators. We aimed to assess whether a 1-month Vipassana retreat: (a) would increase mindfulness and well-being; (b) would increase prosocial personality traits; and (c) whether psychological changes would be mediated and/or moderated by non-attachment. Method: A controlled, non-randomized, pre-post-intervention trial was used. The intervention group was a convenience sample ( n = 19) of experienced meditators who participated in a 1-month Vipassana meditation retreat. The control group ( n = 19) comprised matched experienced meditators who did not take part in the retreat. During the retreat, the mean duration of daily practice was 8-9 h, the diet was vegetarian and silence was compulsory. The Experiences Questionnaire (EQ), Non-attachment Scale (NAS), Positive and Negative Affect Schedule (PANAS), Satisfaction With Life Scale (SWLS), Temperament Character Inventory Revised (TCI-R-67), Five Facets Mindfulness Questionnaire (FFMQ), Self-Other Four Immeasurables (SOFI) and the MINDSENS Composite Index were administered. ANCOVAs and linear regression models were used to assess pre-post changes and mediation/moderation effects. Results: Compared to controls, retreatants showed increases in non-attachment, observing, MINDSENS, positive-affect, balance-affect, and cooperativeness; and decreases in describing, negative-others, reward-dependence and self-directedness. Non-attachment had a mediating role in decentring, acting aware, non-reactivity, negative-affect, balance-affect and self-directedness; and a moderating role in describing and positive others, with both mediating and moderating effects on satisfaction with life. Conclusions: A 1-month Vipassana meditation retreat seems to yield improvements in mindfulness, well-being, and personality, even in experienced meditators. Non-attachment might

EFFICACY OF PROTAPER NEXT AND PROTAPER UNIVERSAL RETREATMENT SYSTEMS IN REMOVING GUTTA-PERCHA IN CURVED ROOT CANALS DURING ROOT CANAL RETREATMENT

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Taha ÖZYÜREK

2017-04-01

Full Text Available Purpose: The aim of this study was to compare the cleanliness of root canal walls after retreatment using ProTaper Next (PTN, ProTaper Universal Retreatment (PTR nickel-titanium (NiTi systems and Hedström hand files in curved mesial canals of mandibular molar teeth and the time required for gutta-percha and sealer removal. Materials and Methods: Ninety mandibular molar teeth with curved mesial roots were instrumented up to #35.04 with Mtwo NiTi rotary instruments and obturated using the continuous wave of condensation technique. Removal of gutta-percha and sealer was performed using one of the following: PTN and PTR NiTi systems and Hedström hand files. Samples were placed on the VistaScan phosphor plates in the mesio-distal direction and the radiographs were taken. The digital radiographs were analyzed using AutoCAD software. Also, the total time required for gutta-percha removal was calculated by a chronometer. Results: The total retreatment time was significantly shorter in the PTN and PTR groups compared with the manual group (p<0.05. There was a significant difference between the groups according to the total residual gutta-percha and sealer (p<0.05. The PTN and PTR groups left significantly less gutta-percha and sealer remnant than the manual group (p<0.001. Conclusion: Within the limitations of this study, the PTN and PTR groups showed less residual gutta-percha and sealer than the manual group. The NiTi rotary systems were significantly faster than the manual group in the time required for gutta-percha and sealer removal.

Efficacy and safety of bortezomib-based retreatment at the first relapse in multiple myeloma patients: A retrospective study.

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Oriol, Albert; Giraldo, Pilar; Kotsianidis, Ioannis; Couturier, Catherine; Olie, Robert; Angermund, Ralf; Corso, Alessandro

2015-08-01

Multiple myeloma remains incurable and retreatment with available therapies is of substantial interest. This retrospective observational study included data from 35 patients treated initially and at the first relapse with bortezomib-containing regimens. Bortezomib retreatment provided a similar depth and time to response as first-line therapy; however, as could be expected, the duration of response was shorter with retreatment. The tolerability profile was similar with bortezomib as the first- and second-line therapy, with no evidence of cumulative toxicity. These findings support bortezomib retreatment after a treatment-free interval of ≥6 months in patients who achieved at least a partial response to the first-line bortezomib-based therapy.

Habitat selection in a rocky landscape: experimentally decoupling the influence of retreat site attributes from that of landscape features.

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Benjamin M Croak

Full Text Available Organisms selecting retreat sites may evaluate not only the quality of the specific shelter, but also the proximity of that site to resources in the surrounding area. Distinguishing between habitat selection at these two spatial scales is complicated by co-variation among microhabitat factors (i.e., the attributes of individual retreat sites often correlate with their proximity to landscape features. Disentangling this co-variation may facilitate the restoration or conservation of threatened systems. To experimentally examine the role of landscape attributes in determining retreat-site quality for saxicolous ectotherms, we deployed 198 identical artificial rocks in open (sun-exposed sites on sandstone outcrops in southeastern Australia, and recorded faunal usage of those retreat sites over the next 29 months. Several landscape-scale attributes were associated with occupancy of experimental rocks, but different features were important for different species. For example, endangered broad-headed snakes (Hoplocephalus bungaroides preferred retreat sites close to cliff edges, flat rock spiders (Hemicloea major preferred small outcrops, and velvet geckos (Oedura lesueurii preferred rocks close to the cliff edge with higher-than-average sun exposure. Standardized retreat sites can provide robust experimental data on the effects of landscape-scale attributes on retreat site selection, revealing interspecific divergences among sympatric taxa that use similar habitats.

A comparative evaluation of efficacy of protaper universal rotary retreatment system for gutta-percha removal with or without a solvent.

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Kumar, M Sita Ram; Sajjan, Girija S; Satish, Kalyan; Varma, K Madhu

2012-09-01

The aim was to evaluate and compare the efficacy of ProTaper Universal rotary retreatment system with or without solvent and stainless steel hand files for endodontic filling removal from root canals and also to compare retreatment time for each system. Thirty extracted mandibular premolars with single straight canals were endodontically treated. Teeth were divided into three major groups, having 10 specimens each. Removal of obturating material in group 1 by stainless steel hand files with RC Solve, group 2 by ProTaper Universal retreatment instruments and group 3 by ProTaper Universal retreatment instruments along with RC solve was done. Retreatment was considered complete for all groups when no filling material was observed on the instruments. The retreatment time was recorded for each tooth. All specimens were grooved longitudinally in a buccolingual direction. The split halves were examined under a stereomicroscope and images were captured and analyzed. The remaining filling debris area ratios were considered for statistical analysis. With ANOVA test, statistical analysis showed that there was statistically no significant difference regarding the amount of filling remnants between the groups (P ProTaper Universal retreatment system files alone proved to be faster than the other experimental groups.

Reconceptualizing Leadership in Migrant Communities: Latina/o Parent Leadership Retreats as Sites of Community Cultural Wealth

Science.gov (United States)

Nava, Pedro E.; Lara, Argelia

2016-01-01

This article examines how the Education Leadership Foundation (a leadership development community based organization) in partnership with the Migrant Education Program use parent retreats for building leadership, and skill development of migrant farm-working families. Utilizing cooperative and community responsive practices, these retreats build…

Effect of Topography on Subglacial Discharge and Submarine Melting During Tidewater Glacier Retreat

Science.gov (United States)

Amundson, J. M.; Carroll, D.

2018-01-01

To first order, subglacial discharge depends on climate, which determines precipitation fluxes and glacier mass balance, and the rate of glacier volume change. For tidewater glaciers, large and rapid changes in glacier volume can occur independent of climate change due to strong glacier dynamic feedbacks. Using an idealized tidewater glacier model, we show that these feedbacks produce secular variations in subglacial discharge that are influenced by subglacial topography. Retreat along retrograde bed slopes (into deep water) results in rapid surface lowering and coincident increases in subglacial discharge. Consequently, submarine melting of glacier termini, which depends on subglacial discharge and ocean thermal forcing, also increases during retreat into deep water. Both subglacial discharge and submarine melting subsequently decrease as glacier termini retreat out of deep water and approach new steady state equilibria. In our simulations, subglacial discharge reached peaks that were 6-17% higher than preretreat values, with the highest values occurring during retreat from narrow sills, and submarine melting increased by 14% for unstratified fjords and 51% for highly stratified fjords. Our results therefore indicate that submarine melting acts in concert with iceberg calving to cause tidewater glacier termini to be unstable on retrograde beds. The full impact of submarine melting on tidewater glacier stability remains uncertain, however, due to poor understanding of the coupling between submarine melting and iceberg calving.

Overall response rates to radiation therapy for patients with painful uncomplicated bone metastases undergoing initial treatment and retreatment

International Nuclear Information System (INIS)

Bedard, Gillian; Hoskin, Peter; Chow, Edward

2014-01-01

Introduction: Radiation therapy has been shown to successfully palliate bone metastases. A number of systematic reviews and large clinical trials have reported response rates for initial treatment and retreatment. Objective: To determine overall response rates of patients with painful uncomplicated bone metastases undergoing initial treatment and retreatment. Methods: Intent-to-treat and evaluable patient statistics from a systematic review of palliative radiotherapy trials for initial treatment of bone metastases and a randomized clinical trial of retreatment were pooled and analyzed to determine the overall response rates for patients receiving initial treatment and retreatment. Results: In the intent-to-treat calculation, 71–73% of patients had an overall response to radiation treatment and in the evaluable patient population; 85–87% of patients did so. Response rates varied slightly whether patients underwent single or multiple fractions in initial treatment or retreatment. Conclusions: Single and multiple fraction radiation treatment yielded very similar overall response rates. Patients treated with a single fraction for both initial and repeat radiation experience almost identical overall response to those patients treated with multiple fraction treatment. It is therefore recommended that patients with uncomplicated painful bone metastases be treated with a single 8 Gy fraction of radiation at both the initial treatment and retreatment

Salt Marshes as Monitors of Late Holocene Outlet Glacier Retreat

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Wake, L. M.; Woodroffe, S.; Long, A. J.; Milne, G. A.

2014-12-01

New proxy sea-level records extracted from salt marshes in the vicinity of Jakobshavn Isbrae (Pakitsoq; 69.51°N, 50.74°W) and at previous sites in central western Greenland (Sisimiut; 66.47°N, 53.61°W and Aasiaat; 68.69°N, 52.88°W) are analyzed with respect to their ability to act as proximal tide gauges detecting mass balance changes in nearby outlet glaciers associated with the transition from the Little Ice Age ("LIA", 1400-1850AD) to the Industrial Period (>1850AD). Data at Pakitsoq demonstrate that sea-level rose at a rate of 3.5 ±1.7 mm/yr prior to 1850AD and slowed to 0.3 ±0.6mm/yr thereafter, producing a slowdown in sea level of 3.2 ± 1.8 mm/yr. A similar slowdown, occurring at 1600AD, is observed at Aasiaat and Sisimiut. We interpret these observed changes using a glacial isostatic adjustment model of sea-level change truncated at degree and order 4096, with an aim to determine if the sea-level data can be used to place constraints on changes in Jakobshavn Isbrae and/or Kangiata Nunaata Sermia (Nuuk fjord) during this period. Modelled sea level at Pakitsoq is insensitive to the location of thickening (thinning) associated with grounding line advance (retreat) and the rate of advance and retreat but is sensitive to the change point in time between periods of growth associated with LIA expansion (sea level rise) and the onset of 19th century recession (sea level fall) of Jakobshavn Isbrae. We conclude that the change in sea-level rate observed at Pakitsoq circa 1850AD marks the onset of post LIA retreat of this outlet glacier. Conversely, the modelled sea-level response to the retreat of Kangiata Nunaata Sermia from its LIA maximum at ca. 1761AD is below the detection threshold of the salt marsh record at Sisimiut.

A comparative evaluation of efficacy of protaper universal rotary retreatment system for gutta-percha removal with or without a solvent

Directory of Open Access Journals (Sweden)

M Sita Ram Kumar

2012-01-01

Full Text Available Aim: The aim was to evaluate and compare the efficacy of ProTaper Universal rotary retreatment system with or without solvent and stainless steel hand files for endodontic filling removal from root canals and also to compare retreatment time for each system. Materials and Methods: Thirty extracted mandibular premolars with single straight canals were endodontically treated. Teeth were divided into three major groups, having 10 specimens each. Removal of obturating material in group 1 by stainless steel hand files with RC Solve, group 2 by ProTaper Universal retreatment instruments and group 3 by ProTaper Universal retreatment instruments along with RC solve was done. Retreatment was considered complete for all groups when no filling material was observed on the instruments. The retreatment time was recorded for each tooth. All specimens were grooved longitudinally in a buccolingual direction. The split halves were examined under a stereomicroscope and images were captured and analyzed. The remaining filling debris area ratios were considered for statistical analysis. Results: With ANOVA test, statistical analysis showed that there was statistically no significant difference regarding the amount of filling remnants between the groups (P < 0.05. Differences between the means of groups are statistically significant regarding the retreatment time. Conclusion: Irrespective of the technique used, all the specimens had some remnants on the root canal wall. ProTaper Universal retreatment system files alone proved to be faster than the other experimental groups.

Differences in the clinical-epidemiological profile between new cases of tuberculosis and retreatment cases after default

Directory of Open Access Journals (Sweden)

Aylana de Souza Belchior

Full Text Available Abstract OBJECTIVE To identify the socioeconomic and clinical-epidemiological factors related to tuberculosis in new cases and retreatment cases. METHOD Comparative study with 126 patients, of which 42 were retreatment cases after default attended in a reference center, and 84 were new cases completing the first treatment and treated in Basic Health Units. The collection of primary data was through interview, and of secondary data by records of the Notifiable Diseases Information System. Comparative analysis between the two groups. RESULTS The new cases differ from retreatment cases regarding educational level. The clinical-epidemiological profile shows a significant difference in relation to performance of the tuberculin skin test, and the HIV test result (positive in favor of new cases. In relation to performance of sputum culture and the result (positive of the first sputum smear of the first and second samples, in favor of retreatment cases. CONCLUSION The two groups are significantly different in clinical and epidemiological characteristics that show the access to exams.

A model ensemble for projecting multi‐decadal coastal cliff retreat during the 21st century

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Limber, Patrick; Barnard, Patrick; Vitousek, Sean; Erikson, Li

2018-01-01

Sea cliff retreat rates are expected to accelerate with rising sea levels during the 21st century. Here we develop an approach for a multi‐model ensemble that efficiently projects time‐averaged sea cliff retreat over multi‐decadal time scales and large (>50 km) spatial scales. The ensemble consists of five simple 1‐D models adapted from the literature that relate sea cliff retreat to wave impacts, sea level rise (SLR), historical cliff behavior, and cross‐shore profile geometry. Ensemble predictions are based on Monte Carlo simulations of each individual model, which account for the uncertainty of model parameters. The consensus of the individual models also weights uncertainty, such that uncertainty is greater when predictions from different models do not agree. A calibrated, but unvalidated, ensemble was applied to the 475 km‐long coastline of Southern California (USA), with 4 SLR scenarios of 0.5, 0.93, 1.5, and 2 m by 2100. Results suggest that future retreat rates could increase relative to mean historical rates by more than two‐fold for the higher SLR scenarios, causing an average total land loss of 19 – 41 m by 2100. However, model uncertainty ranges from +/‐ 5 – 15 m, reflecting the inherent difficulties of projecting cliff retreat over multiple decades. To enhance ensemble performance, future work could include weighting each model by its skill in matching observations in different morphological settings

Comparison of the amount of apically extruded debris produced by four retreatment techniques: an ex vivo study

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Cristiane Ferreira Alfenas

2017-12-01

Full Text Available Objective: the aim of this study was to compare the amount of apically extruded debris during the removal of root canal filling material using nickel-titanium rotary retreatment instruments and Hedström files. Material and Methods: sixty mandibular incisors with a single canal were instrumented and obturated by cold lateral compaction. For retreatment, specimens were randomly divided into four groups (n = 15: Hedström files with or without solvent; D-RaCe system and Mtwo retreatment system. Debris extruded apically during the removal of canal filling material was collected into preweighed Eppendorf tubes. The tubes were then stored in an incubator at 70°C for 5 days. The weight of the dry extruded debris was established by subtracting the preretreatment and postretreatment weight of the Eppendorf tubes for each group. The mean weights of extruded material were analyzed by one-way ANOVA. Results: the results showed that all retreatment techniques caused apical extrusion of debris, but no statistically significant difference was observed between groups (p>0.05. Conclusion: under the conditions of this study, all retreatment techniques caused apical debris extrusion.

Incidence of flare-ups and evaluation of quality after retreatment of resorcinol-formaldehyde resin ("Russian Red Cement") endodontic therapy.

Science.gov (United States)

Gound, Tom G; Marx, David; Schwandt, Nathan A

2003-10-01

The purpose of this retrospective study was to evaluate the quality of treatment and incidence of flare-ups when teeth with resorcinol-formaldehyde resin are retreated in a postgraduate endodontic clinic. Fifty-eight cases were included in this study. Obturated and unfilled canal space was measured on radiographs. Forty-eight percent of the total canal space was filled before retreatment; 90% was filled after retreatment. After retreatment, obturations were rated as optimal in 59%, improved in 33%, unchanged in 6%, and worse in 2%. Seven patients (12%) had postretreatment flare-ups. Data were statistically analyzed using the Cochran-Armitage Test for Discrete Variables. No statistical difference in the incidence of flare-ups was found in teeth that before treatment had more than half the canal space filled compared to teeth with less than half, cases with pre-existing periradicular radiolucencies compared to cases with normal periradicular appearance, symptomatic cases compared to asymptomatic cases, or cases with optimal fillings after retreatment compared to less than optimal cases. It was concluded that teeth with resorcinol-formaldehyde fillings might be retreated with a good prognosis for improving the radiographic quality, but a higher than normal incidence of flare-ups may occur.

Treatment and retreatment with omalizumab in chronic spontaneous urticaria: Real life experience with twenty-five patients.

Science.gov (United States)

Türk, Murat; Yılmaz, İnsu; Bahçecioğlu, Sakine Nazik

2018-01-01

Previous data have shown the high efficacy of omalizumab in chronic spontaneous urticaria (CSU). However, factors that may be effective on the response to therapy, relapse rates after drug discontinuation, and efficacy of retreatment remain unclear. This study aimed to determine the efficacy of omalizumab in CSU refractory to conventional therapy, to identify possible factors affecting treatment response and relapse, and also to evaluate the efficacy of retreatment on relapsed disease. The data of CSU patients treated with 300 mg/month omalizumab for at least 3 months were retrospectively analyzed. In order to evaluate the efficacy of treatment and retreatment, baseline and follow-up concomitant medication score (CMS) and urticaria activity score (UAS) were calculated. Possible factors affecting treatment response and relapse were identified. Twenty-five patients were included. The median duration of omalizumab therapy was 6 (6-12) months. Of the patients with baseline UAS 6 (5.5-6) and CMS 13 (10-15), 8 (32%) had complete response (UAS = 0) and 2 (8%) were non-responders after 3 months of therapy. None of the complete responders were positive for IgG-anti-TPO. After discontinuation of omalizumab therapy, 11 (61%) patients experienced relapse and 10 of them received retreatment with omalizumab. Half of the patients had complete response, and half had partial response (UAS = 1-4) after retreatment. No treatment related adverse events were documented. Omalizumab has high efficacy in both the treatment and retreatment of CSU; however, relapse rates after discontinuation are high. Autoimmune markers may be helpful in predicting treatment response and relapse. Copyright © 2017 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

Comparison of retreatment ability of full-sequence reciprocating instrumentation and 360° rotary instrumentation.

Science.gov (United States)

Capar, Ismail Davut; Gok, Tuba; Orhan, Ezgi

2015-12-01

The purpose of the present study was to investigate the amount of root canal filling material after root canal filling removal with 360° rotary instrumentation or reciprocating motion with the same file sequence. Root canals of the 36 mandibular premolars were shaped with ProTaper Universal instruments up to size F2 and filled with corresponding single gutta-percha cone and sealer. The teeth were assigned to two retreatment groups (n = 18): group 1 360° rotational motion and group 2 reciprocating motion of ATR Tecnika motors (1310° clockwise and 578° counterclockwise). Retreatment procedure was performed with ProTaper Universal retreatment files with a sequence of D1-3 and ProTaper Universal F3 instruments. Total time required to remove filling material were recorded. Remaining filling material was examined under stereomicroscope at ×8 magnification. The data were analysed statistically using the Mann-Whitney U test, and testing was performed at 95 % confidence level (p  0.05) in terms of remaining filling material. The total time required for retreatment was shorter in 360° rotational motion group compared to reciprocating motion group (p instruments with reciprocating motion of ATR motor and conventional rotary motion have similar efficacy in root canal filling removal.

Postoperative pain after endodontic retreatment: single- versus two-visit treatment.

Science.gov (United States)

Yoldas, Oguz; Topuz, Aysin; Isçi, A Sehnaz; Oztunc, Haluk

2004-10-01

The purpose of this clinical study was to determine the effect of 1- or 2-visit root canal treatment on the postoperative pain in the retreatment cases. Two hundred eighteen cases that required retreatment were included in the study. Obturated and unfilled canal space and the status of periapical tissues were evaluated according to the PAI index. The patients were subcategorized in regard to the presence or the absence of preoperative pain. Approximately half of each category was treated in 1 appointment. After removing the previous root canal obturation materials and biomechanic preparation of root canals, the teeth in the 1-visit group were obturated at the first appointment by using AH 26 sealer and laterally compacted gutta-percha, and those in the 2-visit group were medicated with calcium hydroxide-chlorhexidine combination and then closed with a temporary filling material. One week after the initial appointment, patients were asked about the occurrence of postoperative pain. The level of discomfort was rated as no pain, mild pain, moderate pain, or severe pain (flare-up). Data were statistically analyzed using the chi-squared and Fischer exact tests. Eight patients from the 1-visit group and 2 patients from the 2-visit group had flare-ups. There was a statistical difference between the groups (P endodontic treatment with intracanal medication was found to be effective in reducing postoperative pain of previously symptomatic teeth and decreased the number of flare-ups in all retreatment cases.

Timing, cause and impact of the late Eocene stepwise sea retreat from the Tarim Basin (west China)

NARCIS (Netherlands)

Bosboom, R.|info:eu-repo/dai/nl/322947359; Dupont-Nivet, G.|info:eu-repo/dai/nl/313092559; Grothe, A.|info:eu-repo/dai/nl/338017712; Brinkhuis, H.|info:eu-repo/dai/nl/095046097; Villa, G.; Mandic, O.; Stoica, M.; Kouwenhoven, T.J.|info:eu-repo/dai/nl/191377406; Huang, W.; Yang, W.; Guo, Z.

2014-01-01

A vast shallow epicontinental sea extended across Eurasia and was well-connected to the Western Tethys before it retreated westward and became isolated as the Paratethys Sea. However, the palaeogeography and the timing of this westward retreat are too poorly constrained to determine potential wider

Evaluation of apically extruded debris during root canal retreatment with several NiTi systems.

Science.gov (United States)

Dincer, A N; Er, O; Canakci, B C

2015-12-01

To compare the amount of debris extruded apically during root canal retreatment using ProTaper, Mtwo and Reciproc instruments with hand H-files. In total, 60 freshly extracted human mandibular incisor teeth were used. All root canals were prepared with a Reciproc R25 file than filled with Gutta-percha and AH Plus sealer using cold lateral condensation before being assigned randomly to four groups (n = 15 each). In group 1, root fillings were removed with the Protaper Universal retreatment system; ProTaper Universal F3 and F4 instruments were used for the final preparation. In group 2, root fillings were removed with the Mtwo retreatment system; Mtwo size 30, .06 taper, size 35, .06 taper and size 40, .06 taper files were used for the final preparation. In group 3, root fillings were removed with Reciproc R25 instruments; Reciproc R40 instruments were used for the final preparation. In group 4, the root fillings were removed with Gates Glidden burs and sizes 35, 30 and 25 H-files; for final preparation, a size 40 H-file was used. Glass vials were used for debris collection. The vials were weighed before and after Gutta-percha removal. Additionally, the times required for the retreatment procedures were recorded. Data were analysed statistically using one-way analysis of variance. The Reciproc system produced significantly smaller amounts of apical extruded debris than the other groups (P ProTaper groups. The ProTaper and Reciproc groups required significantly less time than the Mtwo and H-file groups (P hand filing. Use of the ProTaper and Reciproc instruments required less time for retreatment procedures than use of the Mtwo or H-file. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Extensive Holocene ice sheet grounding line retreat and uplift-driven readvance in West Antarctica

Science.gov (United States)

Kingslake, J.; Scherer, R. P.; Albrecht, T.; Coenen, J. J.; Powell, R. D.; Reese, R.; Stansell, N.; Tulaczyk, S. M.; Whitehouse, P. L.

2017-12-01

The West Antarctic Ice Sheet (WAIS) reached its Last Glacial Maximum (LGM) extent 29-14 kyr before present. Numerical models used to project future ice-sheet contributions to sea-level rise exploit reconstructions of post-LGM ice mass loss to tune model parameterizations. Ice-sheet reconstructions are poorly constrained in areas where floating ice shelves or a lack of exposed geology obstruct conventional glacial-geological techniques. In the Weddell and Ross Sea sectors, ice-sheet reconstructions have traditionally assumed progressive grounding line (GL) retreat throughout the Holocene. Contrasting this view, using three distinct lines of evidence, we show that the GL retreated hundreds of kilometers inland of its present position, before glacial isostatic rebound during the Mid to Late Holocene caused the GL to readvance to its current position. Evidence for retreat and readvance during the last glacial termination includes (1) widespread radiocarbon in sediment cores recovered from beneath ice streams along the Siple and Gould Coasts, indicating marine exposure at least 200 km inland of the current GL, (2) ice-penetrating radar observations of relic crevasses and other englacial structures preserved in slow-moving grounded ice, indicating ice-shelf grounding and (3) an ensemble of new ice-sheet simulations showing widespread post-LGM retreat of the GL inland of its current location and later readvance. The model indicates that GL readvance across low slope ice-stream troughs requires uplift-driven grounding of the ice shelf on topographic highs (ice rises). Our findings highlight ice-shelf pinning points and lithospheric response to unloading as drivers of major ice-sheet fluctuations. Full WAIS collapse likely requires GL retreat well beyond its current position in the Ronne and Ross Sectors and linkage via Amundsen Sea sector glaciers.

Landmark Study Reveals Antarctic Glacier's Long History of Retreat

OpenAIRE

Kuska, Dale M.

2016-01-01

Faculty Showcase Archive Article Approved for public release; distribution is unlimited. A major study, released in late November in the journal “Nature,” reveals the history of retreat of the massive Pine Island Glacier (PIG) in western Antarctica, widely considered one of the largest contributors to global sea-level rise.

From Retreat to Re-engagement: The New American Foreign Policy ...

African Journals Online (AJOL)

From Retreat to Re-engagement: The New American Foreign Policy for ... that the re-engagement with Sub-Saharan Africa, is based on US perception of threats ... in the subordination of the region to the world's only superpower and its allies.

Long-term cliff retreat and erosion hotspots along the central shores of the Monterey Bay National Marine Sanctuary

Science.gov (United States)

Moore, Laura J.; Griggs, Gary B.

2002-01-01

Quantification of cliff retreat rates for the southern half of Santa Cruz County, CA, USA, located within the Monterey Bay National Marine Sanctuary, using the softcopy/geographic information system (GIS) methodology results in average cliff retreat rates of 7–15 cm/yr between 1953 and 1994. The coastal dunes at the southern end of Santa Cruz County migrate seaward and landward through time and display net accretion between 1953 and 1994, which is partially due to development. In addition, three critically eroding segments of coastline with high average erosion rates ranging from 20 to 63 cm/yr are identified as erosion ‘hotspots’. These locations include: Opal Cliffs, Depot Hill and Manresa. Although cliff retreat is episodic, spatially variable at the scale of meters, and the factors affecting cliff retreat vary along the Santa Cruz County coastline, there is a compensation between factors affecting retreat such that over the long-term the coastline maintains a relatively smooth configuration. The softcopy/GIS methodology significantly reduces errors inherent in the calculation of retreat rates in high-relief areas (e.g. erosion rates generated in this study are generally correct to within 10 cm) by removing errors due to relief displacement. Although the resulting root mean squared error for erosion rates is relatively small, simple projections of past erosion rates are inadequate to provide predictions of future cliff position. Improved predictions can be made for individual coastal segments by using a mean erosion rate and the standard deviation as guides to future cliff behavior in combination with an understanding of processes acting along the coastal segments in question. This methodology can be applied on any high-relief coast where retreat rates can be measured.

Non-surgical retreatment of a failed apicoectomy without retrofilling using white mineral trioxide aggregate as an apical barrier.

Science.gov (United States)

Stefopoulos, Spyridon; Tzanetakis, Giorgos N; Kontakiotis, Evangelos G

2012-01-01

Root-end resected teeth with persistent apical periodontitis are usually retreated surgically or a combination of non-surgical and surgical retreatment is employed. However, patients are sometimes unwilling to be subjected to a second surgical procedure. The apical barrier technique that is used for apical closure of immature teeth with necrotic pulps may be an alternative to non-surgically retreat a failed apicoectomy. Mineral trioxide aggregate (MTA) has become the material of choice in such cases because of its excellent biocompatibility, sealing ability and osseoinductive properties. This case report describes the non-surgical retreatment of a failed apicoectomy with no attempt at retrofilling of a maxillary central incisor. White MTA was used to induce apical closure of the wide resected apical area. Four-year follow-up examination revealed an asymptomatic, fully functional tooth with a satisfactory healing of the apical lesion. White MTA apical barrier may constitute a reliable and efficient technique to non-surgically retreat teeth with failed root-end resection. The predictability of such a treatment is of great benefit for the patient who is unwilling to be submitted to a second surgical procedure.

Summary of the RHIC Retreat 2008

International Nuclear Information System (INIS)

Pilat, F.; Brennan, M.; Brown, K.; Fischer, W.; Montag, C.

2008-01-01

The main goal of the RHIC Retreat is to review last run's performance and prepare for the next. As always though we also discussed the longer term goals and plans for the facility to put the work in perspective and in the right priority. A straw-man plan for the facility was prepared for the DOE that assumes 30 cryoweek and running 2 species per year. The plan outlines RHIC operations for 2008-2012 and integrates well accelerator and detector upgrades to optimize the physics output with high luminosities. The plans includes guidance from the PAC and has been reviewed by DOE

Observations and modeling of fjord sedimentation during the 30 year retreat of Columbia Glacier, AK

Science.gov (United States)

Love, Katherine B; Hallet, Bernard; Pratt, Thomas L.; O'Neel, Shad

2016-01-01

To explore links between glacier dynamics, sediment yields and the accumulation of glacial sediments in a temperate setting, we use extensive glaciological observations for Columbia Glacier, Alaska, and new oceanographic data from the fjord exposed during its retreat. High-resolution seismic data indicate that 3.2 × 108 m3 of sediment has accumulated in Columbia Fjord over the past three decades, which corresponds to ~5 mm a−1 of erosion averaged over the glaciated area. We develop a general model to infer the sediment-flux history from the glacier that is compatible with the observed retreat history, and the thickness and architecture of the fjord sediment deposits. Results reveal a fivefold increase in sediment flux from 1997 to 2000, which is not correlated with concurrent changes in ice flux or retreat rate. We suggest the flux increase resulted from an increase in the sediment transport capacity of the subglacial hydraulic system due to the retreat-related steepening of the glacier surface over a known subglacial deep basin. Because variations in subglacial sediment storage can impact glacial sediment flux, in addition to changes in climate, erosion rate and glacier dynamics, the interpretation of climatic changes based on the sediment record is more complex than generally assumed.

Increasing Research Productivity and Professional Development in Psychology With a Writing Retreat.

Science.gov (United States)

Stanley, Ian H; Hom, Melanie A; Chu, Carol; Joiner, Thomas E

2017-09-01

Writing is a core feature of the training requirements and career demands of psychology faculty members and graduate students. Within academic psychology, specifically, writing is vital for the generation of scientific knowledge through manuscripts and grant applications. Although resources exist regarding how to improve one's writing skills, few models have been described regarding how to promote a culture of writing productivity that realizes tangible deliverables, such as manuscripts and grant applications. In this article, we discuss the rationale, model, and initial outcome data of a writing retreat developed and implemented to increase research productivity among psychology faculty and trainees. We also review best practices for conducting writing retreats and identify key areas for future SoTL on advancing writing.

Retreatment of recanalized aneurysms after Y-stent-assisted coil embolization with double enterprise stents: case report and systematic review of the literature.

Science.gov (United States)

Kono, Kenichi; Shintani, Aki; Terada, Tomoaki

2014-01-01

It is necessary to consider possibility of recanalization and retreatment after coil embolization for cerebral aneurysms. There is concern that retreatment for recanalized aneurysms after Y-stent-assisted coil embolization may be difficult because of double stents, especially in Y-stents with double closed-cell stents owing to narrowed structures. However, no detailed reports of retreatment after Y-stent have been reported. Between July 2010 and June 2013, we treated four aneurysms with Y-stent-assisted coil embolization using Enterprise closed-cell stents. Recanalization occurred in one case (25%), and retreatment was performed. We easily navigated a microcatheter into the target portions of the aneurysm through the Y-stent and occluded the aneurysm with coils. Additionally, by systematically searching in PubMed, we found 105 cases of Y-stent-assisted coil embolization using Enterprise stents or Neuroform stents with more than 6 months of follow-up. Among them, retreatment was performed in 10 cases (9.5%). There were no significant differences in retreatment rates among different stent combinations (P=0.91; Fisher's exact test). In conclusion, navigation of a microcatheter into the aneurysm through the Y-stent with double Enterprise stents was feasible, and retreatment rates after Y-stent-assisted coiling may not depend on stent combinations.

Hillslope failure and paraglacial reworking of sediments in response to glacier retreat, Fox Valley, New Zealand.

Science.gov (United States)

McColl, Samuel T.; Fuller, Ian C.; Anderson, Brian; Tate, Rosie

2017-04-01

Climate and glacier fluctuations influence sediment supply to glacier forelands, which in turn influences down-valley hazards to infrastructure and tourism within glacier forelands. At Fox Glacier, one of New Zealand's most iconic and popular glaciers, rapid retreat has initiated a range of hillslope and valley floor responses, that present a cascade of hazards and changes that need to be carefully managed. Fox Glacier has retreated many kilometres historically, with 2.6 km of retreat since the mid-20th century, and a phase of rapid retreat of 50-340 m per year since 2009. To study the system response to past and ongoing glacial retreat at the Fox valley, morphological changes are being observed using time-lapse photography and the annual collection of high-resolution digital elevation models (DEMs) and orthophoto mosaics. The DEMs are being produced using Structure from Motion photogrammetry from UAV/RPAS and helicopter platforms, and are being used, along with manual ground surveying, to produce ground surface change models (DoDs; DEMs of Difference) and sediment budgets for the valley. Results from time-lapse photography and DoDs show that glacial retreat has initiated destabilisation and (mostly chronic) mass movement of surficial glacial sediments on the valley slopes near the glacier terminus. Alluvial fans farther down valley are actively growing, reworking glacial and landslide sediments from tributary catchments. These paraglacial sediments being delivered to the proglacial river from the glacier terminus and alluvial fans are driving aggradation of the valley floor of decimetres to metres per year and maintaining a highly dynamic braid plain. Valley floor changes also include the melting of buried dead ice, which are causing localised subsidence at the carpark and one of the alluvial fans. The unstable slopes and active debris fans, aggrading and highly active river channel, ground subsidence, add to the spectacle but also the hazards of the Fox valley

Processes controlling the retreat of the Isles Dernieres, a Louisiana barrier-island chain

Science.gov (United States)

Dingler, John R.; Reiss, Thomas E.

1991-01-01

The Isles Dernieres is a low-lying, transgressive barrier-island chain situated about 150 km west of the modern Mississippi delta. Much of the Isles Dernieres consists of highly dissected salt-marsh muds that lie at or slightly above sea level and are covered by a veneer of sand along the shoreline facing the Gulf of Mexico. Maximum berm elevations are generally less than 1.5 m above mean sea level. Since the mid-1800s, the initial island has been fragmented into four islands, and the beach face has retreated landward at a rate of more than 10 m/yr. The dominant processes controlling degradation of the chain are cold fronts that pass through the area several times each year and occasional hurricanes. Beach surveys over a 2-year period on the Isles Dernieres document irreversible beach-face retreat in conjunction with multiple cold fronts and one major hurricane (Gilbert). Although both the hurricane and the cold fronts caused the island to erode, the erosional patterns of the two storm types differed from each other. During the two years, over 60 cold fronts collectively caused about 37 m of beach-face retreat, whereas Gilbert itself produced more than 40 m of retreat. A major difference between the two storm types was in the percentage of washover sand produced by each. Commonly, the cold fronts did not create enough of a storm surge to overtop the berm, so most of the material removed from the beach face must have moved offshore or alongshore. Gilbert, in contrast, inundated the study site, and essentially all the sand removed from the beach face moved to the backshore.

Summary of the RHIC Retreat 2008

Energy Technology Data Exchange (ETDEWEB)

Pilat,F.; Brennan, M.; Brown, K.; Fischer, W.; Montag, C.

2008-08-01

The main goal of the RHIC Retreat is to review last run's performance and prepare for the next. As always though we also discussed the longer term goals and plans for the facility to put the work in perspective and in the right priority. A straw-man plan for the facility was prepared for the DOE that assumes 30 cryoweek and running 2 species per year. The plan outlines RHIC operations for 2008-2012 and integrates well accelerator and detector upgrades to optimize the physics output with high luminosities. The plans includes guidance from the PAC and has been reviewed by DOE.

Stability of therapeutic retreatment of corneal wavefront customized ablation with the SCHWIND CAM: 4-year data.

Science.gov (United States)

Aslanides, Ioannis M; Kolli, Sai; Padroni, Sara; Padron, Sara; Arba Mosquera, Samuel

2012-05-01

To evaluate the long-term outcomes of aspheric corneal wavefront ablation profiles for excimer laser retreatment. Eighteen eyes that had previously undergone LASIK or photorefractive keratectomy (PRK) were retreated with LASIK using the corneal wavefront ablation profile. Custom Ablation Manager (SCHWIND eye-tech-solutions, Kleinostheim, Germany) software and the ESIRIS flying spot excimer laser system (SCHWIND) were used to perform the ablations. Refractive outcomes and wavefront data are reported up to 4 years after retreatment. Pre- and postoperative data were compared with Student t tests and (multivariate) correlation tests. P<.05 was considered statistically significant. A bilinear correlation of various postoperative wavefront aberrations versus planned correction and preoperative aberration was performed. Mean manifest refraction spherical equivalent (MRSE) before retreatment was -0.38±1.85 diopters (D) and -0.09±0.22 D at 6 months and -0.10±0.38 D at 4 years postoperatively. The reduction in MRSE was statistically significant at both postoperative time points (P<.005). Postoperative aberrations were statistically lower (spherical aberration P<.05; coma P<.005; root-mean-square higher order aberration P<.0001) at 4 years postoperatively. Distribution of the postoperative uncorrected distance visual acuity (P<.0001) and corrected distance visual acuity (P<.01) were statistically better than preoperative values. Aspheric corneal wavefront customization with the ESIRIS yields visual, optical, and refractive results comparable to those of other wavefront-guided customized techniques for the correction of myopia and myopic astigmatism. The corneal wavefront customized approach shows its strength in cases where abnormal optical systems are expected. Systematic wavefront customized corneal ablation appears safe and efficacious for retreatment cases. Copyright 2012, SLACK Incorporated.

Variability of onset and retreat of the rainy season in mainland China and associations with atmospheric circulation and sea surface temperature

Science.gov (United States)

Cao, Qing; Hao, Zhenchun; Shao, Quanxi; Hao, Jie; Nyima, Tsring

2018-02-01

Precipitation plays an important role in both environment and human society and is a significant factor in many scientific researches such as water resources, agriculture and climate impact studies. The onset and retreat of rainy season are useful features to understand the variability of precipitation under the influence of climate change. In this study, the characteristics of onset and retreat in mainland China are investigated. The multi-scale moving t-test was applied to determine rainy season and K-means cluster analysis was used to divide China into sub-regions to better investigate rainy season features. The possible linkage of changing characteristics of onset and retreat to climate factors were also explored. Results show that: (1) the onset started from middle March in the southeast of China to early June in the northwest and rainy season ended earliest in the northwest and southeast while the central China had the latest retreat; (2) Delayed onset and advanced retreat over time were observed in many parts of China, together with overall stable or increased rainy-season precipitation, would likely lead to higher probability of flooding; (3) The onset (retreat) was associated with the increased (decreased) number of cyclones in eastern China and anticyclone near the South China Sea. Delayed onset, and advanced retreat were likely related to cold and warm sea surface temperature (SST) in the conventional El Niño-Southern Oscillation (ENSO) regions, respectively. These results suggest that predictability of rainy season can be improved through the atmospheric circulation and SST, and help water resources management and agricultural planning.

Radial Flow Effects On A Retreating Rotor Blade

Science.gov (United States)

2014-05-01

birds , marine life and even insect wings. In some cases such as helicopters, wind turbines and compres- sors, dynamic stall becomes the primary...on dynamic stall and reverse flow as applied to a helicopter rotor in forward flight and a wind turbine operating at a yaw angle. While great...occurring on a retreating blade with a focus on dynamic stall and reverse flow as applied to a helicopter rotor in forward flight and a wind turbine

Effectiveness of ProTaper, D-RaCe, and Mtwo retreatment files with and without supplementary instruments in the removal of root canal filling material.

Science.gov (United States)

Marques da Silva, B; Baratto-Filho, F; Leonardi, D P; Henrique Borges, A; Volpato, L; Branco Barletta, F

2012-10-01

To assess the efficacy of different retreatment rotary files in removing gutta-percha and endodontic sealer from canals. Ninety straight single-rooted premolars were prepared up to a size 30 and filled with gutta-percha and sealer and then randomly assigned to six retreatment groups (n = 15). Groups I, III, and V were retreated using rotary systems ProTaper Universal Retreatment (PTUR), D-RaCe, and Mtwo Retreatment, respectively. Groups II, IV, and VI were retreated using the additional instruments F4, size 40, .04 taper RaCe, and size 40, .04 taper Mtwo, respectively. The roots were split vertically, and images of the halves were obtained using a high-resolution scanner and evaluated with AutoCAD software to calculate the percentage of residual material. Data were analyzed with Kruskal-Wallis and Student-Newman-Keuls tests using a 5% significance cutoff (P 0.05) between groups when additional instruments were used. The percentage of residual material was lowest in the PTUR group and was statistically significant only when compared to the D-RaCe system (P = 0.0038). All root canals had residual filling material after retreatment even when additional instruments were used. © 2012 International Endodontic Journal.

Temperature under the Tongue: A paleotemperature record of the Drygalksi Ice Tongue with improved chronology of ice retreat

Science.gov (United States)

Subt, C.; Rosenheim, B. E.; Lee, J. I.; Yoo, K. C.; Browne, I. M.; Shevenell, A.

2017-12-01

The Ross Embayment is among the most well-studied regions in Antarctica. Despite the relative abundance of data, the style and forcing of deglaciation of the Ross Sea sector following the Last Glacial Maximum (LGM; 23-19 ka) is challenging due to the region's considerable size, complex geometry, and the difficulties in dating Antarctic glaciomarine sedimentary sequences. Ross Sea sediments indicate a dynamic glacial retreat in the western Ross Sea, whereas regional glacial systems may have retreated and advanced multiple times during the last deglaciation. Two marine sediment cores collected near the Drygalski Ice Tongue in the western Ross Sea during 2012 and 2015 Korea Polar Research Institute (KOPRI) expeditions reveal a sequence of alternating diatomaceous muds and oozes interbedded with diamict, which suggest dynamic post-LGM grounded ice retreat in the Ross Sea. Dynamic retreat is hypothesized to have been driven by rising sea levels and warmer ocean waters on the continental shelf, thus a record of upper ocean temperatures should reflect this. Here we present the first post-LGM upper ocean temperature record from the Ross Sea, developed using the TEX86 (tetraether index of lipids consisting of 86 carbons) paleothermometer. To overcome the difficulties of dating these sediments using traditional methods, we apply specialized Ramped PyrOx 14C dating for sediments with high proportions of relict carbon . This technique is particularly well-suited for the post-LGM retreat sedimentary sequences from Antarctic margins because it allows for separation of autochthonous and relict material for dating. By combining organic paleothermometry and state-of-the-art chronologic techniques, we gain a more thorough understanding of upper ocean temperatures in the Ross Sea during the last deglaciation, and their implications for ice retreat.

Effect of Endodontic Retreatment on Push-out Bond Strength and Quality of Fiber Postbonding Interface of Resin Cements.

Science.gov (United States)

Pelegrine, Rina Andréa; Paulillo, Luís Alexandre Maffei Sartini; Kato, Augusto Shoji; Fontana, Carlos Eduardo; Pinheiro, Sérgio Luiz; De Martin, Alexandre Sigrist; Bueno, Carlos Eduardo da Silveira

2016-01-01

The aim of this study is to evaluate the impact of endodontic retreatment on push-out bond strength and dentin interface of two resin cements used for fiber postcementation during endodontic retreatment. The root canals of 40 extracted human canines were prepared, obturated and divided into four groups (n = 10). Gutta-percha was partially removed and fiber posts were immediately cemented in groups 1 and 2 using Panavia F with ED Primer and RelyX™ U200, respectively. In groups 3 and 4, the root canal access was sealed with temporary restorative cement, specimens were stored for 30 days, endodontically retreated, and fiber posts were cemented using the resin cements applied to groups 1 and 2, respectively. Push-out tests and scanning electron microscopy analyses of different areas were performed. Data from push-out bond strengths were analyzed by one-way analysis of variance and Tukey's tests. Higher bond strength values were detected in the apical third for group 1 than group 3 (p 0.05). Comparisons between different thirds in the same group revealed a higher bond strength in the apical third for group 1. Scanning electron microscopy showed formation of hybrid layer and extensive resin tags in group 1. No hybrid layer was observed in groups 2 and 4. Endodontic retreatment had adverse effects on the push-out bond strength and dentinal interface of Panavia F with ED Primer when used for fiber postcementation specifically in the apical third, but not on RelyX™ U200. A significant interaction was detected between endodontic retreatment and resin cement, which indicated that endodontic retreatment might adversely affect the push-out bond strength and dentinal interface of Panavia F with ED Primer when used for fiber postcementation specifically in the apical third.

Comparison of 5468 retreatments after laser in situ keratomileusis by lifting the flap or performing photorefractive keratectomy on the flap.

Science.gov (United States)

Ortega-Usobiaga, J; Llovet-Osuna, F; Katz, T; Djodeyre, M R; Druchkiv, V; Bilbao-Calabuig, R; Baviera, J

2018-02-01

To assess visual outcomes of retreatment after laser in situ keratomileusis (LASIK) by lifting the flap or performing photorefractive keratectomy (PRK) on the flap, as well as to establish whether there was an increased risk of epithelial ingrowth (EIG) when LASIK and lifting of the flap are separated by a long time interval and to determine the incidence of corneal haze after PRK. Retrospective study of 4077 patients (5468 eyes) who underwent LASIK and subsequent retreatment were reviewed in order to study their visual results and identify cases of EIG and corneal haze. Enhancements included 5196 eyes from 3876 patients that were retreated by lifting the flap, and 272 eyes from 201 patients that were retreated by PRK on the flap. No statistically significant differences were found between the retreatments in terms of predictability, efficacy, and safety. A total of 704 cases of EIG were found after lifting the flap, for which surgical cleansing was necessary in 70. Surgical cleansing decreased the efficacy index when compared with patients with EIG who did not need cleansing (P=.01). Differences in terms of safety and predictability were not statistically significant. The incidence of corneal haze after ablation of the surface of the previous flap was 14.34%, although none of these cases were clinically relevant. Visual outcomes were similar between patients who were retreated by lifting the flap and those who underwent PRK. The incidence of EIG when the flap was lifted was 13.55%. The incidence of EIG increases with the time elapsed between the primary procedure and retreatment. Copyright © 2017 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

Writing Retreat Increases Productivity And Community For Women Geoscientists

Science.gov (United States)

O'Connell, S.; Holmes, M.

2011-12-01

Five, weeklong geoscientist writing retreats have been completed with an NSF ADANCE PAID grant. During the five nights and four and a half days, eight to twenty-four academics have gathered in a rural setting outside of Boston to get to focus on writing papers and proposals while getting to know each other. Participants range in age and experience from graduate students to emeritus professors. Over twenty papers and proposals acknowledge their production, in part to this writing retreat. Impact extends beyond papers as informal mentoring and discussions at meals and in the evenings centers on succeeding in academia. Research and teaching are foremost in the conversation. Post-docs learn strategies for applying for jobs and grants, and senior professors discuss strategies for working with academic administrations, running departments and mentoring students. They also learn new technologies and perspectives from younger participants. Particularly helpful are discussions on work-life balance. Networking opportunities extend beyond the retreat as participants join each other at their home institutions to give seminars, develop research projects and mentor each other's students. All weeks follow the same format. Participants arrive Sunday and meet during an evening welcome reception. Monday is devoted to writing. Tuesday a writing coach is available. In the morning, using examples from the scientific literature, she discusses strategies and techniques for writing clearly at a group session. During the afternoon, participants work with the coach individually or in small groups to improve their own writing projects. Wednesday evening a skill session is offered on a topic of interest. These have included undergraduate research, NSF funding, productive techniques for dealing with conflict, and generational characteristics and attitudes, which can hamper communication. A Thursday evening wrap-up session prepares participants for Friday's departure. We believe that this model

Comparison of cyclic fatigue resistance of three different rotary nickel-titanium instruments designed for retreatment.

Science.gov (United States)

Inan, Ugur; Aydin, Cumhur

2012-01-01

A number of rotary nickel-titanium (NiTi) systems have been developed to provide better, faster, and easier cleaning and shaping of the root canal system, and recently, rotary NiTi systems designed for root canal retreatment have been introduced. Because the main problem with the rotary NiTi files is fracture, the aim of this study was to compare the cyclic fatigue resistance of 3 different rotary NiTi systems designed for root canal retreatment. Total of 60 instruments of 3 different rotary NiTi systems designed for root canal retreatment were used in this study. Twenty R-Endo R3, 20 ProTaper D3, and 20 Mtwo R (Retreatment) 25.05 instruments were tested. Cyclic fatigue testing of instruments was performed by using a device that allowed the instruments to rotate freely inside an artificial canal. Each instrument was rotated until fracture occurred, and the number of cycles to fracture for each instrument was calculated. Representative samples were also evaluated under a scanning electron microscope to confirm the fracture was flexural. Data were analyzed by using 1-way analysis of variance test. R-Endo R3 instruments showed better cyclic fatigue resistance than ProTaper D3 and Mtwo R 25.05 instruments, and the difference was statistically significant (P instruments were more resistant to fatigue failure than ProTaper D3 and Mtwo R 25.05. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Recent glacier retreat and climate trends in Cordillera Huaytapallana, Peru

Science.gov (United States)

López-Moreno, J. I.; Fontaneda, S.; Bazo, J.; Revuelto, J.; Azorin-Molina, C.; Valero-Garcés, B.; Morán-Tejeda, E.; Vicente-Serrano, S. M.; Zubieta, R.; Alejo-Cochachín, J.

2014-01-01

We analyzed 19 annual Landsat Thematic Mapper images from 1984 to 2011 to determine changes of the glaciated surface and snow line elevation in six mountain areas of the Cordillera Huaytapallana range in Peru. In contrast to other Peruvian mountains, glacier retreat in these mountains has been poorly documented, even though this is a heavily glaciated area. These glaciers are the main source of water for the surrounding lowlands, and melting of these glaciers has triggered several outburst floods. During the 28-year study period, there was a 55% decrease in the surface covered by glaciers and the snowline moved upward in different regions by 93 to 157 m. Moreover, several new lakes formed in the recently deglaciated areas. There was an increase in precipitation during the wet season (October-April) over the 28-year study period. The significant increase in maximum temperatures may be related to the significant glacier retreat in the study area. There were significant differences in the wet season temperatures during El Niño (warmer) and La Niña (colder) years. Although La Niña years were generally more humid than El Niño years, these differences were not statistically significant. Thus, glaciers tended to retreat at a high rate during El Niño years, but tended to be stable or increase during La Niña years, although there were some notable deviations from this general pattern. Climate simulations for 2021 to 2050, based on the most optimistic assumptions of greenhouse gas concentrations, forecast a continuation of climate warming at the same rate as documented here. Such changes in temperature might lead to a critical situation for the glaciers of the Cordillera Huaytapallana, and may significantly impact the water resources, ecology, and natural hazards of the surrounding areas.

Postoperative Pain after Endodontic Retreatment Using Rotary or Reciprocating Instruments: A Randomized Clinical Trial.

Science.gov (United States)

Comparin, Daniel; Moreira, Edson Jorge Lima; Souza, Erick M; De-Deus, Gustavo; Arias, Ana; Silva, Emmanuel João Nogueira Leal

2017-07-01

The aim of this randomized clinical trial was to evaluate the influence of rotary or reciprocating retreatment techniques on the incidence, intensity, duration of postoperative pain, and medication intake. After power analysis calculations, 65 patients who needed endodontic retreatment were randomly assigned to 1 of 2 groups according to the instrumentation system used: Mtwo (VDW, Munich, Germany) or Reciproc (VDW). Retreatments were performed in a single visit by an endodontic specialist. Participants were asked to rate the incidence and intensity of the postoperative pain on a verbal rating scale 24, 48, and 72 hours after treatment. Patients were also asked to record the number of prescribed analgesic medication tablets (ibuprofen 400 mg) taken. A logistic regression analysis was used to assess both the incidence and duration of pain. Differences in the intensity of pain were analyzed using the ordinal (linear) chi-square test, and the Mann-Whitney U test was used to assess differences in the intake of analgesic medication between groups. No statistically significant difference was found among the 2 groups in relation to postoperative pain or analgesic medication intake at the 3 time points assessed (P > .05). Multivariate analysis showed a significantly higher incidence of pain after 24 hours when preoperative pain was present and a significantly longer duration of pain for men than women independently of the retreatment technique used. The reciprocating system and the continuous rotary system were found to be equivalent regarding the incidence, intensity, duration of postoperative pain, and intake of analgesic medication. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

From networking to next-working: how an academic department "retreated" and advanced at the same time.

Science.gov (United States)

Yager, Joel; Kenna, Heather; Hantke, Mindy

2015-04-01

Department-wide retreats conducted at periods of transition can enrich and benefit academic departments in several ways. Here, the authors describe the organization, conduct, and immediate outcomes of a department-wide retreat in a university department of psychiatry intended to (1) foster networking and communication among faculty who often work in "silos" and (2) invite the faculty to provide "internal consultations" regarding aspirational strategic goals and recommendations for short-term actionable tactics to address these goals. The retreat featured an evening networking and socializing poster session followed by a day-long event consisting of small group and large group interactive sessions. Participants were 120 faculty members including 44 new and younger faculty members who prepared and presented posters about themselves and their work. A variety of aspirational goals and specific recommendations for follow-up emerged from small groups were discussed in plenary sessions and were subsequently summarized and distributed to the faculty to be addressed by ongoing workgroups. Immediate informal feedback suggests that conducting and acting on recommendations ensuing from academic department retreats can foster at least a short-term sense of shared community and purpose, network faculty, identify commonly held values and aspirational goals, and potentially stimulate formation of innovative affinity groups and collaborations. Longer-term workgroup efforts and outcome assessments are required to assess the enduring results and value of such undertakings.

Glacier retreat and associated sediment dynamics in proglacial areas: a case study from the Silvretta Alps, Austria

Science.gov (United States)

Felbauer, Lucia; Pöppl, Ronald

2016-04-01

Global warming results in an ongoing retreat of glaciers in the Alps, leaving behind large amounts of easily erodible sediments. In addition, the debuttressing of rock-walls and the decay of permafrost in the high mountain regions facilitates mass movements of potential disastrous consequences, such as rock falls, landslides and debris flows. Therefore, it is highly important to quantify the amount of sediments that are supplied from the different compartments and to investigate how glacial retreat influences sediment dynamics in proglacial areas. In the presented work glacier retreat and associated sediment dynamics were investigated in the Kromer valley (Silvretta Alps, Austria) by analyzing remote sensing data. Glacial retreat from the period of 1950 to 2012 was documented by interpreting aerial photographs. By digitizing the different stages of the glaciers for six time frames, changes in glacier area and length were mapped and quantified. In order to identify, characterize and quantify sediment dynamics in the proglacial areas a high resolution DEM of difference (DoD) between 2007 and 2012 was created and analyzed, further differentiating between different zones (e.g. valley bottom, hillslope) and types of geomorphic processes (e.g. fluvial, gravitational). First results will be presented at the EGU General Assembly 2016.

Radioiodine uptake following iodine-131 therapy for Graves' disease: an early indicator of need for retreatment

International Nuclear Information System (INIS)

Carpentier, W.R.; Gilliland, P.F.; Piziak, V.K.; Petty, F.C.; McConnell, B.G.; Verdonk, C.A.; Ibarra, J.D.; Thompson, J.Q.

1989-01-01

Forty-five patients with Graves' disease were studied prospectively to determine if 24-hour I-131 uptake measurements alone or in combination with serum thyroid hormone levels at six weeks would determine the necessity for retreatment of the thyrotoxicosis. All patients with an I-131 uptake greater than 30% at six weeks required retreatment. No patient with an I-131 uptake of less than 15% required retreatment. Patients with uptakes between 15% and 30% were variable. An elevated free thyroxin index at 6 weeks is not helpful to determine which patients will remain thyrotoxic. Patients with a free thyroxin index within the normal range at six weeks can be predicted to be euthyroid by 12 weeks if their 24-hour I-131 uptake is between 15% and 30% and to be hypothyroid if their 24-hour I-131 uptake is below 15%. There was no difference between patient groups treated initially with antithyroid medication and those who were not

Incidence of apical crack initiation and propagation during the removal of root canal filling material with ProTaper and Mtwo rotary nickel-titanium retreatment instruments and hand files.

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Topçuoğlu, Hüseyin Sinan; Düzgün, Salih; Kesim, Bertan; Tuncay, Oznur

2014-07-01

The aim of this study was to determine the incidence of crack initiation and propagation in apical root dentin after retreatment procedures performed by using 2 rotary retreatment systems and hand files with additional instrumentation. Eighty extracted mandibular premolars with single canals were selected. One millimeter from the apex of each tooth was ground perpendicular to the long axis of the tooth, and the apical surface was polished. Twenty teeth served as the control group, and no preparation was performed. The remaining 60 teeth were prepared to size 35 with rotary files and filled with gutta-percha and AH Plus sealer. Specimens were then divided into 3 groups (n = 20), and retreatment procedures were performed with the following devices and techniques: ProTaper Universal retreatment files, Mtwo retreatment files, and hand files. After retreatment, the additional instrumentation was performed by using size 40 ProTaper, Mtwo, and hand files. Digital images of the apical root surface were recorded before preparation, after instrumentation, after filling, after retreatment, and after additional instrumentation. The images were then inspected for the presence of any new apical cracks and propagation. Data were analyzed with the logistic regression and Fisher exact tests. All experimental groups caused crack initiation and propagation after use of retreatment instruments. The ProTaper and Mtwo retreatment groups caused greater crack initiation and propagation than the hand instrument group (P ProTaper and Mtwo instruments after the use of retreatment instruments caused crack initiation and propagation, whereas hand files caused neither crack initiation nor propagation (P < .05). This study showed that retreatment procedures and additional instrumentation after the use of retreatment files may cause crack initiation and propagation in apical dentin. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

In vitro evaluation of the effectiveness of ProTaper universal rotary retreatment system for gutta-percha removal with or without a solvent.

Science.gov (United States)

Takahashi, Cristiane Midori; Cunha, Rodrigo Sanches; de Martin, Alexandre Sigrist; Fontana, Carlos Eduardo; Silveira, Cláudia Fernandes M; da Silveira Bueno, Carlos Eduardo

2009-11-01

Effective removal of gutta-percha in endodontic retreatment is a significant factor to ensure a favorable outcome from failed procedures. The purpose of this study was to evaluate the efficacy of a nickel-titanium rotary instrument system with or without a solvent versus stainless steel hand files for gutta-percha removal. Forty extracted human maxillary anterior teeth were prepared and filled. They were divided into 4 groups: Gates-Glidden and K-files, Gates-Glidden and K-files with chloroform, ProTaper Universal rotary retreatment system, and ProTaper Universal rotary retreatment system with chloroform. The operating time was recorded. The teeth were longitudinally sectioned and photographed. The images were analyzed and the filling remnants were quantified by using the IMAGE TOOL software. With Kruskall-Wallis test, statistical analysis showed that there was no significant difference between the techniques in regard to the amount of the endodontic filling remnants (P ProTaper Universal rotary retreatment system was faster than the hand files (P ProTaper Universal rotary retreatment system without chloroform was faster.

Efficacy of ProTaper Retreatment System in Root Canals Obturated with Gutta-Percha Using Two Different Sealers and GuttaFlow

Science.gov (United States)

Siotia, Jaya; Acharya, Shashi Rashmi; Gupta, Sunil Kumar

2011-01-01

Objective. To compare the efficacy of ProTaper retreatment files in removing three different obturating materials. Study Design. Forty-five human, single-rooted premolars were divided into three experimental groups. Group 1 was obturated with gutta-percha and AH Plus sealer, Group 2 was obturated with gutta-percha and zinc oxide eugenol sealer, and Group 3 was obturated with GuttaFlow. Retreatment was done using the ProTaper universal rotary retreatment files. Root halves were visualized using magnifying loops at 3X magnification and optical stereomicroscope at 10X magnification. Images were analyzed using AutoCAD 2004 software to calculate area of the remaining debris in the canal. For statistical analysis were used variance test and ANOVA. Results. Total debris/canal area ratio between the three groups showed a statistically significant difference (P < 0.001). Conclusion. ProTaper retreatment system did not produce completely clean canals in any of the groups. However, it had the best efficacy towards removing silicon based obturating material GuttaFlow. PMID:22114598

Decision logic for retreatment of asymptomatic lung cancer recurrence based on positron emission tomography findings

International Nuclear Information System (INIS)

Frank, Albert; Lefkowitz, David; Jaeger, Stanley; Gobar, Lisa; Sunderland, John; Gupta, Naresh; Scott, Walter; Mailliard, James; Lynch, Henry; Bishop, John; Thorpe, Patricia; Dewan, Naresh

1995-01-01

Purpose: The purpose of the study was to determine if Positron emission tomography (PET) 2-[F-18] fluoro-2-deoxy-D-glucose (FDG) imaging could detect subclinical local lung cancer recurrence and whether retreatment of such recurrence was feasible and beneficial. Methods and Materials: Twenty patients with biopsy proven lung cancer were studied with Positron emission tomography for the purpose of detecting subclinical lung cancer recurrence over a period of 4.25 years. All patients were treated with external radiation as part or all of their therapy. Twenty patients had baseline PET and computed tomography (CT) studies for comparison with later studies. Surviving patients had a total of 40 sequential PET scans and 35 CT scans. The follow-up interval ranged from 5 to 40 months posttreatment. The differential uptake ratio (DUR) was determined for regions of interest of increased FDG uptake. Results: The median DUR value of the 20 baseline PET studies was 5.59. The DUR value of greater than 3 was empirically selected as being positive for tumor detection. On baseline studies, PET had a 100% correlation with the CT findings in regard to detection of the site of primary tumor involvement. Four of 20 patients showed areas of discordance in the mediastinal and hilar areas on initial PET and CT studies. Seven of 17 patients showed discordant posttreatment PET-CT findings. Two false positive PET studies were due to radiation pneumonitis and one to macrophage glycolysis in tumor necrosis. For detection of asymptomatic tumor recurrence, analysis of sequential PET and CT studies, biopsy results, and the patient's clinical course suggested that PET had a sensitivity of 100%, specificity of 89.3%, and accuracy of 92.5%. Computerized Tomography was found to have a sensitivity of 67%, specificity of 85%, and accuracy of 82% for detection of such early-stage recurrence. Five patients went on to have retreatment with external irradiation based upon the PET evidence. Four retreated

Endodontic retreatment: clinical comparison of reciprocating systems versus rotary system in disinfecting root canals.

Science.gov (United States)

Martinho, Frederico C; Freitas, Lilian F; Nascimento, Gustavo G; Fernandes, Aleteia M; Leite, Fabio R M; Gomes, Ana P M; Camões, Izabel C G

2015-07-01

This clinical study was conducted to compare the effectiveness of single-file reciprocating systems and rotary systems in removing endotoxins and cultivable bacteria in endodontic retreatment. Thirty endodontically treated teeth with post-treatment apical periodontitis were selected. The specimens were divided into three groups according to the system used: WaveOne (n = 10), Reciproc instrument (n = 10), and ProTaper Universal Retreatment system (n = 10). Samples were collected before and after chemomechanical preparation. The irrigation was performed by using 2.5% sodium hypochlorite. A chromogenic limulus amebocyte lysate assay test was used to quantify endotoxins. Culture techniques were used to determine bacterial colony-forming unit counts. At baseline, endotoxins and cultivable bacteria were recovered from 100% of the root canal samples in a median value of 5.84 EU/mL and 4.98 × 10(3) CFU/mL, respectively. After CMP, no differences were found in the median percentage values of endotoxin reduction achieved with reciprocating systems-WaveOne [94.11%] and Reciproc [93.29%] and with rotary systems-ProTaper [94.98%] (P > 0.05). Both single-file reciprocating systems [WaveOne (98.27%) and Reciproc (99.54%)] and rotary system [ProTaper (98.73%)] were effective in reducing bacterial load (P > 0.05). Moreover, no differences were found among the systems tested. The Reciproc and WaveOne reciprocating systems were as effective as the ProTaper system for removal of endotoxins and bacteria in endodontic retreatment. All systems tested were effective to remove cultivable bacteria and endotoxin in endodontic retreatment. As no differences among systems were observed, it is possible to suggest that clinicians should choose the preferred technique to perform endodontic.

Bathymetry and retreat of Southeast Greenland glaciers from Operation IceBridge and Ocean Melting Greenland data

Science.gov (United States)

Millan, R.; Rignot, E. J.; Morlighem, M.; Bjork, A. A.; Mouginot, J.; Wood, M.

2017-12-01

Southeast Greenland has been one of the largest contributors to ice mass loss in Greenland in part because of significant changes in glacier dynamics. The leading hypothesis for the changes in glacier dynamics is that enhanced thermal forcing from the ocean has dislodged a number of glaciers from their anchoring positions and some of them retreated rapidly along a reverse bed. The glaciers response has been observed to vary significantly from one fjord to the next, but until now there was not enough data to understand or interpret these changes. In particular, there was no data on glacier bed topography and seafloor bathymetry in the fjords. Here we present the results of new fjord mapping by the NASA Ocean Melting Greenland mission combined with a recent high-resolution airborne gravity survey by NASA Operation IceBridge. We combine these data with a reconstruction of the bed using a mass conservation approach upstream extending into the glacial fjords for the first time. In the fjord and along the ice-ocean transition, we employ a 3D inversion of gravity data to infer the bed elevation along a set of 9 survey boxes spanning south of Helheim Glacier to the southern tip of Southeast Greenland. We combine the results with an analysis of the glacier front history since the 1930's and Conductivity Temperature Depth data obtained in the fjord by OMG in 2016. The data reveals bed elevations several 100-m deeper than previously thought, for almost all the glaciers, up to 500 m for some of them. For many glaciers, the bed profiles help to completely understand the history of retreat of the glaciers. For instance, glaciers stranded on sills have been stable; glaciers on a reverse slope have retreated rapidly; and glaciers with a normal slope have retreated slowly. The mapping also helps document the extent of the marine portion of the glacier basins. In many of the fjords, we document the presence of warm, salty Atlantic Water which fuels large melt rates. We employ

Panretinal photocoagulation versus intravitreal injection retreatment pain in high-risk proliferative diabetic retinopathy

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Célia Regina Farias de Araújo Lucena

2013-02-01

Full Text Available PURPOSE: To compare pain related to intravitreal injection and panretinal photocoagulation in the management of patients with high-risk proliferative diabetic retinopathy. METHODS: Prospective study including patients with high-risk proliferative diabetic retinopathy and no prior laser treatment randomly assigned to receive panretinal photocoagulation (PRP group or panretinal photocoagulation plus intravitreal ranibizumab (PRPplus group. In all patients, panretinal photocoagulation was administered in two sessions (weeks 0 and 2, and intravitreal ranibizumab was administered at the end of the first laser session in the PRPplus group. Retreatment was performed at weeks 16 and 32 if active new vessels were detected at fluorescein angiography. Patients in the PRPplus group received intravitreal ranibizumab and patients in the PRP group received 500-µm additional spots per quadrant of active new vessels. After the end of retreatment, a 100-degree Visual Analog Scale was used for pain score estimation. The patient was asked about the intensity of pain during the whole procedure (retinal photocoagulation session or intravitreal ranibizumab injection. Statistics for pain score comparison were performed using a non-parametric test (Wilcoxon rank sums. RESULTS: Seventeen patients from PRPplus and 14 from PRP group were evaluated for pain scores. There were no significant differences between both groups regarding gender, glycosylated hemoglobin and disease duration. Mean intravitreal injection pain (±SEM was 4.7 ± 2.1 and was significantly lower (p<0.0001 than mean panretinal photocoagulation pain (60.8 ± 7.8. Twelve out of 17 patients from the PRPplus group referred intensity pain score of zero, while the minimal score found in PRP group was found in one patient with 10.5. CONCLUSION: In patients with high-risk proliferative diabetic retinopathy who needed retreatment for persistent new vessels, there was more comfort for the patient when retreatment

Root Canal Retreatment menggunakan Kombinasi Kalsium Hidroksida dan Chlorhexidine sebagai Medikamen Intra Kanal Insisivus Sentral Kiri Maksila

Directory of Open Access Journals (Sweden)

Andina Novita Sari

2014-12-01

retreatment dengan cleaning dan shaping ulang yang baik dengan menggunakan medikasi intrakanal berupa kombinasi kalsium hidroksida dan chlorhexidine 2% diharapkan mempunyai efek antimikroba yang sinergis untuk mencapai kesuksesan root canal retreatment.   Root Canal Retreatment Using Calcium Hydroxide as Intra Canal Medicament On The Maxillary Left Incisor. Enterococcus faecalis bacteria is most abundant in the root canal infection treated endodontically. Chlorhexidine has a broad antibacterial spectrum and has been used as an endodontic irrigant and intracanal medication. Chlorhexidine has a bactericidal and fungicidal effect as chlorhexidine absorbed into the bacterial cell surface and cause damage to the integrity of the cell membrane. Calcium hydroxide is a biocompatible, antimicrobial agents with high pH effects and stimulates hard tissue formation. A mixture of calcium hydroxide and chlorhexidine is used to control bacteria Enterococcus faecalis alternative. The purpose of this case report is to report on the success of root canal treatment in the left maxillary central incisor with acute periapical periodontitis using a combination of calcium hydroxide and chlorhexidine as intracanal A 24 years old female patient presents with left upper central incisor tooth ache since 4 years ago. The tooth was hurt to percussion, but normal to pulpation as well as the mobility. The tooth has a history of previous trauma and broken 6 years ago and has performed endodontic treatment. Radiographic examination showed obturation teeth 21 are not hermetic with periapical radiolucency in diffuse boundaries, widening of the periodontal ligament and the dissolution of the lamina dura. Root canal re-treatment using a combination of calcium hydroxide and chlorhexidine as intracanal medicaments were performed. In conclussion, the root canal cleaning and shaping retreatment can be performed using a combination of calcium hydroxide and chlorhexidine as intracanal

The Multitrophic Effects of Climate Change and Glacier Retreat in Mountain Rivers.

Science.gov (United States)

Fell, Sarah C; Carrivick, Jonathan L; Brown, Lee E

2017-10-01

Climate change is driving the thinning and retreat of many glaciers globally. Reductions of ice-melt inputs to mountain rivers are changing their physicochemical characteristics and, in turn, aquatic communities. Glacier-fed rivers can serve as model systems for investigations of climate-change effects on ecosystems because of their strong atmospheric-cryospheric links, high biodiversity of multiple taxonomic groups, and significant conservation interest concerning endemic species. From a synthesis of existing knowledge, we develop a new conceptual understanding of how reducing glacier cover affects organisms spanning multiple trophic groups. Although the response of macroinvertebrates to glacier retreat has been well described, we show that there remains a relative paucity of information for biofilm, microinvertebrate, and vertebrate taxa. Enhanced understanding of whole river food webs will improve the prediction of river-ecosystem responses to deglaciation while offering the potential to identify and protect a wider range of sensitive and threatened species.

The retreat of the world's mountain glaciers during recent decades

International Nuclear Information System (INIS)

Francou, B.; Vincent, Ch.

2009-01-01

Glaciers have become essential tools for measuring changes in the global environment. Here, we analyze glacier evolution during the last few decades and we wonder whether the observed retreat remains in the range of glacier fluctuations since the mid-Holocene. The main fluctuations experienced by glaciers during the last millenniums, and particularly during the Little Ice Age (-1300 A.D. to ∼1860 A.D.), are presented succinctly. The recent 1960-2005 period, well documented both by ground and remote sensing observations, shows important disparities between different massifs concerning the timing and the magnitude of glacier fluctuations, which depend on regional climatic conditions. The links between glacier mass balance evolution and climate is clear when approached from an energy balance but the variables commonly considered are only temperature and precipitation. The strong correlation existing between these variables and the mass balance evolution makes it possible to simulate glaciers in the future in function of distinct climatic scenarios. Modeling glacier retreat for the 21. century is an important goal because it will allow the impacts on water resource and sea level to be assessed. (authors)

Skin-deep diagnosis: affective bias and zebra retreat complicating the diagnosis of systemic sclerosis.

Science.gov (United States)

Miller, Chad S

2013-01-01

Nearly half of medical errors can be attributed to an error of clinical reasoning or decision making. It is estimated that the correct diagnosis is missed or delayed in between 5% and 14% of acute hospital admissions. Through understanding why and how physicians make these errors, it is hoped that strategies can be developed to decrease the number of these errors. In the present case, a patient presented with dyspnea, gastrointestinal symptoms and weight loss; the diagnosis was initially missed when the treating physicians took mental short cuts and used heuristics as in this case. Heuristics have an inherent bias that can lead to faulty reasoning or conclusions, especially in complex or difficult cases. Affective bias, which is the overinvolvement of emotion in clinical decision making, limited the available information for diagnosis because of the hesitancy to acquire a full history and perform a complete physical examination in this patient. Zebra retreat, another type of bias, is when a rare diagnosis figures prominently on the differential diagnosis but the physician retreats for various reasons. Zebra retreat also factored in the delayed diagnosis. Through the description of these clinical reasoning errors in an actual case, it is hoped that future errors can be prevented or inspiration for additional research in this area will develop.

Improved age constraints for the retreat of the Irish Sea Ice Stream

Science.gov (United States)

Smedley, Rachel; Chiverrell, Richard; Duller, Geoff; Scourse, James; Small, David; Fabel, Derek; Burke, Matthew; Clarke, Chris; McCarroll, Danny; McCarron, Stephen; O'Cofaigh, Colm; Roberts, David

2016-04-01

BRITICE-CHRONO is a large (> 45 researchers) consortium project working to provide an extensive geochronological dataset constraining the rate of retreat of a number of ice streams of the British-Irish Ice Sheet following the Last Glacial Maximum. When complete, the large empirical dataset produced by BRITICE-CHRONO will be integrated into model simulations to better understand the behaviour of the British-Irish Ice Sheet in response to past climate change, and provide an analogue for contemporary ice sheets. A major feature of the British-Irish Ice Sheet was the dynamic Irish Sea Ice Stream, which drained a large proportion of the ice sheet and extended to the proposed southern limit of glaciation upon the Isles of Scilly (Scourse, 1991). This study will focus on a large suite of terrestrial samples that were collected along a transect of the Irish Sea basin, covering the line of ice retreat from the Isles of Scilly (50°N) in the south, to the Isle of Man (54°N) in the north; a distance of 500 km. Ages are determined for both the eastern and western margins of the Irish Sea using single-grain luminescence dating (39 samples) and terrestrial cosmogenic nuclide dating (10 samples). A Bayesian sequence model is then used in combination with the prior information determined for deglaciation to integrate the geochronological datasets, and assess retreat rates for the Irish Sea Ice Stream. Scourse, J.D., 1991. Late Pleistocene stratigraphy and palaeobotany of the Isles of Scilly. Philosophical Transactions of the Royal Society of London B334, 405 - 448.

Modelling Waterfall Retreat in Heterogenous Bedrock

Science.gov (United States)

Attal, M.; Hodge, R. A.; Williams, R.; Baynes, E.

2016-12-01

Bedrock rivers are the mediators of environmental change through mountainous landscapes. In response to an increase in uplift rate for example, a "knickpoint" (often materialised as a waterfall) will propagate upstream, separating a domain downstream where the river and its adjacent hillslopes have steepened in response to the change from a "relict" domain upstream which is adjusted to the conditions before the change (Crosby and Whipple 2006). Many studies assume that knickpoint propagation rate scales with drainage area, based on the stream power theory. However, recent studies in a range of locations have found no obvious relationship between knickpoint retreat rate and drainage area, potentially resulting from the stream power law neglecting (i) the influence of sediment on the processes associated with waterfall migration and (ii) thresholds for bedrock detachment (Cook et al. 2013; Mackey et al. 2014; DiBiase et al. 2015; Baynes et al. 2015; Brocard et al. 2016). In this study, we develop a 1D model of waterfall retreat in horizontally bedded bedrock with varying joint spacing. In the model, knickpoint migration is based on two rules: a waterfall will start migrating once the threshold flow depth (a function of knickpoint height and joint spacing) has been exceeded (Lamb and Dietrich 2009), and the migration rate will then be a function of the water-depth-to-waterfall-height ratio, based on experimental results by Baynes (2015). Using a hydrograph based on a Poisson rectangular pulse rainfall simulator (Tucker and Bras 2001), we demonstrate the importance of structure in controlling the speed at which waterfalls migrate but also their number and the length over which they are distributed (Fig. 1). The model is applied to the Jökulsá á Fjöllum, NE Iceland, where rapid migration of waterfalls as a result of discrete events has been identified (Baynes et al. 2015), using new constraints on joint spacing derived from high resolution lidar survey of the gorge

ACL Research Retreat VI : An update on ACL injury risk and prevention

NARCIS (Netherlands)

R.J. Schmitz; M. Collins; D.A. Padua; Anne Benjaminse; A.M. Chaudhari; S.J. Schultz

2012-01-01

It has been well recognized that multiple factors, whether individually or in combination, contribute to noncontact anterior cruciate ligament (ACL) injury. The ongoing mission of the ACL Research Retreat is to bring clinicians and researchers together to present and discuss the most recent advances

Probabilistic estimation of dune retreat on the Gold Coast, Australia

Science.gov (United States)

Palmsten, Margaret L.; Splinter, Kristen D.; Plant, Nathaniel G.; Stockdon, Hilary F.

2014-01-01

Sand dunes are an important natural buffer between storm impacts and development backing the beach on the Gold Coast of Queensland, Australia. The ability to forecast dune erosion at a prediction horizon of days to a week would allow efficient and timely response to dune erosion in this highly populated area. Towards this goal, we modified an existing probabilistic dune erosion model for use on the Gold Coast. The original model was trained using observations of dune response from Hurricane Ivan on Santa Rosa Island, Florida, USA (Plant and Stockdon 2012. Probabilistic prediction of barrier-island response to hurricanes, Journal of Geophysical Research, 117(F3), F03015). The model relates dune position change to pre-storm dune elevations, dune widths, and beach widths, along with storm surge and run-up using a Bayesian network. The Bayesian approach captures the uncertainty of inputs and predictions through the conditional probabilities between variables. Three versions of the barrier island response Bayesian network were tested for use on the Gold Coast. One network has the same structure as the original and was trained with the Santa Rosa Island data. The second network has a modified design and was trained using only pre- and post-storm data from 1988-2009 for the Gold Coast. The third version of the network has the same design as the second version of the network and was trained with the combined data from the Gold Coast and Santa Rosa Island. The two networks modified for use on the Gold Coast hindcast dune retreat with equal accuracy. Both networks explained 60% of the observed dune retreat variance, which is comparable to the skill observed by Plant and Stockdon (2012) in the initial Bayesian network application at Santa Rosa Island. The new networks improved predictions relative to application of the original network on the Gold Coast. Dune width was the most important morphologic variable in hindcasting dune retreat, while hydrodynamic variables, surge and

Healing the heart: a randomized pilot study of a spiritual retreat for depression in acute coronary syndrome patients.

Science.gov (United States)

Warber, Sara L; Ingerman, Sandra; Moura, Vera L; Wunder, Jenna; Northrop, Alyssa; Gillespie, Brenda W; Durda, Kate; Smith, Katherine; Rhodes, Katherine S; Rubenfire, Melvyn

2011-01-01

Depression is associated with increased risk of cardiovascular morbidity and mortality in coronary heart disease. Numerous conventional and complementary therapies may address depression. Few involving spirituality have been tested. The aim of this study was to compare the effects of a nondenominational spiritual retreat, Medicine for the Earth (MFTE), on depression and other measures of well-being six- to 18-months post acute coronary syndrome (ACS). A randomized controlled pilot study of MFTE, Lifestyle Change Program (LCP), or usual cardiac care (control) was conducted in Southeastern Michigan. ACS patients were recruited via local and national advertising (n = 58 enrolled, 41 completed). The four-day MFTE intervention included guided imagery, meditation, drumming, journal writing, and nature-based activities. The four-day LCP included nutrition education, exercise, and stress management. Both retreat groups received follow-up phone coaching biweekly for three months. Validated self-report scales of depression, spiritual well-being, perceived stress, and hope were collected at baseline, immediately post-retreat, and at three and six months. Depression was not significantly different among groups (P = .21). However, the MFTE group had the highest depression scores at baseline and had significantly lower scores at all postintervention time points (P ≤ .002). Hope significantly improved among MFTE participants, an effect that persisted at three- and six-month follow-up (P = .014). Although several measures showed improvement in all groups by six months, the MFTE group had immediate improvement post-retreat, which was maintained. This pilot study shows that a nondenominational spiritual retreat, MFTE, can be used to increase hope while reducing depression in patients with ACS. Copyright © 2011 Elsevier Inc. All rights reserved.

Radioiodine uptake following iodine-131 therapy for Graves' disease: an early indicator of need for retreatment

Energy Technology Data Exchange (ETDEWEB)

Carpentier, W.R.; Gilliland, P.F.; Piziak, V.K.; Petty, F.C.; McConnell, B.G.; Verdonk, C.A.; Ibarra, J.D.; Thompson, J.Q.

1989-01-01

Forty-five patients with Graves' disease were studied prospectively to determine if 24-hour I-131 uptake measurements alone or in combination with serum thyroid hormone levels at six weeks would determine the necessity for retreatment of the thyrotoxicosis. All patients with an I-131 uptake greater than 30% at six weeks required retreatment. No patient with an I-131 uptake of less than 15% required retreatment. Patients with uptakes between 15% and 30% were variable. An elevated free thyroxin index at 6 weeks is not helpful to determine which patients will remain thyrotoxic. Patients with a free thyroxin index within the normal range at six weeks can be predicted to be euthyroid by 12 weeks if their 24-hour I-131 uptake is between 15% and 30% and to be hypothyroid if their 24-hour I-131 uptake is below 15%. There was no difference between patient groups treated initially with antithyroid medication and those who were not.

Risk factors for treatment default among re-treatment tuberculosis patients in India, 2006.

Science.gov (United States)

Jha, Ugra Mohan; Satyanarayana, Srinath; Dewan, Puneet K; Chadha, Sarabjit; Wares, Fraser; Sahu, Suvanand; Gupta, Devesh; Chauhan, L S

2010-01-25

Under India's Revised National Tuberculosis Control Programme (RNTCP), >15% of previously-treated patients in the reported 2006 patient cohort defaulted from anti-tuberculosis treatment. To assess the timing, characteristics, and risk factors for default amongst re-treatment TB patients. For this case-control study, in 90 randomly-selected programme units treatment records were abstracted from all 2006 defaulters from the RNTCP re-treatment regimen (cases), with one consecutively-selected non-defaulter per case. Patients who interrupted anti-tuberculosis treatment for >2 months were classified as defaulters. 1,141 defaulters and 1,189 non-defaulters were included. The median duration of treatment prior to default was 81 days (25%-75% interquartile range 44-117 days) and documented retrieval efforts after treatment interruption were inadequate. Defaulters were more likely to have been male (adjusted odds ratio [aOR] 1.4, 95% confidence interval [CI] 1.2-1.7), have previously defaulted anti-tuberculosis treatment (aOR 1.3 95%CI 1.1-1.6], have previous treatment from non-RNTCP providers (AOR 1.3, 95%CI 1.0-1.6], or have public health facility-based treatment observation (aOR 1.3, 95%CI 1.1-1.6). Amongst the large number of re-treatment patients in India, default occurs early and often. Improved pre-treatment counseling and community-based treatment provision may reduce default rates. Efforts to retrieve treatment interrupters prior to default require strengthening.

Linking Backbarrier Lacustrine Stratigraphy with Spatial Dynamics of Shoreline Retreat in a Rapidly Subsiding Region of the Mississippi River Delta

Science.gov (United States)

Dietz, M.; Liu, K. B.; Bianchette, T. A.; Yao, Q.

2017-12-01

The shoreline along the northern Gulf of Mexico is rapidly retreating as coastal features of abandoned Mississippi River delta complexes erode and subside. Bay Champagne is located in the Caminada-Moreau headland, a region of shoreline west of the currently active delta that has one of the highest rates of retreat and land loss. As a result, this site has transitioned from a stable, circular inland lake several kilometers from the shore to a frequently perturbed, semi-circular backbarrier lagoon, making it ideal to study the environmental effects of progressive land loss. Analyses of clastic layers in a series of sediment cores collected at this site over the past decade indicate the lake was less perturbed in the past and has become increasingly more sensitive to marine incursion events caused by tropical cyclones. Geochemical and pollen analyses of these cores also reveal profound changes in environmental and chemical conditions in Bay Champagne over the past century as the shoreline has retreated. Through relating stratigraphy to spatial changes observed from satellite imagery, this study attempts to identify the tipping point at which Bay Champagne began the transition from an inland lake to a backbarrier environment, and to determine the rate at which this transition occurred. Results will be used to develop a model of the environmental transition experienced by a rapidly retreating coastline and to predict how other regions of the Mississippi River deltaic system could respond to future shoreline retreat.

The use of social Stegodyphus spider retreats as nest-lining by pale ...

African Journals Online (AJOL)

The pale chanting-goshawk (Melierax canorus) incorporates silk nests (hereafter 'retreats') of the social spider Stegodyphus dumicola (Araneae: Eresidae) in the construction of the nest-lining of their own nests. This study investigates whether pale chanting-goshawks in the Little Karoo, South Africa, show a preference for ...

Interest in health promotion among Korean American Seventh-day Adventists attending a religious retreat.

Science.gov (United States)

Jo, Angela M; Maxwell, Annette E; Choi, Sunhye; Bastani, Roshan

2012-01-01

Little is known about interest in faith-based health promotion programs among Asian American populations. Among the Christian denominations, the Seventh-day Adventist (SDA) church is known to place a strong doctrinal emphasis on health. To understand appropriate ways to develop and implement health promotion programs and to conduct research among Korean American SDAs. We collaborated with the North American Division of Korean SDA Churches which sponsors annual week-long religious retreats for their church members. We developed and administered a 10-page questionnaire at their 2009 retreat in order to assess socio-demographic and church characteristics, religiosity, perceived relationship between health and religion, and interest and preferences for church-based health promotion programs. Overall, 223 participants completed our survey (123 in Korean and 100 in English). The sample consisted of regular churchgoers who were involved in a variety of helping activities, and many holding leadership positions in their home churches. The vast majority was interested in receiving health information at church (80%) in the form of seminars, cooking classes and workshops (50-60%). Fewer respondents were interested in support groups (27%). Some interests and preferences differed between English and Korean language groups. Korean American SDA church retreat participants from a large geographic area are very interested in receiving health information and promoting health at their churches and can potentially serve as "agents of influence" in their respective communities.

Yoga, Meditation and Mind-Body Health: Increased BDNF, Cortisol Awakening Response, and Altered Inflammatory Marker Expression after a 3-Month Yoga and Meditation Retreat

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B. Rael Cahn

2017-06-01

Full Text Available Thirty-eight individuals (mean age: 34.8 years old participating in a 3-month yoga and meditation retreat were assessed before and after the intervention for psychometric measures, brain derived neurotrophic factor (BDNF, circadian salivary cortisol levels, and pro- and anti-inflammatory cytokines. Participation in the retreat was found to be associated with decreases in self-reported anxiety and depression as well as increases in mindfulness. As hypothesized, increases in the plasma levels of BDNF and increases in the magnitude of the cortisol awakening response (CAR were also observed. The normalized change in BDNF levels was inversely correlated with BSI-18 anxiety scores at both the pre-retreat (r = 0.40, p < 0.05 and post-retreat (r = 0.52, p < 0.005 such that those with greater anxiety scores tended to exhibit smaller pre- to post-retreat increases in plasma BDNF levels. In line with a hypothesized decrease in inflammatory processes resulting from the yoga and meditation practices, we found that the plasma level of the anti-inflammatory cytokine Interleukin-10 was increased and the pro-inflammatory cytokine Interleukin-12 was reduced after the retreat. Contrary to our initial hypotheses, plasma levels of other pro-inflammatory cytokines, including Interferon Gamma (IFN-γ, Tumor Necrosis Factor (TNF-α, Interleukin-1β (IL-1β, Interleukin-6 (IL-6, and Interleukin-8 (IL-8 were increased after the retreat. Given evidence from previous studies of the positive effects of meditative practices on mental fitness, autonomic homeostasis and inflammatory status, we hypothesize that these findings are related to the meditative practices throughout the retreat; however, some of the observed changes may also be related to other aspects of the retreat such as physical exercise-related components of the yoga practice and diet. We hypothesize that the patterns of change observed here reflect mind-body integration and well-being. The increased BDNF levels

Creating a specialist protein resource network: a meeting report for the protein bioinformatics and community resources retreat

DEFF Research Database (Denmark)

Babbitt, Patricia C.; Bagos, Pantelis G.; Bairoch, Amos

2015-01-01

During 11–12 August 2014, a Protein Bioinformatics and Community Resources Retreat was held at the Wellcome Trust Genome Campus in Hinxton, UK. This meeting brought together the principal investigators of several specialized protein resources (such as CAZy, TCDB and MEROPS) as well as those from...... protein databases from the large Bioinformatics centres (including UniProt and RefSeq). The retreat was divided into five sessions: (1) key challenges, (2) the databases represented, (3) best practices for maintenance and curation, (4) information flow to and from large data centers and (5) communication...

Retreatment of patients with treatment failure of direct-acting antivirals: Focus on hepatitis C virus genotype 1b.

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Kanda, Tatsuo; Nirei, Kazushige; Matsumoto, Naoki; Higuchi, Teruhisa; Nakamura, Hitomi; Yamagami, Hiroaki; Matsuoka, Shunichi; Moriyama, Mitsuhiko

2017-12-14

The recent development of direct-acting antiviral agents (DAAs) against hepatitis C virus (HCV) infection could lead to higher sustained virological response (SVR) rates, with shorter treatment durations and fewer adverse events compared with regimens that include interferon. However, a relatively small proportion of patients cannot achieve SVR in the first treatment, including DAAs with or without peginterferon and/or ribavirin. Although retreatment with a combination of DAAs should be conducted for these patients, it is more difficult to achieve SVR when retreating these patients because of resistance-associated substitutions (RASs) or treatment-emergent substitutions. In Japan, HCV genotype 1b (GT1b) is founded in 70% of HCV-infected individuals. In this minireview, we summarize the retreatment regimens and their SVR rates for HCV GT1b. It is important to avoid drugs that target the regions targeted by initial drugs, but next-generation combinations of DAAs, such as sofosbuvir/velpatasvir/voxilaprevir for 12 wk or glecaprevir/pibrentasvir for 12 wk, are proposed to be potential solution for the HCV GT1b-infected patients with treatment failure, mainly on a basis of targeting distinctive regions. Clinicians should follow the new information and resources for DAAs and select the proper combination of DAAs for the retreatment of HCV GT1b-infected patients with treatment failure.

The paradox of a long grounding during West Antarctic Ice Sheet retreat in Ross Sea.

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Bart, Philip J; Krogmeier, Benjamin J; Bart, Manon P; Tulaczyk, Slawek

2017-04-28

Marine geological data show that the West Antarctic Ice Sheet (WAIS) advanced to the eastern Ross Sea shelf edge during the Last Glacial Maximum (LGM) and eventually retreated ~1000 km to the current grounding-line position on the inner shelf. During the early deglacial, the WAIS deposited a voluminous stack of overlapping grounding zone wedges (GZWs) on the outer shelf of the Whales Deep Basin. The large sediment volume of the GZW cluster suggests that the grounding-line position of the paleo-Bindschadler Ice Stream was relatively stationary for a significant time interval. We used an upper bound estimate of paleo-sediment flux to investigate the lower bound duration over which the ice stream would have deposited sediment to account for the GZW volume. Our calculations show that the cluster represents more than three millennia of ice-stream sedimentation. This long duration grounding was probably facilitated by rapid GZW growth. The subsequent punctuated large-distance (~200 km) grounding-line retreat may have been a highly non-linear ice sheet response to relatively continuous external forcing such as gradual climate warming or sea-level rise. These findings indicate that reliable predictions of future WAIS retreat may require incorporation of realistic calculations of sediment erosion, transport and deposition.

Long-term follow-up with Granulocyte and Monocyte Apheresis re-treatment in patients with chronically active inflammatory bowel disease

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Karlsson Mats

2010-07-01

Full Text Available Abstract Background Patients with IBD and chronic inflammation refractory to conventional therapy often demonstrate higher risk of serious complications. Combinations of immunosuppression and biological treatment as well as surgical intervention are often used in this patient group. Hence, there is need for additional treatment options. In this observational study, focused on re-treatment and long-term results, Granulocyte/Monocyte Adsorption (GMA, Adacolumn® treatment has been investigated to study efficacy, safety and quality of life in IBD-patients with chronic activity. Methods Fifteen patients with ulcerative colitis and 25 patients with Crohn's disease, both groups with chronically active inflammation refractory to conventional medication were included in this observational study. The patients received 5-10 GMA sessions, and the clinical activity was assessed at baseline, after each completed course, and at week 10 and 20 by disease activity index, endoscopy and quality of life evaluation. Relapsed patients were re-treated by GMA in this follow-up study up to 58 months. Results Clinical response was seen in 85% and complete remission in 65% of the patients. Ten patients in the UC-group (66% and 16 patients in the CD-group (64% maintained clinical and endoscopic remission for an average of 14 months. Fourteen patients who relapsed after showing initial remission were re-treated with GMA and 13 (93% went into a second remission. Following further relapses, all of seven patients were successfully re-treated for the third time, all of three patients for the fourth time and one for a fifth time. Conclusions IBD-patients with chronic inflammation despite conventional therapy seem to benefit from GMA. Re-treatment of relapsing remission patients seems to be effective.

Evidence for slow late-glacial ice retreat in the upper Rangitata Valley, South Island, New Zealand

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Shulmeister, J.; Fink, D.; Winkler, S.; Thackray, G. D.; Borsellino, R.; Hemmingsen, M.; Rittenour, T. M.

2018-04-01

A suite of cosmogenic radionuclide ages taken from boulders on lateral and latero-terminal moraines in the Rangitata Valley, eastern South Island, New Zealand demonstrates that relatively thick ice occupied valley reaches inland of the Rangitata Gorge until c. 21 ka. Thereafter ice began to thin, and by c. 17 ka it had retreated 33 km up-valley of the Rangitata Gorge to the Butler-Brabazon Downs, a structurally created basin in the upper Rangitata Valley. Despite its magnitude, this retreat represents a minor ice volume reduction from 21 ka to 17 ka, and numerous lateral moraines preserved suggest a relatively gradual retreat over that 4 ka period. In contrast to records from adjacent valleys, there is no evidence for an ice-collapse at c. 18 ka. We argue that the Rangitata record constitutes a more direct record of glacial response to deglacial climate than other records where glacial dynamics were influenced by proglacial lake development, such as the Rakaia Valley to the North and the major valleys in the Mackenzie Basin to the south-west. Our data supports the concept of a gradual warming during the early deglaciation in the South Island New Zealand.

Prevalence of multidrug resistance among retreatment pulmonary tuberculosis cases in a tertiary care hospital, Hyderabad, India

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Subhakar Kandi

2013-01-01

Full Text Available Background: India is one of the high tuberculosis (TB burden countries in the world. India ranks second in harboring multi drug resistant (MDR-TB cases. About 50,000 of MDR cases are recorded in retreatment pulmonary TB cases. This study was conducted in a tertiary care facility (Government General and Chest Hospital in Hyderabad, India. Objectives: Toassess: Proportion of the TB patients having MDR-TB at the initiation of retreatment regimen; the prevalence of isoniazid (INH resistance in this geographical area. Materials and Methods: An analytical, observational, prospective cohort study of patients attending the out-patient department from December 2010 to March 2011. Results: Sputum samples from 100 patients were subjected to acid fast bacilli (AFB culture and drug sensitivity testing. Of these, 28 (28% were MDR-TB, 42 (42% were non-MDR-TB and 39% being INH resistance. Conclusions: In conclusion, one third of the retreatment pulmonary TB cases attending a tertiary care institute for TB will be MDR-TB at the initiation of treatment and there is a need to include ethambutol in the continuation phase of new TB case treatment in view of high INH resistance.

Seabed Gradient Controlling Onshore Transport Rates of Surf Sand during Beach Retreat by Sea Level Rise

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Lee, Hee Jun; Yi, Hi-Il

2018-03-01

A simple relationship is proposed for the onshore transport rates of surf-zone sand to evaluate the beach retreat caused by sea level rise. It suggests that the preservation potential of surf sand is proportional inversely to the seabed gradient during beach retreat. According to this relationship, the erosional remnants of surf sand would be more readily developed on a gentler shelf collectively as transgressive sand sheets. This finding may explain the previous studies regarding the Korean shelves that proposed that the Holocene transgressive sand sheets (HTSS) occur not in the steep eastern shelf but in the gentle western shelf. In line with such presence/absence of the HTSS are the results from some coastal seismic profiles obtained in the present study. The profiles indicate that sand deposits are restricted within the nearshore in the eastern coast, whereas they are persistently traceable to the offshore HTSS in the western coast. Tide is proven to have a negligible influence on the total duration of surf-zone processes. This study may be useful in predicting the consequences of the beach retreat that takes place worldwide as sea levels rise as a result of global warming.

Pathology informatics fellowship retreats: The use of interactive scenarios and case studies as pathology informatics teaching tools.

Science.gov (United States)

Lee, Roy E; McClintock, David S; Balis, Ulysses J; Baron, Jason M; Becich, Michael J; Beckwith, Bruce A; Brodsky, Victor B; Carter, Alexis B; Dighe, Anand S; Haghighi, Mehrvash; Hipp, Jason D; Henricks, Walter H; Kim, Jiyeon Y; Klepseis, Veronica E; Kuo, Frank C; Lane, William J; Levy, Bruce P; Onozato, Maristela L; Park, Seung L; Sinard, John H; Tuthill, Mark J; Gilbertson, John R

2012-01-01

Last year, our pathology informatics fellowship added informatics-based interactive case studies to its existing educational platform of operational and research rotations, clinical conferences, a common core curriculum with an accompanying didactic course, and national meetings. The structure of the informatics case studies was based on the traditional business school case study format. Three different formats were used, varying in length from short, 15-minute scenarios to more formal multiple hour-long case studies. Case studies were presented over the course of three retreats (Fall 2011, Winter 2012, and Spring 2012) and involved both local and visiting faculty and fellows. Both faculty and fellows found the case studies and the retreats educational, valuable, and enjoyable. From this positive feedback, we plan to incorporate the retreats in future academic years as an educational component of our fellowship program. Interactive case studies appear to be valuable in teaching several aspects of pathology informatics that are difficult to teach in more traditional venues (rotations and didactic class sessions). Case studies have become an important component of our fellowship's educational platform.

The profile and treatment outcomes of sputum smear positive pulmonary tuberculosis re-treatment cases, in a district medical college of West Bengal, India

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Abinash Agarwala

2014-01-01

Full Text Available Background: In a high tuberculosis (TB burden county like India with different regional demography, knowledge about patient profile has a pivotal role in determining and identifying the factors associated with poor treatment outcomes among TB re-treatment cases. Aim: The aim was to describe the demography and clinical characteristics of TB re-treatment cases and to evaluate the factors associated with poor treatment outcomes among those patients. Settings and Design: A prospective longitudinal cohort study was carried out at chest medicine outdoor from February, 2011 to 2014 in a district medical college of West Bengal, India. Materials and Methods: Sputum smear positive re-treatment pulmonary TB patients attending our chest medicine outdoor during the 3 years study period were evaluated for demographic and clinical characteristics on the basis of previous treatment history and records at the beginning of the study. Patients were followed-up during the 8 months treatment period (Category II treatment regimen under Revised National TB Control Program. At the end of the study period, treatment outcomes were analyzed and factors associated with poor treatment outcomes were identified. Statistical Analysis: All variables were described by proportions, and differences between independent groups were compared using the Chi-square test and Fisher′s exact test, as applicable. Results: Among 74 patients, re-treatment was successful in 75.7% of relapse case, 66.7% of loss to follow-up cases and 53.8% of failure cases. Re-treatment failure was higher (38.5% in treatment failure cases compare to relapse cases (10.8% and initial loss to follow-up cases (16.7%. Young age, male, unmarried, employed who work outside appears to be the risk factors for loss to follow-up. Low body mass index, treatment from the private sector, history of alcoholism, radiological cavitory lesion, larger duration of previous treatment, lesser gap from previous treatment has

The role of bank collapse on tidal creek ontogeny: A novel process-based model for bank retreat

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Gong, Zheng; Zhao, Kun; Zhang, Changkuan; Dai, Weiqi; Coco, Giovanni; Zhou, Zeng

2018-06-01

Bank retreat in coastal tidal flats plays a primary role on the planimetric shape of tidal creeks and is commonly driven by both flow-induced bank erosion and gravity-induced bank collapse. However, existing modelling studies largely focus on bank erosion and overlook bank collapse. We build a bank retreat model coupling hydrodynamics, bank erosion and bank collapse. To simulate the process of bank collapse, a stress-deformation model is utilized to calculate the stress variation of bank soil after bank erosion, and the Mohr-Coulomb failure criterion is then applied to evaluate the stability of the tidal creek bank. Results show that the bank failure process can be categorized into three stages, i.e., shear failure at the bank toe (stage I), tensile failure on the bank top (stage II), and sectional cracking from the bank top to the toe (stage III). With only bank erosion, the planimetric shapes of tidal creeks are funneled due to the gradually seaward increasing discharge. In contrast to bank erosion, bank collapse is discontinuous, and the contribution of bank collapse to bank retreat can reach 85%, highlighting that the expansion of tidal creeks can be dominated by bank collapse process. The planimetric shapes of tidal creeks are funneled with a much faster expansion rate when bank collapse is considered. Overall, this study makes a further step toward more physical and realistic simulation of bank retreat in estuarine and coastal settings and the developed bank collapse module can be readily included in other morphodynamic models.

The Comparative Efficacy of Different Files in The Removal of Different Sealers in Simulated Root Canal Retreatment- An In-vitro Study.

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Kanaparthy, Aruna; Kanaparthy, Rosaiah

2016-05-01

Root canal treatment enjoys a high success rate all over the world and has saved billions of teeth from extraction. However, there are instances of failure, the main causes being insufficient cleaning and inadequate obturation. In such cases the most conservative treatment option would be non-surgical retreatment. It requires regaining access to the entire root canal system through removal of the original root canal filling thus permitting further cleaning and re- obturation. Removal of gutta-percha and sealer becomes a critical step to gain access to the root canal system, remove necrotic tissue debris, bacteria and infected dentin. To compare and evaluate the efficacy of manual hand Hedstrom files and two rotary retreatment file systems ProTaper Universal retreatment files and Mtwo(R) (retreatment) files in the removal of root canal filling material during root canal retreatment and the influence of the type of sealers zinc oxide eugenol and AH plus on the presence of remaining debris in the reinstrumented canals in the apical, middle and coronal third. Sixty single rooted human premolar teeth were divided into 3 Groups of 20 teeth each Group I (20 Teeth): prepared using hand K Files, Group II (20 Teeth): prepared using ProTaper rotary system and Group III (20 Teeth): prepared using Mtwo rotary system. In Groups- IA, IIA, IIIA: (10 teeth each) Obturation was done using Zinc Oxide Eugenol sealer and gutta percha. In Groups- IB, IIB, IIIB: (10 teeth each) obturation was done with AH Plus sealer and gutta percha. All the teeth were subjected to retreatment. Groups IA and IB with Hedstrom files, Groups IIA and IIB with ProTaper retreatment files and for Groups IIIA and IIIB with Mtwo retreatment Files. The roots were longitudinally split and were observed under a stereomicroscope for remaining amount of filling material on the canal walls. Statistical analysis was done using One-way ANOVA (Analysis of variance) test and Tukey HSD Test. Mtwo(R) files showed

Knickpoint formation and retreat: stairway to heaven or pathway to declivity

Science.gov (United States)

Rengers, Francis; Tucker, Gregory

2016-04-01

The importance of knickpoints in shaping fluvial systems has been observed in laboratory settings, small experimental plots, and at the landscape scale. By creating a step in a river's longitudinal profile, knickpoints can shield upstream tributaries from a much lower base level, and therefore represent a buffer in the energy transfer of a stream system. Knickpoints are located at a transition point between the potential energy of material stored upstream and the kinetic energy of erosion processes and sediment transport below the knickpoint. We hypothesize that the long-term persistence of a discrete, retreating knickpoint requires a balance between the fluvial erosion of the feature, and sedimentation rates downstream. Here we present the results of a short-term (four year) study of knickpoint morphology in a natural gully system to better constrain the conditions necessary to preserve distinct knickpoints over time. We monitored knickpoint erosion using time-lapse photography, repeat terrestrial lidar, soil moisture monitoring, and rainfall-runoff measurements. Our results indicate that shallow subsurface hydrology leads to knickpoint erosion via mass failure, and produces a stable and predictable morphological signature of knickpoint erosion (amphitheater shaped heads). We generalized these observations into a numerical model of erosion/sedimentation to understand the geomorphic legacy of knickpoints in deeply incised gullies. Modeling showed that knickpoints can maintain an incisional step for hundreds to thousands of years when knickpoints retreat via mass failure and sediment is removed from the knickpoint base by fluvial scour. To test simulations of long-term stability generated by the numerical model, we used Optically Stimulated Luminesence to date alluvial deposits at existing gully knickpoints. This geochronological dating confirmed that gully knickpoints have been active in our study area for hundreds to thousands of years, particularly during drought

[Test your decision-making. When to do endodontic retreatment? Results of a study].

Science.gov (United States)

Aryanpour, S; D'Hoore, W; Van Nieuwenhuysen, J P

2000-01-01

The goals of this survey were to determine the most frequent therapeutic option and to evaluate the consensus among a sample of Belgian practitioners managing the same simulated cases of root treated teeth. On average, conservative options (nonsurgical retreatment 35.27% and no retreatment 29.61%) are the most selected alternatives. Surgical options and extraction respectively constitute 21.18% and 13% of the treatment propositions. As expected, the presence of radiographic and/or clinical signs resulted in a more aggressive attitude, but the presence of symptoms does not seem to be a valid reason for reintervention. The results of the study demonstrate considerable interindividual variations in clinical management of root treated teeth, regardless of personal factors, such as gender, years of experience and graduation institution. Even if a consensus appears within a group of professionals, it is not necessarily applied by a majority of practitioners; this contributes certainly to the explanation of the geographical or institutional variations noted in the medical practices.

Comparative evaluation of cyclic fatigue resistance of D-RaCe and ProTaper retreatment instruments in curved artificial canals.

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Topçuoğlu, H S; Topçuoğlu, G; Aktı, A

2016-06-01

To compare the cyclic fatigue resistance of D-RaCe and ProTaper rotary nickel-titanium (NiTi) retreatment files when used in curved artificial canals. A total of 120 new D-RaCe DR2 and ProTaper D3 retreatment files were tested in stainless steel artificial canals having 45° and 60° angles of curvature. Thirty instruments of each of the file systems were tested in both angles of curvature (n = 30). The retreatment instruments were rotated until fracture to calculate the number of cycles to failure. The length of each fractured fragment was recorded. Data were analysed by independent sample t-test. Fractured surfaces of the instruments were analysed by scanning electron microscopy. In the canal with 45° angle of curvature, no significant difference was observed between the retreatment systems (P > 0.05); on the other hand, in the canal with 60° angle of curvature, D-RaCe DR2 instruments had greater cyclic fatigue resistance than ProTaper D3 (P  0.05). The fracture surfaces of the instruments had morphologic characteristics of ductile fracture. D-RaCe DR2 instrument exhibited greater cyclic fatigue resistance than ProTaper D3 only in root canals with 60° angle of curvature. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Efficacy of Twisted File Adaptive, Reciproc and ProTaper Universal Retreatment instruments for root-canal-filling removal: A cone-beam computed tomography study.

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Akbulut, Makbule Bilge; Akman, Melek; Terlemez, Arslan; Magat, Guldane; Sener, Sevgi; Shetty, Heeresh

2016-01-01

The aim of this study was to evaluate the efficacy of Twisted File (TF) Adaptive, Reciproc, and ProTaper Universal Retreatment (UR) System instruments for removing root-canal-filling. Sixty single rooted teeth were decoronated, instrumented and obturated. Preoperative CBCT scans were taken and the teeth were retreated with TF Adaptive, Reciproc, ProTaper UR, or hand files (n=15). Then, the teeth were rescanned, and the percentage volume of the residual root-canal-filling material was established. The total time for retreatment was recorded, and the data was statistically analyzed. The statistical ranking of the residual filling material volume was as follows: hand file=TF Adaptive>ProTaper UR=Reciproc. The ProTaper UR and Reciproc systems required shorter periods of time for retreatment. Root canal filling was more efficiently removed by using Reciproc and ProTaper UR instruments than TF Adaptive instruments and hand files. The TF Adaptive system was advantageous over hand files with regard to operating time.

Endodontic retreatment of dens invaginatus presenting with gutta-percha overfilling at the attached gingiva and chronic apical periodontitis: unusual clinical report.

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Robazza, Carlos Roberto Colombo; Alves e Motta, Julio Cesar; de Carli, Marina Lara; de Oliveira Pedreira, Fernanda Rafaelly; Hanemann, Joao Adolfo Costa

2013-05-01

This work describes the retreatment of an unusual case of dens invaginatus with gutta-percha overfilling at the gingival mucosa and chronic apical periodontitis in a 34-year-old woman. Initial periapical radiograph showed the presence of type II dens invaginatus with poor quality obturation, root perforation and chronic apical periodontitis of tooth 22. Dens invaginatus is a tooth malformation caused by infolding of the dental papilla during tooth development. This anomaly has been associated with increased prevalence of pulpal and periapical diseases. Conventional endodontic retreatment was performed using rotary files and calcium hydroxide paste as intracanal dressing. After 7 days, root canal was filled with guttapercha points and Sealapex® sealer. Obturation was radiographically followed and, after 3 years, absence of fistula and periapical radiolucency was observed, thus conventional endodontic therapy proved to be successful. Conventional endodontic retreatment of type II dens invaginatus has been successful for a 3-year period, showing a better treatment alternative. Conservative endodontic retreatment of dens invaginatus should be considered to promote periapical healing with complete reconstitution of bone and periodontal ligament regeneration without signs of recurrence over a period of 3 years. Moreover, it preserves the entire tooth.

Retreatment of Recurrent Cystic Craniopharyngioma With Chromic Phosphorus P 32

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Kumar, P.P.; Good, R.R.; Skultety, F.M.; Jones, E.O.; Chu, W.K.

1986-01-01

A cystic craniopharyngioma in a two-year-old boy recurred six months after surgery and postoperative external-beam radiotherapy. Successful retreatment was accomplished with radioisotope injection of 0.5 mCi of chromic phosphorus P 32 into the intracranial cyst, which delivered approximately 300.00 Gy to the cyst wall. The patient's symptoms were relieved, and he is without evidence of disease or cystic fluid accumulation four years after intracavitary 32P irradiation. ImagesFigure 1Figure 2Figure 3 PMID:3735454

Evaluation of Dentin Defect Formation during Retreatment with Hand and Rotary Instruments: A Micro-CT Study.

Science.gov (United States)

Yilmaz, Ayca; Helvacioglu-Yigit, Dilek; Gur, Cansu; Ersev, Handan; Kiziltas Sendur, Gullu; Avcu, Egemen; Baydemir, Canan; Abbott, Paul Vincent

2017-01-01

The purpose of this study was to compare the incidence and longitudinal propagation of dentin defects after gutta-percha removal with hand and rotary instruments using microcomputed tomography. Twenty mandibular incisors were prepared using the balanced-force technique and scanned in a 19.9  μ m resolution. Following filling with the lateral compaction technique, gutta-percha was removed with ProTaper Universal Retreatment (PTUR) or hand instruments. After rescanning, a total of 24,120 cross-sectional images were analyzed. The numbers, types, and longitudinal length changes of defects were recorded. Defects were observed in 36.90% of the cross sections. A total of 73 defects were comprised of 87.67% craze lines, 2.73% partial cracks, and 9.58% fractures. No significant difference in terms of new defect formation was detected between the retreatment groups. The apical and middle portions of the roots had more dentin defects than the coronal portions. Defects in three roots of the PTUR instrument group increased in length. Under the conditions of this in vitro study, gutta-percha removal seemed to not increase the incidence of dentin defect formation, but the longitudinal defect propagation finding suggests possible cumulative dentinal damage due to additional endodontic procedures. Hand and rotary instrumentation techniques caused similar dentin defect formation during root canal retreatment.

Where to “Rock”? Choice of retreat sites by a gecko in a semi-arid habitat

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Andreia Penado

2015-06-01

Full Text Available The Selvagens gecko (Tarentola boettgeri bischoffi Joger, 1984 is a medium sized gecko endemic to the Selvagens archipelago, Madeira, Portugal. The biology of this gecko is poorly known and in this study we present the first evidence regarding its habitat use. In 2010 (spring and autumn and 2011 (spring, we collected data on the characteristics of the habitat surrounding 168 rocks used by these geckos as retreat sites, as well as on 75 randomly selected rocks. We also recorded body measurements of the individuals caught under each rock. In both seasons retreat site occupancy was found to be related to rock area, with geckos being found mainly under large rocks. Interestingly, we found that in spring heavier males, in better body condition, occupied the largest rocks and larger geckos occupied rocks closer to creek beds. Our results shed some light upon the behavioural ecology of this nocturnally active ectotherm, that spends the day under a retreat site: i intraspecific competition may be an ecological factor prevalent in this species, since larger individuals occupy larger rocks, located in a presumably high quality micro-habitat; ii the possibility of spring territoriality in males, that compete for good quality shelters.

Pathology informatics fellowship retreats: The use of interactive scenarios and case studies as pathology informatics teaching tools

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Roy E Lee

2012-01-01

Full Text Available Background: Last year, our pathology informatics fellowship added informatics-based interactive case studies to its existing educational platform of operational and research rotations, clinical conferences, a common core curriculum with an accompanying didactic course, and national meetings. Methods: The structure of the informatics case studies was based on the traditional business school case study format. Three different formats were used, varying in length from short, 15-minute scenarios to more formal multiple hour-long case studies. Case studies were presented over the course of three retreats (Fall 2011, Winter 2012, and Spring 2012 and involved both local and visiting faculty and fellows. Results: Both faculty and fellows found the case studies and the retreats educational, valuable, and enjoyable. From this positive feedback, we plan to incorporate the retreats in future academic years as an educational component of our fellowship program. Conclusions: Interactive case studies appear to be valuable in teaching several aspects of pathology informatics that are difficult to teach in more traditional venues (rotations and didactic class sessions. Case studies have become an important component of our fellowship′s educational platform.

Nonsurgical endodontic retreatment of fused teeth with transposition: a case report

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Miguel Agostinho Beco Pinto Cardoso

2016-05-01

Full Text Available Tooth transposition is a disorder in which a permanent tooth develops and erupts in the normal position of another permanent tooth. Fusion and gemination are developmental disturbances presenting as the union of teeth. This article reports the nonsurgical retreatment of a very rare case of fused teeth with transposition. A patient was referred for endodontic treatment of her maxillary left first molar in the position of the first premolar, which was adjacent to it on the distobuccal side. Orthopantomography and periapical radiography showed two crowns sharing the same root, with a root canal treatment and an associated periapical lesion. Tooth fusion with transposition of a maxillary molar and a premolar was diagnosed. Nonsurgical endodontic retreatment was performed. At four yr follow-up, the tooth was asymptomatic and the radiolucency around the apical region had decreased, showing the success of our intervention. The diagnosis and treatment of fused teeth require special attention. The canal system should be carefully explored to obtain a full understanding of the anatomy, allowing it to be fully cleaned and obturated. Thermoplastic techniques were useful in obtaining hermetic obturation. A correct anatomical evaluation improves the set of treatment options under consideration, leading to a higher likelihood of esthetically and functionally successful treatment.

Predicting the retreat and migration of tidal forests along the northern Gulf of Mexico under sea-level rise

Science.gov (United States)

Doyle, T.W.; Krauss, K.W.; Conner, W.H.; From, A.S.

2010-01-01

Tidal freshwater forests in coastal regions of the southeastern United States are undergoing dieback and retreat from increasing tidal inundation and saltwater intrusion attributed to climate variability and sea-level rise. In many areas, tidal saltwater forests (mangroves) contrastingly are expanding landward in subtropical coastal reaches succeeding freshwater marsh and forest zones. Hydrological characteristics of these low-relief coastal forests in intertidal settings are dictated by the influence of tidal and freshwater forcing. In this paper, we describe the application of the Sea Level Over Proportional Elevation (SLOPE) model to predict coastal forest retreat and migration from projected sea-level rise based on a proxy relationship of saltmarsh/mangrove area and tidal range. The SLOPE model assumes that the sum area of saltmarsh/mangrove habitat along any given coastal reach is determined by the slope of the landform and vertical tide forcing. Model results indicated that saltmarsh and mangrove migration from sea-level rise will vary by county and watershed but greater in western Gulf States than in the eastern Gulf States where millions of hectares of coastal forest will be displaced over the next century with a near meter rise in relative sea level alone. Substantial losses of coastal forests will also occur in the eastern Gulf but mangrove forests in subtropical zones of Florida are expected to replace retreating freshwater forest and affect regional biodiversity. Accelerated global eustacy from climate change will compound the degree of predicted retreat and migration of coastal forests with expected implications for ecosystem management of State and Federal lands in the absence of adaptive coastal management.

Yoga Retreat : Grafiikan työstäminen Facebook peliin

OpenAIRE

Kälviäinen, Jenna

2013-01-01

In the thesis the process of graphic design of Facebook games is discussed. The Author got an opportunity to work as a graphic designer for Gajatri Studios in their first video game project called Yoga Retreat. Experiences from the project, the decisions made and the problems faced were analyzed in detail. In the theory section the history of Facebook in general was explored and the question of how Facebook became one of the most well-known websites of the Internet was discussed as well as...

Retreatment with peg-interferon and ribavirin in patients with chronic hepatitis C virus genotype 2 or 3 infection with prior relapse

DEFF Research Database (Denmark)

Lagging, Martin; Rembeck, Karolina; Rauning Buhl, Mads

2013-01-01

Uncertainty remains regarding the efficacy of retreatment with current standard-of-care peg-interferon (peg-IFN) and ribavirin among patients infected with hepatitis C virus (HCV) genotypes 2 or 3 with relapse after prior therapy.......Uncertainty remains regarding the efficacy of retreatment with current standard-of-care peg-interferon (peg-IFN) and ribavirin among patients infected with hepatitis C virus (HCV) genotypes 2 or 3 with relapse after prior therapy....

Treatment and retreatment with omalizumab in chronic spontaneous urticaria: Real life experience with twenty-five patients

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Murat Türk

2018-01-01

Conclusions: Omalizumab has high efficacy in both the treatment and retreatment of CSU; however, relapse rates after discontinuation are high. Autoimmune markers may be helpful in predicting treatment response and relapse.

Evaluation of image-guided helical tomotherapy for the retreatment of spinal metastasis

International Nuclear Information System (INIS)

Mahan, Stephen L.; Ramsey, Chester R.; Scaperoth, Daniel D.; Chase, Daniel J.; Byrne, Thomas E.

2005-01-01

Introduction: Patients with vertebral metastasis that receive radiation therapy are typically treated to the spinal cord tolerance dose. As such, it is difficult to successfully deliver a second course of radiation therapy for patients with overlapping treatment volumes. In this study, an image-guided helical tomotherapy system was evaluated for the retreatment of previously irradiated vertebral metastasis. Methods and Materials: Helical tomotherapy dose gradients and maximum cord doses were measured in a cylindrical phantom for geometric test cases with separations between the planning target volume (PTV) and the spinal cord organ at risk (OAR) of 2 mm, 4 mm, 6 mm, 8 mm, and 10 mm. Megavoltage computed tomography (CT) images were examined for their ability to localize spinal anatomy for positioning purposes by repeat imaging of the cervical spine in an anthropomorphic phantom. In addition to the phantom studies, 8 patients with cord compressions that had received previous radiation therapy were retreated to a mean dose of 28 Gy using conventional fractionation. Results and Discussion: Megavoltage CT images were capable of positioning an anthropomorphic phantom to within ±1.2 mm (2σ) superior-inferiorly and within ±0.6 mm (2σ) anterior-posteriorly and laterally. Dose gradients of 10% per mm were measured in phantom while PTV uniformity indices of less than 11% were maintained. The calculated maximum cord dose was 25% of the prescribed dose for a 10-mm PTV-to-OAR separation and 71% of the prescribed dose for a PTV-to-OAR separation of 2 mm. Eight patients total have been treated without radiation-induced myelopathy or any other adverse effects from treatment. Conclusions: A technique has been evaluated for the retreatment of vertebral metastasis using image-guided helical tomotherapy. Phantom and patient studies indicated that a tomotherapy system is capable of delivering dose gradients of 10% per mm and positioning the patient within 1.2 mm without the use of

Evaluation of Dentin Defect Formation during Retreatment with Hand and Rotary Instruments: A Micro-CT Study

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Ayca Yilmaz

2017-01-01

Full Text Available The purpose of this study was to compare the incidence and longitudinal propagation of dentin defects after gutta-percha removal with hand and rotary instruments using microcomputed tomography. Twenty mandibular incisors were prepared using the balanced-force technique and scanned in a 19.9 μm resolution. Following filling with the lateral compaction technique, gutta-percha was removed with ProTaper Universal Retreatment (PTUR or hand instruments. After rescanning, a total of 24,120 cross-sectional images were analyzed. The numbers, types, and longitudinal length changes of defects were recorded. Defects were observed in 36.90% of the cross sections. A total of 73 defects were comprised of 87.67% craze lines, 2.73% partial cracks, and 9.58% fractures. No significant difference in terms of new defect formation was detected between the retreatment groups. The apical and middle portions of the roots had more dentin defects than the coronal portions. Defects in three roots of the PTUR instrument group increased in length. Under the conditions of this in vitro study, gutta-percha removal seemed to not increase the incidence of dentin defect formation, but the longitudinal defect propagation finding suggests possible cumulative dentinal damage due to additional endodontic procedures. Hand and rotary instrumentation techniques caused similar dentin defect formation during root canal retreatment.

Application of safety checklist to the analysis of the IEA-R1 reactor water retreatment system

International Nuclear Information System (INIS)

Sauer, Maria Eugenia Lago Jacques; Sara Neto, Antonio Jorge; Lima, Toni Carlos Caboclo de; Ribeiro, Maria Alice Morato

2005-01-01

In 1999, the management of the IEA-R1 Research Reactor (pool type - 5 MWth), located at IPEN/CNEN-SP, started the evaluation of the Reactor Pool Water Retreatment System to identify operational aspects, which could compromise the operators safety. The purpose was to identify and propose enhancements to the system which would be installed to substitute for the existing one. This process was conducted through a qualitative study of the system in operation. This study was carried out by a team composed of specialists in reactor operation, systems maintenance and radiological protection, and one safety analyst. The study consisted, basically, in local inspections to verify the physical and operational conditions of each equipment / component as well as aspects related to maintenance activities of the system. The process control and the operator procedures associated with the retreatment of the reactor pool water were also reviewed. The methodology adopted to develop the study was based in process hazard analysis technique named Safety Checklist. This paper presents a summary of this study and the main results obtained. Some operational and safety problems identified, the prevention and/or correction means to avoid them, and the recommendations and suggestions that have been implemented to the new design of the IEA-R1 Reactor Water Retreatment System, whose installation was concluded in 2003, are also presented. (author)

Factors contributing to the surgical retreatment of mandibular fractures

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João Gualberto de Cerqueira Luz

2013-06-01

Full Text Available The purpose of this retrospective study was to evaluate contributing factors in patients requiring surgical retreatment of mandibular fractures. Of all the patients with mandibular fractures who were treated using internal fixation at a trauma hospital over a seven-year period, 20 patients (4.7% required a second surgery and thus composed the “reoperated” group. The control group comprised 42 consecutive patients with mandibular fractures who were treated at the same clinic and who healed without complications. Medical charts were reviewed for gender, age, substance abuse history, dental condition, etiology, location of fracture, degree of fragmentation, fracture exposure, teeth in the fracture line, associated facial fractures, polytrauma, time elapsed between trauma and initial treatment, surgical approach and fixation system. Statistical analyses were performed using the Statistical Package for Social Sciences (SPSS version 20.0; descriptive statistics and the chi-squared test were used to determine differences between groups. Significant differences in substance abuse (p = 0.006, dental condition (p < 0.001, location of fracture (p = 0.010, degree of fragmentation (p = 0.003 and fracture exposure (p < 0.001 were found. With regard to age and time elapsed between trauma and initial treatment, older patients (31.4 years, SD = 11.1 and a delay in fracture repair (19.1 days, SD = 18.7 were more likely to be associated with reoperation. It was concluded that substance abuse, age, dental condition, location of fracture, degree of fragmentation, fracture exposure and the time between trauma and initial treatment should be considered contributing factors to the occurrence of complications that require surgical retreatment of mandibular fractures.

Linking Tarim Basin sea retreat (west China) and Asian aridification in the late Eocene

NARCIS (Netherlands)

Bosboom, R.; Dupont-Nivet, G.; Grothe, A.; Brinkhuis, H.; Villa, G.; Mandic, O.; Stoica, M.; Huang, W.; Yang, W.; Guo, Z.; Krijgsman, W.

2014-01-01

The Tarim Basin in western China formed the easternmost margin of a shallow epicontinental sea that extended across Eurasia and was well connected to the western Tethys during the Paleogene. Climate modelling studies suggest that the westward retreat of this sea from Central Asia may have been as

Efficacy of Different Nickel-Titanium Instruments in Removing Gutta-percha during Root Canal Retreatment.

Science.gov (United States)

Özyürek, Taha; Demiryürek, Ebru Özsezer

2016-04-01

The aim of this study was to compare the cleanliness of root canal walls after retreatment using ProTaper Next (PTN; Dentsply Maillefer, Ballaigues, Switzerland), Twisted File Adaptive (TFA; Axis/SybronEndo, Orange, CA), Reciproc (PRC; VDW, Munich, Germany), and ProTaper Universal retreatment (PTR, Dentsply Maillefer) nickel-titanium systems and the time required for gutta-percha and sealer removal. Eighty human maxillary central incisors with single and straight root canals were instrumented up to #40.02 with manual K-files (Dentsply Maillefer) and obturated using the continuous wave of condensation technique. Removal of the gutta-percha and sealer was performed using 1 of the following nickel-titanium systems: PTN, TFA, RPC, or PTR. The teeth were sectioned, and digital images were captured. The photographs were analyzed using AutoCAD software (Autodesk, San Rafael, CA). Also, the total time required for gutta-percha removal was calculated by a chronometer. The total retreatment time was significantly shorter in the PTR group compared with the other groups (P < .05). There was a significant difference between the groups according to the total residual gutta-percha and sealer (P < .05). The PTN and PTR groups left significantly less gutta-percha and sealer remnant than the TFA and RPC groups (P < .05). Within the limitations of this study, the PTN and the PTR groups showed less residual gutta-percha and sealer than the TFA and RPC groups. The time required for gutta-percha and sealer removal was similar for all the groups, except for the PTR group. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Call for papers: SAJHE special issue 'Re-imagining writing retreats for academic staff in higher education'

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Guest Editors

2016-06-01

Full Text Available Call for papers for an upcoming special issue of the South African Journal of Higher Education (SAJHE in 2016: ‘Re-imagining writing retreats for academic staff in higher education’.

LASIK and PRK in hyperopic astigmatic eyes: is early retreatment advisable?

Science.gov (United States)

Frings, Andreas; Richard, Gisbert; Steinberg, Johannes; Druchkiv, Vasyl; Linke, Stephan Johannes; Katz, Toam

2016-01-01

To analyze the refractive and keratometric stability in hyperopic astigmatic laser in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) during the first 6 months after surgery. This retrospective cross-sectional study included 97 hyperopic eyes; 55 were treated with LASIK and 42 with PRK. Excimer ablation for all eyes was performed using the ALLEGRETTO excimer laser platform using a mitomycin C for PRK and a mechanical microkeratome for LASIK. Keratometric and refractive data were analyzed during three consecutive follow-up intervals (6 weeks, 3 months, and 6 months). The corneal topography was obtained using Scheimpflug topography, and subjective refractions were acquired by expert optometrists according to a standardized protocol. After 3 months, mean keratometry and spherical equivalent were stable after LASIK, whereas PRK-treated eyes presented statistically significant (P1 D occurred. The optical zone diameter did not correlate with the development of regression. After corneal laser refractive surgery, keratometric changes are followed by refractive changes and they occur up to 6 months after LASIK and for at least 6 months after PRK, and therefore, caution should be applied when retreatment is planned during the 1st year after surgery because hyperopic refractive regression can lead to suboptimal visual outcome. Keratometric and refractive stability is earlier achieved after LASIK, and therefore, retreatment may be independent of late regression.

The St. Ignatius Jesuit Retreat and Training Centre: Cultivating Ecological Awareness and Connection with the Earth

Science.gov (United States)

Groen, Janet

2017-01-01

This chapter focuses on the role of religiously based spirituality in cultivating environmental awareness and citizenship by examining an adult environmental education program offered at the Ignatius Jesuit Centre, a religious retreat center in Guelph, Canada.

Comparison of debris extruded apically and working time used by ProTaper Universal rotary and ProTaper retreatment system during gutta-percha removal

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Mary Kinue Nakamune Uezu

2010-12-01

Full Text Available OBJECTIVE: The aim of this study was to evaluate the in vitro action of ProTaper retreatment files and ProTaper Universal in the retreatment of mandibular premolars. MATERIAL AND METHODS: The amount of debris extruded apically was measured and the time to reach the working length and to complete the removal of gutta-percha was observed. Thirty teeth had their canals prepared using ProTaper Universal files and were obturated by the single cone technique. The teeth were then stored at 37ºC in a humid environment for 7 days. During the use of the rotary instruments for root canal filling removal, the apical portions of the teeth were attached to the open end of a resin tube to collect the apically extruded debris. RESULTS: ProTaper Universal files were significantly faster (p=0.0011 than the ProTaper retreatment files to perform gutta-percha removal, but no significant difference was found between the files regarding the time to reach the working length or the amount of apical extrusion. CONCLUSIONS: ProTaper Universal rotary had better results for endodontic retreatment, and both techniques promote similar apical extrusion of debris.

Interference of partial visual analysis of root filling quality and apical status on retreatment decisions

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Renata Dornelles Morgental

2012-04-01

Full Text Available OBJECTIVE: The presence of periapical radiolucency has been used as a criterion for endodontic treatment failure. However, in addition to the inherent limitations of radiographic examinations, radiographic interpretations are extremely subjective. Thus, this study investigated the effect of partial analysis of root filling quality and periapical status on retreatment decisions by general dentists. MATERIAL AND METHODS: Twelve digitalized periapical radiographs were analyzed by 10 observers. The study was conducted at three time points at 1-week intervals. Radiographs edited with the Adobe Photoshop CS4 software were analyzed at three time points: first, only root filling quality was analyzed; second, only the periapical areas of the teeth under study were visualized; finally, observers analyzed the unedited radiographic image. Spearman ’s coefficient was used to analyze the correlations between the scores assigned when the periapical area was not visible and when the unedited radiograph was analyzed, as well as between the scores assigned when root fillings where not visible and when the unedited radiograph was analyzed. Sensitivity, specificity, positive and negative predictive values between partial images and unedited radiographs were also used to analyze retreatment decisions. The level of significance was set at 5%. RESULTS: The visualization of the root filling on the unedited radiograph affected the interpretation of the periapical status and the technical quality of the fillings has a greater influence on the general dentist’s decision to prescribe endodontic retreatment than the periapical condition. CONCLUSION: In order to make endodontic diagnosis, radiographic interpretation process should not only emphasize technical aspects, but also consider biological factors.

Dry-season retreat and dietary shift of the dart-poison frog Dendrobates tinctorius (Anura: Dendrobatidae)

NARCIS (Netherlands)

Born, M.; Bongers, F.; Poelman, E.H.; Sterck, F.J.

2010-01-01

Dry-season retreat and dietary shift of the dart-poison frog Delldrobates tillCtOrillS (Anura: Dendrobatidae). Seasonal rainfall affects tropical forest dynamics and behavior of species that are part of these ecosystems. TIle positive correlation between amphibian ac tivity pattems and rainfall has

Got Dating: Outcomes of a Teen 4-H Relationship Retreat

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Naomi Brower

2012-03-01

Full Text Available To support youth in developing healthy relationships, state and county staff collaborated to offer a statewide overnight teen retreat to teach health relationship skills. Evaluation of 64 youth participants from rural and urban counties found significant increases in posttest knowledge of relationship skills for both male and female youth. Youth also reported that the content was very helpful and worth repeating. Program success may be attributed to addressing the interesting and needed subject of dating relationships as well as involvement of state ambassador and collegiate 4-H members as teachers. Implications and replication suggestions are outlined.

Late Eocene sea retreat from the Tarim Basin (west China) and concomitant Asian paleoenvironmental change

NARCIS (Netherlands)

Bosboom, R.E.; Dupont-Nivet, G.; Houben, A.J.P.; Brinkhuis, H.; Villa, G.; Mandic, O.; Stoica, M.; Zachariasse, W.J.; Guo, ZJ.; Li, CX.; Krijgsman, W.

2011-01-01

The Paleogene sediments of the southwest Tarim Basin along the West Kunlun Shan in western China include the remnants of the easternmost extent of a large epicontinental sea. This shallow sea once extended across the Eurasian continent before it retreated westward and eventually separated as the

Qualidade visual após retratamento de LASIK personalizado versus convencional Visual quality after custom versus standard LASIK retreatment

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Andréia Peltier Urbano

2008-12-01

Full Text Available OBJETIVO: Avaliar a qualidade visual após retratamento personalizado e retratamento convencional em olhos submetidos a LASIK primário convencional. MÉTODOS: Foi realizado estudo prospectivo de 74 olhos submetidos ao retratamento de LASIK para correção de miopia e astigmatismo. Cada paciente foi submetido ao retratamento de LASIK com ablação personalizada (Zyoptix, Bausch & Lomb em um olho e ablação convencional (Planoscan, Bausch & Lomb no olho contralateral. Foram comparados os resultados do teste de ofuscamento e da sensibilidade ao contraste durante o acompanhamento de seis meses. RESULTADOS: Os olhos do grupo Zyoptix apresentaram melhores resultados no teste de ofuscamento e na sensibilidade ao contraste do que o olho contralateral, quando se compararam os resultados. CONCLUSÕES: O retratamento personalizado resultou em melhor qualidade visual pós-operatória do que o retratamento convencional de LASIK primário convencional.PURPOSE: To evaluate visual quality after wavefront-guided LASIK versus standard LASIK in retreatment of primary LASIK for myopia and myopic astigmatism. METHODS: A prospective study was performed with paired eye control of 74 eyes with LASIK retreatment. Each patient underwent retreatment using custom ablation (Zyoptix, Bausch & Lomb in 1 eye and standard ablation LASIK (PlanoScan, Bausch & Lomb in the contralateral eye. A complete ophthalmologic examination was performed, including evaluation of glare test and contrast sensitivity test, with a follow-up of 6 months. RESULTS: Zyoptix eyes showed better results of glare test and contrast sensitivity test than the contralateral eyes. CONCLUSIONS: Wavefront-guided LASIK produces better visual quality than standard LASIK in the retreatment of refractive errors after primary LASIK.

Impact of glaciers retreat on highland Andean wetlands and communities: lessons from the upper Cachi catchment (Ayacucho, Peru)

Science.gov (United States)

Angulo, Oscar; Biévre Bert, De

2017-04-01

The vulnerability of water resources under climate change scenarios in Peru is generally regarded to be connected to a diminished availability of water due to retreating glaciers. However, the impact of glacier retreat goes much beyond a decline of glacial water reserves. This article argues that another important impact is the extreme erosion in areas where glaciers have recently melted, as well as the accumulation of erosion material in highland wetlands located downslope. As a direct consequence of these changes highland Andean communities which depend on these ecosystems are affected in socio-economic terms as they find themselves forced to alter ancestral dynamics and traditional practices of land and water use. This quickly leads to a vicious cycle of risks and threats. In such a context a possibility to adapt to glacial retreat should be to protect areas affected by glacial melt in order to enable a rapid development of protective vegetation cover. In the upper catchment of the Cachi River interesting experiences of protection and water harvesting exist that could be extended to other high vulnerability areas for the benefit of highland populations as well as downstream water users, such as the irrigation system of Cachi and the city of Ayacucho.

Orthodontic-surgical retreatment of facial asymmetry with occlusal cant and severe root resorption: A 3-year follow-up.

Science.gov (United States)

Lisboa, Cinthia de Oliveira; Borges, Marlon Sampaio; Medeiros, Paulo José D'Albuquerque; Motta, Alexandre Trindade; Mucha, José Nelson

2017-08-01

Our objective was to report the orthodontic and surgical retreatment of a patient who had undergone a prolonged orthodontic treatment with extractions, but who had unsatisfactory results and persistent side effects. The man, aged 25 years 3 months, sought treatment with major complaints of facial and smile asymmetries. The clinical examination showed a mandibular deviation to the right and a maxillary occlusal cant. A Class II Division 1 subdivision right was observed. Radiographic examination showed extensive root resorptions in the maxillary second premolars and absence of the 4 first premolars. The maxillary midline was deflected 2 mm to the left, and the mandibular midline was shifted 5 mm to the right. Aligning and leveling were performed with orthodontic fixed appliances, with a standard edgewise system (0.022 × 0.028 in), followed by LeFort I maxillary impaction and bilateral sagittal split osteotomy with asymmetrical advancement. Retreatment showed outstanding results that remained stable after 3 years of follow-up. Root resorption in the second premolars did not seem to increase. Orthodontic-surgical intervention is the main choice for correcting esthetic and functional problems in facial asymmetry, particularly in cases of retreatment. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Retreatment with bevacizumab in patients with gynecologic malignancy is associated with clinical response and does not increase morbidity

Directory of Open Access Journals (Sweden)

Laskey RA

2014-03-01

Full Text Available Robin A Laskey,1 Scott D Richard,2 Ashlee L Smith,1 Jeff F Lin,1 Tiffany L Beck,3 Jamie L Lesnock,1 Joseph L Kelley 3rd,1 Alexander B Olawaiye,1 Paniti Sukumvanich,1 Thomas C Krivak4 1Division of Gynecologic Oncology, Magee-Womens Hospital of UPMC, Pittsburgh, 2Division of Gynecologic Oncology, Drexel University College of Medicine/Hahnemann University Hospital, Philadelphia, 3Department of Obstetrics, Gynecology and Reproductive Sciences, Magee-Womens Hospital of UPMC, Pittsburgh, 4Division of Gynecologic Oncology, Western Pennsylvania Hospital, Pittsburgh, PA, USA Purpose: Bevacizumab (Bev is associated with improved progression-free survival in advanced epithelial ovarian cancer. The use of Bev in patients with gynecologic malignancy is increasing; however, little is known about cumulative toxicity and response in patients retreated with Bev. Our goal was to determine cumulative side effects and response in patients retreated with Bev. Patients and methods: Women with recurrent gynecologic malignancy treated with Bev between January 2007 and March 2012 at a single institution were identified, including a subset who received Bev in a subsequent regimen. The primary outcome was Bev-associated toxicity, and the secondary outcome was response. Results: Of 83 patients that received Bev for recurrent disease, 23 were retreated with Bev and four received Bev maintenance. Three patients (13% developed grade 3 or 4 hypertension; all had a history of chronic hypertension. One (4.3% patient developed grade 3 proteinuria, and one (4.3% developed an enterovaginal fistula. Four patients discontinued Bev secondary to toxicity. Toxicity was not related to the cumulative number of cycles. Twenty-six percent of patients responded to Bev retreatment. On univariate analysis, there was a significant (P=0.003 overall survival advantage when the Bev-free interval was >9 months (95% confidence interval [CI] 4.9–43.7 compared to ≤9 months (95% CI 2.1–11.5, 24

The potential for retreating alpine glaciers to alter alpine ecosystems in the Colorado Front Range

Science.gov (United States)

Hall, E.; Baron, J.

2013-12-01

Glaciers are retreating at an unprecedented rate. In mid-latitude alpine ecosystems the presence of glaciers and rock glaciers govern rates and ecology of alpine and sub-alpine ecosystems. Changes in the thermal environment due to the loss of isothermal habitat and inputs from glacier melt chemistry are altering alpine ecosystems in unpredictable ways. In particular, glacier may be a source of nitrogen that is altering alpine ecosystem dynamics. Loch Vale Watershed (LVWS) located within Rocky Mountain National Park. LVWS contains a surface glacier (Andrew's glacier) and a rock glacier (Taylor's glacier) at the headwater of each of the two drainages within the watershed. We collected precipitation from a National Atmospheric Deposition Site and surface water from multiple alpine lakes and streams during a particularly high and low snow year in the Colorado Front Range. We also sampled stream and lake sediments at each site to analyze the associated microbial community. Concentrations of nitrate and ammonium, relative abundance of amoA (the gene responsible for a key step in the microbial nitrification pathway), and the dual isotope signal to nitrate all point to snow melt as a key deliverer of nitrogen to ecosystems along the Colorado Front Range. However, late summer surface water chemistry is isotopically similar to the chemistry of glacial ice. This suggests that retreating glacier may be an additional source of N to alpine ecosystems and have the potential to alter microbial community composition, biogeochemical rate processes, and ecosystem function. These dynamics are most likely not unique to the Colorado Front Range and should be globally distributed as glaciers continue to retreat in high altitude ecosystems around the world.

Contributions of culture and antimicrobial susceptibility tests to the retreatment of patients with pulmonary tuberculosis

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Bruno Horta Andrade

2013-08-01

Full Text Available Introduction This study evaluated the efficacy of retreatment of pulmonary tuberculosis (TB with regard to treatment outcomes and antimicrobial susceptibility testing (ST profiles. Methods This retrospective cohort study analyzed 144 patients treated at a referral hospital in Brazil. All of them had undergone prior treatment, were smear-positive for TB and received a standardized retreatment regimen. Fisher's 2-tailed exact test and the χ2 test were used; RRs and 95% CIs were calculated using univariate and multivariate binary logistic regression. Results The patients were cured in 84 (58.3% cases. Failure was associated with relapsed treatment and abandonment (n=34. Culture tests were obtained for 103 (71.5% cases; 70 (48.6% had positive results. ST results were available for 67 (46.5% cases; the prevalence of acquired resistance was 53.7%. There were no significant differences between those who achieved or not therapeutic success (p=0.988, despite being sensitive or resistant to 1 or more drugs. Rifampicin resistance was independently associated with therapeutic failure (OR: 4.4, 95% CI:1.12-17.37, p=0.034. For those cases in which cultures were unavailable, a 2nd model without this information was built. In this, return after abandonment was significantly associated with retreatment failure (OR: 3.59, 95% CI:1.17-11.06, p=0.026. Conclusions In this cohort, the general resistance profile appeared to have no influence on treatment outcome, except in cases of rifampicin resistance. The form of reentry was another independent predictor of failure. The use of bacterial culture identification and ST in TB management must be re-evaluated. The recommendations for different susceptibility profiles must also be improved.

Effectiveness of ProTaper Universal retreatment instruments used with rotary or reciprocating adaptive motion in the removal of root canal filling material.

Science.gov (United States)

Capar, I D; Arslan, H; Ertas, H; Gök, T; Saygılı, G

2015-01-01

To compare the effectiveness of ProTaper Universal retreatment instruments with continuous rotation and adaptive motion (AM; a modified reciprocating motion that combines rotational and reciprocating motion) in the removal of filling material. Mesiobuccal root canals in 36 mandibular first molars were instrumented up to size F2 with the ProTaper Universal instrument (Dentsply Maillefer, Ballaigues, Switzerland) and filled using sealer and ProTaper Universal F2 gutta-percha cones. Gutta-percha was then down-packed and the root canal backfilled using the extruder hand-piece of the Elements Obturation System (SybronEndo, Orange, CA, USA). The teeth were assigned to two groups (n = 18), and removal of the root fillings was performed using one of the following techniques: group 1) ProTaper Universal retreatment files used with rotational motion (RM) and group 2) ProTaper Universal retreatment files used with adaptive motion (AM) (600° clockwise/0° counter-clockwise to 370° clockwise/50° counter-clockwise). The teeth were sectioned, and both halves were analysed at 8 × magnification. The percentage of remaining filling material was recorded. The data were analysed statistically using the Student's t-test at a 95% confidence level (P ProTaper Universal retreatment files with adaptive motion removed more filling materials from root canals than the rotational movement. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Differences in the clinical-epidemiological profile between new cases of tuberculosis and retreatment cases after default.

Science.gov (United States)

Belchior, Aylana de Souza; Arcêncio, Ricardo Alexandre; Mainbourg, Evelyne Marie Therese

2016-01-01

To identify the socioeconomic and clinical-epidemiological factors related to tuberculosis in new cases and retreatment cases. Comparative study with 126 patients, of which 42 were retreatment cases after default attended in a reference center, and 84 were new cases completing the first treatment and treated in Basic Health Units. The collection of primary data was through interview, and of secondary data by records of the Notifiable Diseases Information System. Comparative analysis between the two groups. The new cases differ from retreatment cases regarding educational level. The clinical-epidemiological profile shows a significant difference in relation to performance of the tuberculin skin test, and the HIV test result (positive) in favor of new cases. In relation to performance of sputum culture and the result (positive) of the first sputum smear of the first and second samples, in favor of retreatment cases. The two groups are significantly different in clinical and epidemiological characteristics that show the access to exams. Identificar fatores socioeconômicos e clínico-epidemiológicos associados à tuberculose em casos novos e em casos em retratamento. Estudo comparativo de 126 pacientes, sendo 42 casos em retratamento por abandono atendidos num Centro de Referência e 84 casos novos concluindo o primeiro tratamento, atendidos em Unidades Básicas de Saúde. Levantamento de dados primários por entrevista e dados secundários pela Ficha de Informação de Agravos de Notificação. Análise comparativa entre os dois grupos. Os casos novos diferem dos em retratamento quanto à escolaridade. O perfil clínico-epidemiológico mostra que há diferença significativa quanto à realização do teste tuberculínico e o resultado do teste HIV (positivo) a favor dos casos novos. Quanto à realização da cultura de escarro e o resultado (positivo) da baciloscopia de escarro da primeira e da segunda amostras, a favor dos casos em retratamento. Os dois grupos

Management of curved root canals in endodontics: clinical case of retreatment

International Nuclear Information System (INIS)

Meneses Guzman, Jose Pablo

2005-01-01

The management of curved root canals in endodontics therapy has required time, patience and skill of the operator, and lots collaboration by the patient. Proper cleaning, disinfection, conformation and root canal filling, in most cases, has prevented the appearance of lesions of bacterial origin to apical or maintenance of these lesions in teeth that are portrayed level. A clinical case is described of retreatment of a first mandibular molar by conventional endodontic treatment with their respective steps, to achieve signs of tissue repair at the apical level. (author) [es

River piracy and drainage basin reorganization led by climate-driven glacier retreat

Science.gov (United States)

Shugar, Daniel H.; Clague, John J.; Best, James L.; Schoof, Christian; Willis, Michael J.; Copland, Luke; Roe, Gerard H.

2017-04-01

River piracy--the diversion of the headwaters of one stream into another one--can dramatically change the routing of water and sediment, with a profound effect on landscape evolution. Stream piracy has been investigated in glacial environments, but so far it has mainly been studied over Quaternary or longer timescales. Here we document how retreat of Kaskawulsh Glacier--one of Canada's largest glaciers--abruptly and radically altered the regional drainage pattern in spring 2016. We use a combination of hydrological measurements and drone-generated digital elevation models to show that in late May 2016, meltwater from the glacier was re-routed from discharge in a northward direction into the Bering Sea, to southward into the Pacific Ocean. Based on satellite image analysis and a signal-to-noise ratio as a metric of glacier retreat, we conclude that this instance of river piracy was due to post-industrial climate change. Rapid regional drainage reorganizations of this type can have profound downstream impacts on ecosystems, sediment and carbon budgets, and downstream communities that rely on a stable and sustained discharge. We suggest that the planforms of Slims and Kaskawulsh rivers will adjust in response to altered flows, and the future Kaskawulsh watershed will extend into the now-abandoned headwaters of Slims River and eventually capture the Kluane Lake drainage.

Cost-effectiveness of retreatment with varenicline after failure with or relapse after initial treatment for smoking cessation

Directory of Open Access Journals (Sweden)

Lieven Annemans

2015-01-01

Conclusion: This analysis suggests that in the long term, varenicline retreatment is a dominant intervention, meaning both greater health gains and greater costs saved, over other possible interventions and therefore should be considered as a standard option.

The solutions to your problems in endodontic retreatment and microsurgery

Directory of Open Access Journals (Sweden)

Leslie Ang

2016-06-01

How to find the 4th canal in the upper Second molars in 60% of your patients, How to find the 4th canal in the upper First molars in 90% of your patients, How to retreat canals root filled with metal posts, fiber posts, gutta percha, hard canal cement & thermafils, How to remove fractured posts and posts cemented with resin cements. Understand why and how to perform Endodontic Surgery: How to treat large periapical lesions microsurgically, How to use the latest Ultrasonic technology under the Surgical Operating Microscope in all forms of microsurgery, Learn about the modern concepts in transplants, apicoectomies and intentional replantations.

Correção das aberrações oculares nos retratamentos de LASIK personalizado e convencional Correction of ocular aberrations in custom and standard LASIK retreatments

Directory of Open Access Journals (Sweden)

Andréia Peltier Urbano

2009-10-01

Full Text Available OBJETIVO: Comparar a correção das aberrações oculares nos retratamentos de LASIK personalizado e convencional. MÉTODOS: Foi realizado um estudo prospectivo, randomizado, de 74 olhos de 37 pacientes submetidos ao retratamento de LASIK para correção de miopia e astigmatismo. Cada paciente foi submetido ao retratamento de LASIK personalizado Zyoptix (Bausch & Lomb em um olho e convencional Planoscan (Bausch & Lomb no olho contralateral. Foi comparada a correção das aberrações oculares nos retratamentos personalizado e convencional. RESULTADOS: No sexto mês pós-operatório, os olhos submetidos ao retratamento Zyoptix apresentaram diminuição estatisticamente significativa do defocus, astigmatismo, coma, aberração esférica, segunda ordem, terceira ordem, alta ordem e aberrações totais. Os olhos submetidos ao retratamento Planoscan apresentaram diminuição estatisticamente significativa do defocus, segunda ordem e aberrações totais. CONCLUSÕES: O retratamento personalizado foi superior ao retratamento convencional para a correção das aberrações oculares de baixa e alta ordens.PURPOSE: To compare the correction of ocular aberrations between custom and standard LASIK retreatment. METHODS: Prospective, randomized trial with paired eye control of 74 eyes from 37 patients who underwent LASIK retreatment. Each patient underwent retreatment using Zyoptix LASIK (Bausch & Lomb in 1 eye and Planoscan LASIK (Bausch & Lomb in the fellow eye. Correction of ocular aberrations was compared between custom and standard LASIK retreatments. RESULTS: At 6 months, there was a statistically significant reduction in defocus, astigmatism, coma, spherical aberration, second, third, higher-order and total aberration in Zyoptix eyes. There was a statistically significant reduction in defocus, second-order and total aberration in Planoscan eyes. CONCLUSIONS: Custom retreatment was statistically superior than standard retreatment for correction of lower

Influence of the Gulf Stream on the Barents Sea ice retreat and Eurasian coldness during early winter

International Nuclear Information System (INIS)

Sato, Kazutoshi; Inoue, Jun; Watanabe, Masahiro

2014-01-01

Abnormal sea-ice retreat over the Barents Sea during early winter has been considered a leading driver of recent midlatitude severe winters over Eurasia. However, causal relationships between such retreat and the atmospheric circulation anomalies remains uncertain. Using a reanalysis dataset, we found that poleward shift of a sea surface temperature front over the Gulf Stream likely induces warm southerly advection and consequent sea-ice decline over the Barents Sea sector, and a cold anomaly over Eurasia via planetary waves triggered over the Gulf Stream region. The above mechanism is supported by the steady atmospheric response to the diabatic heating anomalies over the Gulf Stream region obtained with a linear baroclinic model. The remote atmospheric response from the Gulf Stream would be amplified over the Barents Sea region via interacting with sea-ice anomaly, promoting the warm Arctic and cold Eurasian pattern. (letter)

Creating a specialist protein resource network: a meeting report for the protein bioinformatics and community resources retreat.

Science.gov (United States)

Babbitt, Patricia C; Bagos, Pantelis G; Bairoch, Amos; Bateman, Alex; Chatonnet, Arnaud; Chen, Mark Jinan; Craik, David J; Finn, Robert D; Gloriam, David; Haft, Daniel H; Henrissat, Bernard; Holliday, Gemma L; Isberg, Vignir; Kaas, Quentin; Landsman, David; Lenfant, Nicolas; Manning, Gerard; Nagano, Nozomi; Srinivasan, Narayanaswamy; O'Donovan, Claire; Pruitt, Kim D; Sowdhamini, Ramanathan; Rawlings, Neil D; Saier, Milton H; Sharman, Joanna L; Spedding, Michael; Tsirigos, Konstantinos D; Vastermark, Ake; Vriend, Gerrit

2015-01-01

During 11-12 August 2014, a Protein Bioinformatics and Community Resources Retreat was held at the Wellcome Trust Genome Campus in Hinxton, UK. This meeting brought together the principal investigators of several specialized protein resources (such as CAZy, TCDB and MEROPS) as well as those from protein databases from the large Bioinformatics centres (including UniProt and RefSeq). The retreat was divided into five sessions: (1) key challenges, (2) the databases represented, (3) best practices for maintenance and curation, (4) information flow to and from large data centers and (5) communication and funding. An important outcome of this meeting was the creation of a Specialist Protein Resource Network that we believe will improve coordination of the activities of its member resources. We invite further protein database resources to join the network and continue the dialogue.

Preemption versus Entrenchment: Towards a Construction-General Solution to the Problem of the Retreat from Verb Argument Structure Overgeneralization.

Directory of Open Access Journals (Sweden)

Ben Ambridge

Full Text Available Participants aged 5;2-6;8, 9;2-10;6 and 18;1-22;2 (72 at each age rated verb argument structure overgeneralization errors (e.g., *Daddy giggled the baby using a five-point scale. The study was designed to investigate the feasibility of two proposed construction-general solutions to the question of how children retreat from, or avoid, such errors. No support was found for the prediction of the preemption hypothesis that the greater the frequency of the verb in the single most nearly synonymous construction (for this example, the periphrastic causative; e.g., Daddy made the baby giggle, the lower the acceptability of the error. Support was found, however, for the prediction of the entrenchment hypothesis that the greater the overall frequency of the verb, regardless of construction, the lower the acceptability of the error, at least for the two older groups. Thus while entrenchment appears to be a robust solution to the problem of the retreat from error, and one that generalizes across different error types, we did not find evidence that this is the case for preemption. The implication is that the solution to the retreat from error lies not with specialized mechanisms, but rather in a probabilistic process of construction competition.

Impact of Basal Conditions on Grounding-Line Retreat

Science.gov (United States)

Koellner, S. J.; Parizek, B. R.; Alley, R. B.; Muto, A.; Holschuh, N.; Nowicki, S.

2017-12-01

current grounding-line position. Mixed rheology beds tend to mimic the retreat of the higher-exponent bed, a behavior enhanced over bumps as the stabilizing ridges tap into ice from local valleys. Thus, accounting for variable basal conditions in ice-sheet model projections is critical for improving both the timing and magnitude of retreat.

Modeling subglacial sediment discharge in 1-dimension: comparison with measurments and implications for glacial retreat

Science.gov (United States)

Delaney, I. A.; Werder, M.; Farinotti, D.

2017-12-01

In recent decades increased sedimentation rates have been observed in reservoirs downstream of some retreating glaciers. This material either originates from slopes recently exposed by glacier retreat and no longer stabilized by ice, or subglacially, where pressurized melt water transports sediments from the glacier bed. Some evidence suggests that recently exposed periglacial areas can stablize relatively quickly and in some catchments provides a smaller precentage of the total sediment compared to the subglacial environment. As a result, in order predict and forecast sediment yield from glaciated catchments as glaciers thin and thier hydrology evolves, a subglacial sediment transport model must be implemented. Here a simple 1-dimensional glacio-hydraulic model uses the Darcy-Weissbach relationship to determine shear-stress of presurized water on the glacier bed. This is coupled with a sediment transport relationship to determine quantity of discharged material from the glacier snout. Several tuning factors allow calibration and the model to reproduces processes known to occur subglacially, including seasonal evolution of sediment expulsion and deposition of sediment on adverse slopes of overdeepenings. To asses the model's application to real glaciers, sediment flux data has been collected from Gornergletscher, Aletschgletscher and Griesgletscher in the Swiss Alps over time-scales of up to decades. By calibrating to these data, the skill of the model in recreating sediment trends and volumes is assesed. The outputs capture annual erosion quanities relatively well, however, challenges exist in capturing inter-annual variations in sediment discharge. Many of the model's short comings relate to caputuring the spatial distribution of sediment throughout the glacier bed, which is particularing difficult in 1-dimension. However, this work suggests that a simple models can be used to predict subglacial sediment transport with reasonable ability. Additionally, further

Costs and effectiveness of fingolimod versus alemtuzumab in the treatment of highly active relapsing-remitting multiple sclerosis in the UK: re-treatment, discount, and disutility.

Science.gov (United States)

Montgomery, Stephen M; Kusel, Jeanette; Nicholas, Richard; Adlard, Nicholas

2017-09-01

Patients with relapsing-remitting multiple sclerosis (RRMS) treated with disease modifying therapies (DMTs) who continue to experience disease activity may be considered for escalation therapies such as fingolimod, or may be considered for alemtuzumab. Previous economic modeling used Markov models; applying one alternative technique, discrete event simulation (DES) modeling, allows re-treatment and long-term adverse events (AEs) to be included in the analysis. A DES was adapted to model relapse-triggered re-treatment with alemtuzumab and the effect of including ongoing quality-adjusted life year (QALY) decrements for AEs that extend beyond previous 1-year Markov cycles. As the price to the NHS of fingolimod in the UK is unknown, due to a confidential patient access scheme (PAS), a variety of possible discounts were tested. The interaction of re-treatment assumptions for alemtuzumab with the possible discounts for fingolimod was tested to determine which DMT resulted in lower lifetime costs. The lifetime QALY results were derived from modeled treatment effect and short- and long-term AEs. Most permutations of fingolimod PAS discount and alemtuzumab re-treatment rate resulted in fingolimod being less costly than alemtuzumab. As the percentage of patients who are re-treated with alemtuzumab due to experiencing a relapse approaches 100% of those who relapse whilst on treatment, the discount required for fingolimod to be less costly drops below 5%. Consideration of treatment effect alone found alemtuzumab generated 0.2 more QALYs/patient; the inclusion of AEs up to a duration of 1 year reduced this advantage to only 0.14 QALYs/patient. Modeling AEs with a lifetime QALY decrement found that both DMTs generated very similar QALYs with the difference only 0.04 QALYs/patient. When the model captured alemtuzumab re-treatment and long-term AE decrements, it was found that fingolimod is cost-effective compared to alemtuzumab, assuming application of only a modest level of

Nutrient biogeochemistry of the eastern Arabian Sea during the southwest monsoon retreat

Digital Repository Service at National Institute of Oceanography (India)

George, R; Muraleedharan, K.R; Martin, G.D.; Sabu, P.; Gerson, V.J.; Dineshkumar, P.K.; Nair, S.M.; Chandramohanakumar, N.; Nair, K.K.C.

and adjoining southeastern Arabian Sea. Curr Sci 96:364–375 Jyothibabu R, Madhu NV, Jayalakshmi KV, Balachandran KK, Shiyas CA, Martin GD, Nair KKC (2006) Impact of freshwater influx on microzooplankton mediated food web in a tropical estuary (Cochin backwaters... ARTICLE Nutrient biogeochemistry of the eastern Arabian Sea during the southwest monsoon retreat Rejomon George • K. R. Muraleedharan • G. D. Martin • P. Sabu • Vijay John Gerson • P. K. Dineshkumar • S. M. Nair • N. Chandramohanakumar • K. K. C. Nair...

Glacier Retreat in the Southern Peruvian Andes: Climate Change, Environmental Impacts, Human Perception and Social Response

Science.gov (United States)

Orlove, B.

2007-12-01

This paper presents results from recent environmental and anthropological research near glacierized areas in the department of Cusco, Peru, home to the well-known Quelccaya Ice Cap and to the peak of Ausangate (6384 m). Glaciers in the region are in negative mass balance, losing volume and area, with upslope movement of the glacier fronts. Somewhat paradoxically, flows in many streams close to the glaciers are reduced, particularly in the dry season, due to a shift in the seasonal distribution of melting, to increased evaporation and to increased percolation into newly-exposed sands and gravels. Associated with this reduction in flow is a desiccation of some anthropogenic and natural wetlands, reducing the availability of dry season forage to wild (vicuna) and domesticated (alpaca, llama) ruminants. Interviews and ethnographic observations with local populations of Quechua-speaking herders at elevations of 4500-5200 meters provide detailed comments on these changes. They have an extensive vocabulary of terms for glacial features associated with retreat. They link this treat with environmental factors (higher temperatures, greater winds that deposit dust on lower portions of glaciers) and with religious factors (divine punishment for human wrong-doing, failure of humans to respect mountain spirits). They describe a variety of economic and extra-economic impacts of this retreat on different spatial, social and temporal scales. Though they face other issues as well (threats of pollution from new mining projects, inadequacy of government services), glacier retreat is their principal concern. Many herders express extreme distress over this unprecedented threat to their livelihoods and communities, though a few propose responses - out-migration, the formation of an association of neighboring communities, development of irrigation works - that could serve as adaptations.

The retreatment of carboplatin via high-dose intraperitoneal chemotherapy in patients with a history of a hypersensitivity reaction

NARCIS (Netherlands)

Kerkhof, M.H.; Ruiz Zapata, A.M.; Bril, H.; Bleeker, M.C.G.; Belien, J.A.M.; Stoop, R.; Helder, M.N.

2014-01-01

A hypersensitivity reaction attributed to platinum-based chemotherapy is a relatively common occurrence. Hyperthermic intraperitoneal chemotherapy potentially facilitates the safe retreatment of platinum therapy following this complication. We describe 3 ovarian cancer patients who were successfully

Retreatment with sofosbuvir/velpatasvir in cirrhotic patients with genotype-4 who failed a previous interferon-free regimen: a case series.

Science.gov (United States)

Boglione, Lucio; Pinna, Simone Mornese; Lupia, Tommaso; Cariti, Giuseppe; Di Perri, Giovanni

2018-02-14

The novel available interferon (IFN)-free regimens significantly improved the sustained virological response (SVR) in patients with chronic hepatitis C (CHC), without important side effects and with shorter duration of treatment. In a subset of patients, however, the treatment failure (TF) was due to the presence of resistance-associated substitutions (RAS) that lead to virological breakthrough (BT) or relapse. We analysed in this case series the role of RAS on the TF in cirrhotic patients with genotype (GT)4, treated with a previous IFN-free regimen, and retreated with the combination of sofosbuvir (SOF)/velpatasvir (VEL) for 12 or 24 weeks, without ribavirin (RBV). We included in this analysis all patients with GT4 who failed a previous IFN-free treatment, with the presence of RAS at BT or relapse. All patients were retreated with a fixed combination of SOF/VEL for 12/24 weeks, without RBV. We evaluated the SVR and the MELD score change after the treatment. Seven patients were described. All were cirrhotic, Child-Pugh A (n=5), B (n=2); baseline RAS were detected in 4/7 subjects; at post-treatment detection, NS5 RAS were: F28S (n=1), Q30K (n=2), S30G (n=1), NS3 were: S122R (n=1), S122G (n=2), D168V (n=3). All retreated patients gained SVR. MELD score improved in all subjects with a median change of 3 points. No significant side effects or adverse events were reported. The combination SOF/VEL could be considered for the retreatment of cirrhotic GT4 patients who failed a previous IFN-free treatment with the presence of RAS in NS3 or NS5 regions.

Retreatment with sofosbuvir/velpatasvir in cirrhotic patients with genotype 4 who failed a previous interferon-free regimen: a case series.

Science.gov (United States)

Boglione, Lucio; Pinna, Simone Mornese; Lupia, Tommaso; Cariti, Giuseppe; Di Perri, Giovanni

2018-02-14

The novel available interferon (IFN)-free regimens significantly improved the sustained virological response (SVR) in patients with chronic hepatitis C (CHC), without important side-effects and with shorter duration of treatment. In a subset of patients, however, the treatment failure (TF) was due to the presence of resistance-associated substitutions (RAS) that lead to virological breakthrough (BT) or relapse. We analyzed in this case-series the role of RAS on the TF in cirrhotic patients with GT4, treated with a previous IFN-free regimen, and retreated with the combination of sofosbuvir (SOF)/velpatasvir (VEL) for 12 or 24 weeks, without ribavirin (RBV). We included in this analysis all patients with GT4 who failed a previous IFN-free treatment, with the presence of RAS at BT or relapse. All patients were retreated with a fixed combination of SOF/VEL for 12/24 weeks, without RBV. We evaluated the SVR and the MELD score change after the treatment. Seven patients were described. All were cirrhotic, Child-Pug A (n=5), B (n=2); baseline RAS were detected in 4/7 subjects; at post-treatment detection, NS5 RAS were: F28S (n=1), Q30K (n=2), S30G (n=1), NS3 were: S122R (n=1), S122G (n=2), D168V (n=3). All retreated patients gained the SVR. MELD score improved in all subjects with a median change of 3 points. No significant side-effects or adverse events were reported. The combination SOF/VEL could be considered for the retreatment of cirrhotic GT4 patients who failed a previous IFN-free treatment with the presence of RAS in NS3 or NS5 regions.

Feasibility and utility of re-treatment with 177Lu-DOTATATE in GEP-NENs relapsed after treatment with 90Y-DOTATOC

International Nuclear Information System (INIS)

Severi, Stefano; Sansovini, Maddalena; Ianniello, Annarita; Nicolini, Silvia; Caroli, Paola; Paganelli, Giovanni; Bodei, Lisa; Ibrahim, Toni; Di Iorio, Valentina; D'Errico, Vincenzo; Monti, Manuela

2015-01-01

Peptide receptor radionuclide therapy (PRRT) is a valid therapy for grade 1/2 gastroenteropancreatic (GEP) neuroendocrine neoplasms (NENs). Although a median progression-free survival (PFS) of more than 20 months is frequently observed, the majority of patients relapse after 2 - 3 years. In the present study, we investigated the use of low dosage re-treatment with 177 Lu-DOTATATE (Lu-PRRT) in patients with GEP-NENs who relapsed after treatment with 90 Y-DOTATOC (Y-PRRT). Upon tumour progression, 26 patients with a PFS of at least 12 months after Y-PRRT were consecutively enrolled in a phase II study of re-treatment with Lu-PRRT. All patients had preserved kidney and haematological parameters and received 14.8 - 18.5 GBq of Lu-PRRT in four or five cycles. The disease control rate (DCR), toxicity, PFS and prognostic factors were evaluated. Median total activity of Lu-PRRT was 16.5 GBq in five cycles. The DCR was 84.6 %, median PFS was 22 months (95 % CI 16 months - not reached) compared to 28 months (95 % CI 20 - 36 months) after Y-PRRT. Tumour burden and number of liver metastases were important prognostic factors. Toxicity was mild after Lu-PRRT re-treatment in the majority of patients, with only two patients with grade 2 and one with grade 3 bone marrow toxicity; one patient had grade 2 and one grade 3 renal toxicity. Patients with GEP-NEN who have previously responded to Y-PRRT are suitable candidates for Lu-PRRT re-treatment on progression. Although our sample size was limited, low-dosage Lu-PRRT was safe, and led to DCR and PFS rates comparable with those observed when Y-PRRT was used as primary treatment. (orig.)

Potential of the solid-Earth response for limiting long-term West Antarctic Ice Sheet retreat

Science.gov (United States)

Konrad, Hannes; Sasgen, Ingo; Pollard, David; Klemann, Volker

2016-04-01

The West Antarctic Ice Sheet (WAIS) is assumed to be inherently unstable because it is grounded below sea level in a large part, where the bedrock deepens from today's grounding line towards the interior of the ice sheet. Idealized simulations have shown that bedrock uplift due to isostatic adjustment of the solid Earth and the associated sea-level fall may stop the retreat of such a marine-based ice sheet (Gomez et al., 2012). Here, we employ a coupled model for ice-sheet dynamics and solid-Earth dynamics, including a gravitationally consistent description of sea level, to investigate the influence of the viscoelastic Earth structure on the WAIS' future stability (Konrad et al. 2015). For this, we start from a steady-state condition for the Antarctic Ice Sheet close to present-day observations and apply atmospheric and oceanic forcing of different strength to initiate the retreat of the WAIS and investigate the effect of the viscoelastic deformation on the ice evolution for a range of solid-Earth rheologies. We find that the climate forcing is the primary control on the occurrence of the WAIS collapse. However, for moderate climate forcing and a weak solid-Earth rheology associated with the West Antarctic rift system (asthenosphere viscosities of 3x10^19 Pa s or less), we find that the combined effect of bedrock uplift and gravitational sea-level fall limits the retreat to the Amundsen Sea embayment on millennial time scales. In contrast, a stiffer Earth rheology yields a collapse under these conditions. Under a stronger climate forcing, weak Earth structures do not prevent the WAIS collapse; however, they produce a delay of up to 5000 years in comparison to a stiffer solid-Earth rheology. In an additional experiment, we test the impact of sea-level rise from an assumed fast deglaciation of the Greenland Ice Sheet. In cases when the climatic forcing is too weak to force WAIS collapse by itself, the additional rise in sea-level leads to disintegration of the WAIS

Apical surgery vs apical surgery with simultaneous orthograde retreatment: A prospective cohort clinical study of teeth affected by persistent periapical lesion

Directory of Open Access Journals (Sweden)

Carlo Prati

2018-06-01

Full Text Available Aim: This prospective clinical study analyzed the 24-month outcome of conventional apical surgery retro-filled with calcium-silicate cement versus apical surgery with simultaneous orthograde retreatment by means of clinical and radiographic criteria. Materials and methods: This study included 83 teeth affected by persistent periapical lesions in 68 patients. Mean age was 52 years (median = 51 years; range 19–81 years. Twenty-eight cases were treated with apical surgery, 16 cases with apical surgery with simultaneous orthograde retreatment and 39 cases with orthograde retreatment in previously treated teeth established as control group. Periapical index score (PAI was used as radiographic criteria. Teeth were examined at 6 months, 1 and 2 years and classified as healed (without any symptoms and PAI ≤ 2, healing (without any symptoms and PAI = 3 or diseased (with symptoms or PAI ≥ 4 and not functional on the basis of radiographic and clinical criteria. At 24 months evaluation, healed and healing were considered as success and diseased and fracture as failure. Multilevel GLM model and an ordered logistic regression as statistical analysis was made with level of significance set at p < 0.05. Results: Total drop-out was 7% (n = 6. After 6–9 months, 6 teeth (3 from apical surgery, 2 from simultaneous treatment and 1 from orthograde retreatment were extracted for root fracture. Twenty-four-month success rate of apical surgery group was 78% (n = 17, apical surgery with simultaneous orthograde retreatment presented 81% (n = 10 and orthograde retreatment success was 80% (n = 24. There was no statistically difference between the groups at 24 months (p = 0.890. Conclusions: Both surgical techniques revealed a high percentage of healing, similar to that reported by previous studies. Apical surgery with simultaneous orthograde retreatment showed a faster healing after 12 months comparing to the control group. Riassunto: Scopo: In

Creating a specialist protein resource network: a meeting report for the protein bioinformatics and community resources retreat

NARCIS (Netherlands)

Babbitt, P.C.; Bagos, P.G.; Bairoch, A.; Bateman, A.; Chatonnet, A.; Chen, M.J.; Craik, D.J.; Finn, R.D.; Gloriam, D.; Haft, D.H.; Henrissat, B.; Holliday, G.L.; Isberg, V.; Kaas, Q.; Landsman, D.; Lenfant, N.; Manning, G.; Nagano, N.; Srinivasan, N.; O'Donovan, C.; Pruitt, K.D.; Sowdhamini, R.; Rawlings, N.D.; Saier, M.H., Jr.; Sharman, J.L.; Spedding, M.; Tsirigos, K.D.; Vastermark, A.; Vriend, G.

2015-01-01

During 11-12 August 2014, a Protein Bioinformatics and Community Resources Retreat was held at the Wellcome Trust Genome Campus in Hinxton, UK. This meeting brought together the principal investigators of several specialized protein resources (such as CAZy, TCDB and MEROPS) as well as those from

Yoga, Meditation and Mind-Body Health: Increased BDNF, Cortisol Awakening Response, and Altered Inflammatory Marker Expression after a 3-Month Yoga and Meditation Retreat.

Science.gov (United States)

Cahn, B Rael; Goodman, Matthew S; Peterson, Christine T; Maturi, Raj; Mills, Paul J

2017-01-01

Thirty-eight individuals (mean age: 34.8 years old) participating in a 3-month yoga and meditation retreat were assessed before and after the intervention for psychometric measures, brain derived neurotrophic factor (BDNF), circadian salivary cortisol levels, and pro- and anti-inflammatory cytokines. Participation in the retreat was found to be associated with decreases in self-reported anxiety and depression as well as increases in mindfulness. As hypothesized, increases in the plasma levels of BDNF and increases in the magnitude of the cortisol awakening response (CAR) were also observed. The normalized change in BDNF levels was inversely correlated with BSI-18 anxiety scores at both the pre-retreat ( r = 0.40, p mind-body integration and well-being. The increased BDNF levels observed is a potential mediator between meditative practices and brain health, the increased CAR is likely a reflection of increased dynamic physiological arousal, and the relationship of the dual enhancement of pro- and anti-inflammatory cytokine changes to healthy immunologic functioning is discussed.

Comparison of different retreatment techniques and root canal sealers: a scanning electron microscopic study

Directory of Open Access Journals (Sweden)

Neslihan Simsek

2014-05-01

Full Text Available The aim of this study was to evaluate the effectiveness of two retreatment techniques, in terms of the operating time and scanning electron microscopy (SEM results, in removing three different root canal sealers from root canals that were previously filled with gutta-percha. Sixty extracted single-rooted human premolars were divided into three groups and filled with iRoot SP, MM Seal, and AH Plus sealers, along with gutta-percha, through a lateral compaction technique. Root canal fillings of the samples were removed by ESI ultrasonic tips or R-Endo files. The time to reach the working length was recorded. Longitudinally sectioned samples were examined under SEM magnification. Each picture was evaluated in terms of the residual debris. Data were statistically analyzed with the Kruskall-Wallis test. No statistically significant differences were found in terms of operating time (p>0.05. Significant differences in the number of debris-free dentinal tubules were found among the root canal thirds, but this finding was not influenced by the experimental group (p < 0.05. Resin sealer tags were observed inside the dentinal tubules in the MM Seal group. Under the conditions of this study, it may be established that there was no difference among the sealers and retreatment techniques.

The future of ice sheets and sea ice: between reversible retreat and unstoppable loss.

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Notz, Dirk

2009-12-08

We discuss the existence of cryospheric "tipping points" in the Earth's climate system. Such critical thresholds have been suggested to exist for the disappearance of Arctic sea ice and the retreat of ice sheets: Once these ice masses have shrunk below an anticipated critical extent, the ice-albedo feedback might lead to the irreversible and unstoppable loss of the remaining ice. We here give an overview of our current understanding of such threshold behavior. By using conceptual arguments, we review the recent findings that such a tipping point probably does not exist for the loss of Arctic summer sea ice. Hence, in a cooler climate, sea ice could recover rapidly from the loss it has experienced in recent years. In addition, we discuss why this recent rapid retreat of Arctic summer sea ice might largely be a consequence of a slow shift in ice-thickness distribution, which will lead to strongly increased year-to-year variability of the Arctic summer sea-ice extent. This variability will render seasonal forecasts of the Arctic summer sea-ice extent increasingly difficult. We also discuss why, in contrast to Arctic summer sea ice, a tipping point is more likely to exist for the loss of the Greenland ice sheet and the West Antarctic ice sheet.

Orthograde retreatment failure with extruded MTA apical plug in a large periradicular lesion followed by surgical intervention: case report.

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Brito-Junior, Manoel; Faria-e-Silva, Andre Luis; Quintino, Alex Carvalho; Moreira-Junior, Gil; Geber, Mauro; Camilo, Carla Cristina; Soares, Janir Alves

2012-01-01

Absence of periapical healing after orthograde retreatment using an apical plug with mineral trioxide aggregate (MTA) can require surgical intervention. A patient with a root-filled maxillary central incisor with chronic apical periodontitis and sinus tract was referred for endodontic retreatment. Excessive apical enlargement was verified, indicating an MTA apical plug placement; however, an unintentional extrusion of MTA occurred during this step. The root canal was filled with gutta-percha and sealer, and periodic recalls were scheduled. The sinus tract was observed after six months and the lesion remained unaltered, although the extruded MTA had resorbed; therefore, an apicoectomy and retrograde root-end filling with MTA were performed. Absence of sinus tract, normal clinical aspect, and complete repair of the lesion were observed at the two-year follow-up.

Efficacy of D-RaCe and ProTaper Universal Retreatment NiTi instruments and hand files in removing gutta-percha from curved root canals - a micro-computed tomography study.

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Rödig, T; Hausdörfer, T; Konietschke, F; Dullin, C; Hahn, W; Hülsmann, M

2012-06-01

To compare the efficacy of two rotary NiTi retreatment systems and Hedström files in removing filling material from curved root canals. Curved root canals of 57 extracted teeth were prepared using FlexMaster instruments and filled with gutta-percha and AH Plus. After determination of root canal curvatures and radii in two directions, the teeth were assigned to three identical groups (n = 19). The root fillings were removed with D-RaCe instruments, ProTaper Universal Retreatment instruments or Hedström files. Pre- and postoperative micro-CT imaging was used to assess the percentage of residual filling material as well as the amount of dentine removal. Working time and procedural errors were recorded. Data were analysed using analysis of covariance and analysis of variance procedures. D-RaCe instruments were significantly more effective than ProTaper Universal Retreatment instruments and Hedström files (P ProTaper group, four instrument fractures and one lateral perforation were observed. Five instrument fractures were recorded for D-RaCe. D-RaCe instruments were associated with significantly less residual filling material than ProTaper Universal Retreatment instruments and hand files. Hedström files removed significantly less dentine than both rotary NiTi systems. Retreatment with rotary NiTi systems resulted in a high incidence of procedural errors. © 2012 International Endodontic Journal.

Antimicrobial usage and risk of retreatment for mild to moderate clinical mastitis cases on dairy farms following on-farm bacterial culture and selective therapy.

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McDougall, S; Niethammer, J; Graham, E M

2018-03-01

To assess antimicrobial usage for treatment of mild to moderate clinical mastitis, and risk of retreatment, following implementation of an on-farm bacterial culture system and selective therapy based on culture results, and to assess compliance with treatment decision tree protocols and the level of agreement between results from on-farm culture and laboratory-based microbiology methods. Herdowners from seven dairy herds were asked to collect milk samples from cases of mild to moderate clinical mastitis between July 2015 and May 2016. All samples were cultured on-farm using a commercially available selective media and were also submitted for laboratory-based culture. Within sequential pairs of cows with mastitis, half were assigned to be treated without regard to culture results (Blanket group), and half were treated based on the on-farm culture results (Selective group) according to decision tree diagrams provided to the farmers. Culture results, treatments, and retreatments for clinical mastitis were recorded. The sum of the daily doses of antimicrobials used per cow, the number of retreatments and interval to first retreatment were compared between treatment groups. The geometric mean sum of daily doses for quarters assigned to the Selective (1.72 (95% CI=1.55-1.90)) group was lower than for the Blanket (2.38 (95% CI=2.17-2.60)) group (p=0.005). The percentage of cows retreated for clinical mastitis did not differ between the Selective (21.7 (95% CI=10.5-25.9)%) and Blanket (26.1 (95% CI=20.9-31.3)%) groups (p=0.13), and there was no difference between groups in the hazard that cows would be retreated within 60 days of enrolment (hazard ratio=0.82 (95% CI=0.39-1.69); p=0.59). Compliance with the treatment protocols was higher amongst quarters assigned to the Selective (199/233; 85.4%) compared with the Blanket (171/249; 68.7%) group (p<0.001), and varied between farms from 64-94%. The overall agreement between results from on-farm and laboratory culture was 188

Rate of bedrock channel incision by waterfall retreat and landscape response constrained by cosmogenic 3He, Kauai, Hawaii

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Mackey, B. H.; Lamb, M. P.; Scheingross, J. S.; Farley, K. A.

2011-12-01

Channel incision and knickpoint retreat are the drivers of landscape evolution, yet we are still challenged to quantify the rate and processes by which rivers cut into rock. The Napali Coast on the northwestern side of Kauai, Hawaii, has multiple linear channels incising >200 m into the shield volcano surface. The channels have well-constrained initial conditions, including original topography, and relatively uniform layered basalt of known age (~4.5 Ma), which have attracted previous studies of channel evolution (e.g., Seidl et al., 1994, 1997). Many channels feature prominent waterfalls, although the mechanism of knickpoint initiation (submarine landslide vs cliff erosion) and subsequent retreat remain ambiguous. Motivated by these knowledge gaps and recent advances in cosmogenic helium geochronology, we revisited the Kaulaula Valley, a 9 km long narrow valley, beheaded on its upslope extent by the Waimea Canyon, and ending near the coast at the northern Mana Plain. Four kilometers up the canyon is a prominent 40 m high vertical knickpoint, dividing the valley into strongly contrasting geomorphic domains. The boulder-lined channel below the knickpoint is linear, steep (15%), and confined to a narrow valley with steep rocky cliffs (average slope 31°). Large, >2 m diameter angular boulders in the lower section of channel show evidence of mobility from debris flows. Above the knickpoint, average channel gradient is reduced (9%), bed load is much finer, and convex, soil-mantled hillslopes have a consistently lower mean slope of 18°. We constrained the exposure age of 18 features (in-channel boulders, stable boulders on terraces, and in-channel bedrock) along the length of the channel, by analysis of cosmogenic 3He in olivine phenocrysts. Cosmogenic exposure ages are oldest near the coast (80 ka) and systematically decrease with upstream distance towards the waterfall (model of knickpoint retreat and downstream terrace abandonment advocated by Seidl (1997), and we

Reassessment of Colombia's tropical glaciers retreat rates: are they bound to disappear during the 2010–2020 decade?

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G. Poveda

2009-12-01

Full Text Available Clear-cut evidences of global environmental change in Colombia are discussed for diverse hydro-climatic records, and illustrated herein for increasing minimum temperature and decreasing annual maximum river flows records. As a consequence, eight tropical glaciers disappeared from the Colombian Andes during the 20th century, and the remaining six have experienced alarming retreat rates during the last decade. Here we report an updated estimation of retreat rates in the six remaining glacierized mountain ranges of Colombia for the period 1987–2007, using Landsat TM and TM+ imagery. Analyses are performed using detailed pre-processing, processing and post-processing satellite imagery techniques. Alarming retreat rates are confirmed in the studied glaciers, with an overall area shrinkage from 60 km² in 2002, to 55.4 km² in 2003, to less than 45 km² in 2007. Assuming such linear loss rate (~3 km² per year, for the near and medium term, the total collapse of the Colombian glaciers can be foreseen by 2022, but diverse physical mechanisms discussed herein would exacerbate the shrinkage processes, thus prompting us to forecast a much earlier deadline by the late 2010–2020 decade, long before the 100 years foreseen by the 2007 IPCC Fourth Assessment Report. This forecast demands detailed monitoring studies of mass and energy balances. Our updated estimations of Colombia's glacier retreat rates posse serious challenges for highly valuable ecosystem services, including water supply of several large cities and hundreds of rural settlements along the Colombian Andes, but also for cheap and renewable hydropower generation which provides 80% of Colombia's demand. Also, the identified changes threaten the survivability of unique and fragile ecosystems like paramos and cloud forests, in turn contributing to exacerbate social unrest and ongoing environmental problems in the tropical Andes which have been

Restoration and recovery of hurricane-damaged mangroves using the knickpoint retreat effect and tides as dredging tools.

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Bashan, Yoav; Moreno, Manuel; Salazar, Bernardo G; Alvarez, Leonardo

2013-02-15

In 2001, a hurricane moved a large sand dune, blocking the sole outlet channel of a mangrove. In the absence of daily tidal flow, the two ponds containing the mangrove vegetation evaporated, the secondary drainage channels were lost, and a salt crust formed on the bed of the ponds. The mangrove lost most of its trees and the remaining suffered from osmotic shock that led to defoliation. Restoration involved creating a knickpoint retreat (waterfall retreat effect) and tidal flow as a dredging mechanism to restore the outlet and form secondary channels in the ponds. During a very low tide, we deepened the mouth of the outlet channel by 1 m below high tide level to form a small waterfall when high tides receded. During successive tides, this one-step knickpoint deteriorated and formed a series of low rapids. With a steep gradient, the rapids retreated upstream into the ponds, first reopening the outlet channel and then carving new secondary channels in the pond mud flat. The excavation process of the outlet channel was repeated three times and was sufficient to effectively improve the hydrology of the entire pond system; allowing adequate flooding and draining of the mangrove ponds. Hydrology analysis tested by the Engelund-Hansen sediment transport formula established that the output of sediment from the ecosystem is greater than the input of sand into the mangroves. This is keeping the main channel continuously open. After eight years, tidal flow continues to keep the channels open; the salt crust has disappeared; the trees have recovered, and a large area of new vegetation has emerged. Copyright © 2012 Elsevier Ltd. All rights reserved.

Evaluation of debris extruded apically during the removal of root canal filling material using ProTaper, D-RaCe, and R-Endo rotary nickel-titanium retreatment instruments and hand files.

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Topçuoğlu, Hüseyin Sinan; Aktı, Ahmet; Tuncay, Öznur; Dinçer, Asiye Nur; Düzgün, Salih; Topçuoğlu, Gamze

2014-12-01

The aim of this study was to evaluate the amount of debris extruded apically during the removal of root canal filling material using ProTaper (Dentsply Maillefer, Ballaigues, Switzerland), D-RaCe (FKG Dentaire, La Chaux-de-Fonds, Switzerland), and R-Endo (Micro-Mega, Besançon, France) nickel-titanium (NiTi) rotary retreatment instruments and hand files. Sixty extracted single-rooted mandibular premolar teeth were prepared with K-files and filled with gutta-percha and AH Plus sealer (Dentsply DeTrey, Konstanz, Germany). The teeth were then randomly assigned to 4 groups (n = 15 for each group) for retreatment. The removal of canal filling material was performed as follows: hand files, ProTaper, D-RaCe, and R-Endo retreatment instruments. Debris extruded apically during the removal of canal filling material was collected into preweighed Eppendorf tubes. The tubes were then stored in an incubator at 70°C for 5 days. The weight of the dry extruded debris was established by subtracting the preretreatment and postretreatment weight of the Eppendorf tubes for each group. The data obtained were analyzed using 1-way analysis of variance and Tukey post hoc tests. All retreatment techniques caused the apical extrusion of debris. Hand files produced significantly more debris when compared with ProTaper, D-RaCe, and R-Endo rotary systems (P ProTaper, D-RaCe, and R-Endo retreatment systems (P > .05). The findings showed that during the removal of root canal filling material, rotary NiTi retreatment instruments used in this study caused less apical extrusion of debris compared with hand files. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

The efficacy of ProTaper Universal rotary retreatment instrumentation to remove single gutta-percha cones cemented with several endodontic sealers.

Science.gov (United States)

Ersev, H; Yilmaz, B; Dinçol, M E; Dağlaroğlu, R

2012-08-01

To evaluate residual root filling material following removal of three newly developed root canal sealers used with a matched-taper single-cone root filling technique and to compare the efficacy of ProTaper Universal rotary retreatment instruments with that of a conventional manual technique. The canals of 120 palatal roots in maxillary molar teeth were instrumented with EndoWave nickel-titanium rotary instruments and filled using Hybrid Root SEAL, EndoSequence BC Sealer, Activ GP system or AH Plus with matched-taper single gutta-percha cones. The root fillings were then removed with ProTaper Universal retreatment rotary instruments or a manual technique. Buccolingual and proximal digital radiographs of the roots were exposed to determine the area of remaining filling material in the coronal, middle and apical thirds. The area percentages of remaining filling material in each third and total canal area were calculated. Data were analysed statistically with Kruskal-Wallis and Mann-Whitney U-tests. The level of significance was set at PProTaper groups. When using gross radiographic criteria, the Activ GP was more effectively removed from root canals than AH Plus with hand instrumentation. Hybrid Root SEAL, EndoSequence BC Sealer and AH Plus were removed to a similar extent. ProTaper Universal retreatment instruments were as safe and effective as hand instruments in reaching the working length. © 2012 International Endodontic Journal.

Glacier retreat of the Tian Shan and its impact on the urban growth and environment evaluated from satellite remote sensing data

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Fu, B. H.; Guo, Q.; Yan, F.; Zhang, J.; Shi, P. L.; Ayinuer, M.; Xue, G. L.

2017-07-01

The retreat of mountain glaciers, notably in high Asia, provides evidence for the rise of global temperature. The mass balance is vital for the health of a glacier. If the amount of frozen precipitation in the accumulation zone exceeds the quantity of glacial ice loss due to melting or lies in the ablation zone, the glacier will advance. Conversely, if the accumulation is less than the ablation, the glacier will retreat. Glaciers in retreat will have negative mass balances, and if they do not reach an equilibrium between accumulation and ablation, will eventually disappear. Long-term changes of the mountain glaciers in the Tian Shan, Central Asia, are not well constrained. Analyses of satellite remote sensing data combined with the ground observations reveal a 37.5% decline of glaciered area from 1989 to 2014 in No.1 Glacier, the headwaters of the Urumqi River basin, Chinese Tian Shan, which could be linked to increased summer melting. The results show that the area of glaciers was reduced from 31.55 km2 in 18 August 1989 to 28.66 km2 in 24 August 1994 and 19.74 km2 in 31 August 2014. The glacier area was reduced by 0.47 km2/per year in recent 25 years since 1989, and the annual reduction was 1.5%. Meanwhile, the urban area of Urumqi, the biggest city of Xinjiang Uygur Autonomous Region, increased from 156 km2 in 1989 to 555 km2 in 2014. Correspondingly, the population of permanent residents increased from 1.06 million in 1989 to 3.53 million in 2014. We suggest that the decline of glacier area is driven primarily by summer melting and, possibly, linked to the combined effects of the global rise in temperatures and black carbon/CO2 emission from coal-fired power plants, cement plants and petroleum chemical plants from the nearby Urumqi and surrounding regions. The continuing retreat of glaciers will have a number of different quantitative impacts. Populations in the arid Central Asia regions are heavily dependent on snow and glacier melt for their irrigation and

Effect of tofacitinib withdrawal and re-treatment on patient-reported outcomes: results from a Phase 3 study in patients with moderate to severe chronic plaque psoriasis.

Science.gov (United States)

Griffiths, C E M; Vender, R; Sofen, H; Kircik, L; Tan, H; Rottinghaus, S T; Bachinsky, M; Mallbris, L; Mamolo, C

2017-02-01

Tofacitinib is an oral Janus kinase inhibitor being investigated for psoriasis. A Phase 3 withdrawal/re-treatment study (NCT01186744; OPT Retreatment) showed tofacitinib re-treatment was effective in patients with chronic plaque psoriasis. To describe the effects of tofacitinib withdrawal/re-treatment on health-related quality of life (HRQoL) and disease symptoms measured by patient-reported outcomes (PROs). The study was divided into initial treatment, treatment withdrawal, and re-treatment periods. Initial treatment: patients were randomized to receive tofacitinib 5 (n = 331) or 10 mg (n = 335) BID for 24 weeks. Treatment withdrawal: patients who achieved both ≥ 75% reduction in Psoriasis Area and Severity Index (PASI) score from baseline and Physician's Global Assessment of 'clear'/'almost clear' at Week (W)24 received placebo (withdrawal) or the previous dose (continuous treatment). Re-treatment: at relapse (> 50% loss of W24 PASI response) or at W40, patients received their initial tofacitinib dose. PROs included: Dermatology Life Quality Index (DLQI), Itch Severity Item (ISI), Short Form-36 (SF-36) and Patient's Global Assessment (PtGA). After initial treatment with tofacitinib 5 and 10 mg BID, substantial and significant improvements were reported for mean DLQI (baseline: 12.6 and 12.6; W24: 5.1 and 2.6) and ISI (baseline: 6.7 and 6.9; W24: 2.9 and 1.6). Patients continuously treated with tofacitinib 5 and 10 mg BID maintained those improvements through Week 56 (DLQI: 3.0 and 2.1; ISI: 2.3 and 1.4). By W40, patients withdrawn from tofacitinib 5 and 10 mg BID showed worsening in DLQI (5.0 and 6.2) and ISI (3.7 and 4.0) scores; improvements were regained upon re-treatment (W56, DLQI: 3.4 and 2.4; ISI: 2.2 and 1.6). Similar results were reported for PtGA and SF-36. Continuous tofacitinib treatment provided sustained improvement in HRQoL and disease symptoms. Patients randomized to treatment withdrawal lost initial improvements. Upon re-treatment, improvements

Is raised helicobacter pylori antibody titre enough to decide retreatment

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Bibi, S.; Ahmed, W.; Arif, A.; Alam, S.E.

2011-01-01

Background: Helicobacter pylori infection causes a rise in its antibodies which take almost a year to come to baseline following successful eradication treatment. Checking these values in between a year may give falsely high values and many patients may thus be over treated. Aims: To serially determine Helicobacter pylori antibody titres in patients after giving them triple therapy for H. pylori eradication and see how these values drop over time. Study type, Settings and duration: Longitudinal study conducted in Department of Gastroenterology and Hepatology, Pakistan Medical Research Council, Research Centre, Jinnah Post Graduate Medical Centre, Karachi, from May 2006 to April 2010. Subjects and Methods: Over the period of four years, 186 patients who were found positive for campylobacter like organism test during endoscopy were further tested for anti H. pylori IgG titre before being treated for H. pylori. Patients were given triple therapy comprising of Omeprazole (20 mg twice daily), Amoxicillin (1 gm twice daily) and Clarythromycin (500 mg twice daily) for a week and were followed at 1, 3, 6 and 12 months to check symptomatic relief and they were tested again for H.Pylori antibody titres. Data was collected on pre-designed proforma which included patient's demography, symptoms and diagnosis. Results: Out of 186 patients who had a positive campylobacter like organism test, 173 patients consented to participate in the study. Serology for H.Pylori was positive in 119(68%) cases. A decline in mean antibody titres was observed as 11%, 21.5%, 54.7% and 59.2% at 1, 3, 6 and 12 months respectively. Conclusions: Sensitivity of serology for diagnosing H. pylori infection is good but using these as a tool for monitoring response to treatment is doubtful. A slow drop in H.pylori antibodies was seen over 12 months and therefore, physicians are cautioned not to retreat the already treated cases till about one year post treatment. Policy message: H. pylori antibodies should

Calibrated prediction of Pine Island Glacier retreat during the 21st and 22nd centuries with a coupled flowline model

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Gladstone, Rupert M.; Lee, Victoria; Rougier, Jonathan; Payne, Antony J.; Hellmer, Hartmut; Le Brocq, Anne; Shepherd, Andrew; Edwards, Tamsin L.; Gregory, Jonathan; Cornford, Stephen L.

2012-06-01

A flowline ice sheet model is coupled to a box model for cavity circulation and configured for the Pine Island Glacier. An ensemble of 5000 simulations are carried out from 1900 to 2200 with varying inputs and parameters, forced by ocean temperatures predicted by a regional ocean model under the A1B ‘business as usual’ emissions scenario. Comparison is made against recent observations to provide a calibrated prediction in the form of a 95% confidence set. Predictions are for monotonic (apart from some small scale fluctuations in a minority of cases) retreat of the grounding line over the next 200 yr with huge uncertainty in the rate of retreat. Full collapse of the main trunk of the PIG during the 22nd century remains a possibility.

Potential to induce dentinal cracks during retreatment procedures of teeth treated with “Russian red”: An ex vivo study

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Eglė Nedzinskienė

2017-01-01

Conclusions: Retreatment methods had a damaging effect on the root dentin of teeth previously treated with resorcinol–formaldehyde resin. At magnification ×16, the efficacy of using the dye for the detection of cracks was higher than detection without the dye.

Risk factors associated with default among retreatment tuberculosis patients on DOTS in Paschim Medinipur district (West Bengal).

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Sarangi, S S; Dutt, D

2014-07-01

In India in 2010, 14.1% of retreatment of TB patients' treatment outcome was 'default'. Since 2002, in Paschim Midnapur District (West Bengal), it has been around 15-20%. To determine the timing, characteristics and risk factors associated with default among retreatment TB patients on DOTS. It was a case control study, conducted in six TB units (TU) of Paschim Midnapur District, which were selected by simple random sampling. Data was collected from treatment records of TUs/DTC. Data was also collected through interviews of the patients using the same pre-tested semi-structured questionnaire from 87 defaulters and 86 consecutively registered non-defaulters registered in first quarter, 2009 to second quarter, 2010. Median duration of treatment taken before default was 121 days (inter-quartile range of 64-176 days). Median number of doses of treatment taken before default was 36 (inter -quartile range of 26-63 doses). No retrieval action was documented in 57.5% cases. Retrieval was done between 0-7 days of missed doses in 29.9% cases. Multiple logistic regression analysis indicated the following important risk factors for default at 95% confidence interval: male-sex limit: [aOR 3.957 (1.162-13.469)], alcoholic inebriation[ aOR6.076 (2.088-17.675)], distance from DOT centre [aOR 4.066 (1.675-9.872)], number of missed doses during treatment [aOR 1.849 (1.282-2.669)] and no initial home visit [aOR 10.607 (2.286 -49.221)]. In Paschim Midnapur district, default of retreatment TB occurs mostly after a few doses in continuation phase. Initial home visit, patient provider meeting, retrieval action, community-based treatment as per RNTCP guidelines are required to uplift the programme.

Feasibility and utility of re-treatment with {sup 177}Lu-DOTATATE in GEP-NENs relapsed after treatment with {sup 90}Y-DOTATOC

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Severi, Stefano; Sansovini, Maddalena; Ianniello, Annarita; Nicolini, Silvia; Caroli, Paola; Paganelli, Giovanni [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Nuclear Medicine Unit, Meldola, FC (Italy); Bodei, Lisa [European Institute of Oncology, Division of Nuclear Medicine, Milan (Italy); Ibrahim, Toni [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Osteoncology and Rare Tumors Center, Meldola (Italy); Di Iorio, Valentina [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Oncology Pharmacy Laboratory, Meldola (Italy); D' Errico, Vincenzo [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Medical Physics Unit, Meldola (Italy); Monti, Manuela [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Unit of Biostatistics and Clinical Trials, Meldola (Italy)

2015-12-15

Peptide receptor radionuclide therapy (PRRT) is a valid therapy for grade 1/2 gastroenteropancreatic (GEP) neuroendocrine neoplasms (NENs). Although a median progression-free survival (PFS) of more than 20 months is frequently observed, the majority of patients relapse after 2 - 3 years. In the present study, we investigated the use of low dosage re-treatment with {sup 177}Lu-DOTATATE (Lu-PRRT) in patients with GEP-NENs who relapsed after treatment with {sup 90}Y-DOTATOC (Y-PRRT). Upon tumour progression, 26 patients with a PFS of at least 12 months after Y-PRRT were consecutively enrolled in a phase II study of re-treatment with Lu-PRRT. All patients had preserved kidney and haematological parameters and received 14.8 - 18.5 GBq of Lu-PRRT in four or five cycles. The disease control rate (DCR), toxicity, PFS and prognostic factors were evaluated. Median total activity of Lu-PRRT was 16.5 GBq in five cycles. The DCR was 84.6 %, median PFS was 22 months (95 % CI 16 months - not reached) compared to 28 months (95 % CI 20 - 36 months) after Y-PRRT. Tumour burden and number of liver metastases were important prognostic factors. Toxicity was mild after Lu-PRRT re-treatment in the majority of patients, with only two patients with grade 2 and one with grade 3 bone marrow toxicity; one patient had grade 2 and one grade 3 renal toxicity. Patients with GEP-NEN who have previously responded to Y-PRRT are suitable candidates for Lu-PRRT re-treatment on progression. Although our sample size was limited, low-dosage Lu-PRRT was safe, and led to DCR and PFS rates comparable with those observed when Y-PRRT was used as primary treatment. (orig.)

Research-retreat-recovery: A potential model for organization and completion of research projects. Experience from a neurosurgery department in a developing country.

Science.gov (United States)

Godil, Saniya Siraj; Kazim, Syed Faraz; Shamim, Muhammad Shahzad

2010-10-30

In the current era of biomedical research, it is imperative that every research study at an institution is properly organized, and frequently audited to streamline efforts and maintain standards. Recently, a research retreat was organized by the Section of Neurosurgery at Aga Khan University Hospital, Karachi, Pakistan, and following that a recovery team was made with the aim of recovering "lost in translation" research projects. In the realm of our experience, the current model is being proposed as a means for organization of departmental research. The "research" component of the model comprised compilation of an abstract book of all research work done within the section during the last five years. The "retreat" component of the model was intended with objectives of analysis of past research and generation of fresh ideas. The "recovery" component of the model was accomplished by formation of a research recovery team with the aim of recovering unfinished, and/or unpublished research projects. The abstract book comprised 103 abstracts: 52.4% original research studies, 12.6% review articles, and 34.9% case report/series. Only 8.7% abstracts were of basic science research whereas the remaining 91.3% were clinical research papers. Only 34% had been published in an article form in a biomedical research journal (51.4% in international journals and 48.6% in national journals); remaining papers were either in submission/preparation process or had been abandoned. As part of research recovery, 29.4% projects were recovered within 12 weeks of the retreat component. We conclude that the model of "research-retreat-recovery" is highly successful in the context of neurosurgery departments in developing countries without a proper research unit, and can result in better organization of departmental research, recovery of unfinished projects, and initiation of new research studies.

Efficacy of ProTaper retreatment system in root canals filled with gutta-percha and two endodontic sealers.

Science.gov (United States)

Só, Marcus Vinícius Reis; Saran, Caroline; Magro, Miriam Lago; Vier-Pelisser, Fabiana Vieira; Munhoz, Marcelo

2008-10-01

This study evaluated the efficacy of ProTaper Universal rotary retreatment system and hand files for filling material removal during retreatment and the influence of sealer type on the presence of filling debris in the reinstrumented canals. The canals of 60 palatal roots of first molars were obturated with gutta-percha and either a zinc oxide-eugenol-based or a resin-based sealer and reinstrumented: G1, EndoFill/hand files; G2, AH Plus/hand files; G3, EndoFill/ProTaper; G4, AH Plus/ProTaper. Roots were cleaved and examined with an optical microscope, and the amount of filling debris on canal walls was analyzed on digitized images. There was no significant difference (P > .05) among the root canal thirds within each group. G3 presented significantly more filling debris than G1 in the cervical third (P = .04). In the middle third, G2/G3/G4 showed more debris than G1 (P = .03). The techniques were similar (P = .64) in the apical third. All groups presented filling debris in the 3 canal thirds after reinstrumentation.

Selective embolization of unruptured intracranial aneurysms is associated with low retreatment rate

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Bandeira, Alexandra; Raphaeli, Guy [Erasme University Hospital, Department of Radiology, Neuroradiology Section, Brussels (Belgium); Erasme University Hospital, Interventional Neuroradiology Fellows, Brussels (Belgium); Baleriaux, Danielle [Erasme University Hospital, Department of Radiology, Neuroradiology Section, Brussels (Belgium); Bruneau, Michael; Witte, Olivier De [Erasme University Hospital, Neurosurgery, Brussels (Belgium); Lubicz, Boris [Erasme University Hospital, Department of Radiology, Neuroradiology Section, Brussels (Belgium); Hopital Erasme, Service de Radiologie, Brussels (Belgium)

2010-02-15

To report long-term imaging findings of 101 patients with 129 unruptured intracranial aneurysms (UIA) treated by embolization. A retrospective review of our prospectively maintained database identified all patients with an UIA treated by embolization with coils only and with a minimal 12-month imaging follow-up. The clinical charts, procedural data, and angiographic results were reviewed. Between March 2004 and June 2009, 101 patients with 129 UIA were identified (71 women/30 men, mean age = 51.4 years). Ninety-four aneurysms (73%) were large (10-25 mm), and 35 (27%) were small (<10 mm). Aneurysms mean size was 10.7 mm (median, 9 mm; range 3-22 mm); 87 UIA (67.5%) had a small neck (<4 mm or neck/sac ratio < 0.7), and 42 (32.5%) had a wide neck ({>=}4 mm or neck/sac ratio {>=} 0.7). Selective coiling with bare/coated coils was performed in 125 cases and four cases, respectively. The balloon-assisted technique was used in 47 cases (36.4%). Only one patient experienced a symptomatic complication (thromboembolism) and kept a slight hemiparesis. Immediate results included 77 complete occlusions (59.7%), 45 neck remnants (34.9%), and 7 incomplete occlusions (5.4%). Mean imaging follow-up of 32 months showed 104 stable occlusions (80.6%), 12 further thrombosis (9.3%), 7 major recanalizations (5.4%), and 6 minor recanalizations (4.7%). Retreatment was required in seven wide-necked and/or large aneurysms including four treated with coated coils. No bleeding occurred during follow-up. Selective embolization of UIA is associated with stable long-term anatomical results and low retreatment rate. (orig.)

The antimicrobial effectiveness of photodynamic therapy used as an addition to the conventional endodontic re-treatment: a clinical study.

Science.gov (United States)

Jurič, Ivona Bago; Plečko, Vanda; Pandurić, Dragana Gabrić; Anić, Ivica

2014-12-01

The purpose of the study was to evaluate the efficacy of antimicrobial photodynamic therapy (aPDT) used as an adjunct to the endodontic re-treatment in the eradication of microorganisms from previously filled root canals. The study sample consisted of 21 randomly selected patients with root filled and infected root canal system with chronic apical periodontitis on incisors or canines, who have had previously endodontic treatment. Microbiological samples from the root canals were collected after accessing the canal, following the endodontic re-treatment and after the aPDT procedure. During instrumentation, the root canals were irrigated with 2.5% sodium hypochlorite (NaOCl), and the final irrigation protocol included 17% ethylenediaminetetraacetic acid followed by NaOCl. Root canals were filled with a phenothiazinium chloride and irradiated with a diode laser (λ=660 nm, 100 mW) for 1 min. Microbiological samples from the root canals were cultivated on selective plates, and the identification was done by micromorphology, macromorphology and different API strips as well as bacterial counts (colony forming units). Fourteen bacteria species were isolated from the root canals initially, with a mean value of 4.57 species per canal. Although endodontic re-treatment alone produced a significant reduction in the number of bacteria species (pendodontic treatment and aPDT was statistically more effective (proot canals of 11 teeth. The results indicated that the aPDT used as an adjunct to the conventional endodontic therapy achieved a significant further reduction of intracanal microbial load. Copyright © 2014 Elsevier B.V. All rights reserved.

Retarded deglaciation of north-Spitsbergen fjords during the last glacial - an example of bathymetric controls on the dynamics of retreating glaciers

Science.gov (United States)

Forwick, M.; Vorren, T. O.; Hass, H.; Vogt, C. M.

2012-12-01

North and west Spitsbergen fjords acted as pathways for fast-flowing ice streams during the last glacial (e.g. Ottesen et al., 2005). The deglaciation of west Spitsbergen fjords occurred stepwise and the ice retreat terminated around 11,200 cal. years BP (calendar years before the present; e.g. Forwick & Vorren, 2009, 2011, and references therein; Baeten et al., 2010). However, the deglaciation dynamics and chronology of north Spitsbergen fjords still remain poorly understood. We present swath-bathymetry, high-resolution seismic data and two sediment cores from the approx. 110 km long, N-S oriented Wijdefjorden-Austfjorden fjord system, the largest fjord system on northern Spitsbergen. The data indicate that - as in the fjords on west Spitsbergen - multiple halts and/or readvances interrupted the retreat of the ice front during the final phase of the last glacial. However, even though the study area and several west Spitsbergen fjords are fed by the same glacier source (the ice field Lomonosovfonna), the final deglaciation of Wijdefjorden-Austfjorden took place after 9300 cal. years BP, i.e. at least approx. 2000 years later than in the west. We assume that the retarded deglaciation in the north is mainly related to the fjord bathymetry, i.e. a more than 35 km wide and up to 60 m high area in the central parts of the study area (approx. 45 km beyond the present fjord head) that acted as pinning point for the grounded glacier. Multiple, relatively large and partly stacked moraine ridges and sediment wedges are suggested to reflected that the ice front retreated slowly across this shallow area and that repeated readvances interrupted this retreat. The absence of larger sediment wedges in the deeper parts between the shallow area and the fjord head may indicate that the final retreat occurred relatively rapid. References: Baeten, N.J., Forwick, M., Vogt, C. & Vorren, T.O., 2010. Late Weichselian and Holocene sedimentary environments and glacial activity in

Effect of retreating sea ice on Arctic cloud cover in simulated recent global warming

Directory of Open Access Journals (Sweden)

M. Abe

2016-11-01

Full Text Available This study investigates the effect of sea ice reduction on Arctic cloud cover in historical simulations with the coupled atmosphere–ocean general circulation model MIROC5. Arctic sea ice has been substantially retreating since the 1980s, particularly in September, under simulated global warming conditions. The simulated sea ice reduction is consistent with satellite observations. On the other hand, Arctic cloud cover has been increasing in October, with about a 1-month lag behind the sea ice reduction. The delayed response leads to extensive sea ice reductions because the heat and moisture fluxes from the underlying open ocean into the atmosphere are enhanced. Sensitivity experiments with the atmospheric part of MIROC5 clearly show that sea ice reduction causes increases in cloud cover. Arctic cloud cover increases primarily in the lower troposphere, but it decreases in the near-surface layers just above the ocean; predominant temperature rises in these near-surface layers cause drying (i.e., decreases in relative humidity, despite increasing moisture flux. Cloud radiative forcing due to increases in cloud cover in autumn brings an increase in the surface downward longwave radiation (DLR by approximately 40–60 % compared to changes in clear-sky surface DLR in fall. These results suggest that an increase in Arctic cloud cover as a result of reduced sea ice coverage may bring further sea ice retreat and enhance the feedback processes of Arctic warming.

Sub-ice-shelf sediments record history of twentieth-century retreat of Pine Island Glacier

OpenAIRE

Smith, J.A.; Andersen, T.J.; Shortt, M.; Gaffney, A.M.; Truffer, M.; Stanton, T.P.; Bindschadler, R.; Dutrieux, P.; Jenkins, A.; Hillenbrand, C.-D.; Ehrmann, W.; Corr, H.F.J.; Farley, N.; Crowhurst, S.; Vaughan, D.G.

2016-01-01

The article of record as published may be found at http://dx.doi.org/10.1038/nature20136 The West Antarctic Ice Sheet is one of the largest potential sources of rising sea levels. Over the past 40 years, glaciers flowing into the Amundsen Sea sector of the ice sheet have thinned at an accelerating rate, and several numerical models suggest that unstable and irreversible retreat of the grounding line—which marks the boundary between grounded ice and floating ice shelf—is underway. Under...

Late effects of radiation on the lumbar spinal cord of guinea pigs: Re-treatment tolerance

International Nuclear Information System (INIS)

Mason, K.A.; Withers, H.R.; Chiang, Chi-Shiun

1993-01-01

Using a guinea pig model of lumbar myelopathy, various factors affecting the tolerance of spinal cord to irradiation were assessed: (a) extent of initial injury; (b) time interval between priming and test doses; and (c) animal age at the time of initial radiation treatment. A 3 cm section of lumbar spinal cord of guinea pigs was irradiated with fractionated doses of 4.5 Gy gamma rays given as 9 fractions per week. Guinea pigs were primed with 9 x 4.5 Gy in 7 days which is 60% of the ED 50 for a continuous course of treatment. After 28 or 40 weeks, animal were retreated with 6-14 fractions of 4.5 Gy. Animals were observed for 2 years following the priming dose and both the incidence and latency of myelopathy recorded. Young adult guinea pigs (8 wk old) showed both a decreased radiation tolerance and latency compared to old individuals (40 wk old). At 28 or 40 wk after 9 x 4.5 Gy, only about 8% of the initial injury was remembered in young adult guinea pigs. The amount of residual injury was dependent on the initial damage as a proportion of the tolerance dose. The spinal cord shows a greater capacity for long-term recovery than generally appreciated and re-treatment doses clinically prescribed may be lower than necessary. 8 refs., 3 figs., 2 tabs

"Managed Retreat" in Response to Superstorm Sandy: The Oakwood Beach Story

Science.gov (United States)

Tirone, J.

2017-12-01

This presentation shares lessons learned from firsthand experience of the home buyout process in New York City after Superstorm Sandy. Many have described Sandy as "the perfect storm" from a meteorological perspective, but it was also the perfect storm from a government-buyout perspective. For a buyout to work in New York City, with its high property values and dense housing and population, many conditions had to be in place before the storm. Before Sandy hit, Oakwood Beach on Staten Island had already had enough. Hurricane Isaac flooded streets and basements in 2010, followed by Hurricane Irene in 2011. Many residents of this multi-generational neighborhood had just finished fixing their homes. A few years before, a brush fire spread through the invasive and highly flammable Phragmites reeds, destroying a protective berm installed by the Army Corps of Engineers in 2000 and threatening to damage many homes. An aerial view would show how these homes incredulously sat in the middle of a marsh, a marsh designated as part of the Bluebelt wetlands storm water management system by New York City's Department of Environmental Protection. Even more incredulously, while New York City was buying up unimproved lots to expand the Bluebelt to improve drainage for inland homes, the City was also issuing building permits to developers - sometimes for lots directly in the Bluebelt's path. Welcome to Staten Island, where the political influence of developers made any effort to retreat from the waterfront especially difficult and contentious. Before the storm, no one knew what a buyout was, never mind how to go about seeking one. For the most part, this included local officials. Managed retreat is typically understood as a top-down directive, but in this case the buyout plan was initiated from the bottom up by eight ordinary citizens who used research, trust, and networking to get their voices heard and, against all odds, to drive a highly successful State-supported buyout program.

Comparative analysis of efficacy and cleaning ability of hand and rotary devices for gutta-percha removal in root canal retreatment: an in vitro study.

Science.gov (United States)

Reddy, Narender; Admala, Shilpa Reddy; Dinapadu, Sainath; Pasari, Srikanth; Reddy, Manoranjan P; Rao, M S Rama

2013-07-01

To evaluate the efficacy and cleaning ability of Hedstrom files, and ProTaper retreatment instruments in removing gutta-percha from root canals with and without xylene as solvent. Sixty extracted single rooted human teeth were selected and decoronated, straight access established working length determined 1 mm short of canal, chemomechanical preparation done and obturated with guttapercha and AH plus sealer. Samples were stored for 1 week in humidifier divided into four groups of 15 teeth each. • Group I: Hedstrom files without xylene. • Group II: Hedstrom files with xylene. • Group III: ProTaper retreatment instruments without xylene. • Group IV: ProTaper retreatment instruments with xylene. and the following criteria were assessed - Time taken for initial plunge of instrument into guttapercha. - Time taken for complete removal of gutta-percha to reach working length - Ability of H files and ProTaper retreatment files with/ without xylene to remove gutta-percha in coronal, middle and apical 1/3 of canal. The teeth were grooved in labiolingual cross section, observed under a steromicroscope and scored according to gutta-percha debris left in the canal. Results were evaluated using ANOVA test and multiple comparisons done using Scheffe test. The least time to reach working length was found with group IV followed by groups III, II and group I respectively. Also the fastest way to remove maximum gutta-percha was group IV followed by groups III, II, and I respectively with a statistically significant difference among all groups. Apical 1/3 has more amount of remaining gutta-percha debris than middle and coronal 1/3 in all groups. The amount of gutta-percha debris in apical 1/3 was least in group IV followed by groups III, II and I respectively. The better performance of ProTaper rotary instruments has been attributed to their special flute design which tends to pull gutta-percha coronally directing it toward orifice. Also the movements of engine driven

Effect of Intracanal Medication with Calcium Hydroxide and 1% Chlorhexidine in Endodontic Retreatment Cases with Periapical Lesions: An In Vivo Study

Directory of Open Access Journals (Sweden)

Ertugrul Ercan

2007-01-01

Conclusion: Our results suggest that a combination of Ca(OH2 and 1% CHX can be successfully used as intracanal medicament for disinfection in endodontic retreatment cases with periapical lesions. [J Formos Med Assoc 2007;106(3:217-224

Extinction and ecological retreat in a community of primates

Energy Technology Data Exchange (ETDEWEB)

Crowley, B. E.; Godfrey, L. R.; Guilderson, T. P.; Zermeno, P.; Koch, P. L.; Dominy, N. J.

2012-05-23

The lemurs of Madagascar represent a prodigious adaptive radiation. At least 17 species ranging from 11 to 160 kg have become extinct during the past 2000 years. The effect of this loss on contemporary lemurs is unknown. The concept of competitive release favours the expansion of living species into vacant niches. Alternatively, factors that triggered the extinction of some species could have also reduced community-wide niche breadth. Here, we use radiocarbon and stable isotope data to examine temporal shifts in the niches of extant lemur species following the extinction of eight large-bodied species. We focus on southwestern Madagascar and report profound isotopic shifts, both from the time when now-extinct lemurs abounded and from the time immediately following their decline to the present. Unexpectedly, the past environments exploited by lemurs were drier than the protected (albeit often degraded) riparian habitats assumed to be ideal for lemurs today. Neither competitive release nor niche contraction can explain these observed trends. We develop an alternative hypothesis: ecological retreat, which suggests that factors surrounding extinction may force surviving species into marginal or previously unfilled niches.

Successful retreatment with sofosbuvir plus ledipasvir for cirrhotic patients with hepatitis C virus genotype 1b, who discontinued the prior treatment with asunaprevir plus daclatasvir: A case series and review of the literature

Science.gov (United States)

Haga, Yuki; Kanda, Tatsuo; Yasui, Shin; Nakamura, Masato; Ooka, Yoshihiko; Takahashi, Koji; Wu, Shuang; Nakamoto, Shingo; Arai, Makoto; Chiba, Tetsuhiro; Maruyama, Hitoshi; Yokosuka, Osamu; Takada, Nobuo; Moriyama, Mitsuhiko; Imazeki, Fumio; Kato, Naoya

2018-01-01

Background Interferon-free treatment results in higher sustained virologic response (SVR) rates, with no serious adverse events in hepatitis C virus (HCV)-infected patients. However, in some patients with treatment-failure in HCV NS5A inhibitor-including interferon-free regimens, the treatment-emergent HCV NS5A resistance-associated variants (RAVs), which are resistant to interferon-free retreatment including HCV NS5A inhibitors, are observed. In HCV-infected Japanese patients with daclatasvir and asunaprevir treatment failure, retreatment with sofosbuvir and ledipasvir could lead to only ∼70% SVR rates. Case summary Three HCV genotype (GT)-1b-infected cirrhotic patients who discontinued the combination of daclatasvir and asunaprevir due to adverse drug reactions within 4 weeks; retreatment with sofosbuvir and ledipasvir combination could result in SVR in these patients without RAVs. One HCV GT-1b-infected cirrhotic patient who discontinued the combination of daclatasvir and asunaprevir due to viral breakthrough at week 10; retreatment with sofosbuvir and ledipasvir combination for this patient with the treatment-emergent HCV NS5A RAV-Y93H resulted in viral relapse at week 4 after the end of the treatment. Conclusion Retreatment with sofosbuvir and ledipasvir is effective for HCV GT-1b patients who discontinue the combination of daclatasvir and asunaprevir within 4 weeks. The treatment response should be related to the existence of treatment-emergent HCV NS5A RAVs, but may not be related to the short duration of treatment. PMID:29435197

In Review (Geology): Alpine Landscape Evolution Dominated by Cirque Retreat

Science.gov (United States)

Oskin, Michael; Burbank, Doug

2005-01-01

Despite the abundance in alpine terrain of glacially dissected landscapes, the magnitude and geometry of glacial erosion can rarely be defined. In the eastern Kyrgyz Range, a widespread unconformity exhumed as a geomorphic surface provides a regional datum with which to calibrate erosion. As tectonically driven surface uplift has progressively pushed this surface into the zone of ice accumulation, glacial erosion has overprinted the landscape. With as little as 500 m of incision into rocks underlying the unconformity, distinctive glacial valleys display their deepest incision adjacent to cirque headwalls. The expansion of north-facing glacial cirques at the expense of south-facing valleys has driven the drainage divide southwards at rates up to 2 to 3 times the rate of valley incision. Existing ice-flux-based glacial erosion rules incompletely model expansion of glacial valleys via cirque retreat into the low-gradient unconformity remnants. Local processes that either directly sap cirque headwalls or inhibit erosion down-glacier appear to control, at least initially, alpine landscape evolution.

Drainage of ice-dammed lakes and glacier retreat - a link

DEFF Research Database (Denmark)

Kjeldsen, Kristian Kjellerup; Kjaer, K. H.; Rysgaard, Søren

2011-01-01

surface freshwater run-off is found in the top of the water column in the fjord while sub-glacial meltwater is entrained deeper in the water column. The latter is highly important as this colder buoyant freshwater is pushed to the water surface followed by a compensating deeper landward current bringing...... in the fjord. The large quantity of buoyant freshwater changed the osmotic pressure and pushed redfish to the water surface causing them to die from divers disease. Further investigation suggested that three ice-dammed lakes adjacent to the Narssap Sermia glacier had drained within the previous year. Analysis......-30 times the volume of an ice-dammed lake prior to drainage. The warm water influx in turn causes the glacier to retreat and to gradually become thinner which feeds back to an increase in drainage events of ice-dammed lakes over time. On a larger scale the feedback mechanism between the drainage of lakes...

Rituximab Extended Schedule or Re-Treatment Trial for Low–Tumor Burden Follicular Lymphoma: Eastern Cooperative Oncology Group Protocol E4402

Science.gov (United States)

Kahl, Brad S.; Hong, Fangxin; Williams, Michael E.; Gascoyne, Randy D.; Wagner, Lynne I.; Krauss, John C.; Habermann, Thomas M.; Swinnen, Lode J.; Schuster, Stephen J.; Peterson, Christopher G.; Sborov, Mark D.; Martin, S. Eric; Weiss, Matthias; Ehmann, W. Christopher; Horning, Sandra J.

2014-01-01

Purpose In low–tumor burden follicular lymphoma (FL), maintenance rituximab (MR) has been shown to improve progression-free survival when compared with observation. It is not known whether MR provides superior long-term disease control compared with re-treatment rituximab (RR) administered on an as-needed basis. E4402 (RESORT) was a randomized clinical trial designed to compare MR against RR. Patients and Methods Eligible patients with previously untreated low–tumor burden FL received four doses of rituximab, and responding patients were randomly assigned to either RR or MR. Patients receiving RR were eligible for re-treatment at each disease progression until treatment failure. Patients assigned to MR received a single dose of rituximab every 3 months until treatment failure. The primary end point was time to treatment failure. Secondary end points included time to first cytotoxic therapy, toxicity, and health-related quality of life (HRQOL). Results A total of 289 patients were randomly assigned to RR or MR. With a median follow-up of 4.5 years, the estimated median time to treatment failure was 3.9 years for patients receiving RR and 4.3 years for those receiving MR (P = .54). Three-year freedom from cytotoxic therapy was 84% for those receiving RR and 95% for those receiving MR (P = .03). The median number of rituximab doses was four patients receiving RR and 18 for those receiving MR. There was no difference in HRQOL. Grade 3 to 4 toxicities were infrequent in both arms. Conclusion In low–tumor burden FL, a re-treatment strategy uses less rituximab while providing disease control comparable to that achieved with a maintenance strategy. PMID:25154829

New details about the LGM extent and subsequent retreat of the West Antarctic Ice Sheet from the easternmost Amundsen Sea Embayment shelf

Science.gov (United States)

Klages, J. P.; Hillenbrand, C. D.; Kuhn, G.; Smith, J. A.; Graham, A. G. C.; Nitsche, F. O.; Frederichs, T.; Arndt, J. E.; Gebhardt, C.; Robin, Z.; Uenzelmann-Neben, G.; Gohl, K.; Jernas, P.; Wacker, L.

2017-12-01

In recent years several previously undiscovered grounding-zone wedges (GZWs) have been described within the Abbot-Cosgrove palaeo-ice stream trough on the easternmost Amundsen Sea Embayment shelf. These GZWs document both the Last Glacial Maximum (LGM; 26.5-19 cal. ka BP) grounding-line extent and the subsequent episodic retreat within this trough that neighbors the larger Pine Island-Thwaites trough to the west. Here we combine bathymetric, seismic, and geologic data showing that 1) the grounding line in Abbot Trough did not reach the continental shelf break at any time during the last glacial period, and 2) a prominent stacked GZW constructed from six individual wedges lying upon another was deposited 100 km upstream from the LGM grounding-line position. The available data allow for calculating volumes for most of these individual GZWs and for the entire stack. Sediment cores were recovered seawards from the outermost GZW in the trough, and from the individual wedges of the stacked GZW in order to define the LGM grounding-line extent, and provide minimum grounding-line retreat ages for the respective positions on the stacked GZW. We present implications of a grounded-ice free outer shelf throughout the last glacial period. Furthermore, we assess the significance of the grounding-line stillstand period recorded by the stacked GZW in Abbot Trough for the timing of post-LGM retreat of the West Antarctic Ice Sheet from the Amundsen Sea Embayment shelf.

Greenland's 20th Century retreat illuminated - great spatial variability with strong connections to subglacial topography and fjord bathymetry

Science.gov (United States)

Bjork, A. A.; Kjeldsen, K. K.; Boeckel, M. V.; Korsgaard, N. J.; Fenty, I. G.; Khan, S. A.; Mouginot, J.; Morlighem, M.; Rignot, E. J.; Dowdeswell, J. A.; Kjaer, K. H.

2017-12-01

Mass loss acceleration from the Greenland Ice Sheet is a dominant contributor in recent global sea-level rise, and has been for several decades. While ice sheet wide mass loss has recently been documented from the end of the Little Ice Age (c. 1900 CE) to the 1980s, the detailed changes during this period remain poorly known. In this study, we map glacier margins of Greenland's 310 largest outlet glaciers in order to get the full picture of the 20th Century mass loss. We take advantage of the rich history of aerial photography over Greenland and combine photos from archives in Denmark, Norway, United Kingdom, and United States. We supplement the historical aerial photographs with declassified US spy satellite imagery and recent satellite imagery to document glacial retreat and advance on a decadal scale. With recent advances in bathymetry mapping and subglacial topography mapping, we are able to show that spatial differences in retreat throughout the last 100 years are largely controlled by the underlying topography. Our study further highlights hotspots of past rapid mass loss in Greenland, and discusses implications for periods of regional stability and advance.

Cohort Trends in Premarital First Births: What Role for the Retreat From Marriage?

Science.gov (United States)

Wu, Lawrence L.; Shafer, Emily Fitzgibbons

2015-01-01

We examine cohort trends in premarital first births for U.S. women born between 1920 and 1964. The rise in premarital first births is often argued to be a consequence of the retreat from marriage, with later ages at first marriage resulting in more years of exposure to the risk of a premarital first birth. However, cohort trends in premarital first births may also reflect trends in premarital sexual activity, premarital conceptions, and how premarital conceptions are resolved. We decompose observed cohort trends in premarital first births into components reflecting cohort trends in (1) the age-specific risk of a premarital conception taken to term; (2) the age-specific risk of first marriages not preceded by such a conception, which will influence women’s years of exposure to the risk of a premarital conception; and (3) whether a premarital conception is resolved by entering a first marriage before the resulting first birth (a “shotgun marriage”). For women born between 1920–1924 and 1945–1949, increases in premarital first births were primarily attributable to increases in premarital conceptions. For women born between 1945–1949 and 1960–1964, increases in premarital first births were primarily attributable to declines in responding to premarital conceptions by marrying before the birth. Trends in premarital first births were affected only modestly by the retreat from marriages not preceded by conceptions—a finding that holds for both whites and blacks. These results cast doubt on hypotheses concerning “marriageable” men and instead suggest that increases in premarital first births resulted initially from increases in premarital sex and then later from decreases in responding to a conception by marrying before a first birth. PMID:24072609

The 20th century retreat of ice caps in Iceland derived from airborne SAR

DEFF Research Database (Denmark)

Magnússon, Eyjólfur; Björnsson, Helgi; Dall, Jørgen

2005-01-01

with the Danish airborne EMISAR radar system. Polarimetric and interferometric SAR data reveal the margins of the present ice caps as well as a series of terminal moraines in the fore field. These moraines date back to the maximum Neoglacial extent at the end of the 19th century and the outermost allow...... of the surges in W-Vatnajokull in the 20th century are observed in the SAR data including the most recent surges in the 1990s. Interestingly no push moraines were observed in front of the surge advance, but the moraines appear when the glaciers start retreating. We estimate that the collective decrease...

Nitrogen-controlled intra- and interspecific competition between Populus purdomii and Salix rehderiana drive primary succession in the Gongga Mountain glacier retreat area.

Science.gov (United States)

Song, Mengya; Yu, Lei; Jiang, Yonglei; Lei, Yanbao; Korpelainen, Helena; Niinemets, Ülo; Li, Chunyang

2017-06-01

In this study, intra- and interspecific competition were investigated in early successional Salix rehderiana Schneider and later-appearing Populus purdomii Rehder under non-fertilized (control) and nitrogen (N)-fertilized conditions in the Hailuogou glacier retreat area. Our aim was to discover whether N is a key factor in plant-plant competition and whether N drives the primary succession process in a glacier retreat area. We analyzed differences in responses to intra- and interspecific competition and N fertilization between P. purdomii and S. rehderiana, including parameters such as biomass accumulation, nutrient absorption, non-structural carbohydrates, photosynthetic capacity, hydrolysable amino acids and leaf ultrastructure. In the control treatments, S. rehderiana individuals subjected to interspecific competition benefited from the presence of P. purdomii plants, as indicated by higher levels of biomass accumulation, photosynthetic capacity, N absorption, amino acid contents and photosynthetic N-use efficiency. However, in the N-fertilized treatments, P. purdomii individuals exposed to interspecific competition benefited from the presence of S. rehderiana plants, as shown by a higher growth rate, enhanced carbon gain capacity, greater amino acid contents, and elevated water-use efficiency, whereas the growth of S. rehderiana was significantly reduced. Our results demonstrate that N plays a pivotal role in determining the asymmetric competition pattern among Salicaceae species during primary succession. We argue that the interactive effects of plant-plant competition and N availability are key mechanisms that drive primary succession in the Gongga Mountain glacier retreat area. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

CO{sub 2} and N{sub 2}O emissions in a soil chronosequence at a glacier retreat zone in Maritime Antarctica

Energy Technology Data Exchange (ETDEWEB)

Thomazini, A., E-mail: andre.thz@gmail.com [Department of Plant Production, Federal University of Espírito Santo, 29500-000 Alegre, Espírito Santo (Brazil); Mendonça, E.S., E-mail: eduardo.mendonca@ufes.br [Department of Plant Production, Federal University of Espírito Santo, 29500-000 Alegre, Espírito Santo (Brazil); Teixeira, D.B., E-mail: daniel.dbt@hotmail.com [FCAV/UNESP, Via de Acesso, Prof. Paulo Donato Castellane s/n, 14884-900 Jaboticabal, SP (Brazil); Almeida, I.C.C., E-mail: ivancarreiro@yahoo.com.br [Instituto Federal do Norte de Minas Gerais, Fazenda São Geraldo, s/n km. 06, 39480-000 Januária, Minas Gerais (Brazil); La Scala, N., E-mail: lascala@fcav.unesp.br [FCAV/UNESP, Via de Acesso, Prof. Paulo Donato Castellane s/n, 14884-900 Jaboticabal, SP (Brazil); Canellas, L.P., E-mail: lucianocanellas@gmail.com [UENF — Universidade Estadual do Norte Fluminense Darcy Ribeiro, Núcleo de Desenvolvimento de Insumos Biológicos para a Agricultura (NUDIBA), Av. Alberto Lamego, 2000, Campos dos Goytacazes 28013-602, Rio de Janeiro (Brazil); Spokas, K.A., E-mail: kurt.Spokas@ars.usda.gov [USDA-ARS, Soil and Water Management Unit, University of Minnesota — St. Paul, MN 55108 (United States); Milori, D.M.B.P., E-mail: debora.milori@embrapa.br [Embrapa Instrumentation Brazilian Agricultural Research Corporation, São Carlos, SP (Brazil); Turbay, C.V.G., E-mail: cturbay@gmail.com [Department of Geology, Federal University of Espírito Santo, 29500-000 Alegre, Espírito Santo (Brazil); and others

2015-07-15

Studies of C cycle alterations are extremely important to identify changes due to climate change, especially in the polar ecosystem. The objectives of this study were to (i) examine patterns of soil CO{sub 2}-C and N{sub 2}O-N emissions, and (ii) evaluate the quantity and quality of soil organic matter across a glacier retreat chronosequence in the Maritime Antarctica. Field measurements were carried out during January and February 2010 (summer season) along a retreating zone of the White Eagle Glacier, at King George Island, Maritime Antarctica. Soil samples (0–10 cm) were collected along a 500-m transect at regular intervals to determine changes in soil organic matter. Field CO{sub 2}-C emission measurements and soil temperature were carried out at regular intervals. In addition, greenhouse gas production potentials were assessed through 100 days laboratory incubations. Soils exposed for a longer time tended to have greater concentrations of soluble salts and possess sandier textures. Total organic C (3.59 g kg{sup −1}), total N (2.31 g kg{sup −1}) and labile C (1.83 g kg{sup −1}) tended to be lower near the glacier front compared with sites away from it, which is correlated with decreasing degree of humification of the soil organic matter with exposure time. Soil CO{sub 2}-C emissions tended to increase with distance from the glacier front. On average, the presence of vegetation increased CO{sub 2}-C emissions by 440%, or the equivalent of 0.633 g of CO{sub 2}-C m{sup −2} h{sup −1}. Results suggest that newly exposed landsurfaces undergo soil formation with increasing labile C input from vegetation, accompanied by increasing soil CO{sub 2}-C emissions. Despite the importance of exposure time on CO{sub 2}-C production and emissions, there was no similar trend in soil N{sub 2}O-N production potentials as a function of glacial retreat. For N{sub 2}O, instead, the maximum production occurred in sites with the first stages of vegetation growth

Three-dimensional evaluation of effectiveness of hand and rotary instrumentation for retreatment of canals filled with different materials.

Science.gov (United States)

Hammad, Mohammad; Qualtrough, Alison; Silikas, Nick

2008-11-01

The aim of this study was to measure the remaining filling volume of different obturation materials from root-filled extracted teeth by using 2 removal techniques. Eighty single-rooted teeth were collected and decoronated, and the root canal was prepared by using the ProTaper nickel-titanium rotary files. The teeth were randomly allocated into 4 groups, and each group was obturated by using a different material. Group 1 was filled with gutta-percha and TubliSeal sealer, group 2 was filled with EndoRez points and EndoRez sealer, group 3 was filled with RealSeal points and RealSeal sealer, and Group 4 was filled with a gutta-percha point and GuttaFlow sealer. Teeth were scanned with a micro-computed tomography scan, and then root fillings were removed by using ProTaper retreatment files or hand K-files. Teeth were scanned again, and volume measurements were carried out with micro-computed tomography software. Statistical analysis showed significant differences between the 2 removal techniques for gutta-percha and for both techniques between gutta-percha and the other groups. The present study showed that all tested filling materials were not completely removed during retreatment by using hand or rotary files. Gutta-percha was more efficiently removed by using hand K-files.

Sediment contribution from coastal-cliff erosion into the Nile's littoral cell and its significance to cliff-retreat mitigation efforts

Science.gov (United States)

Katz, Oded; Mushkin, Amit; Crouvi, Onn; Alter, Samuel; Shemesh, Ran

2017-04-01

In 2013 the government of Israel initiated a national mitigation program aimed to prevent further collapse and retreat of the country's coastal cliffs, which occur along the northern termination of the Niles's littoral cell (NLC) in the eastern Mediterranean. The goals of this large-scale program are to protect infrastructure and property proximal to the cliff and to conduct long-term maintenance and monitoring of this highly dynamic and sensitive land-sea interface that spans 40 km of Israel's coast line. Here, we examine the possible impact of proposed cliff retreat mitigation efforts on long-shore sediment transport (LST) and coastal dynamics in the region. We used airborne LiDAR spanning a 9-year period between 2006 and 2015 to quantify the annual contribution of sediment eroded from a 20-km-long segment of Israel's coastal cliffs into the NLC. Our measurements reveal 282±85*103 m3 of sediment eroded from the cliff and delivered into the NLC during the studied period. Considering our study area comprises 50% of Israel's sea cliffs we infer an average contribution rate of 30,000-60,000 m^3/yr of cliff-derived sediment into the NLC prior to the planned broad-scale implementation of cliff-retreat mitigation measures. Previous studies report an average net LST flux of 80,000 - 90,000 m3 that reaches the northern termination of the NLC at Haifa Bay annually. Thus, our results suggest that Israel's actively eroding coastal cliffs are primary contributors (40-80%) to the LST budget along the northern termination of the NLC. It therefore appears that successful implementation of the coastal-cliff protection program along Israel's coastline will result in a significant sand deficit, which may drive LST in this part of the NLC out of its 'background' state. In the likely case that the energy/currents driving LST do not change, a possible outcome of this sediment deficit could be increased beach erosion along Israel's coast line to make up for the lost volumes of cliff

Knickpoint retreat and transient bedrock channel morphology triggered by base-level fall in small bedrock river catchments: The case of the Isle of Jura, Scotland

Science.gov (United States)

Castillo, Miguel; Bishop, Paul; Jansen, John D.

2013-01-01

A sudden drop in river base-level can trigger a knickpoint that propagates throughout the fluvial network causing a transient state in the landscape. Knickpoint retreat has been confirmed in large fluvial settings (drainage areas > 100 km2) and field data suggest that the same applies to the case of small bedrock river catchments (drainage areas UK), where rivers incise into dipping quartzite. The mapping of raised beach deposits and strath terraces, and the analysis of stream long profiles, were used to identify knickpoints that had been triggered by base-level fall. Our results indicate that the distance of knickpoint retreat scales to the drainage area in a power law function irrespective of structural setting. On the other hand, local channel slope and basin size influence the vertical distribution of knickpoints. As well, at low drainage areas (~ 4 km2) rivers are unable to absorb the full amount of base-level fall and channel reach morphology downstream of the knickpoint tends towards convexity. The results obtained here confirm that knickpoint retreat is mostly controlled by stream discharge, as has been observed for other transient landscapes. Local controls, reflecting basin size and channel slope, have an effect on the vertical distribution of knickpoints; such controls are also related to the ability of rivers to absorb the base-level fall.

Peptide receptor radionuclide therapy (PRRT): clinical significance of re-treatment?

Energy Technology Data Exchange (ETDEWEB)

Virgolini, Irene [Medical University Innsbruck, Department of Nuclear Medicine, Innsbruck (Austria); Collaboration: The Innsbruck Team

2015-12-15

PRRT appears to be the most effective therapeutic option in the management of inoperable or metastasized NET patients with limited side effects if dose limits are respected. In patients with relapse after a first treatment period with {sup 90}Y-DOTATOC, multiple re-treatment cycles with {sup 177}Lu-DOTATATE are feasible, safe and efficacious. Quantitative imaging by dosimetry adds to formulate personalized and evidence-based treatment protocols. However, despite the large body of evidence regarding efficacy and safety of PRRT, the absence of prospective randomized controlled trials questions the utility of PRRT in the community. Furthermore, the growing number of pharmacological or liver-directed therapeutic options competes with the confusion based on the variety of somatostatin analogues to determine the optimal choice and sequencing of PRRT in the individual patient. However, the efficacy of PRRT should not be questioned rather than it should be explored as to when PRRT might be optimally applied in the sequence of available therapy modalities. The results of the present study by the Italian group [5] emphasizes that radiopharmaceuticals are still underused. Despite the huge potential of PRRT the non-availability of PRRT in many countries still limits its widespread use. After acquiring the exclusive rights for {sup 177}Lu-DOTATATE with granted orphan designation, the company Advanced Accelerator Applications (AAA) is currently running a phase III study comparing treatment with {sup 177}Lu-DOTATATE to Octreotide LAR in patients with inoperable, progressive, somatostatin receptor-positive, midgut carcinoid tumours with the aim of registering the radiopharmaceutical under the commercial name of Lutathera. Together with orphan designation also to other somatostatin-based radiopharmaceuticals, such as {sup 90}Y-DOTATOC, {sup 177}Lu-DOTATOC and the {sup 68}Ga-labelled somatostatin antagonist OPS202, these developments promote the advancement of PRRT and PET imaging

Successful retreatment with grazoprevir and elbasvir for patients infected with hepatitis C virus genotype 1b, who discontinued prior treatment with NS5A inhibitor-including regimens due to adverse events.

Science.gov (United States)

Kanda, Tatsuo; Yasui, Shin; Nakamura, Masato; Nakamoto, Shingo; Takahashi, Koji; Wu, Shuang; Sasaki, Reina; Haga, Yuki; Ogasawara, Sadahisa; Saito, Tomoko; Kobayashi, Kazufumi; Kiyono, Soichiro; Ooka, Yoshihiko; Suzuki, Eiichiro; Chiba, Tetsuhiro; Maruyama, Hitoshi; Moriyama, Mitsuhiko; Kato, Naoya

2018-03-23

Sustained virologic response (SVR) by interferon and interferon-free treatment can results in the reduction of advanced liver fibrosis and the occurrence of hepatocellular carcinoma in patients infected with hepatitis C virus (HCV). Recent interferon-free treatment for HCV shortens the duration of treatment and leads to higher SVR rates, without any serious adverse events. However, it is important to retreat patients who have had treatment-failure with HCV non-structural protein 5A (NS5A) inhibitor-including regimens. Combination of sofosbuvir and ledipasvir only leads to approximately 100% SVR rates in HCV genotype (GT1b), NS5A inhibitor-naïve patients in Japan. This combination is not an indication for severe renal disease or heart disease, and these patients should be treated or retreated with a different regimen. Retreatment with HCV non-structural protein 3/4A inhibitor, grazoprevir, and HCV NS5A inhibitor, elbasvir, successfully eradicated HCV RNA in three patients with HCV genotype 1b infection who discontinued prior interferon-free treatments including HCV NS5A inhibitors due to adverse events within 2 weeks. Retreatment with the 12-week combination regimen of grazoprevir and elbasvir is effective for HCV GT1b patients who discontinue the HCV NS5A inhibitor-including regimens within 2 weeks. The treatment response may be related to the short duration of initial treatment, which did not produce treatment-emergent RASs.

Influence of Cone-beam Computed Tomography on Endodontic Retreatment Strategies among General Dental Practitioners and Endodontists.

Science.gov (United States)

Rodríguez, Gustavo; Patel, Shanon; Durán-Sindreu, Fernando; Roig, Miguel; Abella, Francesc

2017-09-01

Treatment options for endodontic failure include nonsurgical or surgical endodontic retreatment, intentional replantation, and extraction with or without replacement of the tooth. The aim of the present study was to determine the impact of cone-beam computed tomographic (CBCT) imaging on clinical decision making among general dental practitioners and endodontists after failed root canal treatment. A second objective was to assess the self-reported level of difficulty in making a treatment choice before and after viewing a preoperative CBCT scan. Eight patients with endodontically treated teeth diagnosed as symptomatic apical periodontitis, acute apical abscess, or chronic apical abscess were selected. In the first session, the examiners were given the details of each case, including any relevant radiographs, and were asked to choose 1 of the proposed treatment alternatives and assess the difficulty of making a decision. One month later, the examiners reviewed randomly the same 8 cases with the additional information from the CBCT data. The examiners altered their treatment plan after viewing the CBCT scan in 49.8% of the cases. A significant difference in the treatment plan between the 2 imaging modalities was recorded for endodontists and general practitioners (P < .05). After CBCT evaluation, neither group altered their self-reported level of difficulty when choosing a treatment plan (P = .0524). The extraction option rose significantly to 20% after viewing the CBCT scan (P < .05). CBCT imaging directly influences endodontic retreatment strategies among general dental practitioners and endodontists. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

GIS- and field based mapping of geomorphological changes in a glacier retreat area: A case study from the Kromer valley, Silvretta Alps (Austria)

Science.gov (United States)

Guttmann, Markus; Pöppl, Ronald

2017-04-01

Global warming results in an ongoing retreat of Alpine glaciers, leaving behind large amounts of easily erodible sediments. As a consequence processes like rockfalls, landslides and debris flows as well as fluvial processes occur more frequently in pro- and paraglacial areas, often involving catastrophic consequences for humans and infrastructure in the affected valleys. The main objective of the presented work was to map and spatially quantify glacier retreat and geomorphological changes in the Kromer valley, Silvretta Alps (Austria) by applying GIS- and field-based geomorphological mapping. In total six geomorphological maps (1950s, 1970s, 2001, 2006, 2012, and 2016) were produced and analyzed in the light of the study aim. First results have shown a significant decrease of total glaciated area from 96 ha to 53 ha which was accompanied by increased proglacial geomorphic activity (i.e. fluvial processes, rockfalls, debris flows, shallow landslides) in the last 15 years. More detailed results will be presented at the EGU General Assembly 2017.

Asian monsoons and aridification response to Paleogene sea retreat and Neogene westerly shielding indicated by seasonality in Paratethys oysters

Science.gov (United States)

Bougeois, Laurie; Dupont-Nivet, Guillaume; de Rafélis, Marc; Tindall, Julia C.; Proust, Jean-Noël; Reichart, Gert-Jan; de Nooijer, Lennart J.; Guo, Zhaojie; Ormukov, Cholponbelk

2018-03-01

Asian climate patterns, characterised by highly seasonal monsoons and continentality, are thought to originate in the Eocene epoch (56 to 34 million years ago - Ma) in response to global climate, Tibetan Plateau uplift and the disappearance of the giant Proto-Paratethys sea formerly extending over Eurasia. The influence of this sea on Asian climate has hitherto not been constrained by proxy records despite being recognised as a major driver by climate models. We report here strongly seasonal records preserved in annual lamina of Eocene oysters from the Proto-Paratethys with sedimentological and numerical data showing that monsoons were not dampened by the sea and that aridification was modulated by westerly moisture sourced from the sea. Hot and arid summers despite the presence of the sea suggest a strong anticyclonic zone at Central Asian latitudes and an orographic effect from the emerging Tibetan Plateau. Westerly moisture precipitating during cold and wetter winters appear to have decreased in two steps. First in response to the late Eocene (34-37 Ma) sea retreat; second by the orogeny of the Tian Shan and Pamir ranges shielding the westerlies after 25 Ma. Paleogene sea retreat and Neogene westerly shielding thus provide two successive mechanisms forcing coeval Asian desertification and biotic crises.

Paludification and forest retreat in northern oceanic environments.

Science.gov (United States)

Crawford, R M M; Jeffree, C E; Rees, W G

2003-01-01

Examination of temperature variations over the past century for Europe and the Arctic from northern Norway to Siberia suggests that variations in the North Atlantic Oscillation are associated with an increase in oceanicity in certain maritime regions. A southward depression of the tree line in favour of wet heaths, bogs and wetland tundra communities is also observed in northern oceanic environments. The physiological basis for this change in ecological succession from forest to bog is discussed in relation to the long-term effects of flooding on tree survival. The heightened values currently detected in the North Atlantic Oscillation Index, together with rising winter temperatures, and increased rainfall in many areas in northern Europe, presents an increasing risk of paludification with adverse consequences for forest regeneration, particularly in areas with oceanic climates. Climatic warming in oceanic areas may increase the area covered by bogs and, contrary to general expectations, lead to a retreat rather than an advance in the northern limit of the boreal forest. High water-table levels are not automatically detrimental to forest survival as can be seen in swamp, bottom land and mangrove forests. Consequently, the inhibitory effects of flooding on tree survival and regeneration in northern regions should not be uncritically accepted as merely due to high water levels. Evidence is discussed which suggests that physiological and ecological factors may interact to inhibit forest regeneration in habitats where there is a risk of prolonged winter-flooding combined with warmer winters and cool moist summers.

Effectiveness of a calcium hydroxide and chlorhexidine digluconate mixture as disinfectant during retreatment of failed endodontic cases.

Science.gov (United States)

Zerella, Joseph A; Fouad, Ashraf F; Spångberg, Larz S W

2005-12-01

The purpose of this in vivo investigation is to compare the effect of a slurry of Ca(OH)2 mixed in aqueous 2% chlorhexidine (CHX) versus aqueous Ca(OH)2 slurry alone on the disinfection of the pulp space of failed root-filled teeth during endodontic retreatment. Forty single-rooted previously root-filled teeth with associated periradicular lesions were included. The teeth were nonsurgically retreated and medicated over 3 treatment visits with 7-10-day intervals with either Ca(OH)2 in water or Ca(OH)2 in 2% aqueous CHX. Root canal cultures were collected in fluid thioglycollate, and bacterial growth was assessed by turbidity daily for 1 week, then weekly for an additional 3 weeks. The presence of enterococci in the root canals at the initial treatment session was determined. Of the total sample population, 12 of 40 (30%) were positive for bacteria before root filling. The control medication disinfected 12 of 20 (60%) teeth including 2 of 4 teeth originally diagnosed with enterococci. The experimental medication resulted in disinfected 16 of 20 (80%) teeth at the beginning of the third appointment. None of the teeth originally containing enterococci showed remaining growth. This difference between the overall positive cultures was not statistically significant (P > .05). Canal dressing with a mixture of 2% CHX and Ca(OH)2 slurry is as efficacious as aqueous Ca(OH)2 on the disinfection of failed root-filled teeth.

How do how internal and external processes affect the behaviors of coupled marsh mudflat systems; infill, stabilize, retreat, or drown?

Science.gov (United States)

Carr, J. A.; Mariotti, G.; Wiberg, P.; Fagherazzi, S.; McGlathery, K.

2013-12-01

Intertidal coastal environments are prone to changes induced by sea level rise, increases in storminess, and anthropogenic disturbances. It is unclear how changes in external drivers may affect the dynamics of low energy coastal environments because their response is non-linear, and characterized by many thresholds and discontinuities. As such, process-based modeling of the ecogeomorphic processes underlying the dynamics of these ecosystems is useful, not only to predict their change through time, but also to generate new hypotheses and research questions. Here, a three-point dynamic model was developed to investigate how internal and external processes affect the behavior of coupled marsh mudflat systems. The model directly incorporates ecogeomorphological feedbacks between wind waves, salt marsh vegetation, allochthonous sediment loading, tidal flat vegetation and sea level rise. The model was applied to examine potential trajectories of salt marshes on the Eastern seaboard of the United States, including those in the Plum Island Ecosystems (PIE), Virginia Coast Reserve (VCR) and Georgia Coastal Ecosystems (GCE) long term ecological research (LTER) sites. While these sites are undergoing similar rates of relative sea level rise (RSLR), they have distinct differences in site specific environmental drivers including tides, wind waves, allochthonous sediment supply and the presence or absence of seagrass. These differences lead to the emergence of altered behaviors in the coupled salt marsh-tidal flat system. For marsh systems without seagrass or significant riverine sediment supply, conditions similar to those at PIE, results indicated that horizontal and vertical marsh evolution respond in opposing ways to wave induced processes. Marsh horizontal retreat is triggered by large mudflats and strong winds, whereas small mudflats and weak winds reduce the sediment supply to the salt marsh, decreasing its capability to keep pace with sea level rise. Marsh expansion and

Predicting Land-Ice Retreat and Sea-Level Rise with the Community Earth System Model

Energy Technology Data Exchange (ETDEWEB)

Lipscomb, William [Los Alamos National Laboratory

2012-06-19

Coastal stakeholders need defensible predictions of 21st century sea-level rise (SLR). IPCC assessments suggest 21st century SLR of {approx}0.5 m under aggressive emission scenarios. Semi-empirical models project SLR of {approx}1 m or more by 2100. Although some sea-level contributions are fairly well constrained by models, others are highly uncertain. Recent studies suggest a potential large contribution ({approx}0.5 m/century) from the marine-based West Antarctic Ice Sheet, linked to changes in Southern Ocean wind stress. To assess the likelihood of fast retreat of marine ice sheets, we need coupled ice-sheet/ocean models that do not yet exist (but are well under way). CESM is uniquely positioned to provide integrated, physics based sea-level predictions.

Impacts of Aerosols on the Retreat of the Sierra Nevada Glaciers in California

Science.gov (United States)

El-Askary, H. M.; Li, J.; Ta, T. N.; Jong, A.; Zhang, X.

2015-12-01

Natural dust aerosol is an active component of the climate system and plays multiple roles in physical climate and bio-geo-chemical exchanges between the atmosphere, land surface and ocean. Aerosol deposition on snow is amongst the different causes of glacier retreat around the world as well as the reduction of snow albedo. We have observed a long range transport of dust and pollution aerosols from China to the U.S. In this paper we compared summer and winter seasons glacier changes between 2000 and 2013, and how the dust aerosol change over this 13 years. Multiple images, acquired from Landsat-5 TM, Landsat-7 ETM+ and Landsat-8 OLI were used in the study. The change detection analysis was employed to identify the glacier changes for two seasons. The results suggest that the glacier decreased dramatically over 13 years in both seasons.

Glacitectonic deformation around the retreating margin of the last Irish ice sheet

Science.gov (United States)

Knight, J.

2008-12-01

Evidence for ice-marginal glacitectonic shunting and deformation of bedrock slabs is described from three sites around the west coast of Ireland. These sites (Brandon Bay, County Kerry; Pigeon Point, County Mayo; Inishcrone, County Sligo) are all locations where the late Devensian ice margin retreated on land and was confined to within limestone bedrock embayments. At these sites, flat-lying bedrock slabs (bedrock slabs have been variously stacked, rotated, deformed into open folds, and brecciated. Separating the bedrock slabs is either a thin layer (bedrock that shows internal folding; or a thicker (bedrock fractures and bedding planes and away from the ice margin, and that bedrock slabs were moved in part by hydraulic lift as well as thrust-style ice-marginal tectonics. The presence of a mosaic of warm and frozen ice-bed patches, in combination with strong geologic control and meltwater generation from behind the ice margin, can help explain formation of these unusual bedrock slab features.

Comparison of efficiency of the retreatment procedure between Wave One Gold and Wave One systems by Micro-CT and confocal microscopy: an in vitro study.

Science.gov (United States)

Canali, Lyz Cristina Furquim; Duque, Jussaro Alves; Vivan, Rodrigo Ricci; Bramante, Clovis Monteiro; Só, Marcus Vinícius Reis; Duarte, Marco Antonio Hungaro

2018-04-19

To compare, by Micro-CT and confocal laser scanning microscopy (CLSM), the ability of the Wave One Gold and Wave One systems to remove filling material from mesial canals of mandibular molars, effective time spent; quantity of extruded material, and percentage of sealer in the dentinal tubules after retreatment and re-obturation procedures. Ten first mandibular molars (n = 20 mesial canals) were prepared and filled with gutta-percha and Endofill sealer mixed with Rhodamine B dye using the single cone technique. After 7 days, the canals were scanned using a high-definition micro-computer tomography with 19-mm voxel size and divided into two groups (n = 10) according to the system used in retreatment: group 1, Wave One (WO), and group 2, Wave One Gold (WG). After removing filling material with the primary file of each system, the WO 40/.08 and WG 35/.06 files were used. After using each file, a new scanning was performed and the residual filling material and extruded filling material were measured. The effective time spent to remove the canal filling was measured after each instrument. After retreatment, the teeth were re-obturated with gutta-percha and AH Plus sealer mixed with fluorescein dye using the single-cone technique. The roots were sectioned at 2, 4 and 6 mm and analysed by CLSM to measure the percentage of remaining sealer and the sealer of the new root canal filling. The data were statistically compared (P  0.05). When using WO 25, the operator spent significantly less effective time than when using WG 25 (P  0.05). Neither of the two systems removed all the filling material. The WG system presented similar ability in removing filling and extruded material in comparison with WO system. The effective time spent was shorter for WO 25 than for WG 25. Wave One Gold can be an alternative to perform retreatment considering that in comparison with Wave One, there was no difference in filling material removal capacity and extruded materials

Recent glacier retreat and lake formation in the Querecocha watershed, Cordillera Blanca, Peru

Science.gov (United States)

López Moreno, J.; Valero-Garces, B.; Revuelto, J.; Azorín-Molina, C.; Bazo, J.; Cochachin, A.; Fontaneda, S.; Mark, B. G.

2013-12-01

In the Andes, and specifically in the Peruvian mountains a marked decrease of the glaciated area has occurred since the end of the Little Ice Age, and it has been accelerated since the last decades of the 20th century. As a result of the glacier retreat new pro-glaciar lakes are originated, and often the area and volume of existing ones increases. The study of these newly-formed lakes and their recent evolution may provide a better understanding of the hydrological and geomorphological evolution of deglaciated areas, and a better evaluation of the risk of glacial lakes outburst floods (GLOFS). In this work, we use 26 annual Landsat Thematic Mapper images from 1975 to 2010 to determine changes of the glaciated surface, snow line elevation and lakes formation in the headwaters of the Querecocha watershed in Cordillera Blanca (Perú). We also present the information derived from 10 short sediment cores (up to 50 cm long) retrieved along several transects in Yanamarey Lake. Both data sets inform of the sediment yield and lake development in recently deglaciated environments of the Andes. Results demonstrate that only one third of the surface covered by ice in 1975 remained in 2010. In this period, snowline has shifted up more than 100 meters in elevation in both, Yanamarey North and South areas respectively. At the same time, new lakes have been formed very quickly in these deglaciated areas. Preliminary 137Cs dating of Yanamarey sediment core indicates that at least the top 50 cm of the lake sequence deposited after 1960. This is coherent with the Landsat image of 1975 that showed the current surface of the lake still covered by ice. The high sediment rate (> 1 cm/yr) in the lake demonstrates the very high sediment yield in these geomorphically active settings. The sediment cores are composed of cm-thick sequences defined by grain-size (silt-clay) common in proglacial lakes reflecting the variability of hydrological response associated to the glacier retreat in the

An in vivo study evaluating lesion sterilization and tissue repair 3 MIX-MP noninstrumentation endodontic treatment as an alternative to conventional endodontic retreatment

Directory of Open Access Journals (Sweden)

Vaishnavi Dasari

2016-01-01

Full Text Available Aim: To alleviate the patient's symptoms and promote periapical healing in teeth with failure of root canal treatment, without the removal of previous obturating material using lesion sterilization and tissue repair (LSTR 3 MIX-MP noninstrumentation endodontic treatment (NIET. Materials and Methods: Fifteen single-rooted teeth with a history of root canal treatment 1–2 years previously, requiring retreatment, with pain, sinus tract, swelling and periapical lesions, and having acceptable obturation were included in the study. The previous coronal restoration was removed, and a medication cavity was prepared for placement of 3MIX MP; this was followed by lining with Glass ionomer cement and a coronal restoration with composite resin. Results: At 8 weeks, all patients did not have either pain, tenderness on vertical percussion, pain on biting, or swelling (asymptomatic. Radiographically, the periapical lesions had reduced by 1 mm in five cases. In six patients, the lesion size remained unchanged. Conclusion: LSTR NIET is an excellent, inexpensive, less traumatic, and least time-consuming alternative to treat symptomatic teeth requiring endodontic retreatment.

Historical analysis and visualization of the retreat of Findelengletscher, Switzerland, 1859-2010

Science.gov (United States)

Rastner, P.; Joerg, P. C.; Huss, M.; Zemp, M.

2016-10-01

Since the end of the Little Ice Age around 1850, glaciers in Europe have strongly retreated. Thanks to early topographic surveys in Switzerland, accurate maps are available, which enable us to trace glacier changes back in time. The earliest map for all of Switzerland that is usable for a detailed analysis is the Dufour map from around 1850 with subsequent topographic maps on a 20 year interval. Despite the large public and scientific interest in glacier changes through time, this historic dataset has not yet been fully utilized for topographic change assessment or visualization of historic glacier extents. In this study, we use eleven historical topographic maps and more recent digital datasets for the region of Zermatt to analyze geometric changes (length, area and volume) of Findelengletscher as well as for creating animations of glacier evolution through time for use in public communication. All maps were georeferenced, the contour lines digitized, and digital elevation models (DEMs) created and co-registered. Additional digital data like the SRTM X-band DEM and high resolution laser scanning data were used to extend the analysis until 2010. Moreover, one independent DEM from aerial photogrammetry was used for comparison. During the period 1859-2010, Findelengletscher lost 3.5 km of its length (6.9 km in 2010), 4.42 ± 0.13 km2 of its area (15.05 ± 0.45 km2 in 2010) and 1.32 ± 0.52 km3 of its volume. The average rate of thickness loss is 0.45 ± 0.042 m yr- 1 for the 151 years period. Four periods with high thickness change from - 0.56 m ± 0.28 yr- 1 (1859-1881), - 0.40 ± 0.08 m yr- 1 (1937-1965), - 0.90 ± 0.31 m yr- 1 (1995-2000) and - 1.18 ± 0.02 m yr- 1 (2000-2005) have been identified. Small positive thickness changes were found for the periods 1890-1909 (+ 0.09 ± 0.46 m yr- 1) and 1988-1995 (+ 0.05 ± 0.24 m yr- 1). During its retreat with intermittent periods of advance, the glacier separated into three parts. The above changes are demonstrated

Impact of treatment and re-treatment with artemether-lumefantrine and artesunate-amodiaquine on selection of Plasmodium falciparum multidrug resistance gene-1 polymorphisms in the Democratic Republic of Congo and Uganda.

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Vito Baraka

Full Text Available The emergence of resistance against artemisinin combination treatment is a major concern for malaria control. ACTs are recommended as the rescue treatment, however, there is limited evidence as to whether treatment and re-treatment with ACTs select for drug-resistant P. falciparum parasites. Thus, the purpose of the present study is to investigate the impact of (re-treatment using artesunate-amodiaquine (ASAQ and artemether-lumefantrine (AL on the selection of P. falciparum multidrug resistance-1 (Pfmdr1 alleles in clinical settings.P. falciparum positive samples were collected from children aged 12-59 months in a clinical trial in DR Congo and Uganda. Pfmdr1 single nucleotide polymorphisms (SNPs analysis at codons N86Y, Y184F, and D1246Y were performed at baseline and post-treatment with either AL or ASAQ as a rescue treatment using nested PCR followed by restriction fragment length polymorphism (RFLP assays.The pre-treatment prevalence of Pfmdr1 N86 and D1246Y varied significantly between the sites, (p>0.001 and (p = 0.013, respectively. There was borderline significant directional selection for Pfmdr1 184F in recurrent malaria infections after treatment with AL in Uganda site (p = 0.05. Pfmdr1 NFD haplotype did not significantly change in post-treatment infections after re-treatment with either AL or ASAQ. Comparison between pre-treatment and post-treatment recurrences did not indicate directional selection of Pfmdr1 N86, D1246 alleles in the pre-RCT, RCT and post-RCT phases in both AL and ASAQ treatment arms. Pfmdr1 86Y was significantly associated with reduced risk of AL treatment failure (RR = 0.34, 95% CI:0.11-1.05, p = 0.04 while no evidence for D1246 allele (RR = 1.02; 95% CI: 0.42-2.47, p = 1.0. Survival estimates showed that the Pfmdr1 alleles had comparable mean-time to PCR-corrected recrudescence and new infections in both AL and ASAQ treatment arms.We found limited impact of (re-treatment with AL or ASAQ on selection for Pfmdr1

Predictors of Treatment Outcome for Retreatment Pulmonary Tuberculosis Cases among Tribal People of an Eastern India District: A Prospective Cohort Study

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Rajib Saha

2016-01-01

Full Text Available Objective. The study was conducted to assess the treatment outcome of different category retreatment cases with the aim of finding out the important predictors of unfavorable outcomes. Methodology. This hospital based prospective cohort study was conducted in three tuberculosis units (TUs of west Midnapore (a district of Eastern India, covering mostly the tribal populated areas. Patients who were registered for Category II antituberculosis treatment between 1st quarter of 2013 (Jan to Mar and 4th quarter of 2013 (Oct to Dec were considered as our study cohort and they were followed up till December 2014. The study was started with 177 patients but ultimately ended with 165 patients. Results. Unfavorable outcome was observed among 24.8% patients. Among them mostly 51.2% were defaulter, 22% were failure case, and 26.8% died during treatment. Patients, who were minority by religion, were found 4 times more vulnerable for unfavorable outcome. Unfavorable outcome was found 7 times more common among retreatment TB cases who remain sputum positive after completion of initiation phase of Category II treatment. Conclusion. Programmatic approach should be specified to address the minority by religion population and to reduce the load of sputum positive cases after completion of initiation phase treatment by tracking them.

Role of assesssment for retreatment with transarterial chemoembolization score in decision of retreatment with trans-arterial chemo-embolization sessions in patients with hepatocellular carcinoma

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Abbasi, A.H.; Abid, S.; Haq, T.U.; Awan, S.

2017-01-01

Background: The objective behind this study was to determine that Assessment for Re-treatment with Transarterial chemoembolization (ART) score is really applicable in patients with hepatocellular carcinoma. Methods: A cross sectional observational study was conducted on all patients with hepatocellular carcinoma of intermediate stage and undergone ≥2 Transarterial chemoembolization. ART score was assessed before and after each session of Transarterial chemoembolization. Multi-logistic regression analysis was performed to compare the final outcome of patients with ART score of ≥2.5 into groups with two and more than two Trans-arterial chemo-embolization sessions. Results: A total of 100 HCC patients were recruited for final analysis. Our study participants consisted of total 100 HCC patients. Mean Child Pugh score was 6.1±0.95. In our study, most of the study participants (n=63) had ART score of less than 1.5 as compared to ART score >2.5 (n=37). A significant proportion of patients with ART score of 2.5, p-value<0.001. Patients with ART score of more than 2.5 did not show any survival benefit after having 3rd or 4th Trans-arterial chemo-embolization session, p=0.47. Conclusions: Our study findings suggest that those HCC patients who receive multiple sessions of TACE with a low ART score have more favourable outcomes with increased survival rate. (author)

Attempts to retreat from a dead-ended long capillary by backward swimming in Paramecium

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Itsuki eKunita

2014-06-01

Full Text Available We have observed how the ciliate Paramecium attempts to retreat from the dead-end of a long capillary that is too narrow for turning. After many trial-and-error episodes of short-term backward swimming (SBS, which is the conventional avoidance behavior exhibited in free swimming when an obstacle is faced, long-term backward swimming (LBS that lasted five to ten times longer was developed. LBS may have a beneficial effect for complete withdrawal from the capillary space, although in our experiment it was impossible for the organism to do so due to the capillary length. In order to identify a physically possible mechanism for LBS, we propose model equations for the membrane potential of Hodgkin-Huxley type, which describe the control of ciliary movement. The physiological implications and physical mechanism of the development of LBS are discussed.

Knickpoint formation and landscape response following coastal cliff retreat at last-interglacial sea-level highstand: Kaua';i, Hawai';i (Invited)

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Lamb, M. P.; Mackey, B. H.; Farley, K. A.; Scheingross, J. S.

2013-12-01

The upstream propagation of knickpoints is an important mechanism for channel incision and communicates changes in climate, sea level and tectonics throughout a landscape. Here, we use cosmogenic 3He exposure dating to document the retreat rate of a waterfall in Ka'ula'ula Valley, Kaua';i, Hawai';i, an often-used site for knickpoint-erosion modeling. Exposure ages of terraces are oldest near the coast (120 ka) and systematically decrease with upstream distance towards the waterfall (waterfall migrated 4 km over the past 120 ka at an average rate of 33 mm/yr. Upstream of the knickpoint, cosmogenic nuclide concentrations in channel are approximately uniform and indicate steady-state vertical erosion at a rate of ~0.03 mm/yr. Field observations and topographic analyses suggest that waterfall retreat is dominated by block toppling, with sediment transport below the waterfall actively occurring by debris flows. Knickpoint initiation was previously attributed to a submarine landslide ca. 4 Ma; however, our dating results, bathymetric analysis, and landscape-evolution modeling support knickpoint generation by wave-induced seacliff erosion during the last interglacial sea-level high stand. We illustrate that knickpoint generation during sea-level high stands, as opposed to the typical case of sea-level fall, is an important relief-generating mechanism on steep coasts with stable or subsiding coasts, and likely drives transient pulses of significant source-to-sink sediment flux.

Sedimentation and erosion in Lake Diefenbaker, Canada: solutions for shoreline retreat monitoring.

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Sadeghian, Amir; de Boer, Dirk; Lindenschmidt, Karl-Erich

2017-09-15

This study looks into sedimentation and erosion rates in Lake Diefenbaker, a prairie reservoir, in Saskatchewan, Canada, which has been in operation since 1968. First, we looked at the historical data in all different formats over the last 70 years, which includes data from more than 20 years before the formation of the lake. The field observations indicate high rates of shoreline erosion, especially in the upstream portion as a potential region for shoreline retreat. Because of the great importance of this waterbody to the province, monitoring sedimentation and erosion rates is necessary for maintaining the quality of water especially after severe floods which are more common due to climate change effects. Second, we used Google Maps Elevation API, a new tool from Google that provides elevation data for cross sections drawn between two points, by drawing 24 cross sections in the upstream area extending 250 m from each bank. This feature from Google can be used as an easy and fast monitoring tool, is free of charge, and provides excellent control capabilities for monitoring changes in cross-sectional profiles.

One-visit endodontic retreatment of combined external/internal root resorption using a calcium-enriched mixture.

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Asgary, Saeed; Ahmadyar, Maryam

2012-01-01

Combined external and internal root resorption (ERR/IRR) is a rare endodontic disease that leads to alteration of the root canal anatomy. This report describes the management of an endodontically failed molar that was severely affected by ERR/IRR. Radiographic examination demonstrated inadequate obturation of the root canals associated with ERR/IRR and a large periradicular lesion. During nonsurgical endodontic retreatment, the root canals were subjected to conventional chemomechanical debridement. In the same session, the entire distal root canal was obturated using a calcium-enriched mixture (CEM) cement, and the mesial canals were obturated with gutta-percha/sealer. The clinical findings and follow-up radiographs indicated favorable treatment outcomes after 12 months. One-visit application of CEM cement could be a successful approach for the management of combined ERR/IRR.

Knickpoint formation, rapid propagation, and landscape response following coastal cliff retreat at last-interglacial sea-level highstand: Kaua'i, Hawai'i

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Lamb, Michael; Mackey, Ben; Scheingross, Joel; Farley, Ken

2013-04-01

The propagation of knickpoints through a landscape is recognized as a highly efficient mechanism of channel incision, and exerts a first-order control in communicating changes in base level throughout a landscape. However, few settings allow reconstruction of the long-term rate of knickpoint retreat. Here, we use cosmogenic 3He exposure dating of olivine within basalt to document the retreat rate of a waterfall in Ka'ula'ula Valley, a small catchment on the Na Pali coast of Kaua'i, Hawai'i. We constrained the exposure age of 18 features (in-channel boulders, stable boulders on terraces, and in-channel bedrock) along the length of the channel that allow us to discriminate between models of knickpoint propagation. Cosmogenic exposure ages are oldest near the coast (120 ka) and systematically decrease with upstream distance towards the waterfall (waterfall has migrated 4 km up valley over the past 120 ka at an average rate of 33 mm/yr. Steady-state vertical erosion appears to dominate upstream of the waterfall, where the channel has incised ~100 m into the original surface of the shield volcano. Our results indicate the lateral rate of knickpoint retreat exceeds rates of vertical channel incision by three orders of magnitude, and that knickpoints may be the primary driver of relief generation in Hawaiian catchments. Submarine landslides have been proposed as the cause of knickpoints in Kaua'i streams; however, the bathymetry off the northwest Kaua'i coast lacks evidence for large submarine flank collapse. Alternatively, we propose substantial cliff erosion during the last interglacial sea-level highstand generated a waterfall at the coast, which has subsequently propagated inland. Superimposing Kaua'i's subsidence history and Pleistocene sea level fluctuations indicate that the only time waves could have eroded cliffs at Ka'ula'ula Valley's entrance over the past 1.5 Ma was during the last interglacial, ~130-120 ka. Knickpoint generation during sea level high stands

Late Burdigalian sea retreat from the North Alpine Foreland Basin: new magnetostratigraphic age constraints

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Sant, K.; Kirscher, U.; Reichenbacher, B.; Pippèrr, M.; Jung, D.; Doppler, G.; Krijgsman, W.

2017-05-01

Accurate reconstruction of the final sea retreat from the North Alpine Foreland Basin (NAFB) during the Burdigalian (Early Miocene) is hampered by a lack of reliable age constraints. In this high resolution magnetostratigraphic study we try to solve a significant age bias for the onset of the Upper Freshwater Molasse (OSM) deposition in the neighboring S-German and Swiss Molasse Basins. We measured > 550 samples from eleven drill cores covering the transition from marine to brackish to freshwater environments in the S-German Molasse Basin. Based on combined bio-, litho- and magnetostratigraphic constraints, the composite magnetostratigraphic pattern of these cores provides two reasonable age correlation options (model 1 and 2). In model 1, the base of the brackish succession lies within Chron C5Cr ( 16.7-17.2 Ma), and the onset of OSM deposition has an age of 16.5 Ma. Correlation model 2 suggests the transition to brackish conditions to be within C5Dr.1r ( 17.7-17.5 Ma), and yields an age around 16.7 Ma for the shift to the OSM. Most importantly, both models confirm a much younger age for the OSM base in the study area than previously suggested. Our results demonstrate a possible coincidence of the last transgressive phase (Kirchberg Fm) with the Miocene Climatic Optimum (model 1), or with the onset of this global warming event (model 2). In contrast, the final retreat of the sea from the study area is apparently not controlled by climate change. Supplementary material B. Profiles of the eleven studied drill cores including lithologies, all magnetostratigraphic data (inclinations), interpreted polarity pattern (this study and Reichenbacher et al., 2013) and magnetic susceptibility (this study). Legend for graphs on page 1. Samples without a stable direction above 200 °C or 20 mT are depicted as +-signs and plotted at 0° inclination. The interpreted normal (black), reversed (white) and uncertain (grey) polarity zones in the polarity columns are based on at least

Timing of Glacial Lake Missoula Outburst Floods and the southwestern Cordilleran Ice Sheet retreat.

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Hendy, I. L.; Bervid, H. D.; Carlson, A. E.

2017-12-01

Glacial Lake Missoula formed when the Purcell Trench Lobe dammed the Clark Fork River in Montana and catastrophically collapsed repeatedly through the last glacial period as the southern Cordilleran Ice Sheet advanced and retreated. A well-dated 50-kyr jumbo piston core MD02-2496 (48.97˚ N, 127.04˚ W, water depth of 1243 m) collected from the continental slope 75 km off Vancouver Island contains evidence of these floods. The in-situ bulk elemental composition of the 35-m core was determined at 1 mm intervals using an ITRAX X-ray Fluorescence (XRF) Core Scanner (Cox Analytical Instruments) at the Sediment Geochemistry Lab of the College of Earth, Ocean, and Atmospheric Sciences at Oregon State University. With 40 mixed planktonic foraminifera and bulk organic carbon 14C ages, the core provides a high-resolution resolution record of glaciomarine sedimentation during deglaciation. A series of >81 layers of fine-grained sediments with ancient (K/Ar ages of 300 Ma and eNd of -8) shale-like (high Rb counts) composition can be found between 19.6 and 9.2 m below coretop. These layers are interspersed by coarser grained, young (K/Ar ages of 100 Ma and eNd of -3) sediments containing ice-rafted debris (IRD). The composition and age of the layers indicates the sediments originated in Glacial Lake Missoula and were transported by ocean currents 250 miles north along the west coast of North America. The flood layers begin at 19.5 ka with five thin (5 cm thick) appear after 19.3 ka. At 17.1 ka, IRD concentrations increase from 50 grains g-1 from 16.5-16.35 ka, except in flood layers, as the Juan de Fuca Strait deglaciated. Another 16 flood layers occur from 16.3-15.65 ka; however, the base and top of these layers are diffuse rather than abrupt like earlier flood layers suggesting enhanced mixing between flood and melt waters. The final flood layers from 14.9-14.5 ka are thin (Lake Missoula flood sedimentation changed during the advance and retreat of the Cordilleran Ice Sheet.

Retreatment of a mandibular second premolar with two canals in two roots

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Chiara Fossati

2018-06-01

Full Text Available Aim: To present a case of retreatment in mandibular second premolar with two canals in two roots. Summary: Locating, cleaning and shaping the entire root canal system may represent a difficult challenge particularly in mandibular premolars, because of their complex canal systems.For this reason mandibular premolars are often considered the most difficult of all teeth on which to perform successful endodontic treatment. Vertucci stated that the second premolar has one root canal at the apex in 97.5% of the teeth studied and two canals in only 2.5%.1 The following case report describes the diagnosis and retreatment of a second premolar with two canal in two roots.Key learning points: (1 The major cause of failure in root canal therapy is the inability to localize and treat all of the canals of the root canal system. (2 Mandibular premolars have complex canal systems. (3 Mandibular premolars have a high risk of missed anatomy. (4 Preoperative radiograph interpretation is essential to evaluate and detect uncommon anatomies. (5 The operating microscope and CBCT interpretation are fundamental in confirming and preventing mistakes about the configuration of mandibular premolars. Riassunto: Obiettivi: Presentare un caso clinico di ritrattamento canalare di un secondo premolare mandibolare con due canali e due radici. Riassunto: Individuare, sagomare, detergere l’intero sistema radicolare presenta una sfida difficile in ambito endodontico e in particolar modo nei premolari mandibolari per il loro complesso sistema canalare. I premolari mandibolari sono spesso considerati i denti più difficili in cui effettuare una terapia endodontica.Vertucci riscontrò che i secondi premolari mandibolari hanno una radice e un canale nel 97.5% e due canali in solo il 2.5%.1Il case report seguente descrive la diagnosi e il ritrattamento di un secondo premolare con due canali in due radici.Punti chiave di apprendimento: 1. La maggior causa di fallimento endodontico �

The ART score is not effective to select patients for transarterial chemoembolization retreatment in an Italian series.

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Terzi, Eleonora; Terenzi, Laura; Venerandi, Laura; Croci, Luca; Renzulli, Matteo; Mosconi, Cristina; Allegretti, Giulia; Granito, Alessandro; Golfieri, Rita; Bolondi, Luigi; Piscaglia, Fabio

2014-01-01

The ART score (a point score for the assessment of retreatment with transarterial chemoembolization, TACE) has been recently developed in Austria to differentiate patients who may benefit from multiple sessions of TACE for hepatocellular carcinoma (HCC) treatment. The primary aim of the study was to test the validity of the ART score in an Italian study cohort. The secondary aims were to evaluate overall survival (OS) and clinical determinants of improved survival in patients treated with multiple TACE sessions. The ART score and the clinical outcome of 51 consecutive patients with HCC submitted to multiple TACE sessions from April 2002 to December 2009 were retrospectively analyzed. Median OS was 26.0 months (95% confidence interval 18.4-33.6) with 1-, 3- and 5-year survival rates of 75, 33 and 11%, respectively). Thirty-three patients had an ART score of 0-1.5 and in 18 it was ≥2.5, but in our patient series, the ART score was not found to be a predictor of survival (p = 0.173). At univariate analysis, tumor extent (uni- vs. bilobar: 34.0 vs. 9.0 months; p < 0.001), Child-Pugh score before the second TACE (A vs. B7 vs. B8-9: 26.0 vs. 16.0 vs. 5.0 months; p = 0.005) and Child-Pugh score increase between the first and second TACE (absent vs. + 1 point vs. + ≥2 points: 27.0 vs. 4.0 vs. 5.0 months; p < 0.001) were statistically related with survival. At multivariate analysis, only Child-Pugh score increase remained a significant predictor of worse survival (p = 0.001, hazard rate = 11.6). The ART score was not found to work as an objective tool to guide TACE retreatment in our Italian patient series, only the Child-Pugh score increase was an independent predictor of a shorter survival.

Evaluation of pre-existing neuropathy and bortezomib retreatment as risk factors to develop severe neuropathy in a mouse model.

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Bruna, Jordi; Alé, Albert; Velasco, Roser; Jaramillo, Jessica; Navarro, Xavier; Udina, Esther

2011-09-01

Pre-existing neuropathy, a not uncommon feature in oncologic patients, is a potential but non-confirmed risk factor to develop early or severe chemotherapy-induced neuropathy. The main goal of this study is to evaluate the role of pre-existing neuropathy induced by vincristine (VNC) or bortezomib (BTZ) as a risk factor to develop more severe BTZ-induced neuropathy in a mouse model. VNC, at doses of 1 and 1.5 mg/kg given twice per week for 4 weeks, induced a moderate and severe sensory-motor neuropathy, primarily axonal, with predominant involvement of myelinated sensory axons. The neuropathy induced by BTZ at dose of 1 mg/kg given twice per week for 6 weeks was a mild axonal sensory neuropathy involving myelinated and unmyelinated fibers. The neuropathy in mice previously treated and retreated with the same schedule of BTZ after 4 weeks of washout period was similar in profile and severity to the one observed after the first treatment. When basal neuropathy was classified as moderate (most of BTZ-treated animals) or severe (all VNC-treated animals and two BTZ-treated animals), there was a more marked decline in sensory nerve function during BTZ retreatment in the group with basal severe neuropathy (-86%) than in the groups with basal mild (-57%) or without neuropathy (-52%; p < 0.001). Histopathological findings supported the functional results. Therefore, this study shows that the presence of a severe neuropathy previous to treatment with an antitumoral agent, such as BTZ, results in a more marked involvement of peripheral nerves. © 2011 Peripheral Nerve Society.

Retreatment of failed regenerative endodontic of orthodontically treated immature permanent maxillary central incisor: a case report

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Musaed Fahad Al-Tammami

2017-02-01

Full Text Available A revascularization procedure was shown to be the best alternative therapy for immature teeth with necrotic pulp and apical infection. A 12 year old female with a history of trauma to her upper central incisor and a sinus tract was referred for endodontic treatment. She was an active orthodontic patient and had undergone regenerative endodontic treatment for the past 2 years. Clinical examination revealed no response to sensibility, percussion, and palpation tests. The preoperative radiograph showed an open apex and apical rarefaction. The case was diagnosed as previously treated tooth with asymptomatic apical periodontitis. Regenerative endodontic retreatment was performed, and the case was followed for 3 years. Clinical, radiographic, and cone-beam computed tomography follow-up examination revealed an asymptomatic tooth, with evidence of periapical healing and root maturation.

Retreatment and maintenance therapy with infliximab in fistulizing Crohn' disease Retratamiento y tratamiento de mantenimiento con infliximab en la enfermedad de Crohn fistulizante

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L. Rodrigo

2004-08-01

Full Text Available Objectives: infliximab has clearly demonstrated its efficacy in the short-term treatment of fistulizing Crohn' disease. We present here the results of retreatment and long-term maintenance therapy. Patients and methods: eighty one consecutive patients with active fistulizing Crohn' disease, in whom previous treatments had failed, were treated with infliximab. All patients received as the initial treatment of 5 mg/kg i.v. infusions (weeks 0, 2, and 6. Those patients who failed to respond after the initial cycle (group 1, n= 25, or those who relapsed after having responded (group 2, n=13, received retreatment with three similar doses (weeks 0,2, and 6. Those who responded to retreatment were included in a long-term maintenance programme (n=44, with repeated doses (5 mg/kg i.v. infusions every eight weeks for 1-2 years. Results: in the initial treatment 56% of the patients responded partially; this response being complete in 44%. In the retreatment, 28% of group 1 (non-responders presented a complete response, compared to 77% in group 2 (relapsers (pObjetivos: el infliximab ha demostrado su eficacia en el tratamiento a corto plazo de la enfermedad de Crohn (EC fistulosa. En este trabajo presentamos los resultados del retratamiento y del tratamiento de mantenimiento a largo plazo. Pacientes y métodos: se trataron con infliximab un total de 81 pacientes consecutivos con EC fistulosa activa, en los cuales, habían fallado tratamientos previos. Todos los pacientes recibieron como tratamiento inicial infusiones a dosis de 5 mg/kg i.v. en las semanas 0, 2 y 6. Aquellos pacientes que no respondieron después del ciclo inicial (grupo 1, n=25, o los que recayeron después de haber respondido (grupo 2, n=13, recibieron retratamiento con 3 dosis similares (semanas 0, 2 y 6. Aquellos que respondieron a la terapia de retratamiento fueron incluidos en un programa de mantenimiento a largo plazo (n=44, con dosis repetidas (infusiones con 5 mg/kg i.v. cada 8

Successful Retreatment of Recurrent Intracranial Vertebral Artery Dissecting Aneurysms After Stent-Assisted Coil Embolization: A Self-Controlled Hemodynamic Analysis.

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Liu, Jian; Jing, Linkai; Zhang, Ying; Song, Ying; Wang, Yang; Li, Chuanhui; Wang, Yanmin; Mu, Shiqing; Paliwal, Nikhil; Meng, Hui; Linfante, Italo; Yang, Xinjian

2017-01-01

Intracranial vertebral artery dissecting aneurysms (VADAs) tend to recur despite successful stent-assisted coil embolization (SACE). Hemodynamics is useful in evaluating aneurysmal formation, growth, and rupture. Our aim was to evaluate the hemodynamic patterns of the recurrence of VADA. Between September 2009 and November 2013, all consecutive patients with recurrent VADAs after SACE in our institutions were enrolled. Recurrence was defined as recanalization and/or regrowth. We assessed the hemodynamic alterations in wall shear stress (WSS) and velocity after the initial SACE and subsequently after retreatment of the aneurysms that recurred. Five patients were included. After the initial treatment, 3 patients showed recanalization and 2 showed regrowth. In the 2 patients with regrowth, the 2 original aneurysms maintained complete occlusion; however, de novo aneurysm regrowth was confirmed near the previous site. Compared with 3 recanalized aneurysms, the completely occluded aneurysms showed high mean reductions in velocity and WSS after initial treatment (velocity, 77.6% vs. 57.7%; WSS, 74.2% vs. 52.4%); however, WSS remained high at the region near the previous lesion where the new aneurysm originated. After the second retreatment, there was no recurrence in any patient. Compared with the 3 aneurysms that recanalized, the 4 aneurysms that maintained complete occlusion showed higher reductions in velocity (62.9%) and WSS (71.1%). Our series indicated that hemodynamics might have an important role in recurrence of VADAs. After endovascular treatment, sufficient hemodynamic reduction in aneurysm dome, orifice, and parent vessel may be one of the key factors for preventing recurrence in VADAs. Copyright © 2016 Elsevier Inc. All rights reserved.

Impact of treatment and re-treatment with artemether-lumefantrine and artesunate-amodiaquine on selection of Plasmodium falciparum multidrug resistance gene-1 polymorphisms in the Democratic Republic of Congo and Uganda

DEFF Research Database (Denmark)

Baraka, Vito; Mavoko, Hypolite Muhindo; Nabasumba, Carolyn

2018-01-01

fragment length polymorphism (RFLP) assays. RESULTS: The pre-treatment prevalence of Pfmdr1 N86 and D1246Y varied significantly between the sites, (p>0.001) and (p = 0.013), respectively. There was borderline significant directional selection for Pfmdr1 184F in recurrent malaria infections after treatment...... with AL in Uganda site (p = 0.05). Pfmdr1 NFD haplotype did not significantly change in post-treatment infections after re-treatment with either AL or ASAQ. Comparison between pre-treatment and post-treatment recurrences did not indicate directional selection of Pfmdr1 N86, D1246 alleles in the pre......BACKGROUND: The emergence of resistance against artemisinin combination treatment is a major concern for malaria control. ACTs are recommended as the rescue treatment, however, there is limited evidence as to whether treatment and re-treatment with ACTs select for drug-resistant P. falciparum...

The water erosion processes in the retreat erosive of cliff on soft rocks in the province of Cadiz (Spain)

International Nuclear Information System (INIS)

Rendon Aragon, J. J.; Gracia Prieto, F. J.; Rio Rodriguez, L. del

2009-01-01

The littoral cliffs on soft materials of the Atlantic Cadiz coast show an important activity of the fresh water erosion processes, sometimes even more significant than the marine erosion processes. The connection of the lower cliffs with sandy beaches favours aeolian sand invasion, which fills previous rills and reduces the water erosion intensity by increasing infiltration. Cliff retreat and rill erosion measurement by using erosion sticks has shown very variables values, most of them higher than the estimated error of the employed methods. This indicates the existence of other factors influencing the distribution of water erosion processes along these cliffs, which have to be studied through different techniques. (Author) 5 refs.

The retreat of the world's mountain glaciers during recent decades; Le retrait des glaciers de montagne dans le monde au cours des dernieres decennies

Energy Technology Data Exchange (ETDEWEB)

Francou, B. [Institut de Recherche pour le Developpement (IRD), Mission de Quito, Equateur - LTHE, 38 - Grenoble (France); Vincent, Ch. [Centre National de la Recherche Scientifique (CNRS), UJF, LGGE, 38 - Grenoble (France)

2009-08-15

Glaciers have become essential tools for measuring changes in the global environment. Here, we analyze glacier evolution during the last few decades and we wonder whether the observed retreat remains in the range of glacier fluctuations since the mid-Holocene. The main fluctuations experienced by glaciers during the last millenniums, and particularly during the Little Ice Age (-1300 A.D. to {approx}1860 A.D.), are presented succinctly. The recent 1960-2005 period, well documented both by ground and remote sensing observations, shows important disparities between different massifs concerning the timing and the magnitude of glacier fluctuations, which depend on regional climatic conditions. The links between glacier mass balance evolution and climate is clear when approached from an energy balance but the variables commonly considered are only temperature and precipitation. The strong correlation existing between these variables and the mass balance evolution makes it possible to simulate glaciers in the future in function of distinct climatic scenarios. Modeling glacier retreat for the 21. century is an important goal because it will allow the impacts on water resource and sea level to be assessed. (authors)

Application of safety checklist to the analysis of the IEA-R1 reactor water retreatment system; Utilizacao do checklist de seguranca na analise do sistema de retratamento de agua do reator IEA-R1

Energy Technology Data Exchange (ETDEWEB)

Sauer, Maria Eugenia Lago Jacques; Sara Neto, Antonio Jorge; Lima, Toni Carlos Caboclo de; Ribeiro, Maria Alice Morato [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: melsauer@ipen.br

2005-07-01

In 1999, the management of the IEA-R1 Research Reactor (pool type - 5 MWth), located at IPEN/CNEN-SP, started the evaluation of the Reactor Pool Water Retreatment System to identify operational aspects, which could compromise the operators safety. The purpose was to identify and propose enhancements to the system which would be installed to substitute for the existing one. This process was conducted through a qualitative study of the system in operation. This study was carried out by a team composed of specialists in reactor operation, systems maintenance and radiological protection, and one safety analyst. The study consisted, basically, in local inspections to verify the physical and operational conditions of each equipment / component as well as aspects related to maintenance activities of the system. The process control and the operator procedures associated with the retreatment of the reactor pool water were also reviewed. The methodology adopted to develop the study was based in process hazard analysis technique named Safety Checklist. This paper presents a summary of this study and the main results obtained. Some operational and safety problems identified, the prevention and/or correction means to avoid them, and the recommendations and suggestions that have been implemented to the new design of the IEA-R1 Reactor Water Retreatment System, whose installation was concluded in 2003, are also presented. (author)

Foreland sedimentary record of Andean mountain building during advancing and retreating subduction

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Horton, Brian K.

2016-04-01

-skinned basement inversion with geometrically and kinematically linked thin-skinned thrust structures at shallower levels in the eastern foreland, including well-dated late Miocene growth strata. The mid-Cenozoic hiatus potentially signifies nondeposition during passage of a flexural forebulge or nondeposition during neutral to extensional conditions possibly driven by a transient retreating-slab configuration along the western margin of South America. Similar long-lived stratigraphic gaps are commonly observed in other foreland records of continental convergent margins. It is proposed that Andean orogenesis along the South American convergent margin has long been sensitive to variations in subduction dynamics throughout Mesozoic-Cenozoic time, such that shifts in relative convergence and degree of mechanical coupling along the subduction interface (i.e., transitions between advancing versus retreating modes of subduction) have governed fluctuating contractional, extensional, and neutral conditions. Unclear is whether these various modes affected the entire convergent margin simultaneously due to continental-scale changes (e.g., temporal shifts in plate convergence, absolute motion of upper plate, or mantle wedge circulation) or whether parts of the margin behaved independently due to smaller-scale fluctuations (e.g., spatial variations in the age of the subducted plate, buoyant asperities in the downgoing slab, or asthenospheric anomalies).

GIS-based analysis and modelling with empirical and remotely-sensed data on coastline advance and retreat

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Ahmad, Sajid Rashid

With the understanding that far more research remains to be done on the development and use of innovative and functional geospatial techniques and procedures to investigate coastline changes this thesis focussed on the integration of remote sensing, geographical information systems (GIS) and modelling techniques to provide meaningful insights on the spatial and temporal dynamics of coastline changes. One of the unique strengths of this research was the parameterization of the GIS with long-term empirical and remote sensing data. Annual empirical data from 1941--2007 were analyzed by the GIS, and then modelled with statistical techniques. Data were also extracted from Landsat TM and ETM+ images. The band ratio method was used to extract the coastlines. Topographic maps were also used to extract digital map data. All data incorporated into ArcGIS 9.2 were analyzed with various modules, including Spatial Analyst, 3D Analyst, and Triangulated Irregular Networks. The Digital Shoreline Analysis System was used to analyze and predict rates of coastline change. GIS results showed the spatial locations along the coast that will either advance or retreat over time. The linear regression results highlighted temporal changes which are likely to occur along the coastline. Box-Jenkins modelling procedures were utilized to determine statistical models which best described the time series (1941--2007) of coastline change data. After several iterations and goodness-of-fit tests, second-order spatial cyclic autoregressive models, first-order autoregressive models and autoregressive moving average models were identified as being appropriate for describing the deterministic and random processes operating in Guyana's coastal system. The models highlighted not only cyclical patterns in advance and retreat of the coastline, but also the existence of short and long-term memory processes. Long-term memory processes could be associated with mudshoal propagation and stabilization while short

The effectiveness of retreatment with peginterferon alfa and ribavirin in patients with chronic viral hepatitis C genotype 2 and 3: a prospective cohort study in Brazil.

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Artico, Simara; Amaral, Karine Medeiros; Gonçalves, Candice Beatriz Treter; Picon, Paulo Dornelles

2012-12-27

More than 50% of patients infected with chronic hepatitis C virus (HCV) do not respond to treatment with conventional interferon (IFN) combined with ribavirin (RBV). The aim of our study was to evaluate the effectiveness of retreatment with peginterferon alfa-2a or 2b (PEG-IFN 2a or 2b) concomitantly with RBV in patients with HCV genotype 2 and 3, which were non-responders or relapsers to initial treatment with IFN / RBV and to identify possible predictors of sustained virological response (SVR). From September 2003 to March 2009 a cohort of 216 patients who had previously failed therapy with a regimen of standard interferon and ribavirin, were followed in a specialized service implemented in the Brazilian Unified Health System, Rio Grande do Sul. All patients were retreated with PEG-IFN 2a or 2b per week, associated with RBV, through oral route, with doses determined according to weight (1,000 mg if weight ≤ 75 Kg and 1,250 mg if ≥ 75 Kg) per day for 48 weeks. The HCV-RNA was tested by Polymerase Chain Reaction (PCR). Virological Response (VR) within 48 weeks and SVR in the 72 weeks was considered for evaluation of treatment efficacy. Analyses were performed in patients who received at least one dose of PEG-IFN. The SVR rate for non-responders to previous treatment was 34.4% and for relapsers was 50% (p = 0.031). As predictive factors that contribute to improve SVR, were identified the age (p = 0.005), to be relapsers to previous treatment (p = 0.023) and present liver biopsy examination Metavir F0-F2 (p = 0.004). In assessing the safety profile, 51 patients (23.6%) discontinued treatment prematurely. This alternative retreatment for patients who have failed prior therapies for anti-HCV, has demonstrated promising SVR rate, provided that it includes a careful selection of patients with predictors of response and adverse events monitored.

The effectiveness of retreatment with peginterferon alfa and ribavirin in patients with chronic viral hepatitis C genotype 2 and 3: a prospective cohort study in Brazil

Directory of Open Access Journals (Sweden)

Artico Simara

2012-12-01

Full Text Available Abstract Background More than 50% of patients infected with chronic hepatitis C virus (HCV do not respond to treatment with conventional interferon (IFN combined with ribavirin (RBV. The aim of our study was to evaluate the effectiveness of retreatment with peginterferon alfa-2a or 2b (PEG-IFN 2a or 2b concomitantly with RBV in patients with HCV genotype 2 and 3, which were non-responders or relapsers to initial treatment with IFN / RBV and to identify possible predictors of sustained virological response (SVR. Methods From September 2003 to March 2009 a cohort of 216 patients who had previously failed therapy with a regimen of standard interferon and ribavirin, were followed in a specialized service implemented in the Brazilian Unified Health System, Rio Grande do Sul. All patients were retreated with PEG-IFN 2a or 2b per week, associated with RBV, through oral route, with doses determined according to weight (1,000 mg if weight ≤ 75 Kg and 1,250 mg if ≥ 75 Kg per day for 48 weeks. The HCV-RNA was tested by Polymerase Chain Reaction (PCR. Virological Response (VR within 48 weeks and SVR in the 72 weeks was considered for evaluation of treatment efficacy. Analyses were performed in patients who received at least one dose of PEG-IFN. Results The SVR rate for non-responders to previous treatment was 34.4% and for relapsers was 50% (p = 0.031. As predictive factors that contribute to improve SVR, were identified the age (p = 0.005, to be relapsers to previous treatment (p = 0.023 and present liver biopsy examination Metavir F0-F2 (p = 0.004. In assessing the safety profile, 51 patients (23.6% discontinued treatment prematurely. Conclusions This alternative retreatment for patients who have failed prior therapies for anti-HCV, has demonstrated promising SVR rate, provided that it includes a careful selection of patients with predictors of response and adverse events monitored.

Mandibular second premolar with three canals: Re-treatment of a case with unusual root canal anatomy

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Niranjan Desai

2011-01-01

Full Text Available A thorough knowledge of root canal anatomy along with the anatomical variations that may be present is essential for success of endodontic therapy. Unusual presentations in the number of the roots or the canals should be expected in every tooth. Mandibular second premolars are thought of as having a single root and canal. Studies have stated that the prevalence of three canals with three orifices in this tooth is 0.4%. The mandibular second premolar is particularly difficult to treat owing to the fact that a wide variation in the number, location and curvature of the roots and canals exist. Added to this is the fact that the access opening is restricted and location of the lingually placed orifices is difficult. This case report details the re-treatment of a mandibular second premolar with three canals and three separate orifices using the surgical microscope.

Particularism and the retreat from theory in the archaeology of agricultural origins.

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Gremillion, Kristen J; Barton, Loukas; Piperno, Dolores R

2014-04-29

The introduction of new analytic methods and expansion of research into previously untapped regions have greatly increased the scale and resolution of data relevant to the origins of agriculture (OA). As a result, the recognition of varied historical pathways to agriculture and the continuum of management strategies have complicated the search for general explanations for the transition to food production. In this environment, higher-level theoretical frameworks are sometimes rejected on the grounds that they force conclusions that are incompatible with real-world variability. Some of those who take this position argue instead that OA should be explained in terms of local and historically contingent factors. This retreat from theory in favor of particularism is based on the faulty beliefs that complex phenomena such as agricultural origins demand equally complex explanations and that explanation is possible in the absence of theoretically based assumptions. The same scholars who are suspicious of generalization are reluctant to embrace evolutionary approaches to human behavior on the grounds that they are ahistorical, overly simplistic, and dismissive of agency and intent. We argue that these criticisms are misplaced and explain why a coherent theory of human behavior that acknowledges its evolutionary history is essential to advancing understanding of OA. Continued progress depends on the integration of human behavior and culture into the emerging synthesis of evolutionary developmental biology that informs contemporary research into plant and animal domestication.

The Safe Harbor Mouse Retreat(™) is an innovative enrichment shelter that saves mice and money.

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Froberg-Fejko, Karen M; Lecker, Jaime L

2013-10-01

Environmental enrichment can be defined as altering the living environment of captive animals in order to provide them with opportunities to express their natural behavioral repertoire. As important as offering an enriched environment is assuring lab animals are housed in the safest conditions possible. Cage flooding events are an unfortunate reality; however, technology is advancing to minimize these events. Bio-Serv, in collaboration with Allentown, Inc., has developed an innovative and economical shelter called the Safe Harbor Mouse Retreat (Fig. 1). This shelter offers a life-saving refuge for mice during these occasional, but devastating cage-flooding accidents. Mice will not be lost due to chilling or drowning caused by water exposure. Breeding mice can save their litters by moving their pups to the second level, and all mice can escape to the higher level where they can remain warm and dry until they are rescued. This clever shelter is not only life-saving for mice but offers several other significant benefits as well.

Mentored residential writing retreats: a leadership strategy to develop skills and generate outcomes in writing for publication.

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Jackson, Debra

2009-01-01

There is an increasing expectation that academic and clinical nurses will contribute to disciplinary and professional discourses through scholarly writing. However, the difficulties and challenges associated with writing for publication mean that many papers will never be written. This current paper describes an innovative approach developed to support skill development and outcomes in writing for publication. Intensive residential writing retreats informed by the principles of servant leadership and incorporating strategies such as mentoring and peer learning were conducted in 2005 and 2007. Positive outcomes and benefits included publications submitted to peer-reviewed journals, as well as positive effects on collegial relationships, and team building. Novice writers benefited from intensive and sustained support and coaching by experienced writers. Organisational benefits included increased participation by staff and research higher degree students in publication activities, enhanced collegial relationships and opportunities for senior established writers to work with inexperienced writers.

Giant seafloor craters formed by hydrate-controlled large-scale methane expulsion from the Arctic seafloor after ice sheet retreat

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Andreassen, K.; Hubbard, A.; Patton, H.; Vadakkepuliyambatta, S.; Winsborrow, M.; Plaza-Faverola, A. A.; Serov, P.

2017-12-01

Large-scale methane releases from thawing Arctic gas hydrates is a major concern, yet the processes and fluxes involved remain elusive. We present geophysical data indicating two contrasting processes of natural methane emissions from the seafloor of the northern Barents Sea, Polar North Atlantic. Abundant gas flares, acoustically imaged in the water column reveal slow, gradual release of methane bubbles, a process that is commonly documented from nearby areas, elsewhere in the Arctic and along continental margins worldwide. Conversely, giant craters across the study area indicate a very different process. We propose that these are blow-out craters, formed through large-scale, abrupt methane expulsion induced when gas hydrates destabilized after the Barents Sea Ice Sheet retreated from the area. The data reveal over 100 giant seafloor craters within an area of 440 km2. These are up to 1000 m in diameter, 30 m deep and with a semi-circular to elliptical shape. We also identified numerous large seafloor mounds, which we infer to have formed by the expansion of gas hydrate accumulations within the shallow subsurface, so-called gas hydrate pingos. These are up to 1100 m wide and 20 m high. Smaller craters and mounds < 200 m wide and with varying relief are abundant across the study site. The empirical observations and analyses are combined with numerical modelling of ice sheet, isostatic and gas hydrate evolution and indicate that during glaciation, natural gas migrating from underlying hydrocarbon reservoirs was stored as subglacial gas hydrates. On ice sheet retreat, methane from these hydrate reservoirs and underlying free gas built up and abruptly released, forming the giant mounds and craters observed in the study area today. Petroleum basins are abundant beneath formerly and presently glaciated regions. We infer that episodes of subglacial sequestration of gas hydrates and underlying free gas and subsequent abrupt expulsions were common and widespread throughout

The sanctuary of empathy and the invitation of engagement: psychic retreat, Kafka's "A Hunger Artist," and the psychoanalytic process.

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Karbelnig, Alan Michael

2014-12-01

As part of a broader scholarly and political effort to unify clinical psychoanalysis, the author argues that psychoanalysts' presence, engagement, and framing constitute the three overarching features of their work. Additionally, patients' propensity to turn inward, alternatively known as psychic retreat or narcissistic withdrawal, provides a similarly unifying way to view psychoanalytic patients. Narrowing the investigation to a phenomenological one, the author tapers the exploration further by studying the psychoanalytic process as it unfolds in real time. After addressing the problems of diffusion in professional identity and psychoanalytic theory that have plagued psychoanalysis from the start, the author presents three case examples into which he integrates Kafka's short story "A Hunger Artist." These vehicles are utilized to demonstrate how such nomenclature provides the basis for a more cohesive understanding of how psychoanalysts work.

Analytical analysis of the temporal asymmetry between seawater intrusion and retreat

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Rathore, Saubhagya Singh; Zhao, Yue; Lu, Chunhui; Luo, Jian

2018-01-01

The quantification of timescales associated with the movement of the seawater-freshwater interface is useful for developing effective management strategies for controlling seawater intrusion (SWI). In this study, for the first time, we derive an explicit analytical solution for the timescales of SWI and seawater retreat (SWR) in a confined, homogeneous coastal aquifer system under the quasi-steady assumption, based on a classical sharp-interface solution for approximating freshwater outflow rates into the sea. The flow continuity and hydrostatic equilibrium across the interface are identified as two primary mechanisms governing timescales of the interface movement driven by an abrupt change in discharge rates or hydraulic heads at the inland boundary. Through theoretical analysis, we quantified the dependence of interface-movement timescales on porosity, hydraulic conductivity, aquifer thickness, aquifer length, density ratio, and boundary conditions. Predictions from the analytical solution closely agreed with those from numerical simulations. In addition, we define a temporal asymmetry index (the ratio of the SWI timescale to the SWR timescale) to represent the resilience of the coastal aquifer in response to SWI. The developed analytical solutions provide a simple tool for the quick assessment of SWI and SWR timescales and reveal that the temporal asymmetry between SWI and SWR mainly relies on the initial and final values of the freshwater flux at the inland boundary, and is weakly affected by aquifer parameters. Furthermore, we theoretically examined the log-linearity relationship between the timescale and the freshwater flux at the inland boundary, and found that the relationship may be approximated by two linear functions with a slope of -2 and -1 for large changes at the boundary flux for SWI and SWR, respectively.

Future increases in Arctic precipitation linked to local evaporation and sea-ice retreat.

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Bintanja, R; Selten, F M

2014-05-22

Precipitation changes projected for the end of the twenty-first century show an increase of more than 50 per cent in the Arctic regions. This marked increase, which is among the highest globally, has previously been attributed primarily to enhanced poleward moisture transport from lower latitudes. Here we use state-of-the-art global climate models to show that the projected increases in Arctic precipitation over the twenty-first century, which peak in late autumn and winter, are instead due mainly to strongly intensified local surface evaporation (maximum in winter), and only to a lesser degree due to enhanced moisture inflow from lower latitudes (maximum in late summer and autumn). Moreover, we show that the enhanced surface evaporation results mainly from retreating winter sea ice, signalling an amplified Arctic hydrological cycle. This demonstrates that increases in Arctic precipitation are firmly linked to Arctic warming and sea-ice decline. As a result, the Arctic mean precipitation sensitivity (4.5 per cent increase per degree of temperature warming) is much larger than the global value (1.6 to 1.9 per cent per kelvin). The associated seasonally varying increase in Arctic precipitation is likely to increase river discharge and snowfall over ice sheets (thereby affecting global sea level), and could even affect global climate through freshening of the Arctic Ocean and subsequent modulations of the Atlantic meridional overturning circulation.

Impact of Arctic sea-ice retreat on the recent change in cloud-base height during autumn

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Sato, K.; Inoue, J.; Kodama, Y.; Overland, J. E.

2012-12-01

Cloud-base observations over the ice-free Chukchi and Beaufort Seas in autumn were conducted using a shipboard ceilometer and radiosondes during the 1999-2010 cruises of the Japanese R/V Mirai. To understand the recent change in cloud base height over the Arctic Ocean, these cloud-base height data were compared with the observation data under ice-covered situation during SHEBA (the Surface Heat Budget of the Arctic Ocean project in 1998). Our ice-free results showed a 30 % decrease (increase) in the frequency of low clouds with a ceiling below (above) 500 m. Temperature profiles revealed that the boundary layer was well developed over the ice-free ocean in the 2000s, whereas a stable layer dominated during the ice-covered period in 1998. The change in surface boundary conditions likely resulted in the difference in cloud-base height, although it had little impact on air temperatures in the mid- and upper troposphere. Data from the 2010 R/V Mirai cruise were investigated in detail in terms of air-sea temperature difference. This suggests that stratus cloud over the sea ice has been replaced as stratocumulus clouds with low cloud fraction due to the decrease in static stability induced by the sea-ice retreat. The relationship between cloud-base height and air-sea temperature difference (SST-Ts) was analyzed in detail using special section data during 2010 cruise data. Stratus clouds near the sea surface were predominant under a warm advection situation, whereas stratocumulus clouds with a cloud-free layer were significant under a cold advection situation. The threshold temperature difference between sea surface and air temperatures for distinguishing the dominant cloud types was 3 K. Anomalous upward turbulent heat fluxes associated with the sea-ice retreat have likely contributed to warming of the lower troposphere. Frequency distribution of the cloud-base height (km) detected by a ceilometer/lidar (black bars) and radiosondes (gray bars), and profiles of potential

Large-scale retreat and advance of shallow seas in Southeast Asia driven by mantle flow

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Zahirovic, Sabin; Flament, Nicolas; Dietmar Müller, R.; Seton, Maria; Gurnis, Michael

2016-04-01

The Indonesian islands and surrounding region represent one of the most submerged, low-lying continental areas on Earth. Almost half of this region, known as Sundaland, is presently inundated by a shallow sea. The role of mantle convection in driving long-wavelength topography and vertical motion of the lithosphere in this region has largely been ignored when interpreting regional stratigraphic sections, despite a consensus that Southeast Asia presently situated on a "dynamic topography low" resulting from long-term post-Pangea subduction. However, dynamic topography is typically described as a temporally and spatially transient process, implying that Sundaland may have experienced significant vertical motions in the geological past, and thus must be considered when interpreting relative sea level changes and the paleogeographic indicators of advancing and retreating shallow seas. Although the present-day low regional elevation has been attributed to the massive volume of oceanic slabs sinking in the mantle beneath Southeast Asia, a Late Cretaceous to Eocene regional unconformity indicates that shallow seas retreated following regional flooding during the mid-Cretaceous sea level highstand. During the Eocene, less than one fifth of Sundaland was submerged, despite global sea level being ~200 m higher than at present. The regional nature of the switch from marine to terrestrial environments, that is out-of-sync with eustatic sea levels, suggests that broad mantle-driven dynamic uplift may have led to the emergence of Sundaland in the Late Cretaceous and Paleocene. We use numerical forward modelling of plate tectonics and mantle convection, and compare the predicted trends of dynamic topography with evidence from regional paleogeography and eustasy to determine the extent to which mantle-driven vertical motions of the lithosphere have influenced regional basin histories in Southeast Asia. A Late Cretaceous collision of Gondwana-derived terranes with Sundaland choked

Dry-season retreat and dietary shift of the dart-poison frog Dendrobates tinctorius (Anura: Dendrobatidae

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Marga Born

2010-07-01

Full Text Available Seasonal rainfall affects tropical forest dynamics and behaviorof species that are part of these ecosystems. The positive correlation between amphibian activity patterns and rainfall has been demonstrated repeatedly. Members of Dendrobatidae, a clade of Neotropical dart-poison frogs, are well known for their habitat use and behavior during the rainy season, but their behavior during the dry season has received little attention. We studied habitat use and diet of the dendrobatid frog Dendrobates tinctorius in French Guiana during the rainy and dry seasons. Unlike many other dendrobatid frogs, D. tinctorius does not maintain territories for the entire rainy season. Both sexes colonize recently formed canopy-gaps and stay in these forest patches for only a few weeks. The frogs inthese patches consume a great diversity of prey, consisting of ants, beetles, wasps, insect larvae, and mites. During the dry season, frogs move to retreat sites in mature forest, such as palm bracts and tree holes. The frogs are less active and consume fewer prey items in the dry season, and they consume fewer wasps and insect larvae, but more termites. Ants are the most common prey items during both the wet and dry seasons. We discuss the effects of shifts in seasonal habitat use on the territorial behavior of dendrobatid frogs.

Heat Retreat Locations in Cities - The Survey-Based Location Analysis of Heat Relief

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Neht, Alice; Maximini, Claudia; Prenger-Berninghoff, Kathrin

2017-12-01

The adaptation of cities to climate change effects is one of the major strategies in urban planning to encounter the challenges of climate change (IPCC 2014). One of the fields of climate change adaption is dealing with heat events that occur more frequently and with greater intensity. Cities in particular are vulnerable to these events due to high population and infrastructure density. Proceeding urbanization calls for the existence of sufficient heat retreat locations (HRL) to enable relief for the population from heat in summer. This is why an extensive analysis of HRL is needed. This paper aims at the development of a survey-based location analysis of heat relief by identifying user groups, locations and characteristics of HRL based on a home survey that was conducted in three German cities. Key results of the study show that the majority of the participants of the survey are users of existing HRL, are affected by heat, and perceive heat as a burden in summer. Moreover, HRL that are located in close proximity are preferred by most users while their effect depends on the regional context that has to be considered in the analysis. Hence, this research presents an approach to heat relief that underlines the importance of HRL in cities by referring to selected examples of HRL types in densely populated areas of cities. HRL should especially be established and secured in densely built-up areas of cities. According to results of the survey, most HRL are located in public spaces, and the overall accessibility of HRL turned out to be an issue.

Reconstructing the evolution of a deep seated rockslide (Marzell) and its response to glacial retreat based on historic and remote sensing data

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Fey, Christine; Wichmann, Volker; Zangerl, Christian

2017-12-01

In this study a combination of different topographic data from historic topographic maps and remote sensing is used to reconstruct and monitor the behaviour of the high alpine ice contact rockslide system Marzell and its response to glacial debuttressing in the Eastern Alps. Topographic data from archives (historical topographic maps, national glacier inventories, aerial images, orthoimages and ALS data) and data from monitoring campaigns (geodetic measurements, terrestrial laser scanning and UAV imaging campaigns) are processed to georeferenced images and/or elevation data, respectively. The data from different data sources is compiled and analysed with the aim to i) reconstruct the extent, thickness and volume changes of the glacier since 1893 and ii) to analyse the rockslide deformation evolution by extracting information about the displacement direction, dip angle, velocity and partial failure of rockslide slabs since 1951. The rockslide is compound of different rockslide slabs which move downwards as rigid blocks along basal shear zones. The analyses and interpretation of the data suggest a rotational type of rockslide failure mechanisms. The rockslide activity correlates with the ice volume loss at the adjacent part of the glacier. In the period between 1971 and 1997 the annual average rockslide activity was about 0.05 m/a and the annual average ice thickness loss was 0.1 m/a. Since the end of the last century the annual average ice thickness loss increased dramatically to 5 m/a. In that period the rockslide activity accelerated. The highest rockslide activity (up to 1.5 m/a) was observed in the 2000s when half of the slope toe was exposed because of glacier retreat. Since 2010 a deceleration of the rockslide can be observed. In the vicinity of the rockslide the glacier almost disappeared and lost 99.88% of its ice volume between 1893 and 2014. The geomorphological and geological information gathered about the rockslide evolution and the glacier retreat form

Small scale tests on the progressive retreat of soil slopes

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Voulgari, Chrysoula; Utili, Stefano; Castellanza, Riccardo

2015-04-01

In this paper, the influence due to the presence of cracks on the morphologic evolution of natural cliffs subject to progressive retreat induced by weathering is investigated through small scale laboratory tests. Weathering turns hard rocks into soft rocks that maintain the structure of the intact rocks, but are characterised by higher void ratios and reduced bond strengths; soft rocks are transformed into granular soils generally called residual soils. A number of landslides develop in slopes due to weathering which results in the progressive retrogression of the slope face and the further degradation within the weathering zone. Cracks, that are widely present, can be a result of weathering and they can cause a significant decrease in their stability, as they provide preferential flow channels which increase the soil permeability and decrease the soil strength. The geological models employed until now are mainly empirical. Several researchers have tried to study the stability of slopes through experimental procedures. Centrifuge modelling is widely used to investigate the failure of slopes. Small scale tests are also an important approach, in order to study the behaviour of a slope under certain conditions, such as the existence of water, as they allow the observation of the infiltration processes, the movement of the weathering front, deformation and failure. However, the deformation response of a slope subject to weathering is not yet thoroughly clarified. In this work, a set of experiments were conducted to investigate weathering induced successive landslides. Weathering was applied to the slope model by wetting the slope crest through a rainfall simulator device. The moisture content of the soil during the tests was monitored by soil moisture sensors that were buried inside the slope model. High resolution cameras were recording the behaviour of the slope model. GeoPIV was used to analyse the frames and obtain the deformations of the slope model during the

Trastuzumab re-treatment following adjuvant trastuzumab and the importance of distant disease-free interval: the HERA trial experience.

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Metzger-Filho, Otto; de Azambuja, Evandro; Procter, Marion; Krieguer, Magalie; Smith, Ian; Baselga, Jose; Cameron, David; Untch, Michael; Jackisch, Christian; Bell, Richard; Gianni, Luca; Goldhirsch, Aron; Piccart, Martine; Gelber, Richard D

2016-01-01

This retrospective analysis conducted using data from patients enrolled onto the Herceptin Adjuvant has two objectives: The first is to evaluate the impact of the time interval between the end of adjuvant trastuzumab and distant recurrence (TDRI) upon overall survival (OS). The second is to describe the duration of trastuzumab-based regimens in the metastatic setting for patients previously treated with adjuvant trastuzumab. The first objective included 187 patients treated with adjuvant trastuzumab and diagnosed with distant recurrence at 4-year median follow-up. The second objective included data from questionnaires sent to investigators retreating patients with trastuzumab upon distant recurrence: 144 of 156 questionnaires were returned (93 %), and 90 patients were selected based on available clinical information and consent for subsequent studies. There was no statistically significant relationship between TDRI following 1 year of adjuvant trastuzumab and OS from distant recurrence: hazard ratio 0.991, p = 0.46. The median OS from distant recurrence was numerically longer among patients with a TDRI of ≥12 months (n = 103) than information beyond disease progression should be included in future clinical studies.

Assembly patterns of soil-dwelling lichens after glacier retreat in the European Alps.

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Nascimbene, Juri; Mayrhofer, Helmut; Dainese, Matteo; Bilovitz, Peter Othmar

2017-06-01

To assess the spatial-temporal dynamics of primary succession following deglaciation in soil-dwelling lichen communities. European Alps (Austria, Switzerland and Italy). Five glacier forelands subjected to relevant glacier retreat during the last century were investigated. In each glacier foreland, three successional stages were selected at increasing distance from the glacier, corresponding to a gradient of time since deglaciation between 25 and 160 years. In each successional stage, soil-dwelling lichens were surveyed within five 1 × 1 m plots. In addition to a classical ecological framework, based on species richness and composition, we applied a functional approach to better elucidate community assembly mechanisms. A positive relationship was found between species richness and time since deglaciation indicating that richer lichen communities can be found at increasing terrain ageing. This pattern was associated with compositional shifts, suggesting that different community assemblages can be found along the successional stages. The analysis of β-diversity revealed a significant nested pattern of species assemblages along the gradient (i.e. earlier successional stages hosted a subset of the species already established in older successional stages), while the turnover component was less relevant. Considering functional groups, we found contrasting patterns in relation to time since deglaciation: the incidence of species with a cyanobacterial photobiont and those reproducing by spores decreased, while that of species reproducing by vegetative propagules increased. This study reveals that community assembly patterns of soil-dwelling lichens in alpine glacier forelands are ruled by mechanisms of directional species accumulation and trait selection that involve a trade-off between different functional strategies. Functional traits that reflect the dispersal and adaptation capability of the species underpin the colonization success of soil-dwelling lichens in

Relevance of the clustered regularly interspaced short palindromic repeats of Enterococcus faecalis strains isolated from retreatment root canals on periapical lesions, resistance to irrigants and biofilms.

Science.gov (United States)

Tong, Zhongchun; Du, Yu; Ling, Junqi; Huang, Lijia; Ma, Jinglei

2017-12-01

A high prevalence of Enterococcus faecalis ( E. faecalis ) is observed in teeth with root canal treatment failures. Clustered regularly interspaced short palindromic repeats (CRISPR) are widely distributed in prokaryotes that have adaptive immune systems against mobile elements, including pathogenic genes. The present study investigated the relevance of the CRISPR in E. faecalis strains isolated from retreated root canals on biofilms, periapical lesions and drug resistance. A total of 20 E. faecalis strains were extracted from the root canals of teeth referred for root canal retreatment. CRISPR-Cas loci were identified by two pairs of relevant primers and polymerase chain reaction. The susceptibility of the 20 isolated strains to intracanal irrigants was evaluated by 1- and 5-minute challenges with a mixture of a tetracycline isomer, an acid and a detergent (MTAD), 2% chlorhexidine (CHX) and 5.25% sodium hypochlorite (NaOCl). The microtiter plate assay and crystal violet staining were used to compare the biofilm formation of the E. faecalis isolate strains. Out of the 20 E. faecalis isolate strains, 5 strains that lacked CRISPR-cas determinants exhibited significant periapical lesions. Among the 15 strains containing CRISPR-cas determinants, 8 were isolated from root canals with inadequate fillings and 7 were isolated from root canals without any fillings. The five strains lacking CRISPR-cas loci were observed to be more resistant to MTAD and 2% CHX than the 15 strains that had CRISPR-cas loci. All of the strains exhibited the same susceptibility to 5.25% NaOCl. Furthermore, the 5 strains lacking CRISPR-cas determinants generated more biofilm than the other 15 strains. Thus, the results of the present study suggested that E. faecalis root canal isolates lacking CRISPR-cas exhibit higher resistance to intracanal irrigants, stronger biofilm formation and generate significant periapical lesions.

Sea-level rise and shoreline retreat: time to abandon the Bruun Rule

Science.gov (United States)

Cooper, J. Andrew G.; Pilkey, Orrin H.

2004-11-01

In the face of a global rise in sea level, understanding the response of the shoreline to changes in sea level is a critical scientific goal to inform policy makers and managers. A body of scientific information exists that illustrates both the complexity of the linkages between sea-level rise and shoreline response, and the comparative lack of understanding of these linkages. In spite of the lack of understanding, many appraisals have been undertaken that employ a concept known as the "Bruun Rule". This is a simple two-dimensional model of shoreline response to rising sea level. The model has seen near global application since its original formulation in 1954. The concept provided an advance in understanding of the coastal system at the time of its first publication. It has, however, been superseded by numerous subsequent findings and is now invalid. Several assumptions behind the Bruun Rule are known to be false and nowhere has the Bruun Rule been adequately proven; on the contrary several studies disprove it in the field. No universally applicable model of shoreline retreat under sea-level rise has yet been developed. Despite this, the Bruun Rule is in widespread contemporary use at a global scale both as a management tool and as a scientific concept. The persistence of this concept beyond its original assumption base is attributed to the following factors: Appeal of a simple, easy to use analytical model that is in widespread use. Difficulty of determining the relative validity of 'proofs' and 'disproofs'. Ease of application. Positive advocacy by some scientists. Application by other scientists without critical appraisal. The simple numerical expression of the model. Lack of easy alternatives. The Bruun Rule has no power for predicting shoreline behaviour under rising sea level and should be abandoned. It is a concept whose time has passed. The belief by policy makers that it offers a prediction of future shoreline position may well have stifled much

Nile Delta exhibited a spatial reversal in the rates of shoreline retreat on the Rosetta promontory comparing pre- and post-beach protection

Science.gov (United States)

Ghoneim, Eman; Mashaly, Jehan; Gamble, Douglas; Halls, Joanne; AbuBakr, Mostafa

2015-01-01

The coastline of the Nile Delta experienced accelerated erosion since the construction of the Aswan High Dam in 1964 and, consequently, the entrapment of a large amount of river sediments behind it. The coastline of the Rosetta promontory showed the highest erosion in the Delta with an average retreat rate of 137.4 m year- 1. In 1991, in an effort to mitigate sediment loss, a 4.85 km long seawall was built on the outer margin of the promontory. For additional beach protection, 15 groins were constructed along the eastern and western sides of the seawall in 2003 and 2005. To quantify erosion and accretion patterns along the Rosetta promontory, 11 Landsat images acquired at unequal intervals during a 40 year time span (1972 and 2012) were analyzed. The positions of shorelines were automatically extracted from satellite imagery and compared with three very high resolution QuickBird and WorldView2 images for data validation. Analysis of the rates of shoreline change revealed that the construction of the seawall was largely successful in halting the recession along the tip of the promontory, which lost 10.8 km2 prior to coastal protection. Conversely, the construction of the 15 groins has negatively affected the coastal morphology of the promontory and caused a reversal from accretion to fast erosion along the promontory leeside, where some segments of the shoreline have undergone as much as 30.8 m year- 1 of erosion. Without hard structures, the tip of the Rosetta promontory would have retreated 2.3 km by 2013 and lost 7.2 km2 of land. About 10% of this land is deltaic fertile cultivated farms. Moreover, without additional protection the sides of the promontory will lose about 1.3 km2 of land and the coastline would recede at an average rate of 200 m by 2020. Unless action is taken, coastal erosion, enhanced by rising sea level, will steadily eat away the Nile Delta at an alarming rate. The successful demonstration of the advocated procedures in this study could be

Tracking millennial-scale Holocene glacial advance and retreat using osmium isotopes: Insights from the Greenland ice sheet

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Rooney, Alan D.; Selby, David; Llyod, Jeremy M.; Roberts, David H.; Luckge, Andreas; Sageman, Bradley B.; Prouty, Nancy G.

2016-01-01

High-resolution Os isotope stratigraphy can aid in reconstructing Pleistocene ice sheet fluctuation and elucidating the role of local and regional weathering fluxes on the marine Os residence time. This paper presents new Os isotope data from ocean cores adjacent to the West Greenland ice sheet that have excellent chronological controls. Cores MSM-520 and DA00-06 represent distal to proximal sites adjacent to two West Greenland ice streams. Core MSM-520 has a steadily decreasing Os signal over the last 10 kyr (187Os/188Os = 1.35–0.81). In contrast, Os isotopes from core DA00-06 (proximal to the calving front of Jakobshavn Isbræ) highlight four stages of ice stream retreat and advance over the past 10 kyr (187Os/188Os = 2.31; 1.68; 2.09; 1.47). Our high-resolution chemostratigraphic records provide vital benchmarks for ice-sheet modelers as we attempt to better constrain the future response of major ice sheets to climate change. Variations in Os isotope composition from sediment and macro-algae (seaweed) sourced from regional and global settings serve to emphasize the overwhelming effect weathering sources have on seawater Os isotope composition. Further, these findings demonstrate that the residence time of Os is shorter than previous estimates of ∼104 yr.

Managed Retreat in New York after Sandy: Incentivizing Participation in High-Cost Areas

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McDonnell, S.; Ghorbani, P.; Wolf, C.; Stovall, G.

2017-12-01

Extreme weather events may potentially displace millions of people worldwide by 2100 (Nicholls et al., 2011). In the US, flood-prone areas are still attractive to many residents (Dyckman, St. John, & London, 2014), and the most common policies such as zoning or subsidized flood insurance continue to incentivize more development (Mechler & Bouwer, 2015). An increasingly popular alternative for mitigating flood damage is managed retreat, which consists of buying out properties in hazardous areas and relocating the owners elsewhere. We explore New York State's buyout program—a $680 million program administered under its Community Development Block Grant-Disaster Recovery (CDBG-DR) allocation—in the aftermath of Superstorm Sandy. Buyouts in New York tend to be costlier because of higher housing prices and density (Lincoln Institute, 2016), and potential participants may face challenges finding comparable housing within their communities. Since buyout offers are based on property values, homeowners with lower net property values may have less incentive to participate. We ask what neighborhood, household, and property characteristics affect the likelihood of participating in the buyout program. Specifically, are lower property values a disincentive to participation? We use binomial and multinomial logistic regression analyses to estimate the likelihood of participation for a sample of 2,062 properties invited to the program. Our main predictor compares the net offer amount against the local median housing value, controlling for an array of household and neighborhood characteristics. We find that relative property values are inversely correlated with participation, more visibly pronounced in areas with larger gaps between applicants' property values and local home values. While CDBG-DR is specifically geared towards lower-income families and neighborhoods, our findings imply that its existing structure may hinder engagement of these target groups in high-cost areas

Prevalence of post-traumatic stress symptoms and associated factors in tuberculosis (TB), TB retreatment and/or TB-HIV co-infected primary public health-care patients in three districts in South Africa.

Science.gov (United States)

Peltzer, Karl; Naidoo, Pamela; Matseke, Gladys; Louw, Julia; McHunu, Gugu; Tutshana, Bomkazi

2013-01-01

High rates of tuberculosis (TB) and TB/HIV co-infection is often linked with mental health issues such as post-traumatic stress disorder (PTSD) symptoms, which is further associated with poor health outcomes. In a country such as South Africa where rates of these infectious diseases are high, it is concerning that there is limited/no data on prevalence rates of mental disorders such as PTSD and its associated factors. Therefore, the aim of this study was to establish the prevalence of PTSD symptoms and associated factors in TB, TB retreatment and/or TB-HIV co-infected primary public health-care patients in three districts in South Africa. Brief screening self-report tools were used to measure: PTSD symptoms, psychological distress (anxiety and depression) and alcohol misuse. Other relevant measures, such as adherence to medication, stressful life events and sexual risk-taking behaviours, were obtained through structured questions. A total of 4900 public primary care adult patients from clinics in high TB burden districts from three provinces in South Africa participated. All the patients screened positive for TB (either new or retreatment cases). The prevalence of PTSD symptoms was 29.6%. Patients who screened positive for PTSD symptoms and psychological distress were more likely to be on antidepressant medication. Factors that predicted PTSD symptoms were poverty, residing in an urban area, psychological distress, suicide attempt, alcohol and/or drug use before sex, unprotected sex, TB-HIV co-infected and the number of other chronic conditions. Health-care systems should be strengthened to improve delivery of mental health care, by focusing on existing programmes and activities, such as those which address the prevention and treatment of TB and HIV.

Dating glacimarine sediments from the continental shelf in the Amundsen Sea using a multi-tool box: Implications for West Antarctic ice-sheet extent and retreat during the last glacial cycle

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Hillenbrand, C. D.; Smith, J.; Klages, J. P.; Kuhn, G.; Maher, B.; Moreton, S.; Wacker, L.; Frederichs, T.; Wiers, S.; Jernas, P.; Anderson, J. B.; Ehrmann, W. U.; Graham, A. G. C.; Gohl, K.; Larter, R. D.

2016-02-01

Satellite data and in-situ measurements show that today considerable mass loss is occurring from the Amundsen Sea sector of the West Antarctic Ice Sheet (WAIS). The observational record only spans the past four decades, and until recently the long-term context of the current deglaciation was poorly constrained. This information is, however, crucial for understanding WAIS dynamics, evaluating the role of forcing mechanisms for ice-sheet melting, and testing and calibrating ice-sheet models that attempt to predict future WAIS behavior and its impact on global sea level. Over the past decade several multinational marine expeditions and terrestrial fieldwork campaigns have targeted the Amundsen Sea shelf and its hinterland to reconstruct the WAIS configuration during the Last Glacial Maximum (LGM) and its subsequent deglacial history. The resulting studies succeeded in shedding light on the maximum WAIS extent at the LGM and the style, pattern and speed of its retreat and thinning thereafter. Despite this progress, however, significant uncertainties and discrepancies between marine and terrestrial reconstructions remain, which may arise from difficulties in dating sediment cores from the Antarctic shelf, especially their deglacial sections. Resolving these issues is crucial for understanding the WAIS' contribution to post-LGM sea-level rise, its sensitivity to different forcing mechanisms and its future evolution. Here we present chronological constraints on WAIS advance in the Amundsen Sea and its retreat from 20 ka BP into the Holocene that were obtained by various techniques, such as 14C dating of large ( 10 mg) and small (sample aliquots of calcareous microfossils, 14C dating of acid-insoluble organic matter combusted at low (300 °C) and high (800 °C) temperatures and dating of sediment cores by using geomagnetic paleointensity. We will compare the different age constraints and discuss their reliability, applicability and implications for WAIS history.

Effect of Exchanging Advancing and Retreating Side Materials on Mechanical Properties and Electrochemical Corrosion Resistance of Dissimilar 6013-T4 and 7003 Aluminum Alloys FSW Joints

Science.gov (United States)

Zhao, Zhixia; Liang, Haimei; Zhao, Yong; Yan, Keng

2018-03-01

Friction stir welding (FSW) was used to weld dissimilar joints between Al 6013-T4 and Al7003 alloys in this work. The effect of exchanging advancing (AS) and retreating (RS) side material on microstructure, mechanical behaviors and electrochemical corrosion resistance was discussed. Results showed that different joint cross sections were obtained when exchanging AS and RS materials. The material on the AS would be more deformed during the welding process. When the Al6013 placed on the AS, the plastic flow of weld is more sufficient. Whether on the AS or RS, the Al6013-T4 side is the weak region for both tensile specimens and hardness samples. The fracture position corresponds to the minimum hardness position. Also, more strengthening phase can be retained in the joint, and the joint of A6R7 has better corrosion resistance.

SU-F-T-626: Intracranial SRS Re-Treatment Without Acquisition of New CT Images

International Nuclear Information System (INIS)

Wiant, D; Manning, M; Liu, H; Maurer, J; Hayes, T; Sintay, B

2016-01-01

Purpose: Linear accelerator based stereotactic radiosurgery (SRS) for multiple intracranial lesions with frequent surveillance is becoming a popular treatment option. This strategy leads to retreatment with SRS as new lesions arise. Currently, each course of treatment uses magnetic resonance (MR) and computed tomography (CT) images for treatment planning. We propose that new MR images, with course 1 CT images, may be used for future treatment plans with negligible loss of dosimetric accuracy. Methods: Ten patients that received multiple courses of SRS were retrospectively reviewed. The treatment plans and contours from non-initial courses were copied to the initial CTs and recalculated. Doses metrics for the plans calculated on the initial CTs and later CTs were compared. All CT scans were acquired on a Philips CT scanner with a 600 mm field of view and 1 mm slice thickness (Philips Healthcare, Andover, MA). All targets were planned to 20 Gy and calculated in Eclipse V. 13.6 (Varian, Palo Alto, CA) using analytic anisotropic algorithm with 1 mm calculation grid. Results: Sixteen lesions were evaluated. The mean time between courses was 250 +/− 215 days (range 103–979). The mean target volume was 2.0 +/− 2.9 cc (range 0.1–10.1). The average difference in mean target dose between the two calculations was 0.2 +/− 0.3 Gy (range 0.0 – 1.0). The mean conformity index (CI) was 1.28 +/− 0.14 (range 1.07 – 1.82). The average difference in CI was 0.03 +/− 0.16 (range 0.00 – 0.44). Targets volumes < 0.5 cc showed the largest changes in both metrics. Conclusion: Continued treatment based on initial CT images is feasible. Dose calculation on the initial CT for future treatments provides reasonable dosimetric accuracy. Changes in dose metrics are largest for small volumes, and are likely dominated by partial volume effects in target definition.

Sea Ice Retreat and its Impact on the Intensity of Open-Ocean Convection in the Greenland and Iceland Seas

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Moore, K.; Våge, K.; Pickart, R. S.; Renfrew, I.

2016-12-01

The air-sea transfer of heat and freshwater plays a critical role in the global climate system. This is particularly true for the Greenland and Iceland Seas, where these fluxes drive ocean convection that contributes to Denmark Strait Overflow Water, the densest component of the lower limb of the Atlantic Meridional Overturning Circulation (AMOC). This buoyancy transfer is most pronounced during the winter downstream of the ice edge, where the cold and dry Arctic air first comes in contact with the relatively warm ocean surface. Here we show that the wintertime retreat of sea ice in the region, combined with different rates of warming for the atmosphere and sea surface of the Greenland and Iceland Seas, has resulted in statistically significant reductions of approximately 20% in the magnitude of the winter air-sea heat fluxes since 1979. Furthermore, it is demonstrated that modes of climate variability other than the North Atlantic Oscillation (NAO) are required to fully characterize the regional air-sea interaction in this region. Mixed-layer model simulations imply that a continued decrease in atmospheric forcing will exceed a threshold for the Greenland Sea whereby convection will become depth limited, reducing the ventilation of mid-depth waters in the Nordic Seas. In the Iceland Sea, further reductions have the potential to decrease the supply of the densest overflow waters to the AMOC.

Changes in Hydrologic Conditions and Greenhouse Gas Emissions in Circumpolar Regions due to Climate Change Induced Permafrost Retreat

Energy Technology Data Exchange (ETDEWEB)

Whiticar, M. J. [School of Earth and Ocean Sciences, University of Victoria, Victoria (Canada); Bhatti, J.; Startsev, N. [Northern Forestry Centre, St Edmonton, AB (Canada)

2013-07-15

Thawing permafrost peatlands substantially influence Canadian northern ecosystems by changing the regional hydrology and mobilizing the vast carbon (C) reserves that results in increased greenhouse gas (GHGs) emissions to the atmosphere. With permafrost distribution controlled largely by topography and climate, our International polar y ear (IPY) study intensively monitored the local C cycling processes and GHG fluxes associated with different hydrologic and permafrost environments at 4 sites along a climatic gradient extending from the Isolated patches permafrost Zone (northern alberta), to the continuous permafrost Zone (Inuvik, NWT). Each site encompasses a local gradient from upland forest and peat plateau to collapse scar. Our multi-year measurements of peatland profiles and flux chambers for CH{sub 4} and CO{sub 2} concentrations and stable isotope ratios indicate processes, including methanogenesis, methanotrophy, transport and emission that control the distribution of these GHGs. These relationships are modulated by fluctuating local soil water and corresponding ecosystem conditions. The gas geochemistry shows that significant surface CH{sub 4} production occurs by both hydrogenotrophic and acetoclastic methanogenesis in submerged, anaerobic peats, e.g., collapse scars, whereas methane oxidation is restricted to aerobic, drier environments, e.g., upland sites and peat-atmosphere interface. The most active methanogenesis and emissions are in areas of actively thawing permafrost contrasting with sites under continuous permafrost. This degree of methanogenesis is being amplified by the increased rate of Arctic warming and the rapid retreat of permafrost in canada's arctic (approximately. 2.5 km/a). (author)

Retreatment of Chronic Hepatitis C Infection with Telaprevir: Preliminary Results in Turkey

Directory of Open Access Journals (Sweden)

Orhan Yıldız

2015-09-01

Full Text Available Background: The use of pegylated interferon alpha and ribavirin (PegIFN/RBV for the retreatment of chronic hepatitis C virus (HCV infection without a sustained virological response (SVR prior to PegIFN/RBV treatment has resulted in low success rates. Aims: To investigate the efficacy and safety of telaprevir (TVR in combination with PegIFN/RBV in patients infected with HCV genotypes 1 and 4 who were previously treated with PegIFN/RBV and failed to achieve SVR. Study Design: Multi-center, retrospective, cross-sectional study. Methods: The study included 111 patients: 80 prior relapsers, 25 prior null responders, and six prior partial responders to PegIFN/RBV treatment. The patients were given TVR/PegIFN/RBV for 12 weeks, followed by a 12-week PegIFN/RBV treatment; virological response results were assessed at weeks 4, 12, and 24. Treatment was discontinued in patients with HCV RNA >1000 IU/mL at week 4 or with negative RNA results at week 4 but >1000 IU/mL at week 12. Rapid virological response (RVR, early virological response (EVR, extended rapid virological response (eRVR, and virological response at 24th week of treatment were evaluated. The side effects of combination therapy and the rates of treatment discontinuation were investigated. Results: The mean age of the patients was 56.02±9.96 years and 45.9% were male. Ninety-one percent of the patients were infected with viral genotype 1, 69.6% with the interleukin (IL 28B genotype CT and 20.2% were cirrhotic. The RVR rate was 86.3% in prior relapsers, 56% in prior null responders, and 50% in prior partial responders (p=0.002. EVR rates in those groups were 91.3%, 56%, and 83.3%, respectively (p<0.001. eRVR rates were 83.8% in prior relapsers, 48% in prior null responders, and 50% in prior partial responders (<0.001. The virological response at the 24th week of treatment was found to be the highest in prior relapsers (88.8%; it was 56% in prior null responders and 66.7% in prior partial

Investigating the Impact of Ecological Succession on Fluxes of Halogenated Volatile Organic Compounds (HVOCs) from Retreating Glacier Forefields

Science.gov (United States)

Macdonald, M.; Young, D.; O'Doherty, S.; Wadham, J.

2017-12-01

The Arctic is one of the fastest warming regions of the Earth, with temperature increases of +7oC projected by 2100 under a mitigation emission scenario. These climate perturbations are forecast to cause the retreat of extensive glacial systems across Canada, Greenland, Svalbard and the Russian Arctic. This will reveal new proglacial land surfaces for microbial colonisation, ultimately succeeding to tundra over decades to centuries. A relatively unexplored dimension to these changes is their impact upon the emission and consumption of halogenated volatile organic compounds (HVOCs) from proglacial land surfaces. HVOCs are involved in several important atmospheric processes such as ozone destruction and aerosol formation and despite considerable research, uncertainties remain in the natural cycles of some of these compounds. Here, we investigated the influence of biological process on the fluxes of HVOCs from recently (chambers on surfaces spanning recently-exposed sediments, to approx. 100 yr old tundra in front of Midtre Lovenbreen glacier, Svalbard. In-field analysis of a suite of HVOCs was conducted using a GCMS (gas chromatograph mass spectrometer) with a custom-built pre-concentration system. HVOC concentrations were evaluated with reference to biological (e.g. cell numbers) and physio-chemical (e.g. water content) parameters of the land surface, in order to assess the importance of the microbial community on the net flux. Significant rates of consumption of some HVOC species and production of others was detected. Further laboratory incubations supported the findings in the field. Proglacial surfaces are, therefore, a previously unrecognised sink and source of various HVOCs that have the potential to increase in importance with projected future climate change.

Lake sediment-based Late Holocene glacier reconstruction reveals medieval retreat and two-phase Little Ice Age on subantarctic South Georgia

Science.gov (United States)

van der Bilt, W. G. M.; Bakke, J.; Werner, J.; Paasche, O.; Rosqvist, G. N.; Vatle, S. S.

2016-12-01

Southern Ocean climate is rapidly changing. Yet beyond the instrumental period (± 100 years), our comprehension of climate variability in the region is restricted by a lack of high-resolution paleoclimate records. Alpine glaciers, ubiquitous on Southern Ocean islands, may provide such data as they rapidly respond to climate shifts, recording attendant changes in extent by variations in glacial erosion. Rock flour, the fine-grained fraction of this process, is suspended in meltwater streams and transfers this signal to the sediments of downstream lakes, continuously recording glacier history. Here, we use this relationship and present the first reconstruction of the Late Holocene (1250 cal. yr BP - present) glacier history of the Southern Ocean island of South Georgia, using sediments from the glacier-fed Middle Hamberg lake. Variations are resolved on multi-centennial scales due to robust chronological control. To fingerprint a glacial erosion signal, we employed a set of routinely used physical, geochemical and magnetic parameters. Using Titanium counts, validated against changes in sediment density and grain size distribution, we continuously reconstruct glacier variations over the past millennium. Refining local moraine evidence and supporting evidence from other Southern Hemisphere sites, this study shows a progressive diminishing of consecutive Late Holocene advances. These include a two-stage Little Ice Age, in agreement with other Southern Hemisphere glacier evidence. The presented record furthermore captures an unreported retreat phase behind present limits around 500 cal. yr BP.

Deglacial to Holocene history of ice-sheet retreat and bottom current strength on the western Barents Sea shelf

Science.gov (United States)

Lantzsch, Hendrik; Hanebuth, Till J. J.; Horry, Jan; Grave, Marina; Rebesco, Michele; Schwenk, Tilmann

2017-10-01

High-resolution sediment echosounder data combined with radiocarbon-dated sediment cores allowed us to reconstruct the Late Quaternary stratigraphic architecture of the Kveithola Trough and surrounding Spitsbergenbanken. The deposits display the successive deglacial retreat of the Svalbard-Barents Sea Ice Sheet. Basal subglacial till indicates that the grounded ice sheet covered both bank and trough during the Late Weichselian. A glaciomarine blanket inside the trough coinciding with laminated plumites on the bank formed during the initial ice-melting phase from at least 16.1 to 13.5 cal ka BP in close proximity to the ice margin. After the establishment of open-marine conditions at around 13.5 cal ka BP, a sediment drift developed in the confined setting of the Kveithola Trough, contemporary with crudely laminated mud, an overlying lag deposit, and modern bioclastic-rich sand on Spitsbergenbanken. The Kveithola Drift shows a remarkable grain-size coarsening from the moat towards the southern flank of the trough. This trend contradicts the concept of a separated drift (which would imply coarser grain sizes in proximity of the moat) and indicates that the southern bank is the main sediment source for the coarse material building up the Kveithola Drift. This depocenter represents, therefore, a yet undescribed combination of off-bank wedge and confined drift. Although the deposits inside Kveithola Trough and on Spitsbergenbanken display different depocenter geometries, time-equivalent grain-size changes imply a region-wide sediment-dynamic connection. We thus relate a phase of coarsest sediment supply (8.8-6.3 cal ka BP) to an increase in bottom current strength, which might be related to a stronger Atlantic Water inflow from the Southeast across the bank leading to winnowing and off-bank export of sandy sediments.

Proposal of early retreatment with iloprost in partially responsive patients with bone marrow edema syndrome: a case report

Directory of Open Access Journals (Sweden)

Simone Meini

2012-12-01

Full Text Available Background Avascular Necrosis (AVN is defined as the cellular death of bone components due to an alteration of the blood supply, resulting in Edema of the Bone Marrow (BME, structural collapse and bone destruction. In advanced stages, AVN requires surgery. One emerging medical treatment for supporting osseous perfusion is the administration of iloprost.Materials and methods A 38-year-old woman presented with severe BME of the left hip (primary, persisting for 6 weeks. She was treated with iloprost iv at 2 ng/kg/min for 6 hours/day for 5 days, and after 4 weeks, the treatment was repeated at 1.5 ng/kg/min for 6 hours for 5 days because she exhibited only a partial response to the first treatment. Complete remission was obtained, documented clinically and on Magnetic Resonance Imaging (MRI. Her Harris Hip Score (HHS increased from 29.90 to 97. No significant adverse events related to iloprost were registered. No surgical procedures were necessary.Conclusions In most cases, iloprost is administered in a single cycle of treatment over 5 days at 1-2 ng/kg/min for 6 hours/day, but no research has investigated the effectiveness of early retreatment after the first cycle results in only a partially response. Only a few studies examining small numbers of patients have evaluated iloprost in AVN/BME, preferring, in most cases, the dose of 1 ng/kg/min and obtaining clinical improvement both in BME and in AVN in times comparable to surgical core decompression. This case report demonstrates the safety and effectiveness of early repetition of the maximal dose of iloprost before BME evolves into AVN, as well as in cases initially appearing serious and requiring surgical procedures.

Heat release, time required, and cleaning ability of MTwo R and ProTaper universal retreatment systems in the removal of filling material.

Science.gov (United States)

Bramante, Clovis Monteiro; Fidelis, Natasha Siqueira; Assumpção, Tatiana Santos; Bernardineli, Norberti; Garcia, Roberto Brandão; Bramante, Alexandre Silva; de Moraes, Ivaldo Gomes

2010-11-01

This ex vivo study evaluated the heat release, time required, and cleaning efficacy of MTwo (VDW, Munich, Germany) and ProTaper Universal Retreatment systems (Dentsply/Maillefer, Ballaigues, Switzerland) and hand instrumentation in the removal of filling material. Sixty single-rooted human teeth with a single straight canal were obturated with gutta-percha and zinc oxide and eugenol-based cement and randomly allocated to 3 groups (n = 20). After 30-day storage at 37 °C and 100% humidity, the root fillings were removed using ProTaper UR, MTwo R, or hand files. Heat release, time required, and cleaning efficacy data were analyzed statistically (analysis of variance and the Tukey test, α = 0.05). None of the techniques removed the root fillings completely. Filling material removal with ProTaper UR was faster but caused more heat release. Mtwo R produced less heat release than the other techniques but was the least efficient in removing gutta-percha/sealer. ProTaper UR and MTwo R caused the greatest and lowest temperature increase on root surface, respectively; regardless of the type of instrument, more heat was released in the cervical third. Pro Taper UR needed less time to remove fillings than MTwo R. All techniques left filling debris in the root canals. Copyright © 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

The water erosion processes in the retreat erosive of cliff on soft rocks in the province of Cadiz (Spain); Los procesos de erosion hidrica en el retroceso erosivo de acantilados sobre rocas blandas en la provincia de Cadiz

Energy Technology Data Exchange (ETDEWEB)

Rendon Aragon, J. J.; Gracia Prieto, F. J.; Rio Rodriguez, L. del

2009-07-01

The littoral cliffs on soft materials of the Atlantic Cadiz coast show an important activity of the fresh water erosion processes, sometimes even more significant than the marine erosion processes. The connection of the lower cliffs with sandy beaches favours aeolian sand invasion, which fills previous rills and reduces the water erosion intensity by increasing infiltration. Cliff retreat and rill erosion measurement by using erosion sticks has shown very variables values, most of them higher than the estimated error of the employed methods. This indicates the existence of other factors influencing the distribution of water erosion processes along these cliffs, which have to be studied through different techniques. (Author) 5 refs.

Clinical Response to Gefitinib Retreatment of Lung Adenocarcinoma Patients Who Benefited from An Initial Gefitinib Therapy: A Retrospective Analysis

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Junling LI

2012-01-01

Full Text Available Background and objective Gefitinib is an epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI that has been widely used for the treatment of non-small cell lung cancer (NSCLC. It is most effective in women, as well as in patients who have never smoked, have pulmonary adenocarcinomas, or are of Asian origin. Several treatment options are available for NSCLC patients who responded to initial gefitinib therapy but demonstrated tumor progression, of which gefitinib readministration is the chosen therapeutic option. The present study aims to evaluate the efficacy and toxicity of gefitinib readministration. Methods The clinical data of 18 patients with NSCLC who had shown partial response (PR or achieved a stable disease (SD status after gefitinib administration and were retreated with gefitinib due to failure of the initial therapy were reviewed and retrospectively analyzed. Results Of the 18 patients studied, 1 (6% showed partial remission (PR, 11 (61% achieved SD, and 6 (33% experienced disease progression. The disease control rate was 67%, and the median progression-free survival was 5.16 months (range, 1 to 24.8 months. The median overall survival from the start of the gefitinib therapy was 39.4 months (range, 15.38 to 52.44 months. Moreover, the median overall survival from the beginning of the 2nd therapy was 12.41 months (range, 3.98 to 38.24 months. Mild toxicity was observed with the 2nd gefitinib therapy. Conclusion The results of the present study indicate that patients with NSCLC may still be expected to achieve prolonged survival through gefitinib readministration if they initially responded to gefitinib and underwent various subsequent treatments.

Comparison of three retreatment techniques with ultrasonic activation in flattened canals using micro-computed tomography and scanning electron microscopy.

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Bernardes, R A; Duarte, M A H; Vivan, R R; Alcalde, M P; Vasconcelos, B C; Bramante, C M

2015-08-17

To use micro-CT to quantitatively evaluate the amount of residual filling material after using several techniques to remove root fillings with and without ultrasonic activation and to analyse the cleanliness of the root canal walls and dentine tubules with scanning electron microscopy (SEM). The root canals of one hundred and eight human mandibular incisors were selected and instrumented with rotary files using the BioRace system up to file size 40, .04 taper. After instrumentation, the teeth were filled using a hybrid technique with gutta-percha and sealer then divided into three groups according to the method used for removing the root filling: G1-Reciproc (using only instrument R50), G2-ProTaper Universal retreatment system and G3-Manual (hand files and Gates-Glidden burs). All groups were divided into two subgroups depending on whether ultrasonic agitation was used with the irrigants. Micro-CT scans were taken before and after removal of the filling material to detect residual material in the canal. After micro-CT analysis, the roots were cut in half, imaged by SEM and scored based on the amount of surface covered by root filling remnants. The data were analysed statistically using a significance level of 5%. All groups had retained material in the root canals after instrumentation. The Reciproc method was associated with less retained material than the ProTaper and Manual methods. Ultrasonic activation significantly reduced the amount of residual root filling in all groups (P material. Ultrasonic activation improved the removal of root filling material in all groups. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Phased occupation and retreat of the last British-Irish Ice Sheet in the southern North Sea; geomorphic and seismostratigraphic evidence of a dynamic ice lobe

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Dove, Dayton; Evans, David J. A.; Lee, Jonathan R.; Roberts, David H.; Tappin, David R.; Mellett, Claire L.; Long, David; Callard, S. Louise

2017-05-01

Along the terrestrial margin of the southern North Sea, previous studies of the MIS 2 glaciation impacting eastern Britain have played a significant role in the development of principles relating to ice sheet dynamics (e.g. deformable beds), and the practice of reconstructing the style, timing, and spatial configuration of palaeo-ice sheets. These detailed terrestrially-based findings have however relied on observations made from only the outer edges of the former ice mass, as the North Sea Lobe (NSL) of the British-Irish Ice Sheet (BIIS) occupied an area that is now almost entirely submarine (c.21-15 ka). Compounded by the fact that marine-acquired data have been primarily of insufficient quality and density, the configuration and behaviour of the last BIIS in the southern North Sea remains surprisingly poorly constrained. This paper presents analysis of a new, integrated set of extensive seabed geomorphological and seismo-stratigraphic observations that both advances the principles developed previously onshore (e.g. multiple advance and retreat cycles), and provides a more detailed and accurate reconstruction of the BIIS at its southern-most extent in the North Sea. A new bathymetry compilation of the region reveals a series of broad sedimentary wedges and associated moraines that represent several terminal positions of the NSL. These former still-stand ice margins (1-4) are also found to relate to newly-identified architectural patterns (shallow stacked sedimentary wedges) in the region's seismic stratigraphy (previously mapped singularly as the Bolders Bank Formation). With ground-truthing constraint provided by sediment cores, these wedges are interpreted as sub-marginal till wedges, formed by complex subglacial accretionary processes that resulted in till thickening towards the former ice-sheet margins. The newly sub-divided shallow seismic stratigraphy (at least five units) also provides an indication of the relative event chronology of the NSL. While there

Neoglacial Antarctic sea-ice expansion driven by mid-Holocene retreat of the Ross Ice Shelf.

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Bendle, J. A.; Newton, K.; Mckay, R. M.; Crosta, X.; Etourneau, J.; Anya, A. B.; Seki, O.; Golledge, N. R.; Bertler, N. A. N.; Willmott, V.; Schouten, S.; Riesselman, C. R.; Masse, G.; Dunbar, R. B.

2017-12-01

Recent decades have seen expanding Antarctic sea-ice coverage, coeval with thinning West Antarctic Ice Sheet (WAIS) ice shelves and the rapid freshening of surface and bottom waters along the Antarctic margin. The mid-Holocene Neoglacial transition represents the last comparable baseline shift in sea-ice behaviour. The drivers and feedbacks involved in both the recent and Holocene events are poorly understood and characterised by large proxy-model mismatches. We present new records of compound specific fatty acid isotope analyses (δ2H-FA), highly-branched isoprenoid alkenes (HBIs) TEX86L temperatures, grain-size, mass accumulations rates (MARs) and image analyses from a 171m Holocene sediment sequence from Site U1357 (IODP leg 318). In combination with published records we reconstruct Holocene changes in glacial meltwater, sedimentary inputs and sea-ice. The early Holocene (11 to 10 ka) is characterised by large fluctuations in inputs of deglacial meltwater and sediments and seismic evidence of downlapping material from the south, suggesting a dominating influence from glacial retreat of the local outlet glaciers. From 10 to 8 ka there is decreasing meltwater inputs, an onlapping drift and advection of material from the east. After ca. 8 ka positively correlated δ2H-FA and MARs infer that pulses of glacial melt correlate to stronger easterly currents, driving erosion of material from upstream banks and that the Ross Ice Shelf (RIS) becomes a major influence. A large mid-Holocene meltwater pulse (preceded by warming TEX86L temperatures) is evident between ca. 6 to 4.5 ka, culminating in a rapid and permanent increase in sea-ice from 4.5 ka. This is coeval with cosmogenic nuclide evidence for a rapid thinning of the Antarctic ice sheet during the mid-Holocene (Hein et al., 2016). We suggest this represents a final major pulse of deglaciation from the Ross Ice Shelf, which initiates the Neoglacial, driving cool surface waters along the coast and greater sea

AHP 47: THE PROVOCATIVE RABBIT

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Rnam rgyal རྣམ་རྒྱལ།

2017-04-01

Full Text Available A retreatant finished chanting for a family, packed up the offerings from the host, and started back to his hermitage feeling satisfied. A rabbit, called Ja dkrug mgo 'Trouble Maker', watched the retreatant through an evergreen bush, and decided he wanted to cheat the retreatant out of his offerings. Trouble Maker came out of the bush and stood in front of the retreatant in the middle of the path. As the retreatant came closer, Trouble Maker ran forward a few steps and then again turned back to watch the retreatant, who chased the rabbit for a while, but the heavy bag burdened him and he soon got very tired. He finally threw down his bag and chased Trouble Maker, who ran just beyond the retreatant’s grasp. Finally, having left the retreatant far behind, Trouble Maker doubled back, picked up the retreatant's bag, and carried it off. ...

Reconciling records of ice streaming and ice margin retreat to produce a palaeogeographic reconstruction of the deglaciation of the Laurentide Ice Sheet

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Margold, Martin; Stokes, Chris R.; Clark, Chris D.

2018-06-01

This paper reconstructs the deglaciation of the Laurentide Ice Sheet (LIS; including the Innuitian Ice Sheet) from the Last Glacial Maximum (LGM), with a particular focus on the spatial and temporal variations in ice streaming and the associated changes in flow patterns and ice divides. We build on a recent inventory of Laurentide ice streams and use an existing ice margin chronology to produce the first detailed transient reconstruction of the ice stream drainage network in the LIS, which we depict in a series of palaeogeographic maps. Results show that the drainage network at the LGM was similar to modern-day Antarctica. The majority of the ice streams were marine terminating and topographically-controlled and many of these continued to function late into the deglaciation, until the ice sheet lost its marine margin. Ice streams with a terrestrial ice margin in the west and south were more transient and ice flow directions changed with the build-up, peak-phase and collapse of the Cordilleran-Laurentide ice saddle. The south-eastern marine margin in Atlantic Canada started to retreat relatively early and some of the ice streams in this region switched off at or shortly after the LGM. In contrast, the ice streams draining towards the north-western and north-eastern marine margins in the Beaufort Sea and in Baffin Bay appear to have remained stable throughout most of the Late Glacial, and some of them continued to function until after the Younger Dryas (YD). The YD influenced the dynamics of the deglaciation, but there remains uncertainty about the response of the ice sheet in several sectors. We tentatively ascribe the switching-on of some major ice streams during this period (e.g. M'Clintock Channel Ice Stream at the north-west margin), but for other large ice streams whose timing partially overlaps with the YD, the drivers are less clear and ice-dynamical processes, rather than effects of climate and surface mass balance are viewed as more likely drivers. Retreat

Lateglacial geomorphology in the Tweedsmuir Hills, Scotland - Implications for retreat patterns, glacier reconstruction and chronology.

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Pearce, D.; Rea, B.; McDougall, D.

2012-04-01

Lateglacial landform assemblage indicates more extensive glaciation than previously envisaged, with both a transection ice-mass and icefield coexisting, reflecting different topographic controls. Interestingly, a geomorphic pattern is observable in more than one valley, which is interpreted as a synchronous recession of the outlet glaciers and a rapid deglaciation towards the summits. Whilst two landsystems have been mapped the second poses interesting problems regarding extent and timing of glaciation. The Loch Skene site has been traditionally associated with a small valley glacier. However, it appears to feed ice into a lower valley which exhibits a landform assemblage typical of Lateglacial deglaciation in Scotland. It is tentatively proposed that the Loch Skene glacier represents a retreat phase prior to complete deglaciation rather than the Younger Dryas maximum.

Tropical tales of polar ice: evidence of Last Interglacial polar ice sheet retreat recorded by fossil reefs of the granitic Seychelles islands

Science.gov (United States)

Dutton, Andrea; Webster, Jody M.; Zwartz, Dan; Lambeck, Kurt; Wohlfarth, Barbara

2015-01-01

In the search for a record of eustatic sea level change on glacial-interglacial timescales, the Seychelles ranks as one of the best places on the planet to study. Owing to its location with respect to the former margins of Northern Hemisphere ice sheets that wax and wane on orbital cycles, the local-or relative-sea level history is predicted to lie within a few meters of the globally averaged eustatic signal during the Last Interglacial period. We have surveyed and dated Last Interglacial fossil corals to ascertain peak sea level and hence infer maximum retreat of polar ice sheets during this time interval. We observe a pattern of gradually rising sea level in the Seychelles between ˜129 and 125 thousand years ago (ka), with peak eustatic sea level attained after 125 ka at 7.6 ± 1.7 m higher than present. After accounting for thermal expansion and loss of mountain glaciers, this sea-level budget would require ˜5-8 m of polar ice sheet contribution, relative to today's volume, of which only ˜2 m came from the Greenland ice sheet. This result clearly identifies the Antarctic ice sheet as a significant source of melt water, most likely derived from one of the unstable, marine-based sectors in the West and/or East Antarctic ice sheet. Furthermore, the establishment of a +5.9 ± 1.7 m eustatic sea level position by 128.6 ± 0.8 ka would require that partial AIS collapse was coincident with the onset of the sea level highstand.

RETRATAMENTO ENDODÔNTICO: ESTUDO COMPARATIVO ENTRE TÉCNICA MANUAL, ULTRA-SOM E CANAL FINDER ENDODONTIC RETREATMENT: COMPARATIVE STUDY BETWEEN MANUAL TECHNIQUE, ULTRASONIC SCALER, AND CANAL FINDER

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Clovis Monteiro BRAMANTE

1998-01-01

Full Text Available Instrumentações manual, ultra-sônica e com Canal Finder foram utilizadas para retratamento de 30 dentes com canais obturados com guta-percha e óxido de zinco e eugenol. Avaliaram-se: 1. tempo gasto para a penetração inicial até o ápice; 2. tempo para completar a limpeza; 3. extrusão de material e 4. limpeza dos canais. O Canal Finder foi a técnica que propiciou melhor limpeza, seguida da manual e da ultra-sônica. A parede palatina do canal foi constantemente mais limpa do que a vestibular. Quanto à extrusão, a técnica de ultra-som foi a que propiciou mais extravasamento de material obturador.Endodontic retreatment of 30 teeth filled with guta percha and zinc oxide-eugenol was carried out using manual instrumentation, ultrasonic scaler, and the Canal Finder System. The following variables were evaluated: time spent to reach the apex; time spent to complete cleaning of the canal; apical extrusion of material; and cleanliness of the canals. Results showed the Canal Finder System as providing the highest level of cleanliness of the canal system; lingual walls were constantly cleaner than buccal walls; ultrasonic technique presented a greater degree of apical extrusion of filling material.

Impacts of sea ice retreat, thinning, and melt-pond proliferation on the summer phytoplankton bloom in the Chukchi Sea, Arctic Ocean

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Palmer, Molly A.; Saenz, Benjamin T.; Arrigo, Kevin R.

2014-07-01

In 2011, a massive phytoplankton bloom was observed in the Chukchi Sea under first-year sea ice (FYI), an environment in which primary productivity (PP) has historically been low. In this paper, we use a 1-D biological model of the Chukchi shelf ecosystem, in conjunction with in situ chemical and physiological data, to better understand the conditions that facilitated the development of such an unprecedented bloom. In addition, to assess the effects of changing Arctic environmental conditions on net PP (NPP), we perform model runs with varying sea ice and snow thickness, timing of melt, melt ponds, and biological parameters. Results from model runs with conditions similar to 2011 indicate that first-year ice (FYI) with at least 10% melt pond coverage transmits sufficient light to support the growth of shade-adapted Arctic phytoplankton. Increasing pond fraction by 20% enhanced peak under-ice NPP by 26% and produced rates more comparable to those measured during the 2011 bloom, but there was no effect of further increasing pond fraction. One of the important consequences of large under-ice blooms is that they consume a substantial fraction of surface nutrients such that NPP is greatly diminished in the marginal ice zone (MIZ) following ice retreat, where NPP has historically been the highest. In contrast, in model runs with ultraviolet radiation and zooplankton grazers reduce peak open water NPP but have little impact on under-ice NPP, which has important implications for the relative proportion of NPP concentrated in pelagic vs. benthic food webs. Finally, the shift in the relative amount of NPP occurring in under-ice vs. open-water environments may affect total ecosystem productivity.

Large-scale glacitectonic deformation in response to active ice sheet retreat across Dogger Bank (southern central North Sea) during the Last Glacial Maximum

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Phillips, Emrys; Cotterill, Carol; Johnson, Kirstin; Crombie, Kirstin; James, Leo; Carr, Simon; Ruiter, Astrid

2018-01-01

High resolution seismic data from the Dogger Bank in the central southern North Sea has revealed that the Dogger Bank Formation records a complex history of sedimentation and penecontemporaneous, large-scale, ice-marginal to proglacial glacitectonic deformation. These processes led to the development of a large thrust-block moraine complex which is buried beneath a thin sequence of Holocene sediments. This buried glacitectonic landsystem comprises a series of elongate, arcuate moraine ridges (200 m up to > 15 km across; over 40-50 km long) separated by low-lying ice marginal to proglacial sedimentary basins and/or meltwater channels, preserving the shape of the margin of this former ice sheet. The moraines are composed of highly deformed (folded and thrust) Dogger Bank Formation with the lower boundary of the deformed sequence (up to 40-50 m thick) being marked by a laterally extensive décollement. The ice-distal parts of the thrust moraine complex are interpreted as a "forward" propagating imbricate thrust stack developed in response to S/SE-directed ice-push. The more complex folding and thrusting within the more ice-proximal parts of the thrust-block moraines record the accretion of thrust slices of highly deformed sediment as the ice repeatedly reoccupied this ice marginal position. Consequently, the internal structure of the Dogger Bank thrust-moraine complexes can be directly related to ice sheet dynamics, recording the former positions of a highly dynamic, oscillating Weichselian ice sheet margin as it retreated northwards at the end of the Last Glacial Maximum.

Management of recurrent stress urinary incontinence after burch and sling procedures.

Science.gov (United States)

Zimmern, Philippe E; Gormley, E Ann; Stoddard, Anne M; Lukacz, Emily S; Sirls, Larry; Brubaker, Linda; Norton, Peggy; Oliphant, Sallie S; Wilson, Tracey

2016-03-01

To examine treatment options selected for recurrent stress urinary incontinence (rSUI) in follow-up after Burch, autologous fascial and synthetic midurethral sling (MUS) procedures. We performed a secondary analysis of the SISTER and ToMUS trials of participants who underwent primary stress urinary incontinence (SUI) treatment (without prior SUI surgery or concomitant procedures). Using Kaplan-Meier analysis, retreatment-free survival rates by initial surgical procedure were compared. Mean MESA (Medical Epidemiologic and Social Aspects of Aging) stress index was also compared between those retreated for rSUI compared to those not retreated. Half of the women in the SISTEr trial met inclusion criteria for this analysis (329/655, 174 Burch and 155 fascial sling), as did 444/597 (74%) of subjects in ToMUS (221 transobturator midurethral sling (TMUS), and 223 retropubic midurethral sling (RMUS). Types of surgical retreatment included autologous fascial sling (19), synthetic sling (1), and bulking agent (18). Five-year retreatment free survival rates (and standard errors) were 87% (3%), 96% (2%), 97% (1%), and 99% (0.7%) for Burch, autologous fascial sling, TMUS, and RMUS groups respectively (P < 0.0001). For all index surgery groups, the mean MESA stress index at last visit prior to retreatment for those retreated (n = 23) was significantly higher than mean MESA stress index at last visit for those not retreated (n = 645) (P < 0.0001). In these cohorts, 6% of women after standard anti-incontinence procedures were retreated within 5 years, mostly with injection therapy or autologous fascial sling. Not all women with rSUI chose surgical retreatment. © 2015 Wiley Periodicals, Inc.

Trauma to an implant-supported crown that was saved by the fixation screw : A case report

NARCIS (Netherlands)

den Hartog, Laurens; Meijer, Henny J. A.; Stellingsma, Kees; Santing, Hendrik J.; Raghoebar, Gerry M.

A traumatic impact to an implant-supported crown might damage the implant, restoration and peri-implant tissues. Ideally, only a small prosthetic retreatment is needed for restoration, as complicated prosthetic retreatments or surgical retreatments in particular, could be very inconvenient for the

Teambuilding and leadership training in an internal medicine residency training program.

Science.gov (United States)

Stoller, James K; Rose, Mark; Lee, Rita; Dolgan, Colleen; Hoogwerf, Byron J

2004-06-01

The purpose of this report is to describe and evaluate the impact of a 1-day retreat focused on developing leadership skills and teambuilding among postgraduate year 1 residents in an internal medicine residency. A group of organizers, including members of the staff, the chief medical residents, administrative individuals in the residency office, and an internal organizational development consultant convened to organize an off-site retreat with activities that would provide experiential learning regarding teamwork and leadership, including a "reef survival exercise" and table discussions regarding the characteristics of ideal leaders. In addition, several energizing activities and recreational free time was provided to enhance the interaction and teamwork dimensions of the retreat. To evaluate the impact of the retreat, attendees completed baseline and follow-up questionnaires regarding their experience of the retreat. Attendees universally regarded the retreat as having value for them. Comparison of baseline to postretreat responses indicated that attendees felt that the retreat enhanced their abilities to be better physicians, resident supervisors, and leaders. Follow-up responses indicated significant increases in attendees' agreement that good leaders challenge the process, make decisions based on shared visions, allow others to act, recognize individual contributions, and serve as good role models. Results on the survival exercise indicated a high frequency with which team-based decisions surpassed individual members' decisions, highlighting the importance and value of teamwork to attendees. Our main findings were that: participants universally found this 1-day retreat beneficial in helping to develop teamwork and leadership skills and the experiential learning aspects of the retreat were more especially highly rated and highlighted the advantages of teamwork. In the context that this 1-day retreat was deemed useful by faculty and residents alike, further

Teambuilding and Leadership Training in an Internal Medicine Residency Training Program

Science.gov (United States)

Stoller, James K; Rose, Mark; Lee, Rita; Dolgan, Colleen; Hoogwerf, Byron J

2004-01-01

OBJECTIVE The purpose of this report is to describe and evaluate the impact of a 1-day retreat focused on developing leadership skills and teambuilding among postgraduate year 1 residents in an internal medicine residency. METHOD A group of organizers, including members of the staff, the chief medical residents, administrative individuals in the residency office, and an internal organizational development consultant convened to organize an off-site retreat with activities that would provide experiential learning regarding teamwork and leadership, including a “reef survival exercise” and table discussions regarding the characteristics of ideal leaders. In addition, several energizing activities and recreational free time was provided to enhance the interaction and teamwork dimensions of the retreat. To evaluate the impact of the retreat, attendees completed baseline and follow-up questionnaires regarding their experience of the retreat. RESULTS Attendees universally regarded the retreat as having value for them. Comparison of baseline to postretreat responses indicated that attendees felt that the retreat enhanced their abilities to be better physicians, resident supervisors, and leaders. Follow-up responses indicated significant increases in attendees’ agreement that good leaders challenge the process, make decisions based on shared visions, allow others to act, recognize individual contributions, and serve as good role models. Results on the survival exercise indicated a high frequency with which team-based decisions surpassed individual members’ decisions, highlighting the importance and value of teamwork to attendees. CONCLUSIONS Our main findings were that: participants universally found this 1-day retreat beneficial in helping to develop teamwork and leadership skills and the experiential learning aspects of the retreat were more especially highly rated and highlighted the advantages of teamwork. In the context that this 1-day retreat was deemed useful

Microscale soil structure development after glacial retreat - using machine-learning based segmentation of elemental distributions obtained by NanoSIMS

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Schweizer, Steffen; Schlueter, Steffen; Hoeschen, Carmen; Koegel-Knabner, Ingrid; Mueller, Carsten W.

2017-04-01

Soil organic matter (SOM) is distributed on mineral surfaces depending on physicochemical soil properties that vary at the submicron scale. Nanoscale secondary ion mass spectrometry (NanoSIMS) can be used to visualize the spatial distribution of up to seven elements simultaneously at a lateral resolution of approximately 100 nm from which patterns of SOM coatings can be derived. Existing computational methods are mostly confined to visualization and lack spatial quantification measures of coverage and connectivity of organic matter coatings. This study proposes a methodology for the spatial analysis of SOM coatings based on supervised pixel classification and automatic image analysis of the 12C, 12C14N (indicative for SOM) and 16O (indicative for mineral surfaces) secondary ion distributions. The image segmentation of the secondary ion distributions into mineral particle surface and organic coating was done with a machine learning algorithm, which accounts for multiple features like size, color, intensity, edge and texture in all three ion distributions simultaneously. Our workflow allowed the spatial analysis of differences in the SOM coverage during soil development in the Damma glacier forefield (Switzerland) based on NanoSIMS measurements (n=121; containing ca. 4000 particles). The Damma chronosequence comprises several stages of soil development with increasing ice-free period (from ca. 15 to >700 years). To investigate mineral-associated SOM in the developing soil we obtained clay fractions (2.2 g cm3). We found increased coverage and a simultaneous development from patchy-distributed organic coatings to more connected coatings with increasing time after glacial retreat. The normalized N:C ratio (12C14N: (12C14N + 12C)) on the organic matter coatings was higher in the medium-aged soils than in the young and mature ones in both heavy and light mineral fraction. This reflects the sequential accumulation of proteinaceous SOM in the medium-aged soils and C

Bilateral chronic subdural hematoma

DEFF Research Database (Denmark)

Andersen-Ranberg, Nina Christine; Rom Poulsen, Frantz; Bergholt, Bo

2017-01-01

OBJECTIVE Bilateral chronic subdural hematoma (bCSDH) is a common neurosurgical condition frequently associated with the need for retreatment. The reason for the high rate of retreatment has not been thoroughly investigated. Thus, the authors focused on determining which independent predictors...... are associated with the retreatment of bCSDH with a focus on surgical laterality. METHODS In a national database of CSDHs (Danish Chronic Subdural Hematoma Study) the authors retrospectively identified all bCSDHs treated in the 4 Danish neurosurgical departments over the 3-year period from 2010 to 2012...... that a separated hematoma density and the absence of postoperative drainage were independent predictors of retreatment. CONCLUSIONS In bCSDHs bilateral surgical intervention significantly lowers the risk of retreatment compared with unilateral intervention and should be considered when choosing a surgical...

Clinical responses to EGFR-tyrosine kinase inhibitor retreatment in non-small cell lung cancer patients who benefited from prior effective gefitinib therapy: a retrospective analysis

International Nuclear Information System (INIS)

Watanabe, Satoshi; Miyabayashi, Takao; Narita, Ichiei; Yoshizawa, Hirohisa; Tanaka, Junta; Ota, Takeshi; Kondo, Rie; Tanaka, Hiroshi; Kagamu, Hiroshi; Ichikawa, Kosuke; Koshio, Jun; Baba, Junko

2011-01-01

Gefitinib was the first epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) approved for the treatment of advanced non-small cell lung cancer (NSCLC). Few treatment options are available for NSCLC patients who have responded to gefitinib treatment and demonstrated tumor progression. The present study was conducted to evaluate the efficacy and toxicity of the 2 nd EGFR-TKI administration. We retrospectively analyzed 11 patients who had obtained a partial response (PR) or stable disease (SD) with gefitinib treatment and were re-treated with EGFR-TKI after failure of the initial gefitinib treatment. Three patients (27%) were treated with gefitinib as the 2 nd EGFR-TKI, and 8 patients (73%) received erlotinib. Only one patient (9%) showed PR, 7 (64%) achieved SD, and 3 (27%) had progressive disease. The disease control rate was 73% (95% CI, 43% - 91%) and the median progression-free survival was 3.4 months (95% CI, 2 - 5.2). The median overall survival from the beginning of the 2 nd EGFR-TKI and from diagnosis were 7.3 months (95% CI, 2.7 - 13) and 36.7 months (95% CI, 23.6 - 43.9), respectively. No statistical differences in PFS or OS were observed between gefitinib and erlotinib as the 2 nd EGFR-TKI (PFS, P = 0.23 and OS, P = 0.052). The toxicities associated with the 2 nd EGFR-TKI were generally acceptable and comparable to those observed for the initial gefitinib therapy. Our results indicate that a 2 nd EGFR-TKI treatment can be an effective treatment option for gefitinib responders

Simulating calving-front changes of Greenland’s marine-terminating glaciers

DEFF Research Database (Denmark)

Haubner, Konstanze

glacier retreat to a certain degree and foremost define the variation of retreat rates. The thesis implies the importance of incorporating glacier-front dynamics into ice sheet models in order to match observations and verifies atmospheric and oceanic forcing as important triggers for glacier retreat...... UI outlet glaciers. The change in mass flux resulting from the prescribed glacier retreat contributes to 70% of UI’s mass change over the simulation periods. The residual mass change is due to surface mass balance. A second simulation on the fastest UI glacier (UI-1) reveals that frontal melt rates...

Results of antiretroviral treatment interruption and intensification in advanced multi-drug resistant HIV infection from the OPTIMA trial.

Directory of Open Access Journals (Sweden)

Mark Holodniy

2011-03-01

Full Text Available Guidance is needed on best medical management for advanced HIV disease with multidrug resistance (MDR and limited retreatment options. We assessed two novel antiretroviral (ARV treatment approaches in this setting.We conducted a 2×2 factorial randomized open label controlled trial in patients with a CD4 count≤300 cells/µl who had ARV treatment (ART failure requiring retreatment, to two options (a re-treatment with either standard (≤4 ARVs or intensive (≥5 ARVs ART and b either treatment starting immediately or after a 12-week monitored ART interruption. Primary outcome was time to developing a first AIDS-defining event (ADE or death from any cause. Analysis was by intention to treat. From 2001 to 2006, 368 patients were randomized. At baseline, mean age was 48 years, 2% were women, median CD4 count was 106/µl, mean viral load was 4.74 log(10 copies/ml, and 59% had a prior AIDS diagnosis. Median follow-up was 4.0 years in 1249 person-years of observation. There were no statistically significant differences in the primary composite outcome of ADE or death between re-treatment options of standard versus intensive ART (hazard ratio 1.17; CI 0.86-1.59, or between immediate retreatment initiation versus interruption before re-treatment (hazard ratio 0.93; CI 0.68-1.30, or in the rate of non-HIV associated serious adverse events between re-treatment options.We did not observe clinical benefit or harm assessed by the primary outcome in this largest and longest trial exploring both ART interruption and intensification in advanced MDR HIV infection with poor retreatment options.Clinicaltrials.gov NCT00050089.

Results of an intervention for individuals and families with BRCA mutations: a model for providing medical updates and psychosocial support following genetic testing.

Science.gov (United States)

McKinnon, Wendy; Naud, Shelly; Ashikaga, Taka; Colletti, Rose; Wood, Marie

2007-08-01

: Providing medical management updates and long-term support to families with hereditary cancer syndromes in rural areas is a challenge. To address this, we designed a one-day retreat for BRCA1/2 carriers in our region. The retreat included educational updates about medical management, genetic privacy and discrimination, and addressed psychological and family issues. Evaluations completed at the conclusion of the retreat were overwhelmingly positive with requests for a similar event in the future. The impact of this retreat on a variety of health behaviors was assessed. Eligible participants completed questionnaires before and 6 months after the retreat. Questionnaires focused on lifestyle, cancer screening and prevention practices, psychological history and distress, decision-making regarding genetic testing, and family communication issues. For individuals who completed both the pre and post retreat questionnaires, one-half made lifestyle changes and nearly two-thirds increased cancer screening, initiated chemoprevention, completed or planned to complete preventative surgery in the future. We conclude that this type of forum provides a valuable opportunity for BRCA carriers and their families to receive updated medical information, share personal experiences, provide and receive support, as well as change health behaviors.

Rate of Mass Loss Across the Instability Threshold for Thwaites Glacier Determines Rate of Mass Loss for Entire Basin

Science.gov (United States)

Waibel, M. S.; Hulbe, C. L.; Jackson, C. S.; Martin, D. F.

2018-01-01

Rapid change now underway on Thwaites Glacier (TG) raises concern that a threshold for unstoppable grounding line retreat has been or is about to be crossed. We use a high-resolution ice sheet model to examine the mechanics of TG self-sustained retreat by nudging the grounding line just past the point of instability. We find that by modifying surface slope in the region of the grounding line, the rate of the forcing dictates the rate of retreat, even after the external forcing is removed. Grounding line retreats that begin faster proceed more rapidly because the shorter time interval for the grounding line to erode into the grounded ice sheet means relatively thicker ice and larger driving stress upstream of the boundary. Retreat is sensitive to short-duration re-advances associated with reduced external forcing where the bathymetry allows regrounding, even when an instability is invoked.

Reirradiation of healing murine skin

International Nuclear Information System (INIS)

Terry, N.H.A.; Aldana, M.W.; Travis, E.L.

1987-01-01

The most common way of assessing residual radiation damage in a tissue has been to retreat at a fixed time interval after a first treatment. Previous studies in skin have shown that the greatest proportion of remembered dose (20-40%) was seen if the retreatment interval was one month, shortly after the acute reaction caused by the first treatment has subsided. Moreover, the observed state of the foot at retreatment depended on the size of the first dose. After a priming dose of 22.5 Gy, the peak skin reaction of 0.8 returned to zero by Day 27. On retreatment at Day 30, the foot was indistinguishable from controls. After higher first doses, the feet still had significant reaction scores ranging from 0.5 to more than 1.0. Thus, in this present study, feet were retreated at a common level of healing rather than after a fixed time interval. Mice feet were irradiated with a range of X-ray doses (22.5-37.5 Gy) covering the threshold to full response. The feet were reirradiated when their skin reactions had fallen to a common value of 0.5. The time of this retreatment was therefore earlier (13 days) after the lowest priming dose (22.5 Gy) than after higher doses. In these latter instances retreatment times ranged from 18-40 days. These data are compared with those from schedules where the second irradiations were performed a fixed time after the first treatment

Incidence of apical crack formation and propagation during removal of root canal filling materials with different engine driven nickel-titanium instruments

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Taha Özyürek

2017-11-01

Full Text Available Objectives To determine the incidence of crack formation and propagation in apical root dentin after retreatment procedures performed using ProTaper Universal Retreatment (PTR, Mtwo-R, ProTaper Next (PTN, and Twisted File Adaptive (TFA systems. Materials and Methods The study consisted of 120 extracted mandibular premolars. One millimeter from the apex of each tooth was ground perpendicular to the long axis of the tooth, and the apical surface was polished. Twenty teeth served as the negative control group. One hundred teeth were prepared, obturated, and then divided into 5 retreatment groups. The retreatment procedures were performed using the following files: PTR, Mtwo-R, PTN, TFA, and hand files. After filling material removal, apical enlargement was done using apical size 0.50 mm ProTaper Universal (PTU, Mtwo, PTN, TFA, and hand files. Digital images of the apical root surfaces were recorded before preparation, after preparation, after obturation, after filling removal, and after apical enlargement using a stereomicroscope. The images were then inspected for the presence of new apical cracks and crack propagation. Data were analyzed with χ2 tests using SPSS 21.0 software. Results New cracks and crack propagation occurred in all the experimental groups during the retreatment process. Nickel-titanium rotary file systems caused significantly more apical crack formation and propagation than the hand files. The PTU system caused significantly more apical cracks than the other groups after the apical enlargement stage. Conclusions This study showed that retreatment procedures and apical enlargement after the use of retreatment files can cause crack formation and propagation in apical dentin.

Incidence of apical crack formation and propagation during removal of root canal filling materials with different engine driven nickel-titanium instruments.

Science.gov (United States)

Özyürek, Taha; Tek, Vildan; Yılmaz, Koray; Uslu, Gülşah

2017-11-01

To determine the incidence of crack formation and propagation in apical root dentin after retreatment procedures performed using ProTaper Universal Retreatment (PTR), Mtwo-R, ProTaper Next (PTN), and Twisted File Adaptive (TFA) systems. The study consisted of 120 extracted mandibular premolars. One millimeter from the apex of each tooth was ground perpendicular to the long axis of the tooth, and the apical surface was polished. Twenty teeth served as the negative control group. One hundred teeth were prepared, obturated, and then divided into 5 retreatment groups. The retreatment procedures were performed using the following files: PTR, Mtwo-R, PTN, TFA, and hand files. After filling material removal, apical enlargement was done using apical size 0.50 mm ProTaper Universal (PTU), Mtwo, PTN, TFA, and hand files. Digital images of the apical root surfaces were recorded before preparation, after preparation, after obturation, after filling removal, and after apical enlargement using a stereomicroscope. The images were then inspected for the presence of new apical cracks and crack propagation. Data were analyzed with χ 2 tests using SPSS 21.0 software. New cracks and crack propagation occurred in all the experimental groups during the retreatment process. Nickel-titanium rotary file systems caused significantly more apical crack formation and propagation than the hand files. The PTU system caused significantly more apical cracks than the other groups after the apical enlargement stage. This study showed that retreatment procedures and apical enlargement after the use of retreatment files can cause crack formation and propagation in apical dentin.

Do retreatment tuberculosis patients need special treatment response follow-up beyond the standard regimen? Finding of five-year retrospective study in pastoralist setting.

Science.gov (United States)

Getnet, Fentabil; Sileshi, Henok; Seifu, Wubareg; Yirga, Selam; Alemu, Abere Shiferaw

2017-12-12

execute DOTS should be strengthened and special follow-up mechanism should be in place to monitor treatment response of retreatment cases.

Micro-CT evaluation of the effectiveness of the combined use of rotary and hand instrumentation in removal of Resilon.

Science.gov (United States)

Asheibi, Fatma; Qualtrough, Alison J E; Mellor, Anthony; Withers, Philip J; Lowe, Tristan

2014-01-01

This study compares the effectiveness of ProTaper rotary files with ProTaper retreatment and K-files in the removal of Resilon or gutta percha (GP) from canals filled either by cold lateral condensation or thermal obturation using micro-CT. Ninety-six teeth were prepared using ProTaper files and allocated into four groups (n=24): Group-1 was filled with GP/AH-Plus and Group-2 with Resilon/RealSeal using cold lateral condensation. Group-3 was filled with GP/AH-Plus and Group-4 with Resilon/RealSeal using System B and Obtura II. The roots were scanned by micro-CT. Each group was divided into two subgroups (n=12): A, retreated using ProTaper files and B, using ProTaper retreatment and K-files. The roots were scanned to calculate the volume of the remaining material. With thermal obturation, roots filled with Resilon had significantly more remaining material than GP. Obturation using thermal technique resulted in significantly less remaining material than cold condensation except Resilon retreated using ProTaper retreatment and K-files.

Clinical analysis of the therapy for recurrent and intractable non-small cell lung cancer with combination of cryoablation and intervention

International Nuclear Information System (INIS)

Zhang Futong; Li Xiuli; Li Huijie; An Yonghui

2007-01-01

Objective: To explore the re-treatment approach for nonsmall-cell lung cancer (NSCLC )in clinic with therapeutic alliance of cryotherapy and interventional chemotherapy. Methods: Sixty two patients with uncontrolled NSCLC after common radiotherapy and (or)chemotherapy were re-treated with therapeutic alliance of cryotherapy and interventional chemotherapy, and their serum tumor markers of NSE, CEA, CY21- 1 and the value (I.S%,I.O.D%)of correlative protein in nucleolus region-Ag-NORs were tested before and after the re-treatment. Meanwhile, patients one year survival and therapeutic effect to NSCLC were recorded during the follow up. Results: After the re-treatment, distinguished decline of the serum tumor markers was observed (P<0.01)and values of Ag-NORs(I.S% and I.O.D%)were obviously lowered down. The therapeutic effect and one year survival were 79.03%(49/62)and 80.63%(50/62)respectively. Conclusion: Therapeutic alliance of cryotherapy and interventional chemotherapy is a kind of effective re-treatment for NSCLC and also as a new approach for the refractory NSCLC. (authors)

Increasing mass loss from Greenland's Mittivakkat Gletscher

DEFF Research Database (Denmark)

Hasholt, Bent; Mernild, S.H.; Knudsen, N.T.

2011-01-01

Warming in the Arctic during the past several decades has caused glaciers to thin and retreat, and recent mass loss from the Greenland Ice Sheet is well documented. Local glaciers peripheral to the ice sheet are also retreating, but few mass-balance observations are available to quantify that ret...... a local phenomenon, but are indicative of glacier changes in the broader region. Mass-balance observations for the MG therefore provide unique documentation of the general retreat of Southeast Greenland's local glaciers under ongoing climate warming....

Removal of Gutta-Percha/Zinc-Oxide-Eugenol Sealer or Gutta-Percha/Epoxy Resin Sealer from Severely Curved Canals: An In Vitro Study

Directory of Open Access Journals (Sweden)

Santhoshini Reddy

2011-01-01

Full Text Available The aim of this study was to compare the cleanliness of root canal walls after retreatment using two rotary retreatment files to hand instruments in severely curved canals obturated with gutta-percha and two different sealers. Single rooted mandibular premolars (n=90 with root curvatures were instrumented and obturated with gutta-percha and an epoxy resin (Group 1, n=45 or zinc oxide eugenol sealer (Group 2, n=45. Following retreatment of the specimens (n=15 ProTaper Universal Retreatment Files (Subgroup B or R-Endo retreatment files (Subgroup C after 1 month, split specimens were examined under a stereomicroscope and the percentage of remaining root filling material was statistically compared using one way ANOVA with Bonferroni adjustment for multiple comparisons (P=0.05. The R-Endo system performed significantly better than the other two file systems (P<0.05. None of the systems used in this study cleaned root canals thoroughly. The R-Endo system did provide cleaner walls when compared to the other instruments used. The type of root filling materials had an impact on the outcomes with all techniques.

Monitoring Glacier Changes of Recent 50 Years in the Upper Reaches of Heihe River Basin Based on Remotely-Sensed Data

International Nuclear Information System (INIS)

Qiang, Bie; Lei, He; Chuan-yan, Zhao

2014-01-01

The upper reach of the Heihe River Basin was selected as the study area. The distribution data of glaciers in the study area has been automatically derived from topographic maps made in 1960 and from Landsat TM images in 1990, 2000 and 2010 by object-oriented image interpretation method combined with expert knowledge rules. Spatial-temporal variations of glaciers were analyzed with GIS technology. Results show that glaciers have shrunk significantly by 138.90 km 2 during the period from 1960 to 2010. Compared with the data of 1960, 35.6% of glaciers have been retreating and the calculated average rate of glaciers retreating is 2.78 km 2 every year since 1960. The glacial retreating has been most significant if the glaciers have lower-elevation ablation areas and low-elevation accumulation areas. The temperature rising is the key factor of glacier retreating

Retreat from superficiality in architecture

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Aleksander Serafin

2016-03-01

Full Text Available The main aim is to present academic two-level method of design, called “theoretical modeling architecture” (TMA. It means the syllabus of design teaching that is strongly supported by the theory of architecture. The elaborated method results the higher number of students’ projects, that are related to the cultural heritage.

Ecological responses to experimental glacier-runoff reduction in alpine rivers

DEFF Research Database (Denmark)

Cauvy-Fraunié, Sophie; Andino, Patricio; Espinosa, Rodrigo

2016-01-01

Glacier retreat is a worldwide phenomenon with important consequences for the hydrological cycle and downstream ecosystem structure and functioning. To determine the effects of glacier retreat on aquatic communities, we conducted a 4-year flow manipulation in a tropical glacier-fed stream. Compared...

Tomography high Resolution CT findings of nontuberculous mycobacterial pulmonary disease: Comparison between the first treatment and the re treatment group

Energy Technology Data Exchange (ETDEWEB)

Gwak, Soon Hyuk; Cho, Bum Sang; Jeon, Min Hee; Kim, Eun Young; Kang, Min Ho; Yi, Kyung Sik; Lee, Seung Young; Kim, Sung Jin; Lee, Ki Man [Chungbuk National Univ., Cheongju, (Korea, Republic of)

2012-06-15

To analyze and compare the thin section CT findings of first and re treatment nontuberculous mycobacterial (NTM) pulmonary disease. Between January 2005 and April 2010, 121 patients with positive sputum culture for NTM were recruited. We included only 32 patients underwent high resolution chest CT and were confirmed by American Thoracic Society criteria NTM pulmonary infection (first treatment 15, re treatment 17 patients). CT images of 32 patients were reviewed retrospectively. We evaluated the frequency and laterality of the followings; nodule, increased density, bronchial change, parenchymal change. The significantly frequent CT findings of the re treatment NTM group were well defined nodules (retreatment 82.4%, first treatment 33.3%, p = 0.00), consolidations (retreatment 88.2%, first treatment 53.3%, p = 0.03), bronchial changes (bronchiectasis; retreatment 100%, first treatment 66.6%, p = 0.01, bronchial narrowing; retreatment 23.5%, first treatment 0%, p = 0.04 and mucoid impaction; retreatment-58.8%, first treatment-20.0%, p = 0.03) and atelectasis with bronchiectasis (retreatment-88.2%, first treatment 26.7%, p = 0.00). However, most of the evaluated thin section CT findings, such as centrilobular and ill defined nodules, lobular, segmental and subpleural consolidations, ground glass attenuation, bronchial wall thickening, cavities, pleural lesions, fibrotic band, emphysema and laterality of lesions, have not shown significant differences between first treatment and the re treatment group. Thin section CT findings of well defined nodules, consolidations, bronchial changes (bronchiectasis, bronchial narrowing and mucoid impaction) and atelectasis with bronchiectasis are highly suggestive of re treatment NTM pulmonary disease.

Philosophy and Revolution: Badiou's Infidelity to the Event

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George Vassilacopoulos

2006-10-01

Full Text Available Our aim in this paper is to give reasons for thinking that Badioursquo;s philosophy is not prepared to follow through all the consequences of the historical retreat of the political event. We want to suggest that it is important to come to terms with the implications of this retreat as no less a revolutionary aspect of the revolution. Whereas fidelity to the event demands that we not be selective in following the consequences of an event, fidelity to the eventrsquo;s retreat points to a more direct relation of philosophy to the event than Badiou allows. In the first section of our paper we outline the philosophical orientation that informs our encounter with Badioursquo;s thought. In the second we examine the relationship between philosophy and the political event in order to set the context for the elaboration of our claim in the third section that fidelity to the event calls for attention not only to the demands of its emergence but also to those associated with the eventrsquo;s retreat. In the final section we indicate how the retreat of the political event might give rise to the philosophical subject and to the requirements of a philosophy of the event.

Significance of definitions of relapse after discontinuation of oral antivirals in HBeAg-negative chronic hepatitis B.

Science.gov (United States)

Papatheodoridis, George V; Manolakopoulos, Spilios; Su, Tung-Hung; Siakavellas, Spyros; Liu, Chun-Jen; Kourikou, Anastasia; Yang, Hung-Chih; Kao, Jia-Horng

2017-08-31

Relapses are observed in most hepatitis B e antigen (HBeAg)-negative chronic hepatitis B patients who discontinue treatment with nucleos(t)ide analogues (NAs); however, the rates of relapse vary widely among studies, and whether all patients with relapse need retreatment is unclear. The aim of this study was to assess the impact of different definitions on the rates of posttreatment relapse and therefore on the probability of retreatment in patients who have discontinued effective long-term NA therapy. In total, 130 HBeAg-negative chronic hepatitis B patients without cirrhosis and before NA treatment were included. All had on-therapy virological remission for ≥24 months and close follow-up for ≥12 months after stopping NA treatment or until retreatment, which started on stringent predefined criteria. Relapses rates based on several predetermined definitions of virological and perhaps biochemical criteria were assessed. The median duration of therapy was 60 months and the median duration of on-therapy virological remission was 43 months. During a median off-NAs follow-up of 15 months, no patient experienced liver decompensation or died. Cumulative relapse rates were 2%-49%, 4%-73%, 11%-82%, and 16%-90% at 3, 6, 12, and 24 months, respectively, whereas cumulative retreatment rates were 15%, 22%, and 40% at 6, 12, and 24 months, respectively, after discontinuation of NA therapy. No patient characteristic was independently associated with the probability of relapse based on at least two definitions or of retreatment. In HBeAg-negative chronic hepatitis B patients who discontinue NA therapy, the definition of relapse has a great impact on off-NAs relapse rates and potentially on the probability of retreatment. Regardless of definition, off-NAs relapses cannot be easily predicted by patient characteristics. A substantial proportion of such patients may not require retreatment if stringent criteria are adopted. (Hepatology 2017). © 2017 by the American Association

The significant impact of framing coils on long-term outcomes in endovascular coiling for intracranial aneurysms: how to select an appropriate framing coil.

Science.gov (United States)

Ishida, Wataru; Sato, Masayuki; Amano, Tatsuo; Matsumaru, Yuji

2016-09-01

OBJECTIVE The importance of a framing coil (FC)-the first coil inserted into an aneurysm during endovascular coiling, also called a lead coil or a first coil-is recognized, but its impact on long-term outcomes, including recanalization and retreatment, is not well established. The purposes of this study were to test the hypothesis that the FC is a significant factor for aneurysmal recurrence and to provide some insights on appropriate FC selection. METHODS The authors retrospectively reviewed endovascular coiling for 280 unruptured intracranial aneurysms and gathered data on age, sex, aneurysm location, aneurysm morphology, maximal size, neck width, adjunctive techniques, recanalization, retreatment, follow-up periods, total volume packing density (VPD), volume packing density of the FC, and framing coil percentage (FCP; the percentage of FC volume in total coil volume) to clarify the associated factors for aneurysmal recurrence. RESULTS Of 236 aneurysms included in this study, 33 (14.0%) had recanalization, and 18 (7.6%) needed retreatment during a mean follow-up period of 37.7 ± 16.1 months. In multivariate analysis, aneurysm size (odds ratio [OR] = 1.29, p < 0.001), FCP < 32% (OR 3.54, p = 0.009), and VPD < 25% (OR 2.96, p = 0.015) were significantly associated with recanalization, while aneurysm size (OR 1.25, p < 0.001) and FCP < 32% (OR 6.91, p = 0.017) were significant predictors of retreatment. VPD as a continuous value or VPD with any cutoff value could not predict retreatment with statistical significance in multivariate analysis. CONCLUSIONS FCP, which is equal to the FC volume as a percentage of the total coil volume and is unaffected by the morphology of the aneurysm or the measurement error in aneurysm length, width, or height, is a novel predictor of recanalization and retreatment and is more significantly predictive of retreatment than VPD. To select FCs large enough to meet the condition of FCP ≥ 32% is a potential relevant factor for better

Dynamic response of Sjögren Inlet glaciers, Antarctic Peninsula, to ice shelf breakup derived from multi-mission remote sensing time series.

NARCIS (Netherlands)

Seehaus, T.C.; Marinsek, S.; Skvarca, P.; van Wessem, J.M.; Reijmer, C.H.; Seco, J.L.; Braun, M.

2016-01-01

The substantial retreat or disintegration of numerous ice shelves has been observed on the Antarctic Peninsula. The ice shelf in the Prince Gustav Channel has retreated gradually since the late 1980s and broke up in 1995. Tributary glaciers reacted with speed-up, surface lowering and increased ice

Evaluation of apically extruded debris during removal of gutta-percha and ResilonTM using different instrumentation techniques

Directory of Open Access Journals (Sweden)

Pešić Dragana

2018-01-01

Full Text Available Background/Aim. Apical extrusion of material is considered as one of the very important factor for endodontic treatment success. Microorganisms, necrotic tissue, filling material and irrigants, which can be extruded apically during endodontic retreatment, may jeopardize the success of the therapy. The aim of this in vitro study was to quantitatively evaluate the amount of apically extruded debris during endodontic retreatment of teeth obturated with two different materials, using one hand and three rotary instrumentation techniques. Methods. Ninety-six extracted single-rooted teeth were endodontically treated and enlarged to size 40 using BioRaCe system, and then randomly divided into 8 groups of 12 specimens each. Half of the specimens were obturated with gutta-percha and AH Plus® sealer and another half with RealSeal SE system, using lateral condensation technique. Retreatment was performed using: Hedström files; ProFile rotary files; ProTaper Retreatment system and D-RaCe system. Apically extruded debris was collected in pre-weighed Eppendorf tubes and evaluated using an electronic microbalance. Data were analyzed statistically using t-test and analysis of variance. Results. In the AH Plus/gutta-percha group, all tested rotary instruments gave significantly less extruded debris compared with Hedström files (p < 0.05. In theRealSeal group, there was significant difference between DRaCe and Hedström instruments (p < 0.05. Conclusion. All retreatment techniques resulted in apical extrusion. DRaCe system produced significantly less extruded debris compared to hand files. No significant difference was found when comparing two instruments specially designed for retreatment: D-RaCe and ProTaper systems.

College Football and Public Crisis: Appropriate Actions and Justifications after the Kennedy Assassination.

Science.gov (United States)

Brown, Robert S.

This paper contends that domestic response to John F. Kennedy's assassination took two basic forms in the United States: active crisis management and retreat. According to the paper, while government, churches, and the media engaged in active crisis management, businesses and schools closed, and the public retreated to mourn rather than to…

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Abstract. The widespread retreat of glaciers can be considered as a response to the climate change. Being the largest retreating glacier–ice shelf system in East Antarctica, the Amery Ice Shelf–Lambert Glacier system plays an important role in contributing to sea level rise as well as the surrounding environment and climate.

Effect of Instrument Design and Access Outlines on the Removal of Root Canal Obturation Materials in Oval-shaped Canals.

Science.gov (United States)

Niemi, Tuomas K; Marchesan, Melissa A; Lloyd, Adam; Seltzer, Robert J

2016-10-01

The aim of this study was to compare the effectiveness of TRUShape (TS) instruments with ProFile Vortex Blue (VB) instruments for the removal of obturation materials during retreatment of single-canal mandibular premolars performed through 2 access outlines. Initial root canal treatment was completed through a contracted endodontic cavity (CEC) design. Canals were instrumented to an F2 ProTaper instrument, obturated with warm lateral condensation of gutta-percha with AH Plus sealer, and allowed to set for 30 days at 37°C and 100% humidity. For retreatment, specimens were divided into 2 groups (n = 24) on the basis of access outline, CEC or traditional endodontic cavity (TEC). Retreatment was initiated by using ProTaper Retreatment instruments (D1-D3). Specimens were then stratified, further divided (n = 12), and reinstrumented up to TS 40 .06v or 40 .06 VB. Irrigation was performed by using 8.25% NaOCl and QMix 2in1. Retreatment time was recorded. Teeth were sectioned and photographed, and the percentage of remaining obturation materials was measured. Data were analyzed with Kruskal-Wallis analysis of variance for two-factor tests (α canal surface when compared with TEC-VB, CEC-TS, and TEC-TS (P ≤ .05). None of these other combinations were different from each other (P > .05). Significantly more time was required for retreatment with CEC-TS (27.68 ± 1.4 minutes) than the other groups (P root canal surface of mandibular premolars. However, in the presence of a CEC access design, using TS instruments removed more obturating material in single-rooted, oval-shaped canals. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Hepatitis C Virus Resistance Testing in Genotype 1: The Changing Role in Clinical Utility.

Science.gov (United States)

Molino, Suzanne; Martin, Michelle T

2017-09-01

To review the role and utility of baseline resistance testing with currently available and pipeline genotype 1 hepatitis C virus (HCV) treatment. Authors reviewed liver meeting abstracts for data on currently-available and pipeline genotype 1 retreatment regimens from January 1, 2015, to March 23, 2017. Additional trials were identified from a review of clinicaltrials.gov using the pipeline medication names. Authors identified reports of current and pipeline genotype 1 retreatment regimens. Seven references were clinical study results presented at the meetings of the American Association for the Study of Liver Diseases and the European Association for the Study of the Liver, and 2 studies were from clinicaltrials.gov . Retreatment trial data of currently available salvage regimens indicate that baseline NS5A resistance-associated substitutions (RASs) may decrease sustained virological response (SVR) rates when retreating with ledipasvir/sofosbuvir but are not affected when using elbasvir/grazoprevir + sofosbuvir + ribavirin, paritaprevir/ritonavir/ombitasvir + dasabuvir + sofosbuvir, or sofosbuvir/velpatasvir + ribavirin. Pipeline data indicate that baseline NS5A RASs do not affect SVR rates when retreating with sofosbuvir/velpatasvir/voxilaprevir or glecaprevir/pibrentasvir. Baseline resistance testing was used for decisional support for 3 clinical scenarios in patients with HCV genotype 1 infection at the time of manuscript submission. Pending the approval of 2 new direct-acting antiviral regimens in the third quarter of 2017, the rapidly evolving HCV treatment guidelines will likely reflect a decreased clinical utility for resistance testing.

Advance and Retreat of Baili Necktie

Institute of Scientific and Technical Information of China (English)

无

2008-01-01

@@ "This trip to Europe is fruitful." Mr.Liu Dejun,general manager of Zhejiang Baili Necktie & Accessory Co.,Ltd,said as he come back from the Europe and couldn't help holding his excitement."We negotiated with professional design organizations about mutual cooperation and contacted some wholesalers with the hope of merger and acquisition." The 10-day exploratory trip greatly boosted his confidence.

The CEA and nuclear energy applications

International Nuclear Information System (INIS)

1980-01-01

With PWR reactors, CEA has applied a large part of its activities on steam generators, whilst other technical studies have involved components, maintenance, thermo-hydraulics, safety, materials, instrumentation apparatus and controls. For small light-water reactors, studies carried out have led to development of the Thermos Project: demonstrating the validity of urban heating derived from a pool-type reactor. Other studies have involved fast reactors (manufacture of fissile fuel assemblies, contributions toward the development of the Superphenix project and longer-term studies involving the overall breeder line). Finally, studies on the retreatment of irradiated fuels: aside from the retreatment of irradiated fuel programmes, CEA is pursuing its work on the TOR Project (large-scale pilot for retreatment of fast-neutron fuels) [fr

Similarly Torn, Differentially Shorn? The Experience and Management of Conflict between Multiple Roles, Relationships, and Social Categories

Directory of Open Access Journals (Sweden)

Janelle M. Jones

2017-10-01

Full Text Available In three studies we examined the experience and management of conflict between different types of multiple identities. Participants described a conflict between pairs of role, relational, or social identities before rating the experience (i.e., magnitude, stress, and growth and management of conflict on a newly developed scale assessing four strategies: reconciliation, where identities are integrated, realignment, where one identity is chosen over another, retreat, where both identities are avoided, and reflection, where fit (with others, situation determines identity selection. In general, the types of identities mattered for conflict management but not its experience: Magnitude and growth did not differ, however, stress was greater for role identity conflicts (Study 3 only and participants endorsed the use of more realignment for role conflicts (Study 2 and more retreat for relational conflicts (Study 3 relative to other types of identity conflicts. Furthermore, findings suggested that the perceived flexibility of identities, not their importance or valence, were associated with realignment and retreat for roles and with retreat for relationships. Experiencing conflicts between multiple identities leaves people similarly torn, but multiple roles and relationships may be differentially shorn to manage conflict.

Similarly Torn, Differentially Shorn? The Experience and Management of Conflict between Multiple Roles, Relationships, and Social Categories

Science.gov (United States)

Jones, Janelle M.; Hynie, Michaela

2017-01-01

In three studies we examined the experience and management of conflict between different types of multiple identities. Participants described a conflict between pairs of role, relational, or social identities before rating the experience (i.e., magnitude, stress, and growth) and management of conflict on a newly developed scale assessing four strategies: reconciliation, where identities are integrated, realignment, where one identity is chosen over another, retreat, where both identities are avoided, and reflection, where fit (with others, situation) determines identity selection. In general, the types of identities mattered for conflict management but not its experience: Magnitude and growth did not differ, however, stress was greater for role identity conflicts (Study 3 only) and participants endorsed the use of more realignment for role conflicts (Study 2) and more retreat for relational conflicts (Study 3) relative to other types of identity conflicts. Furthermore, findings suggested that the perceived flexibility of identities, not their importance or valence, were associated with realignment and retreat for roles and with retreat for relationships. Experiencing conflicts between multiple identities leaves people similarly torn, but multiple roles and relationships may be differentially shorn to manage conflict. PMID:29051744

Similarly Torn, Differentially Shorn? The Experience and Management of Conflict between Multiple Roles, Relationships, and Social Categories.

Science.gov (United States)

Jones, Janelle M; Hynie, Michaela

2017-01-01

In three studies we examined the experience and management of conflict between different types of multiple identities. Participants described a conflict between pairs of role, relational, or social identities before rating the experience (i.e., magnitude, stress, and growth) and management of conflict on a newly developed scale assessing four strategies: reconciliation , where identities are integrated, realignment , where one identity is chosen over another, retreat , where both identities are avoided, and reflection , where fit (with others, situation) determines identity selection. In general, the types of identities mattered for conflict management but not its experience: Magnitude and growth did not differ, however, stress was greater for role identity conflicts ( Study 3 only ) and participants endorsed the use of more realignment for role conflicts ( Study 2 ) and more retreat for relational conflicts ( Study 3 ) relative to other types of identity conflicts. Furthermore, findings suggested that the perceived flexibility of identities, not their importance or valence, were associated with realignment and retreat for roles and with retreat for relationships. Experiencing conflicts between multiple identities leaves people similarly torn, but multiple roles and relationships may be differentially shorn to manage conflict.

Predicting coastal cliff erosion using a Bayesian probabilistic model

Science.gov (United States)

Hapke, Cheryl J.; Plant, Nathaniel G.

2010-01-01

Regional coastal cliff retreat is difficult to model due to the episodic nature of failures and the along-shore variability of retreat events. There is a growing demand, however, for predictive models that can be used to forecast areas vulnerable to coastal erosion hazards. Increasingly, probabilistic models are being employed that require data sets of high temporal density to define the joint probability density function that relates forcing variables (e.g. wave conditions) and initial conditions (e.g. cliff geometry) to erosion events. In this study we use a multi-parameter Bayesian network to investigate correlations between key variables that control and influence variations in cliff retreat processes. The network uses Bayesian statistical methods to estimate event probabilities using existing observations. Within this framework, we forecast the spatial distribution of cliff retreat along two stretches of cliffed coast in Southern California. The input parameters are the height and slope of the cliff, a descriptor of material strength based on the dominant cliff-forming lithology, and the long-term cliff erosion rate that represents prior behavior. The model is forced using predicted wave impact hours. Results demonstrate that the Bayesian approach is well-suited to the forward modeling of coastal cliff retreat, with the correct outcomes forecast in 70–90% of the modeled transects. The model also performs well in identifying specific locations of high cliff erosion, thus providing a foundation for hazard mapping. This approach can be employed to predict cliff erosion at time-scales ranging from storm events to the impacts of sea-level rise at the century-scale.

Rapid Holocene thinning of outlet glaciers followed by readvance in the western Ross Embayment, Antarctica

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Jones, R. S.; Whitmore, R.; Mackintosh, A.; Norton, K. P.; Eaves, S.; Stutz, J.

2017-12-01

Investigating Antarctic deglaciation following the LGM provides an opportunity to better understand patterns, mechanisms and drivers of ice sheet retreat. In the Ross Sea sector, geomorphic features preserved on the seafloor indicate that streaming East Antarctic outlet glaciers once extended >100 km offshore of South Victoria Land prior to back-stepping towards their modern configurations. In order to adequately interpret the style and causes of this retreat, the timing and magnitude of corresponding ice thickness change is required. We present new constraints on ice surface lowering from Mawson Glacier, an outlet of the East Antarctic Ice Sheet that flows into the western Ross Sea. Surface-exposure (10Be) ages from samples collected in elevation transects above the modern ice surface reveal that rapid thinning occurred at 5-8 ka, broadly coeval with new ages of grounding-line retreat at 6 ka and rapid thinning recorded at nearby Mackay Glacier at 7 ka. Our data also show that a moraine formed near to the modern ice margin of Mawson Glacier at 0.8 ka, which, together with historical observations, indicates that glaciers in this region readvanced during the last thousand years. We argue that 1) the accelerated thinning of outlet glaciers was driven by local grounding-line retreat through overdeepened basins during the early-mid Holocene, and 2) the glaciers subsequently readvanced, possibly linked to late Holocene sea-ice expansion, before retreating to their current positions. Our work demonstrates that these outlet glaciers were closely coupled to environmental and topography-induced perturbations near their termini throughout the Holocene.

Mass Balance Evolution of Black Rapids Glacier, Alaska, 1980–2100, and Its Implications for Surge Recurrence

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Christian Kienholz

2017-07-01

Full Text Available Surge-type Black Rapids Glacier, Alaska, has undergone strong retreat since it last surged in 1936–1937. To assess its evolution during the late Twentieth and Twenty-first centuries and determine potential implications for surge likelihood, we run a simplified glacier model over the periods 1980–2015 (hindcasting and 2015–2100 (forecasting. The model is forced by daily temperature and precipitation fields, with downscaled reanalysis data used for the hindcasting. A constant climate scenario and an RCP 8.5 scenario based on the GFDL-CM3 climate model are employed for the forecasting. Debris evolution is accounted for by a debris layer time series derived from satellite imagery (hindcasting and a parametrized debris evolution model (forecasting. A retreat model accounts for the evolution of the glacier geometry. Model calibration, validation and parametrization rely on an extensive set of in situ and remotely sensed observations. To explore uncertainties in our projections, we run the glacier model in a Monte Carlo fashion, varying key model parameters and input data within plausible ranges. Our results for the hindcasting period indicate a negative mass balance trend, caused by atmospheric warming in the summer, precipitation decrease in the winter and surface elevation lowering (climate-elevation feedback, which exceed the moderating effects from increasing debris cover and glacier retreat. Without the 2002 rockslide deposits on Black Rapids' lower reaches, the mass balances would be more negative, by ~20% between the 2003 and 2015 mass-balance years. Despite its retreat, Black Rapids Glacier is substantially out of balance with the current climate. By 2100, ~8% of Black Rapids' 1980 area are projected to vanish under the constant climate scenario and ~73% under the RCP 8.5 scenario. For both scenarios, the remaining glacier portions are out of balance, suggesting continued retreat after 2100. Due to mass starvation, a surge in the Twenty

Sea-ice indicators of polar bear habitat

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Stern, Harry L.; Laidre, Kristin L.

2016-09-01

Nineteen subpopulations of polar bears (Ursus maritimus) are found throughout the circumpolar Arctic, and in all regions they depend on sea ice as a platform for traveling, hunting, and breeding. Therefore polar bear phenology - the cycle of biological events - is linked to the timing of sea-ice retreat in spring and advance in fall. We analyzed the dates of sea-ice retreat and advance in all 19 polar bear subpopulation regions from 1979 to 2014, using daily sea-ice concentration data from satellite passive microwave instruments. We define the dates of sea-ice retreat and advance in a region as the dates when the area of sea ice drops below a certain threshold (retreat) on its way to the summer minimum or rises above the threshold (advance) on its way to the winter maximum. The threshold is chosen to be halfway between the historical (1979-2014) mean September and mean March sea-ice areas. In all 19 regions there is a trend toward earlier sea-ice retreat and later sea-ice advance. Trends generally range from -3 to -9 days decade-1 in spring and from +3 to +9 days decade-1 in fall, with larger trends in the Barents Sea and central Arctic Basin. The trends are not sensitive to the threshold. We also calculated the number of days per year that the sea-ice area exceeded the threshold (termed ice-covered days) and the average sea-ice concentration from 1 June through 31 October. The number of ice-covered days is declining in all regions at the rate of -7 to -19 days decade-1, with larger trends in the Barents Sea and central Arctic Basin. The June-October sea-ice concentration is declining in all regions at rates ranging from -1 to -9 percent decade-1. These sea-ice metrics (or indicators of habitat change) were designed to be useful for management agencies and for comparative purposes among subpopulations. We recommend that the National Climate Assessment include the timing of sea-ice retreat and advance in future reports.

Current glaciation of the Chikhachev ridge (South-Eastern Altai and its dynamics after maximum of the Little Ice Age

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D. A. Ganyushkin

2016-01-01

Full Text Available Glaciation of the Chikhachev ridge (South-Eastern Altai remains poorly known: field observations were not performed since the mid-twentieth century, available schemes and estimates of the glaciation and its scale made on the basis of remote sensing cover only a part of the glaciers, reconstructions of the Little Ice Age (LIA glaciations are absent. This research was based on interpretation of the satellite images: Landsat-4 (1989, Landsat-7 (2001, and Spot-5 (2011, as well as with the use of data of the field season of 2015. Characteristics of glaciations of the Chikhachev ridge as the whole and of its individual centers (Talduair massif, Mongun-Taiga-Minor massif, and southern part of the Chikhachev ridge were determined for the first time. Recent glaciation is represented by 7 glaciers with their total area of 1.12 km2 in the Talduair massif, by 5 glaciers with total area of 0.75 km2 in the Mongun-Taiga-Minor massif, and by 85 glaciers with total area of 29 km2 in the southern part of the Chikhachev ridge. Since the LIA maximum, areas of glaciers decreased by 61% in the Talduair massif, by 74% in the Mongun-Taiga-Minor massif, by 56% in the southern part of the Chikhachev ridge with simultaneous lifting of the firn line by 50 m, 65 m, and 70 m, respectively.The largest rates of the glacier contractions were determined for the period 1989–2011. Different mechanisms of the glacier retreats were shown by the example of the glacier complexes Burgastyn-Gol (one-sided retreat and disintegration and the Grigorjev glacier (gradual retreat of the tongue. Retreat of the Grigorjev glacier has been reconstructed for the period from the LIA maximum until 2015. Average rate of the retreat increased from 1,6 m/year in 1957–1989 up to 11,3 m/year in 2011–2015. The present-day scales of the glaciers and rates of their retreating do not significantly differ from estimations made by other researchers for the nearest centers of glaciation of the

Sea-ice induced growth decline in Arctic shrubs.

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Forchhammer, Mads

2017-08-01

Measures of increased tundra plant productivity have been associated with the accelerating retreat of the Arctic sea-ice. Emerging studies document opposite effects, advocating for a more complex relationship between the shrinking sea-ice and terrestrial plant productivity. I introduce an autoregressive plant growth model integrating effects of biological and climatic conditions for analysing individual ring-width growth time series. Using 128 specimens of Salix arctica , S. glauca and Betula nana sampled across Greenland to Svalbard, an overall negative effect of the retreating June sea-ice extent was found on the annual growth. The negative effect of the retreating June sea-ice was observed for younger individuals with large annual growth allocations and with little or no trade-off between previous and current year's growth. © 2017 The Author(s).

A GIS tool for two-dimensional glacier-terminus change tracking

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Urbanski, Jacek Andrzej

2018-02-01

This paper presents a Glacier Termini Tracking (GTT) toolbox for the two-dimensional analysis of glacier-terminus position changes. The input consists of a vector layer with several termini lines relating to the same glacier at different times. The output layers allow analyses to be conducted of glacier-terminus retreats, changes in retreats over time and along the ice face, and glacier-terminus fluctuations over time. The application of three tools from the toolbox is demonstrated via the analysis of eight glacier-terminus retreats and fluctuations at the Hornsund fjord in south Svalbard. It is proposed that this toolbox may also be useful in the study of other line features that change over time, like coastlines and rivers. The toolbox has been coded in Python and runs via ArcGIS.

FibroTest is an independent predictor of virologic response in chronic hepatitis C patients retreated with pegylated interferon alfa-2b and ribavirin in the EPIC³ program.

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Poynard, Thierry; Munteanu, Mona; Colombo, Massimo; Bruix, Jordi; Schiff, Eugene; Terg, Ruben; Flamm, Steven; Moreno-Otero, Ricardo; Carrilho, Flair; Schmidt, Warren; Berg, Thomas; McGarrity, Thomas; Heathcote, E Jenny; Gonçales, Fernando; Diago, Moises; Craxi, Antonio; Silva, Marcelo; Boparai, Navdeep; Griffel, Louis; Burroughs, Margaret; Brass, Clifford; Albrecht, Janice

2011-02-01

EPIC-3 is a prospective, international study that has demonstrated the efficacy of PEG-IFN alfa-2b plus weight-based ribavirin in patients with chronic hepatitis C and significant fibrosis who previously failed any interferon-alfa/ribavirin therapy. The aim of the present study was to assess FibroTest (FT), a validated non-invasive marker of fibrosis in treatment-naive patients, as a possible alternative to biopsy as the baseline predictor of subsequent early virologic (EVR) and sustained virologic response (SVR) in previously treated patients. Of 2312 patients enrolled, 1459 had an available baseline FT, biopsy, and complete data. Uni- (UV) and multi-variable (MV) analyses were performed using FT and biopsy. Baseline characteristics were similar as in the overall population; METAVIR stage: 28% F2, 29% F3, and 43% F4, previous relapsers 29%, previous PEG-IFN regimen 41%, high baseline viral load (BVL) 64%. 506 patients (35%) had undetectable HCV-RNA at TW12 (TW12neg), with 58% achieving SVR. The accuracy of FT was similar to that in naive patients: AUROC curve for the diagnosis of F4 vs F2=0.80 (p<0.00001). Five baseline factors were associated (p<0.001) with SVR in UV and MV analyses (odds ratio: UV/MV): fibrosis stage estimated using FT (4.5/5.9) or biopsy (1.5/1.6), genotype 2/3 (4.5/5.1), BVL (1.5/1.3), prior relapse (1.6/1.6), previous treatment with non-PEG-IFN (2.6/2.0). These same factors were associated (p ≤ 0.001) with EVR. Among patients TW12neg, two independent factors remained highly predictive of SVR by MV analysis (p ≤ 0.001): genotype 2/3 (odds ratio=2.9), fibrosis estimated with FT (4.3) or by biopsy (1.5). FibroTest at baseline is a possible non-invasive alternative to biopsy for the prediction of EVR at 12 weeks and SVR, in patients with previous failures and advanced fibrosis, retreated with PEG-IFN alfa-2b and ribavirin. Copyright © 2010 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

The use of rites of passage in strengthening the psychosocial wellbeing of orphaned children in Botswana.

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Thamuku, Masego; Daniel, Marguerite

2012-10-01

Children who have been bereaved in the context of AIDS may experience many challenges to their psychosocial wellbeing. Programmes to help orphaned children are usually anchored in child rights. As the individual focus of rights-based approaches is inept in African collectivist culture, NGOs tend to make use of group approaches in psychosocial support programmes. One orphan-strengthening programme in Botswana, called the Ark for Children, uses rites of passage and rites of affirmation as part of a therapeutic retreat. This study explored how rites of passage and rites of affirmation contribute to psychosocial strengthening of orphaned children in Botswana. Ten orphaned children were involved in five rounds of data collection during a 16-day therapeutic retreat; and eight social workers answered questions on the effectiveness of the therapy. A supplementary document analysis was also completed, which included retreat reports since 2001 and correspondence from community-based support workers and graduates of the programme. Participants reported that the rites used during the retreat helped them to commit to therapeutic transformation. During a retreat, all the participants witness and support each individual going through each rite - a process reported to foster and strengthen group formation. It was documented that the symbols used as part of the themed rites of affirmation are used by participants for years afterwards as reminders of their transformation and commitment to the group. We conclude that rites of passage can provide a powerful tool to help children commit to therapeutic transformation, build the supportive group, and enable the community to recognise and affirm that the children return as changed individuals and members of the group.

Trench Advance By the Subduction of Buoyant Features - Application to the Izu-Bonin-Marianas Arc

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Goes, S. D. B.; Fourel, L.; Morra, G.

2014-12-01

Most subduction trenches retreat, not only today but throughout the Cenozoic. However, a few trenches clearly advance during part of the evolution, including Izu-Bonin Marianas (IBM) and Kermadec. Trench retreat is well understood as a basic consequence of slab pull, but it is debated what causes trench advance. The IBM trench underwent a complex evolution: right after its initiation, it rotated clockwise, leading to very fast retreat in the north and slow retreat in the south. But since 10-15 Ma, IBM trench motions have switched to advance at the southern end, and since 5 Ma also the northern end is advancing. Based on 2-D subduction models, it has been proposed proposed that the change in age of the subducting plate at the IBM trench (from 40-70 m.y. at the initiation of the trench 45 m.y. ago to 100-140 m.y. lithosphere subducting at the trench today) and its effect on plate strength could explain the transition from trench retreat to trench advance, and that the age gradient (younger in the north and older in the south) could explain the rotation of the trench. However, with new 3-D coupled fluid-solid subduction model where we can include such lateral age gradients, we find that this does not yield the observed behaviour. Instead, we propose an alternative mechanism, involving the subduction of the buoyant Caroline Island Ridge at the southern edge of the Mariana trench and show that it can explain both trench motion history and the current morphology of the IBM slab as imaged by seismic tomography.

The Influence of Body Mass Index on Outcomes in Ureteroscopy: Results from the Clinical Research Office of Endourological Society URS Global Study.

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Krambeck, Amy; Wijnstok, Nienke; Olbert, Peter; Mitroi, George; Bariol, Simon; Shah, Hemendra N; El-Abd, Ahmed S; Onal, Bulent; de la Rosette, Jean

2017-01-01

Although ureteroscopy (URS) has been established as a viable treatment for stones in obese patients, its safety and success has not been fully elucidated. The current study describes the worldwide prevalence of obesity in patients with urolithiasis and examines trends in URS outcomes, safety, and efficacy. This study utilized the Clinical Research Office of the Endourological Society (CROES) URS Global Study, which was a prospective, multicenter study including 11,885 patients treated with URS for urinary stones at 1 of 114 urology departments across 32 countries. The relationship between body mass index (BMI), diabetes, and creatinine, with retreatment, stone-free rates, complications, and long hospital stay, was examined with a multivariate logistic regression analyses. Of the 10,099 URS patients with BMI data, 17.4% were obese and 2.2% were super obese. Overall, 86.7% patients were stone free and 16.8% required retreatment. Higher BMI was associated with lower stone-free rates, and any deviation from normal weight was associated with higher retreatment rates. In multivariate analysis controlling for several variables including stone size, the association between BMI and lower stone-free rates with higher retreatment rates persisted. Intraoperative complications occurred in 518 (5.1%) patients, and 343 (3.4%) experienced a postoperative complication. Postoperative complications were more frequent in the underweight and super obese subjects, and there was no relationship between BMI and intraoperative complications. Although URS for stone disease was found to be an overall safe procedure for obese and super obese patients, efficacy of the procedure may be lower compared with normal-weight subjects and higher retreatment rates may be necessary.

Effectiveness of rotatory and reciprocating movements in root canal filling material removal

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Emmanuel João Nogueira Leal SILVA

2015-01-01

Full Text Available The purpose of this study was to compare the efficacy of reciprocating and rotary techniques for removing gutta-percha and sealer from root canals. Forty straight and oval single-rooted premolars were prepared up to size 30, filled with gutta-percha and sealer, and then randomly allocated to two experimental retreatment groups: ProTaper Retreatment System (PTRS and WaveOne System (WS. Procedural errors, time of retreatment and apically extruded material were recorded for all the roots. The roots were radiographed after retreatment. The percentage of residual material was calculated using image analysis software. The data were analyzed by Kolmogorov-Smirnov and t tests, with a significance level set at 5%. No system completely removed the root filling material from the root canal. No significant differences were observed between the systems, in terms of residual filling material in any tested third (p > 0.05. WS was faster in removing filling material than PTRS (p< 0.05. Extrusion was observed in 4 cases in PTRS and in 5 cases in WS. No procedural errors were observed in either group. It can be concluded that although no differences were observed in the efficacy of PTRS and WS for removing root filling material, WS was faster than PTRS.

Postoperative Pain after Root Canal Treatment: A Prospective Cohort Study

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M. Gotler

2012-01-01

Full Text Available Aim. To evaluate the incidence and severity of postendodontic treatment pain (PEP subsequent to root canal treatment (RCT in vital and necrotic pulps and after retreatment. Methodology. A prospective study. Participants were all patients (=274 who underwent RCT in teeth with vital pulp, necrotic pulp, or vital pulp that had been treated for symptomatic irreversible pulpitis or who received root canal retreatment, by one clinician, during an eight-month period. Exclusion criteria were swelling, purulence, and antibiotic use during initial treatment. A structured questionnaire accessed age, gender, tooth location, and pulpal diagnosis. Within 24 h of treatment, patients were asked to grade their pain at 6 and 18 hours posttreatment, using a 1–5 point scale. Results. RCT of teeth with vital pulp induced a significantly higher incidence and severity of PEP (63.8%; 2.46 ± 1.4, resp. than RCT of teeth with necrotic pulp (38.5%; 1.78 ± 1.2, resp. or of retreated teeth (48.8%; 1.89 ± 1.1, resp.. No statistical relation was found between type of pain (spontaneous or stimulated and pulp condition. Conclusion. RCT of teeth with vital pulp induced a significantly higher incidence and intensity of PEP compared to teeth with necrotic pulp or retreated teeth.

Lifestyle Decreases Risk Factors for Cardiovascular Diseases

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Slavíček, Jaroslav; Kittnar, Otomar; Fraser, Gary E.; Medová, Eva; Konečná, Jana; Žižka, Robert; Dohnalová, Alena; Novák, Vladimír

2009-01-01

Summary The morbidity and mortality of the cardiovascular diseases is high in the developed countries. The lifestyle changes are capable to decrease it by 50%. The aim of the present study was to measure the parameters of some risk factors before and after a one-week NEW START rehabilitative retreat. 1,349 volunteers, 320 men, 1,029 woman, mean age 51±14.5 (SD) years participated in 30 rehabilitative retreats from 1999–2006 in the Czech Republic, using a low-fat, low-energy, lacto-ovo-vegetarian diet and exercise, in a stress-free environment. Body weight, height, BMI, blood pressure, heart rate, serum cholesterol and blood glucose were measured. Body weight decreased in 1,223 measured persons from 71.2±14.38 (SD) to 70.6±14.02 kg (pSeventh-day Adventists than in controls who never observed the diet and avail the lifestyle programs. The parameters were nonsignificantly changed one year after finishing the retreat in the sample of 68 persons showing the positive effect of retreats. Our results showed, that the intake of a low-fat, low-energy diet, over the course of one week in a stress-free environment, had positive impact on the risk factors of cardiovascular diseases. PMID:19256282

Clinical results of PRK touch-up using Chiron/Technolas Keracor 116 excimer laser

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Davidian, Mary E.; Keates, Richard H.; Ren, Qiushi

1995-05-01

Regression of effect as well as undercorrection are well established complications of excimer photorefractive keratectomy for the correction of myopia. In thirteen eyes initially treated with the VISX Taunton excimer laser and then retreated with the Chiron Technolas laser, the minimum follow-up time was six months. The mean postoperative refraction at six months was -0.442 +/- 0.996 D (diopters), significantly different from the pretreatment mean of -1.904 +/- 1.297 D. At six months after retreatment (10/13 eyes) 76.9% had an uncorrected visual acuity greater than or equal to 20/40 and (10/13 eyes) 76.9% were within 1 diopter of emmetropia. Only one eye had a significant increase in postoperative haze. The results of this study indicate that the majority of photorefractive keratectomy regressions and undercorrections can be successfully retreated.

ESTIMATION OF THE WANDA GLACIER (SOUTH SHETLANDS) SEDIMENT EROSION RATE USING NUMERICAL MODELLING

OpenAIRE

Kátia Kellem Rosa; Rosemary Vieira; Jefferson Cardia Simões

2013-01-01

Glacial sediment yield results from glacial erosion and is influenced by several factors including glacial retreat rate, ice flow velocity and thermal regime. This paper estimates the contemporary subglacial erosion rate and sediment yield of Wanda Glacier (King George Island, South Shetlands). This work also examines basal sediment evacuation mechanisms by runoff and glacial erosion processes during the subglacial transport. This is small temperate glacier that has seen retreating for the l...

Landforms, sediments and dates to constrain rates and style of marine-influenced ice sheet decay; the BRITICE-CHRONO project.

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Clark, Chris

2014-05-01

Uncertainty exists regarding the future mass of the Antarctic and Greenland ice sheets and how they will respond to forcings from sea level, and atmospheric and ocean temperatures. If we want to know more about the mechanisms and rate of change of shrinking ice sheets, then why not examine an ice sheet that has fully disappeared and track its retreat through time? If achieved in enough detail such information on ice retreat could be a data-rich playground for improving the next breed of numerical ice sheet models to be used in ice and sea level forecasting. We regard that the last British-Irish Ice Sheet is a good target for this work, on account of its small size, density of information and with its numerous researchers already investigating it. Geomorphological mapping across the British Isles and the surrounding continental shelf has revealed the nature and distribution of glacial landforms. Here we demonstrate how such data have been used to build a pattern of ice margin retreat. The BRITICE-CHRONO consortium of Quaternary scientists and glaciologists, are now working on a project running from 2012 - 2017 to produce an ice sheet wide database of geochronometric dates to constrain and then understand ice margin retreat. This is being achieved by focusing on 8 transects running from the continental shelf edge to a short distance (10s km) onshore and acquiring marine and terrestrial samples for geochronometric dating. The project includes funding for 587 radiocarbon, 140 OSL and 158 TCN samples for surface exposure dating; with sampling accomplished by two research cruises and 16 fieldwork campaigns. Results will reveal the timing and rate of change of ice margin recession for each transect, and combined with existing landform and dating databases, will be used to build an ice sheet-wide empirical reconstruction of retreat. Simulations using two numerical ice sheet models, fitted against the margin data, will help us understand the nature and significance of sea

Palliative splenic irradiation in primary and post PV/ET myelofibrosis: outcomes and toxicity of three radiation schedules

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Mario Federico

2009-05-01

Full Text Available Splenectomy and splenic irradiation (SI are the sole treatment modalities to control drug resistant splenomegaly in patients with myelofibrosis (MF. SI has been used in poor surgical candidates but optimal total dose and fractionation are unclear. We retrospectively reviewed 14 MF patients with symptomatic splenomegaly. Patients received a median of 10 fractions in two weeks. Fraction size ranged from 0.2-1.4 Gy, and total dose varied from 2-10.8 Gy per RT course. Overall results indicate that 81.8% of radiation courses achieved a significant spleen reduction. Splenic pain relief and gastrointestinal symptoms reduction were obtained in 94% and 91% of courses, respectively. Severe cytopenias occurred in 13% of radiation courses. Furthermore patients were divided in three groups according to the radiation dose they received: 6 patients in the low-dose group (LDG received a normalized dose of 1.67 Gy; 4 patients in the intermediate-dose group (IDG received a normalized dose 4.37 Gy; the remaining 4 patients in the high-dose group (HDG received a normalized dose of 9.2 Gy. Subgroup analysis showed that if no differences in terms of treatment’s efficacy were seen among dose groups, hematologic toxicity rates distributed differently. Severe cytopenias occurred in 50% of courses in the HDG, and in the 14.3% and in 0% of the IDG and LDG respectively. Spleen reduction and pain relief lasted for a median of 5.5 months in all groups. Due to the efficacy and tolerability of the low-dose irradiation 4 patients from the LDG and IDG were retreated and received on the whole 12 RT courses. Multiple retreatments did not show decremental trends in terms of rates of response to radiation nor in terms of duration of clinical response. Moreover, retreatment courses did not cause an increased rate of adverse effects and none of the retreated patients experienced severe hematologic toxicities. The average time of clinical benefit in retreated patients was much longer

Sea-ice indicators of polar bear habitat

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H. L. Stern

2016-09-01

Full Text Available Nineteen subpopulations of polar bears (Ursus maritimus are found throughout the circumpolar Arctic, and in all regions they depend on sea ice as a platform for traveling, hunting, and breeding. Therefore polar bear phenology – the cycle of biological events – is linked to the timing of sea-ice retreat in spring and advance in fall. We analyzed the dates of sea-ice retreat and advance in all 19 polar bear subpopulation regions from 1979 to 2014, using daily sea-ice concentration data from satellite passive microwave instruments. We define the dates of sea-ice retreat and advance in a region as the dates when the area of sea ice drops below a certain threshold (retreat on its way to the summer minimum or rises above the threshold (advance on its way to the winter maximum. The threshold is chosen to be halfway between the historical (1979–2014 mean September and mean March sea-ice areas. In all 19 regions there is a trend toward earlier sea-ice retreat and later sea-ice advance. Trends generally range from −3 to −9 days decade−1 in spring and from +3 to +9 days decade−1 in fall, with larger trends in the Barents Sea and central Arctic Basin. The trends are not sensitive to the threshold. We also calculated the number of days per year that the sea-ice area exceeded the threshold (termed ice-covered days and the average sea-ice concentration from 1 June through 31 October. The number of ice-covered days is declining in all regions at the rate of −7 to −19 days decade−1, with larger trends in the Barents Sea and central Arctic Basin. The June–October sea-ice concentration is declining in all regions at rates ranging from −1 to −9 percent decade−1. These sea-ice metrics (or indicators of habitat change were designed to be useful for management agencies and for comparative purposes among subpopulations. We recommend that the National Climate Assessment include the timing of sea-ice retreat and advance in

Sarcocystis nesbitti causes acute, relapsing febrile myositis with a high attack rate: description of a large outbreak of muscular sarcocystosis in Pangkor Island, Malaysia, 2012.

OpenAIRE

Claire M Italiano; Kum Thong Wong; Sazaly AbuBakar; Yee Ling Lau; Norlisah Ramli; Sharifah Faridah Syed Omar; Maria Kahar Bador; Chong Tin Tan

2014-01-01

BACKGROUND: From the 17th to 19th January 2012, a group of 92 college students and teachers attended a retreat in a hotel located on Pangkor Island, off the west coast of Peninsular Malaysia. Following the onset of symptoms in many participants who presented to our institute, an investigation was undertaken which ultimately identified Sarcocystis nesbitti as the cause of this outbreak. METHODOLOGY/PRINCIPAL FINDINGS: All retreat participants were identified, and clinical and epidemiological i...

Low post-glacial rebound rates in the Weddell Sea due to Late Holocene ice-sheet readvance.

OpenAIRE

Bradley, S.L.; Hindmarsh, R.C.A.; Whitehouse, P.L.; Bentley, M.J.; King, M.A.

2015-01-01

Many ice-sheet reconstructions assume monotonic Holocene retreat for the West Antarctic Ice Sheet, but an increasing number of glaciological observations infer that some portions of the ice sheet may be readvancing, following retreat behind the present-day margin. A readvance in the Weddell Sea region can reconcile two outstanding problems: (i) the present-day widespread occurrence of seemingly stable ice streams grounded on beds that deepen inland; and (ii) the inability of models of glacial...

Eficiency of different doses of rituximab in rheumatoid arthritis.

Science.gov (United States)

Mena-Vázquez, Natalia; Manrique-Arija, Sara; Ureña-Garnica, Inmaculada; Romero-Barco, Carmen M; Jiménez-Núñez, Francisco G; Coret, Virginia; Irigoyen-Oyarzábal, María Victoria; Fernández-Nebro, Antonio

2016-01-01

Evaluate the effectiveness, cost and safety of rituximab in patients with rheumatoid arthritis (RA) depending on the dose used. Retrospective observational study conducted on 52 patients with RA treated with at least one dose of rituximab for 135.3 patient-years were included. Three treatment groups were obtained: (G1) First course and following two 1g infusions separated by 15 days; (G2) First course 2 infusions of 1g followed by 2 infusions of 500mg; (G3) First course and followed by 2 infusions of 500mg separated by 15 days. Re-treatments were administered on-demand according to the clinical activity. The retention time (Log-Rank), retreats and adverse events rates (incidence rate ratio) and treatment costs per patient-month of rituximab were analysed by groups. Group 2 showed a better cost-effectiveness ratio than group 1, as it was associated with a longer retention of rituximab (mean [95% CI] 65.7 [60.8 to 70.7] months vs 33.5 [22.7 to 44.3]; P<.001) and a lower rate of severe adverse events with only a slight increase in the rate of retreatment (courses/patient-year [95% CI] 1.66 [1.39 to 1.93] vs. 1.01 [0.69 to 1.34]; P=.005), and in the costs (median/patient-month, €484.89 vs. €473.45). Although group 3 was €41.20/patient-month cheaper than group 2, it was associated with a higher rate of re-treatments and shorter retention of rituximab (P<.001). The use of full-dose rituximab at onset, followed by reduced doses in successive courses administered on-demand retreatment may be the most cost-effective option. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

Glacier Change, Supraglacial Debris Expansion and Glacial Lake Evolution in the Gyirong River Basin, Central Himalayas, between 1988 and 2015

Directory of Open Access Journals (Sweden)

Sheng Jiang

2018-06-01

Full Text Available Himalayan glacier changes in the context of global climate change have attracted worldwide attention due to their profound cryo-hydrological ramifications. However, an integrated understanding of the debris-free and debris-covered glacier evolution and its interaction with glacial lake is still lacking. Using one case study in the Gyirong River Basin located in the central Himalayas, this paper applied archival Landsat imagery and an automated mapping method to understand how glaciers and glacial lakes interactively evolved between 1988 and 2015. Our analyses identified 467 glaciers in 1988, containing 435 debris-free and 32 debris-covered glaciers, with a total area of 614.09 ± 36.69 km2. These glaciers decreased by 16.45% in area from 1988 to 2015, with an accelerated retreat rate after 1994. Debris-free glaciers retreated faster than debris-covered glaciers. As a result of glacial downwasting, supraglacial debris coverage expanded upward by 17.79 km2 (24.44%. Concurrent with glacial retreat, glacial lakes increased in both number (+41 and area (+54.11%. Glacier-connected lakes likely accelerated the glacial retreat via thermal energy transmission and contributed to over 15% of the area loss in their connected glaciers. On the other hand, significant glacial retreats led to disconnections from their proglacial lakes, which appeared to stabilize the lake areas. Continuous expansions in the lakes connected with debris-covered glaciers, therefore, need additional attention due to their potential outbursts. In comparison with precipitation variation, temperature increase was the primary driver of such glacier and glacial lake changes. In addition, debris coverage, size, altitude, and connectivity with glacial lakes also affected the degree of glacial changes and resulted in the spatial heterogeneity of glacial wastage across the Gyirong River Basin.

Euro directives retreat to fight another day

International Nuclear Information System (INIS)

Anon.

1993-01-01

The European Community's proposal to introduce common-carriage rules sent a shiver through most of Europe's gas industry. While the newly-appointed European Commission is rethinking its third-party access (TPA) legislation, under a wide-ranging review of the Community's role, the movement towards more open markets has slowed but not stopped. This article looks at how the EC process of gas market liberalisation has progressed during the traumatic stresses of Maastricht ratification and at how it is viewed by the industry. (author)

Singapore's Global Schoolhouse Strategy: Retreat or Recalibration?

Science.gov (United States)

Waring, Peter

2014-01-01

In 2002 a high-level economic review committee recommended that Singapore position itself as a "global schoolhouse". An ambitious target was set to attract 150,000 international students to Singapore by 2015 and to lift the education sector's contribution to GDP from 1.9% to 5% in the same timeframe. The global schoolhouse was viewed as…

Nostalgia: retreat or support in difficult times?

Science.gov (United States)

Batcho, Krystine Irene

2013-01-01

The relationship between nostalgia and coping during difficult times was explored in 2 empirical studies. In the first, 80 undergraduates, 60 women and 20 men, completed the Nostalgia Inventory, a measure of nostalgia proneness, the COPE Inventory, a dispositional measure of strategies for coping with stressful events, and the Childhood Survey, a survey of impressions of childhood experiences. Nostalgia proneness correlated with use of adaptive coping, including emotional social support, expressing emotions, turning to religion, and suppressing competing activities, and did not correlate with escapist or avoidance strategies, including denial, behavioral disengagement, and substance abuse. Nostalgia proneness was related positively to favorable emotional and behavioral childhood experiences and did not correlate with adverse experiences. Favorable impressions of childhood correlated positively with adaptive coping strategies and inversely with dysfunctional ones, whereas unfavorable childhood experiences correlated positively with dysfunctional coping. Regression analyses suggested that the relationship between nostalgia proneness and certain coping strategies may be mediated in part by childhood experiences. In a second study, 100 undergraduates, 86 women and 14 men, completed the Nostalgia Inventory, recalled autobiographical memories that illustrated how childhood is either special or similar to their present life, and rated their likely use of strategies in dealing with 2 hypothetical problems. Nostalgia proneness correlated with emotional and instrumental social coping and with the goal-directed strategies of planning, taking action, and positive reframing. Further research is recommended to explore the role of childhood memories in coping and to identify mechanisms that mediate the relationship between nostalgia and coping.

Technico-Economical study of retreated uranium reenrichment

International Nuclear Information System (INIS)

Patillon, L.

1985-03-01

Spent fuel from nuclear power plants is reprocessed at La Hague reprocessing plant in France. Recovered and stored reprocessed uranium has an energy potential unutilized so far. A modelisation is proposed in this paper for evaluating the economic interest reprocessed uranium reenrichment for using it again in a power plant. After briefly recalling the fuel cycle in light water reactors and reprocessed uranium specificities, a mathematical model for multi-isotope enrichment gives a differential system governing isotopic separation. Different solutions are proposed and compared. A. de la Garza analytical model's is retained. An economic value is attributed to reprocessed uranium. Results are presented as curves for determining the sensitivity of this value to simulation parameters (natural uranium cost, enrichment required by the electricity board etc.) [fr

Flowfield Characteristics on a Retreating Rotor Blade

Science.gov (United States)

2015-12-03

Rotating Disk, IMECE2013 ASME 2013 International Mechanical Engineering Congress & Exposition. 21-NOV-13, . : , Michael Mayo, Nicholas Motahari...Number: Discipline Brandon Liberi 0.00 Jackson Merkl 0.00 Vaibhav Kumar 0.00 Nicholas Motahari 0.00 Ryan McMullen 0.00 0.00 5 NAME Total Number...horizontal and vertical pixel position of the far ends of the rotor hub and performing an inverse tan operation. Davis 7.2 software by LaVision was used to

Tuberculosis treatment delivery in high burden settings: does patient choice of supervision matter?

Science.gov (United States)

Kironde, S; Meintjies, M

2002-07-01

The Northern Cape Province, Republic of South Africa. To determine the effect of patient choice of treatment delivery option on the treatment outcomes of tuberculosis (TB) patients in a high burden setting under actual programme conditions. Cohort study involving 769 new and retreatment TB patients recruited from 45 randomly selected clinics. Patients were interviewed and subsequent follow-up was done through regular visits to the clinics to check progress through formal health records. There was a statistically significant difference (P < 0.001) between the treatment outcome of new patients (70% successful) and re-treatment patients (54% successful). Direct observation of treatment (DOT) was found to have no effect on the treatment outcome of new patients (P = 0.875), but re-treatment patients were found to fare better with than without DOT (OR 14.2, 95% CI 4.18-53.14, P < 0.001). The results obtained for new patients are similar to those of two recent randomised controlled trials on DOT. This study revealed that for new patients, undue emphasis on universal DOT might be unnecessary. It would perhaps be more beneficial to target supervision at those patients who are most likely to benefit from it (i.e., re-treatment patients). This is of particular relevance in high burden, resource-limited settings where universal DOT for all TB patients is generally unfeasible.

Management of Renal Tumors by Image-Guided Radiofrequency Ablation: Experience in 105 Tumors

International Nuclear Information System (INIS)

Breen, David J.; Rutherford, Elizabeth E.; Stedman, Brian; Roy-Choudhury, Shuvro H.; Cast, James E. I.; Hayes, Matthew C.; Smart, Christopher J.

2007-01-01

Aims. In this article we present our experience with radiofrequency ablation (RFA) in the treatment of 105 renal tumors. Materials and Methods. RFA was performed on 105 renal tumors in 97 patients, with a mean tumor size of 32 mm (11-68 mm). The mean patient age was 71.7 years (range, 36-89 years). The ablations were carried out under ultrasound (n = 43) or CT (n = 62) guidance. Imaging follow-up was by contrast-enhanced CT within 10 days and then at 6-monthly intervals. Multivariate analysis was performed to determine variables associated with procedural outcome. Results. Eighty-three tumors were completely treated at a single sitting (79%). Twelve of the remaining tumors were successfully re-treated and a clinical decision was made not to re-treat seven patients. A patient with a small residual crescent of tumor is under follow-up and may require further treatment. In another patient, re-treatment was abandoned due to complicating pneumothorax and difficult access. One patient is awaiting further re-treatment. The overall technical success rate was 90.5%. Multivariate analysis revealed tumor size to be the only significant variable affecting procedural outcome. (p = 0.007, Pearson χ 2 ) Five patients had complications. There have been no local recurrences. Conclusion. Our experience to date suggests that RFA is a safe and effective, minimally invasive treatment for small renal tumors

Age and evolution of diachronous erosion surfaces in the Amazon: Combining (U-Th)/He and cosmogenic 3He records

Science.gov (United States)

Monteiro, H. S.; Vasconcelos, P. M. P.; Farley, K. A.; Lopes, C. A. M.

2018-05-01

(U-Th)/He geochronology of two weathered plateaus in the Carajás Mountains, Pará, Brazil, reveals a history of weathering spanning from ca. 80 Ma to the present for this high elevation (∼720 m) land surface. Cosmogenic 3He measurements of hematite pebbles and blocks cemented onto the plateaus at two sites, N1 and S11D, yield erosion rates as low as 0.09 and 0.08 m Ma-1, respectively. Thus, these results confirm that the plateau surfaces are nearly immune to physical erosion for tens of millions of years. (U-Th)/He geochronology of ferruginous duricrusts blanketing the low elevation (250-100 m) plains surrounding the Carajás Mountains yield results consistently younger than ∼10 Ma. The geochronology results also reveal that the low elevation plain is diachronous, becoming progressively younger towards the receding plateaus. The spatial distribution of (U-Th)/He ages permits reconstruction of the history of scarp retreat for the Carajás landscape, showing that scarp retreat along major river valleys may have been as fast as 20 km Ma-1 during tectonically active and humid periods in the Cenozoic. The cessation of scarp retreat at some sites suggests that metamorphosed banded iron-formations and quartzites provide effective barriers to retreating escarpments, helping to preserve some of the oldest continuously exposed land surfaces on Earth.

Teen Ambassador Leadership Kit (TALK

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Donna R. Gillespie

2012-12-01

Full Text Available Teen Ambassador Leadership Kit, (TALK, is an annual weekend retreat designed for teens interested in promoting and marketing 4-H in their communities. TALK organizers felt teens would benefit from an intensive weekend retreat focused on communication. TALK produces a network of educated and excited 4-H teens that are available to help with 4-H promotion and marketing. Participants arrive on Friday evening for team building activities, on Saturday they participate in one of the workshops offered and on Sunday morning each workshop group has the opportunity to share their completed projects and what they learned. At the conclusion of the retreat, teens are designated "County 4-H Ambassadors" and certificates of completion, professional business cards and polo shirts are presented. The TALK teen participants return home to share what they learned with their local county 4-H staff and help promote and market 4-H in their communities.

Deglacial History and Paleoceanography of the Umanak System, West Greenland

DEFF Research Database (Denmark)

Sheldon, Christina; Jennings, Anne; Andrews, John

2012-01-01

A record of Greenland Ice Sheet (GIS) and ice-stream history, ice-sheet ocean interactions and paleoclimate from the Last Glacial Maximum to present is preserved in the sediments of the Umanak fjord, shelf trough and trough mouth fan system of central West Greenland. The objective of this study....... This evidence of Atlantic Water carried in the WGC precedes lithological evidence of ice stream retreat from the shelf edge (an influx of coarse IRD beginning 62 cm above the first Atlantic Water assemblage) indicating the presence of the WGC at the shelf edge prior to initial deglaciation. Both the slope...... is to document the timing and rate of ice retreat and the role of the West Greenland Current (WGC) in initiating or sustaining ice retreat. During cruise JR175 of the UK ship RRS James Clark Ross in 2009, sediment cores and geophysical data were collected from the Umanak System to document the glacial history...

Decadal-scale climate drivers for glacial dynamics in Glacier National Park, Montana, USA

Science.gov (United States)

Pederson, Gregory T.; Fagre, Daniel B.; Gray, Stephen T.; Graumlich, Lisa J.

2004-06-01

Little Ice Age (14th-19th centuries A.D.) glacial maxima and 20th century retreat have been well documented in Glacier National Park, Montana, USA. However, the influence of regional and Pacific Basin driven climate variability on these events is poorly understood. We use tree-ring reconstructions of North Pacific surface temperature anomalies and summer drought as proxies for winter glacial accumulation and summer ablation, respectively, over the past three centuries. These records show that the 1850's glacial maximum was likely produced by ~70 yrs of cool/wet summers coupled with high snowpack. Post 1850, glacial retreat coincides with an extended period (>50 yr) of summer drought and low snowpack culminating in the exceptional events of 1917 to 1941 when retreat rates for some glaciers exceeded 100 m/yr. This research highlights potential local and ocean-based drivers of glacial dynamics, and difficulties in separating the effects of global climate change from regional expressions of decadal-scale climate variability.

Proceedings of the Annual Meeting of the Eastern Snow Conference (47th) Held in Bangor, Maine on 7-8 June 1990

Science.gov (United States)

1990-06-01

and associated expenses. Runner -up papers; a one-year free membership in ESC, an ESC President’s certificate and a $100.00 cash prize. This year the...EXTENT *** 1843 1846 RATE OF RETREAT (1721-1953) (M YR-’) **** 4.7 4.7 RATE OF RETREAT (1938-1960) (M YR-) 28 19 * KITE AND REID, 1977 •* PATERSON AND...Water Resources Branch, Water Survey of Canada, Canada. Kite , G.W. and Reid, L.A. (1977) Volumetric change of the Athabasca Glacier over the last 100

Cobra-Gruppens besøg i Bregnerød

DEFF Research Database (Denmark)

Baumeister, Ruth

2014-01-01

This article describes the Cobra-meeting in Bregnerød. It exemplifies the interior painting of the weekend retreat of the Royal academy´s architecture students and contextualizes the event within the European postwar discourse of a synthesis of the arts.......This article describes the Cobra-meeting in Bregnerød. It exemplifies the interior painting of the weekend retreat of the Royal academy´s architecture students and contextualizes the event within the European postwar discourse of a synthesis of the arts....

Dendrochronology and late Holocene history of Bering piedmont glacier, Alaska

Science.gov (United States)

Wiles, G.C.; Post, A.; Muller, E.H.; Molnia, B.F.

1999-01-01

Fluctuations of the piedmont lobe of Bering Glacier and its sublobe Steller Glacier over the past two millennia are reconstructed using 34 radiocarbon dates and tree-ring data from 16 sites across the glaciers' forelands. The general sequence of glacial activity is consistent with well-dated fluctuations of tidewater and land-terminating glaciers elsewhere along the Gulf of Alaska. Extensive forested areas along 25 km of the Bering ice margin were inundated by glacio-lacustrine and glacio-fluvial sediments during a probable ice advance shortly before 500 cal yr A.D. Regrowth of forests followed the retreating ice as early as the 7th century A.D., with frequent interruptions of tree growth due to outwash aggradation. Forests overrun by ice and buried in outwash indicate readvance about 1080 cal yr A.D. Retreat followed, with ice-free conditions maintained along the distal portions of the forefield until the early 17th century after which the ice advanced to within a few kilometers of its outer Neoglacial moraine. Ice reached this position after the mid-17th century and prior to 200 yr ago. Since the early 20th century, glacial retreat has been punctuated by periodic surges. The record from forests overrun by the nonsurging Steller Lobe shows that this western ice margin was advancing by 1250 A.D., reaching near its outer moraine after 1420 cal yr A.D. Since the late 19th century, the lobe has dominantly retreated.

Improved inflammatory activity with peginterferon alfa-2b maintenance therapy in non-cirrhotic prior non-responders: a randomized study.

Science.gov (United States)

Poynard, Thierry; Bruix, Jordi; Schiff, Eugene R; Diago, Moises; Berg, Thomas; Moreno-Otero, Ricardo; Lyra, Andre C; Carrilho, Flair; Griffel, Louis H; Boparai, Navdeep; Jiang, Ruiyun; Burroughs, Margaret; Brass, Clifford A; Albrecht, Janice K

2013-03-01

Therapeutic options for patients failing hepatitis C retreatment are limited. EPIC(3) included a prospective trial assessing long-term peginterferon alfa-2b (PegIFNα-2b) maintenance therapy in patients with METAVIR fibrosis scores (MFS) of F2 or F3 who previously failed hepatitis C retreatment. Patients with F2/F3 MFS who failed retreatment were randomized to PegIFNα-2b (0.5 μg/kg/week, n=270) or observation (n=270) for 36 months. Blinded liver biopsies obtained before retreatment and after maintenance therapy were evaluated using MFS and activity scores, and confirmatory testing was performed using FibroTest and ActiTest. In total, 348 patients had paired biopsies: 192 patients had missing post-treatment biopsies and were considered as having no change in fibrosis/activity scores. In total, 16% of patients receiving PegIFNα-2b and 11% of observation patients had improvement in MFS (p=0.32). More PegIFNα-2b than observation patients had improvement in activity score (20% vs. 9%; p 2.5 years, improvement in MFS or activity score was more common with PegIFNα-2b than observation (21% vs. 14%, p=0.08 and 26% vs. 10%, p 2.5 years. Both FibroTest and ActiTest were significantly improved during maintenance therapy. Copyright © 2012 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Bluff evolution along coastal drumlins: Boston Harbor Islands, Massachusetts

Science.gov (United States)

Himmelstoss, E.A.; FitzGerald, D.M.; Rosen, P.S.; Allen, J.R.

2006-01-01

A series of partially drowned drumlins forms the backbone of the inner islands within Boston Harbor. The shoreline of these rounded glacial deposits is composed of actively retreating bluffs formed by continual wave attack. Comparisons of bluffs reveal variability in their height and lateral extent, as well as in the dominant mechanism causing their retreat. Two processes are responsible for bluff erosion and yield distinct bluff morphologies: (1) wave attack undercuts the bluff and causes episodic slumping, yielding planar bluff slopes, and (2) subaerial processes such as rainfall create irregular slopes characterized by rills and gullies. We propose a model of drumlin bluff evolution that is based on processes of erosion and physical characteristics such as bluff height, slope morphology, and the orientation of the bluff with respect to the long axis of the drumlin and its topographic crest. The four phases of drumlin bluff evolution consist of (1) initial formation of bluff, with retreat dominated by wave notching and slumping processes; (2) rill and gully development as bluff heights exceed 10 m and slumped sediment at bluff base inhibits wave attack; (3) return of wave notching and slumping as bluff heights decrease; and (4) final development of boulder retreat lag as last remnants of drumlin are eroded by wave action. These phases capture the important physical processes of drumlin evolution in Boston Harbor and could apply to other eroding coastal drumlin deposits.

Zooming in and out: Scale dependence of extrinsic and intrinsic factors affecting salt marsh erosion

Science.gov (United States)

Wang, Heng; van der Wal, Daphne; Li, Xiangyu; van Belzen, Jim; Herman, Peter M. J.; Hu, Zhan; Ge, Zhenming; Zhang, Liquan; Bouma, Tjeerd J.

2017-07-01

Salt marshes are valuable ecosystems that provide important ecosystem services. Given the global scale of marsh loss due to climate change and coastal squeeze, there is a pressing need to identify the critical extrinsic (wind exposure and foreshore morphology) and intrinsic factors (soil and vegetation properties) affecting the erosion of salt marsh edges. In this study, we quantified rates of cliff lateral retreat (i.e., the eroding edge of a salt marsh plateau) using a time series of aerial photographs taken over four salt marsh sites in the Westerschelde estuary, the Netherlands. In addition, we experimentally quantified the erodibility of sediment cores collected from the marsh edge of these four marshes using wave tanks. Our results revealed the following: (i) at the large scale, wind exposure and the presence of pioneer vegetation in front of the cliff were the key factors governing cliff retreat rates; (ii) at the intermediate scale, foreshore morphology was partially related to cliff retreat; (iii) at the local scale, the erodibility of the sediment itself at the marsh edge played a large role in determining the cliff retreat rate; and (iv) at the mesocosm scale, cliff erodibility was determined by soil properties and belowground root biomass. Thus, both extrinsic and intrinsic factors determined the fate of the salt marsh but at different scales. Our study highlights the importance of understanding the scale dependence of the factors driving the evolution of salt marsh landscapes.

The impact of mindfulness on leadership effectiveness in a health care setting: a pilot study.

Science.gov (United States)

Wasylkiw, Louise; Holton, Judith; Azar, Rima; Cook, William

2015-01-01

The purpose of this paper is to examine the impact of mindfulness awareness practice (MAP) on mid-level health-care managers' leadership. In total, 11 mid-level health-care managers in eastern Canada took part in an intensive weekend retreat and a follow-up webinar on mindfulness awareness. Perceived stress and leadership effectiveness were assessed pre- and post-intervention (i.e. four and eight weeks). A control group (n=10) also completed the same measures twice. Additionally, informants (n=28) provided assessments of participants' leadership pre- and post-intervention. Follow-up interviews were carried out with eight participants 12-16 weeks post-intervention. In comparison to controls, retreat participants showed significant increases in mindfulness and corresponding decreases in stress that were sustained across eight weeks post-retreat; retreat participants reported significant positive changes in their leadership effectiveness that were corroborated by informants. Qualitative data, however, suggest that sustaining a mindfulness practice presents significant challenges to middle managers in a health care setting. The findings are useful to management working in health services that are plagued by increasing demands and changes. Despite the small sample and lack of random assignment, the pilot data support the efficacy of MAP in improving leadership. Little empirical research supports the claim that MAP enhances leadership. The present study employed a mixed methods approach to address this gap and demonstrates the potential benefits of MAP among mid-level managers.

Modeling the response of Northwest Greenland to enhanced ocean thermal forcing and subglacial discharge

Science.gov (United States)

Morlighem, M.; Wood, M.; Seroussi, H. L.; Bondzio, J. H.; Rignot, E. J.

2017-12-01

Glacier-front dynamics is an important control on Greenland's ice mass balance. Warm and salty Atlantic water, which is typically found at a depth below 200-300 m, has the potential to trigger ice-front retreats of marine-terminating glaciers, and the corresponding loss in resistive stress leads to glacier acceleration and thinning. It remains unclear, however, which glaciers are currently stable but may retreat in the future, and how far inland and how fast they will retreat. Here, we quantify the sensitivity and vulnerability of marine-terminating glaciers along the Northwest coast of Greenland (from 72.5° to 76°N) to ocean forcing using the Ice Sheet System Model (ISSM), and its new ice front migration capability. We rely on the ice melt parameterization from Rignot et al. 2016, and use ocean temperature and salinity from high-resolution ECCO2 simulations on the continental shelf to constrain the thermal forcing. The ice flow model includes a calving law based on a Von Mises criterion. We investigate the sensitivity of Northwest Greenland to enhanced ocean thermal forcing and subglacial discharge. We find that some glaciers, such as Dietrichson Gletscher or Alison Gletscher, are sensitive to small increases in ocean thermal forcing, while others, such as Illullip Sermia or Qeqertarsuup Sermia, are very difficult to destabilize, even with a quadrupling of the melt. Under the most intense melt experiment, we find that Hayes Gletscher retreats by more than 50 km inland into a deep trough and its velocity increases by a factor of 10 over only 15 years. The model confirms that ice-ocean interactions are the triggering mechanism of glacier retreat, but the bed controls its magnitude. This work was performed at the University of California Irvine under a contract with the National Aeronautics and Space Administration, Cryospheric Sciences Program (#NNX15AD55G), and the National Science Foundation's ARCSS program (#1504230).

Variación diaria de la temperatura corporal en dos especies de lagartos nocturnos (Squamata, Gekkonidae, Homonota con comentarios sobre el uso de refugios

Directory of Open Access Journals (Sweden)

Cruz, Félix B.

2004-09-01

Full Text Available Poco es lo que se conoce sobre la variación de la temperatura corporal de lagartos nocturnos. Se sabe que algunos lagartos nocturnos termorregulan durante el día. El tamaño corporal y el comportamiento, a su vez, pueden estar relacionados con la inercia térmica. Individuos de Homonota borelli y H. darwini fueron expuestos a tres situaciones, a refugios cálidos (la temperatura nunca fue menor a los 34 ºC, b refugios con una temperatura inferior a los 28-30 ºC, y c se les permitió escoger entre cada una de las opciones anteriores. La temperatura corporal en general y el patrón diario fueron similares en ambas especies siendo más altas durante el día. Cuando los lagartos eligieron los refugios, se observaron diferencias entre las especies, H. borelli usó más los refugios con fuente de calor en tanto que H. darwini usó refugios sin fuente de calor. El tamaño corporal y la distribución geográfica podrían estar relacionados con las diferencias observadas. Very little is known about diel variation in body temperature among nocturnal lizards. Some nocturnal lizards thermoregulate during the day, and body size plus behaviour may be related to the amount of thermal inertia. Lizards of the species Homonota borelli and H. darwini were either exposed to three different situations a a heated retreat site (never below than 34 º C, b a retreat with a temperature lower than 28-30 º C, and c where lizards were allowed to choose between a warm or a cool retreat. Body temperatures and diel pattern were similar for both species. Body temperatures were higher during the day. When lizards choose for retreats, differences were observed, H. darwini preferred cool retreats, whereas H. borelli used the warmer ones. Body size, coloration and geographic distribution may be related to the different patterns observed.

In situ AFM study on barite (0 0 1) surface dissolution in NaCl solutions at 30 °C

International Nuclear Information System (INIS)

Kuwahara, Yoshihiro; Makio, Masato

2014-01-01

Highlights: • We examined barite surface dissolution behavior in NaCl solutions by AFM. • Step retreat and step splitting behavior changed with the NaCl concentration. • Etch pit formation and development differed in each NaCl solution. • Step retreat and etch pit growth rates increased with the NaCl concentration. • We assessed the effects of temperature and NaCl concentration on these rates. - Abstract: This paper reports in situ observations on barite (0 0 1) surface dissolution behavior in 0.1–0.001 M NaCl solutions at 30 °C using atomic force microscopy (AFM). The step retreating on barite (0 0 1) surfaces changed with increasing NaCl solution concentrations. In solutions with a higher NaCl concentration (⩾0.01 M), many steps showed curved or irregular fronts during the later experimental stage, while almost all steps in solutions with a lower NaCl concentration exhibited straight or angular fronts, even during the late stage. The splitting phenomenon of the initial 〈h k 0〉 one-layer steps (7.2 Å) into two half-layer steps (3.6 Å) occurred in all NaCl solutions, while that of the initial [0 1 0] one-layer steps observed only in the 0.1 M NaCl solution. The step retreat rates increased with an increasing NaCl solution concentration. We observed triangular etch pit and deep etch pit formation in all NaCl solutions, which tended to form late in solutions with lower NaCl concentrations. The deep etch pit morphology changed with increasing NaCl solution concentrations. A hexagonal form elongated in the [0 1 0] direction was bounded by the {1 0 0}, {3 1 0}, and (0 0 1) faces in a 0.001 M NaCl solution, and a rhombic form was bounded by the {5 1 0} and (0 0 1) faces in 0.01 M and 0.1 M NaCl solutions. An intermediate form was observed in a 0.005 M NaCl solution, which was defined by {1 0 0}, a curved face tangent to the [0 1 0] direction, {3 1 0}, and (0 0 1) faces: the intermediate form appeared between the hexagonal and rhombic forms in

Evolution and erosion processes in gullies Bardenas Reales (Navarra). Spain

International Nuclear Information System (INIS)

Desir, G.; Marin, C.

2009-01-01

At the Bardenas Reales site, guilles are developed over Halocene silts and show a great extend. the most typical features is the lack of relief and the presence of many low and narrow guilles, on which the sidewalls are affected by piping and incision processes. Gullies have a U-Shape section and a dendritic pattern with a high sinuosity. Guilles evolution responds to different processes like headcut retreat, scouring, undermining and piping. One of these minor order guilles has evolved from a man made ditch builded in 1997. This dicth acts a as grainpipe of the erosion plot BD1. The main processes was headuct retreat from the outlet point in the main gully, and the deepening and widening of the ditch botoom level. As a consequence of undermining and piping the ditch shows an enlargement and headcut retreat yhat evolve in an unusual speed in comparison with the environment, that let us to stablish a temporal sequence of the gully evolution in these areas. (Author) 8 refs.

Deterrence, the spiral model, and intentions of the adversary

International Nuclear Information System (INIS)

Jervis, R.

1986-01-01

This paper is not concerned with the many subtleties and complexities of deterrence theory, but only with the central argument that great dangers arise if an aggressor believes that the status quo powers are weak in capability or resolve. This belief will lead the former to test its opponents, usually starting with a small and apparently unimportant issue. If the status quo powers retreat, they will not only lose the specific value at stake but, more important in the long run, will encourage the aggressor to press harder. Even if the defenders later recognize their plight and are willing to pay a higher price to prevent further retreats, they will find it increasingly difficult to convince the aggressor of their new-found resolve. The choice will then be between continuing to retreat and thereby sacrificing basic values or fighting. To avoid this disastrous situation, the state must display the ability and willingness to wage war. It may not be able to ignore minor conflicts or to judge disputes on their merits. Issues of little intrinsic value become highly significant as indices of resolve

Low post-glacial rebound rates in the Weddell Sea due to Late Holocene ice-sheet readvance

Science.gov (United States)

Bradley, Sarah L.; Hindmarsh, Richard C. A.; Whitehouse, Pippa L.; Bentley, Michael J.; King, Matt A.

2015-03-01

Many ice-sheet reconstructions assume monotonic Holocene retreat for the West Antarctic Ice Sheet, but an increasing number of glaciological observations infer that some portions of the ice sheet may be readvancing, following retreat behind the present-day margin. A readvance in the Weddell Sea region can reconcile two outstanding problems: (i) the present-day widespread occurrence of seemingly stable ice streams grounded on beds that deepen inland; and (ii) the inability of models of glacial isostatic adjustment to match present-day uplift rates. By combining a suite of ice loading histories that include a readvance with a model of glacial isostatic adjustment we report substantial improvements to predictions of present-day uplift rates, including reconciling one problematic observation of land sinking. We suggest retreat behind present grounding lines occurred when the bed was lower, and isostatic recovery has since led to shallowing, ice sheet re-grounding and readvance. The paradoxical existence of grounding lines in apparently unstable configurations on reverse bed slopes may be resolved by invoking the process of unstable advance, in accordance with our load modelling.

Some aspects of the last glaciation in the Mazury Lake District (north-eastern Poland

Directory of Open Access Journals (Sweden)

Pochocka-Szwarc Katarzyna

2013-06-01

Full Text Available The morphology of the Mazury Lake District (north-eastern Poland dates from 24-19 ka (main stadial of the youngest Vistulian glaciation. During this last glacial maximum (MIS 2 a belt with lacustrine basins was formed when the ice sheet retreated at the end of the Pomeranian phase. The ice-sheet retreat is morphologically also expressed by the occurrence of end moraines. The study area is situated in the Skaliska Basin, in the northern part of the Lake District (near the Polish/ Russian border, at the periphery of zone with end moraines. Originally the basin was an ice-dammed depression filled with melt water; the water flowed out into the developing Pregoła valley when the ice retreated and did no longer dam off the depression. The basin, which is surrounded by hill-shaped moraines, is filled now with Late Glacial and Holocene glaciolacustrine sediments. The organic sediments of the basin record the history of the Late Glacial and Holocene climatic changes in this region.

Clinical decision making in restorative dentistry, endodontics, and antibiotic prescription.

Science.gov (United States)

Zadik, Yehuda; Levin, Liran

2008-01-01

The purpose of this study was to evaluate the influence of geographic location of graduation (Israel, Eastern Europe, Latin America) on decision making regarding management of dental caries, periapical lesions, and antibiotic prescribing routines. A questionnaire was given to ninety-eight general practitioners regarding demographic and work habits. Photographs of lesions were shown on a screen. Participants reported recommended treatment and whether they would routinely prescribe antibiotics following regular endodontic treatment, retreatment, and impacted third molar surgical extraction in healthy patients. There was a 94 percent (n=92) response rate, of which eighty-five responses were used in the data analysis. Surgical treatment of asymptomatic enamel caries lesions was not recommended by most of the subjects, and surgery was recommended for DEJ caries lesions in low or moderate caries risk patients, both without significant differences between geographic regions of dental school graduation. Israelis had a lower frequency of retreatment in asymptomatic teeth that demonstrated periapical radiolucency with post restoration (without crown) compared to Latin Americans and East Europeans. Most of the participants would not retreat asymptomatic teeth that demonstrated periapical radiolucency with post and crown. After third molar surgery, 46 percent of participants routinely prescribed antibiotics. Significantly more Latin American graduates prescribed antibiotics following endodontic treatment, retreatment, and third molar extractions (pantibiotics) and overtreatment (caries) among young practitioners reflect failure of undergraduate education in proper use of antibiotics and management of the carious lesions according to the patient's clinical presentation and caries risk assessment rather than routinely undertaking surgical caries treatment.

Lunar recession encoded in tidal rhythmites: a selective overview with examples from Argentina

Science.gov (United States)

de Azarevich, Vanina L. López; Azarevich, Miguel B.

2017-08-01

The study of tides from the sedimentary record of tidal rhythmites, applying fast Fourier transform analysis, contributes to the understanding of the surficial evolution of our highly dynamic planet, and of the astronomical cycles that influenced the ancient tidal systems. This overview of lunar retreat rates, which includes examples from Argentina, displays a generalized pattern of nonlinear, progressively extended lunar cycles up to the present day. The lunar retreat calculated at different stages of the Earth's history identifies three time spans of extremely high recession rates, amounting to almost twice that of the present day: Archean-Paleoproterozoic (6.93 cm/year), Neoproterozoic I-Ediacaran (7.01 cm/year) and Ediacaran-early Cambrian (6.48 cm/year). Older comparable recession rates are difficult to recognize because of the lack of tidal rhythmic sequences. The maximum lunar retreat rate is registered after the Copernican meteor bombardment event on the Moon at 900 Ma, and the time span coincides with the continental dispersal of Rodinia. Every acceleration of the lunar retreat rate coincides with two main processes: (1) meteorite impacts on the Earth or Moon, and (2) reconfiguration of landmasses accompanied by earthquakes that generated changes in the rotational axis of the Earth, inundation surfaces, and glaciation/deglaciation processes. The simultaneous occurrence of such processes makes it difficult to distinguish the causes and effects of each individual process, but its conjunction would have promoted the destabilization of the Earth-Moon system in terms of moment of inertia that was transferred to the Moon rotation.

Antiaging Effects of an Intensive Mind and Body Therapeutic Program through Enhancement of Telomerase Activity and Adult Stem Cell Counts.

Science.gov (United States)

Rao, Krishna S; Chakraharti, Swarup K; Dongare, Vaishali S; Chetana, K; Ramirez, Christina M; Koka, Prasad S; Deb, Kaushik D

2015-01-01

Key modalities of integrative medicine known to rejuvenate the mind and body are meditation, yoga, and controlled diet. It has been shown previously that intensive or prolonged mind and body therapies (MBT) may have beneficial effects on the well-being of healthy people and in patients. Telomerase activity and levels of peripheral blood adult pluripotent stem cells (PB-APSC) are reliable markers of long-term well-being that are known to decrease with age. The objective of this study is to understand the effect of our MBT program on telomerase activity and stem cells in blood collected from the participants. Here, we have investigated the effects of an intensive three weeks MBT retreat on telomerase activity and the peripheral blood stem cells in participants before and after the MBT. A total of 108 people were enrolled in the study; 38 men and 70 women (aged 18-90) randomly assigned for the study. Telomerase activity was greater in retreat participants at the end of the MBT retreat. About 45% of people showed more than one-fold increase of telomerase activity after our MBT program. Furthermore, about 27% of people showed more pronounced fold increase (2-fold) in telomerase activity after the MBT. In addition, a substantial percentage of people (about 90%) exhibited increased stem cell counts after the MBT. The data suggest increased telomerase activity and stem cells count in peripheral blood from MBT retreat participants that may lead to increased longevity and better quality of life at latter age.

Simulating ice thickness and velocity evolution of Upernavik Isstrøm 1849-2012 by forcing prescribed terminus positions in ISSM

Science.gov (United States)

Haubner, Konstanze; Box, Jason E.; Schlegel, Nicole J.; Larour, Eric Y.; Morlighem, Mathieu; Solgaard, Anne M.; Kjeldsen, Kristian K.; Larsen, Signe H.; Rignot, Eric; Dupont, Todd K.; Kjær, Kurt H.

2018-04-01

Tidewater glacier velocity and mass balance are known to be highly responsive to terminus position change. Yet it remains challenging for ice flow models to reproduce observed ice margin changes. Here, using the Ice Sheet System Model (ISSM; Larour et al. 2012), we simulate the ice velocity and thickness changes of Upernavik Isstrøm (north-western Greenland) by prescribing a collection of 27 observed terminus positions spanning 164 years (1849-2012). The simulation shows increased ice velocity during the 1930s, the late 1970s and between 1995 and 2012 when terminus retreat was observed along with negative surface mass balance anomalies. Three distinct mass balance states are evident in the reconstruction: (1849-1932) with near zero mass balance, (1932-1992) with ice mass loss dominated by ice dynamical flow, and (1998-2012), when increased retreat and negative surface mass balance anomalies led to mass loss that was twice that of any earlier period. Over the multi-decadal simulation, mass loss was dominated by thinning and acceleration responsible for 70 % of the total mass loss induced by prescribed change in terminus position. The remaining 30 % of the total ice mass loss resulted directly from prescribed terminus retreat and decreasing surface mass balance. Although the method can not explain the cause of glacier retreat, it enables the reconstruction of ice flow and geometry during 1849-2012. Given annual or seasonal observed terminus front positions, this method could be a useful tool for evaluating simulations investigating the effect of calving laws.

Re-irradiation tolerance in the rat spinal cord

International Nuclear Information System (INIS)

Shun Wong, C.; Poon, J.K.; Hill, R.P.

1993-01-01

The influence of the level of initial radiation damage on the long term recovery and re-irradiation tolerance in the rat spinal cord was investigated. Rats were irradiated with 0, 10, 20, 30 and 36 daily fractions of 2.15 Gy initially representing 0, 25, 50, 75 and 90% of cord tolerance. After an interval of 20 weeks, retreatments were given using graded single doses of X-ray. The end-point was paralysis of the forelimbs due to white matter necrosis. Latent times to paralysis were inversely proportional to the level of initial injury and retreatment doses. The retreatment ED 50 s were 19.0, 17.0, 15.7, 14.0 and 11.8 Gy for the control animals and animals irradiated initially with 10. 20, 30 and 36 fractions of 2.15 Gy respectively. Using the extrapolated response dose (ERD) concept, α/β of 3.0 Gy, the retreatment of ED 50 s in % ERD were 81, 70, 58 and 42% after initial doses of 25, 50, 75 and 90% ERD respectively. The level of initial injury appeared to influence the proportion of residual injury. For an initial injury of 25 and 90% of ERD, the respective residual injury was 74 and 65% of the initial damage; for an initial injury of 50 and 75% ERD, the residual injury decreased to 59 and 57% respectively. It is concluded that there was significant long-term recovery in the rat spinal cord, and that the level of initial radiation damage influenced both the treatment tolerance and the time expression of injury. (author). tabs

Glacial Survival of Boreal Trees in Northern Scandinavia

DEFF Research Database (Denmark)

Parducci, L; Jørgensen, Tina; Tollefsrud, M M

2012-01-01

It is commonly believed that trees were absent in Scandinavia during the last glaciation and first recolonized the Scandinavian Peninsula with the retreat of its ice sheet some 9000 years ago. Here, we show the presence of a rare mitochondrial DNA haplotype of spruce that appears unique to Scandi......It is commonly believed that trees were absent in Scandinavia during the last glaciation and first recolonized the Scandinavian Peninsula with the retreat of its ice sheet some 9000 years ago. Here, we show the presence of a rare mitochondrial DNA haplotype of spruce that appears unique...

High-resolution reconstruction of a coastal barrier system

DEFF Research Database (Denmark)

Fruergaard, Mikkel; Andersen, Thorbjørn Joest; Nielsen, Lars Henrik

2015-01-01

This study presents a detailed reconstruction of the sedimentary effects of Holocene sea-level rise on a modern coastal barrier system (CBS). Increasing concern over the evolution of CBSs due to future accelerated rates of sea-level rise calls for a better understanding of coastal barriers response...... from retreat of the barrier island and probably also due to formation of a tidal inlet close to the study area. Continued transgression and shoreface retreat created a distinct hiatus and wave ravinement surface in the seaward part of the CBS before the barrier shoreline stabilised between 5.0 and 4...

Studies on the effective methods for induction of mutations of vegetatively propagated plants by the use of the gamma field

International Nuclear Information System (INIS)

Nakajima, Kenji

1977-01-01

In the gamma field for the whole plant irradiation of vegetatively propagated plants, artificial induction of mutations in rose, tea, mulberry and chrysanthemum has been studied since 1962. The studies include induction of wholly mutated shoots (sports), irradiation techniques for mutation induction, usage of cultivars in mutation breeding and re-treatment of induced mutations with gamma ray. The results so far attained are described as follows: effects of the cutting back treatment on the induction of sports; induction of radiation injuries and mutations by whole plant irradiation; and re-treatment of induced mutants with gamma ray. (Mori, K.)

Short-Term Bluff Recession Behavior Along Pennsylvania's Great Lakes Coastline, USA

Science.gov (United States)

Foyle, A. M.; Naber, M. D.; Pluta, M. J.

2011-12-01

Coastal bluff retreat is a common problem along the world's unconsolidated coastlines. On the Great Lakes coast of Pennsylvania, Quaternary clay-rich glacial till, paleo-lake plain, and sandy strandplain sequences overlie Devonian bedrock. These Quaternary strata are subject to subaerial and lacustrine erosional processes that cause permanent coastal land loss at spatially variable rates, with the former (runoff, slumping, groundwater focusing, etc) dominating over the latter (wave and current scour, abrasion, etc). Land loss is of concern to environmental agencies because land-use planning should account for spatial and temporal variability in land-loss rates, and because bluff erosion contributes to a temporary degradation in coastal water quality. The goal of this study is to evaluate spatial variability in bluff retreat rates along a 20 km sector of Pennsylvania's short Great Lakes coast. High resolution LiDAR data covering a one-decade time frame (1998-2007) permit bluff-crest mapping on two comparable data sets that captures change within a timeframe similar to CZM planning intervals. Short-term recession data can be more useful, cost-effective, and accurate than long-term analyses that use lower-resolution field measurements, T-sheets, and historical aerial photography. Bluffs along the 20 km coastal study site consist of up to 26 m of unlithified Quaternary sediments overlying a 1-4 m ledge of sub-horizontal Devonian shale and sandstone. Bluff slopes range from 20-90 degrees, beaches are narrow (wide) or absent, and the bluffs are seasonally shielded by ground-freeze and lake ice. DEMs, hillshades, and slope and contour maps were generated from bare-earth 1998 and 2007 LiDAR data, and checked against 2005 aerial ortho-photography. Maps were analyzed at a scale of 1:120 in ArcGIS and the bluff crest was identified primarily by the visual-break-in-slope method. Rates of bluff retreat derived using DSAS vary from unresolvable to as much as 2.2 m/yr, averaging

Water reclamation and effluent retreatment system at Jaduguda

Energy Technology Data Exchange (ETDEWEB)

Beri, K K [Uranium Corporation of India Limited, Jaduguda Mines, Singhbhum (India)

1994-06-01

Neutralization of uranium mill tailing with lime provided in original flow sheet was not found adequate for effluent quality control within limits particularly as regards to{sup 226}Ra and Mn. The same was being controlled by dilution and hence no water was being reclaimed. In October 1987 the Jaduguda mill was expanded to augment its ore processing capacity from 1000 MT/day to 1340 MT/day. This necessitated extra water requirement, which could have been met only with water reclamation. But this would have resulted in build up of pollutant ions apart from less water available for dilution. Hence a composite scheme was made for water reclamation and treatment of effluent with BaCl{sub 2} to precipitate Ba(Ra)So{sub 4} and with lime to precipitate Mn as hydroxide. This effluent treatment plant was commissioned in May 1990 and is working satisfactorily. The scheme is being further modified and augmented to take care of Narwa mine water and sewage treatment plant effluent. (author).

MECHANISM OF GULLY-HEAD RETREAT - A STUDY AT ...

African Journals Online (AJOL)

Osondu

Geotechnical properties of soil like cohesion and angle of internal ... downstream with detrimental effects on water quality .... Three processes of gully head erosion with an aerated ... increasing infiltration into the soil profile. (Bradford, et al,.

[Nonsurgical retreatment of lateral radiopacity after surgical treatment].

Science.gov (United States)

Arias de Luxan, A

1990-01-01

A case report is presented of an upper central incisor with incomplete endodontic procedure evidencing a radiolucent image that was treated by apicoectomy and retroamalgam. A year later the periapical lesion had healed completely but a new lateral radiolucency is observed. A reentry of the canal is performed eliminating the old obturating material, biomechanical preparation and obturation with sealer and thermo gutta-percha. The lesion was cured in nine months.

Education, Labor Markets and the Retreat from Marriage

Science.gov (United States)

Harknett, Kristen; Kuperberg, Arielle

2011-01-01

Using data from the Fragile Families and Child Wellbeing study and the Current Population Survey, we find that labor market conditions play a large role in explaining the positive relationship between educational attainment and marriage. Our results suggest that if low-educated parents enjoyed the same, stronger labor market conditions as their…

Retreatability of Root Canals Obturated using Mineral Trioxide ...

African Journals Online (AJOL)

2018-04-04

Apr 4, 2018 ... 2018 Nigerian Journal of Clinical Practice | Published by Wolters Kluwer ‑ Medknow. Background: ... remaining RCFM was evaluated using digital camera. The images ... trioxide aggregate-based and two resin-based sealers. Niger J Clin ... glass ionomer cement and the specimens were stored at. 37°C in ...

Metodología para elaborar leyes de posibilidad de retirada del cliente: una aplicación al sector del vestido // A Methodology to Elaborate Laws of Possibilities in the Retreat of a Client: An Application to the Dress Sector

Directory of Open Access Journals (Sweden)

Mauricio Ortigosa Hernández

2016-12-01

Full Text Available El presente documento pone a prueba en el sector del vestido en el centro del país, una metodología basada en la teoría de la incertidumbre y los subconjuntos borrosos para construir leyes de posibilidad de retirada del cliente con la empresa, con tan sólo la opinión subjetiva de expertos. La aportación del presente trabajo permite obtener un camino alternativo cuando no es posible contar con la información requerida por los modelos identificados en la literatura basados en principios derivados de las leyes del azar, incluso métodos heurísticos. Los resultados muestran la utilidad de los conceptos borrosos en un problema donde la incertidumbre en relación a la permanencia del cliente se hace evidente, permitiendo obtener un elemento necesario (tiempo, cuando se requiera medir el valor económico del cliente (Customer Lifetime Value: CLV en el campo de la incertidumbre. ------------------------------------ The current work tests, in the dress sector in the center of the country, a methodology based in the theory of uncertainty and the fuzzy subsets, in order to build laws of possibilities for the retreat of clients only with the subjective opinion given by experts. The contribution of the present work allows to obtain an alternative path when it is not possible to get the required information by the models identified in the literature based in principles derived of the random laws even from heuristic methods. The results show the utility of fuzzy concepts in a problem where the uncertainty in relation to the permanence of the client is evident and allows to obtain a valuable element (time, when the Customer Lifetime Value (CLV is required to be measured in the field of uncertainty.

Frequency, triggering factors and possible consequences of mass movements on outlet glaciers in Iceland.

Science.gov (United States)

Saemundsson, Thorsteinn; Margeirsson, Guðbjörn

2016-04-01

During the last 15 years several mass movements of various size and origin, e.g. rock avalanches, rock slides and debris slides have been observed to have fall on outlet glaciers in Iceland. This should not come as a surprise in this type of glacial environment, but in a way it does. When looking at the history only few mass movements are recorded to have fall on outlet glaciers in Iceland, during the decades before the year 2000 or since 1960. This "lack of mass movements" can be explained by the fact that fewer observations and monitoring were done in the past, but is it so or are we seeing increasing activity? Looking at the distribution of the known mass movements, two activity periods cam be identified. The former one around 1970 and the second one starting around 2000 and is still ongoing. Both of these periods are characterized by warmer climate leading to retreating phases of glaciers. Two larger mass movements are known from these two retreating periods. The former one occurred in January 1967. Then a large rockslide fell on the snout and into the glacial lake of the Steinholtsjökull outlet glacier in the northern side of the Eyjafjallajökull ice cap. The rockslide broke up the snout of the glacier and caused large floodwave bursting down the Steinholtsdalur valley transporting large volume of sediments down its path. The later one occurred in 2007, when a large rockavalanche fell on the Morsárjökull outlet glacier, in the southern side of the Vatnajökull ice cap. The avalanche debris covered around 1/5 of the glacier surface. Today the retreat and thinning of glaciers in Iceland are extremely rapid. The consequences of such a rapid retreat are e.g. unstable valley slopes surrounding the outlet glaciers, both in loose sediments and bedrock, thawing of mountain permafrost and not least formation of glacial lakes in front of the rapid retreating ice margins. Such conditions can become extremely hazardous, as seen by the above mentioned examples, both

The Prevalence of Drug-Resistant Tuberculosis in Mainland China: An Updated Systematic Review and Meta-Analysis.

Science.gov (United States)

Duan, Qionghong; Chen, Zi; Chen, Cong; Zhang, Zhengbin; Lu, Zhouqin; Yang, Yalong; Zhang, Lin

2016-01-01

In recent years, drug resistant tuberculosis (DR-TB) particularly the emergence of multi-drug-resistant tuberculosis (MDR-TB) has become a major public health issue. The most recent study regarding the prevalence of drug-resistant tuberculosis in mainland China was a meta-analysis published in 2011, and the subjects from the included studies were mostly enrolled before 2008, thus making it now obsolete. Current data on the national prevalence of DR-TB is needed. This review aims to provide a comprehensive and up-to-date assessment of the status of DR-TB epidemic in mainland China. A systematic review and meta-analysis of studies regarding the prevalence of drug-resistant tuberculosis in mainland China was performed. Pubmed/MEDLINE, EMBASE, the Cochrane central database, the Chinese Biomedical Literature Database and the China National Knowledge Infrastructure Database were searched for studies relevant to drug-resistant tuberculosis that were published between January 1, 2012 and May 18, 2015. Comprehensive Meta-Analysis (V2.2, Biostat) software was used to analyse the data. A total of fifty-nine articles, published from 2012 to 2015, were included in our review. The result of this meta-analysis demonstrated that among new cases, the rate of resistance to any drug was 20.1% (18.0%-22.3%; n/N = 7203/34314) and among retreatment cases, the rate was 49.8% (46.0%-53.6%; n/N = 4155/8291). Multi-drug resistance among new and retreatment cases was 4.8% (4.0%-5.7%; n/N = 2300/42946) and 26.3% (23.1%-29.7%; n/N = 3125/11589) respectively. The results were significantly heterogeneous (pdrug resistance patterns were found by subgroup analysis according to geographic areas, subject enrolment time, and methods of drug susceptibility test (DST). The prevalence of resistance to any drug evidently dropped for both new and retreatment cases, and multi-drug resistance declined among new cases but became more prevalent among retreatment cases compared to the data before 2008

Landslides and rock fall processes in the proglacial area of the Gepatsch glacier, Tyrol, Austria - Quantitative assessment of controlling factors and process rates

Science.gov (United States)

Vehling, Lucas; Rohn, Joachim; Moser, Michael

2013-04-01

Due to the rapid deglaciation since 1850, lithological structures and topoclimatic factors, mass movements like rock fall, landslides and complex processes are important contributing factors to sediment transport and modification of the earth's surface in the steep, high mountain catchment of the Gepatsch reservoir. Contemporary geotechnical processes, mass movement deposits, their source areas, and controlling factors like material properties and relief parameters are mapped in the field, on Orthofotos and on digital elevation models. The results are presented in an Arc-Gis based geotechnical map. All mapped mass movements are stored in an Arc-Gis geodatabase and can be queried regarding properties, volume and controlling factors, so that statistical analyses can be conducted. The assessment of rock wall retreat rates is carried out by three different methods in multiple locations, which differ in altitude, exposition, lithology and deglaciation time: Firstly, rock fall processes and rates are investigated in detail on five rock fall collector nets with an overall size of 750 m2. Rock fall particles are gathered, weighed and grain size distribution is detected by sieving and measuring the diameter of the particles to distinct between rock fall processes and magnitudes. Rock wall erosion processes like joint formation and expansions are measured with high temporal resolution by electrical crack meters, together with rock- and air temperature. Secondly, in cooperation with the other working groups in the PROSA project, rock fall volumes are determined with multitemporal terrestrial laserscanning from several locations. Lately, already triggered rock falls are accounted by mapping the volume of the deposit and calculating of the bedrock source area. The deposition time span is fixed by consideration of the late Holocene lateral moraines and analysing historical aerial photographs, so that longer term rock wall retreat rates can be calculated. In order to limit

Repeat Gamma Knife surgery for vestibular schwannomas

Science.gov (United States)

Lonneville, Sarah; Delbrouck, Carine; Renier, Cécile; Devriendt, Daniel; Massager, Nicolas

2015-01-01

Background: Gamma Knife (GK) surgery is a recognized treatment option for the management of small to medium-sized vestibular schwannoma (VS) associated with high-tumor control and low morbidity. When a radiosurgical treatment fails to stop tumor growth, repeat GK surgery can be proposed in selected cases. Methods: A series of 27 GK retreatments was performed in 25 patients with VS; 2 patients underwent three procedures. The median time interval between GK treatments was 45 months. The median margin dose used for the first, second, and third GK treatments was 12 Gy, 12 Gy, and 14 Gy, respectively. Six patients (4 patients for the second irradiation and 2 patients for the third irradiation) with partial tumor regrowth were treated only on the growing part of the tumor using a median margin dose of 13 Gy. The median tumor volume was 0.9, 2.3, and 0.7 cc for the first, second, and third treatments, respectively. Stereotactic positron emission tomography (PET) guidance was used for dose planning in 6 cases. Results: Mean follow-up duration was 46 months (range 24–110). At the last follow-up, 85% of schwannomas were controlled. The tumor volume decreased, remained unchanged, or increased after retreatment in 15, 8, and 4 cases, respectively. Four patients had PET during follow-up, and all showed a significant metabolic decrease of the tumor. Hearing was not preserved after retreatment in any patients. New facial or trigeminal palsy did not occur after retreatment. Conclusions: Our results support the long-term efficacy and low morbidity of repeat GK treatment for selected patients with tumor growth after initial treatment. PMID:26500799

End of the Little Ice Age in the Alps forced by industrial black carbon.

Science.gov (United States)

Painter, Thomas H; Flanner, Mark G; Kaser, Georg; Marzeion, Ben; VanCuren, Richard A; Abdalati, Waleed

2013-09-17

Glaciers in the European Alps began to retreat abruptly from their mid-19th century maximum, marking what appeared to be the end of the Little Ice Age. Alpine temperature and precipitation records suggest that glaciers should instead have continued to grow until circa 1910. Radiative forcing by increasing deposition of industrial black carbon to snow may represent the driver of the abrupt glacier retreats in the Alps that began in the mid-19th century. Ice cores indicate that black carbon concentrations increased abruptly in the mid-19th century and largely continued to increase into the 20th century, consistent with known increases in black carbon emissions from the industrialization of Western Europe. Inferred annual surface radiative forcings increased stepwise to 13-17 W⋅m(-2) between 1850 and 1880, and to 9-22 W⋅m(-2) in the early 1900s, with snowmelt season (April/May/June) forcings reaching greater than 35 W⋅m(-2) by the early 1900s. These snowmelt season radiative forcings would have resulted in additional annual snow melting of as much as 0.9 m water equivalent across the melt season. Simulations of glacier mass balances with radiative forcing-equivalent changes in atmospheric temperatures result in conservative estimates of accumulating negative mass balances of magnitude -15 m water equivalent by 1900 and -30 m water equivalent by 1930, magnitudes and timing consistent with the observed retreat. These results suggest a possible physical explanation for the abrupt retreat of glaciers in the Alps in the mid-19th century that is consistent with existing temperature and precipitation records and reconstructions.

CIRCLE Enhancement After Myopic SMILE.

Science.gov (United States)

Siedlecki, Jakob; Luft, Nikolaus; Mayer, Wolfgang J; Siedlecki, Martin; Kook, Daniel; Meyer, Bertram; Bechmann, Martin; Wiltfang, Rainer; Priglinger, Siegfried G; Dirisamer, Martin

2018-05-01

To report the outcomes of enhancement after small incision lenticule extraction (SMILE) using the VisuMax CIRCLE option (Carl Zeiss Meditec AG, Jena, Germany), which converts the SMILE cap into a femtosecond LASIK flap for secondary excimer laser application. Of 2,065 SMILE procedures, 22 eyes (1.1%) re-treated with CIRCLE with a follow-up of 3 months were included in the analysis. SMILE was performed in the usual manner. For re-treatment, the CIRCLE procedure was performed with pattern D flap creation on the VisuMax system and subsequent excimer laser ablation with a Zeiss MEL 90 laser (Carl Zeiss Meditec) with plano target in all cases. Spherical equivalent was -5.56 ± 2.22 diopters (D) before SMILE and -0.51 ± 1.08 D before CIRCLE. CIRCLE enhancement was performed after a mean of 10.0 ± 7.9 months, allowed for safe flap lifting in all eyes, and resulted in a final manifest refraction spherical equivalent of 0.18 ± 0.31 D at 3 months (P line of UDVA. Corrected distance visual acuity (CDVA) remained unchanged at all time points (before vs after CIRCLE, P = .40). Two eyes (9.1 %) lost one line of CDVA; no eye lost two or more lines. The safety and efficacy indices were 1.03 and 0.97 at 3 months. The CIRCLE procedure represents an effective re-treatment option after SMILE. Compared to surface ablation re-treatment after SMILE, CIRCLE seems to offer advantages in respect to speed of visual recovery, safety, and predictability, but at the price of flap creation. [J Refract Surg. 2018;34(5):304-309.]. Copyright 2018, SLACK Incorporated.

Disintegration of a marine-based ice stream - evidence from the Norwegian Channel, north-eastern North Sea

Science.gov (United States)

Morén, Björn M.; Petter Sejrup, Hans; Hjelstuen, Berit O.; Haflidason, Haflidi; Schäuble, Cathrina; Borge, Marianne

2014-05-01

The Norwegian Channel Ice Stream repeatedly drained large part of the Fennoscandian Ice Sheet through Mid and Late Pleistocene glacial stages. During parts of Marine Isotope Stages 2 and 3, glacial ice from Fennoscandia and the British Isles coalesced in the central North Sea and the Norwegian Channel Ice Stream reached the shelf edge on multiple occasions. Through the last decades a large amount of acoustic and sediment core data have been collected from the Norwegian Channel, providing a good background for studies focussing on stability- and development-controlling parameters for marine-based ice streams, the retreat rate of the Norwegian Channel Ice Stream, and the behaviour of the Fennoscandian Ice Sheet. Further, this improved understanding can be used to develop more accurate numerical climate models and models which can be used to model ice-sheet behaviour of the past as well as the future. This study presents new acoustic records and data from sediment cores which contribute to a better understanding of the retreat pattern and the retreat rate of the last ice stream that occupied the Norwegian Channel. From bathymetric and TOPAS seismic data, mega-scale glacial lineations, grounding-zone wedges, and end moraines have been mapped, thereby allowing us to reconstruct the pro- and subglacial conditions at the time of the creation of these landforms. It is concluded that the whole Norwegian Channel was deglaciated in just over 1 000 years and that for most of this time the ice margin was located at positions reflected by depositional grounding-zone wedges. Further work will explore the influence of channel shape and feeding of ice from western Norwegian fjords on this retreat pattern through numerical modelling.

The Relative Frequency of Persistent Hyperthyroidism After I131Therapy

International Nuclear Information System (INIS)

Al-EID, M.A.

1998-01-01

517 patients with different types of hyperthyroidism who had treated by I 131 therapy were studied. The study demonstrated that diffuse toxic goiter was the most common type of hyperthyroidism. The relative frequency of persistent hyperthyroidism in all types after the first dose of I 131 utilizing our empirical regimen in estimation of therapy doses was low (9.5%). While high frequency of persistent hyperthyroidism among diffuse toxic goiter patients (14%), probably was due to many factors discussed in this paper. Some of these factors are impossible to be estimated precisely and therefore, can not be avoided. But careful dose estimation for each case with diffuse toxic goiter may reduce the rate of retreatment by I 131 . Antithyroid medication prior to I 131 therapy might be another factor resulted in increasing of retreatment of retreatment rate diffuse toxic goiter cases. Longer time interval (more than 5 days) of ceasing antithyroid medication prior therapy is suggested to avoid the effects of these drugs. Patients with other types of hyperthyroidism were not frequently required more than one dose and the frequency of persistent hyperthyroidism was almost negligible

Gambling accessibility: a scale to measure gambler preferences.

Science.gov (United States)

Moore, Susan M; Thomas, Anna C; Kyrios, Michael; Bates, Glen; Meredyth, Denise

2011-03-01

Geographic closeness of gambling venues is not the only aspect of accessibility likely to affect gambling frequency. Perceived accessibility of gambling venues may include other features such as convenience (e.g., opening hours) or "atmosphere". The aim of the current study was to develop a multidimensional measure of gamblers' perceptions of accessibility, and present evidence for its reliability and validity. We surveyed 303 gamblers with 43 items developed to measure different dimensions of accessibility. Factor analysis of the items produced a two factor solution. The first, Social Accessibility related to the level at which gambling venues were enjoyed because they were social places, provided varying entertainment options and had a pleasant atmosphere. The second factor, Accessible Retreat related to the degree to which venues were enjoyed because they were geographically and temporally available and provided a familiar and anonymous retreat with few interruptions or distractions. Both factors, developed as reliable subscales of the new Gambling Access Scale, demonstrated construct validity through their correlations with other gambling-related measures. Social Accessibility was moderately related to gambling frequency and amount spent, but not to problem gambling, while, as hypothesised, Accessible Retreat was associated with stronger urges to gamble and gambling problems.

On the interannual variability of the Bonin high associated with the East Asian summer monsoon rain

Energy Technology Data Exchange (ETDEWEB)

Ha, Kyung-Ja; Lee, Sun-Seon [Pusan National University, Department of Atmospheric Sciences, Busan (Korea)

2007-01-15

In order to assess how the Bonin high affects interannual variability of the East Asian summer monsoon (EASM) around the Korean Peninsula, the pulsation of the Bonin high and its association with teleconnection patterns was examined. The major factor for the interannual intensity of the EASM is the center position of the Bonin high rather than its center pressure. Up to 12 harmonics over time can be used to reconstruct the Bonin high, demonstrating its intraseasonal variation. The interannual variability of the Bonin high correlates with the Tibet high. This correlation is dominant for the EASM onset time, though not its retreat. The primary teleconnection pattern, reliant up on the interannual variability of the Bonin high, is the Western Pacific oscillation (WPO) in April. In relation to long-term variability, the correlation between the WPO and the Bonin high appears to contribute to the retreat stage of the EASM, which has itself increased since the mid-1970s. Furthermore, the WPO in May and the Tibet correlation has marked the onset rather than the retreat of the EASM since the 1970s. This highly correlated pattern since the mid-1970s may be the result of El Nino. (orig.)

Sediment transport drives tidewater glacier periodicity.

Science.gov (United States)

Brinkerhoff, Douglas; Truffer, Martin; Aschwanden, Andy

2017-07-21

Most of Earth's glaciers are retreating, but some tidewater glaciers are advancing despite increasing temperatures and contrary to their neighbors. This can be explained by the coupling of ice and sediment dynamics: a shoal forms at the glacier terminus, reducing ice discharge and causing advance towards an unstable configuration followed by abrupt retreat, in a process known as the tidewater glacier cycle. Here we use a numerical model calibrated with observations to show that interactions between ice flow, glacial erosion, and sediment transport drive these cycles, which occur independent of climate variations. Water availability controls cycle period and amplitude, and enhanced melt from future warming could trigger advance even in glaciers that are steady or retreating, complicating interpretations of glacier response to climate change. The resulting shifts in sediment and meltwater delivery from changes in glacier configuration may impact interpretations of marine sediments, fjord geochemistry, and marine ecosystems.The reason some of the Earth's tidewater glaciers are advancing despite increasing temperatures is not entirely clear. Here, using a numerical model that simulates both ice and sediment dynamics, the authors show that internal dynamics drive glacier variability independent of climate.

Erosion of Earthen Levees by Wave Action

Science.gov (United States)

Ozeren, Y.; Wren, D. G.; Reba, M. L.

2016-02-01

Earthen levees of aquaculture and irrigation reservoirs in the United States often experience significant erosion due to wind-generated waves. Typically constructed using local soils, unprotected levees are subjected to rapid erosion and retreat due to wind generated waves and surface runoff. Only a limited amount of published work addresses the erosion rates for unprotected levees, and producers who rely on irrigation reservoirs need an economic basis for selecting a protection method for vulnerable levees. This, in turn, means that a relationship between wave energy and erosion of cohesive soils is needed. In this study, laboratory experiments were carried out in order to quantify wave induced levee erosion and retreat. A model erodible bank was packed using a soil consisting of approximately 14% sand, 73% silt, and 13% clay in a 20.6 m long 0.7 m wide and 1.2 m deep wave tank at the USDA-ARS, National Sedimentation Laboratory in Oxford MS. The geometry of the levee face was monitored by digital camera and the waves were measured by means of 6 capacitance wave staffs. Relationships were established between levee erosion, edge and retreat rates, and incident wave energy.

Foot loading characteristics during three fencing-specific movements.

Science.gov (United States)

Trautmann, Caroline; Martinelli, Nicolo; Rosenbaum, Dieter

2011-12-01

Plantar pressure characteristics during fencing movements may provide more specific information about the influence of foot loading on overload injury patterns. Twenty-nine experienced fencers participated in the study. Three fencing-specific movements (lunge, advance, retreat) and normal running were performed with three different shoe models: Ballestra (Nike, USA), Adistar Fencing Lo (Adidas, Germany), and the fencers' own shoes. The Pedar system (Novel, Munich, Germany) was used to collect plantar pressures at 50 Hz. Peak pressures, force-time integrals and contact times for five foot regions were compared between four athletic tasks in the lunge leg and supporting leg. Plantar pressure analysis revealed characteristic pressure distribution patterns for the fencing movements. For the lunge leg, during the lunge and advance movements the heel is predominantly loaded; during retreat, it is the hallux. For the supporting leg, during the lunge and advance movements the forefoot is predominantly loaded; during retreat, it is the hallux. Fencing-specific movements load the plantar surface in a distinct way compared with running. An effective cushioning in the heel and hallux region would help to minimize foot loading during fencing-specific movements.

X-ray diffraction study of reversible deformation mechanisms in the aged uranium-6.5 niobium alloy

International Nuclear Information System (INIS)

Carpenter, D.A.

1985-01-01

The x-ray diffraction (XRD) data from 200 0 C/2h-aged uranium-6.5 wt % niobium (U-6.5Nb) alloys, taken under stress as a function of strain, revealed a gamma-zero (γ 0 )→ alpha prime-prime (α'') thermoelastic martensitic phase transformation. It was concluded that the primary reversible deformation modes consisted of the movement of γ 0 /α'' interphase interfaces and α'' intervariant interfaces. Specimen elasticity at low strains was associated with the retreat of interphase interfaces. At higher strains, interphase interfaces did not recover significantly on unloading, and elasticity was due primarily to the retreat of α'' intervariant interfaces

Neoglacial fluctuations of terrestrial, tidewater, and calving lacustrine glaciers, Blackstone-Spencer Ice Complex, Kenai Mountains, Alaska

Science.gov (United States)

Crossen, Kristine June

1997-12-01

The glaciers surrounding the Blackstone-Spencer Ice Complex display a variety of termini types: Tebenkov, Spencer, Bartlett, Skookum, Trail, Burns, Shakespeare, Marquette, Lawrence, and Ripon glaciers end in terrestrial margins; Blackstone and Beloit glaciers have tidewater termini; and Portage Glacier has a calving lacustrine margin. In addition, steep temperature and precipitation gradients exist across the ice complex from the maritime environment of Prince William Sound to the colder, drier interior. The Neoglacial history of Tebenkov Glacier, as based on overrun trees near the terminus, shows advances ca. 250- 430 AD (calibrated date), ca. 1215-1275 AD (calibrated date), and ca. 1320-1430 AD (tree ring evidence), all intervals of glacier advance around the Gulf of Alaska. However, two tidewater glaciers in Blackstone Bay retreated from their outermost moraines by 1350 AD, apparently asynchronously with respect to the regional climate signal. The most extensive Kenai Mountain glacier expansions during Neoglaciation occurred in the late Little Ice Age. The outermost moraines are adjacent to mature forest stands and bog peats that yield dates as old as 5,600 BP. Prince William Sound glaciers advanced during two Little Ice Age cold periods, 1380-1680 and 1830-1900 AD. The terrestrial glaciers around the Blackstone-Spencer Ice Complex all built moraines during the 19th century and began retreating between 1875 and 1900 AD. Portage and Burns glaciers began retreating between 1790 and 1810 AD, but their margins remained close to the outermost moraines during the 19th century. Regional glacier fluctuations are broadly synchronous in the Gulf of Alaska region. With the exception of the two tidewater glaciers in Blackstone Bay, all glaciers in the Kenai Mountains, no matter their sizes, altitudes, orientations, or types of margins, retreated at the end of the Little Ice Age. The climate signal, especially temperature, appears to be the strongest control on glacier

Final deglaciation of the Scandinavian Ice Sheet and implications for the Holocene global sea-level budget

Science.gov (United States)

Cuzzone, Joshua K.; Clark, Peter U.; Carlson, Anders E.; Ullman, David J.; Rinterknecht, Vincent R.; Milne, Glenn A.; Lunkka, Juha-Pekka; Wohlfarth, Barbara; Marcott, Shaun A.; Caffee, Marc

2016-08-01

The last deglaciation of the Scandinavian Ice Sheet (SIS) from ∼ 21, 000 to 13,000 yr ago is well-constrained by several hundred 10Be and 14C ages. The subsequent retreat history, however, is established primarily from minimum-limiting 14C ages and incomplete Baltic-Sea varve records, leaving a substantial fraction of final SIS retreat history poorly constrained. Here we develop a high-resolution chronology for the final deglaciation of the SIS based on 79 10Be cosmogenic exposure dates sampled along three transects spanning southern to northern Sweden and Finland. Combining this new chronology with existing 10Be ages on deglaciation since the Last Glacial Maximum shows that rates of SIS margin retreat were strongly influenced by deglacial millennial-scale climate variability and its effect on surface mass balance, with regional modulation of retreat associated with dynamical controls. Ice-volume estimates constrained by our new chronology suggest that the SIS contributed ∼ 8 m sea-level equivalent to global sea-level rise between ∼14.5 ka and 10 ka. Final deglaciation was largely complete by ∼10.5 ka, with highest rates of sea-level rise occurring during the Bølling-Allerød, a 50% decrease during the Younger Dryas, and a rapid increase during the early Holocene. Combining our SIS volume estimates with estimated contributions from other remaining Northern Hemisphere ice sheets suggests that the Antarctic Ice Sheet (AIS) contributed 14.4 ± 5.9 m to global sea-level rise since ∼13 ka. This new constraint supports those studies that indicate that an ice volume of 15 m or more of equivalent sea-level rise was lost from the AIS during the last deglaciation.

Reirradiation of Head and Neck Cancers With Intensity Modulated Radiation Therapy: Outcomes and Analyses

Energy Technology Data Exchange (ETDEWEB)

Takiar, Vinita [Department of Radiation Oncology, University of Cincinnati, Cincinnati, Ohio (United States); Garden, Adam S.; Ma, Dominic; Morrison, William H.; Edson, Mark [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Zafereo, Mark E. [Department of Surgical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Gunn, Gary B.; Fuller, Clifton D.; Beadle, Beth; Frank, Steven J. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); William, William N.; Kies, Merrill [Department of Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); El-Naggar, Adel K. [Department of Pathology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Weber, Randal [Department of Surgical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Rosenthal, David I. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Phan, Jack, E-mail: jphan@mdanderson.org [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

2016-07-15

Purpose: To review our 15-year institutional experience using intensity modulated radiation therapy (IMRT) to reirradiate patients with head and neck squamous cell carcinomas (HNSCC) and identify predictors of outcomes and toxicity. Methods and Materials: We retrospectively reviewed the records of 227 patients who received head and neck reirradiation using IMRT from 1999 to 2014. Patients treated with noncurative intent were excluded. Radiation-related acute and late toxicities were recorded. Prognostic variables included performance status, disease site, disease-free interval, chemotherapy, and RT dose and volume. Correlative analyses were performed separately for surgery and nonsurgery patients. Results: Two hundred six patients (91%) were retreated with curative intent, and 173 had HNSCC histology; 104 (50%) underwent salvage resection, and 135 (66%) received chemotherapy. Median follow-up after reirradiation was 24.7 months. Clinical outcomes were worse for HNSCC patients, with 5-year locoregional control, progression-free survival, and overall survival rates of 53%, 22%, and 32%, respectively, compared with 74%, 59%, and 79%, respectively, for non-HNSCC patients. On multivariate analysis, concurrent chemotherapy and retreatment site were associated with tumor control, whereas performance status was associated with survival. Favorable prognostic factors specific to surgery patients were neck retreatment and lack of extracapsular extension, whereas for nonsurgery patients, these were a nasopharynx subsite and complete response to induction chemotherapy. Actuarial rates of grade ≥3 toxicity were 32% at 2 years and 48% at 5 years, with dysphagia or odynophagia being most common. Increased grade ≥3 toxicity was associated with retreatment volume >50 cm{sup 3} and concurrent chemotherapy. Conclusions: Reirradiation with IMRT either definitively or after salvage surgery can produce promising local control and survival in selected patients with head and neck

Reconstructing surface elevation changes for the Greenland Ice Sheet (1993-2013) and analysis of Zachariae Isstrom, northeast Greenland

Science.gov (United States)

Duncan, Kyle

Previous studies investigating the velocity and elevation change records of the Greenland Ice Sheet (GrIS) revealed rapid and complex changes. It is therefore imperative to determine changes with both high spatial and temporal resolutions. By fusing multiple laser altimetry data sets, the Surface Elevation Reconstruction and Change (SERAC) program is capable of reconstructing surface elevation changes with high spatial and temporal resolution over the entire GrIS. The input data include observations from NASA's Ice, Cloud and land Elevation Satellite (ICESat) mission (2003-2009) as well as data collected by NASA's Airborne Topographic Mapper (ATM) (1993-2013) and Land, Vegetation and Ice Sensor (LVIS) (2007-2012) airborne laser altimetry systems. This study extends the record of surface elevation changes over the GrIS by adding 2012 and 2013 laser altimetry data to the previous 1993-2011 record. Extending the record leads to a new, more accurate and detailed altimetry record for 1993-2013. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Digital Elevation Models (DEMs) are fused with laser altimetry data over Zachariae Isstrom, northeast Greenland to analyze surface elevation changes and associated thinning rates during 1978-2014. Little to no elevation change occurred over Zachariae Isstrom from 1978-1999, however, from 1999-2014 elevation changes near the calving front became increasingly negative and accelerated. Calving front position showed steady retreat and grounding line position has been retreating towards the interior of the ice sheet at an increasing rate from 2010-2014 when compared to the 1996-2010 period. The measured elevation changes near the calving front have brought a large portion of the glacier close to the height of flotation. If the current thinning trend continues this portion of the glacier will reach flotation within the next 2-5 years allowing for further retreat and increased vulnerability to retreat for sections of

Factors influencing bank geomorphology and erosion of the Haw River, a high order river in North Carolina, since European settlement.

Science.gov (United States)

Macfall, Janet; Robinette, Paul; Welch, David

2014-01-01

The Haw River, a high order river in the southeastern United States, is characterized by severe bank erosion and geomorphic change from historical conditions of clear waters and connected floodplains. In 2014 it was named one of the 10 most threatened rivers in the United States by American Rivers. Like many developed areas, the region has a history of disturbance including extensive upland soil loss from agriculture, dams, and upstream urbanization. The primary objective of this study was to identify the mechanisms controlling channel form and erosion of the Haw River. Field measurements including bank height, bankfull height, bank angle, root depth and density, riparian land cover and slope, surface protection, river width, and bank retreat were collected at 87 sites along 43.5 km of river. A Bank Erosion Hazard Index (BEHI) was calculated for each study site. Mean bank height was 11.8 m, mean width was 84.3 m, and bank retreat for 2005/2007-2011/2013 was 2.3 m. The greatest bank heights, BEHI values, and bank retreat were adjacent to riparian areas with low slope (<2). This is in contrast to previous studies which identify high slope as a risk factor for erosion. Most of the soils in low slope riparian areas were alluvial, suggesting sediment deposition from upland row crop agriculture and/or flooding. Bank retreat was not correlated to bank heights or BEHI values. Historical dams (1.2-3 m height) were not a significant factor. Erosion of the Haw River in the study section of the river (25% of the river length) contributed 205,320 m3 of sediment and 3759 kg of P annually. Concentration of suspended solids in the river increased with discharge. In conclusion, the Haw River is an unstable system, with river bank erosion and geomodification potential influenced by riparian slope and varied flows.

Evaluating Potential Tipping Points of Antarctic basins

Science.gov (United States)

Durand, G.; Sainan, S.; Pattyn, F.; Jourdain, N.

2017-12-01

Antarctica is currently loosing mass and its forthcoming contribution to sea-level rise could substantially increase during the coming centuries. This is essentially due to geometrical constraints, i.e., in regions where grounded ice lies on a bedrock below sea-level sloping down towards the interior of the ice sheet (retrograde slope). For such a configuration the ice sheet is considered potentially unstable, as suggested by theory. However, recent observations on accelerated grounding-line retreat and new insights in modeling Pine Island and Thwaites glaciers give evidence that such self-sustained retreat, called marine ice sheet instability (MISI), has already been on its way. Although West Antarctica appears to be the most vulnerable region for MISI occurrence, similar topographic configurations are also observed in East Antarctica, in the Wilkes Basin in particular. Therefore, evaluating the MISI potential at a pan-Antarctic scale is becoming a priority. Here, using the f.ETISh ice sheet model, an ensemble of simulations of the entire contemporary Antarctic ice sheet has been carried out. In particular, we investigate the debuttressing of ice shelves required to initiate MISI for each coastal region around Antarctica by forcing the model with realistic sub-shelf melt pulses of varying duration and amplitude. We further identify the currently grounded areas where the outlet glaciers could hardly stabilize, the Amundsen Sea Sector being the more prone to large self-sustained retreats. On the contrary, the ability of Cook and Ninnis ice shelves to recover after large perturbations and enough buttress upstream outlet glaciers tends to limit self-sustained retreat of the sector. For each basin, rates of contribution to sea-level rise are discussed together with the RCPs and time when tipping points could be reached and MISI triggered.

Confluent diode laser coagulation: the gold standard of therapy for retinopathy of prematurity.

Science.gov (United States)

Prepiaková, Zuzana; Tomcíková, Dana; Kostolná, Barbora; Gerinec, Anton

2015-01-01

The authors compare results of retinopathy of prematurity treatment with single-spot diode laser coagulation (DLC) versus confluent DLC. The final anatomical outcome and need for additional therapy, such as additional DLC, cryotherapy, scleral buckling, and intravitreal bevacizumab, were evaluated. A retrospective review of patients with threshold retinopathy of prematurity treated between January 2001 and October 2012 was conducted. Single-spot laser treatment or confluent laser treatment was applied anterior to the ridge extending to the ora serrata. In the first group (the single-spot group), a single-spot DLC was used between January 2001 and May 2008. The single-spot group included 338 patients (671 eyes) with retinopathy of prematurity. In the second group (the confluent group), confluent DLC was used in 326 patients (652 eyes) between June 2008 and October 2012. The authors compared the need for re-treatment to achieve regression of retinopathy of prematurity in both groups. The rate of progression, frequency of re-treatment, complications, and structural outcomes were evaluated. In the single-spot group, re-treatment only with DLC was necessary in 43 (6.4%) eyes, additional cryotherapy was performed in 22 (3.3%) eyes, and scleral buckling in 107 (15.9%) eyes. Altogether, additional therapy was used in 172 (25.6%) eyes. In the confluent group, re-treatment with DLC was used in 5 (0.8%) eyes, additional cryotherapy in 6 (0.9%) eyes, scleral buckling in 16 (2.5%) eyes, and intravitreal bevacizumab in 14 (2.1%) eyes. Altogether, additional therapy was used in 41 (6.3%) eyes. The confluent group showed a favorable anatomical outcome in 99.1% of the cases compared with 96.4% in the single-spot group. The results were statistically significant (P = .001.) The DLC method was significantly more effective than single-spot DLC in the treatment of retinopathy of prematurity. Copyright 2015, SLACK Incorporated.

Changes in flow of Crosson and Dotson ice shelves, West Antarctica, in response to elevated melt

Science.gov (United States)

Lilien, David A.; Joughin, Ian; Smith, Benjamin; Shean, David E.

2018-04-01

Crosson and Dotson ice shelves are two of the most rapidly changing outlets in West Antarctica, displaying both significant thinning and grounding-line retreat in recent decades. We used remotely sensed measurements of velocity and ice geometry to investigate the processes controlling their changes in speed and grounding-line position over the past 20 years. We combined these observations with inverse modeling of the viscosity of the ice shelves to understand how weakening of the shelves affected this speedup. These ice shelves have lost mass continuously since the 1990s, and we find that this loss results from increasing melt beneath both shelves and the increasing speed of Crosson. High melt rates persisted over the period covered by our observations (1996-2014), with the highest rates beneath areas that ungrounded during this time. Grounding-line flux exceeded basin-wide accumulation by about a factor of 2 throughout the study period, consistent with earlier studies, resulting in significant loss of grounded as well as floating ice. The near doubling of Crosson's speed in some areas during this time is likely the result of weakening of its margins and retreat of its grounding line. This speedup contrasts with Dotson, which has maintained its speed despite increasingly high melt rates near its grounding line, likely a result of the sustained competency of the shelf. Our results indicate that changes to melt rates began before 1996 and suggest that observed increases in melt in the 2000s compounded an ongoing retreat of this system. Advection of a channel along Dotson, as well as the grounding-line position of Kohler Glacier, suggests that Dotson experienced a change in flow around the 1970s, which may be the initial cause of its continuing retreat.

Long lasting second remission and quality of life following brachytherapy of relapsing cancer in preirradiated regions. Experience in 108 patients

International Nuclear Information System (INIS)

Schmidt, B.F.; Kwiatkowski, J.

1996-01-01

Introduction: In patients with unresectable relapsing malignant tumor following external beam radiotherapy retreatment by brachytherapy gives a second chance of good palliation and even cure. But regardless the great number of tumor relapse reirradiation is given only to few patients due to the impending risks of severe radiation sequelae. Material and method: From January 1st 1992 to December 31st 1995 overall 108 patients with histologically proven local tumor relapses in preirradiated regions were reirradiated by interstitial or intraluminal brachytherapy (192-Iridium sources). The preirradiation dose was 40 to 70 Gray (Gy) in conventional fractionation. The brachytherapy retreatment dose was 30 to 40 Gy at the individually shaped reference isodose shell. In high dose-rate technique (about two third of all patients) mostly single doses of 5 Gy were applied once or twice a week. If low dose-rate techniques were used, a maximum dose of 60 Gy was applied. In some cases a second course of external beam radiotherapy was added. The sites of reirradiation were: ear-nose-throat-yaw areas 76, large airways 24, soft tissues 7, scalp 1. Results: In (23(108)) patients (21 %) complete or partial remission could be achieved lasting at least one year. In (8(23)) patients (overall 7,4 %) the second remission lasted longer than two years. The quality of life in the long time survivors was felt to be good or at least acceptable. Local necroses, not life threatening, occurred in about 20 %. No fatal complication was to be observed. Altogether in about 85 % the reirradiation resulted in effective palliation and was well tolerated. Discussion and conclusion: Retreatment by brachytherapy yields valuable palliation to the vast majority of patients and gives a second chance of long time good quality survival to about 10 % of all retreated patients. Careful selection of patients and experienced realisation of brachytherapy is essential to avoid severe complications

Intensive meditation for refractory pain and symptoms.

Science.gov (United States)

Goyal, Madhav; Haythornthwaite, Jennifer; Levine, David; Becker, Diane; Vaidya, Dhananjay; Hill-Briggs, Felicia; Ford, Daniel

2010-06-01

The objective of this study was to assess patient interest in intensive meditation training for chronic symptoms. This was a cross-sectional anonymous survey among six chronic disease clinics in Baltimore including Chronic Kidney Disease, Crohn's Disease, Headache, Renal Transplant Recipients, General Rheumatology, and lupus clinic. Subjects were 1119 consecutive patients registering for their appointments at these clinics. Outcome measures were 6-month pain, global symptomatology, four-item perceived stress scale, use of complementary and alternative medicine (CAM) therapies, and attitudes toward use of meditation for managing symptoms. We then gave a scripted description of an intensive, 10-day meditation training retreat. Patient interest in attending such a retreat was assessed. Seventy-seven percent (77%) of patients approached completed the survey. Fifty-three percent (53%) of patients reported moderate to severe pain over the past 6 months. Eighty percent (80%) reported use of some CAM therapy in the past. Thirty-five percent (35%) thought that learning meditation would improve their health, and 49% thought it would reduce stress. Overall, 39% reported interest in attending the intensive 10-day meditation retreat. Among those reporting moderate to severe pain or stress, the percentages were higher (48% and 59%). In a univariate analysis, higher education, nonworking/disabled status, female gender, higher stress, higher pain, higher symptomatology, and any CAM use were all associated with a greater odds of being moderately to very interested in an intensive 10-day meditation retreat. A multivariate model that included prior use of CAM therapies as predictors of interest in the program fit the data significantly better than a model not including CAM therapies (p = 0.0013). Over 50% of patients followed in chronic disease clinics complain of moderate to severe pain. Patients with persistent pain or stress are more likely to be interested in intensive meditation.

Rapid thinning and collapse of lake calving Yakutat Glacier, Southeast Alaska

Science.gov (United States)

Trussel, Barbara Lea

Glaciers around the globe are experiencing a notable retreat and thinning, triggered by atmospheric warming. Tidewater glaciers in particular have received much attention, because they have been recognized to contribute substantially to global sea level rise. However, lake calving glaciers in Alaska show increasingly high thinning and retreat rates and are therefore contributors to sea level rise. The number of such lake calving systems is increasing worldwide as land-terminating glaciers retreat into overdeepened basins and form proglacial lakes. Yakutat Glacier in Southeast Alaska is a low elevation lake calving glacier with an accumulation to total area ratio of 0.03. It experienced rapid thinning of 4.43 +/- 0.06 m w.e. yr-1 between 2000-2010 and terminus retreat of over 15 km since the beginning of the 20th century. Simultaneously, adjacent Yakutat Icefield land-terminating glaciers thinned at lower but still substantial rates (3.54 +/- 0.06 m w.e. yr -1 for the same time period), indicating lake calving dynamics help drive increased mass loss. Yakutat Glacier sustained a ˜3 km long floating tongue for over a decade, which started to disintegrate into large tabular icebergs in 2010. Such floating tongues are rarely seen on temperate tidewater glaciers. The floating ice was weakened by surface ablation, which then allowed rifts to form and intersect. Ice velocity from GPS measurements showed that the ice on the floating tongue was moving substantially faster than grounded ice, which was attributed to rift opening between the floating and grounded ice. Temporal variations of rift opening were determined from time-lapse imagery, and correlated well with variations in ice speeds. Larger rift opening rates occurred during and after precipitation or increased melt episodes. Both of these events increased subglacial discharge and could potentially increase the subaqueous currents towards the open lake and thus increase drag on the ice underside. Simultaneously

Genetic Underpinnings of Alopecia Areata

Medline Plus

Full Text Available ... Scientific Retreats Scientific and lay representatives discuss needs, gaps, and opportunities in the biomedical research community. Roundtable Discussions The NIAMS holds annual roundtable ...

Removal of root filling materials.

LENUS (Irish Health Repository)

Duncan, H.F. Chong, B.S.

2011-05-01

Safe, successful and effective removal of root filling materials is an integral component of non-surgical root canal re-treatment. Access to the root canal system must be achieved in order to negotiate to the canal terminus so that deficiencies in the original treatment can be rectified. Since a range of materials have been advocated for filling root canals, different techniques are required for their removal. The management of commonly encountered root filling materials during non-surgical re-treatment, including the clinical procedures necessary for removal and the associated risks, are reviewed. As gutta-percha is the most widely used and accepted root filling material, there is a greater emphasis on its removal in this review.

The efficacy of two rotary NiTi instruments and H-files to remove gutta-percha from root canals

Science.gov (United States)

Akpınar, Kerem E.; Altunbaş, Demet

2012-01-01

Objective: The aim of this study was to evaluate the efficacy of R-Endo® and K3® rotary nickel-titanium instruments compared with manual instrumentation with H-files, with use of a solvent, for removal of gutta-percha during retreatment. Study design: Forty five freshly extracted human single-rooted teeth, each with one root canal, were instrumented with K-files and filled using cold lateral compaction of gutta-percha and AH 26® sealer. The teeth were randomly divided into three groups of 15 specimens each. Removal of gutta-percha was performed with the following devices and techniques: Group 1 (H-files), Group 2 (R-Endo®), and Group 3 (K3®). The specimens were rendered transparent for the evaluation of the area of remaining gutta-percha/sealer in buccolingual and mesiodistal directions. Statistical analysis as performed by using one-way ANOVA and Kruskal-Wallis tests (p=0.05). Results: All retreatment techniques used in this study left some filling material inside the root canal. Images in buccolingual and mesiodistal directions showed no significant differences between the groups (p>0.05). Conclusions: Under the experimental conditions, the remaining filling material after retreatment was similar for each group. Key words:Gutta-percha removal, K3®, NiTi, R-Endo®. PMID:22143729

Unicameral bone cyst: a retrospective study of three surgical treatments.

Science.gov (United States)

Sung, Anthony D; Anderson, Megan E; Zurakowski, David; Hornicek, Francis J; Gebhardt, Mark C

2008-10-01

Between 1979 and 2004, 167 patients younger than 20 years were treated surgically for humeral or femoral unicameral bone cysts with either injection of corticosteroids (steroids), curettage plus bone grafting (curettage), or a combination injection of steroids, demineralized bone matrix, and bone marrow aspirate (SDB) at Children's Hospital of Boston and Massachusetts General Hospital (mean followup, 7.3 years; range, 1 month-27 years). Outcomes included treatment failure (defined clinically as subsequent pathologic fracture or need for retreatment to prevent pathologic fracture) and complications. Information was obtained from medical records and by telephone questionnaire. After one treatment, 84% of cysts treated with steroids experienced failed treatment versus 64% with curettage and 50% with SDB. For unicameral bone cysts requiring retreatment (regardless of first treatment), 76% retreated with steroids had failed treatment versus 63% with curettage and 71% with SDB. Curettage was associated with the lowest rate of posttreatment pathologic fractures and highest rate of pain and other complications. Multivariate logistic regression indicated treatment with steroids alone and younger age were independent predictors of failure. We believe SDB is a reasonable first treatment for unicameral bone cysts in the humerus and femur in patients younger than 20 years, being less invasive yet comparable to curettage in preventing recurrence.

Preliminary bathymetry of Blackstone Bay and Neoglacial changes of Blackstone Glaciers, Alaska

Science.gov (United States)

Post, Austin

1980-01-01

Preliminary bathymetry (at 1:20,000 scale) and scientific studies of Blackstone Bay Alaska, by the Research Vessel Growler in 1978 disclose that the head of the bay consists of two basins separated by Willard Island and a submarine ridge. Both basins are closed on the north by terminal-moraine bars where Blackstone Glacier and its tributaries terminated as recently as about A.D. 1350; a carbon-14 date of 580 years before present on Badger Point, and old trees farther up the bay, disclose that the glaciers retreated to two narrow inlets at the head of the bay before 1400. The inlets were still glacier-covered until at least 1909. Glaciers in both inlets have continued to retreat; at present they terminate at the head of tidewater, where they discharge small icebergs. Only relatively thin sediments have accumulated in the eastern basin south of the terminal-moraine bar, and most of the bottom is hard and irregular as disclosed by soundings and profiles. The northern part of Blackstone Bay is very deep; at more than 1,100 feet below sea level a large, level accumulation of sediment is present which is presumably as much as 1,000 feet deep and has been accumulating since late Pleistocene glaciers retreated. (USGS)

Patterns and potential drivers of dramatic changes in Tibetan lakes, 1972-2010.

Science.gov (United States)

Li, Yingkui; Liao, Jingjuan; Guo, Huadong; Liu, Zewen; Shen, Guozhuang

2014-01-01

Most glaciers in the Himalayas and the Tibetan Plateau are retreating, and glacier melt has been emphasized as the dominant driver for recent lake expansions on the Tibetan Plateau. By investigating detailed changes in lake extents and levels across the Tibetan Plateau from Landsat/ICESat data, we found a pattern of dramatic lake changes from 1970 to 2010 (especially after 2000) with a southwest-northeast transition from shrinking, to stable, to rapidly expanding. This pattern is in distinct contrast to the spatial characteristics of glacier retreat, suggesting limited influence of glacier melt on lake dynamics. The plateau-wide pattern of lake change is related to precipitation variation and consistent with the pattern of permafrost degradation induced by rising temperature. More than 79% of lakes we observed on the central-northern plateau (with continuous permafrost) are rapidly expanding, even without glacial contributions, while lakes fed by retreating glaciers in southern regions (with isolated permafrost) are relatively stable or shrinking. Our study shows the limited role of glacier melt and highlights the potentially important contribution of permafrost degradation in predicting future water availability in this region, where understanding these processes is of critical importance to drinking water, agriculture, and hydropower supply of densely populated areas in South and East Asia.

Memories of Serbian victims under Bulgarian occupation in Leskovački glasnik (1915-1918

Directory of Open Access Journals (Sweden)

Antić Dejan D.

2015-01-01

Full Text Available The Serbian army was forced to retreat towards Metohija and Albania eventually due to the armed aggression and attacks from the north and east in October 1915 by the united forces of the German and Austro-Hungarian units against the Kingdom of Serbia. Together with the army, the monarch, executive and legislative branch, intellectuals and civilians also retreated, not wanting to fall in the hands of the incoming army formations of the Central Powers. Following the retreat of the government and army bodies, the territory of the Kingdom of Serbia found itself under the control of the enemy forces, which started the 3-year period of occupation. The subject of this paper are the texts written by the newspaper called Leskovački glasnik (Leskovac Messenger in the period between World War I and World War II, which dealt with the sufferings of the Serbian civilians in the Bulgarian occupied zone from 1915 to 1918. Special attention is paid to the Leskovački glasnik's reports about marking the anniversary of the Bulgarian terror and killings of Serbs, about opening and consecration of memorials, about the heroic deeds and the tragic destiny of the people in south Serbia.

Modelling historical and recent mass loss of McCall Glacier, Alaska, USA

Directory of Open Access Journals (Sweden)

C. Delcourt

2008-03-01

Full Text Available Volume loss of valley glaciers is now considered to be a significant contribution to sea level rise. Understanding and identifying the processes involved in accelerated mass loss are necessary to determine their impact on the global system. Here we present results from a series of model experiments with a higher-order thermomechanically coupled flowline model (Pattyn, 2002. Boundary conditions to the model are parameterizations of surface mass balance, geothermal heating, observed surface and 10 m ice depth temperatures. The time-dependent experiments aim at simulating the glacier retreat from its LIA expansion to present according to different scenarios and model parameters. Model output was validated against measurements of ice velocity, ice surface elevation and terminus position at different stages. Results demonstrate that a key factor in determining the glacier retreat history is the importance of internal accumulation (>50% in the total mass balance. The persistence of a basal temperate zone characteristic for this polythermal glacier depends largely on its contribution. Accelerated glacier retreat since the early nineties seems directly related to the increase in ELA and the sudden reduction in AAR due to the fact that a large lower elevation cirque – previously an important accumulation area – became part of the ablation zone.

Laboratory testing of a room temperature separation technique as part of a method for the reconditioning of bituminised waste

International Nuclear Information System (INIS)

Impens, N.

2009-01-01

At the Belgian Nuclear Research Center SCK-CEN, a research project has been finalised on the possible alternatives to re-treat so-called homogeneous bituminised waste such as Eurobitum. One way to retreat this type of waste would be plasma-incineration. Preliminary results showed that a very stable final vitrified waste can be obtained comparable to the stability of R7-T7 reference waste glass, and that the waste volume would be reduced to 75 percent of the original volume. The major disadvantages of this retreatment technique is the high-tech and high cost plasma installation needed and the safety aspects related to the higher radioactivity content of this waste type. The technique proposed in this paper is based on the dissolution of the bitumen in an organic solvent and the subsequent extraction of nitrates in water leading to the separation of (1) an organic effluent containing the maltenes, (2) an aqueous effluent containing the nitrates and (3) the final waste containing the asphaltene fraction and water insoluble salts including most of the radionuclides. This paper describes the lab-scale results of a room temperature separation technique applied to real radioactive Eurobitum samples, sampled from a drum that was produced in 1981

Bacterial diversity in the foreland of the Tianshan No. 1 glacier, China

International Nuclear Information System (INIS)

Wu Xiukun; Zhang Wei; Liu Guangxiu; Zhang Gaosen; Yang Xuan; Hu Ping; Chen Tuo; Li Zhongqin

2012-01-01

There is compelling evidence that glaciers are retreating in many mountainous areas of the world due to global warming. With this glacier retreat, new habitats are being exposed that are colonized by microorganisms whose diversity and function are less well studied. Here, we characterized bacterial diversity along the chronosequences of the glacier No. 1 foreland that follows glacier retreat. An average of 10 000 sequences was obtained from each sample by 454 pyrosequencing. Using non-parametric and rarefaction estimated analysis, we found bacterial phylotype richness was high. The bacterial species turnover rate was especially high between sites exposed for 6 and 10 yr. Pyrosequencing showed tremendous bacterial diversity, among which the Acidobacteria, Actinobacteria, Bacteroidetes and Proteobacteria were found to be present at larger numbers at the study area. Meanwhile, the proportion of Bacteroidetes and Proteobacteria decreased and the proportion of Acidobacteria increased along the chronosequences. Some known functional bacterial genera were also detected and the sulfur- and sulfate-reducing bacteria were present in a lower proportion of sequences. These findings suggest that high-throughput pyrosequencing can comprehensively detect bacteria in the foreland, including rare groups, and give a deeper understanding of the bacterial community structure and variation along the chronosequences. (letter)

Bacterial diversity in the foreland of the Tianshan No. 1 glacier, China

Energy Technology Data Exchange (ETDEWEB)

Xiukun, Wu; Wei, Zhang; Guangxiu, Liu; Gaosen, Zhang [Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou (China); Xuan, Yang; Ping, Hu [School of Chemical and Biological Engineering, Lanzhou Jiaotong University, Lanzhou (China); Tuo, Chen; Li Zhongqin, E-mail: liugx@lzb.ac.cn [State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou (China)

2012-03-15

There is compelling evidence that glaciers are retreating in many mountainous areas of the world due to global warming. With this glacier retreat, new habitats are being exposed that are colonized by microorganisms whose diversity and function are less well studied. Here, we characterized bacterial diversity along the chronosequences of the glacier No. 1 foreland that follows glacier retreat. An average of 10 000 sequences was obtained from each sample by 454 pyrosequencing. Using non-parametric and rarefaction estimated analysis, we found bacterial phylotype richness was high. The bacterial species turnover rate was especially high between sites exposed for 6 and 10 yr. Pyrosequencing showed tremendous bacterial diversity, among which the Acidobacteria, Actinobacteria, Bacteroidetes and Proteobacteria were found to be present at larger numbers at the study area. Meanwhile, the proportion of Bacteroidetes and Proteobacteria decreased and the proportion of Acidobacteria increased along the chronosequences. Some known functional bacterial genera were also detected and the sulfur- and sulfate-reducing bacteria were present in a lower proportion of sequences. These findings suggest that high-throughput pyrosequencing can comprehensively detect bacteria in the foreland, including rare groups, and give a deeper understanding of the bacterial community structure and variation along the chronosequences. (letter)

Patient- and provider-level risk factors associated with default from tuberculosis treatment, South Africa, 2002: a case-control study.

Science.gov (United States)

Finlay, Alyssa; Lancaster, Joey; Holtz, Timothy H; Weyer, Karin; Miranda, Abe; van der Walt, Martie

2012-01-20

Persons who default from tuberculosis treatment are at risk for clinical deterioration and complications including worsening drug resistance and death. Our objective was to identify risk factors associated with tuberculosis (TB) treatment default in South Africa. We conducted a national retrospective case control study to identify factors associated with treatment default using program data from 2002 and a standardized patient questionnaire. We defined default as interrupting TB treatment for two or more consecutive months during treatment. Cases were a sample of registered TB patients receiving treatment under DOTS that defaulted from treatment. Controls were those who began therapy and were cured, completed or failed treatment. Two respective multivariable models were constructed, stratified by history of TB treatment (new and re-treatment patients), to identify independent risk factors associated with default. The sample included 3165 TB patients from 8 provinces; 1164 were traceable and interviewed (232 cases and 932 controls). Significant risk factors associated with default among both groups included poor health care worker attitude (new: AOR 2.1, 95% CI 1.1-4.4; re-treatment: AOR 12, 95% CI 2.2-66.0) and changing residence during TB treatment (new: AOR 2.0, 95% CI 1.1-3.7; re-treatment: AOR 3.4, 95% CI 1.1-9.9). Among new patients, cases were more likely than controls to report having no formal education (AOR 2.3, 95% CI 1.2-4.2), feeling ashamed to have TB (AOR 2.0, 95% CI 1.3-3.0), not receiving adequate counseling about their treatment (AOR 1.9, 95% CI 1.2-2.8), drinking any alcohol during TB treatment (AOR 1.9, 95% CI 1.2-3.0), and seeing a traditional healer during TB treatment (AOR 1.9, 95% CI 1.1-3.4). Among re-treatment patients, risk factors included stopping TB treatment because they felt better (AOR 21, 95% CI 5.2-84), having a previous history of TB treatment default (AOR 6.4, 95% CI 2.9-14), and feeling that food provisions might have helped

A comparative evaluation of gutta percha removal and extrusion of apical debris by rotary and hand files.

Science.gov (United States)

Chandrasekar; Ebenezar, A V Rajesh; Kumar, Mohan; Sivakumar, A

2014-11-01

The aim of this study was to evaluate the efficacy of Protaper retreatment files in comparison with RaCe, K3 and H-files for removal of gutta-percha and apically extruded debris using volumetric analysis. Forty extracted single rooted maxillary incisor teeth with straight canals and mature apices were selected for the study. After access cavity preparation, apical patency was confirmed with a size 10 K-file extending 1mm beyond the point at which it was first visible at the apical end. Working lengths were determined with the use of size 15 K-file. The canals were prepared in a step-back technique and the master apical file was size 30 for all teeth. 3% sodium hypochlorite was used as an irrigant after each instrumentation. Before final rinse, size 20 K-file was passed 1mm beyond the apex to remove any dentinal shaving plugs and maintain the apical patency. Then the canals were dried with paper points. The root canal was filled using standard gutta-percha points and zinc oxide eugenol sealer under lateral condensation technique. The teeth were then randomly divided into four groups of ten teeth each based on the instrument used for gutta percha removal. All the rotary instruments used in this study were rotated at 300rpm. The instruments used were: Group 1 - RaCe Files, Group 2 - ProTaper retreatment Files, Group 3 - K3 Files and Group 4 - H Files. The volume of the obturating material was calculated before and after removal using volumetric analysis with spiral CT. The removal efficacy with each instrument was calculated and statistically analysed. The results of the study show that the ProTaper retreatment files (Group 2) (97.4%) showed the highest efficiency in the removal of obturating material, which was followed by RaCe (95.74%), K3 (92.86%) and H files (90.14%) with the efficiency in the decreasing order. Similarly the mean apical extrusion in H files (0.000 ± 0.002) was significantly lower than all the rotary instruments. However, the difference among the

Site-Specific Bluff Recession Rates Measured on the Alaskan Beaufort Sea Coast

Science.gov (United States)

Richmond, B.; Gadd, P.; Crowell, W.

2017-12-01

OverviewThe effects of climate change are being studied globally with coastal erosion in Arctic regions of particular concern. In support of Hilcorp Alaska's Northstar Development, short- and long-term bluff recession rates have been documented at a pipeline shore crossing located in Gwydyr Bay on the Alaskan Beaufort Sea coast. These data are presented, along with the predominant forcing mechanisms, and compared to local and regional recession rates recently published by the U.S. Geological Survey (USGS). Arctic Bluff RecessionCoastal retreat along the northern coast of Alaska occurs at two different rates: infrequent, but rapid erosion induced by strong westerly storms, and seasonal retreat related to thawing and sediment removal under more moderate wave conditions. Variability in the rate of bluff retreat is related to a number of factors, including bluff composition (ice content and sediment type), existence of a fronting beach, and wave exposure. Measured Bluff Recession at the Northstar Pipeline Shore CrossingThe location of the Northstar Development pipeline shore crossing was chosen based on analysis of historical aerial photos acquired between 1949 and 1996. Over this 47-year period, the average annualized rate of bluff retreat in the study area ranged from 1.6 to 3.0 ft/yr. Beginning in 1996, ground-based shoreline monitoring surveys have been conducted along the bluff and ten shore-perpendicular transects at the site. The rates of bluff retreat derived from the survey data have been modest, ranging from no change to 5.8 ft/yr. The monitoring surveys indicate that waves and currents erode the bluffs by direct impact only during infrequent, but strong westerly storms that promote a short-term rise in sea level (storm surge). The more prevalent easterly storms can cause set-down, or reduction in the sea level which limits direct wave impact on the bluff, thereby decreasing the potential for wave induced erosion. Comparative StudiesRecent studies conducted

Geophysical monitoring of coastal erosion and cliff retreat of ...

African Journals Online (AJOL)

Monitoring of the coastal zone is necessary to assess its vulnerability and help formulate coastal management plans. A predetermined stretch of beach along the northern rim of False Bay known locally as Monwabisi Beach was chosen to compare different monitoring techniques and from the data acquired, see if accurate ...

Geophysical monitoring of coastal erosion and cliff retreat of ...

African Journals Online (AJOL)

Michael.Machutchon

affected by deep ocean swells generated from the southwest and south ... system where a GPS antenna height is used to define the shape of shore perpendicular transects. In ... data from these devices were acquired and processed using Qinsy and Fledermaus software. .... long period swells with a shallow wave base.

Connecticut School Integration: Moving Forward as the Northeast Retreats

Science.gov (United States)

Orfield, Gary

2015-01-01

This report analyzes the data on changes in patterns of racial segregation and their education consequences over a quarter century, from l987 to 2012. It examines a major transition in the racial and ethnic composition of Connecticut and the changes in integration and segregation in the schools of the state and its urban communities and it…

The Diabetic Foot Attack: "'Tis Too Late to Retreat!"

Science.gov (United States)

Vas, Prashanth R J; Edmonds, Michael; Kavarthapu, Venu; Rashid, Hisham; Ahluwalia, Raju; Pankhurst, Christian; Papanas, Nikolaos

2018-03-01

The "diabetic foot attack" is one of the most devastating presentations of diabetic foot disease, typically presenting as an acutely inflamed foot with rapidly progressive skin and tissue necrosis, at times associated with significant systemic symptoms. Without intervention, it may escalate over hours to limb-threatening proportions and poses a high amputation risk. There are only best practice approaches but no international protocols to guide management. Immediate recognition of a typical infected diabetic foot attack, predominated by severe infection, with prompt surgical intervention to debride all infected tissue alongside broad-spectrum antibiotic therapy is vital to ensure both limb and patient survival. Postoperative access to multidisciplinary and advanced wound care therapies is also necessary. More subtle forms exist: these include the ischemic diabetic foot attack and, possibly, in a contemporary categorization, acute Charcot neuroarthropathy. To emphasize the importance of timely action especially in the infected and ischemic diabetic foot attack, we revisit the concept of "time is tissue" and draw parallels with advances in acute myocardial infarction and stroke care. At the moment, international protocols to guide management of severe diabetic foot presentations do not specifically use the term. However, we believe that it may help increase awareness of the urgent actions required in some situations.

Catalog of NASA-Related Case Studies

Data.gov (United States)

National Aeronautics and Space Administration — The OCKO has developed over 50 case studies to enhance learning at workshops, training, retreats and conferences. Case studies make mission knowledge attractive and...

Double palatal roots in maxillary second molars: A case report and literature review

Directory of Open Access Journals (Sweden)

Mohammed S Alenazy

2015-01-01

Full Text Available A thorough understanding of internal and external anatomy of various teeth is critical for a successful outcome of endodontic therapy. The aims of this paper were (1 to describe the clinical retreatment of a maxillary second molar with two palatal roots and (2 to review the available literature regarding this anatomical variation. A 45-year-old Saudi female presented for non-surgical retreatment of maxillary left second molar. Careful radiographic and clinical examinations revealed the presence of two buccal and two palatal roots each with a single root canal. Anatomical variations can occur in any tooth; therefore, the clinicians should always anticipate the occurrence of these variations and utilize all the available tools to diagnose and manage them

"Deja Vu All over Again" Initiatives in Academic Management.

Science.gov (United States)

Bilik, Laurie J.; Blum, Mark C.

1989-01-01

While colleges and universities are increasingly retreating to management models already considered counterproductive in industry, corporations are beginning to appreciate the principles of shared authority and are developing collegial-style cultures. (MSE)

Estimating Selected Disease and Non-Battle Injury Echelon I and Echelon II Outpatient Visits of U.S. Soldiers and Marines in an Operational Setting from Corresponding Echelon III (Hospitalization) Admissions in the Same Theater of Operation

National Research Council Canada - National Science Library

Kilian, Dennis B

2000-01-01

.... This has been demonstrated throughout history from Napoleon's typhus outbreak in the retreat from Moscow, to Merrill's Maraders' dysentery outbreak in Burma, and to the US Forces-Somalia dengue and malaria outbreak...

Dewetting at the edge of a thin NiO-film on Si by swift heavy ion irradiation

International Nuclear Information System (INIS)

Dautel, Knut; Ferhati, Redi; Bolse, Wolfgang

2014-01-01

We have investigated dewetting along a straight edge of a thin NiO-film on a Si-wafer induced by irradiation with 4.8 MeV/u Au-ions at room temperature. Both, the retreat of the edge as well as the opening and growth of circular holes in the film were monitored using our in-situ high resolution scanning electron microscope at the UNILAC accelerator at the Helmholtz Centre for Heavy Ion Research in Darmstadt. The “dewetting kinetics” (dependence of the retreated length and the hole radius on the ion fluence) are compared to previously published results on dewetting of poly-crystalline (Au) and glassy (polymer) films. In the present case the dewetting kinetics compare well with those observed for isothermal dewetting of the highly viscous polymer films, presumed that the role of time in thermally induced dewetting is taken over by the ion fluence in ion induced dewetting. Both, from the dewetting kinetics and the shape of the remaining NiO-traces in the dewetted area in front of the retreating edge, we conclude that the presently observed swift heavy ion induced dewetting occurs by interfacial slipping. It occurs in spatially and timely separated steps in the transiently molten single ion tracks, where the required reduction of the viscosity of NiO is achieved

Dewetting at the edge of a thin NiO-film on Si by swift heavy ion irradiation

Energy Technology Data Exchange (ETDEWEB)

Dautel, Knut; Ferhati, Redi; Bolse, Wolfgang, E-mail: w.bolse@ihfg.uni-stuttgart.de

2014-01-01

We have investigated dewetting along a straight edge of a thin NiO-film on a Si-wafer induced by irradiation with 4.8 MeV/u Au-ions at room temperature. Both, the retreat of the edge as well as the opening and growth of circular holes in the film were monitored using our in-situ high resolution scanning electron microscope at the UNILAC accelerator at the Helmholtz Centre for Heavy Ion Research in Darmstadt. The “dewetting kinetics” (dependence of the retreated length and the hole radius on the ion fluence) are compared to previously published results on dewetting of poly-crystalline (Au) and glassy (polymer) films. In the present case the dewetting kinetics compare well with those observed for isothermal dewetting of the highly viscous polymer films, presumed that the role of time in thermally induced dewetting is taken over by the ion fluence in ion induced dewetting. Both, from the dewetting kinetics and the shape of the remaining NiO-traces in the dewetted area in front of the retreating edge, we conclude that the presently observed swift heavy ion induced dewetting occurs by interfacial slipping. It occurs in spatially and timely separated steps in the transiently molten single ion tracks, where the required reduction of the viscosity of NiO is achieved.

Balance of the West Antarctic Ice Sheet

Science.gov (United States)

2002-01-01

For several decades, measurements of the West Antarctic Ice Sheet showed it to be retreating rapidly. But new data derived from satellite-borne radar sensors show the ice sheet to be growing. Changing Antarctic ice sheets remains an area of high scientific interest, particularly in light of recent global warming concerns. These new findings are significant because scientists estimate that sea level would rise 5-6 meters (16-20 feet) if the ice sheet collapsed into the sea. Do these new measurements signal the end of the ice sheet's 10,000-year retreat? Or, are these new satellite data simply much more accurate than the sparse ice core and surface measurements that produced the previous estimates? Another possibility is that the ice accumulation may simply indicate that the ice sheet naturally expands and retreats in regular cycles. Cryologists will grapple with these questions, and many others, as they examine the new data. The image above depicts the region of West Antarctica where scientists measured ice speed. The fast-moving central ice streams are shown in red. Slower tributaries feeding the ice streams are shown in blue. Green areas depict slow-moving, stable areas. Thick black lines depict the areas that collect snowfall to feed their respective ice streams. Reference: Ian Joughin and Slawek Tulaczyk Science Jan 18 2002: 476-480. Image courtesy RADARSAT Antarctic Mapping Project

The Radiotherapy Result of the Nasopharyngeal Carcinoma

International Nuclear Information System (INIS)

Park, Charn Il; Koh, Kyoung Hwan; Kim, Chong Sun; Kim, Noe Kyeong

1983-01-01

A total of 47 patients with a diagnosis of nasopharyngeal carcinoma was treated in Department of Therapeutic Radiology, Seoul National University Hospital during last 4 years. Of the 47 patients, 23(49%) had undifferentiated carcinoma, 20(43%) had squamous cell carcinoma, while 4(8%) had lymphoepithelioma. Most of the patients(71%) has Stage IV disease, cervical lymph node metastases were found in 36(77%) and distant metastasis was found in 1 at the time of diagnosis. Complete response rate after radiotherapy for 47 patients of nasopharyngeal carcinoma was 85.1%. The overall actuarial 3 year survival rates was 0.718 and the disease free actuarial 3 year survival rates was 0.468. Nodal involvement and symptom duration were statistically significant influencing factors for actuarial survival rate. Treatment failures were found in 20 patients (42.6%), local recurrence only in 6(30%), local and neck recurrence in 3(15%), local recurrence with metastasis in 4(20%) and distant metastasis only in 7(35%). Local failures were more frequent in the patients with cranial nerve symptoms (P=0.032). Distant metastases were more frequent with T4 lesions (P=0.047), and with nodal involvement (P<0.01). Retreatment after the tumor recurrence was chemotherapy and/or radiotherapy, two patients retreated for local recurrence were alive without evidence of disease for more than 19 and 44 months after retreatment

Ten years after photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) for moderate to high myopia (control-matched study).

Science.gov (United States)

Alió, J L; Ortiz, D; Muftuoglu, O; Garcia, M J

2009-10-01

To compare the long-term outcomes of photorefractive keratectomy (PRK) and laser in situ keratomilesis (LASIK) for myopia between -6 and -10 D. A retrospective, control-matched study including 68 eyes, 34 which underwent PRK and 34 LASIK, with myopia between -6 and -10 D, operated using the VISX 20/20 excimer laser, was performed. Optical zones of 5.5 to 6 mm were used. All PRK-treated eyes were matched with LASIK-treated eyes of the same age, spherical equivalent within +/-1.25 D, sphere within +/-1.5 D and cylinder within +/-2.5 D. All patients were evaluated 3 months, 1 year, 2 years, 5 years and 10 years after surgery. The main outcomes measures were refractive predictability and stability, safety, efficacy and re-treatment rate. At 10 years, 20 (71%) and 23 (88%) were within +/-1.00 D after PRK and LASIK respectively. The re-treatment rate was 35% and 18% respectively. No eye lost more than two lines of BSCVA in both groups. The efficacy was 0.90 for PRK and 0.95 for LASIK. Both PRK and LASIK were safe for moderate myopia. LASIK demonstrated slightly better efficacy, predictability, and less rate of re-treatment after 10 years. The technical improvements should be taken into account when comparing these results with those obtained more recently.

Cytogenetic biodosimetry and dose-rate effect after radioiodine therapy for thyroid cancer

Energy Technology Data Exchange (ETDEWEB)

Khvostunov, Igor K. [Russian Ministry of Health Care, A.F. Tsyb Medical Radiological Research Center, Branch of the National Medical Research Radiological Centre, Obninsk, Kaluga Region (Russian Federation); Nagasaki University, Department of Radiation Molecular Epidemiology, Atomic Bomb Disease Institute, Nagasaki (Japan); Saenko, Vladimir A.; Yamashita, Shunichi [Nagasaki University, Department of Radiation Molecular Epidemiology, Atomic Bomb Disease Institute, Nagasaki (Japan); Krylov, Valeri; Rodichev, Andrei [Russian Ministry of Health Care, A.F. Tsyb Medical Radiological Research Center, Branch of the National Medical Research Radiological Centre, Obninsk, Kaluga Region (Russian Federation)

2017-08-15

This study set out to investigate chromosomal damage in peripheral blood lymphocytes of thyroid cancer patients receiving {sup 131}I for thyroid remnant ablation or treatment of metastatic disease. The observed chromosomal damage was further converted to the estimates of whole-body dose to project the adverse side effects. Chromosomal aberration analysis was performed in 24 patients treated for the first time or after multiple courses. Blood samples were collected before treatment and 3 or 4 days after administration of 2-4 GBq of {sup 131}I. Both conventional cytogenetic and chromosome 2, 4 and 12 painting assays were used. To account for dose-rate effect, a dose-protraction factor was applied to calculate the whole-body dose. The mean dose was 0.62 Gy (95% CI: 0.44-0.77 Gy) in the subgroup of patients treated one time and 0.67 Gy (95% CI: 0.03-1.00 Gy) in re-treated patients. These dose estimates are about 1.7-fold higher than those disregarding the effect of exposure duration. In re-treated patients, the neglected dose-rate effect can result in underestimation of the cumulative whole-body dose by the factor ranging from 2.6 to 6.8. Elevated frequency of chromosomal aberrations observed in re-treated patients before radioiodine therapy allows estimation of a cumulative dose received from all previous treatments. (orig.)

Association between Empirically Estimated Monsoon Dynamics and Other Weather Factors and Historical Tea Yields in China: Results from a Yield Response Model

Directory of Open Access Journals (Sweden)

Rebecca Boehm

2016-04-01

Full Text Available Farmers in China’s tea-growing regions report that monsoon dynamics and other weather factors are changing and that this is affecting tea harvest decisions. To assess the effect of climate change on tea production in China, this study uses historical weather and production data from 1980 to 2011 to construct a yield response model that estimates the partial effect of weather factors on tea yields in China, with a specific focus on East Asian Monsoon dynamics. Tea (Camellia sinensis (L. Kunze has not been studied using these methods even though it is an important crop for human nutrition and the economic well-being of rural communities in many countries. Previous studies have approximated the monsoon period using historical average onset and retreat dates, which we believe limits our understanding of how changing monsoon patterns affect crop productivity. In our analysis, we instead estimate the monsoon season across China’s tea growing regions empirically by identifying the unknown breakpoints in the year-by-province cumulative precipitation. We find that a 1% increase in the monsoon retreat date is associated with 0.481%–0.535% reduction in tea yield. In the previous year, we also find that a 1% increase in the date of the monsoon retreat is associated with a 0.604% decrease in tea yields. For precipitation, we find that a 1% increase in average daily precipitation occurring during the monsoon period is associated with a 0.184%–0.262% reduction in tea yields. In addition, our models show that 1% increase in the average daily monsoon precipitation from the previous growing season is associated with 0.258%–0.327% decline in yields. We also find that a 1% decrease in solar radiation in the previous growing season is associated with 0.554%-0.864% decrease in tea yields. These findings suggest the need for adaptive management and harvesting strategies given climate change projections and the known negative association between excess

Conduit enlargement in an eogenetic karst aquifer

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Moore, Paul J.; Martin, Jonathan B.; Screaton, Elizabeth J.; Neuhoff, Philip S.

2010-11-01

SummaryMost concepts of conduit development have focused on telogenetic karst aquifers, where low matrix permeability focuses flow and dissolution along joints, fractures, and bedding planes. However, conduits also exist in eogenetic karst aquifers, despite high matrix permeability which accounts for a significant component of flow. This study investigates dissolution within a 6-km long conduit system in the eogenetic Upper Floridan aquifer of north-central Florida that begins with a continuous source of allogenic recharge at the Santa Fe River Sink and discharges from a first-magnitude spring at the Santa Fe River Rise. Three sources of water to the conduit include the allogenic recharge, diffuse recharge through epikarst, and mineralized water upwelling from depth. Results of sampling and inverse modeling using PHREEQC suggest that dissolution within the conduit is episodic, occurring only during 30% of 16 sampling times between March 2003 and April 2007. During low flow conditions, carbonate saturated water flows from the matrix to the conduit, restricting contact between undersaturated allogenic water with the conduit wall. When gradients reverse during high flow conditions, undersaturated allogenic recharge enters the matrix. During these limited periods, estimates of dissolution within the conduit suggest wall retreat averages about 4 × 10 -6 m/day, in agreement with upper estimates of maximum wall retreat for telogenetic karst. Because dissolution is episodic, time-averaged dissolution rates in the sink-rise system results in a wall retreat rate of about 7 × 10 -7 m/day, which is at the lower end of wall retreat for telogenetic karst. Because of the high permeability matrix, conduits in eogenetic karst thus enlarge not just at the walls of fractures or pre-existing conduits such as those in telogenetic karst, but also may produce a friable halo surrounding the conduits that may be removed by additional mechanical processes. These observations stress the

Mean-field thalamocortical modeling of longitudinal EEG acquired during intensive meditation training.

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Saggar, Manish; Zanesco, Anthony P; King, Brandon G; Bridwell, David A; MacLean, Katherine A; Aichele, Stephen R; Jacobs, Tonya L; Wallace, B Alan; Saron, Clifford D; Miikkulainen, Risto

2015-07-01

Meditation training has been shown to enhance attention and improve emotion regulation. However, the brain processes associated with such training are poorly understood and a computational modeling framework is lacking. Modeling approaches that can realistically simulate neurophysiological data while conforming to basic anatomical and physiological constraints can provide a unique opportunity to generate concrete and testable hypotheses about the mechanisms supporting complex cognitive tasks such as meditation. Here we applied the mean-field computational modeling approach using the scalp-recorded electroencephalogram (EEG) collected at three assessment points from meditating participants during two separate 3-month-long shamatha meditation retreats. We modeled cortical, corticothalamic, and intrathalamic interactions to generate a simulation of EEG signals recorded across the scalp. We also present two novel extensions to the mean-field approach that allow for: (a) non-parametric analysis of changes in model parameter values across all channels and assessments; and (b) examination of variation in modeled thalamic reticular nucleus (TRN) connectivity over the retreat period. After successfully fitting whole-brain EEG data across three assessment points within each retreat, two model parameters were found to replicably change across both meditation retreats. First, after training, we observed an increased temporal delay between modeled cortical and thalamic cells. This increase provides a putative neural mechanism for a previously observed reduction in individual alpha frequency in these same participants. Second, we found decreased inhibitory connection strength between the TRN and secondary relay nuclei (SRN) of the modeled thalamus after training. This reduction in inhibitory strength was found to be associated with increased dynamical stability of the model. Altogether, this paper presents the first computational approach, taking core aspects of physiology and

Constraining the Antarctic contribution to global sea-level change: ANDRILL and beyond

Science.gov (United States)

Naish, Timothy

2016-04-01

Observations, models and paleoclimate reconstructions suggest that Antarctica's marine-based ice sheets behave in an unstable manner with episodes of rapid retreat in response to warming climate. Understanding the processes involved in this "marine ice sheet instability" is key for improving estimates of Antarctic ice sheet contribution to future sea-level rise. Another motivating factor is that far-field sea-level reconstructions and ice sheet models imply global mean sea level (GMSL) was up to 20m and 10m higher, respectively, compared with present day, during the interglacials of the warm Pliocene (~4-3Ma) and Late Pleistocene (at ~400ka and 125ka). This was when atmospheric CO2 was between 280 and 400ppm and global average surface temperatures were 1 to 3°C warmer, suggesting polar ice sheets are highly sensitive to relatively modest increases in climate forcing. Such magnitudes of GMSL rise not only require near complete melt of the Greenland Ice Sheet and the West Antarctic Ice Sheet, but a substantial retreat of marine-based sectors of East Antarctic Ice Sheet. Recent geological drilling initiatives on the continental margin of Antarctica from both ship- (e.g. IODP; International Ocean Discovery Program) and ice-based (e.g. ANDRILL/Antarctic Geological Drilling) platforms have provided evidence supporting retreat of marine-based ice. However, without direct access through the ice sheet to archives preserved within sub-glacial sedimentary basins, the volume and extent of ice sheet retreat during past interglacials cannot be directly constrained. Sediment cores have been successfully recovered from beneath ice shelves by the ANDRILL Program and ice streams by the WISSARD (Whillans Ice Stream Sub-glacial Access Research Drilling) Project. Together with the potential of the new RAID (Rapid Access Ice Drill) initiative, these demonstrate the technological feasibility of accessing the subglacial bed and deeper sedimentary archives. In this talk I will outline the

Constraining the Antarctic contribution to interglacial sea-level rise

Science.gov (United States)

Naish, T.; Mckay, R. M.; Barrett, P. J.; Levy, R. H.; Golledge, N. R.; Deconto, R. M.; Horgan, H. J.; Dunbar, G. B.

2015-12-01

Observations, models and paleoclimate reconstructions suggest that Antarctica's marine-based ice sheets behave in an unstable manner with episodes of rapid retreat in response to warming climate. Understanding the processes involved in this "marine ice sheet instability" is key for improving estimates of Antarctic ice sheet contribution to future sea-level rise. Another motivating factor is that far-field sea-level reconstructions and ice sheet models imply global mean sea level (GMSL) was up to 20m and 10m higher, respectively, compared with present day, during the interglacials of the warm Pliocene (~4-3Ma) and Late Pleistocene (at ~400ka and 125ka). This was when atmospheric CO2 was between 280 and 400ppm and global average surface temperatures were 1- 3°C warmer, suggesting polar ice sheets are highly sensitive to relatively modest increases in climate forcing. Such magnitudes of GMSL rise not only require near complete melt of the Greenland Ice Sheet and the West Antarctic Ice Sheet, but a substantial retreat of marine-based sectors of East Antarctic Ice Sheet. Recent geological drilling initiatives on the continental margin of Antarctica from both ship- (e.g. IODP; International Ocean Discovery Program) and ice-based (e.g. ANDRILL/Antarctic Geological Drilling) platforms have provided evidence supporting retreat of marine-based ice. However, without direct access through the ice sheet to archives preserved within sub-glacial sedimentary basins, the volume and extent of ice sheet retreat during past interglacials cannot be directly constrained. Sediment cores have been successfully recovered from beneath ice shelves by the ANDRILL Program and ice streams by the WISSARD (Whillans Ice Stream Sub-glacial Access Research Drilling) Project. Together with the potential of the new RAID (Rapid Access Ice Drill) initiative, these demonstrate the technological feasibility of accessing the subglacial bed and deeper sedimentary archives. In this talk I will outline the

Emergence of nitrosourea resistant sublines of Lewis lung tumour following MeCCNU treatment in vivo.

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Stephens, T. C.; Adams, K.; Peacock, J. H.

1986-01-01

Several different drug retreatment protocols were employed to examine the emergence of resistance to MeCCNU in Lewis lung tumours. Previous studies suggested that although the majority of cells in untreated Lewis lung tumours were sensitive to MeCCNU, there was a very small proportion of resistant cells (approximately 0.001%) that limited "tumour cure' with that drug. If such cells were inherently drug resistant then it should be possible to derive highly resistant tumours by repeated drug treatment. In the first experiment tumours were treated with a single high dose of MeCCNU (35 or 40 mgkg-1) and on regrowth, transplanted into fresh mice and tested for drug sensitivity. Using both excision cell survival and growth delay endpoints, only approximately 25% of tumours were significantly resistant to the test dose, suggesting that many tumours resist the effects of the drug for reasons other than the presence of inherently drug resistant cells. One of the tumours (R4), that regrew after the initial treatment and appeared to be resistant to the test treatment, was retreated with a further 30 mgkg-1 MeCCNU and became more resistant. This line, designated R4/1, was cross-resistant to the other nitrosoureas, BCNU and CCNU, but not to cyclophosphamide, melphalan, cis-platinum or ionising radiation. The effect of treatment dose on the kinetics of MeCCNU resistance development was also studied in a retreatment regimen where the tumours were allowed to regrow and then transplanted into fresh hosts for the next treatment. Resistance developed more quickly at an intermediate dose of 15 mgkg-1 than at 7.5 mgkg-1 where the selective pressure was lower, or at 30 mgkg-1 where there was probably extinction of partially resistant cells. Resistance to MeCCNU developed even more quickly when tumours were retreated several times in the same host, although in a similar experiment with cyclophosphamide no resistance occurred. PMID:3954945

Hurricane Irma's Effects on Dune and Beach Morphology at Matanzas Inlet, Atlantic Coast of North Florida: Impacts and Inhibited Recovery?

Science.gov (United States)

Adams, P. N.; Conlin, M. P.; Johnson, H. A.; Paniagua-Arroyave, J. F.; Woo, H. B.; Kelly, B. P.

2017-12-01

During energetic coastal storms, surge from low atmospheric pressure, high wave set-up, and increased wave activity contribute to significant morphologic change within the dune and upper beach environments of barrier island systems. Hurricane Irma made landfall on the southwestern portion of the Florida peninsula, as a category 4 storm on Sept 10th, 2017 and tracked northward along the axis of the Florida peninsula for two days before dissipating over the North American continent. Observations along the North Florida Atlantic coast recorded significant wave heights of nearly 7 m and water levels that exceeded predictions by 2 meters on the early morning of Sept. 11th. At Fort Matanzas National Monument, the dune and upper beach adjacent to Matanzas Inlet experienced landward retreat during the storm, diminishing the acreage of dune and scrub habitat for federally-listed endangered and threatened animal species, including the Anastasia beach mouse, gopher tortoises, and several protected shore birds. Real Time Kinematic (RTK) GPS surveys, conducted prior to the passage of the storm (Sept. 8) and immediately after the storm (Sept. 13) document dune scarp retreat >10 m in places and an average retreat of 7.8 m (+/- 5.2 m) of the 2-m beach contour, attributable to the event, within the study region. Although it is typical to see sedimentary recovery at the base of dunes within weeks following an erosive event of this magnitude, our follow up RTK surveys, two weeks (Sept. 26) and five weeks (Oct. 19) after the storm, document continued dune retreat and upper beach lowering. Subsequent local buoy observations during the offshore passage of Hurricanes Jose, Maria (Sept. 17 and 23, respectively) and several early-season Nor'easters recorded wave heights well above normal (2-3 meters) from the northeast. The lack of recovery may reveal a threshold vulnerability of the system, in which the timing of multiple moderate-to-high wave events, in the aftermath of a land falling

Long-term prognosis of endodontically treated teeth: a retrospective analysis of preoperative factors in molars.

Science.gov (United States)

Setzer, Frank C; Boyer, Keith R; Jeppson, Joshua R; Karabucak, Bekir; Kim, Syngcuk

2011-01-01

Long-term predictability of restored endodontically treated teeth is important for the decision of tooth retention versus extraction and implant placement. The purpose of this study was to validate the hypothesis that preoperative factors can predict the long-term prognosis of molars requiring endodontic and restorative treatment for future prognostic investigations. A clinical database was searched for molar endodontic treatments with crown placement and a minimum of 4-year follow-up. Charts of 42 patients with 50 individual treatments were randomly selected. Information concerning crown lengthening; periodontal diagnosis; attachment loss; furcation involvement; mobility; and internal, external, or periradicular resorption was recorded. Radiographs from treatment initiation and follow-up were digitalized. The presence of apical periodontitis was evaluated. Available ferrule was calculated from bitewing radiographs using CAD software (AutoCAD; Autodesk, Cupertino, CA). The resulting data, age, sex, and times of restoration and follow-up were analyzed for correlation with the presence of apical radiolucency at follow-up and the following four possible outcome scenarios: "no event," "nonsurgical retreatment," "surgical retreatment," or "extraction" using Spearman rank order correlation analysis. Patients' ages ranged from 19 to 87 years, 22 were male and 20 female, and 48 teeth (96.0%) were retained at follow-up. Of those, 44 (88.0%) were without intervention ("no event"), and four (8.0%) underwent surgical or nonsurgical retreatment. Two teeth (4.0%) had been extracted. Significant positive correlations existed between "untoward events" (any form of retreatment or extraction) and "prognostic value according to periodontal status" (p = 0.047) and "attachment loss" (p = 0.042). The only preoperative factors significant for the prognosis of restored endodontically treated molars were related to periodontal prognostic value and attachment loss. It can be concluded that

Human Resources Coordinator | IDRC - International Development ...

International Development Research Centre (IDRC) Digital Library (Canada)

... make arrangements for retreats and travel and prepare appropriate claims. ... as necessary;; Records administrative actions and decisions on the files that the ... Prepares all purchase requisitions;; Arranges an all-staff ceremony for staff, ...

Late Effects of Polio: An Overview

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... Polio Wellness Retreats For Health Professionals The Late Effects of Polio: An Overview FRENCH | GERMAN | PORTUGUESE POLIOMYELITIS ( ... largest and most inclusive category is called Late Effects of Polio or Polio Sequelae and is defined ...

77 FR 56815 - Sunshine Act Notice

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2012-09-14

..., September 19, 2012, 10:00-11:30 a.m. PLACE: The Washington Hilton Hotel, 1919 Connecticut Avenue NW.... Summary of Retreat e. Momentum & Budget II. Consideration of Previous Meeting's Minutes III. CEO Report IV...

Scabies Treatment

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... returned and need retreatment. Incidentally, there is some controversy over the possible spread of scabies from clothing ... Email Print Share Donate Contact Us About Us Privacy Policy Terms of Use Editorial Policy This site ...

To What Extent Were Logistics Shortages Responsible for Patton's Culmination on the Meuse in 1944?

National Research Council Canada - National Science Library

Dye, Peter

1999-01-01

.... At this very moment, having hotly pursued the retreating German Army for more than 350 miles, Patton's mood changed from euphoria to frustration and then to despair as his armour ground to an abrupt...

Measurements of the asymmetric dynamic sheath around a pulse biased sphere immersed in flowing metal plasma

Science.gov (United States)

Wu, Hongchen; Anders, André

2008-08-01

A long-probe technique was utilized to record the expansion and retreat of the dynamic sheath around a spherical substrate immersed in pulsed cathode arc metal plasma. Positively biased, long cylindrical probes were placed on the side and downstream of a negatively pulsed biased stainless steel sphere of 1 in. (25.4 mm) diameter. The amplitude and width of the negative high voltage pulses (HVPs) were 2 kV, 5 kV, 10 kV, and 2 µs, 4 µs, 10 µs, respectively. The variation of the probe (electron) current during the HVP is a direct measure for the sheath expansion and retreat. Maximum sheath sizes were determined for the different parameters of the HVP. The expected rarefaction zone behind the biased sphere (wake) due to the fast plasma flow was clearly established and quantified.

Annually resolved ice core records of tropical climate variability over the past ~1800 years.

Science.gov (United States)

Thompson, L G; Mosley-Thompson, E; Davis, M E; Zagorodnov, V S; Howat, I M; Mikhalenko, V N; Lin, P-N

2013-05-24

Ice cores from low latitudes can provide a wealth of unique information about past climate in the tropics, but they are difficult to recover and few exist. Here, we report annually resolved ice core records from the Quelccaya ice cap (5670 meters above sea level) in Peru that extend back ~1800 years and provide a high-resolution record of climate variability there. Oxygen isotopic ratios (δ(18)O) are linked to sea surface temperatures in the tropical eastern Pacific, whereas concentrations of ammonium and nitrate document the dominant role played by the migration of the Intertropical Convergence Zone in the region of the tropical Andes. Quelccaya continues to retreat and thin. Radiocarbon dates on wetland plants exposed along its retreating margins indicate that it has not been smaller for at least six millennia.

ESTIMATION OF THE WANDA GLACIER (SOUTH SHETLANDS SEDIMENT EROSION RATE USING NUMERICAL MODELLING

Directory of Open Access Journals (Sweden)

Kátia Kellem Rosa

2013-09-01

Full Text Available Glacial sediment yield results from glacial erosion and is influenced by several factors including glacial retreat rate, ice flow velocity and thermal regime. This paper estimates the contemporary subglacial erosion rate and sediment yield of Wanda Glacier (King George Island, South Shetlands. This work also examines basal sediment evacuation mechanisms by runoff and glacial erosion processes during the subglacial transport. This is small temperate glacier that has seen retreating for the last decades. In this work, we examine basal sediment evacuation mechanisms by runoff and analyze glacial erosion processes occurring during subglacial transport. The glacial erosion rate at Wanda Glacier, estimated using a numerical model that consider sediment evacuated to outlet streams, ice flow velocity, ice thickness and glacier area, is 1.1 ton m yr-1.

Electromagnetically controlled measuring device for measuring injection quantities in a diesel injection pump volumetrically. Elektromagnetisch gesteuerte Messvorrichtung zur volumetrischen Messung von Einspritzmengen einer Dieseleinspritzpumpe

Energy Technology Data Exchange (ETDEWEB)

Hoffmann, K H; Mueller, M; Decker, R; Huber, G

1990-11-22

The invention concerns a measuring device for volumetric measurements of injection quantities of a diesel injection pump which injects its contents into a volumetric chamber controlled electromagnetically by a discharge valve and enclosed by a non-impact gas pressure loaded volumetric vessel and effects a retreating movement of the latter. The device is provided with an inductive path controller fitted with a differential pair of coils containing an axially movable ferromagnetic core. The path controller forms a part of a lifter rod connected to the volumetric vessel. It gives an opening signal to the discharge valve after each retreat of the volumetric vessel and a closing signal as soon as a defined height of suspension corresponding to the original position of the volumetric vessel after its return is reached.

Natural hazards, disasters and human kind: Whither ecosystem management?

Digital Repository Service at National Institute of Oceanography (India)

Mascarenhas, A.; Mudholkar, A.V.

in the way of powerful natural forces. Abandoning vulnerable geomorphic features, managed retreat, or safer setback with intervening forested landforms are feasible long-term options. The incalculable human misery that ultimately follows ia an ideal...