Interactive effects between nest microclimate and nest vegetation structure confirm microclimate thresholds for Lesser Prairie-Chicken nest survival

Science.gov (United States)

Grisham, Blake A.; Godar, Alixandra J.; Boal, Clint W.; Haukos, David A.

2016-01-01

The range of Lesser Prairie-Chickens (Tympanuchus pallidicinctus) spans 4 unique ecoregions along 2 distinct environmental gradients. The Sand Shinnery Oak Prairie ecoregion of the Southern High Plains of New Mexico and Texas is environmentally isolated, warmer, and more arid than the Short-Grass, Sand Sagebrush, and Mixed-Grass Prairie ecoregions in Colorado, Kansas, Oklahoma, and the northeast panhandle of Texas. Weather is known to influence Lesser Prairie-Chicken nest survival in the Sand Shinnery Oak Prairie ecoregion; regional variation may also influence nest microclimate and, ultimately, survival during incubation. To address this question, we placed data loggers adjacent to nests during incubation to quantify temperature and humidity distribution functions in 3 ecoregions. We developed a suite of a priori nest survival models that incorporated derived microclimate parameters and visual obstruction as covariates in Program MARK. We monitored 49 nests in Mixed-Grass, 22 nests in Sand Shinnery Oak, and 30 nests in Short-Grass ecoregions from 2010 to 2014. Our findings indicated that (1) the Sand Shinnery Oak Prairie ecoregion was hotter and drier during incubation than the Mixed- and Short-Grass ecoregions; (2) nest microclimate varied among years within ecoregions; (3) visual obstruction was positively associated with nest survival; but (4) daily nest survival probability decreased by 10% every half-hour when temperature was greater than 34°C and vapor pressure deficit was less than −23 mmHg during the day (about 0600–2100 hours). Our major finding confirmed microclimate thresholds for nest survival under natural conditions across the species' distribution, although Lesser Prairie-Chickens are more likely to experience microclimate conditions that result in nest failures in the Sand Shinnery Oak Prairie ecoregion. The species would benefit from identification of thermal landscapes and management actions that promote cooler, more humid nest microclimates.

Reviewing host proteins of Rhabdoviridae: possible leads for lesser studied viruses.

Science.gov (United States)

Guleria, A; Kiranmayi, M; Sreejith, R; Kumar, K; Sharma, S K; Gupta, S

2011-12-01

Rhabdoviridae, characterized by bullet-shaped viruses, is known for its diverse host range, which includes plants, arthropods, fishes and humans. Understanding the viral-host interactions of this family can prove beneficial in developing effective therapeutic strategies. The host proteins interacting with animal rhabdoviruses have been reviewed in this report. Several important host proteins commonly interacting with animal rhabdoviruses are being reported, some of which, interestingly, have molecular features, which can serve as potential antiviral targets. This review not only provides the generalized importance of the functions of animal rhabdovirus-associated host proteins for the first time but also compares them among the two most studied viruses, i.e. Rabies virus (RV) and Vesicular Stomatitis virus (VSV). The comparative data can be used for studying emerging viruses such as Chandipura virus (CHPV) and the lesser studied viruses such as Piry virus (PIRYV) and Isfahan virus (ISFV) of the Rhabdoviridae family.

Unique structure and optics of the lesser eyes of the box jellyfish Tripedalia cystophora

DEFF Research Database (Denmark)

Garm, A; Andersson, F; Nilsson, Dan-E

2008-01-01

mere light meters. The slit eyes, comprising four cell types, are complex and highly asymmetric. They also hold a lens-like structure, but its optical power is minute. Optical modeling suggests spatial resolution, but only in one plane. These unique and intriguing traits support strong peripheral......The visual system of box jellyfish comprises a total of 24 eyes. These are of four types and each probably has a special function. To investigate this hypothesis the morphology and optics of the lesser eyes, the pit and slit eyes, were examined. The pit eyes hold one cell type only and are probably...

Ancient xenocrystic zircon in young volcanic rocks of the southern Lesser Antilles island arc

Science.gov (United States)

Rojas-Agramonte, Yamirka; Williams, Ian S.; Arculus, Richard; Kröner, Alfred; García-Casco, Antonio; Lázaro, Concepción; Buhre, Stephan; Wong, Jean; Geng, Helen; Echeverría, Carlos Morales; Jeffries, Teresa; Xie, Hangqian; Mertz-Kraus, Regina

2017-10-01

The Lesser Antilles arc is one of the best global examples in which to examine the effects of the involvement of subducted sediment and crustal assimilation in the generation of arc crust. Most of the zircon recovered in our study of igneous and volcaniclastic rocks from Grenada and Carriacou (part of the Grenadines chain) is younger than 2 Ma. Within some late Paleogene to Neogene ( 34-0.2 Ma) lavas and volcaniclastic sediments however, there are Paleozoic to Paleoarchean ( 250-3469 Ma) xenocrysts, and Late Jurassic to Precambrian zircon ( 158-2667 Ma) are found in beach and river sands. The trace element characteristics of zircon clearly differentiate between different types of magmas generated in the southern Lesser Antilles through time. The zircon population from the younger arc (Miocene, 22-19 Ma, to Present) has minor negative Eu anomalies, well-defined positive Ce anomalies, and a marked enrichment in heavy rare earth elements (HREE), consistent with crystallization from very oxidized magmas in which Eu2 + was in low abundance. In contrast, zircon from the older arc (Eocene to mid-Oligocene, 30-28 Ma) has two different REE patterns: 1) slight enrichment in the light (L)REE, small to absent Ce anomalies, and negative Eu anomalies and 2) enriched High (H)REE, positive Ce anomalies and negative Eu anomalies (a similar pattern is observed in the xenocrystic zircon population). The combination of positive Ce and negative Eu anomalies in the zircon population of the older arc indicates crystallization from magmas that were variably, but considerably less oxidized than those of the younger arc. All the igneous zircon has positive εHf(t), reflecting derivation from a predominantly juvenile mantle source. However, the εHf(t) values vary significantly within samples, reflecting considerable Hf isotopic heterogeneity in the source. The presence of xenocrystic zircon in the southern Lesser Antilles is evidence for the assimilation of intra-arc crustal sediments and

Social-Ecological Thresholds in a Changing Boreal Landscape: Insights from Cree Knowledge of the Lesser Slave Lake Region of Alberta, Canada

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Brenda L. Parlee

2012-06-01

Full Text Available Drawing on the traditional ecological knowledge (TEK of the Lesser Slave Lake Cree, this paper shares understanding of how resource development has affected water, fish, forests, and wildlife as well as the well-being of Cree communities in the Lesser Slave Lake region of Alberta, Canada. In addition to descriptive observations of change, the narratives point to social-ecological thresholds or tipping points in the relationship of Cree harvesters to local lands and resources. Specifically, the study speaks to the echoing effects of ecological loss and degradation on traditional livelihood practices over the last 100 years highlighting the complexity of cumulative effects as well as the challenges of balancing resource development in the region with alternative land uses including those valued by Alberta's Aboriginal peoples.

Geodynamics and Stress State of the Earth's Crust in the Greater and Lesser Caucasus (Azerbaijan) collision region

Science.gov (United States)

Babayev, Gulam; Akhmedova, Elnare; Babayev, Elvin

2017-04-01

The current study researches the present-day stress state of the Earth's crust within the territory of Azerbaijan by using the database of the international research project "World Stress Map" (WSM). The present stress state was also assessed by exploring the effects of the contemporary topographic properties of Caucasus in three-dimensional frame. Aiming to explore the relative roles of regional tectonic conditions in the definition of stress state of Greater and Lesser Caucasus, stress distribution model was developed by the earthquake data (1998-2016) and by the standard techniques of stress field calculation. The results show that the stress orientations are influenced also by the combination of topography and crust thickness distribution even at very large depth. Stress data and earthquake focal mechanisms indicate that the stress state of the Earth's crust of the Greater and Lesser Caucasus is characterized by the compression predominantly oriented across the regional strike. The model results suggest that the Lesser Caucasus and Kur depression are rotating coherently, with little or no internal deformation in a counter-clockwise rotation located near the north-eastern corner of the Black Sea. Orientation of stress axes well consistent with earthquake focal mechanisms revealed that within Upper and Lower Crusts, earthquakes are predominantly thrust-faulting with a number of normal-faulting and some strike-slip faulting. The map of the focal mechanisms and stress distribution suggests that the research area is characterized by the thrust of horizontal compression trending north-north-east in the western part of the southern Caucasus. In the western part of Azerbaijan, the compression takes place between the Main Caucasus Fault and the Kur depression, which strikes south along the northern margin of the mountain range. In addition, a clear transition from the left-lateral strike slip to the predominantly right-lateral strike slip is observed in the southern of

A Longitudinal Analysis of the Effects of Socioeconomic Factors, Foreign Media, and Attitude toward Appearance on General and Central Adiposity in Chinese Adolescents.

Science.gov (United States)

Felicitas, Jamie Q; Tanenbaum, Hilary C; Li, Yawen; Chou, Chih-Ping; Palmer, Paula H; Spruijt-Metz, Donna; Reynolds, Kim D; Johnson, C Anderson; Xie, Bin

This paper explores the longitudinal effects of socioeconomic factors (i.e., parent education and family income level), foreign media, and attitude toward appearance on general and central adiposity among Chinese adolescents. A longitudinal analysis was performed using data from the China Seven Cities Study, a health promotion and smoking prevention study conducted in seven cities across Mainland China between 2002 and 2005. Participants included 5,020 middle and high school students and their parents. Explanatory variables included foreign media exposure, attitude toward appearance, parent education, and family income. Three-level, random-effect models were used to predict general adiposity (i.e., body mass index) and central adiposity (i.e., waist circumference). The Generalized Estimating Equation approach was utilized to determine the effect of explanatory variables on overweight status. Among girls, foreign media exposure was significantly negatively associated with general adiposity over time (β=-0.06, p=0.01 for middle school girls; β=-0.06, p=0.03 for high school girls). Attitude toward appearance was associated with lesser odds of being overweight, particularly among high school girls (OR=0.86, pgrade levels, family income was significantly negatively associated with central adiposity over time. Interventions addressing Chinese adolescent overweight/obesity should consider these factors as potential focus areas.

A study of the HEB longitudinal dynamics

International Nuclear Information System (INIS)

Larson, D.J.

1993-12-01

A study of the High Energy Booster (HEB) longitudinal dynamics is presented. Full derivations of ramp dependent longitudinal variables are given. The formulas assume that the input magnetic field and beam longitudinal emittance are known as a function of time, and that either the rf voltage or the rf bucket area are known as a function of time. Once these three inputs are specified, the formulas can be used to calculate values for all other longitudinal dynamics variables. The formulas have been incorporated into a single computer code named ELVIRA: Evaluation of Longitudinal Variables in Relativistic Accelerators. The ELVIRA code is documented here in detail. The ELVIRA code is used under two initial longitudinal emittance assumptions to plot ramp functions for the longitudinal dynamics design of the HEB as of May 5, 1992

Reforesting severely degraded grassland in the Lesser Himalaya of Central Nepal: effects on soil hydraulic conductivity and overland flow production

NARCIS (Netherlands)

Ghimire, C.P.; Bonell, M.; Bruijnzeel, L.A.; Coles, N.A.; Lubczynski, M.W.

2013-01-01

Severely degraded hillslopes in the Lesser Himalaya challenge local communities as a result of the frequent occurrence of overland flow and erosion during the rainy season and water shortages during the dry season. Reforestation is often perceived as an effective way of restoring predisturbance

The impact of warming and nutrients on algae production and microcystins in seston from the iconic lake lesser Prespa, Greece

NARCIS (Netherlands)

Maliaka, Valentini; Faassen, Elisabeth J.; Smolders, Alfons J.P.; Lürling, Miquel

2018-01-01

Lake Lesser Prespa and its adjacent pond, Vromolimni in Greece, is a shallow freshwater system and a highly protected area hosting an exceptional biodiversity. The occurrence of microcystins (MCs) producing cyanobacterial blooms in these waters during recent years can be harmful to the wildlife. We

Longitudinal relationship of parental hypertension with body mass index, blood pressure, and cardiovascular reactivity in children.

Science.gov (United States)

Li, Rongling; Alpert, Bruce S; Walker, Sammie S; Somes, Grant W

2007-05-01

To investigate whether parental hypertension (HTN) affects children's body mass index (BMI) and cardiovascular reactivity (CVR) over time. A longitudinal study of 315 students (black: 23 females, 19 males; white: 142 females, 131 males) was conducted in the public schools of Obion County, Tennessee, between 1987 and 1992. BMI and BMI z scores were calculated. The CVR task was a series of video games (taking approximately 10 minutes to play) given to the same students in their third-, fourth-, fifth-, seventh-, and eighth-grade years. CVR was defined as the change in blood pressure (delta_BP) or heart rate (delta_HR) between before playing and while playing the video game. Positive parental history of HTN (27.6%) was defined as at least 1 parent with HTN. Multivariable regression analyses were performed to estimate the effects of parental HTN on children's BMI and CVR over time. Children with parental HTN had significant higher BMI, BMI z score, and R_BP than did children without parental HTN (BMI: 21.6 vs 19.9, P = .001; BMI z score: 1.6 vs 1.1, P = .003; R_SBP: 112.6 vs 110.4 mm Hg, P = .01; R_DBP 62.7 vs 60.6 mm Hg, P = .003) after adjustment for covariates. Increased CVR was observed in children with parental HTN compared with children without parental HTN but was statistically significant only for SBP (delta_SBP: 17.2 vs 14.9 mm Hg; P = .01) after adjustment for covariates. Parental HTN independently predicted children's BMI, BMI z score, resting BP, and BP reactivity.

Inhibition of Colon Carcinoma Cell Migration Following Treatment with Purified Venom from Lesser Weever Fish (Trachinus Vipera

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Myriam Fezai

2017-04-01

Full Text Available Background: Injury by the sting of Lesser weever fish (Trachinus vipera may lead to severe pain, edema or tissue necrosis. Cellular effects of the venom are still incompletely understood. Previous observations revealed that purified Lesser weever fish venom (LWFV induces suicidal death of erythrocytes and HCT116 human colon carcinoma cells. The present study addressed the effect of the venom on colon carcinoma cell toxicity, shape and migration both in p53+/+ and/or p53-/- conditions. Methods: Cells were exposed to medium without or with 500 µg/ ml LWFV. Cell shape, cell area and circularity were visualized and quantified by fluorescence microscopy. Cell volume, granularity and cells toxicity were assessed via the apoptotic parameters dissipation of mitochondrial inner transmembrane potential, phosphatidylserine surface exposure and cell membrane permeabilization were measured utilizing flow cytometry. Cell migration was evaluated using wound healing assay and two-dimensional migration assay. Results: LWFV treatment was followed by a marked change of cell shape and size, significant decrease of cell area and circularity, significant impairment of cell migration, as well as induction of apoptosis after long exposition. Conclusions: LWFV exposure leads to cell shrinkage, increased granularity, apoptosis and impairment of cell migration, effects presumably contributing to LWFV-induced tissue injury.

Two cases of fatal necrosis of the lesser pelvis in patients treated with combined radiotherapy and hyperthermia for cervical carcinoma

NARCIS (Netherlands)

Wiggenraad, R.; Koning, C.; Westermann, C.; Jansen, C.; van der Zee, J.

2005-01-01

This study reports two cases of fatal necrosis of the lesser pelvis in patients with advanced cervical carcinoma, who had received combined radiotherapy and hyperthermia. The necrosis reached far from the high dose area, in one of the cases even outside the radiation portals. Both patients initially

Blood amyloid beta levels in healthy, mild cognitive impairment and Alzheimer's disease individuals: replication of diastolic blood pressure correlations and analysis of critical covariates.

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Agustín Ruiz

Full Text Available Plasma amyloid beta (Aβ levels are being investigated as potential biomarkers for Alzheimer's disease. In AB128 cross-sectional study, a number of medical relevant correlates of blood Aβ40 or Aβ42 were analyzed in 140 subjects (51 Alzheimer's disease patients, 53 healthy controls and 36 individuals diagnosed with mild cognitive impairment. We determined the association between multiple variables with Aβ40 and Aβ42 levels measured in three different blood compartments called i Aβ directly accessible (DA in the plasma, ii Aβ recovered from the plasma matrix (RP after diluting the plasma sample in a formulated buffer, and iii associated with the remaining cellular pellet (CP. We confirmed that diastolic blood pressure (DBP is consistently correlated with blood DA Aβ40 levels (r=-0.19, P=0.032. These results were consistent in the three phenotypic groups studied. Importantly, the observation resisted covariation with age, gender or creatinine levels. Observed effect size and direction of Aβ40 levels/DBP correlation are in accordance with previous reports. Of note, DA Aβ40 and the RP Aβ40 were also strongly associated with creatinine levels (r=0.599, P<<0.001 and to a lesser extent to urea, age, hematocrit, uric acid and homocysteine (p<0.001. DBP and the rest of statistical significant correlates identified should be considered as potential confounder factors in studies investigating blood Aβ levels as potential AD biomarker. Remarkably, the factors affecting Aβ levels in plasma (DA, RP and blood cell compartments (CP seem completely different.

Melaleuca alternifolia Essential Oil against the Lesser Mealworm (Alphitobius diaperinus and Its Possible Effect on the Soil Fauna

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A Volpato

2016-03-01

Full Text Available ABSTRACT The aim of this study was to evaluate the in vitro bioactivity of tea tree (Melaleuca alternifolia essential oil against larvae and adult forms of lesser mealworms (Alphitobius diaperinus and its influence on the soil fauna. Tests were performed in triplicate using pure tea tree oil (TTO; 1, 5, 10, 25, 50, and 100%, TTO nanoparticles (1, 3, and 7.5%, or terpinen-4-ol, the main compound of the tea tree oil, at the same concentrations of TTO. Larvae and adult mortality occurred at concentrations up to 10 and 50% of TTO, respectively. No larvicidal or insecticidal effect of TTO nanoparticles was observed. Terpinen-4-ol showed insecticidal and larvicidal effect at concentrations higher than 25%. The evaluation of TTO effect on soil organisms was performed by standard ecotoxicological tests (ISO with the springtail species Folsomia candida. Only TTO was used for ecotoxicological tests in doses of 1, 5, 10, 25, 50, and 100 mg kg-1 of soil. TTO had no negative effects on F. candida survival or reproduction. Therefore, it was concluded that M. alternifolia oil may be a new alternative for control of the lesser mealworm.

GPS tracking data of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast.

Science.gov (United States)

Stienen, Eric W M; Desmet, Peter; Aelterman, Bart; Courtens, Wouter; Feys, Simon; Vanermen, Nicolas; Verstraete, Hilbran; de Walle, Marc Van; Deneudt, Klaas; Hernandez, Francisco; Houthoofdt, Robin; Vanhoorne, Bart; Bouten, Willem; Buijs, Roland-Jan; Kavelaars, Marwa M; Müller, Wendt; Herman, David; Matheve, Hans; Sotillo, Alejandro; Lens, Luc

2016-01-01

In this data paper, Bird tracking - GPS tracking of Lesser Black-backed Gulls and Herring Gulls breeding at the southern North Sea coast is described, a species occurrence dataset published by the Research Institute for Nature and Forest (INBO). The dataset (version 5.5) contains close to 2.5 million occurrences, recorded by 101 GPS trackers mounted on 75 Lesser Black-backed Gulls and 26 Herring Gulls breeding at the Belgian and Dutch coast. The trackers were developed by the University of Amsterdam Bird Tracking System (UvA-BiTS, http://www.uva-bits.nl). These automatically record and transmit bird movements, which allows us and others to study their habitat use and migration behaviour in great detail. Our bird tracking network is operational since 2013. It is funded for LifeWatch by the Hercules Foundation and maintained in collaboration with UvA-BiTS and the Flanders Marine Institute (VLIZ). The recorded data are periodically released in bulk as open data (http://dataset.inbo.be/bird-tracking-gull-occurrences), and are also accessible through CartoDB and the Global Biodiversity Information Facility (GBIF).

New Geochronology and Radiometric Age Dates Improve the Definition and Continuity of Accreted Tectonic Terranes of Northern Venezuela and the Lesser Antilles

Science.gov (United States)

Baquero, M.; Mann, P.; Audemard, F. A.

2017-12-01

We use new and compiled geochronology and radiometric dates from the area of Venezuela to Tobago to define the following crustal provinces: 1) Guyana shield forms a sub-circular area of Pan-African rocks against which all younger terranes have collided and partially assumed its rounded shape: ages for the Guyana Shield range from >3.4 Ga to 1.8 Ga; 2) accreted Paleozoic rocks form a sub-circular, largely buried province that surround the Guiana Shield to the north and west; the El Pilar strike-slip fault forms the abrupt, northern limit of the Precambrian-Paleozoic craton in Venezuela characterized by crustal thicknesses of 40-50 km; 3) the Early to Late Cretaceous Great Arc of the Caribbean forms a continuous basement high that can be traced from northern Colombia, through the ABC Islands to La Blanquilla Island, and north along the Aves Ridge to the Greater Antilles; ages of the GAC generally are in the range of Late Cretaceous to early Eocene and have geochemistry consistent with intra-oceanic island arcs or oceanic plateau rocks with the exception of La Orchila Island with a Paleozoic intrusive age; the GAC collided from west to east with the passive margin of South America from Paleocene in western Venezuela to Plio-Pleistocene in the Trinidad area and marks the west to east passage of the Caribbean plate past the South American plate; 4) a post-GAC rifting event affected the GAC-South America suture from late Eocene to middle Miocene time in the Falcón Basin of western Venezuela with ages on intrusive and volcanic from 34 to 15.4 Ma; these ages are coeval with intrusive ages from the southernmost Lesser Antilles on Los Frailes and Los Testigos Islands and range from 35.7±2.6 to 36.4±0.5 Ma; the age of the intervening basin, the Bonaire basin, is poorly known but may be coeval with the Oligocene-Miocene extension that extended the suture zone in western Venezuela and extended the Lesser Antilles arc in early Middle Miocene time to form the Lesser Antilles

On Longitudinal Spectral Coherence

DEFF Research Database (Denmark)

Kristensen, Leif

1979-01-01

It is demonstrated that the longitudinal spectral coherence differs significantly from the transversal spectral coherence in its dependence on displacement and frequency. An expression for the longitudinal coherence is derived and it is shown how the scale of turbulence, the displacement between ...... observation sites and the turbulence intensity influence the results. The limitations of the theory are discussed....

Main copper-porphyry systems of the Lesser Caucasus

International Nuclear Information System (INIS)

Melkonyan, R.L.; Tayan, P.N.; Goukassyan, R.Kh.; Hovakimyan, S.E.; Moritz, R.; Selbi, D.

2013-01-01

Two belts of porphyry-copper systems were identified the Late Jurassic Early Cretaceous Somkheto-Karabakh (S-K) island-arc belt within the same name terrain of the southern termination of the Eurasian Plate stretching for 230 km (the tonalitic model) and the Early Miocene Tsaghkounk-Zanghezour (Ts-Z) post-collision belt (Tz-Z) within the same name terrain of the northern margin of the Gondwana, stretching over 280 km (the monzonite-granodiorite model). The formation of the S-K and Ts-Z belts had proceeded in pulses and spanned intervals of 12 million years and 24 million years, respectively. The Rb-Sr isochrones and TIMS U-Pb estimations of the age of zircons from the Meghri pluton ( 1,500 km 2 ), the largest one in the Lesser Caucasus, it appeared possible to establish the three stages of its formation: the Late Eocene, Early Oligocene, and Early Miocene, each accompanied by development of deposits having similar ages. The PC deposits of the S-K and Ts-Z belts have distinct differences of age, geodynamic regime of formation, specificity of mineral composition, sources of water and sulfur of hydrothermal solutions, and formation models. The single, discrete Armenian-Iranian belt of PC deposits was identified; it has a Late Eocene-Middle Miocene age and a length of about 2,000 km, being related with intrusive complexes of the monzonite-granite-granodiorite series, the activity of which had been manifesting itself over 32 million years. This belt, including giant-deposits such as Kajaran and Sar-Cheshmeh, was identified as the special Armenian-Iranian PC province

Longitudinal Research with Latent Variables

CERN Document Server

van Montfort, Kees; Satorra, Albert

2010-01-01

This book combines longitudinal research and latent variable research, i.e. it explains how longitudinal studies with objectives formulated in terms of latent variables should be carried out, with an emphasis on detailing how the methods are applied. Because longitudinal research with latent variables currently utilizes different approaches with different histories, different types of research questions, and different computer programs to perform the analysis, the book is divided into nine chapters. Starting from some background information about the specific approach, short history and the ma

Longitudinal joint specifications and performance.

Science.gov (United States)

2012-08-01

Deterioration of longitudinal joints is widely recognized as one of the major factors contributing to failure of asphalt pavements. Finding : ways to improve the durability of longitudinal joints will lead to improved service lives and lower life cyc...

Evaluation of longitudinal loading of tank trains during motion in longitudinal changes of gradient

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S.V. Myamlin

2013-06-01

Full Text Available Purpose. To research the tank train longitudinal loading during motion by track sections with changes of gradient. The trains of different length that consist of bogie tank wagons should be examined. Influence of cargo type on longitudinal loading of train during motion in concave section of track should be evaluated. Methodology. The level of the largest longitudinal forces was estimated by mathematical simulation. It was assumed that change of gradient is formed by two grades with baffle platforms, length 50 meters, so that the algebraic difference of limiting grades vary from 10‰ to 40‰, pitch 10‰. The initial speeds were 40, 60, 80, 100, 120 km/h. For evaluation of the longitudinal loading the regulating braking and motion "by coasting" was considered. For evaluation of buffing loads the entry to the concave gradient change of expanded train is considered, and in order to determine the quasi-static forces the compressed train is considered. Findings. As a result of calculations the dependencies of maximal longitudinal forces in the trains on the cargo type, the algebraic difference of the grades, the number of tank wagons, the initial speed, motion modes, and initial gaps condition in the train were obtained. Originality. The longitudinal loading of freight cars of different length formed by the similar bogie tank wagons with one locomotive was obtained. The locomotive is placed in the train head during motion in concave track sections with various algebraic difference of the grades "on coasting" and during the regulating braking mode. The obtained results can be used for parameters standardization of profile elevation of the track. Practical value. The obtained results show that during operation of tank trains on track sections of complex breakage the most dangerous is regulating braking of preliminary compressed trains during entering on concave parts of track. Level of the greatest buffing and quasi-static longitudinal forces is

Application of Persistent Scatterer Interferometry (PSI) in monitoring slope movements in Nainital, Uttarakhand Lesser Himalaya, India

Science.gov (United States)

Yhokha, Akano; Goswami, Pradeep K.; Chang, Chung-Pai; Yen, Jiun-Yee; Ching, Kuo-En; Aruche, K. Manini

2018-02-01

Orogenic movements and sub-tropical climate have rendered the slopes of the Himalayan region intensely deformed and weathered. As a result, the incidences of slope failure are quite common all along the Himalayan region. The Lesser Himalayan terrane is particularly vulnerable to mass-movements owing to geological fragility, and many parts of it are bearing a high-risk of associated disaster owing to the high population density. An important step towards mitigation of such disasters is the monitoring of slope movement. Towards this, the Persistent Scatterer Interferometry (PSI) technique can be applied. In the present study, the PSI technique is employed in Lesser Himalayan town of Nainital in Uttarakhand state of India to decipher and monitor slope movements. A total of 15 multi-date ENVISAT ASAR satellite images, acquired during August 2008 to August 2010 period, were subjected to PSI, which revealed a continuous creep movement along the hillslopes located towards the eastern side of the Nainital lake. The higher reaches of the hill seem to be experiencing accelerated creep of {˜ }21 mm/year, which decreases downslope to {˜ }5 mm/year. Based on spatial pattern of varying PSI Mean LOS Velocity (MLV) values, high (H), moderate (M), low (L) and very low (S) creeping zones have been delineated in the hillslopes. Given the long history of mass movements and continuously increasing anthropogenic activities in Nainital, these results call for immediate measures to avert any future disaster in the town.

Testing competing hypotheses for chronology and intensity of lesser scaup molt during winter and spring migration

Science.gov (United States)

Anteau, Michael J.; Anteau, Andrea C.E.; Afton, Alan D.

2011-01-01

We examined chronology and intensity of molt and their relationships to nutrient reserves (lipid and protein) of Lesser Scaup (Aythya affinisK/i>) to test predictions of two competing hypotheses. The "staggered cost" hypothesis states that contour-feather molt is nutritionally costly and should not occur during nutritionally costly periods of the annual cycle unless adequate nutrients are available. The "breeding plumage" hypothesis states that prealternate molt must be complete prior to nesting, regardless of nutrient availability. Males and females were completing prebasic molt during winter (Louisiana) and had similar molt intensities. Females underwent prealternate molt during spring migration (Illinois and Minnesota) and prebreeding (Manitoba) periods; 53% and 93% of females were in moderate to heavy molt in Minnesota and Manitoba, respectively, despite experiencing other substantial nutritional costs. Intensity of prealternate molt was not correlated with lipid reserves even though females, on average, were nutritionally stressed. Molt intensity was not negatively correlated with protein reserves at any location. Chronology and intensity of prealternate molt varied little and were not temporally staggered from other nutritionally costly events. Prealternate molt did not influence nutrient reserves, and nutrient reserves likely were not the ultimate factor influencing chronology or intensity of prealternate molt of females. We surmise that nutrients required for prealternate molt come from exogenous sources and that the "staggered cost" hypothesis does not explain chronology of prealternate molt in female Lesser Scaup; rather, it appears that molt must be complete prior to nesting, consistent with the "breeding plumage" hypothesis.

First amplification of Eimeria hessei DNA from the lesser horseshoe bat (Rhinolophus hipposideros) and its phylogenetic relationships with Eimeria species from other bats and rodents.

Science.gov (United States)

Afonso, Eve; Baurand, Pierre-Emmanuel; Tournant, Pierline; Capelli, Nicolas

2014-04-01

Although coccidian parasites of the genus Eimeria are among the best-documented parasites in bats, few Eimeria species found in bats have been characterised using molecular tools, and none of the characterised species are found in European countries. Phylogenetic relationships of Eimeria species that parasitise bats and rodents can be related to the morphology of oocysts, independently from host range, suggesting that these species are derived from common ancestors. In the present study, we isolated a partial sequence of the Eimeria hessei 18S rRNA gene from the lesser horseshoe bat (Rhinolophus hipposideros), a European bat species. Droppings from lesser horseshoe bats were collected from 11 maternity roosts located in France that were positive for the presence of the parasite. Through morphological characterisation, the oocysts detected in the lesser horseshoe bat droppings were confirmed to be E. hessei. The unique E. hessei sequence obtained through molecular analysis belonged to a clade that includes both rodent and bat Eimeria species. However, the E. hessei oocysts isolated from the bat droppings did not show morphological similarities to rodent Eimeria species. Copyright © 2014 Elsevier Inc. All rights reserved.

Reproductive biology of lesser spotted dogfish Scyliorhinus canicula (L., 1758 in the Cantabrian Sea

Directory of Open Access Journals (Sweden)

C. Rodríguez-Cabello

1998-09-01

Full Text Available This paper examines sexual maturity of the female lesser spotted dogfish Scyliorhinus canicula (L., 1758 in the Cantabrian Sea (north of Spain. Analyses made using data collected from commercial trawlers during 1994 and 1995 showed that females reach sexual maturity at a length of 54.2 cm, and the mean egg-laying size is 56.4 ± 0.94 cm. At least one in six adult female dogfish carried egg-capsules during the study period. Sex-ratio by depth strata indicates a larger proportion of females in deeper waters. Mature and spawning females were found at depths ranging from 100 m to more than 400 m, with their proportion being larger in the deeper strata.

Seismic tomography of Basse-Terre volcanic island, Guadeloupe, Lesser Antilles, using earthquake travel times and noise correlations

Science.gov (United States)

Barnoud, Anne; Coutant, Olivier; Bouligand, Claire; Massin, Frédérick; Stehly, Laurent

2015-04-01

We image the volcanic island of Basse-Terre, Guadeloupe, Lesser Antilles, using both earthquake travel times and noise correlations. (1) A new earthquake catalog was recently compiled for the Lesser Antilles by the CDSA/OVSG/IPGP (Massin et al., EGU General Assembly 2014) and allows us to perform classical travel time tomography to obtain smooth 3D body wave velocity models. The geometrical configuration of the volcanic arc controls the resolution of the model in our zone of interest. (2) Surface wave tomography using noise correlations was successfully applied to volcanoes (Brenguier et al., Geophys. Res. Lett. 2007). We use seismic noise recorded at 16 broad-band stations and 9 short-period stations from Basse-Terre over a period of six years (2007-2012). For each station pair, we extract a dispersion curve from the noise correlation to get surface wave velocity models. The inversion of the dispersion curves produces a 3D S-wave velocity model of the island. The spatial distribution of seismic stations accross the island is highly heterogeneous, leading to higher resolution near the dome of the Soufrière of Guadeloupe volcano. Resulting velocity models are compared with densities obtained by 3D inversion of gravimetric data (Barnoud et al., AGU Fall Meeting 2013). Further work should include simultaneous inversion of seismic and gravimetric datasets to overcome resolution limitations.

Longitudinal Space Charge in the SPS

CERN Document Server

Lasheen, Alexandre

2016-01-01

Longitudinal instabilities due to the SPS beam coupling impedance are a major issue for future projects and it is essential to have an accurate SPS impedance model to study them. The longitudinal space charge effect can be modelled by a pure reactive impedance and should also be included in simulations as it may have an impact at low energy. In this Note, the effect of the longitudinal space charge in the SPS is evaluated by taking into account the variation of the transverse beam size and vacuum chamber geometry along the ring. Scaling laws are used to investigate what are the most important parameters for the evaluation of the longitudinal space charge impedance.

Cross-Sectional Analysis of Longitudinal Mediation Processes.

Science.gov (United States)

O'Laughlin, Kristine D; Martin, Monica J; Ferrer, Emilio

2018-01-01

Statistical mediation analysis can help to identify and explain the mechanisms behind psychological processes. Examining a set of variables for mediation effects is a ubiquitous process in the social sciences literature; however, despite evidence suggesting that cross-sectional data can misrepresent the mediation of longitudinal processes, cross-sectional analyses continue to be used in this manner. Alternative longitudinal mediation models, including those rooted in a structural equation modeling framework (cross-lagged panel, latent growth curve, and latent difference score models) are currently available and may provide a better representation of mediation processes for longitudinal data. The purpose of this paper is twofold: first, we provide a comparison of cross-sectional and longitudinal mediation models; second, we advocate using models to evaluate mediation effects that capture the temporal sequence of the process under study. Two separate empirical examples are presented to illustrate differences in the conclusions drawn from cross-sectional and longitudinal mediation analyses. Findings from these examples yielded substantial differences in interpretations between the cross-sectional and longitudinal mediation models considered here. Based on these observations, researchers should use caution when attempting to use cross-sectional data in place of longitudinal data for mediation analyses.

Lesser Himalayan sequences in Eastern Himalaya and their deformation: Implications for Paleoproterozoic tectonic activity along the northern margin of India

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Dilip Saha

2013-05-01

Full Text Available Substantial part of the northern margin of Indian plate is subducted beneath the Eurasian plate during the Caenozoic Himalayan orogeny, obscuring older tectonic events in the Lesser Himalaya known to host Proterozoic sedimentary successions and granitic bodies. Tectonostratigraphic units of the Proterozoic Lesser Himalayan sequence (LHS of Eastern Himalaya, namely the Daling Group in Sikkim and the Bomdila Group in Arunachal Pradesh, provide clues to the nature and extent of Proterozoic passive margin sedimentation, their involvement in pre-Himalayan orogeny and implications for supercontinent reconstruction. The Daling Group, consisting of flaggy quartzite, meta-greywacke and metapelite with minor mafic dyke and sill, and the overlying Buxa Formation with stromatolitic carbonate-quartzite-slate, represent shallow marine, passive margin platformal association. Similar lithostratigraphy and broad depositional framework, and available geochronological data from intrusive granites in Eastern Himalaya indicate strikewise continuity of a shallow marine Paleoproterozoic platformal sequence up to Arunachal Pradesh through Bhutan. Multiple fold sets and tectonic foliations in LHS formed during partial or complete closure of the sea/ocean along the northern margin of Paleoproterozoic India. Such deformation fabrics are absent in the upper Palaeozoic–Mesozoic Gondwana formations in the Lesser Himalaya of Darjeeling-Sikkim indicating influence of older orogeny. Kinematic analysis based on microstructure, and garnet composition suggest Paleoproterozoic deformation and metamorphism of LHS to be distinct from those associated with the foreland propagating thrust systems of the Caenozoic Himalayan collisional belt. Two possibilities are argued here: (1 the low greenschist facies domain in the LHS enveloped the amphibolite to granulite facies domains, which were later tectonically severed; (2 the older deformation and metamorphism relate to a Pacific type

Canine distemper virus infection in a lesser grison (Galictis cuja: first report and virus phylogeny

Directory of Open Access Journals (Sweden)

Jane Megid

2013-02-01

Full Text Available Infectious diseases in wild animals have been increasing as a result of their habitat alterations and closer contact with domestic animals. Canine distemper virus (CDV has been reported in several species of wild carnivores, presenting a threat to wildlife conservation. We described the first case of canine distemper virus infection in lesser grison (Galictis cuja. A free-ranging individual, with no visible clinical sigs, presented sudden death after one day in captivity. Molecular diagnosis for CDV infection was performed using whole blood collected by postmortem intracardiac puncture, which resulted positive. The virus phylogeny indicated that domestic dogs were the probable source of infection.

Radiological evaluation of subjects submitted to vagotomy, antrectomy and gastroduodenal anastomosis at the lesser curvature in chlorydropeptic ulceration

International Nuclear Information System (INIS)

Silva, A.L.; Petroianu, A.; Ferreira, C.S.

1988-01-01

This work shows a radiologic study of stomachs operated for chlorydropeptic ulceration by the surgical technique of: vagotomy, antrectomy and gastroduodenal anastomosis at the lesser curvature. Our objective was to observe the gastric morphology and motility turned to its emptying. The results suggested good perspectives, mainly, in the late post-operative. The operated stomachs get a similar morphology with the normal one and its emptying, at first, slow, tended to normalize. (author) [pt

A meta-analysis of lesser prairie-chicken nesting and brood-rearing habitats: implications for habitat management

Science.gov (United States)

Hagen, Christian A.; Grisham, Blake A.; Boal, Clint W.; Haukos, David A.

2013-01-01

The distribution and range of lesser prairie-chicken (Tympanuchus pallidicinctus) has been reduced by >90% since European settlement of the Great Plains of North America. Currently, lesser prairie-chickens occupy 3 general vegetation communities: sand sagebrush (Artemisia filifolia), sand shinnery oak (Quercus havardii), and mixed-grass prairies juxtaposed with Conservation Reserve Program grasslands. As a candidate for protection under the Endangered Species Act, there is a need for a synthesis that characterizes habitat structure rangewide. Thus, we conducted a meta-analysis of vegetation characteristics at nest sites and brood habitats to determine whether there was an overall effect (Hedges' d) of habitat selection and to estimate average (95% CI) habitat characteristics at use sites. We estimated effect sizes (di) from the difference between use (nests and brood sites) and random sampling sites for each study (n = 14), and derived an overall effect size (d++). There was a general effect for habitat selection as evidenced by low levels of variation in effect sizes across studies and regions. There was a small to medium effect (d++) = 0.20-0.82) of selection for greater vertical structure (visual obstruction) by nesting females in both vegetation communities, and selection against bare ground (d++ = 0.20-0.58). Females with broods exhibited less selectivity for habitat components except for vertical structure. The variation of d++ was greater during nesting than brooding periods, signifying a seasonal shift in habitat use, and perhaps a greater range of tolerance for brood-rearing habitat. The overall estimates of vegetation cover were consistent with those provided in management guidelines for the species.

Testing competing hypotheses for chronology and intensity of lesser scaup molt during winter and spring migration

Science.gov (United States)

Anteau, M.J.; Anteau, A.C.E.; Afton, A.D.

2011-01-01

We examined chronology and intensity of molt and their relationships to nutrient reserves (lipid and protein) of Lesser Scaup (Aythya affinis) to test predictions of two competing hypotheses. The "staggered cost" hypothesis states that contour-feather molt is nutritionally costly and should not occur during nutritionally costly periods of the annual cycle unless adequate nutrients are available. The "breeding plumage" hypothesis states that prealternate molt must be complete prior to nesting, regardless of nutrient availability. Males and females were completing prebasic molt during winter (Louisiana) and had similar molt intensities. Females underwent prealternate molt during spring migration (Illinois and Minnesota) and prebreeding (Manitoba) periods; 53% and 93% of females were in moderate to heavy molt in Minnesota and Manitoba, respectively, despite experiencing other substantial nutritional costs. Intensity of prealternate molt was not correlated with lipid reserves even though females, on average, were nutritionally stressed. Molt intensity was not negatively correlated with protein reserves at any location. Chronology and intensity of prealternate molt varied little and were not temporally staggered from other nutritionally costly events. Prealternate molt did not influence nutrient reserves, and nutrient reserves likely were not the ultimate factor influencing chronology or intensity of prealternate molt of females. We surmise that nutrients required for prealternate molt come from exogenous sources and that the "staggered cost" hypothesis does not explain chronology of prealternate molt in female Lesser Scaup; rather, it appears that molt must be complete prior to nesting, consistent with the "breeding plumage" hypothesis. ?? The Cooper Ornithological Society 2011.

Tectonic implications of U-Pb (zircon) Geochronology of Chor Granitoids of the Lesser Himalaya, Himachal Pradesh, NW Himalaya

Science.gov (United States)

Singh, P.; Bhakuni, S. S.

2017-12-01

Granitoids of various ages ranging from Proterozoic to Tertiary occur throughout the Himalayan fold-thrust belt. The occurrence of the Neoproterozoic granitoids are very less in the Himalayan orogen. One of the best example of Neoproterozoic granitoids is Chor granitoids, which are the intrusive granite bodies in the Paleoproterozoic of the Lesser Himalayan Crystallines of the Jutogh Group. In the central part these granites are non-foliated homogeneous that are porphyritic and peraluminous in nature (Singh et al., 2002; Bhargava et al., 2014, 2016), whereas in the peripheral part these are foliated showing south directed shear sense of movement. In this work we present the U-Pb (zircon) geochronology of two different granites samples of the Chor granitoids of Himachal Pradesh, NW Himalaya. The Jutogh Group of rocks is thrust over the Lesser Himalayan Sequence along the Jutogh Thrust or MCT. The geochronology of the Chor Granitoids and Lesser Himalayan Crystallines and their relationship with each other, including with the Indian shield are sparsely obscure. U-Pb zircon geochrnological age populations from these granitoids yield ages between 780 and 980 Ma. One sample gives the prominent age spectra for 206Pb/238U with weighted mean age of 908.3 ± 6.7 Ma (2σ) MSWD = 2.4 (n = 18). Similarly another sample gives the age of crystallization with weight mean age of 917 ± 17 Ma (2σ) MSWD = 3 (n = 11) and Th/U ratios of both samples are >0.1, indicating their magmatic origin. As a result of ductile shearing of granites along the MCT during the Cenozoic Himalayan Orogeny, the age has reduced to 780 Ma. The Neoproterozoic age of Chor granite matches with the Neoproterozoic detrital zircon age (800 to 1000 Ma by Parrish and Hodges 1996, Decelles et al., 2000) of the HHC. On the basis of U-Pb (zircon) geochronological ages, it is revealed that the source of zircons of the Chor granite and HHC rocks was the northern margin of the Pan-African orogen. The Chor granitoids was

Longitudinal dynamics of laser-cooled fast ion beams

DEFF Research Database (Denmark)

Weidemüller, M.; Eike, B.; Eisenbarth, U.

1999-01-01

We present recent results of our experiments on laser cooling of fast stored ion beams at the Heidelberg Test Storage Ring. The longitudinal motion of the ions is directly cooled by the light pressure force, whereas efficient transverse cooling is obtained indirectly by longitudinal-transverse co......We present recent results of our experiments on laser cooling of fast stored ion beams at the Heidelberg Test Storage Ring. The longitudinal motion of the ions is directly cooled by the light pressure force, whereas efficient transverse cooling is obtained indirectly by longitudinal....... When applying laser cooling in square-well buckets over long time intervals, hard Coulomb collisions suddenly disappear and the longitudinal temperature drops by about a factor of three. The observed longitudinal behaviour of the beam shows strong resemblance with the transition to an Coulomb...

Longitudinal beam dynamics at transition crossing

Energy Technology Data Exchange (ETDEWEB)

Bogacz, S.A.

1991-11-01

A brief outline of the longitudinal single particle dynamics at transition is presented in terms of phase-space mappings. Simple quantitative prediction about the phase-space dilution is made. More realistic simulation (ESME) of the transition crossing is carried out (including various collective and single particle effects contributing to the longitudinal emittance blow up). The simulation takes into account the longitudinal space-charge force (bunch length oscillation), the transverse space-charge (the Umstaetter effect) and finally the dispersion of the momentum compaction factor (the Johnsen effect). As a result of this simulation one can separate relative strengths of the above mechanisms and study their individual effects on the longitudinal phase-space evolution, especially filamentation of the bunch and formation of a galaxy-like'' pattern. 7 refs., 2 figs.

Loading Conditions and Longitudinal Strength

DEFF Research Database (Denmark)

Sørensen, Herman

1995-01-01

Methods for the calculation of the lightweight of the ship.Loading conditions satisfying draught, trim and intact stability requirements and analysis of the corresponding stillwater longitudinal strength.......Methods for the calculation of the lightweight of the ship.Loading conditions satisfying draught, trim and intact stability requirements and analysis of the corresponding stillwater longitudinal strength....

Longitudinal trajectories of subjective care stressors: the role of personal, dyadic, and family resources.

Science.gov (United States)

Bangerter, Lauren R; Liu, Yin; Zarit, Steven H

2017-11-24

Stressors are critical to the caregiver stress process, yet little work has examined resources that contribute to longitudinal changes in subjective stressors. The present study examines a variety of factors that contribute to changes in subjective stressors across time. Dementia caregivers (N = 153) completed an in-person interview and eight daily telephone interviews at baseline, and follow up interviews at 6 and 12 months. Growth curve analyses examine how care- and non-care stressors, respite, dyadic relationship quality, family support/conflict and care transitions (e.g. nursing home placement) are associated with changes in role overload and role captivity across 12 months. Caregivers who transitioned out of their role had higher overload and captivity at baseline. Among caregivers who transitioned out of caregiving, higher captivity at baseline was associated with declines in captivity and overload; more non-care stressors at baseline was linked to increased captivity and greater overload across time. Adult day service use and family support were associated with lesser captivity over time; taking more breaks from caregiving was linked to lower overload. Higher dyadic relationship quality was associated with lower captivity and overload. Findings contribute to caregiver intervention efforts by highlighting important resources associated with subjective stressors across time.

Long-distance multistep sediment transfer at convergent plate margins (Barbados, Lesser Antilles)

Science.gov (United States)

Limonta, Mara; Garzanti, Eduardo; Resentini, Alberto; Andò, Sergio; Boni, Maria; Bechstädt, Thilo

2015-04-01

We present a regional provenance study of the compositional variability and long distance multicyclic transport of terrigenous sediments along the convergent and transform plate boundaries of Central America, from the northern termination of the Andes to the Lesser Antilles arc-trench system. We focus on high-resolution bulk-petrography and heavy-mineral analyses of modern beach and fluvial sediments and Cenozoic sandstones of Barbados island, one of the places in the world where an active accretionary prism is subaerially exposed (Speed et al., 2012). The main source of siliciclastic sediment in the Barbados accretionary prism is off-scraped quartzose to feldspatho-litho-quartzose metasedimentaclastic turbidites, ultimately supplied from South America chiefly via the Orinoco fluvio-deltaic system. Modern sand on Barbados island is either quartzose with depleted heavy-mineral suites recycled from Cenozoic turbidites and including epidote, zircon, tourmaline, andalusite, garnet, staurolite and chloritoid, or calcareous and derived from Pleistocene coral reefs. The ubiquitous occurrence of clinopyroxene and hypersthene, associated with green-brown kaersutitic hornblende in the north or olivine in the south, points to reworking of ash-fall tephra erupted from andesitic (St. Lucia) and basaltic (St. Vincent) volcanic centers in the Lesser Antilles arc transported by the prevailing anti-trade winds in the upper troposphere. Modern sediments on Barbados island and those shed by other accretionary prisms such as the Indo- Burman Ranges and Andaman-Nicobar Ridge (Garzanti et al., 2013) define the distinctive mineralogical signature of Subduction Complex Provenance, which is invariably composite. Detritus recycled dominantly from accreted turbidites and oceanic mudrocks is mixed in various proportions with detritus from the adjacent volcanic arc or carbonate reefs widely developed at tropical latitudes. Ophiolitic detritus may be locally prominent. Quantitative provenance

Sources of measurement variation in blood pressure in large-scale epidemiological surveys with follow-up

DEFF Research Database (Denmark)

Andersen, Ulla Overgaard; Henriksen, Jens H; Jensen, Gorm

2002-01-01

The Copenhagen City Heart Study (CCHS) is a longitudinal epidemiological study of 19698 subjects followed up since 1976. Variation in blood pressure (BP) measurement in the first three CCHS surveys is evaluated by assessing two components, systematic variation and random variation [daytime...... min rest, with the cuff around the non-dominating arm, in accordance with recommended guidelines. The participation rate fell from 74% in survey 1 to 63% in survey 3. Significant non-response bias with respect to BP values was not found. No daytime variability was noted either in systolic (SBP...... and plasma cholesterol. SBP was 5-10 mmHg higher in diabetics (p = 0.000-0.04) than in age- and sex-matched non-diabetics. DBP did not differ between the two groups. Smokers from the age of 50 years had a 2-4 mmHg lower SBP (p = 0.000-0.01) and 1-3 mmHg lower DBP (p = 0.000-0.005) than had non...

Plastics derived endocrine disruptors (BPA, DEHP and DBP induce epigenetic transgenerational inheritance of obesity, reproductive disease and sperm epimutations.

Directory of Open Access Journals (Sweden)

Mohan Manikkam

Full Text Available Environmental compounds are known to promote epigenetic transgenerational inheritance of adult onset disease in subsequent generations (F1-F3 following ancestral exposure during fetal gonadal sex determination. The current study was designed to determine if a mixture of plastic derived endocrine disruptor compounds bisphenol-A (BPA, bis(2-ethylhexylphthalate (DEHP and dibutyl phthalate (DBP at two different doses promoted epigenetic transgenerational inheritance of adult onset disease and associated DNA methylation epimutations in sperm. Gestating F0 generation females were exposed to either the "plastics" or "lower dose plastics" mixture during embryonic days 8 to 14 of gonadal sex determination and the incidence of adult onset disease was evaluated in F1 and F3 generation rats. There were significant increases in the incidence of total disease/abnormalities in F1 and F3 generation male and female animals from plastics lineages. Pubertal abnormalities, testis disease, obesity, and ovarian disease (primary ovarian insufficiency and polycystic ovaries were increased in the F3 generation animals. Kidney and prostate disease were only observed in the direct fetally exposed F1 generation plastic lineage animals. Analysis of the plastics lineage F3 generation sperm epigenome previously identified 197 differential DNA methylation regions (DMR in gene promoters, termed epimutations. A number of these transgenerational DMR form a unique direct connection gene network and have previously been shown to correlate with the pathologies identified. Observations demonstrate that a mixture of plastic derived compounds, BPA and phthalates, can promote epigenetic transgenerational inheritance of adult onset disease. The sperm DMR provide potential epigenetic biomarkers for transgenerational disease and/or ancestral environmental exposures.

Repair of lesser tuberosity osteotomy for shoulder arthroplasty: biomechanical evaluation of the Backpack and Dual Row techniques.

Science.gov (United States)

Heckman, Daniel S; Hoover, Stephen A; Weinhold, Paul S; Spang, Jeffrey T; Creighton, R Alexander

2011-04-01

Subscapularis dysfunction following total shoulder arthroplasty can result in permanent loss of function. The lesser tuberosity osteotomy (LTO) has been proposed as a method which utilizes bone-to-bone healing to improve subscapularis function. This study evaluates the biomechanical properties of two described techniques for LTO repair. We hypothesized that a Dual Row repair would be stronger and demonstrate less cyclic displacement than a Backpack repair. Ten matched pairs of cadaveric humeri were dissected, leaving the subscapularis intact, and a lesser tuberosity osteotomy was performed. Matched shoulders were randomized to either a Backpack repair or a Dual Row repair. Repairs were subjected to cyclic loading to 180 N for 500 cycles, followed by ramp-up loading to ultimate failure. Clinical failure was defined as displacement >5 mm after 500 cycles. Displacement after 500 cycles was significantly greater for the Backpack repair (6.9 mm) than for the Dual Row repair (4.6 mm) (P = .007). Most displacement occurred on the first cycle (Backpack, 4.6 mm; Dual Row, 2.1 mm) (P Row repair (3/10). Ultimate tensile strength was significantly greater for the Dual Row repair (632.3 N) than for the Backpack repair (510.9 N) (P = .01). The Dual Row technique is significantly stronger and demonstrates less cyclic displacement than the Backpack technique. Clinical studies are needed to determine the impact of LTO repair technique on subscapularis function following shoulder arthroplasty. Copyright © 2011. Published by Mosby, Inc.

Precambrian-Cambrian boundary in the Tal formation of Garhwal Lesser Himalaya : Rb-Sr age evidence from black shales underlying phosphorites

International Nuclear Information System (INIS)

Sharma, K.K.; Rameshwar Rao, D.; Azmi, R.J.; Gopalan, K.; Pantulu, G.V.C.

1991-01-01

The recently reported faunal evidence for placing the Precambrian-Cambrian boundary within the main phosphorite unit of the Chert-Phosphorite Member of the Tal Formation, Garhwal Lesser Himalaya, is supported by the present report of 626 ± 13 myr for the whole-rock Rb-Sr isochron age of the black shales directly underlying the phosphorite band. (author). 15 refs., 2 figs., 1 tab

Longitudinal research and data collection in primary care.

NARCIS (Netherlands)

Weel, C. van

2005-01-01

PURPOSE: This article reviews examples of and experience with longitudinal research in family medicine. The objective is to use this empirical information to formulate recommendations for improving longitudinal research. METHODS: The article discusses 3 longitudinal studies from the Nijmegen

Genetic favouring of pheomelanin-based pigmentation limits physiological benefits of coloniality in lesser kestrels Falco naumanni.

Science.gov (United States)

Galván, Ismael; Moraleda, Virginia; Otero, Ignacio; Álvarez, Ernesto; Inácio, Ângela

2017-10-01

Pheomelanin contributes to the pigmentation phenotype of animals by producing orange and light brown colours in the integument. However, pheomelanin synthesis in melanocytes requires consumption of glutathione (GSH), the most important intracellular antioxidant. Therefore, a genetic control favouring the production of large amounts of pheomelanin for pigmentation may lead to physiological costs under environmental conditions that promote oxidative stress. We investigated this possibility in the context of breeding coloniality, a reproductive strategy that may affect oxidative stress. We found in lesser kestrel Falco naumanni nestlings that the GSH:GSSG ratio, which decreases with systemic oxidative stress, increased with the size of the colony where they were reared, but the expression in feather melanocytes of five genes involved in pheomelanin synthesis (Slc7a11, Slc45a2, CTNS, MC1R and AGRP) did not vary with colony size. The antioxidant capacity (TEAC) of lesser kestrel nestlings also increased with colony size, but in a manner that depended on Slc7a11 expression and not on the expression of the other genes. Thus, antioxidant capacity increased with colony size only in nestlings least expressing Slc7a11, a gene with a known role in mediating cysteine (a constituent amino acid of GSH) consumption for pheomelanin production. The main predictor of the intensity of pheomelanin-based feather colour was Slc45a2 expression followed in importance by Slc7a11 expression, hence suggesting that the genetic regulation of the pigmentation phenotype mediated by Slc7a11 and a lack of epigenetic lability in this gene limits birds from benefiting from the physiological benefits of coloniality. © 2017 John Wiley & Sons Ltd.

46 CFR 154.176 - Longitudinal contiguous hull structure.

Science.gov (United States)

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Longitudinal contiguous hull structure. 154.176 Section... Equipment Hull Structure § 154.176 Longitudinal contiguous hull structure. (a) The longitudinal contiguous hull structure of a vessel having cargo containment systems without secondary barriers must meet the...

Total Survey Error for Longitudinal Surveys

NARCIS (Netherlands)

Lynn, Peter; Lugtig, P.J.

2016-01-01

This article describes the application of the total survey error paradigm to longitudinal surveys. Several aspects of survey error, and of the interactions between different types of error, are distinct in the longitudinal survey context. Furthermore, error trade-off decisions in survey design and

Internato Longitudinal

Directory of Open Access Journals (Sweden)

Marcelo Marcos Piva Demarzo

Full Text Available O internato médico tem gerado recorrente debate frente às transformações curriculares em andamento no País. A despeito das discussões, um modelo de internato consonante com essas mudanças ainda não foi consistentemente delineado. Neste ensaio, trazemos uma proposta de matriz estruturante para o internato médico. Propomos que o internato médico seja realizado durante os seis anos do curso, de forma longitudinal, tendo como eixo estruturante a clínica da Atenção Básica (AB. Esse modelo de "internato longitudinal" prevê a introdução progressiva na prática clínica, iniciando-se pela AB nos dois primeiros anos, acrescentando-se progressivamente os ambulatórios de especialidades, os estágios hospitalares e demais atividades práticas, alcançando-se, dessa forma, o rol de diversidade e complexidade previsto para o egresso da escola médica.

Longitudinal muscle dysfunction in achalasia esophagus and its relevance.

Science.gov (United States)

Mittal, Ravinder K; Hong, Su Jin; Bhargava, Valmik

2013-04-01

Muscularis propria of the esophagus is organized into circular and longitudinal muscle layers. Goal of this review is to summarize the role of longitudinal muscle in physiology and pathophysiology of esophageal sensory and motor function. Simultaneous manometry and ultrasound imaging that measure circular and longitudinal muscle contraction respectively reveal that during peristalsis 2 layers of the esophagus contract in perfect synchrony. On the other hand, during transient relaxation of the lower esophageal sphincter (LES), longitudinal muscle contracts independently of circular muscle. Recent studies provide novel insights, i.e., longitudinal muscle contraction of the esophagus induces LES relaxation and possibly descending relaxation of the esophagus. In achalasia esophagus and other motility disorders there is discoordination between the 2 muscle layers. Longitudinal muscle contraction patterns are different in the recently described three types of achalasia identified by high-resolution manometry. Robust contraction of the longitudinal muscle in type II achalasia causes pan-esophageal pressurization and is the mechanism of whatever little esophageal emptying that take place in the absence of peristalsis and impaired LES relaxation. It may be that preserved longitudinal muscle contraction is also the reason for superior outcome to medical/surgical therapy in type II achalasia esophagus. Prolonged contractions of longitudinal muscles of the esophagus is a possible mechanism of heartburn and "angina like" pain seen in esophageal motility disorders and possibly achalasia esophagus. Novel techniques to record longitudinal muscle contraction are on the horizon. Neuro-pharmacologic control of circular and longitudinal muscles is different, which provides an important opportunity for the development of novel pharmacological therapies to treat sensory and motor disorders of the esophagus.

Summary of longitudinal instabilities workshop

Energy Technology Data Exchange (ETDEWEB)

Chasman, R.

1976-01-01

A five-day ISABELLE workshop on longitudinal instabilities was held at Brookhaven, August 9-13, 1976. About a dozen outside accelerator experts, both from Europe and the U.S.A., joined the local staff for discussions of longitudinal instabilities in ISABELLE. An agenda of talks was scheduled for the first day of the workshop. Later during the week, a presentation was given on the subject ''A more rigorous treatment of Landau damping in longitudinal beam instabilities''. A few progress meetings were held in which disagreements regarding calculations of coupling impedances were clarified. A summary session was held on the last day. Heavy emphasis was put on single bunched beam instabilities in the microwave region extending above the cut-off frequency of the ISABELLE vacuum chamber.

A virulent clone of Devriesea agamarum affects endangered Lesser Antillean iguanas (Iguana delicatissima).

Science.gov (United States)

Hellebuyck, Tom; Questel, Karl; Pasmans, Frank; Brantegem, Leen Van; Philip, Pascal; Martel, An

2017-10-02

Infectious diseases affecting wildlife are drivers of global biodiversity loss. Here we report a bacterial threat to endangered wild reptiles. Since April 2011, a severe skin disease has affected free-ranging, endangered Lesser Antillean iguanas (Iguana delicatissima) on the French Caribbean island of Saint Barthélemy and we identified Devriesea agamarum as the causative agent. The presence of this bacterium was also demonstrated in healthy lizards (anoles) co-inhabiting the island. All isolates from the iguanas corresponded to a single AFLP genotype that until now has exclusively been associated with infections in lizard species in captivity. The clonal relatedness of the isolates and recent emergence of the disease suggest recent arrival of a virulent D. agamarum clone on the island. The presence of healthy but infected lizards suggests the presence of asymptomatic reservoir hosts. This is the first description of a bacterial disease that poses a conservation threat towards free-ranging squamates.

Gender differences in the accuracy of time-dependent blood pressure indices for predicting coronary heart disease: A random-effects modeling approach.

Science.gov (United States)

Brant, Larry J; Ferrucci, Luigi; Sheng, Shan L; Concin, Hans; Zonderman, Alan B; Kelleher, Cecily C; Longo, Dan L; Ulmer, Hanno; Strasak, Alexander M

2010-12-01

Previous studies on blood pressure (BP) indices as a predictor of coronary heart disease (CHD) have provided equivocal results and generally relied on Cox proportional hazards regression methodology, with age and sex accounting for most of the predictive capability of the model. The aim of the present study was to use serially collected BP measurements to examine age-and gender-related differences in BP indices for predicting CHD. The predictive accuracy of time-dependent BP indices for CHD was investigated using a method of risk prediction based on posterior probabilities calculated from mixed-effects regression to utilize intraindividual differences in serial BP measurements according to age changes within gender groups. Data were collected prospectively from 2 community-dwelling cohort studies in the United States (Baltimore Longitudinal Study of Aging [BLSA]) and Europe (Vorarlberg Health Monitoring and Promotion Program [VHM&PP]). The study comprised 152,633 participants (aged 30-74 years) and 610,061 BP measurements. During mean follow-up of 7.5 years, 2457 nonfatal and fatal CHD events were observed. In both study populations, pulse pressure (PP) and systolic blood pressure (SBP) performed best as individual predictors of CHD in women (area under the receiver operating characteristic curve [AUC(ROC)] was between 0.83 and 0.85 for PP, and between 0.77 and 0.81 for SBP). Mean arterial pressure (MAP) and diastolic blood pressure (DBP) performed better for men (AUC(ROC) = 0.67 and 0.65 for MAP and DBP, respectively, in the BLSA; AUC(ROC) = 0.77 and 0.75 in the VHM&PP) than for women (AUC(ROC) = 0.60 for both MAP and DBP in the BLSA; AUC(ROC) = 0.75 and 0.52, respectively, in the VHM&PP). The degree of discrimination in both populations was overall greater but more varied for all BP indices for women (AUC(ROC) estimates between 0.85 [PP in the VHM&PP] and 0.52 [DBP in the VHM&PP]) than for men (AUC(ROC) estimates between 0.78 [MAP + PP in the VHM&PP] and 0.63 [PP

Study of CSR longitudinal bunch compression cavity

International Nuclear Information System (INIS)

Yin Dayu; Li Peng; Liu Yong; Xie Qingchun

2009-01-01

The scheme of longitudinal bunch compression cavity for the Cooling Storage Ring (CSR)is an important issue. Plasma physics experiments require high density heavy ion beam and short pulsed bunch,which can be produced by non-adiabatic compression of bunch implemented by a fast compression with 90 degree rotation in the longitudinal phase space. The phase space rotation in fast compression is initiated by a fast jump of the RF-voltage amplitude. For this purpose, the CSR longitudinal bunch compression cavity, loaded with FINEMET-FT-1M is studied and simulated with MAFIA code. In this paper, the CSR longitudinal bunch compression cavity is simulated and the initial bunch length of 238 U 72+ with 250 MeV/u will be compressed from 200 ns to 50 ns.The construction and RF properties of the CSR longitudinal bunch compression cavity are simulated and calculated also with MAFIA code. The operation frequency of the cavity is 1.15 MHz with peak voltage of 80 kV, and the cavity can be used to compress heavy ions in the CSR. (authors)

Microscopic aspects of electrosensory system on the partially euryhaline lesser guitarfish

Directory of Open Access Journals (Sweden)

BIANCA S. RANGEL

2017-12-01

Full Text Available ABSTRACT The electrosensory system on elasmobranchs consists of subcutaneous electroreceptor organs known as ampullae of Lorenzini. The present study investigated the ampullae of Lorenzini morphology of the lesser guitarfish Zapteryx brevirostris, using light microscopy and scanning electron microscopy. The pore number found in the ventral skin surface is much higher than that found in the dorsal portion, characteristic of species that inhabit the euphotic zone. Under light microscopy it was possible to observe that the wall canal consists of a single layer of squamous epithelial cells. The canal features distal expansion, where the ampullae are located with up to six alveoli. The sensory epithelium of ampullae is composed by cubic cells, with oval nucleus, restricted to the interior of the alveoli. With analysis the clusters under scanning electron microscopy, it was possible to observe the structure and the random arrangement of individual ampullae, canals and nerves. The distribution of dorsal and ventral pores and ampullae in Z. brevirostris resembled those of the same family. The number of alveoli per ampullae was similar to that found in euryhaline elasmobranchs species, suggesting that the morphological organization in Z. brevirostris is linked to its possible evolutionary transitory position among batoids.

Probabilistic hurricane-induced storm surge hazard assessment in Guadeloupe, Lesser Antilles

Science.gov (United States)

Krien, Y.; Dudon, B.; Roger, J.; Zahibo, N.

2015-08-01

Current storm surge hazard maps in the French West Indies are essentially based on simple statistical methods using limited historical data and early low-resolution models which do not take the effect of waves into account. In this paper, we infer new 100-year and 1000-year surge levels in Guadeloupe from the numerical modelling of storm surges induced by a large set of synthetic events that are in statistical agreement with features of historical hurricanes in the North Atlantic Basin between 1980 and 2011. Computations are performed using the wave-current coupled model ADCIRC-SWAN with high grid resolutions (up to 40-60 m) in the coastal and wave dissipation areas. This model is validated against observations during past events such as hurricane HUGO (1989). Results are generally found to be in reasonable agreement with past studies in areas where surge is essentially wind-driven, but found to differ significantly in coastal regions where the transfer of momentum from waves to the water column constitutes a non-negligible part of the total surge. The methodology, which can be applied to other islands in the Lesser Antilles, allows storm surge level maps to be obtained that can be of major interest for coastal planners and decision makers in terms of risk management.

Simultaneous maximum a posteriori longitudinal PET image reconstruction

Science.gov (United States)

Ellis, Sam; Reader, Andrew J.

2017-09-01

Positron emission tomography (PET) is frequently used to monitor functional changes that occur over extended time scales, for example in longitudinal oncology PET protocols that include routine clinical follow-up scans to assess the efficacy of a course of treatment. In these contexts PET datasets are currently reconstructed into images using single-dataset reconstruction methods. Inspired by recently proposed joint PET-MR reconstruction methods, we propose to reconstruct longitudinal datasets simultaneously by using a joint penalty term in order to exploit the high degree of similarity between longitudinal images. We achieved this by penalising voxel-wise differences between pairs of longitudinal PET images in a one-step-late maximum a posteriori (MAP) fashion, resulting in the MAP simultaneous longitudinal reconstruction (SLR) method. The proposed method reduced reconstruction errors and visually improved images relative to standard maximum likelihood expectation-maximisation (ML-EM) in simulated 2D longitudinal brain tumour scans. In reconstructions of split real 3D data with inserted simulated tumours, noise across images reconstructed with MAP-SLR was reduced to levels equivalent to doubling the number of detected counts when using ML-EM. Furthermore, quantification of tumour activities was largely preserved over a variety of longitudinal tumour changes, including changes in size and activity, with larger changes inducing larger biases relative to standard ML-EM reconstructions. Similar improvements were observed for a range of counts levels, demonstrating the robustness of the method when used with a single penalty strength. The results suggest that longitudinal regularisation is a simple but effective method of improving reconstructed PET images without using resolution degrading priors.

Longitudinal single-bunch instabilities

International Nuclear Information System (INIS)

Migliorati, M.; Palumbo, L.; Rome Univ. La Sapienza, Rome

2001-02-01

After introducing the concepts of longitudinal wakefield and coupling impedance, it is reviewed the theory of longitudinal single-bunch collective effects in storage rings. From the Fokker-Planck equation it is first derived the stationary solution describing the natural single-bunch regime, and then treat the problem of microwave instability, showing the different approaches used for estimating the threshold current. The lecture is ended with the semi-empirical laws that allow everyone to obtain the single-bunch behaviour above threshold, and with a description of the simulation codes that are now reliable tools for investigating all these effects

LIA longitudinal coupling impedance

International Nuclear Information System (INIS)

Faltens, A.

1980-01-01

The beam generated fields enter into the problems of waveform generation and longitudinal stability. In the former, provision must be made for the longitudinally defocusing forces due to the space charge and the beam loading effects on the accelerating voltage due to the current of a presumably known bunch. In the latter, the concern is for the growth of unintentional perturbations to unacceptably large values through the interaction of the charge and current fluctuations with the rest of the beam and the surrounding structures. These beam generated electric fields may be related to the beam current through a coupling impedance

Longitudinal beam dynamics

International Nuclear Information System (INIS)

Tecker, F

2014-01-01

The course gives a summary of longitudinal beam dynamics for both linear and circular accelerators. After discussing different types of acceleration methods and synchronism conditions, it focuses on the particle motion in synchrotrons

Butyrate Inhibits Cancerous HCT116 Colon Cell Proliferation but to a Lesser Extent in Noncancerous NCM460 Colon Cells.

Science.gov (United States)

Zeng, Huawei; Taussig, David P; Cheng, Wen-Hsing; Johnson, LuAnn K; Hakkak, Reza

2017-01-01

Butyrate, an intestinal microbiota metabolite of dietary fiber, exhibits chemoprevention effects on colon cancer development. However, the mechanistic action of butyrate remains to be determined. We hypothesize that butyrate inhibits cancerous cell proliferation but to a lesser extent in noncancerous cells through regulating apoptosis and cellular-signaling pathways. We tested this hypothesis by exposing cancerous HCT116 or non-cancerous NCM460 colon cells to physiologically relevant doses of butyrate. Cellular responses to butyrate were characterized by Western analysis, fluorescent microscopy, acetylation, and DNA fragmentation analyses. Butyrate inhibited cell proliferation, and led to an induction of apoptosis, genomic DNA fragmentation in HCT116 cells, but to a lesser extent in NCM460 cells. Although butyrate increased H3 histone deacetylation and p21 tumor suppressor expression in both cell types, p21 protein level was greater with intense expression around the nuclei in HCT116 cells when compared with that in NCM460 cells. Furthermore, butyrate treatment increased the phosphorylation of extracellular-regulated kinase 1/2 (p-ERK1/2), a survival signal, in NCM460 cells while it decreased p-ERK1/2 in HCT116 cells. Taken together, the activation of survival signaling in NCM460 cells and apoptotic potential in HCT116 cells may confer the increased sensitivity of cancerous colon cells to butyrate in comparison with noncancerous colon cells.

Trauma centers with higher rates of angiography have a lesser incidence of splenectomy in the management of blunt splenic injury.

Science.gov (United States)

Capecci, Louis M; Jeremitsky, Elan; Smith, R Stephen; Philp, Frances

2015-10-01

Nonoperative management (NOM) for blunt splenic injury (BSI) is well-established. Angiography (ANGIO) has been shown to improve success rates with NOM. Protocols for NOM are not standardized and vary widely between centers. We hypothesized that trauma centers that performed ANGIO at a greater rate would demonstrate decreased rates of splenectomy compared with trauma centers that used ANGIO less frequently. A large, multicenter, statewide database (Pennsylvania Trauma Systems Foundation) from 2007 to 2011 was used to generate the study cohort of patients with BSI (age ≥ 13). The cohort was divided into 2 populations based on admission to centers with high (≥13%) or low (Splenectomy rates were then compared between the 2 groups, and multivariable logistic regression for predictors of splenectomy (failed NOM) were also performed. The overall rate of splenectomy in the entire cohort was 21.0% (1,120 of 5,333 BSI patients). The high ANGIO group had a lesser rate of splenectoy compared with the low ANGIO group (19% vs 24%; P splenectomy compared with low ANGIO centers (odds ratio, 0.68; 95% CI 0.58-0.80; P splenectomy rates compared with centers with lesser rate of ANGIO. Inclusion of angiographic protocols for NOM of BSI should be considered strongly. Copyright © 2015 Elsevier Inc. All rights reserved.

Longitudinal Control for Mengshi Autonomous Vehicle via Cloud Model

Science.gov (United States)

Gao, H. B.; Zhang, X. Y.; Li, D. Y.; Liu, Y. C.

2018-03-01

Dynamic robustness and stability control is a requirement for self-driving of autonomous vehicle. Longitudinal control method of autonomous is a key technique which has drawn the attention of industry and academe. In this paper, we present a longitudinal control algorithm based on cloud model for Mengshi autonomous vehicle to ensure the dynamic stability and tracking performance of Mengshi autonomous vehicle. An experiments is applied to test the implementation of the longitudinal control algorithm. Empirical results show that if the longitudinal control algorithm based Gauss cloud model are applied to calculate the acceleration, and the vehicles drive at different speeds, a stable longitudinal control effect is achieved.

Ring RF and longitudinal dynamics in the SNS

International Nuclear Information System (INIS)

Blaskiewicz, M.; Brennan, J.M.; Brodowski, J.; Delong, J.; Meth, M.; Onillon, E.; Zaltsman, A.

2000-01-01

Average beam currents of 40 A will be present in the Spallation Neutron Source. Even though the entire cycle time is only one synchrotron oscillation the longitudinal phase space determines peak beam current and momentum spread. Both factors play a role in space charge and instability dynamics. Longitudinal simulations with beam loading and longitudinal space charge have been done in the design phase

Boosted Multivariate Trees for Longitudinal Data

Science.gov (United States)

Pande, Amol; Li, Liang; Rajeswaran, Jeevanantham; Ehrlinger, John; Kogalur, Udaya B.; Blackstone, Eugene H.; Ishwaran, Hemant

2017-01-01

Machine learning methods provide a powerful approach for analyzing longitudinal data in which repeated measurements are observed for a subject over time. We boost multivariate trees to fit a novel flexible semi-nonparametric marginal model for longitudinal data. In this model, features are assumed to be nonparametric, while feature-time interactions are modeled semi-nonparametrically utilizing P-splines with estimated smoothing parameter. In order to avoid overfitting, we describe a relatively simple in sample cross-validation method which can be used to estimate the optimal boosting iteration and which has the surprising added benefit of stabilizing certain parameter estimates. Our new multivariate tree boosting method is shown to be highly flexible, robust to covariance misspecification and unbalanced designs, and resistant to overfitting in high dimensions. Feature selection can be used to identify important features and feature-time interactions. An application to longitudinal data of forced 1-second lung expiratory volume (FEV1) for lung transplant patients identifies an important feature-time interaction and illustrates the ease with which our method can find complex relationships in longitudinal data. PMID:29249866

Effect of di(n-butyl) phthalate on testicular oxidative damage and antioxidant enzymes in hyperthyroid rats.

Science.gov (United States)

Lee, Ena; Ahn, Mee Young; Kim, Hee Jin; Kim, In Young; Han, Soon Young; Kang, Tae Seok; Hong, Jin Hwan; Park, Kui Lea; Lee, Byung Mu; Kim, Hyung Sik

2007-06-01

This study compared the effects of di(n-butyl) phthalate (DBP) on the oxidative damage and antioxidant enzymes activity in testes of hyperthyroid rats. Hyperthyroidism was induced in pubertal male rats by intraperitoneal injection of triiodothyronine (T3, 10 microg/kg body weight) for 30 days. An oral dose of DBP (750 mg/kg) was administered simultaneously to normal or hyperthyroid (T3) rats over a 30-day period. No changes in body weight were observed in the hyperthyroid groups (T3, T3 + DBP) compared with controls. There were significantly higher serum T3 levels observed in the hyperthyroid rats than in the control, but the serum thyroid stimulating hormone levels were markedly lower in the hyperthyroid rats. DBP significantly decreased the weight of the testes in the normal (DBP) and hyperthyroid (T3 + DBP) groups. The serum testosterone concentrations were significantly lower in only DBP group. DBP significantly increased the 8-hydroxy-2-deoxyguanosine (8-OHdG) level in the testes, whereas the DBP-induced 8-OHdG levels were slightly higher in T3 + DBP group. Superoxide dismutase and glutathione peroxidase activities were significantly higher in the testes of the DBP or T3 + DBP groups. Catalase (CAT) activity was significantly higher in the DBP treatment group, but the T3 + DBP group showed slightly lower DBP-induced CAT activity. The testicular expression of thyroid hormone receptor alpha-1 (TRalpha-1) was significantly higher in the DBP groups, and androgen receptor (AR) expression was not detected in the DBP treatment group. In addition, DBP significantly increased the peroxisome proliferator-activated receptor-r (PPAR-r) levels in the testis. These results suggest that hyperthyroidism can cause a change in the expression level of PPAR-r in testes, and may increase the levels of oxidative damage induced by the metabolic activation of DBP.

Longitudinal and bulk viscosities of Lennard-Jones fluids

Science.gov (United States)

Tankeshwar, K.; Pathak, K. N.; Ranganathan, S.

1996-12-01

Expressions for the longitudinal and bulk viscosities have been derived using Green Kubo formulae involving the time integral of the longitudinal and bulk stress autocorrelation functions. The time evolution of stress autocorrelation functions are determined using the Mori formalism and a memory function which is obtained from the Mori equation of motion. The memory function is of hyperbolic secant form and involves two parameters which are related to the microscopic sum rules of the respective autocorrelation function. We have derived expressions for the zeroth-, second-and fourth- order sum rules of the longitudinal and bulk stress autocorrelation functions. These involve static correlation functions up to four particles. The final expressions for these have been put in a form suitable for numerical calculations using low- order decoupling approximations. The numerical results have been obtained for the sum rules of longitudinal and bulk stress autocorrelation functions. These have been used to calculate the longitudinal and bulk viscosities and time evolution of the longitudinal stress autocorrelation function of the Lennard-Jones fluids over wide ranges of densities and temperatures. We have compared our results with the available computer simulation data and found reasonable agreement.

Longitudinal beam compression for heavy-ion inertial fusion

International Nuclear Information System (INIS)

Ho, D.D.M.; Brandon, S.T.

1991-01-01

A scheme is described for compressing a heavy-ion beam longitudinally in such a way that the compressed pulse has uniform line-charge density and longitudinal momentum. Attaining these conditions will be important in the final focusing of a beam on a small fuel capsule in an inertial confinement fusion reactor. The longitudinal dynamics can be approximately described by a one-dimensional (1-D) fluid model for charged particles. Recognizing the similarity between the 1-D charged particle equations of motion and the 1-D equations for ideal-gas flow permits us to calculate the evolution of the line-charge density and velocity profile using self-similar solutions and the method of characteristics, developed for unsteady supersonic gas dynamics, for different regions along the beam. Simple physical arguments show that although the longitudinal and transverse temperatures vary along the beam following the adiabatic laws, no substantial longitudinal and transverse emittance growth is to be expected. Particle-in-cell simulations confirm all the physical arguments. The compressed beam has negligible longitudinal momentum spread and can therefore avoid chromatic aberrations in final focus. (author) 24 refs., 5 figs., 1 tab

Longitudinal research and data collection in primary care.

Science.gov (United States)

van Weel, Chris

2005-01-01

This article reviews examples of and experience with longitudinal research in family medicine. The objective is to use this empirical information to formulate recommendations for improving longitudinal research. The article discusses 3 longitudinal studies from the Nijmegen academic family practice research network: 1 on the prognosis of depression and 1 each on the prognosis of and outcomes of care for type 2 diabetes mellitus. The Nijmegen network has recorded all episodes of morbidity encountered in Dutch family medicine since 1971 in a stable practice population. This network's experience is evaluated to identify lessons that may help other practice-based research networks (PBRNs) in pursuing longitudinal research. In terms of external conditions (conditions related to the general setting), the stability of a population and a high level of continuity of care substantially enhance the ability to perform longitudinal research. In terms of internal conditions (conditions related to the PBRN), motivation of family physicians and their staff to conduct ongoing data collection, and their ownership of the data are key for success. Other critical internal conditions include standardization of data; collection of data by clinician-friendly means; training of family physicians and their staff in data collection, as well as meetings for discussion of this task; provision of feedback to practices on the research findings; use of standard procedures to promote adherence to data collection; availability of facilities for regular measurement of patients' health status or chart review; and use of mechanisms for tracking patients who leave the practice area. Insight from existing experience suggests that longitudinal research can be enhanced in PBRNs. The best way forward is to build longitudinal data collection by drawing on lessons from successful studies. Primary care research policy should advocate for a role of longitudinal research and stimulate its development in PBRNs

The association of maternal prenatal psychosocial stress with vascular function in the child at age 10-11 years: findings from the Avon longitudinal study of parents and children.

Science.gov (United States)

van Dijk, Aimée E; Dawe, Karen; Deanfield, John; Stronks, Karien; Gemke, Reinoud J B J; Vrijkotte, Tanja G M; Lawlor, Debbie A

2014-09-01

To investigate whether (1) maternal psychosocial stress (depression/anxiety) during pregnancy is associated with offspring vascular function and (2) whether any association differs depending on the gestational timing of exposure to stress. We also investigated whether any association is likely to be due to intrauterine mechanisms by (3) comparing with the association of paternal stress with offspring vascular function and (4) examining whether any prenatal association is explained by maternal postnatal stress. Associations were examined in a UK birth cohort, with offspring outcomes (systolic and diastolic blood pressure, SBP and DBP, endothelial function assessed by brachial artery flow-mediated dilatation (FMD); arterial stiffness assessed by carotid to radial pulse wave velocity (PWV), brachial artery distensibility (DC), and brachial artery diameter (BD) assessed at age 10-11 years (n = 4,318). Maternal depressive symptoms and anxiety were assessed at 18 and 32 weeks gestation and 8 months postnatally. Paternal symptoms were assessed at week 19. With the exception of DBP and BD, there were no associations of maternal depressive symptoms with any of the vascular outcomes. Maternal depressive and anxiety symptoms were associated with lower offspring DBP and wider BD, though the latter attenuated to the null with adjustment for confounding factors. Paternal symptoms were not associated with offspring outcomes. Maternal postnatal depressive symptoms were associated with lower offspring SBP. We found no evidence to support the hypothesis that maternal stress during pregnancy adversely affects offspring vascular function at age 10-12 years via intrauterine mechanisms. © Authors 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Longitudinal drop-out and weighting against its bias

Directory of Open Access Journals (Sweden)

Steffen C. E. Schmidt

2017-12-01

Full Text Available Abstract Background The bias caused by drop-out is an important factor in large population-based epidemiological studies. Many studies account for it by weighting their longitudinal data, but to date there is no detailed final approach for how to conduct these weights. Methods In this study we describe the observed longitudinal bias and a three-step longitudinal weighting approach used for the longitudinal data in the MoMo baseline (N = 4528, 4–17 years and wave 1 study with 2807 (62% participants between 2003 and 2012. Results The most meaningful drop-out predictors were socioeconomic status of the household, socioeconomic characteristics of the mother and daily TV usage. Weighting reduced the bias between the longitudinal participants and the baseline sample, and also increased variance by 5% to 35% with a final weighting efficiency of 41.67%. Conclusions We conclude that a weighting procedure is important to reduce longitudinal bias in health-oriented epidemiological studies and suggest identifying the most influencing variables in the first step, then use logistic regression modeling to calculate the inverse of the probability of participation in the second step, and finally trim and standardize the weights in the third step.

Longitudinal feedback system for PEP

International Nuclear Information System (INIS)

Allen, M.A.; Cornacchia, M.; Millich, A.

1979-02-01

Whether the wide bandwidth longitudinal feedback system described in this paper is made to act on the individual modes in frequency domain or on the individual bunches in time domain, it represents a clean and efficient way of damping the longitudinal oscillations without influencing other beam parameters such as bunch shape or synchrotron frequency distribution. The frequency domain feedback presents the advantage of providing information on which modes are unstable and on their risetimes, which may be helpful in locating dangerous resonators in the ring

Longitudinal fluctuations and decorrelation of anisotropic flow

Energy Technology Data Exchange (ETDEWEB)

Pang, Long-Gang [Frankfurt Institute for Advanced Studies, Ruth-Moufang-Strasse 1, 60438 Frankfurt am Main (Germany); Petersen, Hannah [Frankfurt Institute for Advanced Studies, Ruth-Moufang-Strasse 1, 60438 Frankfurt am Main (Germany); Institute for Theoretical Physics, Goethe University, Max-von-Laue-Strasse 1, 60438 Frankfurt am Main (Germany); GSI Helmholtzzentrum für Schwerionenforschung, Planckstr. 1, 64291 Darmstadt (Germany); Qin, Guang-You [Key Laboratory of Quark & Lepton Physics (MOE) and Institute of Particle Physics, Central China Normal University, Wuhan 430079 (China); Roy, Victor [Institute for Theoretical Physics, Goethe University, Max-von-Laue-Strasse 1, 60438 Frankfurt am Main (Germany); Wang, Xin-Nian [Key Laboratory of Quark & Lepton Physics (MOE) and Institute of Particle Physics, Central China Normal University, Wuhan 430079 (China); Nuclear Science Division MS70R0319, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

2016-12-15

We investigate the decorrelation of 2nd and 3rd order anisotropic flow for charged particles in two different pseudo rapidity (η) windows by varying the pseudo rapidity gap, in an event-by-event (3+1)D ideal hydrodynamic model, with fluctuating initial conditions from A Multi-Phase Transport (AMPT) model. We visualize the parton distribution at initial state for Pb+Pb collisions at LHC and Au+Au collisions at RHIC, and demonstrate the longitudinal fluctuations originating from the asymmetry between forward and backward going participants, the fluctuations of the string length and the fluctuations due to finite number of partons at different beam energies. The decorrelation of anisotropic flow of final hadrons with large η gaps is found to originate from the spatial decorrelation along the longitudinal direction in the AMPT initial conditions through hydrodynamic evolution. The agreement between our results and recent CMS data in most centralities suggests that the string-like mechanism of initial parton production in AMPT model captures the initial longitudinal fluctuation that is responsible for the measured decorrelation of anisotropic flow in Pb+Pb collisions at LHC. Our predictions for Au+Au collisions at the highest RHIC energy show stronger longitudinal decorrelation than at LHC, indicating larger longitudinal fluctuations at lower beam energies.

The lesser evil? Initiating a benzodiazepine prescription in general practice

Science.gov (United States)

Anthierens, Sibyl; Habraken, Hilde; Petrovic, Mirko; Christiaens, Thierry

2007-01-01

Objective Chronic benzodiazepine (BZD) use is widespread and linked with adverse effects. There is consensus concerning the importance of initiating BZD as a crucial moment. Nevertheless specific research in this field is lacking. This paper addresses the views of GPs on why they start prescribing BZDs to first-time users. Design Qualitative study with five focus groups analysed using a systematic content analysis. Setting Regions of Ghent and Brussels in Belgium. Subjects A total of 35 general practitioners. Main outcome measure The GPs’ perspective on their initiating of BZD prescribing. Results GPs reported that they are cautious in initiating BZD usage. At the same time, GPs feel overwhelmed by the psychosocial problems of their patients. They show empathy by prescribing. They feel in certain situations there are no other solutions and they experience BZDs as the lesser evil. They admit to resorting to BZDs because of time restraint and lack of alternatives. GPs do not perceive the addictive nature of BZD consumption as a problem with first-time users. GPs do not specifically mention patients’ demand as an element for starting. Conclusion The main concern of GPs is to help the patient. GPs should be aware of the addictive nature of BZD even in low doses and a non-pharmacological approach should be seen as the best first approach. If GPs decide to prescribe a BZD they should make plain to the patient that the medication is only a “temporary” solution with clear agreements with regard to medication withdrawal. PMID:18041658

Posterior longitudinal ligament status in cervical spine bilateral facet dislocations

International Nuclear Information System (INIS)

Carrino, John A.; Manton, Geoffrey L.; Morrison, William B.; Flanders, Adam E.; Vaccaro, Alex R.; Schweitzer, Mark E.

2006-01-01

It is generally accepted that cervical spine bilateral facet dislocation results in complete disruption of the posterior longitudinal ligament. The goal of this study was to evaluate the integrity of numerous spine-stabilizing structures by MRI, and to determine if any associations between injury patterns exist with respect to the posterior longitudinal ligament status. Retrospective case series. A retrospective review was performed of 30 cervical spine injury subjects with bilateral facet dislocation. Assessment of 1.5T MRI images was carried out for: intervertebral disc disruption, facet fracture, and ligamentous disruption. Statistical analyses were performed to evaluate for associations between various injury patterns and posterior longitudinal ligament status. The frequency of MRI abnormalities was: anterior longitudinal ligament disruption (26.7%), disc herniation or disruption (90%), posterior longitudinal ligament disruption (40%), facet fracture (63.3%) and disruption of the posterior column ligament complex (97%). There were no significant associations between injury to the posterior longitudinal ligament and other structures. Compared to surgical reports, MRI was accurate for determining the status for 24 of 26 ligaments (three of three anterior longitudinal ligament, seven of nine posterior longitudinal ligament, and 14 of 14 posterior column ligament complex) but generated false negatives in two instances (in both MRI showed an intact posterior longitudinal ligament that was torn at surgery). (orig.)

Existence of longitudinal waves in pre-stressed anisotropic elastic ...

Indian Academy of Sciences (India)

waves is truly longitudinal. Longitudinal wave in an anisotropic elastic medium is defined as the wave motion in which the particle motion (i.e., the. Keywords. General anisotropy; elastic stiffness; pre-stress; group velocity; ray direction; longitudinal waves; polarization. J. Earth Syst. Sci. 118, No. 6, December 2009, pp. 677– ...

Isotopic composition of strontium in three basalt-andesite centers along the Lesser Antilles arc

Science.gov (United States)

Hedge, C.E.; Lewis, J.F.

1971-01-01

Si87/Sr86 ratios have been determined for lavas and py lastic rocks from three basalt-andesite centers along the Lesser Antilles arc-Mt. Misery on the island of St. Kitts, Soufriere on the island of St. Vincent, and Carriacou, an island of The Grenadines. The average Si87/Sr86 content of these rocks is 0.7038 for Mt. Misery, 0.7041 for Soufriere, and 0.7053 for Carriacou. All the Sr87/Sr86 values from each center are the same within analytical uncertainty (??0.0002). The constancy of strontium isotopic data within each center supports the hypothesis that basalts and andesites for each specific center investigated are generated from the same source - in agreement with petrographic and major- and minor-element data. Strontium isotopic compositions and elemental concentrations, particularly of strontium and nickel, indicate that this source was mantle peridotite and that the relationship between the respective basalts and andesites is probably fractional crystallization. ?? 1971 Springer-Verlag.

Parameter optimization method for longitudinal vibration absorber of ship shaft system

Directory of Open Access Journals (Sweden)

LIU Jinlin

2017-05-01

Full Text Available The longitudinal vibration of the ship shaft system is the one of the most important factors of hull stern vibration, and it can be effectively minimized by installing a longitudinal vibration absorber. In this way, the vibration and noise of ships can be brought under control. However, the parameters of longitudinal vibration absorbers have a great influence on the vibration characteristics of the shaft system. As such, a certain shafting testing platform was studied as the object on which a finite model was built, and the relationship between longitudinal stiffness and longitudinal vibration in the shaft system was analyzed in a straight alignment state. Furthermore, a longitudinal damping model of the shaft system was built in which the parameters of the vibration absorber were non-dimensionalized, the weight of the vibration absorber was set as a constant, and an optimizing algorithm was used to calculate the optimized stiffness and damping coefficient of the vibration absorber. Finally, the longitudinal vibration frequency response of the shafting testing platform before and after optimizing the parameters of the longitudinal vibration absorber were compared, and the results indicated that the longitudinal vibration of the shafting testing platform was decreased effectively, which suggests that it could provide a theoretical foundation for the parameter optimization of longitudinal vibration absorbers.

PREVENTION OF POLYURETHANE OXIDATIVE DEGRADATION WITH PHENOLIC-ANTIOXIDANTS COVALENTLY ATTACHED TO THE HARD SEGMENTS: STRUCTURE FUNCTION RELATIONSHIPS

Science.gov (United States)

Stachelek, Stanley J; Alferiev, Ivan; Ueda, Masako; Eckels, Edward C.; Gleason, Kevin T.; Levy, Robert J

2010-01-01

Oxidative degradation of the polyurethane elastomeric (PU) components greatly reduces the efficacy of PU containing cardiovascular devices. Covalently appending the phenol-based antioxidant, 4-substituted 2,6-di-tert-butylphenol (DBP), to PU hard segments effectively reduced oxidative degradation of the PU in vivo and in vitro in prior studies by our group. In these experiments we analyze the contribution of the tethering molecule to the antioxidant capabilities of the DBP modified PU. Bromoalkylation chemistry was used to link DBP to the hard segment of the polyether polyurethane, Tecothane, via our original linker (PU-DBP), or variants containing side chains with 1 (PU-C-DBP) or 3 (PU-3C-DBP) carbons. Two additional DBP variants were fabricated in which the DBP group was appended to the alkyl chain via an oxygen atom (PU-O-DBP) or an amide linkage in the middle of the tether (PU-NHCO-DBP). All DBP variant films and unmodified control films were subject to oxidative degradation via 15 day immersion in a solution of 20% H2O2 + 0.1 M CoCl2. At the end of the oxidation protocol films were analyzed for the presence of oxidation related endpoints via scanning electron microscopy, contact angle measurements and Fourier transformation infrared spectroscopy (FTIR). All DBP containing variants resisted oxidation damage significantly better than the unmodified control PU. SEM analysis of oxidized PU-C-DBP and PU-O-DBP showed evidence of surface cracking consistent with oxidative degradation of the PU surfaces. Similarly there was a trend in increased ether cross-linking, a marker for oxidative degradation, in PU-C-DBP and PU-NHCO-DBP films. Consistent with these FTIR results, both PU-C-DBP and PU-NHCO-DBP had significant reductions in measured surface hydrophobicity as a result of oxidation. These data show for the first time that the choice of linker molecule significantly affects the efficiency of the linked phenolic antioxidant. PMID:20306526

Modelling, simulation and applications of longitudinal train dynamics

Science.gov (United States)

Cole, Colin; Spiryagin, Maksym; Wu, Qing; Sun, Yan Quan

2017-10-01

Significant developments in longitudinal train simulation and an overview of the approaches to train models and modelling vehicle force inputs are firstly presented. The most important modelling task, that of the wagon connection, consisting of energy absorption devices such as draft gears and buffers, draw gear stiffness, coupler slack and structural stiffness is then presented. Detailed attention is given to the modelling approaches for friction wedge damped and polymer draft gears. A significant issue in longitudinal train dynamics is the modelling and calculation of the input forces - the co-dimensional problem. The need to push traction performances higher has led to research and improvement in the accuracy of traction modelling which is discussed. A co-simulation method that combines longitudinal train simulation, locomotive traction control and locomotive vehicle dynamics is presented. The modelling of other forces, braking propulsion resistance, curve drag and grade forces are also discussed. As extensions to conventional longitudinal train dynamics, lateral forces and coupler impacts are examined in regards to interaction with wagon lateral and vertical dynamics. Various applications of longitudinal train dynamics are then presented. As an alternative to the tradition single wagon mass approach to longitudinal train dynamics, an example incorporating fully detailed wagon dynamics is presented for a crash analysis problem. Further applications of starting traction, air braking, distributed power, energy analysis and tippler operation are also presented.

Upper-extremity phocomelia reexamined: a longitudinal dysplasia.

Science.gov (United States)

Goldfarb, Charles A; Manske, Paul R; Busa, Riccardo; Mills, Janith; Carter, Peter; Ezaki, Marybeth

2005-12-01

In contrast to longitudinal deficiencies, phocomelia is considered a transverse, intercalated segmental dysplasia. Most patients demonstrate severe, but not otherwise classifiable, upper-extremity deformities, which usually cannot be placed into one of three previously described phocomelia groups. Additionally, these phocomelic extremities do not demonstrate true segmental deficits; the limb is also abnormal proximal and distal to the segmental defect. The purpose of this investigation was to present evidence that upper-extremity abnormalities in patients previously diagnosed as having phocomelia in fact represent a proximal continuum of radial or ulnar longitudinal dysplasia. The charts and radiographs of forty-one patients (sixty extremities) diagnosed as having upper-extremity phocomelia were reviewed retrospectively. On the basis of the findings on the radiographs, the disorders were categorized into three groups: (1) proximal radial longitudinal dysplasia, which was characterized by an absent proximal part of the humerus, a nearly normal distal part of the humerus, a completely absent radius, and a radial-sided hand dysplasia; (2) proximal ulnar longitudinal dysplasia, characterized by a short one-bone upper extremity that bifurcated distally and by severe hand abnormalities compatible with ulnar dysplasia; and (3) severe combined dysplasia, with type A characterized by an absence of the forearm segment (i.e., the radius and ulna) and type B characterized by absence of the arm and forearm (i.e., the hand attached to the thorax). Twenty-nine limbs in sixteen patients could be classified as having proximal radial longitudinal dysplasia. Systemic medical conditions such as thrombocytopenia-absent radius syndrome were common in those patients, but additional musculoskeletal conditions were rare. Twenty limbs in seventeen patients could be classified as having proximal ulnar longitudinal dysplasia. Associated musculoskeletal abnormalities, such as proximal femoral

Sequential Progressions in a Theory of Mind Scale: Longitudinal Perspectives

Science.gov (United States)

Wellman, Henry M.; Fuxi, Fang; Peterson, Candida C.

2011-01-01

Consecutive re-testings of 92 U.S. preschoolers (n = 30), Chinese preschoolers (n = 31), and deaf children (n = 31) examined whether the sequences of development apparent in cross-sectional results with a theory-of-mind scale also appeared in longitudinal assessment. Longitudinal data confirmed that theory-of-mind progressions apparent in cross-sectional scaling data also characterized longitudinal sequences of understanding for individual children. The match between cross-sectional and longitudinal sequences appeared for children who exhibit different progressions across cultures (U.S. vs. China) and for children with substantial delays (deaf children of hearing parents). Moreover, greater scale distances reflected larger longitudinal age differences. PMID:21428982

Requirements for longitudinal HOM damping in superconducting recirculating linacs

International Nuclear Information System (INIS)

Bisognano, J.J.; Fripp, M.L.

1989-01-01

Transverse beam breakup provides the primary current limitation in the operation of superconducting recirculating linacs and requires the significant damping of transverse-deflecting higher order modes. The need to damp the coexisting longitudinal HOMs in these nominally isochronous machines, however, is not as clear. Isochronicity implies that energy variations induced by excitation of longitudinal modes do not translate directly into position and current modulations. Such modulations, if present, could enhance the initial excitation, effectively closing a potentially unstable feedback loop. Design optimization of cavity structures may suggest that no longitudinal damping be provided. On the other hand, easing of the isochronicity requirement may provide desired flexibility in lattice design. In this note, limits are placed on the requirements for longitudinal HOM damping and on the tolerances for isochronicity which are driven by possible longitudinal multipass phenomena. 2 refs., 1 fig

Effect of loading pattern on longitudinal bowing in flexible roll forming

Energy Technology Data Exchange (ETDEWEB)

Kim, Jae Hyun; Woo, Young Yun; Hwang, Tae Woo; Han, Sang Wook; Moon, Young Hoon [School of Mechanical Engineering, Engineering Research Center for Net Shape and Die Manufacturing, Pusan National University,Busan (Korea, Republic of)

2016-12-15

The flexible roll forming process can be used to fabricate products with a variable cross-section profile in the longitudinal direction. Transversal nonuniformity of the longitudinal strain is one of the fundamental characteristics of blank deformation in flexible roll forming. Longitudinal bowing is a shape defect caused by transversal nonuniformity of the longitudinal strain. In this study, loading patterns in flexible roll forming are investigated in order to reduce the longitudinal bowing in a roll-formed blank. To analyze the effects of loading patterns on longitudinal bowing, two different forming schedules are implemented. In schedule 1, loading patterns with different bending angle increments are designed under fixed initial and final bending angles. In schedule 2, loading patterns with different initial bending angles under the fixed final bending angle are designed. Our results show that the bowing heights are significantly affected by the loading patterns. The bowing susceptibilities vary with blank shape such as trapezoid, convex, and concave shapes. In addition to the peak longitudinal strain at the respective roll stands, the cumulative longitudinal strain from the initial to final stands is shown to be a reliable index in predicting the tendency of longitudinal bowing.

College Women's Female Friendships: A Longitudinal View

Science.gov (United States)

Aleman, Ana M. Martinez

2010-01-01

This article presents a longitudinal qualitative study of the cognitive value of female friendships formed in college and seeks to appraise the meaning of the phenomenon for the participants. To grasp the temporal effects of the longitudinal data in this study, the author examines and assesses the relevant developmental literature, particularly…

14 CFR 23.173 - Static longitudinal stability.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Static longitudinal stability. 23.173... Stability § 23.173 Static longitudinal stability. Under the conditions specified in § 23.175 and with the airplane trimmed as indicated, the characteristics of the elevator control forces and the friction within...

The dorsal tectal longitudinal column (TLCd): a second longitudinal column in the paramedian region of the midbrain tectum.

Science.gov (United States)

Aparicio, M-Auxiliadora; Saldaña, Enrique

2014-03-01

The tectal longitudinal column (TLC) is a longitudinally oriented, long and narrow nucleus that spans the paramedian region of the midbrain tectum of a large variety of mammals (Saldaña et al. in J Neurosci 27:13108-13116, 2007). Recent analysis of the organization of this region revealed another novel nucleus located immediately dorsal, and parallel, to the TLC. Because the name "tectal longitudinal column" also seems appropriate for this novel nucleus, we suggest the TLC described in 2007 be renamed the "ventral tectal longitudinal column (TLCv)", and the newly discovered nucleus termed the "dorsal tectal longitudinal column (TLCd)". This work represents the first characterization of the rat TLCd. A constellation of anatomical techniques was used to demonstrate that the TLCd differs from its surrounding structures (TLCv and superior colliculus) cytoarchitecturally, myeloarchitecturally, neurochemically and hodologically. The distinct expression of vesicular amino acid transporters suggests that TLCd neurons are GABAergic. The TLCd receives major projections from various areas of the cerebral cortex (secondary visual mediomedial area, and granular and dysgranular retrosplenial cortices) and from the medial pretectal nucleus. It densely innervates the ipsilateral lateral posterior and laterodorsal nuclei of the thalamus. Thus, the TLCd is connected with vision-related neural centers. The TLCd may be unique as it constitutes the only known nucleus made of GABAergic neurons dedicated to providing massive inhibition to higher order thalamic nuclei of a specific sensory modality.

Hydrologically complemented deterministic slope stability analysis in part of Indian Lesser Himalaya

Directory of Open Access Journals (Sweden)

John Mathew

2016-09-01

Full Text Available This study uses a deterministic approach to evaluate the factor of safety (FS of the terrain for different hydrological conditions, in part of Indian Lesser Himalaya. The results indicate sudden increase in the percentage unstable area from 7.5% to 13.8% for rainfall intensity variation from 50 to 100 mm/day. For the rainfall intensity of 15 August 2007 which caused many landslides in the study area, 18.5% of the total area was unstable and it increases to 21.7%, 23.5% and 24.7%, respectively, for rainfall intensities corresponding to 10, 25 and 50 year return periods. This increment stagnates at about 260 mm/day, making about 25% of the area unstable. Higher rainfall intensities make progressively gentler slopes unstable, but limited to 25 degrees of slope in this area. The area underlain by granitic gneiss showed 23.1% of area as unstable for 135 mm/day of rainfall intensity, and was followed by those areas underlain by amphibolite (16%, limestone (13.7% and quartzite (10.4%. Receiver operating characteristic (ROC curve analysis has given 84.2% accuracy for the model. Conversion of FS to failure probability through Z scores enables identification unstable or marginally unstable areas, for planning selective slope stabilization measures.

Variable selection and estimation for longitudinal survey data

KAUST Repository

Wang, Li; Wang, Suojin; Wang, Guannan

2014-01-01

There is wide interest in studying longitudinal surveys where sample subjects are observed successively over time. Longitudinal surveys have been used in many areas today, for example, in the health and social sciences, to explore relationships

The Role of Microsimulation in Longitudinal Data Analysis

Directory of Open Access Journals (Sweden)

Douglas A. Wolf

2001-12-01

microsimulation also has the potential to contribute to longitudinal data analysis in several ways, including extending the range of outputs generated by a model, addressing several defective-data problems, and serving as a vehicle for missing-data imputation. This paper discusses microsimulation procedures suitable for several commonly-used statistical models applied to longitudinal data. It also addresses the unique role that can be played by microsimulation in longitudinal data analysis, and the problem of accounting for the several sources of variability associated with microsimulation procedures.

Longitudinal dynamics in storage rings

International Nuclear Information System (INIS)

Colton, E.P.

1986-01-01

The single-particle equations of motion are derived for charged particles in a storage ring. Longitudinal space charge is included in the potential assuming an infinitely conducting circular beam pipe with a distributed inductance. The framework uses Hamilton's equations with the canonical variables phi and W. The Twiss parameters for longitudinal motion are also defined for the small amplitude synchrotron oscillations. The space-charge Hamiltonian is calculated for both parabolic bunches and ''matched'' bunches. A brief analysis including second-harmonic rf contributions is also given. The final sections supply calculations of dynamical quantities and particle simulations with the space-charge effects neglected

Passive longitudinal phase space linearizer

Directory of Open Access Journals (Sweden)

P. Craievich

2010-03-01

Full Text Available We report on the possibility to passively linearize the bunch compression process in electron linacs for the next generation x-ray free electron lasers. This can be done by using the monopole wakefields in a dielectric-lined waveguide. The optimum longitudinal voltage loss over the length of the bunch is calculated in order to compensate both the second-order rf time curvature and the second-order momentum compaction terms. Thus, the longitudinal phase space after the compression process is linearized up to a fourth-order term introduced by the convolution between the bunch and the monopole wake function.

Predictive MRI correlates of lesser metatarsophalangeal joint plantar plate tear

Energy Technology Data Exchange (ETDEWEB)

Umans, Rachel L. [Cornell University Medical College, New York, NY (United States); Umans, Benjamin D. [Harvard University, Cambridge, MA (United States); Umans, Hilary [Albert Einstein College of Medicine, Bronx, NY (United States); Lenox Hill Radiology and Imaging Associates, New York, NY (United States); Elsinger, Elisabeth [Albert Einstein College of Medicine, Bronx, NY (United States); Montefiore Medical Center, Bronx, NY (United States)

2016-07-15

To identify correlated signs on non-enhanced MRI that might improve diagnostic detection of plantar plate (PP) tear. We performed an IRB-approved, HIPAA-compliant retrospective analysis of 100 non-contrast MRI (50 PP tear, 50 controls). All were anonymized, randomized, and reviewed; 20 were duplicated to assess consistency. One musculoskeletal radiologist evaluated qualitative variables. A trained non-physician performed measurements. Consistency and concordance were assessed. Pearson's Chi-square test was used to test the correlation between qualitative findings and PP tear status. Correlation between measurements and PP status was assessed using t tests and Wilcoxon's rank-sum test (p values < 0.05 considered significant). Classification and regression trees were utilized to identify attributes that, taken together, would consistently distinguish PP tear from controls. Quantitative measurements were highly reproducible (concordance 0.88-0.99). Elevated 2nd MT protrusion, lesser MT supination and rotational divergence of >45 between the 1st-2nd MT axis correlated with PP tear. Pericapsular soft tissue thickening correlated most strongly with PP tear, correctly classifying 95 % of cases and controls. Excluding pericapsular soft tissue thickening, sequential assessment of 2nd toe enthesitis, 2nd flexor tendon subluxation, and splaying of the second and third toes accurately classified PP status in 92 %. Pericapsular soft tissue thickening most strongly correlated with PP tear. For cases in which it might be difficult to distinguish pericapsular fibrosis from neuroma, sequential assessment of 2nd toe enthesitis, flexor tendon subluxation and splaying of the 2nd and 3rd toe is most helpful for optimizing accurate diagnosis of PP tear. (orig.)

Intercontinental gene flow among western arctic populations of Lesser Snow Geese

Science.gov (United States)

Shorey, Rainy I.; Scribner, Kim T.; Kanefsky, Jeannette; Samuel, Michael D.; Libants, Scot V.

2011-01-01

Quantifying the spatial genetic structure of highly vagile species of birds is important in predicting their degree of population demographic and genetic independence during changing environmental conditions, and in assessing their abundance and distribution. In the western Arctic, Lesser Snow Geese (Chen caerulescens caerulescens) provide an example useful for evaluating spatial population genetic structure and the relative contribution of male and female philopatry to breeding and wintering locales. We analyzed biparentally inherited microsatellite loci and maternally inherited mtDNA sequences from geese breeding at Wrangel Island (Russia) and Banks Island (Canada) to estimate gene flow among populations whose geographic overlap during breeding and winter differ. Significant differences in the frequencies of mtDNA haplotypes contrast with the homogeneity of allele frequencies for microsatellite loci. Coalescence simulations revealed high variability and asymmetry between males and females in rates and direction of gene flow between populations. Our results highlight the importance of wintering areas to demographic independence and spatial genetic structure of these populations. Male-mediated gene flow among the populations on northern Wrangel Island, southern Wrangel Island, and Banks Island has been substantial. A high rate of female-mediated gene flow from southern Wrangel Island to Banks Island suggests that population exchange can be achieved when populations winter in a common area. Conversely, when birds from different breeding populations do not share a common wintering area, the probability of population exchange is likely to be dramatically reduced.

Abundance and density of lesser prairie-chickens and leks in Texas

Science.gov (United States)

Timmer, Jennifer M.; Butler, M.J.; Ballard, Warren; Boal, Clint W.; Whitlaw, Heather A.

2013-01-01

Lesser prairie-chickens (LEPCs; Tympanuchus pallidicinctus) have experienced population declines due to both direct and indirect habitat loss, including conversion of native rangeland to cropland and disturbance from energy development. Our objectives were to 1) determine the current density of LEPC leks and LEPCs within the Texas (USA) occupied range, including areas with high potential for wind-energy development; and 2) find new leks. To estimate lek and LEPC density, we employed a line-transect-based aerial survey method using a Robinson 22 helicopter to count leks. We surveyed 26,810.9 km of transect in the spring of 2010 and 2011 and we detected 96 leks. We estimated a density of 2.0 leks/100 km(2) (90% CI = 1.4-2.7 leks/100 km(2)) and 12.3 LEPCs/100 km(2) (90% CI = 8.5-17.9 LEPCs/100 km(2)) and an abundance of 293.6 leks (90% CI = 213.9-403.0 leks) and 1,822.4 LEPCs (90% CI = 1,253.7-2,649.1 LEPCs) for our sampling frame. Our best model indicated that lek size and lek type (AIC(c) wt = 0.235) influenced lek detectability. Lek detectability was greater for larger leks and natural leks versus man-made leks. Our statewide survey efforts provide wildlife managers and biologists with population estimates, new lek locations, and areas to target for monitoring and conservation.

Longitudinal Electroproduction of Charged Pions from

International Nuclear Information System (INIS)

David Gaskell; Abdellah Ahmidouch; Pawel Ambrozewicz; H. Anklin; John Arrington; K. Assamagan; Steven Avery; Kevin Bailey; Oliver K. Baker; Shelton Beedoe; Elizabeth Beise; Herbert Breuer; D. S. Brown; Roger Carlini; Jinseok Cha; Nicholas Chant; Anthony Cowley; Samuel Danagoulian; D. De Schepper; Jim Dunne; Dipangkar Dutta; Rolf Ent; Liping Gan; Ashot Gasparian; Donald Geesaman; Ron Gilman; Charles Glashausser; Paul Gueye; M. Harvey; O. Hashimoto; Wendy Hinton; G. Hofman; Ceasar Jackson; Hal Jackson; Cynthia Keppel; Ed Kinney; Doug Koltenuk; G. Kyle; Allison Lung; David Mack; D. McKee; Joseph Mitchell; Hamlet Mkrtchyan; B. Mueller; Gabriel Niculescu; Ioana Niculescu; Tom O'Neill; V. Papavassiliou; Dave Potterveld; Juerg Reinhold; Philip Roos; Reyad Sawafta; Ralph Segel; Stepan Stepanyan; Vardan Tadevosyan; T. Takahashi; Liguang Tang; B. Terburg; D. Van Westrum; J. Volmer; T. P. Welch; Stephen Wood; Lulin Yuan; Ben Zeidman; Beni Zihlmann

2001-01-01

Separated longitudinal and transverse cross sections for charged pion electroproduction from 1 H, 2 H, and 3 He were measured at Q 2 = 0.4 (GeV/c) 2 for two values of the invariant mass, (bar W) = 1.15 GeV and (bar W) = 1.60 GeV, in a search for a mass dependence which would signal the effect of nuclear pions. This is the first such study that includes recoil momenta significantly above the Fermi surface. The longitudinal cross section, if dominated by the pion-pole process, should be sensitive to nuclear pion currents. Comparisons of the longitudinal cross section target ratios to a quasifree calculation reveal a significant suppression in 3> He at (bar W) = 1.60 GeV. The (bar W) = 1.15 GeV results are consistent with simple estimates of the effect of nuclear pion currents, but are also consistent with pure quasifree production

Subjective social status and mortality: the English Longitudinal Study of Ageing.

Science.gov (United States)

Demakakos, Panayotes; Biddulph, Jane P; de Oliveira, Cesar; Tsakos, Georgios; Marmot, Michael G

2018-05-19

Self-perceptions of own social position are potentially a key aspect of socioeconomic inequalities in health, but their association with mortality remains poorly understood. We examined whether subjective social status (SSS), a measure of the self-perceived element of social position, was associated with mortality and its role in the associations between objective socioeconomic position (SEP) measures and mortality. We used Cox regression to model the associations between SSS, objective SEP measures and mortality in a sample of 9972 people aged ≥ 50 years from the English Longitudinal Study of Ageing over a 10-year follow-up (2002-2013). Our findings indicate that SSS was associated with all-cause, cardiovascular, cancer and other mortality. A unit decrease in the 10-point continuous SSS measure increased by 24 and 8% the mortality risk of people aged 50-64 and ≥ 65 years, respectively, after adjustment for age, sex and marital status. The respective estimates for cardiovascular mortality were 36 and 11%. Adjustment for all covariates fully explained the association between SSS and cancer mortality, and partially the remaining associations. In people aged 50-64 years, SSS mediated to a varying extent the associations between objective SEP measures and all-cause mortality. In people aged ≥ 65 years, SSS mediated to a lesser extent these associations, and to some extent was associated with mortality independent of objective SEP measures. Nevertheless, in both age groups, wealth partially explained the association between SSS and mortality. In conclusion, SSS is a strong predictor of mortality at older ages, but its role in socioeconomic inequalities in mortality appears to be complex.

Longitudinal Muscle Dysfunction in Achalasia Esophagus and Its Relevance

OpenAIRE

Mittal, Ravinder K; Hong, Su Jin; Bhargava, Valmik

2013-01-01

Muscularis propria of the esophagus is organized into circular and longitudinal muscle layers. Goal of this review is to summarize the role of longitudinal muscle in physiology and pathophysiology of esophageal sensory and motor function. Simultaneous manometry and ultrasound imaging that measure circular and longitudinal muscle contraction respectively reveal that during peristalsis 2 layers of the esophagus contract in perfect synchrony. On the other hand, during transient relaxation of the...

Taxonomic diversity dynamics of early cretaceous brachiopods and gastropods in the Azerbaijanian domains of the Lesser Caucasus (Neo-Tethys Ocean

Directory of Open Access Journals (Sweden)

Ruban Dmitry A.

2014-01-01

Full Text Available Palaeontological data available from the Azerbaijanian domains (Somkhit-Agdam, Sevan-Karabakh, and Miskhan-Kafan tectonic zones of the Lesser Caucasus permit reconstruction of the regional taxonomic diversity dynamics of two groups of Early Cretaceous marine benthic invertebrates. Stratigraphical ranges of 31 species and 14 genera of brachiopods and 40 species and 31 genera of gastropods are considered. The total number of species and genera of brachiopods was low in the Berriasian-Valanginian and then rose to peak in the Barremian. Then, the diversity declined in the Aptian, and brachiopods are not known regionally from the Albian. Gastropods appeared in the Hauterivian and experienced a strong radiation in the Barremian. The diversity of species and genera declined in the Aptian (with a minor radiation in the Middle Aptian, and no gastropods are reported from the Albian. Globally, the number of brachiopod genera remained stable through the Early Cretaceous, and the number of gastropod genera increased stepwise with the maximum in the Albian. The regional and global patterns of the diversity dynamics differed for the both groups of marine benthic invertebrates. The Barremian maximum of the taxonomic diversity coincided with the regional flourishing of reefal ecosystems. The taxonomic diversity dynamics of brachiopods in the Azerbaijanian domains of the Lesser Caucasus is very similar to those of the Northern Caucasus, which is an evidence of proximity of these regions during the Early Cretaceous.

Raptor community composition in the Texas Southern High Plains lesser prairie-chicken range

Science.gov (United States)

Behney, A.C.; Boal, Clint W.; Whitlaw, Heather A.; Lucia, D.R.

2012-01-01

Predation can be a factor in preventing prey population growth and sustainability when prey populations are small and fragmented, and when predator density is unrelated to the density of the single prey species. We conducted monthly raptor surveys from February 2007 to May 2009 in adjacent areas of the Texas Southern High Plains (USA) that do and do not support lesser prairie-chickens (Tympanuchus pallidicinctus), a candidate for protection under the Endangered Species Act. During the summer period corresponding to prairie-chicken nesting and brood-rearing, Swainson's hawks (Buteo swainsoni) were the most abundant raptor. During the lekking and overwintering period, the raptor community was diverse, with northern harriers (Circus cyaneus) being the most abundant species. Raptor abundance peaked during the early autumn and was lowest during the spring. Utility poles were a significant predictor of raptor density at survey points and Swainson's hawks and all raptors, pooled, were found in greater densities in non-prairie-chicken habitat dominated by mesquite (Prosopis glandulosa). Avian predation risk on prairie-chickens, based on presence and abundance of raptors, appears to be greatest during winter when there is a more abundant and diverse raptor community, and in areas with utility poles.

Heat production: Longitudinal versus torsional phacoemulsification.

Science.gov (United States)

Han, Young Keun; Miller, Kevin M

2009-10-01

To compare the heat production of longitudinal versus torsional phacoemulsification under strict laboratory test conditions. Department of Ophthalmology, David Geffen School of Medicine at UCLA, and Jules Stein Eye Institute, Los Angeles, California, USA. Two Infiniti phacoemulsification handpieces were inserted into silicone test chambers filled with a balanced salt solution and imaged serially using a thermal camera. Incision compression was simulated by suspending 25.3 g weights from the silicone chambers. To simulate occlusion of the phacoemulsification tip, the aspiration line was clamped. Peak temperatures were measured 0, 10, 30, 60, and 120 seconds after the commencement of continuous ultrasound power. The 2 handpieces, operating exclusively in longitudinal or torsional modes, were compared 3 ways: (1) using the same power displayed on the instrument console, (2) using identical stroke lengths, and (3) using the same applied energy, a product of stroke length and frequency. For all 3 comparisons, torsional phacoemulsification resulted in lower temperatures at each time point. At the same displayed power setting, the scenario most familiar to cataract surgeons, longitudinal phacoemulsification elevated temperatures up to 41.5 degrees C more than torsional phacoemulsification. Torsional phacoemulsification generated less heat than longitudinal phacoemulsification in all 3 comparison tests. Lower operating temperatures indicate lower heat generation within the same volume of fluid, and this may provide additional thermal protection during cataract surgery.

3-D Magnetotelluric Investigations for geothermal exploration in Martinique (Lesser Antilles). Characteristic Deep Resistivity Structures, and Shallow Resistivity Distribution Matching Heliborne TEM Results

OpenAIRE

Coppo , Nicolas; Baltassat , Jean-Michel; Girard , Jean-François; Wawrzyniak , Pierre; Hautot , Sophie; Tarits , Pascal; Jacob , Thomas; Martelet , Guillaume; Mathieu , Francis; Gadalia , Alain; Bouchot , Vincent; Traineau , Hervé

2015-01-01

International audience; Within the framework of a global French program oriented towards the development of renewable energies, Martinique Island (Lesser Antilles, France) has been extensively investigated (from 2012 to 2013) through an integrated multi-methods approach, with the aim to define precisely the potential geothermal ressources, previously highlighted (Sanjuan et al., 2003). Amongst the common investigation methods deployed, we carried out three magnetotelluric (MT) surveys located...

Oral exposure to dibutyl phthalate exacerbates chronic lymphocytic thyroiditis through oxidative stress in female Wistar rats.

Science.gov (United States)

Wu, Yang; Li, Jinquan; Yan, Biao; Zhu, Yuqing; Liu, Xudong; Chen, Mingqing; Li, Dai; Lee, Ching-Chang; Yang, Xu; Ma, Ping

2017-11-13

Chronic lymphocytic thyroiditis (CLT) is a common autoimmune disorder. The possible pathogenic role and mechanism of dibutyl phthalate (DBP) in CLT is still controversial. Experiments were conducted after 35-days of oral exposure to the three concentrations of DBP or saline, and three immunizations with thyroglobulin (TG). Healthy female Wistar rats were randomly divided into ten exposure groups (n = 8 each): (A) saline control, (B) 0.5 mg/kg/d DBP, (C) 5 mg/kg/d DBP, (D) 50 mg/kg/d DBP, (E) TG-immunized group, (F) TG- combined with 0.5 mg/kg/d DBP, (G) TG- combined with 5 mg/kg/d DBP, (H) TG- combined with 50 mg/kg/d DBP, (I) TG- combined with 50 mg/kg/d DBP plus 100 mg/kg/d vitamin C; (J) 100 mg/kg/d vitamin C. We showed that oral exposure DBP can aggravate CLT in rats. This deterioration was concomitant with increased thyroid auto antibodies, Th1/Th2 imbalance and Th17 immune response, activated pro-inflammatory and apoptosis pathways, and increased thyroid dysfunction in rats. Our results also suggested that DBP could promote oxidative damage. The study also found that vitamin C reduced the levels of oxidative stress and alleviated CLT. In short, the study showed that DBP exacerbated CLT through oxidative stress.

Hypertension awareness and control among young adults in the national longitudinal study of adolescent health.

Science.gov (United States)

Gooding, Holly C; McGinty, Shannon; Richmond, Tracy K; Gillman, Matthew W; Field, Alison E

2014-08-01

Young adults are less likely than older adults to be aware they have hypertension or to be treated for hypertension. To describe rates of hypertension awareness and control in a cohort of young adults and understand the impact of health insurance, utilization of preventive care, and self-perception of health on rates of hypertension awareness and control in this age group. Cross-sectional study of 13,512 young adults participating in Wave IV of the National Longitudinal Study of Adolescent Health in 2007-2008. We defined hypertension as an average of two measured systolic blood pressures (SBP) ≥ 140 mmHg, diastolic blood pressures (DBP) ≥ 90 mmHg, or self-report of hypertension. We defined hypertension awareness as reporting having been told by a health care provider that one had high blood pressure, and assessed awareness among those with uncontrolled hypertension. We considered those aware of having hypertension controlled if their average measured SBP was young adults with hypertension, 2,531 (76%) were uncontrolled, and 1,893 (75%) of those with uncontrolled hypertension were unaware they had hypertension. After adjustment for age, sex, race/ethnicity, weight status, income, education, alcohol and tobacco use, young adults with uncontrolled hypertension who had (vs. didn't have) routine preventive care in the past 2 years were 2.4 times more likely (95% confidence interval [CI] 1.68-3.55) to be aware, but young adults who believed they were in excellent (vs. less than excellent) health were 64% less likely to be aware they had hypertension (OR 0.36, 95% CI 0.23-0.57). Neither preventive care utilization nor self-rated health was associated with blood pressure control. In this nationally representative group of young adults, rates of hypertension awareness and control were low. Efforts to increase detection of hypertension must address young adults' access to preventive care and perception of their need for care.

Longitudinal magnetoresistance and magnototermopower in Bi nanowires

International Nuclear Information System (INIS)

Para, G.

2011-01-01

Full text: The galvanomagnetic effect of single crystals Bi nanowires have been studied in longitudinal magnetic fields up to 14 T. The influence of diameters, temperature and deformation extension on the longitudinal magnetoresistance and magnetotermopower (H||I, H||ΔT) of bismuth nanowires is studied. Elastic deformation measurements were conducted at maximum relative elongation 2 %. For the first time have been investigated the magnetotermopower of Bi nanowires with d=45 nm. Essentially non monotonic dependence H max on temperature in longitudinal thermopower in wires with d=45-60 nm is found out. Such difference in behavior of maximum on R(H) and on α(H) in wires with d<100nm says that the behavior of resistance is caused by other mechanism, then thermopower. (author)

Sources of Self-Efficacy in Academic Contexts: A Longitudinal Perspective

Science.gov (United States)

Phan, Huy P.; Ngu, Bing H.

2016-01-01

The formation of self-efficacy, according to Bandura's (1997) social-cognitive theory, is an important area of inquiry. This theoretical tenet posits the importance of enactive learning experience, followed by lesser influences of vicarious experience, verbal persuasion, and emotional and physiological states. Quantitative research, predominantly,…

Impact of age on the importance of systolic and diastolic blood pressures for stroke risk: the MOnica, Risk, Genetics, Archiving, and Monograph (MORGAM) Project.

Science.gov (United States)

Vishram, Julie K K; Borglykke, Anders; Andreasen, Anne H; Jeppesen, Jørgen; Ibsen, Hans; Jørgensen, Torben; Broda, Grazyna; Palmieri, Luigi; Giampaoli, Simona; Donfrancesco, Chiara; Kee, Frank; Mancia, Giuseppe; Cesana, Giancarlo; Kuulasmaa, Kari; Sans, Susana; Olsen, Michael H

2012-11-01

This study investigates age-related shifts in the relative importance of systolic (SBP) and diastolic (DBP) blood pressures as predictors of stroke and whether these relations are influenced by other cardiovascular risk factors. Using 34 European cohorts from the MOnica, Risk, Genetics, Archiving, and Monograph (MORGAM) Project with baseline between 1982 and 1997, 68 551 subjects aged 19 to 78 years, without cardiovascular disease and not receiving antihypertensive treatment, were included. During a mean of 13.2 years of follow-up, stroke incidence was 2.8%. Stroke risk was analyzed using hazard ratios per 10-mm Hg/5-mm Hg increase in SBP/DBP by multivariate-adjusted Cox regressions, including SBP and DBP simultaneously. Because of nonlinearity, DBP was analyzed separately for DBP ≥ 71 mm Hg and DBP <71 mm Hg. Stroke risk was associated positively with SBP and DBP ≥ 71 mm Hg (SBP/DBP ≥ 71 mm Hg; hazard ratios: 1.15/1.06 [95% CI: 1.12-1.18/1.03-1.09]) and negatively with DBP <71 mm Hg (0.88[0.79-0.98]). The hazard ratio for DBP decreased with age (P<0.001) and was not influenced by other cardiovascular risk factors. Taking into account the age × DBP interaction, both SBP and DBP ≥ 71 mm Hg were significantly associated with stroke risk until age 62 years, but in subjects older than 46 years the superiority of SBP for stroke risk exceeded that of DBP ≥ 71 mm Hg and remained significant until age 78 years. DBP <71 mm Hg became significant at age 50 years with an inverse relation to stroke risk. In Europeans, stroke risk should be assessed by both SBP and DBP until age 62 years with increased focus on SBP from age 47 years. From age 62 years, emphasis should be on SBP without neglecting the potential harm of very low DBP.

Longitudinal Electron Bunch Diagnostics Using Coherent Transition Radiation

CERN Document Server

Mihalcea, Daniel; Happek, Uwe; Regis-Guy Piot, Philippe

2005-01-01

The longitudinal charge distribution of electron bunches in the Fermilab A0 photo-injector was determined by using the coherent transition radiation produced by electrons passing through a thin metallic foil. The auto-correlation of the transition radiation signal was measured with a Michelson type interferometer. The response function of the interferometer was determined from measured and simulated power spectra for low electron bunch charge and maximum longitudinal compression. Kramers-Kroning technique was used to determine longitudinal charge distribution. Measurements were performed for electron bunch lengths in the range from 0.3 to 2 ps (rms).

Reference values and associated factors for Japanese newborns' blood pressure and pulse rate: the babies' and their parents' longitudinal observation in Suzuki Memorial Hospital on intrauterine period (BOSHI) study.

Science.gov (United States)

Satoh, Michihiro; Inoue, Ryusuke; Tada, Hideko; Hosaka, Miki; Metoki, Hirohito; Asayama, Kei; Murakami, Takahisa; Mano, Nariyasu; Ohkubo, Takayoshi; Yagihashi, Katsuyo; Hoshi, Kazuhiko; Suzuki, Masakuni; Imai, Yutaka

2016-08-01

Currently, normative means and ranges of blood pressure (BP) and pulse rates in Japanese newborns are not available. The objective of the present study was to estimate BP, pulse rate, and their distribution among Japanese newborns. Using oscillometric devices, arm or calf BP and pulse rate levels were obtained from 3148 infants born between 2007 and 2014, consecutively at Suzuki Memorial Hospital, Iwanuma, Japan. Of those, data from 2628 full-term, singleton newborns with BP measured on day 3 after birth were analyzed. Arm SBP/DBP and pulse rate in the reference group (n = 2628) were 70.5 ± 7.4/44.3 ± 6.7 mmHg and 117.3 ± 16.6 bpm, respectively. The 5-95th percentiles were 58-83 mmHg for SBP, 35-57 mmHg for DBP, and 91-145 bpm for pulse rate. Similar values were obtained from calf measurements. In multiple regression analysis, birth weight and spontaneous cephalic delivery were positively and light/deep sleep was inversely associated with higher arm SBP/DBP (P ≤ 0.04), whereas sex, Apgar score, gestational age, and mother's age did not significantly affect BP levels (P ≥ 0.06). Male sex, gestational age, spontaneous cephalic delivery, and light/deep sleep were inversely associated with higher pulse rate (P ≤ 0.02). The present study is the first to show the distributions of Asian newborns' BP levels and pulse rate. The assessment of newborns' BP levels and pulse rate should consider birth weight, gestational age after birth, and actual condition at BP measurement.

Multilevel Cross-Dependent Binary Longitudinal Data

KAUST Repository

Serban, Nicoleta

2013-10-16

We provide insights into new methodology for the analysis of multilevel binary data observed longitudinally, when the repeated longitudinal measurements are correlated. The proposed model is logistic functional regression conditioned on three latent processes describing the within- and between-variability, and describing the cross-dependence of the repeated longitudinal measurements. We estimate the model components without employing mixed-effects modeling but assuming an approximation to the logistic link function. The primary objectives of this article are to highlight the challenges in the estimation of the model components, to compare two approximations to the logistic regression function, linear and exponential, and to discuss their advantages and limitations. The linear approximation is computationally efficient whereas the exponential approximation applies for rare events functional data. Our methods are inspired by and applied to a scientific experiment on spectral backscatter from long range infrared light detection and ranging (LIDAR) data. The models are general and relevant to many new binary functional data sets, with or without dependence between repeated functional measurements.

Previous success and current body condition determine breeding propensity in Lesser Scaup: evidence for the individual heterogeneity hypothesis

Science.gov (United States)

Warren, Jeffrey M.; Cutting, Kyle A.; Takekawa, John Y.; De La Cruz, Susan E. W.; Williams, Tony D.; Koons, David N.

2014-01-01

The decision to breed influences an individual's current and future reproduction, and the proportion of individuals that breed is an important determinant of population dynamics. Age, experience, individual quality, and environmental conditions have all been demonstrated to influence breeding propensity. To elucidate which of these factors exerts the greatest influence on breeding propensity in a temperate waterfowl, we studied female Lesser Scaup (Aythya affinis) breeding in southwestern Montana. Females were captured during the breeding seasons of 2007–2009, and breeding status was determined on the basis of (1) presence of an egg in the oviduct or (2) blood plasma vitellogenin (VTG) levels. Presence on the study site in the previous year, a proxy for adult female success, was determined with stable isotope signatures of a primary feather collected at capture. Overall, 57% of females had evidence of breeding at the time of capture; this increased to 86% for females captured on or after peak nest initiation. Capture date and size-adjusted body condition positively influenced breeding propensity, with a declining body-condition threshold through the breeding season. We did not detect an influence of age on breeding propensity. Drought conditions negatively affected breeding propensity, reducing the proportion of breeding females to 0.85 (SE = 0.05) from 0.94 (SE = 0.03) during normal-water years. A female that was present in the previous breeding season was 5% more likely to breed than a female that was not present then. The positive correlation between age and experience makes it difficult to differentiate the roles of age, experience, and individual quality in reproductive success in vertebrates. Our results indicate that individual quality, as expressed by previous success and current body condition, may be among the most important determinants of breeding propensity in female Lesser Scaup, providing further support for the individual heterogeneity hypothesis.

Fingerprints of transverse and longitudinal coupling between induced open quantum dots in the longitudinal magnetoconductance through antidot lattices

Science.gov (United States)

Ujevic, Sebastian; Mendoza, Michel

2010-07-01

We propose numerical simulations of longitudinal magnetoconductance through a finite antidot lattice located inside an open quantum dot with a magnetic field applied perpendicular to the plane. The system is connected to reservoirs using quantum point contacts. We discuss the relationship between the longitudinal magnetoconductance and the generation of transversal couplings between the induced open quantum dots in the system. The system presents longitudinal magnetoconductance maps with crossovers (between transversal bands) and closings (longitudinal decoupling) of fundamental quantum states related to the open quantum dots induced by the antidot lattice. A relationship is observed between the distribution of antidots and the formed conductance bands, allowing a systematic follow up of the bands as a function of the applied magnetic field and quantum point-contact width. We observed a high conductance intensity [between n and (n+1) quantum of conductance, n=1,2,… ] in the regions of crossover and closing of states. This suggests transversal couplings between the induced open quantum dots of the system that can be modulated by varying both the antidots potential and the quantum point-contact width. A new continuous channel (not expected) is induced by the variation in the contact width and generate Fano resonances in the conductance. These resonances can be manipulated by the applied magnetic field.

Longitudinal data analysis a handbook of modern statistical methods

CERN Document Server

Fitzmaurice, Garrett; Verbeke, Geert; Molenberghs, Geert

2008-01-01

Although many books currently available describe statistical models and methods for analyzing longitudinal data, they do not highlight connections between various research threads in the statistical literature. Responding to this void, Longitudinal Data Analysis provides a clear, comprehensive, and unified overview of state-of-the-art theory and applications. It also focuses on the assorted challenges that arise in analyzing longitudinal data. After discussing historical aspects, leading researchers explore four broad themes: parametric modeling, nonparametric and semiparametric methods, joint

Variable selection and estimation for longitudinal survey data

KAUST Repository

Wang, Li

2014-09-01

There is wide interest in studying longitudinal surveys where sample subjects are observed successively over time. Longitudinal surveys have been used in many areas today, for example, in the health and social sciences, to explore relationships or to identify significant variables in regression settings. This paper develops a general strategy for the model selection problem in longitudinal sample surveys. A survey weighted penalized estimating equation approach is proposed to select significant variables and estimate the coefficients simultaneously. The proposed estimators are design consistent and perform as well as the oracle procedure when the correct submodel was known. The estimating function bootstrap is applied to obtain the standard errors of the estimated parameters with good accuracy. A fast and efficient variable selection algorithm is developed to identify significant variables for complex longitudinal survey data. Simulated examples are illustrated to show the usefulness of the proposed methodology under various model settings and sampling designs. © 2014 Elsevier Inc.

Magnetic field of longitudinal gradient bend

Science.gov (United States)

Aiba, Masamitsu; Böge, Michael; Ehrlichman, Michael; Streun, Andreas

2018-06-01

The longitudinal gradient bend is an effective method for reducing the natural emittance in light sources. It is, however, not a common element. We have analyzed its magnetic field and derived a set of formulae. Based on the derivation, we discuss how to model the longitudinal gradient bend in accelerator codes that are used for designing electron storage rings. Strengths of multipole components can also be evaluated from the formulae, and we investigate the impact of higher order multipole components in a very low emittance lattice.

Boron isotope ratios of surface waters in Guadeloupe, Lesser Antilles

Energy Technology Data Exchange (ETDEWEB)

Louvat, Pascale, E-mail: louvat@ipgp.fr [Geochimie et Cosmochimie, IPGP, Universite Paris Diderot, Sorbonne Paris Cite, UMR 7154 CNRS, 75005 Paris (France); Gaillardet, Jerome; Paris, Guillaume; Dessert, Celine [Geochimie et Cosmochimie, IPGP, Universite Paris Diderot, Sorbonne Paris Cite, UMR 7154 CNRS, 75005 Paris (France)

2011-06-15

Highlights: > Rivers outer of hydrothermal areas have d11B around 40 per mille and [B] of 10-31 {mu}g/L. > Thermal springs have d11B of 8-15 per mille and [B] between 250 and 1000 {mu}g/L. > With Na, SO{sub 4} and Cl, boron shows mixing of rain, low and high-T weathering inputs. > Guadeloupe rivers and thermal springs have d11B 20-40 per mille higher than the local rocks. > Solid-solution fractionation during weathering pathways may explain this gap of d11B. - Abstract: Large variations are reported in the B concentrations and isotopic ratios of river and thermal spring waters in Guadeloupe, Lesser Antilles. Rivers have {delta}{sup 11}B values around 40 per mille and B concentrations lower than 30 {mu}g/L, while thermal springs have {delta}{sup 11}B of 8-15 per mille and B concentrations of 250-1000 {mu}g/L. River samples strongly impacted by hydrothermal inputs have intermediate {delta}{sup 11}B and B contents. None of these surface water samples have {delta}{sup 11}B comparable to the local unweathered volcanic rocks (around 0 per mille), implying that a huge isotopic fractionation of 40 per mille takes place during rock weathering, which could be explained by preferential incorporation of {sup 10}B during secondary mineral formation and adsorption on clays, during rock weathering or in the soils. The soil-vegetation B cycle could also be a cause for such a fractionation. Atmospheric B with {delta}{sup 11}B of 45 per mille represents 25-95% of the river B content. The variety of the thermal spring chemical composition renders the understanding of B behavior in Guadeloupe hydrothermal system quite difficult. Complementary geochemical tracers would be helpful.

Boron isotope ratios of surface waters in Guadeloupe, Lesser Antilles

International Nuclear Information System (INIS)

Louvat, Pascale; Gaillardet, Jerome; Paris, Guillaume; Dessert, Celine

2011-01-01

Highlights: → Rivers outer of hydrothermal areas have d11B around 40 per mille and [B] of 10-31 μg/L. → Thermal springs have d11B of 8-15 per mille and [B] between 250 and 1000 μg/L. → With Na, SO 4 and Cl, boron shows mixing of rain, low and high-T weathering inputs. → Guadeloupe rivers and thermal springs have d11B 20-40 per mille higher than the local rocks. → Solid-solution fractionation during weathering pathways may explain this gap of d11B. - Abstract: Large variations are reported in the B concentrations and isotopic ratios of river and thermal spring waters in Guadeloupe, Lesser Antilles. Rivers have δ 11 B values around 40 per mille and B concentrations lower than 30 μg/L, while thermal springs have δ 11 B of 8-15 per mille and B concentrations of 250-1000 μg/L. River samples strongly impacted by hydrothermal inputs have intermediate δ 11 B and B contents. None of these surface water samples have δ 11 B comparable to the local unweathered volcanic rocks (around 0 per mille), implying that a huge isotopic fractionation of 40 per mille takes place during rock weathering, which could be explained by preferential incorporation of 10 B during secondary mineral formation and adsorption on clays, during rock weathering or in the soils. The soil-vegetation B cycle could also be a cause for such a fractionation. Atmospheric B with δ 11 B of 45 per mille represents 25-95% of the river B content. The variety of the thermal spring chemical composition renders the understanding of B behavior in Guadeloupe hydrothermal system quite difficult. Complementary geochemical tracers would be helpful.

Stratigraphy of the Grande Savane Ignimbrite Sequence, Dominica, Lesser Antilles

Science.gov (United States)

Schneider, S.; Smith, A. L.; Deuerling, K.; Killingsworth, N.; Daly, G.

2007-12-01

The island of Dominica, located in the central part of the Lesser Antilles island arc has eight potentially active volcanoes. One of these, Morne Diablotins, is a composite stratovolcano with several superimposed stratigraphic sequences ranging in age from Pliocene (4-2 Ma) to "Younger" Pleistocene (22,000 and >40,000 years B.P. The ignimbrite sequences form four flow fans that reached both the east and west coasts of the island. One of these flow fans, the Grande Savane, on the west coast of the island, also extends off-shore for a distance of at least 14 km as a distinctive submarine fan. Stratigraphical studies of the on- shore deposits that make up this fan indicate an older sequence of block and ash flow deposits, within which occurs a distinctive vulcanian fall deposit. These are overlain, with no evidence of an intervening paleosol, by a sequence of ignimbrites containing welded horizons (ranging in thickness from around 4 m to 16m). The lack of fall deposits beneath the ignimbrites suggest they may have been formed by instantaneous continuous collapse of the eruption column. This whole succession is overlain by a series of planar and dune bedded pumiceous surge deposits with interbedded pumiceous lapilli fall and ash fall deposits, that extend laterally outside of the main area of ignimbrite deposition. Beds within this upper sequence often contain accretionary lapilli and gas cavities suggesting magma-water interaction. The youngest deposits from Morne Diablotins appear to be valley- fill deposits of both ignimbrite and block and ash flow. A comparison of the of the Grande Savane pyroclastic sequence with the Pointe Ronde (west coast) and Londonderry (east coast) pyroclastic flow fans will provide information on the eruptive history of this major Plinian episode.

Worldwide genetic variability of the Duffy binding protein: insights into Plasmodium vivax vaccine development.

Science.gov (United States)

Nóbrega de Sousa, Taís; Carvalho, Luzia Helena; Alves de Brito, Cristiana Ferreira

2011-01-01

The dependence of Plasmodium vivax on invasion mediated by Duffy binding protein (DBP) makes this protein a prime candidate for development of a vaccine. However, the development of a DBP-based vaccine might be hampered by the high variability of the protein ligand (DBP(II)), known to bias the immune response toward a specific DBP variant. Here, the hypothesis being investigated is that the analysis of the worldwide DBP(II) sequences will allow us to determine the minimum number of haplotypes (MNH) to be included in a DBP-based vaccine of broad coverage. For that, all DBP(II) sequences available were compiled and MNH was based on the most frequent nonsynonymous single nucleotide polymorphisms, the majority mapped on B and T cell epitopes. A preliminary analysis of DBP(II) genetic diversity from eight malaria-endemic countries estimated that a number between two to six DBP haplotypes (17 in total) would target at least 50% of parasite population circulating in each endemic region. Aiming to avoid region-specific haplotypes, we next analyzed the MNH that broadly cover worldwide parasite population. The results demonstrated that seven haplotypes would be required to cover around 60% of DBP(II) sequences available. Trying to validate these selected haplotypes per country, we found that five out of the eight countries will be covered by the MNH (67% of parasite populations, range 48-84%). In addition, to identify related subgroups of DBP(II) sequences we used a Bayesian clustering algorithm. The algorithm grouped all DBP(II) sequences in six populations that were independent of geographic origin, with ancestral populations present in different proportions in each country. In conclusion, in this first attempt to undertake a global analysis about DBP(II) variability, the results suggest that the development of DBP-based vaccine should consider multi-haplotype strategies; otherwise a putative P. vivax vaccine may not target some parasite populations.

Endogenous contributions to egg protein formation in lesser scaup Aythya affinis

Science.gov (United States)

Cutting, Kyle A.; Hobson, Keith A.; Rotella, Jay J.; Warren, Jeffrey M.; Wainwright-de la Cruz, Susan E.; Takekawa, John Y.

2011-01-01

Lesser scaup Aythya affinis populations have declined throughout the North American continent for the last three decades. It has been hypothesized that the loss and degradation of staging habitats has resulted in reduced female body condition on the breeding grounds and a concomitant decline in productivity. We explored the importance of body (endogenous) reserves obtained prior to arrival on the breeding ground in egg protein formation in southwestern Montana during 2006–2008 using stable-carbon (δ13C) and nitrogen (δ15N) isotope analyses of scaup egg components, female tissue, and local prey items. From arrival on the breeding grounds through the egg-laying period, δ15N values of scaup red blood cells decreased while δ13C values became less variable; a pattern consistent with endogenous tissues equilibrating with local (freshwater) dietary sources. In 2006 and 2008, isotopic values for egg albumen and yolk protein indicated that most (>90%) protein used to produce these components was obtained on the breeding grounds. However, in 2007, a year with an exceptionally warm and dry spring, endogenous reserves contributed on average 41% of yolk and 29% of albumen. Results from this study suggest that female scaup can meet the protein needs of egg production largely from local dietary food sources. This highlights the importance of providing high-quality breeding habitats for scaup. Whether this pattern holds in areas with similar breeding season lengths but longer migration routes, such as those found in the western boreal forest, should be investigated.

Dynamics of a longitudinal current during a magnetic storm

International Nuclear Information System (INIS)

Dolginov, S.Sh.; Zhuzgov, L.N.; Kosacheva, V.P.; Strunnikova, L.N.; Tyurmina, L.O.; Sharova, V.A.; Shkol'nikova, S.I.

1984-01-01

Results, investigating a spatial distribution and the structure of longitudinal currents during a magnetic storm at 18-19.09.81, are presented. It is shown that during the main phase of the storm the large-scale current system expands to the equator, and current density increases. Inside the current layer and to the pole of it there appears intensive small scale longitudinal l currents. During magnetic storm restopation phase the current system segregates into several pairs of opposite directed currents. During further decreasing of geomagnetic activity the large-scale current system is restored+ and its center is shifted to the pole, longitudinal current density being decreased. The invariant width of longitudinal currents is decreased, while the magnitude, Dsub(st), being increased, that is connected to the displacement of an auroral oval to the equator

Multi-longitudinal-mode micro-laser model

Science.gov (United States)

Staliunas, Kestutis

2017-10-01

We derive a convenient model for broad aperture micro-lasers, such as microchip lasers, broad area semiconductor lasers, or VCSELs, taking into account several longitudinal mode families. We provide linear stability analysis, and show characteristic spatio-temporal dynamics in such multi-longitudinal mode laser models. Moreover, we derive the coupled mode model in the presence of intracavity refraction index modulation (intracavity photonic crystal). Contribution to the Topical Issue "Theory and Applications of the Lugiato-Lefever Equation", edited by Yanne K. Chembo, Damia Gomila, Mustapha Tlidi, Curtis R. Menyuk.

Longitudinal Risk Factors for Cyberbullying in Adolescence

OpenAIRE

Sticca, Fabio; Ruggieri, Sabrina; Alsaker, Françoise; Perren, Sonja

2013-01-01

Cyberbullying has emerged as a new form of antisocial behaviour in the context of online communication over the last decade. The present study investigates potential longitudinal risk factors for cyberbullying. A total of 835 Swiss seventh graders participated in a short-term longitudinal study (two assessments 6 months apart). Students reported on the frequency of cyberbullying, traditional bullying, rule-breaking behaviour, cybervictimisation, traditional victimisation, and frequency of onl...

Longitudinal Control for Mengshi Autonomous Vehicle via Gauss Cloud Model

Directory of Open Access Journals (Sweden)

Hongbo Gao

2017-12-01

Full Text Available Dynamic robustness and stability control is a requirement for self-driving of autonomous vehicle. Longitudinal control technique of autonomous vehicle is basic theory and one key complex technique which must have the reliability and precision of vehicle controller. The longitudinal control technique is one of the foundations of the safety and stability of autonomous vehicle control. In our paper, we present a longitudinal control algorithm based on cloud model for Mengshi autonomous vehicle to ensure the dynamic stability and tracking performance of Mengshi autonomous vehicle. The longitudinal control algorithm mainly uses cloud model generator to control the acceleration of the autonomous vehicle to achieve the goal that controls the speed of Mengshi autonomous vehicle. The proposed longitudinal control algorithm based on cloud model is verified by real experiments on Highway driving scene. The experiments results of the acceleration and speed show that the algorithm is validity and stability.

Parameterized Linear Longitudinal Airship Model

Science.gov (United States)

Kulczycki, Eric; Elfes, Alberto; Bayard, David; Quadrelli, Marco; Johnson, Joseph

2010-01-01

A parameterized linear mathematical model of the longitudinal dynamics of an airship is undergoing development. This model is intended to be used in designing control systems for future airships that would operate in the atmospheres of Earth and remote planets. Heretofore, the development of linearized models of the longitudinal dynamics of airships has been costly in that it has been necessary to perform extensive flight testing and to use system-identification techniques to construct models that fit the flight-test data. The present model is a generic one that can be relatively easily specialized to approximate the dynamics of specific airships at specific operating points, without need for further system identification, and with significantly less flight testing. The approach taken in the present development is to merge the linearized dynamical equations of an airship with techniques for estimation of aircraft stability derivatives, and to thereby make it possible to construct a linearized dynamical model of the longitudinal dynamics of a specific airship from geometric and aerodynamic data pertaining to that airship. (It is also planned to develop a model of the lateral dynamics by use of the same methods.) All of the aerodynamic data needed to construct the model of a specific airship can be obtained from wind-tunnel testing and computational fluid dynamics

Bayesian Nonparametric Longitudinal Data Analysis.

Science.gov (United States)

Quintana, Fernando A; Johnson, Wesley O; Waetjen, Elaine; Gold, Ellen

2016-01-01

Practical Bayesian nonparametric methods have been developed across a wide variety of contexts. Here, we develop a novel statistical model that generalizes standard mixed models for longitudinal data that include flexible mean functions as well as combined compound symmetry (CS) and autoregressive (AR) covariance structures. AR structure is often specified through the use of a Gaussian process (GP) with covariance functions that allow longitudinal data to be more correlated if they are observed closer in time than if they are observed farther apart. We allow for AR structure by considering a broader class of models that incorporates a Dirichlet Process Mixture (DPM) over the covariance parameters of the GP. We are able to take advantage of modern Bayesian statistical methods in making full predictive inferences and about characteristics of longitudinal profiles and their differences across covariate combinations. We also take advantage of the generality of our model, which provides for estimation of a variety of covariance structures. We observe that models that fail to incorporate CS or AR structure can result in very poor estimation of a covariance or correlation matrix. In our illustration using hormone data observed on women through the menopausal transition, biology dictates the use of a generalized family of sigmoid functions as a model for time trends across subpopulation categories.

Influence of Baseline Diastolic Blood Pressure on Effects of Intensive Compared With Standard Blood Pressure Control.

Science.gov (United States)

Beddhu, Srinivasan; Chertow, Glenn M; Cheung, Alfred K; Cushman, William C; Rahman, Mahboob; Greene, Tom; Wei, Guo; Campbell, Ruth C; Conroy, Margaret; Freedman, Barry I; Haley, William; Horwitz, Edward; Kitzman, Dalane; Lash, James; Papademetriou, Vasilios; Pisoni, Roberto; Riessen, Erik; Rosendorff, Clive; Watnick, Suzanne G; Whittle, Jeffrey; Whelton, Paul K

2018-01-09

In individuals with a low diastolic blood pressure (DBP), the potential benefits or risks of intensive systolic blood pressure (SBP) lowering are unclear. SPRINT (Systolic Blood Pressure Intervention Trial) was a randomized controlled trial that compared the effects of intensive (target baseline DBP. Mean baseline SBP and DBP were 139.7±15.6 and 78.1±11.9 mm Hg, respectively. Regardless of the randomized treatment, baseline DBP had a U-shaped association with the hazard of the primary cardiovascular disease outcome. However, the effects of the intensive SBP intervention on the primary outcome were not influenced by baseline DBP level ( P for interaction=0.83). The primary outcome hazard ratio for intensive versus standard treatment was 0.78 (95% confidence interval, 0.57-1.07) in the lowest DBP quintile (mean baseline DBP, 61±5 mm Hg) and 0.74 (95% confidence interval, 0.61-0.90) in the upper 4 DBP quintiles (mean baseline DBP, 82±9 mm Hg), with an interaction P value of 0.78. Results were similar for all-cause death and kidney events. Low baseline DBP was associated with increased risk of cardiovascular disease events, but there was no evidence that the benefit of the intensive SBP lowering differed by baseline DBP. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01206062. © 2017 American Heart Association, Inc.

A single hole tracer test to determine longitudinal dispersion

International Nuclear Information System (INIS)

Noy, D.J.; Holmes, D.C.

1986-03-01

The paper concerns a single hole tracer test to determine longitudinal dispersion, which is an important parameter in assessing the suitability of a site for radioactive waste disposal. The theory, equipment and procedure for measuring longitudinal dispersion in a single borehole is described. Results are presented for field trials conducted in an aquifer, where the technique produced good results. The measured value of longitudinal dispersion, from a single hole test, relates only to a limited volume of rock immediately adjacent to the borehole. (U.K.)

New Perspective of Tsunami Deposit Investigations: Insight from the 1755 Lisbon Tsunami in Martinique, Lesser Antilles.

Science.gov (United States)

Roger, J.; Clouard, V.; Moizan, E.

2014-12-01

The recent devastating tsunamis having occurred during the last decades have highlighted the essential necessity to deploy operationnal warning systems and educate coastal populations. This could not be prepared correctly without a minimum knowledge about the tsunami history. That is the case of the Lesser Antilles islands, where a few handfuls of tsunamis have been reported over the past 5 centuries, some of them leading to notable destructions and inundations. But the lack of accurate details for most of the historical tsunamis and the limited period during which we could find written information represents an important problem for tsunami hazard assessment in this region. Thus, it is of major necessity to try to find other evidences of past tsunamis by looking for sedimentary deposits. Unfortunately, island tropical environments do not seem to be the best places to keep such deposits burried. In fact, heavy rainfalls, storms, and all other phenomena leading to coastal erosion, and associated to human activities such as intensive sugarcane cultivation in coastal flat lands, could caused the loss of potential tsunami deposits. Lots of places have been accurately investigated within the Lesser Antilles (from Sainte-Lucia to the British Virgin Islands) the last 3 years and nothing convincing has been found. That is when archeaological investigations excavated a 8-cm thick sandy and shelly layer in downtown Fort-de-France (Martinique), wedged between two well-identified layers of human origin (Fig. 1), that we found new hope: this sandy layer has been quickly attributed without any doubt to the 1755 tsunami, using on one hand the information provided by historical reports of the construction sites, and on the other hand by numerical modeling of the tsunami (wave heights, velocity fields, etc.) showing the ability of this transoceanic tsunami to wrap around the island after ~7 hours of propagation, enter Fort-de-France's Bay with enough energy to carry sediments, and

Numerical Tsunami Hazard Assessment of the Only Active Lesser Antilles Arc Submarine Volcano: Kick 'em Jenny.

Science.gov (United States)

Dondin, F. J. Y.; Dorville, J. F. M.; Robertson, R. E. A.

2015-12-01

The Lesser Antilles Volcanic Arc has potentially been hit by prehistorical regional tsunamis generated by voluminous volcanic landslides (volume > 1 km3) among the 53 events recognized so far. No field evidence of these tsunamis are found in the vincity of the sources. Such a scenario taking place nowadays would trigger hazardous tsunami waves bearing potentially catastrophic consequences for the closest islands and regional offshore oil platforms.Here we applied a complete hazard assessment method on the only active submarine volcano of the arc Kick 'em Jenny (KeJ). KeJ is the southernmost edifice with recognized associated volcanic landslide deposits. From the three identified landslide episodes one is associated with a collapse volume ca. 4.4 km3. Numerical simulations considering a single pulse collapse revealed that this episode would have produced a regional tsunami. An edifice current volume estimate is ca. 1.5 km3.Previous study exists in relationship to assessment of regional tsunami hazard related to shoreline surface elevation (run-up) in the case of a potential flank collapse scenario at KeJ. However this assessment was based on inferred volume of collapse material. We aim to firstly quantify potential initial volumes of collapse material using relative slope instability analysis (RSIA); secondly to assess first order run-ups and maximum inland inundation distance for Barbados and Trinidad and Tobago, i.e. two important economic centers of the Lesser Antilles. In this framework we present for seven geomechanical models tested in the RSIA step maps of critical failure surface associated with factor of stability (Fs) for twelve sectors of 30° each; then we introduce maps of expected potential run-ups (run-up × the probability of failure at a sector) at the shoreline.The RSIA evaluates critical potential failure surface associated with Fs <1 as compared to areas of deficit/surplus of mass/volume identified on the volcanic edifice using (VolcanoFit 2

Multiscaling properties of tropical rainfall: Analysis of rain gauge datasets in Lesser Antilles island environment

Science.gov (United States)

Bernard, Didier C.; Pasquier, Raphaël; Cécé, Raphaël; Dorville, Jean-François

2014-05-01

Changes in rainfall seem to be the main impact of climate change in the Caribbean area. The last conclusions of IPCC (2013), indicate that the end of this century will be marked by a rise of extreme rainfalls in tropical areas, linked with increase of the mean surface temperature. Moreover, most of the Lesser Antilles islands are characterized by a complex topography which tends to enhance the rainfall from synoptic disturbances by orographic effects. In the past five years, out of hurricanes passage, several extreme rainy events (approx. 16 mm in 6 minutes), including fatal cases, occurred in the Lesser Antilles Arc: in Guadeloupe (January 2011, May 2012 and 2013), in Martinique (May 2009, April 2011 and 2013), in Saint-Lucia (December 2013). These phenomena inducing floods, loss of life and material damages (agriculture sector and public infrastructures), inhibit the development of the islands. At this time, numerical weather prediction models as WRF, which are based on the equations of the atmospheric physics, do not show great results in the focused area (Bernard et al., 2013). Statistical methods may be used to examine explicitly local rainy updrafts, thermally and orographically induced at micro-scale. The main goal of the present insular tropical study is to characterize the multifractal symmetries occurring in the 6-min rainfall time series, registered since 2006 by the French Met. Office network weather stations. The universal multifractal model (Schertzer and Lovejoy, 1991) is used to define the statistical properties of measured rainfalls at meso-scale and micro-scale. This model is parametrized by a fundamental exponents set (H,a,C1,q) which are determined and compared with values found in the literature. The first three parameters characterize the mean pattern and the last parameter q, the extreme pattern. The occurrence ranges of multifractal regime are examined. The suggested links between the internal variability of the tropical rainy events and the

A DNA Binding Protein Is Required for Viral Replication and Transcription in Bombyx mori Nucleopolyhedrovirus.

Directory of Open Access Journals (Sweden)

Cui Zhao

Full Text Available A DNA-binding protein (DBP [GenBank accession number: M63416] of Bombyx mori nuclear polyhedrosis virus (BmNPV has been reported to be a regulatory factor in BmNPV, but its detailed functions remain unknown. In order to study the regulatory mechanism of DBP on viral proliferation, genome replication, and gene transcription, a BmNPV dbp gene knockout virus dbp-ko-Bacmid was generated by the means of Red recombination system. In addition, dbp-repaired virus dbp-re-Bacmid was constructed by the means of the Bac to Bac system. Then, the Bacmids were transfected into BmN cells. The results of this viral titer experiment revealed that the TCID50 of the dbp-ko-Bacmid was 0; however, the dbp-re-Bacmid was similar to the wtBacmid (p>0.05, indicating that the dbp-deficient would lead to failure in the assembly of virus particles. In the next step, Real-Time PCR was used to analyze the transcriptional phases of dbp gene in BmN cells, which had been infected with BmNPV. The results of the latter experiment revealed that the transcript of dbp gene was first detected at 3 h post-infection. Furthermore, the replication level of virus genome and the transcriptional level of virus early, late, and very late genes in BmN cells, which had been transfected with 3 kinds of Bacmids, were analyzed by Real-Time PCR. The demonstrating that the replication level of genome was lower than that of wtBacmid and dbp-re-Bacmid (p<0.01. The transcriptional level of dbp-ko-Bacmid early gene lef-3, ie-1, dnapol, late gene vp39 and very late gene p10 were statistically significantly lower than dbp-re-Bacmid and wtBacmid (p<0.01. The results presented are based on Western blot analysis, which indicated that the lack of dbp gene would lead to low expressions of lef3, vp39, and p10. In conclusion, dbp was not only essential for early viral replication, but also a viral gene that has a significant impact on transcription and expression during all periods of baculovirus life cycle.

Longitudinal variability of time-location/activity patterns of population at different ages: a longitudinal study in California

Directory of Open Access Journals (Sweden)

Cassady Diana L

2011-09-01

Full Text Available Abstract Background Longitudinal time-activity data are important for exposure modeling, since the extent to which short-term time-activity data represent long-term activity patterns is not well understood. This study was designed to evaluate longitudinal variations in human time-activity patterns. Method We report on 24-hour recall diaries and questionnaires collected via the internet from 151 parents of young children (mostly under age 55, and from 55 older adults of ages 55 and older, for both a weekday and a weekend day every three months over an 18-month period. Parents also provided data for their children. The self-administrated diary and questionnaire distinguished ~30 frequently visited microenvironments and ~20 activities which we selected to represent opportunities for exposure to toxic environmental compounds. Due to the non-normal distribution of time-location/activity data, we employed generalized linear mixed-distribution mixed-effect models to examine intra- and inter-individual variations. Here we describe variation in the likelihood of and time spent engaging in an activity or being in a microenvironment by age group, day-type (weekday/weekend, season (warm/cool, sex, employment status, and over the follow-up period. Results As expected, day-type and season influence time spent in many location and activity categories. Longitudinal changes were also observed, e.g., young children slept less with increasing follow-up, transit time increased, and time spent on working and shopping decreased during the study, possibly related to human physiological changes with age and changes in macro-economic factors such as gas prices and the economic recession. Conclusions This study provides valuable new information about time-activity assessed longitudinally in three major age groups and greatly expands our knowledge about intra- and inter-individual variations in time-location/activity patterns. Longitudinal variations beyond weekly and

Assessments of the lesser sandeel ( Ammodytes marinus ) in the North Sea based on revised stock divisions

DEFF Research Database (Denmark)

Pedersen, S.A.; Lewy, Peter; Wright, P.

1999-01-01

effort, catch per unit effort, yield, fishing and natural mortality. A better understanding of sandeel growth is important for stock and catch predictions because previous studies indicate that the variability of mean weight-at-age is one of the most important factors influencing the precision......Recent investigations suggest that the current treatment of North Sea sandeel (Ammodytes marinus) as a single unit stock may have little biological basis. In order to study regional effects of the fishery on North Sea lesser sandeel it may therefore be important to assess stock dynamics...... of predictions. The Danish weight-at-age data of sandeel are re- analysed to estimate the mean weight-at-age in the catch and the stock and the precision of the estimates. The reliability of the sandeel assessments is discussed in relation to the data sources available and to the knowledge of sandeel biology...

A DNA Binding Protein Is Required for Viral Replication and Transcription in Bombyx mori Nucleopolyhedrovirus.

Science.gov (United States)

Zhao, Cui; Zhang, Chen; Chen, Bin; Shi, Yanghui; Quan, Yanping; Nie, Zuoming; Zhang, Yaozhou; Yu, Wei

2016-01-01

A DNA-binding protein (DBP) [GenBank accession number: M63416] of Bombyx mori nuclear polyhedrosis virus (BmNPV) has been reported to be a regulatory factor in BmNPV, but its detailed functions remain unknown. In order to study the regulatory mechanism of DBP on viral proliferation, genome replication, and gene transcription, a BmNPV dbp gene knockout virus dbp-ko-Bacmid was generated by the means of Red recombination system. In addition, dbp-repaired virus dbp-re-Bacmid was constructed by the means of the Bac to Bac system. Then, the Bacmids were transfected into BmN cells. The results of this viral titer experiment revealed that the TCID50 of the dbp-ko-Bacmid was 0; however, the dbp-re-Bacmid was similar to the wtBacmid (p>0.05), indicating that the dbp-deficient would lead to failure in the assembly of virus particles. In the next step, Real-Time PCR was used to analyze the transcriptional phases of dbp gene in BmN cells, which had been infected with BmNPV. The results of the latter experiment revealed that the transcript of dbp gene was first detected at 3 h post-infection. Furthermore, the replication level of virus genome and the transcriptional level of virus early, late, and very late genes in BmN cells, which had been transfected with 3 kinds of Bacmids, were analyzed by Real-Time PCR. The demonstrating that the replication level of genome was lower than that of wtBacmid and dbp-re-Bacmid (plife cycle.

Degradation of dibutyl phthalate in two contrasting agricultural soils and its long-term effects on soil microbial community.

Science.gov (United States)

Cheng, Jinjin; Liu, Yanai; Wan, Qun; Yuan, Li; Yu, Xiangyang

2018-06-04

Due to its widespread application and large-scale production, dibutyl phthalate (DBP) has become one of the most frequently identified phthalic acid esters (PAEs) in soils. The fate of DBP and its effects on microbial communities in soils with contrasting properties have seldom been studied. In this study, the degradation of DBP and its long-term effects on the soil microbial community were investigated in aquic cambisols and udic ferrosols. The half-lives of DBP in aquic cambisols and udic ferrosols were found to be 0.286-1.41 days and 0.870-20.4 days, respectively, indicating that DBP was degraded faster in aquic cambisols. In addition, the degradation of DBP in aquic cambisols was less vulnerable to adverse incubation conditions, including high DBP concentration, low temperature and low moisture. These results can be ascribed to the higher microbial abundance and activity in aquic cambisols than in udic ferrosols. During DBP degradation, the toxic metabolite monobutyl phthalate (MBP) was present only transiently and did not accumulate in the two soils. After 60 days of incubation, the degradation-resistant DBP residue concentrations were as high as 1.10 and 1.34 mg/kg, and the relative abundance of 8.51%-12.9% of bacterial genera and 5.59%-6.02% of fungal genera was significantly disturbed by DBP in both test soils. The results from this study highlight the need to comprehensively evaluate the environmental risks of degradation-resistant DBP residues and the impact of DBP contamination on soil microbial functions. Copyright © 2018. Published by Elsevier B.V.

Nonlinear longitudinal dynamics studies at the ALS

International Nuclear Information System (INIS)

Byrd, J.M.; Cheng, W.-H.; De Santis, S.; Li, D.; Stupakov, G.; Zimmermann, F.

1999-01-01

We present a summary of results for a variety of studies of nonlinear longitudinal dynamics in the Advanced Light Source, an electron storage ring. These include observation of decoherence at injection, decay of an injected beam, forced synchrotron oscillations and diffusion from one bunch to the next. All of the measurements were made using a dual-scan streak camera which allowed the real-time observation of the longitudinal distribution of the electron beam

A Longitudinal Examination of Childhood Maltreatment and Adolescent Obesity: Results from the National Longitudinal Study of Adolescent Health (AddHealth) Study

Science.gov (United States)

Shin, Sunny Hyucksun; Miller, Daniel P.

2012-01-01

Objectives: We sought to explore the association between childhood maltreatment (e.g., neglect, physical and sexual abuse) and longitudinal growth trajectories of body mass index (BMI) from adolescence to young adulthood. Methods: We used latent curve modeling to examine data from the National Longitudinal Study of Adolescent Health (N = 8,471),…

Signal processing for longitudinal parameters of the Tevatron beam

International Nuclear Information System (INIS)

Pordes, S.; Crisp, J.; Fellenz, B.; Flora, R.; Para, A.; Tollestrup, A.V.

2005-01-01

We describe the system known as the Tevatron SBD [1] which is used to provide information on the longitudinal parameters of coalesced beam bunches in the Tevatron. The system has been upgraded over the past year with a new digitizer and improved software. The quantities provided for each proton and antiproton bunch include the intensity, the longitudinal bunch profile, the timing of the bunch with respect to the low-level RF, the momentum spread and the longitudinal emittance. The system is capable of 2 Hz operation and is run at 1 Hz

Longitudinal-bending mode micromotor using multilayer piezoelectric actuator.

Science.gov (United States)

Yao, K; Koc, B; Uchino, K

2001-07-01

Longitudinal-bending mode ultrasonic motors with a diameter of 3 mm were fabricated using stacked multilayer piezoelectric actuators, which were self-developed from hard lead zirconate titanate (PZT) ceramic. A bending vibration was converted from a longitudinal vibration with a longitudinal-bending coupler. The motors could be bidirectionally operated by changing driving frequency. Their starting and braking torque were analyzed based on the transient velocity response. With a load of moment of inertia 2.5 x 10(-7) kgm2, the motor showed a maximum starting torque of 127.5 microNm. The braking torque proved to be a constant independent on the motor's driving conditions and was roughly equivalent to the maximum starting torque achievable with our micromotors.

The Relationships of Expectancies With E-cigarette Use Among Hospitalized Smokers: A Prospective Longitudinal Study.

Science.gov (United States)

Hendricks, Peter S; Thorne, Christopher B; Lappan, Sara N; Sweat, Noah W; Cheong, JeeWon; Ramachandran, Rekha; Kohler, Connie L; Bailey, William C; Harrington, Kathleen F

2018-01-05

Expectancies demonstrate cross-sectional associations with e-cigarette use, but the prospective relationships between expectancies and e-cigarette use are unknown. This study examined the longitudinal associations of expectancies with e-cigarette use among hospitalized tobacco cigarette smokers. E-cigarette expectancies (e-cigarette-specific Brief Smoking Consequences Questionnaire-Adult [BSCQ-A]), tobacco cigarette expectancies (tobacco-specific BSCQ-A), and number of days used e-cigarettes in the past 30 days were assessed at baseline hospitalization, 6-months post-hospitalization, and 12-months post-hospitalization among 978 hospitalized tobacco cigarette smokers. Expectancy difference scores (e-cigarette-specific expectancies minus tobacco-specific expectancies) were computed for each of the 10 BSCQ-A scales. Cross-lagged panel models tested the relationships between expectancy difference scores and number of days used e-cigarettes in the past 30 days for each of the 10 BSCQ-A scales. Though some models revealed partial associations between expectancies and e-cigarette use, only one yielded results consistent with hypotheses. Greater e-cigarette use at baseline predicted greater expectancies that e-cigarettes taste pleasant as compared to tobacco cigarettes at 6 months, which then predicted greater e-cigarette use at 12 months. To a lesser degree greater expectancies that e-cigarettes taste pleasant as compared to tobacco cigarettes at baseline predicted greater e-cigarette use at 6 months, which then predicted greater expectancies that e-cigarettes taste pleasant as compared to tobacco cigarettes at 12 months. Expectancies that e-cigarettes provide similar or more pleasant taste sensations as compared to tobacco cigarettes may be both a cause and consequence of e-cigarette use. Focusing on the taste experience may prove most effective in modifying e-cigarette use behavior. The current study offers the first longitudinal examination of expectancies and e

Physics and technology of tunable pulsed single longitudinal mode ...

Indian Academy of Sciences (India)

precious materials. In particular, single-longitudinal mode dye lasers are useful ... to the longitudinal mode spacing of 10 GHz. Grating of 3300 .... the band of wavelength covering 3 pm and SLM operation was shown in the band of 0.5 pm.

Longitudinal changes in white matter microstructure after heavy cannabis use

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Mary P. Becker

2015-12-01

Full Text Available Diffusion tensor imaging (DTI studies of cannabis users report alterations in brain white matter microstructure, primarily based on cross-sectional research, and etiology of the alterations remains unclear. We report findings from longitudinal voxelwise analyses of DTI data collected at baseline and at a 2-year follow-up on 23 young adult (18–20 years old at baseline regular cannabis users and 23 age-, sex-, and IQ-matched non-using controls with limited substance use histories. Onset of cannabis use was prior to age 17. Cannabis users displayed reduced longitudinal growth in fractional anisotropy in the central and parietal regions of the right and left superior longitudinal fasciculus, in white matter adjacent to the left superior frontal gyrus, in the left corticospinal tract, and in the right anterior thalamic radiation lateral to the genu of the corpus callosum, along with less longitudinal reduction of radial diffusion in the right central/posterior superior longitudinal fasciculus, corticospinal tract, and posterior cingulum. Greater amounts of cannabis use were correlated with reduced longitudinal growth in FA as was relatively impaired performance on a measure of verbal learning. These findings suggest that continued heavy cannabis use during adolescence and young adulthood alters ongoing development of white matter microstructure, contributing to functional impairment.

The effect of longitudinal fluctuations in (3+1)D viscous hydrodynamics

Energy Technology Data Exchange (ETDEWEB)

Pang, Long-Gang; Karpenko, Yuri [FIAS, Frankfurt (Germany); Petersen, Hannah [FIAS, Frankfurt (Germany); ITP, Goethe University, Frankfurt (Germany); GSI, Darmstadt (Germany); Huovinen, Pasi [ITP, University of Wroclaw (Poland); Wang, Xin-Nian [CCNU, Wuhan (China); LBNL, Berkeley (United States)

2016-07-01

The energy density fluctuations of the quark gluon plasma (QGP) in the transverse plane are studied in detail and found to be important to explain the high order harmonic flow v{sub n} at RHIC and LHC. However, the energy density fluctuations along longitudinal direction (space-time rapidity η{sub s}) have not been fully investigated yet, even though they should exist as well. Previous studies show that the longitudinal fluctuations strongly depend on the initial entropy deposition mechanisms. In this work AMPT initial conditions are used where HIJING introduces longitudinal fluctuations originating from the asymmetry between forward and backward going participants, string length fluctuations and finite number of partons at different collision energies. The longitudinal fluctuations have been found to be responsible for the de-correlation of anisotropic flow and twist of event planes along rapidity. We study the effect of longitudinal fluctuations on the QGP expansion in both transverse and longitudinal direction within CLVisc, a (3+1)D viscous hydrodynamic code parallelized on GPU using OpenCL, to check whether the anisotropic flow is affected by longitudinal fluctuations and to determine appropriate shear viscosity over entropy density coefficients η/s in comparison with experiments at RHIC and LHC.

Longitudinal and transverse wake potentials in SLAC

International Nuclear Information System (INIS)

Bane, K.; Wilson, P.

1980-01-01

In a machine with short bunches of high peak currents, such as the SLAC collider, one needs to know the longitudinal wake potential, for the higher mode losses, and the transverse wake potential, since, for bunches passing slightly off axis, the induced transverse forces will tend to cause beam break up. The longitudinal and transverse wakes of the SLAC structure presented here, were calculated by computer using the modal method, and including an analytic extension for higher modes. (Auth.)

Worldwide genetic variability of the Duffy binding protein: insights into Plasmodium vivax vaccine development.

Directory of Open Access Journals (Sweden)

Taís Nóbrega de Sousa

Full Text Available The dependence of Plasmodium vivax on invasion mediated by Duffy binding protein (DBP makes this protein a prime candidate for development of a vaccine. However, the development of a DBP-based vaccine might be hampered by the high variability of the protein ligand (DBP(II, known to bias the immune response toward a specific DBP variant. Here, the hypothesis being investigated is that the analysis of the worldwide DBP(II sequences will allow us to determine the minimum number of haplotypes (MNH to be included in a DBP-based vaccine of broad coverage. For that, all DBP(II sequences available were compiled and MNH was based on the most frequent nonsynonymous single nucleotide polymorphisms, the majority mapped on B and T cell epitopes. A preliminary analysis of DBP(II genetic diversity from eight malaria-endemic countries estimated that a number between two to six DBP haplotypes (17 in total would target at least 50% of parasite population circulating in each endemic region. Aiming to avoid region-specific haplotypes, we next analyzed the MNH that broadly cover worldwide parasite population. The results demonstrated that seven haplotypes would be required to cover around 60% of DBP(II sequences available. Trying to validate these selected haplotypes per country, we found that five out of the eight countries will be covered by the MNH (67% of parasite populations, range 48-84%. In addition, to identify related subgroups of DBP(II sequences we used a Bayesian clustering algorithm. The algorithm grouped all DBP(II sequences in six populations that were independent of geographic origin, with ancestral populations present in different proportions in each country. In conclusion, in this first attempt to undertake a global analysis about DBP(II variability, the results suggest that the development of DBP-based vaccine should consider multi-haplotype strategies; otherwise a putative P. vivax vaccine may not target some parasite populations.

Horizontal-Longitudinal Correlations of Acoustic Field in Deep Water

International Nuclear Information System (INIS)

Li Jun; Li Zheng-Lin; Ren Yun; Li Wen; Zhang Ren-He

2015-01-01

The horizontal-longitudinal correlations of the acoustic field in deep water are investigated based on the experimental data obtained in the South China Sea. It is shown that the horizontal-longitudinal correlation coefficients in the convergence zone are high, and the correlation length is consistent with the convergence zone width, which depends on the receiver depth and range. The horizontal-longitudinal correlation coefficients in the convergence zone also have a division structure for the deeper receiver. The signals from the second part of the convergence zone are still correlated with the reference signal in the first part. The horizontal-longitudinal correlation coefficients in the shadow zone are lower than that in the convergence zone, and the correlation length in the shadow zone is also much shorter than that in the convergence zone. The numerical simulation results by using the normal modes theory are qualitatively consistent with the experimental results. (paper)

A New Kicker for the TLS Longitudinal Feedback System

CERN Document Server

Lau, Wai-Keung; Dehler, Micha; Hsu, Kuo-Tung; Hsu, San-Yuang; Jung Chou Ping; Wei Chen, Cheng; Yang Chen Huan; Yang Tze Te

2005-01-01

A new longitudinal kicker that is modified from the Swiss Light Source (SLS) design to fit into the TLS storage ring. It will be served as the actuator in the longitudinal multi-bunch feedback control loop. Beam coupling impedance has been calculated by Gdfidl with a PC cluster. Previous to the installation of this new kicker, bench measurement has been performed in the laboratory to characterize this new kicker. The experimental setups for bandwidth and coaxial wire measurement of longitudinal coupling impedance and their corresponding test results will be reported. As a cross check, bead-pull measurement has also been done to verify the beam coupling measurement by coaxial wire method at the kicker center frequency. Longitudinal field profile of the accelerating mode along the beam path has also been mapped. High order cavity modes of the kicker have also been observed and their effects on the beam are evaluated.

Molecular detection of Anaplasma phagocytophilum DNA in the lesser horseshoe bat (Rhinolophus hipposideros) guano.

Science.gov (United States)

Afonso, E; Goydadin, A-C

2018-05-30

Although bats are increasingly recognised as potential reservoir hosts of human zoonotic pathogens, bacteria in bats are still poorly studied. To investigate the DNA faecal prevalence of the bacterium Anaplasma phagocytophilum, we sampled 23 lesser horseshoe bat (Rhinolophus hipposideros) maternity colonies located in buildings (churches, barns) in rural villages of eastern France. A total of 552 faecal samples were collected from 278 individuals. Anaplasma phagocytophilum DNA was detected in the faeces of 63 individuals (22.7%). Such high prevalence might suggest persistent infection in bats and/or a frequent consumption of insect preys carrying bacteria. Faecal DNA prevalence varied highly among colonies but was not related to the colony size. Faecal DNA prevalence was the highest in the Jura Department, where the density of ticks is known to be the highest across the study area. Because the sampled bats live in close proximity to humans, we discuss how concerning the presence of A. phagocytophilum DNA in bat guano is for humans frequenting places of worship that shelter bats. We also advocate future research to understand what a high faecal DNA prevalence in bat guano really implicates in terms of bacteria transmission.

Vitamin D binding protein: a multifunctional protein of clinical importance.

Science.gov (United States)

Speeckaert, Marijn M; Speeckaert, Reinhart; van Geel, Nanja; Delanghe, Joris R

2014-01-01

Since the discovery of group-specific component and its polymorphism by Hirschfeld in 1959, research has put spotlight on this multifunctional transport protein (vitamin D binding protein, DBP). Besides the transport of vitamin D metabolites, DBP is a plasma glycoprotein with many important functions, including sequestration of actin, modulation of immune and inflammatory responses, binding of fatty acids, and control of bone development. A considerable DBP polymorphism has been described with a specific allele distribution in different geographic area. Multiple studies have shed light on the interesting relationship between polymorphisms of the DBP gene and the susceptibility to diseases. In this review, we give an overview of the multifunctional character of DBP and describe the clinical importance of DBP and its polymorphisms. Finally, we discuss the possibilities to use DBP as a novel therapeutic agent.

Longitudinal muscle of the esophagus: its role in esophageal health and disease.

Science.gov (United States)

Mittal, Ravinder K

2013-07-01

The muscularis propria of the esophagus is organized into circular and longitudinal muscle layers. The function of the longitudinal muscle and its role in bolus propulsion are not clear. The goal of this review is to summarize what is known of the role of the longitudinal muscle in health, as well as in sensory and motor disorders of the esophagus. Simultaneous manometry and ultrasound imaging reveal that, during peristalsis, the two muscle layers of the esophagus contract in perfect synchrony. On the contrary, during transient lower esophageal sphincter (LES) relaxation, longitudinal muscle contracts independent of the circular muscle. Recent studies have provided novel insights into the role of the longitudinal muscle in LES relaxation and descending relaxation of the esophagus. In certain diseases (e.g. some motility disorders of the esophagus), there is discoordination between the two muscle layers, which likely plays an important role in the genesis of dysphagia and delayed esophageal emptying. There is close temporal correlation between prolonged contractions of the longitudinal muscles of the esophagus and esophageal 'angina-like' pain. Novel techniques to record longitudinal muscle contraction are reviewed. Longitudinal muscles of the esophagus play a key role in the physiology and pathophysiology of esophageal sensory and motor function. Neuro-pharmacologic controls of circular and longitudinal muscle are different, which provides an opportunity for the development of novel pharmacological therapies in the treatment of esophageal sensory and motor disorders.

The re-identification risk of Canadians from longitudinal demographics

Science.gov (United States)

2011-01-01

Background The public is less willing to allow their personal health information to be disclosed for research purposes if they do not trust researchers and how researchers manage their data. However, the public is more comfortable with their data being used for research if the risk of re-identification is low. There are few studies on the risk of re-identification of Canadians from their basic demographics, and no studies on their risk from their longitudinal data. Our objective was to estimate the risk of re-identification from the basic cross-sectional and longitudinal demographics of Canadians. Methods Uniqueness is a common measure of re-identification risk. Demographic data on a 25% random sample of the population of Montreal were analyzed to estimate population uniqueness on postal code, date of birth, and gender as well as their generalizations, for periods ranging from 1 year to 11 years. Results Almost 98% of the population was unique on full postal code, date of birth and gender: these three variables are effectively a unique identifier for Montrealers. Uniqueness increased for longitudinal data. Considerable generalization was required to reach acceptably low uniqueness levels, especially for longitudinal data. Detailed guidelines and disclosure policies on how to ensure that the re-identification risk is low are provided. Conclusions A large percentage of Montreal residents are unique on basic demographics. For non-longitudinal data sets, the three character postal code, gender, and month/year of birth represent sufficiently low re-identification risk. Data custodians need to generalize their demographic information further for longitudinal data sets. PMID:21696636

Dissolution properties of cerium dibutylphosphate corrosion inhibitors

NARCIS (Netherlands)

Soestbergen, van M.; Erich, S.J.F.; Huinink, H.P.; Adan, O.C.G.

2013-01-01

The corrosion inhibitor cerium dibutylphosphate, Ce(dbp)3, prevents corrosion by cerium and dbp deposition at the alkaline cathode and acidic anode respectively. The pH dependent Ce(dbp)3 solubility seems to play an essential role in the inhibition degree. We found that Ce(dbp)3 scarcely dissolves

Development of longitudinally excited CO2 laser

Science.gov (United States)

Masroon, N. S.; Tanaka, M.; Tei, M.; Uno, K.; Tsuyama, M.; Nakano, H.

2018-05-01

Simple, compact, and affordable discharged-pumped CO2 laser controlled by a fast high voltage solid state switch has been developed. In this study, longitudinal excitation scheme has been adapted for simple configuration. In the longitudinal excitation scheme, the discharge is produced along the direction of the laser axis, and the electrodes are well separated with a small discharge cross-section. Triggered spark gap switch is usually used to switch out the high voltage because of simple and low cost. However, the triggered spark gap operates in the arc mode and suffer from recovery problem causing a short life time and low efficiency for high repetition rate operation. As a result, there is now considerable interest in replacing triggered spark gap switch with solid state switches. Solid state switches have significant advantages compared to triggered spark gap switch which include longer service lifetime, low cost and stable high trigger pulse. We have developed simple and low cost fast high voltage solid state switch that consists of series connected-MOSFETs. It has been installed to the longitudinally excited CO2 laser to realize the gap switch less operation. Characteristics of laser oscillation by varying the discharge length, charging voltage, capacitance and gas pressure have been evaluated. Longer discharge length produce high power of laser oscillation. Optimum charging voltage and gas pressure were existed for longitudinally excited CO2 laser.

A Longitudinal Study of Adolescent Adjustment Following Family Transitions

Science.gov (United States)

Ruschena, Eda; Prior, Margot; Sanson, Ann; Smart, Diana

2005-01-01

Background: This study examined the impact of family transitions, that is, parental separation, divorce, remarriage and death, upon the lives of Australian children and adolescents in a longitudinal study of temperament and development. Methods: Using longitudinal and concurrent questionnaire data, outcomes for young people experiencing…

Longitudinal coupled-bunch instability studies in the PS

CERN Document Server

Damerau, H

2017-01-01

The main longitudinal limitation for LHC-type beams inthe PS are coupled-bunch instabilities. A dedicated proto-typefeedbacksystemusingaFinemetcavityasalongitudinalkicker has been installed. Extensive tests with beam havebeen performed to explore the intensity reach with this feed-back. The maximum intensity with nominal longitudinalemittance at PS extraction has been measured, as well as theemittance required to keep the beam longitudinally stableat the design intensity for the High-Luminosity LHC (HL-LHC). A higher-harmonic cavity is a complementary op-tion to extend the intensity reach beyond the capabilities ofthe coupled-bunch feedback. Preliminary machine develop-ment (MD) studies operating one20MHzor one40MHzRF system as a higher harmonic at the flat-top indicate thebeneficial effect on longitudinal beam stability

Using administrative data for longitudinal substance abuse research.

Science.gov (United States)

Evans, Elizabeth; Grella, Christine E; Murphy, Debra A; Hser, Yih-Ing

2010-04-01

The utilization of administrative data in substance abuse research has become more widespread than ever. This selective review synthesizes recent extant research from 31 articles to consider what has been learned from using administrative data to conduct longitudinal substance abuse research in four overlapping areas: (1) service access and utilization, (2) underrepresented populations, (3) treatment outcomes, and (4) cost analysis. Despite several notable limitations, administrative data contribute valuable information, particularly in the investigation of service system interactions and outcomes among substance abusers as they unfold and influence each other over the long term. This critical assessment of the advantages and disadvantages of using existing administrative data within a longitudinal framework should stimulate innovative thinking regarding future applications of administrative data for longitudinal substance abuse research purposes.

Simulation of the ALS longitudinal multibunch feedback system

International Nuclear Information System (INIS)

Byrd, J.

1993-05-01

Longitudinal coupled bunch growth rates in the Advanced Light Source (ALS), a 1.5 GeV electron storage ring for producing synchrotron radiation, indicate the need for damping via a feedback (FB) system. The design of the system is based on the proposed PEP-II longitudinal FB system which uses a digital filter to provide the required phase and amplitude response. We report the results of a detailed computer simulation of the FB system including single particle longitudinal beam dynamics, measured RF cavity fundamental and higher order modes, and response of major FB components such as the power amplifier and kicker. The simulation addresses issues such as required FB power and gain, noise, digital filter effects, and varying initial bunch conditions

Vitamin D-Binding Protein Levels in Plasma and Gingival Crevicular Fluid of Patients with Generalized Aggressive Periodontitis

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Xin Zhang

2014-01-01

Full Text Available Vitamin D-binding protein (DBP is the main transport protein of vitamin D and plays an important role in the immune system and host defenses. The purpose of this study was to measure DBP levels in plasma and gingival crevicular fluid (GCF of patients with generalized aggressive periodontitis (GAgP, in comparison to healthy controls, with the goal of elucidating the relationship between DBP and GAgP. Fifty-nine GAgP patients and 58 healthy controls were recruited for the study; clinical parameters of probing depths (PD, bleeding index, and attachment loss (AL were recorded. DBP levels were measured by enzyme-linked immunosorbent assay. From the results, GAgP patients had higher plasma DBP concentrations (P<0.001 but lower GCF DBP concentrations (P<0.001 than healthy controls. In GAgP group, after controlling the potential confounders of age, gender, smoking status, and BMI index, GCF DBP concentrations correlated negatively with PD (P<0.001 and AL (P=0.009. Within the limits of the study, we concluded that decreased GCF DBP level and increased plasma DBP level are associated with periodontitis.

Comparing Longitudinal Profile Patterns of Mathematics and Reading in Early Child Longitudinal Study, Kindergarten: The Profile Analysis via Multidimensional Scaling (PAMS) Approach

Science.gov (United States)

Kim, Se-Kang

2010-01-01

The aim of the study is to compare longitudinal patterns from Mathematics and Reading data from the direct child assessment of Early Child Longitudinal Study, Kindergarten (ECLS-K, US Department of Education, National Center for Education Statistics 2006), utilizing Profile Analysis via Multidimensional Scaling (PAMS). PAMS has been used initially…

Analyzing longitudinal data with the linear mixed models procedure in SPSS.

Science.gov (United States)

West, Brady T

2009-09-01

Many applied researchers analyzing longitudinal data share a common misconception: that specialized statistical software is necessary to fit hierarchical linear models (also known as linear mixed models [LMMs], or multilevel models) to longitudinal data sets. Although several specialized statistical software programs of high quality are available that allow researchers to fit these models to longitudinal data sets (e.g., HLM), rapid advances in general purpose statistical software packages have recently enabled analysts to fit these same models when using preferred packages that also enable other more common analyses. One of these general purpose statistical packages is SPSS, which includes a very flexible and powerful procedure for fitting LMMs to longitudinal data sets with continuous outcomes. This article aims to present readers with a practical discussion of how to analyze longitudinal data using the LMMs procedure in the SPSS statistical software package.

Use of ready-made insoles in the treatment of lesser metatarsalgia: a prospective randomized controlled trial.

Science.gov (United States)

Kelly, A; Winson, I

1998-04-01

Two insoles designed to treat primary lesser metatarsalgia were compared in terms of their effect on plantar pressures and the subjective symptom relief. A prospective single blind randomized trial of 8 weeks' treatment in 46 feet in 33 patients was performed. Subjective outcome measures were visual analogue pain scores and estimated compliance. Objective outcome measures were dynamic plantar pressures using the Musgrave Footprint System. In group 1 (Viscoped), 6 of 18 patients rated themselves much improved or somewhat improved, and in group 2 (Langer) the proportion was 12 of 15 (P = 0.02). Reported mean compliance was 16% higher in the Langer group. Plantar forefoot pressure was lowered by the insoles in all cases. The reduction was significantly greater (P < 0.001) in group 2, both in absolute pressure and as a percentage of initial pressure. Group 2 (Langer) was significantly better in terms of reduction of peak metatarsal pressure. All the subjective outcome measures were better for the group 2 (Langer).

Development of Collagen/Demineralized Bone Powder Scaffolds and Periosteum-Derived Cells for Bone Tissue Engineering Application

Directory of Open Access Journals (Sweden)

Wilairat Leeanansaksiri

2013-01-01

Full Text Available The aim of this study was to investigate physical and biological properties of collagen (COL and demineralized bone powder (DBP scaffolds for bone tissue engineering. DBP was prepared and divided into three groups, based on various particle sizes: 75–125 µm, 125–250 µm, and 250–500 µm. DBP was homogeneously mixed with type I collagen and three-dimensional scaffolds were constructed, applying chemical crosslinking and lyophilization. Upon culture with human periosteum-derived cells (PD cells, osteogenic differentiation of PD cells was investigated using alkaline phosphatase (ALP activity and calcium assay kits. The physical properties of the COL/DBP scaffolds were obviously different from COL scaffolds, irrespective of the size of DBP. In addition, PD cells cultured with COL scaffolds showed significantly higher cell adhesion and proliferation than those with COL/DBP scaffolds. In contrast, COL/DBP scaffolds exhibited greater osteoinductive potential than COL scaffolds. The PD cells with COL/DBP scaffolds possessed higher ALP activity than those with COL scaffolds. PD cells cultured with COL/DBP scaffolds with 250–500 mm particle size yielded the maximum calcium deposition. In conclusion, PD cells cultured on the scaffolds could exhibit osteoinductive potential. The composite scaffold of COL/DBP with 250–500 mm particle size could be considered a potential bone tissue engineering implant.

Operation of PEP longitudinal feedback system

International Nuclear Information System (INIS)

Allen, M.A.; Karvonen, L.G.; McConnell, R.A.; Schwarz, H.

1981-03-01

In order to suppress longitudinal coupled-bunch oscillations which might limit the capabilities of PEP, the 18 GeV e + e - storage ring at SLAC, a longitudinal feedback system is utilized. A frequency domain feedback system was chosen with the frequency spectrum of the stored beam being sampled close to a symmetry point in the ring where the feedback cavity itself is also located. The symmetry point chosen is symmetry point 5 which lies half-way between interaction regions 4 and 6. The system has been installed in PEP and is now operational. However, at stored currents up to the maximum stored in PEP to date at 14.5 GeV (approximately 40 mA in 6 bunches), the ring has been stable to all modes of longitudinal coupled-bunch oscillations both barycentric and the other fundamental modes. By deliberately detuning the main accelerating cavities, small multibunch oscillations can be introduced which, in turn, can be damped by the feedback system. Under optimized beam conditions the feedback system could be adjusted to positive feedback and excite oscillations with relatively small power to the feedback cavity. This will be described along with other details of the system

Longitudinal dynamics and stability in beams for heavy-ion fusion

International Nuclear Information System (INIS)

Sharp, W.M.; Callahan, D.A.; Grote, D.P.

1996-01-01

Successful transport of induction-driven beams for heavy-ion fusion requires careful control of the longitudinal space charge. The usual control technique is the periodic application of time-varying longitudinal electric fields, called 'ears', that on the average, balance the space-charge field. this technique is illustrated using a fluid/envelope code CIRCE, and the sensitivity of the method to errors in these ear fields is illustrated. The possibility that periodic ear fields also excite the longitudinal instability is examined

Age-Related Changes of Intraocular Pressure in Elderly People in Southern China: Lingtou Eye Cohort Study.

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Xiaotong Han

Full Text Available To study age-related changes of intraocular pressure (IOP and assess the cohort effect in both cross-sectional and longitudinal settings among elderly Chinese adults.Participants were enrolled from the Lingtou Eye Cohort Study with Chinese government officials aged 40 years and older at baseline and received physical check-up and ocular examinations from 2010 to 2012. IOP was measured using a non-contact tonometer according to standardized protocols, as well as systolic blood pressure (SBP, diastolic blood pressure (DBP and body mass index (BMI. Participants who had attended IOP measurements in both 2010 and 2012 were included in this study. Cross-sectional association of IOP with age was assessed using multivariate liner regression analyses and based on the data of 2010. Longitudinal changes in IOP were assessed by paired t-test.A total of 3372 subjects were enrolled in the current analysis (2010 mean [SD] age, 61.9 [7.1] years; 60.2% men. The mean IOP in 2010 was 15.4 ± 2.3 mmHg for women and 15.2 ± 2.3 mmHg for men with an intersex difference (P = 0.029. Cross-sectional analysis showed that IOP was negatively associated with age (P = 0.003, β = -0.033 for women and P<0.001, β = -0.061 for men adjusted for baseline SBP, DBP and BMI. Paired t-test suggested that IOP was higher in the year 2012 than 2010 in women (P = 0.006 but did not change significantly in men within 2 years (P = 0.345. In addition, the 2-year changes of IOP were not associated with age adjusted for baseline IOP in 2010 (P = 0.249.Cross-sectional data suggests that IOP is lower in people with older age. Longitudinal data does not support such findings and thus the identified decreasing pattern with age in cross-sectional analysis is likely caused by cohort effects.

Seismic Imaging of the Lesser Antilles Subduction Zone Using S-to-P Receiver Functions: Insights From VoiLA

Science.gov (United States)

Chichester, B.; Rychert, C.; Harmon, N.; Rietbrock, A.; Collier, J.; Henstock, T.; Goes, S. D. B.; Kendall, J. M.; Krueger, F.

2017-12-01

In the Lesser Antilles subduction zone Atlantic oceanic lithosphere, expected to be highly hydrated, is being subducted beneath the Caribbean plate. Water and other volatiles from the down-going plate are released and cause the overlying mantle to melt, feeding volcanoes with magma and hence forming the volcanic island arc. However, the depths and pathways of volatiles and melt within the mantle wedge are not well known. Here, we use S-to-P receiver functions to image seismic velocity contrasts with depth within the subduction zone in order to constrain the release of volatiles and the presence of melt in the mantle wedge, as well as slab structure and arc-lithosphere structure. We use data from 55-80° epicentral distances recorded by 32 recovered broadband ocean-bottom seismometers that were deployed during the 2016-2017 Volatiles in the Lesser Antilles (VoiLA) project for 15 months on the back- and fore-arc. The S-to-P receiver functions are calculated using two methods: extended time multi-taper deconvolution followed by migration to depth to constrain 3-D discontinuity structure of the subduction zone; and simultaneous deconvolution to determine structure beneath single stations. In the south of the island arc, we image a velocity increase with depth associated with the Moho at depths of 32-40 ± 4 km on the fore- and back-arc, consistent with various previous studies. At depths of 65-80 ± 4 km beneath the fore-arc we image a strong velocity decrease with depth that is west-dipping. At 96-120 ± 5 km beneath the fore-arc, we image a velocity increase with depth that is also west-dipping. The dipping negative-positive phase could represent velocity contrasts related to the top of the down-going plate, a feature commonly imaged in subduction zone receiver function studies. The negative phase is strong, so there may also be contributions to the negative velocity discontinuity from slab dehydration and/or mantle wedge serpentinization in the fore-arc.

Measurements of longitudinal phase space in the SLC linac

International Nuclear Information System (INIS)

Bane, K.; Adolphsen, C.; Lavine, T.L.; Ross, M.; Seeman, J.; Thompson, K.

1990-05-01

In the Stanford Linear Collider the beam leaves a damping ring and then enters the Ring-to-Linac (RTL) transfer line. In the RTL it is compressed in length by a factor of 10 by means of an rf section, with which a longitudinally correlated energy variation is induced in the beam, and a following beam line which has non-zero momentum compaction. The compressed beam then enters the linac proper. In this paper we describe three measurements of longitudinal properties of the beam in the SLC linac. We present measurements of single bunch beam loading, of the energy spectrum at the end of the linac, and of the linac bunch length. Since the results of all three measurements depend on the beam's longitudinal charge distribution in the linac they, in turn, also depend on the bunch lengthening that occurs in the damping rings, as well as on the behavior of the compressor. The results of the first two measurements, in addition, depend critically on the strength of the longitudinal wakefields in the linac. The results of these three measurements are compared with simulations. For these calculations, at any given current, the potential well distortion in the damping ring is first computed. The compression process is then simulated to obtain the longitudinal charge distribution in the linac. For the first two measurements this distribution is then convolved with the calculated longitudinal wake function of the SLAC linac in order to obtain the induced voltage. Finally, the induced voltage is combined with the effect of the linac rf wave to give the final energy spectrum. 8 refs., 5 figs

ABRUPT LONGITUDINAL MAGNETIC FIELD CHANGES IN FLARING ACTIVE REGIONS

International Nuclear Information System (INIS)

Petrie, G. J. D.; Sudol, J. J.

2010-01-01

We characterize the changes in the longitudinal photospheric magnetic field during 38 X-class and 39 M-class flares within 65 0 of disk center using 1 minute GONG magnetograms. In all 77 cases, we identify at least one site in the flaring active region where clear, permanent, stepwise field changes occurred. The median duration of the field changes was about 15 minutes and was approximately equal for X-class and for M-class flares. The absolute values of the field changes ranged from the detection limit of ∼10 G to as high as ∼450 G in two exceptional cases. The median value was 69 G. Field changes were significantly stronger for X-class than for M-class flares and for limb flares than for disk-center flares. Longitudinal field changes less than 100 G tended to decrease longitudinal field strengths, both close to disk center and close to the limb, while field changes greater than 100 G showed no such pattern. Likewise, longitudinal flux strengths tended to decrease during flares. Flux changes, particularly net flux changes near disk center, correlated better than local field changes with GOES peak X-ray flux. The strongest longitudinal field and flux changes occurred in flares observed close to the limb. We estimate the change of Lorentz force associated with each flare and find that this is large enough in some cases to power seismic waves. We find that longitudinal field decreases would likely outnumber increases at all parts of the solar disk within 65 0 of disk center, as in our observations, if photospheric field tilts increase during flares as predicted by Hudson et al.

Residents’ perceptions of an integrated longitudinal curriculum: a qualitative study

Directory of Open Access Journals (Sweden)

Rebecca Lubitz

2015-12-01

Conclusions: This study suggests that an integrated longitudinalized family medicine block training model has the potential to support the principles of a longitudinal integrated competency-based curriculum to effectively prepare residents for family medicine practice.

Vitamin D, vitamin D binding protein, lung function and structure in COPD

DEFF Research Database (Denmark)

Berg, Isaac; Hanson, Corrine; Sayles, Harlan

2013-01-01

Vitamin D and vitamin D binding protein (DBP) have been associated with COPD and FEV1. There are limited data regarding emphysema and vitamin D and DBP.......Vitamin D and vitamin D binding protein (DBP) have been associated with COPD and FEV1. There are limited data regarding emphysema and vitamin D and DBP....

Forced copulation results in few extrapair fertilizations in Ross's and lesser snow geese

Science.gov (United States)

Dunn, P.O.; Afton, A.D.; Gloutney, M.L.; Alisauskas, R.T.

1999-01-01

Extrapair paternity varies from 0 to over 70% of young among various populations of birds. Comparative studies have suggested that this variation is related to nesting density, breeding synchrony and the proportion of extrapair copulations. We used minisatellite DNA fingerprinting to examine levels of extrapair paternity in Ross's geese, Chen rossi, and lesser snow geese, C. caerulescens c. (hereafter snow geese) nesting in the largest known goose colony in the world. These geese have one of the highest known percentages of extrapair copulation (46-56% of all attempted copulations), and all of these appeared to be forced. Among all successful copulations, 33 and 38% were extrapair in Ross's and snow geese, respectively. Despite the high percentage of extrapair copulations, extrapair paternity was low in both Ross's and snow geese (2-5% of young). Extrapair paternity was not related to nest density in either species. However, in snow geese, extrapair paternity was more likely to occur in nests of females that nested asynchronously, either early or late in the season. This is one of a few reported examples of a negative relationship between extrapair paternity and breeding synchrony. Extrapair young also tended to come from eggs laid later in the clutch. Although forced extrapair copulations appear to be a relatively inefficient reproductive tactic for males, they may provide a reproductive advantage for some males.

Antisocial Behavior and Depressive Symptoms: Longitudinal and Concurrent Relations

Science.gov (United States)

Vieno, Alessio; Kiesner, Jeff; Pastore, Massimiliano; Santinello, Massimo

2008-01-01

The relations between antisocial behavior and depressive symptoms were examined both longitudinally and concurrently in a sample of Italian early-adolescents. Structural equation modelling was applied to 10-month longitudinal data from a sample of 107 youths (54 girls; mean age at baseline = M = 12.5). Early adolescents completed a questionnaire…

Comparison of torsional and longitudinal modes using phacoemulsification parameters.

Science.gov (United States)

Rekas, Marek; Montés-Micó, Robert; Krix-Jachym, Karolina; Kluś, Adam; Stankiewicz, Andrzej; Ferrer-Blasco, Teresa

2009-10-01

To compare phacoemulsification parameters of torsional and longitudinal ultrasound modes. Ophthalmology Department, Military Health Service Institute, Warsaw, Poland. This prospective study evaluated eyes 1, 7, and 30 days after phacoemulsification with an Infiniti Vision System using the torsional or longitudinal ultrasound (US) mode. Cataract classification was according to the Lens Opacities Classification System II. Nucleus fragmentation was by the phaco-chop and quick-chop methods. Primary outcome measures were phaco time, mean phaco power, mean torsional amplitude, and aspiration time. Total energy, defined as cumulative dissipated energy (CDE) x aspiration time, and the effective coefficient, defined as aspiration time/phaco time, were also calculated. Four hundred eyes were evaluated. The CDE was statistically significantly lower in the torsional mode for nucleus grades I, II, and III (P.05). Aspiration time was statistically significantly shorter in the torsional mode than in the longitudinal mode for nucleus grades III and IV (P<.05). Total energy was significantly lower in the torsional mode for all nucleus densities (P<.05). The effective coefficient was significantly lower in the longitudinal mode except for nucleus grade I (P<.05). Torsional phacoemulsification was more effective than longitudinal phacoemulsification in the amount of applied fluid and the quantity of US energy expended. With the torsional method, it was possible to maintain a constant ratio of amount of fluid flow to quantity of US energy used, regardless of nucleus density.

Longitudinal myelitis associated with yellow fever vaccination.

Science.gov (United States)

Chaves, M; Riccio, P; Patrucco, L; Rojas, J I; Cristiano, E

2009-07-01

Severe adverse reaction to yellow fever (YF) vaccine includes the yellow fever vaccine-associated neurotropic disease. This terminology includes postvaccinal encephalitis, acute disseminated encephalomyelitis, and Guillain-Barré syndrome. The objective of this communication is to report a patient who received a YF vaccine in Argentina and subsequently developed longitudinal myelitis with a symptom that had previously gone unreported in the literature. A 56-year-old man began with progressive paraparesia, urinary retention, and constipation 48 h previous to admission. The patient received YF vaccine 45 days prior to the onset of the symptoms. There was no history of other immunization or relevant condition. MR of the spine showed longitudinal intramedullary hyperintense signal (D5-12) without gadolinium enhancement. A high concentration of YFV-specific IgM vaccine antibody was found in the cerebrospinal fluid (CSF). Serological tests for other flavivirus were negative. A diagnosis of longitudinal myelitis without encephalitis associated with YF vaccine was performed and symptoms improved 5 days later. This is the first report dealing with longitudinal myelitis as a serious adverse event associated with YF vaccination in which confirmation of the presence of antibodies in CSF was found. To date, it is also the first report with serological confirmation in Argentina and in South America. We consider that the present investigation will raise awareness in the region in the reporting of adverse events related to YF vaccine and improve our knowledge of adverse reactions to the vaccine.

Individual or synchronous biodegradation of di-n-butyl phthalate and phenol by Rhodococcus ruber strain DP-2

Energy Technology Data Exchange (ETDEWEB)

He, Zhixing; Niu, Chengzhen; Lu, Zhenmei, E-mail: lzhenmei@zju.edu.cn

2014-05-01

Highlights: • A Rhodococcus ruber strain degraded DBP and phenol. • Degradation kinetics of DBP or phenol fit modified first-order models. • Degradation interaction between DBP and phenol was studied by strain DP-2. • The degradation genes transcriptional were quantified by RT-qPCR. - Abstract: The bacterial strain DP-2, identified as Rhodococcus ruber, is able to effectively degrade di-n-butyl phthalate (DBP) and phenol. Degradation kinetics of DBP and phenol at different initial concentrations revealed DBP and phenol degradation to fit modified first-order models. The half-life of DBP degradation ranged from 15.81 to 27.75 h and phenol degradation from 14.52 to 45.52 h under the initial concentrations of 600–1200 mg/L. When strain DP-2 was cultured with a mixture of DBP (800 mg/L) and phenol (700 mg/L), DBP degradation rate was found to be only slightly influenced; however, phthalic acid (PA) accumulated, and phenol degradation was clearly inhibited during synchronous degradation. Transcriptional levels of degradation genes, phenol hydroxylase (pheu) and phthalate 3,4-dioxygenase (pht), decreased significantly more during synchronous degradation than during individual degradation. Quantitative estimation of individual or synchronous degradation kinetics is essential to manage mixed hazardous compounds through biodegradation in industrial waste disposal.

Comparative study on the degradation of dibutyl phthalate by two newly isolated Pseudomonas sp. V21b and Comamonas sp. 51F

Directory of Open Access Journals (Sweden)

Vinay Kumar

2017-09-01

Full Text Available Dibutyl phthalate is (DBP the top priority toxicant responsible for carcinogenicity, teratogenicity and endocrine disruption. This study demonstrates the DBP degradation capability of the two newly isolated bacteria from municipal solid waste leachate samples. The isolated bacteria were designated as Pseudomonas sp. V21b and Comamonas sp. 51F after scanning electron microscopy, transmission electron microscopy, Gram-staining, antibiotic sensitivity tests, biochemical characterization, 16S-rRNA gene identification and phylogenetic studies. They were able to grow on DBP, benzyl butyl phthalate, monobutyl phthalate, diisodecyl phthalate, dioctyl phthalate, and protocatechuate. It was observed that Pseudomonas sp. V21b was more efficient in DBP degradation when compared with Comamonas sp. 51F. It degraded 57% and 76% of the initial DBP in minimal salt medium and in DBP contaminated samples respectively. Kinetics for the effects of DBP concentration on Pseudomonas sp. V21b and Comamonas sp. 51F growth was also evaluated. Stoichiometry for DBP degradation and biomass formation were compared for both the isolates. Two major metabolites diethyl phthalate and monobutyl phthalates were identified using GC–MS in the extracts. Key genes were amplified from the genomes of Pseudomonas sp. V21b and Comamonas sp. 51F. DBP degradation pathway was also proposed.

Longitudinal and transverse polarizations in the deep inelastic reactions

International Nuclear Information System (INIS)

Bressan, A.

1996-07-01

This course is an introduction to the dominant effects of longitudinal and transverse spin in deep inelastic reactions. Only the effects present to the 'leading twist' are attacked. The mass and transverse impulsion of partons are neglected. We will attach to bring out the respective specificities of longitudinal and transverse polarizations. (N.C.)

Single bunch fast longitudinal instability

International Nuclear Information System (INIS)

Wang, J.M.; Pellegrini, C.

1979-01-01

Single bunch longitudinal instability producing an increase of the bunch areas has been observed in proton synchrotron and storage rings. Singals at microwave frequencies are observed during the bunch blow-up and because of this the effect has been called the microwave instability. A similar increase in bunch area is observed also in electron storage rings, where it is usually referred to as the bunch lengthening effect. This paper is an attempt to obtain a more general theory of this effect. Here we describe the model used and the method of calculation, together with some general results. The main result of this paper is the derivation of a condition for the existence of a fast longitudinal bunch blow-up. This condition is a generalized threshold formula, showing explicitly the dependence on the bunch energy spread and length

Simulations of longitudinally pumped dye laser amplifier

International Nuclear Information System (INIS)

Takehisa, Kiwamu; Takemori, Satoshi

1995-01-01

Simulations of a copper laser pumped dye laser amplifier and new designs of the longitudinally pumped dye laser amplifier are presented. The simulations take the consideration of the amplified spontaneous emission (ASE). The new designs utilize a center-hole reflector instead of a dichroic mirror. The simulation results indicate that the poor spatial overlap between the pump beam and the dye beam in the transverse pumping not only reduces the laser output power, but also generates ASE strongly. The results also indicate that the longitudinal pumping is as efficient as the transverse pumping. (author)

Longitudinal tibial epiphyseal bracket in Nievergelt syndrome

International Nuclear Information System (INIS)

Burnstein, M.I.; De Smet, A.A.; Breed, A.L.; Thomas, J.R.; Hafez, G.R.

1989-01-01

A patient is described with lower extremity mesomelic dwarfism associated with bilateral congenital elbow, hip, and knee dislocations. Rhomboid-shaped tibiae and delayed ossification of the primary fibular ossification centers were demonstrated at birth. Plain films and magnetic resonance imaging revealed that the tibial deformities were due to the presence of longitudinal epiphyseal brackets. These brackets were observed at surgery and confirmed histologically. Recognition of the longitudinal epiphyseal bracket and its relationship to the tibial deformities seen in this patient with Nievergelt syndrome is important for planning surgical treatment. (orig.)

Longitudinal tibial epiphyseal bracket in Nievergelt syndrome

Energy Technology Data Exchange (ETDEWEB)

Burnstein, M.I.; De Smet, A.A.; Breed, A.L.; Thomas, J.R.; Hafez, G.R.

1989-04-01

A patient is described with lower extremity mesomelic dwarfism associated with bilateral congenital elbow, hip, and knee dislocations. Rhomboid-shaped tibiae and delayed ossification of the primary fibular ossification centers were demonstrated at birth. Plain films and magnetic resonance imaging revealed that the tibial deformities were due to the presence of longitudinal epiphyseal brackets. These brackets were observed at surgery and confirmed histologically. Recognition of the longitudinal epiphyseal bracket and its relationship to the tibial deformities seen in this patient with Nievergelt syndrome is important for planning surgical treatment. (orig.).

GIS habitat analysis for lesser prairie-chickens in southeastern New Mexico

Directory of Open Access Journals (Sweden)

Neville Paul

2006-12-01

Full Text Available Abstract Background We conducted Geographic Information System (GIS habitat analyses for lesser prairie-chicken (LPCH, Tympanuchus pallidicinctus conservation planning. The 876,799 ha study area included most of the occupied habitat for the LPCH in New Mexico. The objectives were to identify and quantify: 1. suitable LPCH habitat in New Mexico, 2. conversion of native habitats, 3. potential for habitat restoration, and 4. unsuitable habitat available for oil and gas activities. Results We found 16% of suitable habitat (6% of the study area distributed in 13 patches of at least 3,200 ha and 11% of suitable habitat (4% of the study area distributed in four patches over 7,238 ha. The area converted from native vegetation types comprised 17% of the study area. Ninety-five percent of agricultural conversion occurred on private lands in the northeastern corner of the study area. Most known herbicide-related conversions (82% occurred in rangelands in the western part of the study area, on lands managed primarily by the US Bureau of Land Management (BLM. We identified 88,190 ha (10% of the study area of habitats with reasonable restoration potential. Sixty-two percent of the primary population area (PPA contained occupied, suitable, or potentially suitable habitat, leaving 38% that could be considered for oil and gas development. Conclusion Although suitable LPCH habitat appears at first glance to be abundant in southeastern New Mexico, only a fraction of apparently suitable vegetation types constitute quality habitat. However, we identified habitat patches that could be restored through mesquite control or shin-oak reintroduction. The analysis also identified areas of unsuitable habitat with low restoration potential that could be targeted for oil and gas exploration, in lieu of occupied, high-quality habitats. Used in combination with GIS analysis and current LPCH population data, the habitat map represents a powerful conservation and management tool.

GIS habitat analysis for lesser prairie-chickens in southeastern New Mexico.

Science.gov (United States)

Johnson, Kristine; Neville, Teri B; Neville, Paul

2006-12-04

We conducted Geographic Information System (GIS) habitat analyses for lesser prairie-chicken (LPCH, Tympanuchus pallidicinctus) conservation planning. The 876,799 ha study area included most of the occupied habitat for the LPCH in New Mexico. The objectives were to identify and quantify: 1. suitable LPCH habitat in New Mexico, 2. conversion of native habitats, 3. potential for habitat restoration, and 4. unsuitable habitat available for oil and gas activities. We found 16% of suitable habitat (6% of the study area) distributed in 13 patches of at least 3,200 ha and 11% of suitable habitat (4% of the study area) distributed in four patches over 7,238 ha. The area converted from native vegetation types comprised 17% of the study area. Ninety-five percent of agricultural conversion occurred on private lands in the northeastern corner of the study area. Most known herbicide-related conversions (82%) occurred in rangelands in the western part of the study area, on lands managed primarily by the US Bureau of Land Management (BLM). We identified 88,190 ha (10% of the study area) of habitats with reasonable restoration potential. Sixty-two percent of the primary population area (PPA) contained occupied, suitable, or potentially suitable habitat, leaving 38% that could be considered for oil and gas development. Although suitable LPCH habitat appears at first glance to be abundant in southeastern New Mexico, only a fraction of apparently suitable vegetation types constitute quality habitat. However, we identified habitat patches that could be restored through mesquite control or shin-oak reintroduction. The analysis also identified areas of unsuitable habitat with low restoration potential that could be targeted for oil and gas exploration, in lieu of occupied, high-quality habitats. Used in combination with GIS analysis and current LPCH population data, the habitat map represents a powerful conservation and management tool.

A ¤nonparametric dynamic additive regression model for longitudinal data

DEFF Research Database (Denmark)

Martinussen, T.; Scheike, T. H.

2000-01-01

dynamic linear models, estimating equations, least squares, longitudinal data, nonparametric methods, partly conditional mean models, time-varying-coefficient models......dynamic linear models, estimating equations, least squares, longitudinal data, nonparametric methods, partly conditional mean models, time-varying-coefficient models...

Preparation of industrial chemicals by acid leaching from the koga nepheline syenite, southern Swat, lesser Himalayas-Pakistan

International Nuclear Information System (INIS)

Nizami, A.R.

2012-01-01

This paper encompasses the study on the preparation of industrial chemicals by acid leaching from the Koga nepheline syenite, Southern Swat, Lesser Himalayas-Pakistan. These rocks have been studied in detail by many workers to exploit their industrial utility in the form of powdered rock material in glass and ceramics and steel industry. The present authors for the first time carried out acid leaching studies and prepared a number of industrial chemicals, like, alumina, aluminium sulphate, sodium and ammonium alums, sodium sulphate) and sodium bisulphate by simple chemical reactions at bench scale successfully. The developed process is simple and economically viable. It is recommended to exploit this process in cottage industry in the mountainous areas hosting these rocks for the benefit of local population. The research and development work for production of these chemicals at pilot plant and industrial scale is recommended as well. (author)

Formation of longitudinal axon pathways in Caenorhabditis elegans.

Science.gov (United States)

Hutter, Harald

2017-11-18

The small number of neurons and the simple architecture of the Caenorhabditis elegans (C. elegans) nervous system enables researchers to study axonal pathfinding at the level of individually identified axons. Axons in C. elegans extend predominantly along one of the two major body axes, the anterior-posterior axis and the dorso-ventral axis. This review will focus on axon navigation along the anterior-posterior axis, leading to the establishment of the longitudinal axon tracts, with a focus on the largest longitudinal axon tract, the ventral nerve cord (VNC). In the VNC, axons grow out in a stereotypic order, with early outgrowing axons (pioneers) playing an important role in guiding later outgrowing (follower) axons. Genetic screens have identified a number of genes specifically affecting the formation of longitudinal axon tracts. These genes include secreted proteins, putative receptors and adhesion molecules, as well as intracellular proteins regulating the cell's response to guidance cues. In contrast to dorso-ventral navigation, no major general guidance cues required for the establishment of longitudinal pathways have been identified so far. The limited penetrance of defects found in many mutants affecting longitudinal navigation suggests that guidance cues act redundantly in this process. The majority of the axon guidance genes identified in C. elegans are evolutionary conserved, i.e. have homologs in other animals, including vertebrates. For a number of these genes, a role in axon guidance has not been described outside C. elegans. Taken together, studies in C. elegans contribute to a fundamental understanding of the molecular basis of axonal navigation that can be extended to other animals, including vertebrates and probably humans as well. Copyright © 2017. Published by Elsevier Ltd.

Suppression of Longitudinal Coupled-Bunch Instabilities at the KEK-PF

International Nuclear Information System (INIS)

Obina, T.; Tobiyama, M.; Honda, T.; Tadano, M.; Flanagan, J.W.; Mitsuhashi, T.; Cheng, W.X.; Fox, J.D.; Teytelman, D.

2012-01-01

A bunch-by-bunch feedback system has been developed to suppress longitudinal coupled-bunch instabilities at the KEK-PF. A longitudinal kicker based on a DAFNE-type overdamped cavity has been designed and installed in the ring, and a general purpose signal processor, called iGp, has been developed by the collaboration of the KEK, SLAC, and INFN-LNF. The entire feedback loop has been closed by the end of June 2007, and the feedback system has successfully suppressed the longitudinal dipole-mode instabilities up to 430 mA.

Current Population Status and Activity Pattern of Lesser Flamingos (Phoeniconaias minor and Greater Flamingo (Phoenicopterus roseus in Abijata-Shalla Lakes National Park (ASLNP, Ethiopia

Directory of Open Access Journals (Sweden)

Tewodros Kumssa

2014-01-01

Full Text Available A study of the population status, habitat preference, and activity pattern of nonbreeding flamingos was carried out in Lakes Abijata, Shalla, and Chitu, part of the Great Rift Valley, Ethiopia, from 2011 to 2013. The current population status and habitat preference of flamingos in the area are still poorly known. Likewise, data on diurnal and seasonal activity pattern of the species are scarce and this leads to the misunderstanding of how Flamingos use local wetlands throughout the different seasons. Data regarding population size and activity pattern were gathered during the wet and dry seasons. Point-count method was used to estimate the population size. Behaviors were recorded using scan sampling techniques. A total of 53671 individuals representing two species of flamingo were counted during both wet and dry seasons from the three lakes. There were more flamingos during the dry season than the wet season in Lake Abijata contrary to Lakes Shalla and Chitu during the wet season. Lesser flamingos (Phoeniconaias minor were the most abundant species comprising 95.39%, while Greater Flamingos (Phoenicopterus roseus accounted for 4.61% of the total population. Lake Abijata is the major stronghold of Lesser Flamingos in the area. There was significant variation in the mean number of both species during the wet and dry season in the different study sites of the lake, respectively. The species were known to use varied habitats within the lakes. The Lesser Flamingo mainly preferred the shoreline and mudflat areas of the lakes. However, Greater Flamingo on several occasions showed preference to offshore area of the lakes. Seasonal average flock sizes were not similar between the species. There was a strong relationship between time allocated to each activity and time of day. Feeding activity varied among daylight hours and was higher in the evening (76.5% and late morning (74.56% and least during midday (54%. Some variations in activity breakdown were

Longitudinal halo in beam bunches with self-consistent 6-D distributions

International Nuclear Information System (INIS)

Gluckstern, R. L.; Fedotov, A. V.; Kurennoy, S. S.; Ryne, R. D.

1998-01-01

We have explored the formation of longitudinal and transverse halos in 3-D axisymmetric beam bunches by starting with a self-consistent 6-D phase space distribution. Stationary distributions allow us to study the halo development mechanism without being obscured by beam redistribution and its effect on halo formation. The beam is then mismatched longitudinally and/or transversely, and we explore the rate, intensity and spatial extent of the halos which form, as a function of the beam charge and the mismatches. We find that the longitudinal halo forms first because the longitudinal tune depression is more severe than the transverse one for elongated bunches and conclude that it plays a major role in halo formation

Detection of vitamin D binding protein on the surface of cytotrophoblasts isolated from human placentae

International Nuclear Information System (INIS)

Nestler, J.E.; McLeod, J.F.; Kowalski, M.A.; Strauss, J.F. III; Haddad, J.G. Jr.

1987-01-01

Vitamin D binding protein (DBP), a Mr 56,000-58,000 alpha 2-glycoprotein, is the major serum protein involved in the transport of vitamin D sterols. Recently it has been suggested that DBP may also be involved in immunoglobulin G binding to cells. Because the trophoblast is involved in the transport of molecules such as vitamin D and immunoglobulin G to the fetus, we asked whether DBP could be detected on the surface of human placental trophoblast cells. Cytotrophoblasts purified from human term placentae were fixed and made permeant with Triton X-100 and examined by indirect immunofluorescence after incubation with a monoclonal antibody to DBP. Greater than 90% of these cells stained positively, whereas no staining was observed with nonimmune antiserum. The presence of DBP on/in the surface of cytotrophoblasts could also be demonstrated by fluorescent cytometry. When cell surface-associated proteins of cytotrophoblasts were radioiodinated, a Mr 57,000 radiolabeled protein could be immunoisolated from the cell lysate with a purified monospecific polyclonal antibody to DBP. Immunoisolation of this radiolabeled protein was prevented by the addition of excess unlabeled human DBP to the cell lysate before incubation with antibody. This Mr 57,000 radiolabeled protein could also be isolated by affinity chromatography selecting for proteins that bind to globular actin. When cytotrophoblasts were incubated with [ 35 S]methionine for 3 or 18 h, active synthesis of DBP could not be demonstrated by immunoisolation techniques. These studies demonstrate the presence of DBP on the surface of well washed, human cytotrophoblasts. This DBP may be maternally derived, since active synthesis of DBP could not be demonstrated

Time-dependent efficacy of longitudinal biomarker for clinical endpoint.

Science.gov (United States)

Kolamunnage-Dona, Ruwanthi; Williamson, Paula R

2018-06-01

Joint modelling of longitudinal biomarker and event-time processes has gained its popularity in recent years as they yield more accurate and precise estimates. Considering this modelling framework, a new methodology for evaluating the time-dependent efficacy of a longitudinal biomarker for clinical endpoint is proposed in this article. In particular, the proposed model assesses how well longitudinally repeated measurements of a biomarker over various time periods (0,t) distinguish between individuals who developed the disease by time t and individuals who remain disease-free beyond time t. The receiver operating characteristic curve is used to provide the corresponding efficacy summaries at various t based on the association between longitudinal biomarker trajectory and risk of clinical endpoint prior to each time point. The model also allows detecting the time period over which a biomarker should be monitored for its best discriminatory value. The proposed approach is evaluated through simulation and illustrated on the motivating dataset from a prospective observational study of biomarkers to diagnose the onset of sepsis.

Combined lateral and longitudinal CACC for a unicycle-type platoon

NARCIS (Netherlands)

Bayuwindra, A.; Aakre, O.L.; Ploeg, J.; Nijmeijer, H.

2016-01-01

This paper presents the controller design for combined lateral and longitudinal Cooperative Adaptive Cruise Control (CACC) for a unicycle-type platoon with emphasis on the cornering maneuvers. A decentralized controller for lateral and longitudinal behavior is designed using input-output

Fingerprints of transversal and longitudinal coupling between induced open quantum dots in the longitudinal magneto-conductance through anti-dot lattices

International Nuclear Information System (INIS)

Ujevic, Sebastian; Mendoza, Michel

2011-01-01

Full text. We propose numerical simulations of longitudinal magneto conductance through a finite anti dot lattice located inside an open quantum dot with a magnetic field applied perpendicular to the plane. The system is connected to reservoirs using quantum point contacts. We discuss the relationship between the longitudinal magneto conductance and the generation of transversal couplings between the induced open quantum dots in the system. The system presents longitudinal magneto conductance maps with crossovers (between transversal bands) and closings (longitudinal decoupling) of fundamental quantum states related to the open quantum dots induced by the anti dot lattice. A relationship is observed between the distribution of anti dots and the formed conductance bands, allowing a systematic follow-up of the bands as a function of the applied magnetic field and quantum point contact width. We observed a high conductance intensity (between n- and (n + 1)-quantum of conductance, n = 1; 2...) in the regions of crossover and closing of states. This suggests transversal couplings between the induced open quantum dots of the system that can be modulated by varying both the anti dots potential and the quantum point contact width. A new continuous channel (not expected) is induced by the variation of the contact width and generate Fano resonances in the conductance. These resonances can be manipulated by the applied magnetic field

Longitudinal and postural changes of blood pressure predict dementia: the Malmö Preventive Project.

Science.gov (United States)

Holm, Hannes; Nägga, Katarina; Nilsson, Erik D; Melander, Olle; Minthon, Lennart; Bachus, Erasmus; Fedorowski, Artur; Magnusson, Martin

2017-04-01

The role of blood pressure (BP) changes in dementia is debatable. We aimed to analyse how resting and postural BP changes relate to incident dementia over a long-term follow-up. In the prospective population-based Malmö Preventive Project, 18,240 study participants (mean age: 45 ± 7 years, 63% male) were examined between 1974 and 1992 with resting and standing BP measurement, and re-examined between 2002 and 2006 at mean age of 68 ± 6 years with resting BP. A total of 428 participants (2.3%) were diagnosed with dementia through Dec 31, 2009. The association of resting and postural BP changes with risk of dementia was studied using multivariable-adjusted Cox regression models controlling for traditional risk factors. Diastolic BP (DBP) decrease on standing indicated higher risk of dementia [Hazard ratio (HR) per 10 mmHg: 1.22; 95% confidence interval (CI) 1.01-1.44, p = 0.036], which was mainly driven by increased risk in normotensive individuals. Higher systolic (SBP) and diastolic BP at re-examination was associated with lower risk of dementia (HR per 10 mmHg: 0.94; 95% CI 0.89-0.99, p = 0.011; and 0.87; 0.78-0.96, p = 0.006, respectively). Extreme decrease in SBP/DBP between baseline and re-examination (4th quartile; -7 ± 12/-15 ± 7 mmHg, respectively) indicated higher risk of dementia (HR 1.46; 95% CI 1.11-1.93, p = 0.008, and 1.54; 95% CI 1.14-2.08, p = 0.005; respectively) compared with reference group characterised by pronounced BP increase over the same period (1st quartile; +44 ± 13/+15 ± 7 mmHg). Diastolic BP decrease on standing in the middle age, decline in BP between middle-and advanced age, and lower BP in advanced age are independent risk factors of developing dementia.

Nucleon Spin Structure: Longitudinal and Transverse

International Nuclear Information System (INIS)

Chen, Jian-Ping

2011-01-01

Inclusive Deep-Inelastic Scattering (DIS) experiments have provided us with the most extensive information on the unpolarized and longitudinal polarized parton (quark and gluon) distributions in the nucleon. It has becoming clear that transverse spin and transverse momentum dependent distributions (TMDs) study are crucial for a more complete understanding of the nucleon structure and the dynamics of the strong interaction. The transverse spin structure and the TMDs are the subject of increasingly intense theoretical and experimental study recently. With a high luminosity electron beam facility, JLab has played a major role in the worldwide effort to study both the longitudinal and transverse spin structure. Highlights of recent results will be presented. With 12-GeV energy upgrade, JLab will provide the most precise measurements in the valence quark region to close a chapter in longitudinal spin study. JLab will also perform a multi-dimensional mapping of the transverse spin structure and TMDs in the valence quark region through Semi-Inclusive DIS (SIDIS) experiments, providing a 3-d partonic picture of the nucleon in momentum space and extracting the u and d quark tensor charges of the nucleon. The precision mapping of TMDs will also allow a detailed study of the quark orbital motion and its dynamics.

Increased rate of arterial stiffening with obesity in adolescents: a five-year follow-up study.

Directory of Open Access Journals (Sweden)

Frida Dangardt

Full Text Available BACKGROUND: We prospectively and longitudinally determined the effects of childhood obesity on arterial stiffening and vascular wall changes. Changes in arterial stiffness measured as pulse wave velocity (PWV and vascular morphology of the radial (RA and dorsal pedal arteries (DPA were examined in obese adolescents compared to lean subjects in a 5-year follow-up study. METHODOLOGY/PRINCIPAL FINDINGS: A total of 28 obese subjects and 14 lean controls participated in both baseline (14 years old and follow-up studies. PWV was measured by tonometer (SphygmoCor® and recorded at RA and carotid artery, respectively. Intima thickness (IT, intima-media thickness (IMT and RA and DPA diameters were measured using high-resolution ultrasound (Vevo 770™. Over the course of 5 years, PWV increased by 25% in the obese subjects as compared to 3% in the controls (p = 0.01. Diastolic blood pressure (DBP increased by 23% in the obese subjects as opposed to 6% in controls (p = 0.009. BMI increased similarly in both groups, as did the IT and IMT. The change in PWV was strongly associated to the baseline BMI z -score (r = 0.51, p<0.001, as was the change in DBP (r = 0.50, p = 0.001. CONCLUSIONS/SIGNIFICANCE: During the transition from early to late adolescence, there was a general increase in arterial stiffness, which was aggravated by childhood obesity. The increase in arterial stiffness and DBP after 5 years was closely correlated to the baseline BMI z -score, indicating that childhood obesity has an adverse impact on vascular adaptation.

Multivariate longitudinal data analysis with mixed effects hidden Markov models.

Science.gov (United States)

Raffa, Jesse D; Dubin, Joel A

2015-09-01

Multiple longitudinal responses are often collected as a means to capture relevant features of the true outcome of interest, which is often hidden and not directly measurable. We outline an approach which models these multivariate longitudinal responses as generated from a hidden disease process. We propose a class of models which uses a hidden Markov model with separate but correlated random effects between multiple longitudinal responses. This approach was motivated by a smoking cessation clinical trial, where a bivariate longitudinal response involving both a continuous and a binomial response was collected for each participant to monitor smoking behavior. A Bayesian method using Markov chain Monte Carlo is used. Comparison of separate univariate response models to the bivariate response models was undertaken. Our methods are demonstrated on the smoking cessation clinical trial dataset, and properties of our approach are examined through extensive simulation studies. © 2015, The International Biometric Society.

Correspondence analysis of longitudinal data

NARCIS (Netherlands)

Van der Heijden, P.G.M.|info:eu-repo/dai/nl/073087998

2005-01-01

Correspondence analysis is an exploratory tool for the analysis of associations between categorical variables, the results of which may be displayed graphically. For longitudinal data with two time points, an analysis of the transition matrix (showing the relative frequencies for pairs of

Longitudinal heritability of childhood aggression

NARCIS (Netherlands)

Porsch, R.M.P.; Middeldorp, C.M.; Cherny, S.S.; Krapohl, E.; van Beijsterveldt, C.E.M.; Loukola, A.; Korhonen, T.; Pulkkinen, L.; Corley, R.P.; Rhee, S.; Kaprio, J.; Rose, R.; Hewitt, J.K.; Sham, P.; Plomin, R.; Boomsma, D.I.; Bartels, M.

2016-01-01

The genetic and environmental contributions to the variation and longitudinal stability in childhood aggressive behavior were assessed in two large twin cohorts, the Netherlands Twin Register (NTR), and the Twins Early Development Study (TEDS; United Kingdom). In NTR, maternal ratings on aggression

Defining SNAP by cross-sectional and longitudinal definitions of neurodegeneration.

Science.gov (United States)

Wisse, L E M; Das, S R; Davatzikos, C; Dickerson, B C; Xie, S X; Yushkevich, P A; Wolk, D A

2018-01-01

Suspected non-Alzheimer's pathophysiology (SNAP) is a biomarker driven designation that represents a heterogeneous group in terms of etiology and prognosis. SNAP has only been identified by cross-sectional neurodegeneration measures, whereas longitudinal measures might better reflect "active" neurodegeneration and might be more tightly linked to prognosis. We compare neurodegeneration defined by cross-sectional 'hippocampal volume' only (SNAP/L-) versus both cross-sectional and longitudinal 'hippocampal atrophy rate' (SNAP/L+) and investigate how these definitions impact prevalence and the clinical and biomarker profile of SNAP in Mild Cognitive Impairment (MCI). 276 MCI patients from ADNI-GO/2 were designated amyloid "positive" (A+) or "negative" (A-) based on their florbetapir scan and neurodegeneration 'positive' or 'negative' based on cross-sectional hippocampal volume and longitudinal hippocampal atrophy rate. 74.1% of all SNAP participants defined by the cross-sectional definition of neurodegeneration also met the longitudinal definition of neurodegeneration, whereas 25.9% did not. SNAP/L+ displayed larger white matter hyperintensity volume, a higher conversion rate to dementia over 5 years and a steeper decline on cognitive tasks compared to SNAP/L- and the A- CN group. SNAP/L- had more abnormal values on neuroimaging markers and worse performance on cognitive tasks than the A- CN group, but did not show a difference in dementia conversion rate or longitudinal cognition. Using a longitudinal definition of neurodegeneration in addition to a cross-sectional one identifies SNAP participants with significant cognitive decline and a worse clinical prognosis for which cerebrovascular disease may be an important driver.

Ozil IP torsional mode versus combined torsional/longitudinal microcoaxial phacoemulsification.

Science.gov (United States)

Helvacioglu, Firat; Tunc, Zeki; Yeter, Celal; Oguzhan, Hasan; Sencan, Sadik

2012-01-01

To compare the safety and efficacy of microcoaxial phacoemulsification surgeries performed with the Ozil Intelligent Phaco (IP) torsional mode and combined torsional/longitudinal ultrasound (US) mode using the Infiniti Vision System (Alcon Laboratories). In this prospective randomized comparative study, 60 eyes were assigned to 2.2-mm microcoaxial phacoemulsification using the Ozil IP torsional mode (group 1) or combined torsional/longitudinal US mode (group 2). The primary outcome measures were US time (UST), cumulative dissipated energy (CDE), longitudinal and torsional ultrasound amplitudes, mean operation time, mean volume of balanced salt solution (BSS) used, and surgical complications. Both groups included 30 eyes. Mean UST, CDE, and longitudinal and torsional ultrasound amplitudes in group 1 were 1 minute 15±34.33 seconds, 8.74±5.64, 0.43±0.74, and 25.56±8.56, respectively, and these parameters in group 2 were 1 minute 40±51.44 seconds, 9.28±5.99, 3.64±1.55, and 3.71±1.34, respectively. UST and longitudinal amplitudes were found to be significantly low in group 1 (p<0.001, p<0.001), whereas torsional amplitude was found to be significantly high in this group (p=0.001). Mean volumes of BSS used in groups 1 and 2 were 63.30±18.00 cc and 84.50±28.65 cc, respectively (p=0.001). The Ozil IP torsional mode may provide more effective lens removal than the combined torsional/longitudinal US mode with a lower UST and volume of BSS used.

Ginger attenuated di (n-butyl phthalate-induced reproductive toxicity in pubertal male rabbits

Directory of Open Access Journals (Sweden)

S. S. Oda

2017-12-01

Full Text Available This study was conducted to investigate the toxic effects of di (n-butyl phthalate (DBP on reproductive functions in male rabbits and the probable protective role of ginger. Twenty rabbits were divided equally into 4 groups: control group; DBP group (520 mg/kg body weight [BW] DBP orally, DBP+ginger group (520 mg/kg BW DBP and 400 mg/kg BW ginger and ginger group (400 mg/kg BW ginger orally. Treatments were given three-times/week. After 7 wk of the experiment, DBP induced significant reduction in testis and prostate weights, serum and intratesticular testosterone concentrations, sperm counts both mass and progressive sperm motility and live sperms percentage as well as significant elevation of testicular malondialdehyde compared to control group. No significant changes were detected in epididymal weights, serum FSH and serum LH concentrations and testicular total superoxide dismutase and glutathione peroxidase activities in all treated groups. DBP induced considerable histopathological alterations in testis and to minimal extent in epididymis and prostates. Ginger treatment attenuated the significant changes to a certain extent induced by DBP intoxication in male rabbits probably due to its potential to scavenge free radicals.

Dynamics of heavy ion beams during longitudinal compression

International Nuclear Information System (INIS)

Ho, D.D.M.; Bangerter, R.O.; Lee, E.P.; Brandon, S.; Mark, J.W.K.

1987-01-01

Heavy ion beams with initially uniform line charge density can be compressed longitudinally by an order of magnitude in such a way that the compressed beam has uniform line charge density and velocity-tilt profiles. There are no envelope mismatch oscillations during compression. Although the transverse temperature varies along the beam and also varies with time, no substantial longitudinal and transverse emittance growth has been observed. Scaling laws for beam radius and transport system parameters are given

Statistical methods for longitudinal data with agricultural applications

DEFF Research Database (Denmark)

Anantharama Ankinakatte, Smitha

The PhD study focuses on modeling two kings of longitudinal data arising in agricultural applications: continuous time series data and discrete longitudinal data. Firstly, two statistical methods, neural networks and generalized additive models, are applied to predict masistis using multivariate...... algorithm. This was found to compare favourably with the algorithm implemented in the well-known Beagle software. Finally, an R package to apply APFA models developed as part of the PhD project is described...

The knowledge of the inhabitants of Lesser Poland about the profession of an occupational therapist

Directory of Open Access Journals (Sweden)

Żmudzińska Urszula Ż

2017-12-01

Full Text Available Introduction: A contemporary model of occupational therapy differs from the previous model which was common in Poland in previous years. Therefore, the opinions of the society concerning the profession of an occupational therapist are constantly changing. Material and methods: The research included 244 inhabitants of Lesser Poland aged between 25 and 65 employed in various professions. A questionnaire regarding occupational therapy and the profession and competences of occupational therapists was applied in the study. Results: The presented results show that the job of an occupational therapist is perceived as a needed profession both by individuals who underwent such therapy and those who did not use such services. Responses regarding competences and activities in the profession of an occupational therapist revealed differences in the opinions of the study participants. Conclusions: Taking into account only competences and activities of an occupational therapist, associations of the study participants reflected the knowledge of the model of therapy that existed before and was mainly devoted to occupational therapy workshops. The respondents would trust an occupational therapist both in adapting the house to their needs and in performing exercises connected with activities of daily living.

Longitudinal and bulk viscosities of expanded rubidium

International Nuclear Information System (INIS)

Zaheri, Ali Hossein Mohammad; Srivastava, Sunita; Tankeshwar, K

2003-01-01

First three non-vanishing sum rules for the bulk and longitudinal stress auto-correlation functions have been evaluated for liquid Rb at six thermodynamic states along the liquid-vapour coexistence curve. The Mori memory function formalism and the frequency sum rules have been used to calculate bulk and longitudinal viscosities. The results thus obtained for the ratio of bulk viscosity to shear viscosity have been compared with experimental and other theoretical predictions wherever available. The values of the bulk viscosity have been found to be more than the corresponding values of the shear viscosity for all six thermodynamic states investigated here

Biodegradation of di-n-butyl phthalate by bacterial consortium LV-1 enriched from river sludge.

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Yangyang Wang

Full Text Available A stable bacterial consortium (LV-1 capable of degrading di-n-butyl phthalate (DBP was enriched from river sludge. Community analysis revealed that the main families of LV-1 are Brucellaceae (62.78% and Sinobacteraceae (14.83%, and the main genera of LV-1 are Brucella spp. (62.78% and Sinobacter spp. (14.83%. The optimal pH and temperature for LV-1 to degrade DBP were pH 6.0 and 30°C, respectively. Inoculum size influenced the degradation ratio when the incubation time was < 24 h. The initial concentration of DBP also influenced the degradation rates of DBP by LV-1, and the degradation rates ranged from 69.0-775.0 mg/l/d in the first 24 h. Degradation of DBP was best fitted by first-order kinetics when the initial concentration was < 300 mg/l. In addition, Cd2+, Cr6+, and Zn2+ inhibited DBP degradation by LV-1 at all considered concentrations, but low concentrations of Pb2+, Cu2+, and Mn2+ enhanced DBP degradation. The main intermediates (mono-ethyl phthalate [MEP], mono-butyl phthalate [MBP], and phthalic acid [PA] were identified in the DBP degradation process, thus a new biochemical pathway of DBP degradation is proposed. Furthermore, LV-1 also degraded other phthalates with shorter ester chains (DMP, DEP, and PA.

Simulation of the longitudinal instabilities of the asymmetric bunches

International Nuclear Information System (INIS)

Dai Jianping; Zhao Zhentang

2002-01-01

The computational model of the code used to simulate the longitudinal instabilities of the asymmetric bunches was introduced. The growth rates of the longitudinal instabilities of the symmetric bunches got by this code were compared with those got by the code ZAP, and they were almost the same. As an example, the simulation results of the BEPC-II were presented

Evaluation of DNA damage and antioxidant system induced by di-n-butyl phthalates exposure in earthworms (Eisenia fetida).

Science.gov (United States)

Du, Li; Li, Guangde; Liu, Mingming; Li, Yanqiang; Yin, Suzhen; Zhao, Jie; Zhang, Xinyi

2015-05-01

Di-n-butyl phthalates (DBP) are recognized as ubiquitous contaminants in soil and adversely impact the health of organisms. The effect of DBP on the activity of antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT), malondialdehyde (MDA) content and DNA damage were used as biomarkers to analyze the relationship between DNA damage and oxidative stress and to evaluate the genotoxic effect of DBP on earthworms (Eisenia fetida). DBP was added to artificial soil in the amounts of 0, 5, 10, 50 and 100mg per kg of soil. Earthworm tissues exposed to each treatment were collected on the 7th, 14th, 21st, and 28th day of the treatment. The results showed that SOD and CAT levels were significantly inhibited in the 100mgkg(-1) treatment group on day 28. MDA content in treatment groups was higher than in the control group throughout the exposure time, suggesting that DBP may lead to oxidative stress in cells. A dose-response relationship existed between DNA damage and total soil DBP levels. The comet assay showed that increasing concentrations of DBP resulted in a gradual increase in the OTM, Comet Tail Length and Tail DNA %. The degree of DNA damage was increased with increasing concentration of DBP. These results suggested that DBP induced serious oxidative damage on earthworms and induced the formation of reactive oxygen species (ROS) in earthworms. The excessive generation of ROS caused damage to vital macromolecules including lipids and DNA. DBP in the soils were responsible for the exerting genotoxic effects on earthworms. Copyright © 2015 Elsevier Inc. All rights reserved.

Longitudinal Bunch Position Control for the Super-B Accelerator

International Nuclear Information System (INIS)

Bertsche, Kirk; Rivetta, Claudio; Sullivam, Michael K.; SLAC; Drago, Alessandro; Frascati

2009-01-01

The use of normal conducting cavities and an ion-clearing gap will cause a significant RF accelerating voltage gap transient and longitudinal phase shift of the individual bunches along the bunch train in both rings of the SuperB accelerator. Small relative centroid position shifts between bunches of the colliding beams will have a large adverse impact on the luminosity due to the small β* y at the interaction point (IP). We investigate the possibility of minimizing the relative longitudinal position shift between bunches by reducing the gap transient in each ring and matching the longitudinal bunch positions of the two rings at the IP using feedback/feedforward techniques in the LLRF. The analysis is conducted assuming maximum use of the klystron power installed in the system

Longitudinal Jitter Analysis of a Linear Accelerator Electron Gun

Directory of Open Access Journals (Sweden)

MingShan Liu

2016-11-01

Full Text Available We present measurements and analysis of the longitudinal timing jitter of a Beijing Electron Positron Collider (BEPCII linear accelerator electron gun. We simulated the longitudinal jitter effect of the gun using PARMELA to evaluate beam performance, including: beam profile, average energy, energy spread, and XY emittances. The maximum percentage difference of the beam parameters is calculated to be 100%, 13.27%, 42.24% and 65.01%, 86.81%, respectively. Due to this, the bunching efficiency is reduced to 54%. However, the longitudinal phase difference of the reference particle was 9.89°. The simulation results are in agreement with tests and are helpful to optimize the beam parameters by tuning the trigger timing of the gun during the bunching process.

Longitudinal transport measurements in an energy recovery accelerator with triple bend achromat arcs

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F. Jackson

2016-12-01

Full Text Available Longitudinal properties of electron bunches (energy spread and bunch length and their manipulation are of importance in free electron lasers (FELs, where magnetic bunch length compression is a common feature of beam transport. Recirculating accelerators and energy recovery linac accelerators (ERLs have been used as FEL drivers for several decades and control of longitudinal beam transport is particularly important in their magnet lattices. We report on measurements of longitudinal transport properties in an ERL-FEL, the ALICE (Accelerators and Lasers in Combined Experiments accelerator at Daresbury Laboratory. ALICE is an energy recovery research accelerator that drives an infrared free electron laser. By measuring the time of arrival of electron bunches, the canonical longitudinal transport quantities were measured in the beam transport and bunch compression sections of the lattice. ALICE includes a four-dipole bunch compression chicane providing fixed longitudinal transport, and triple bend achromat arcs including sextupole magnets where the first and second order longitudinal transport can be adjusted. The longitudinal transport properties in these lattice sections were measured and compared with the theoretical model of the lattice. A reasonable level of agreement has been found. The effect of sextupoles in second order, as well as first order, longitudinal correction is considered, with the measurements indicating the level of alignment of the beam to the center of the sextupole.

Prevalence and risk factors of hypertension for the middle-aged population in China - results from the China Health and Retirement Longitudinal Study (CHARLS).

Science.gov (United States)

Li, Zhen; Fu, Chang; Yang, Fan; Mao, Zongfu

2018-03-19

The prevalence of hypertension in middle-aged people is increasing. However, few studies have examined the risk factors of hypertension among the middle-aged population. The aim of this study is to present the prevalence of hypertension and its risk factors for the middle-aged population in China. The data were from the third-wave national survey (2015) of the China Health and Retirement Longitudinal Study (CHARLS). A total of 7,178 respondents aged 45-59 years were included in this study. Hypertension was defined as SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg or currently taking antihypertensive medicines. Multivariate logistic regression analyses were used to identify the risk factors of hypertension. The prevalence of hypertension was 29.12% (95%CI = 28.07-30.17). Hypertension was more prevalent among men than women (31.63% vs. 27.03%). Older age, higher BMI, chronic diseases, and poor health status were independently associated with hypertension in both genders (p < 0.05). Among women, college education (OR = 0.302, 95%CI = 0.152-0.598), marriage or cohabitation (OR = 0.756, 95%CI = 0.584-0.98), and drinking more than once a month (OR = 0.645, 95% = 0.498-0.836) led to a decreased likelihood of hypertension. Individuals with larger waist circumference were more likely to have hypertension (OR = 1.57, 95%CI = 1.294-1.906). Our results indicate that hypertension is highly prevalent in the middle-aged population in China. Men are more likely to have hypertension than women. Older age, higher BMI, chronic diseases and poor self-rated health are risk factors for hypertension in both genders. Large waist circumference, singleness, low educational level, and non-drinking are risk factors of hypertension among women but not among men.

Enhanced ozonation degradation of di-n-butyl phthalate by zero-valent zinc in aqueous solution: Performance and mechanism

Energy Technology Data Exchange (ETDEWEB)

Wen, Gang [School of Environmental and Municipal Engineering, Xi’an University of Architecture and Technology, Xi’an 710050 (China); State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Wang, Sheng-Jun [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Beijing General Municipal Engineering Design and Research Institute, Beijing 100082 (China); Ma, Jun, E-mail: majun@hit.edu.cn [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Huang, Ting-Lin [School of Environmental and Municipal Engineering, Xi’an University of Architecture and Technology, Xi’an 710050 (China); Liu, Zheng-Qian, E-mail: liuzhengqian@gmail.com [School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Zhao, Lei [School of Civil Engineering, Harbin Institute of Technology, Harbin 150090 (China); Su, Jun-Feng [State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC), Tsinghua University, Beijing 100084 (China)

2014-01-30

Highlights: • ZVZ showed an obvious enhanced effect on DBP degradation in ozonation. • The recycling use of ZVZ resulted in the enhancement of DBP degradation. • The formed ZnO and reactive intermediates were responsible for the enhanced effect. • The enhanced effect on DBP degradation by ZVZ was also effective in actual waters. -- Abstract: Enhanced ozonation degradation of di-n-butyl phthalate (DBP) by zero-valent zinc (ZVZ) has been investigated using a semi-continuous reactor in aqueous solution. The results indicated that the combination of ozone (O{sub 3}) and ZVZ showed an obvious synergetic effect, i.e. an improvement of 54.8% on DBP degradation was obtained by the O{sub 3}/ZVZ process after 10 min reaction compared to the cumulative effect of O{sub 3} alone and O{sub 2}/ZVZ. The degradation efficiency of DBP increased gradually with the increase of ZVZ dosage, enhanced as solution pH increasing from 2.0 to 10.0, and more amount of DBP was degraded with the initial concentration of DBP arising from 0.5 to 2.0 mg L{sup −1}. Recycling use of ZVZ resulted in the enhancement of DBP degradation, because the newly formed zinc oxide took part in the reaction. The mechanism investigation demonstrated that the enhancement effect was attributed to the introduction of ZVZ, which could promote the utilization of O{sub 3}, enhance the formation of superoxide radical by reducing O{sub 2} via one-electron transfer, accelerate the production of hydrogen peroxide and the generation of hydroxyl radical. Additionally, the newly formed zinc oxide on ZVZ surface also contributed to the enhancement of DBP degradation in the recycling use of ZVZ. Most importantly, the O{sub 3}/ZVZ process was also effective in enhanced ozonation degradation of DBP under the background of actual waters.

Is the area under blood pressure curve the best parameter to evaluate 24-h ambulatory blood pressure monitoring data?

Science.gov (United States)

Nobre, Fernando; Mion, Décio

2005-10-01

Ambulatory blood pressure monitoring (ABPM) provides relevant data about blood pressure over a 24-h period. The analysis of parameters to determine the blood pressure profile from these data is of great importance. To calculate areas under systolic and diastolic blood pressure curves (SBP-AUC/DBP-AUC) and compare with systolic and diastolic blood pressure load (SBPL/DBPL) and 24-h systolic and diastolic blood pressure (24-h SBP/24-h DBP) in order to determine which provides the best correlation with left ventricular mass index (LVMI). ABPM measurements (1143 individuals) were analyzed to obtain 24-h SBP/24-h DBP, SBPL/DBPL, and SBP-AUC/ DBP-AUC, using Spacelabs (90207) and CardioSistemas devices. Left ventricular mass was determined using an echocardiograph HP Sonos 5500 and LVMI was calculated. The correlations between all possible pairs within the group 24-h SBP/SBPL/SBP-AUC and 24-h DBP/DBPL/DBP-AUC were high and statistically significant. The correlations between 24-h SBP/24-h DBP and SBP-AUC/DBP-AUC with SBPL/DBPL close to 100%, were lower than those mentioned above. The correlations of the parameters obtained by ABPM with LVMI were also high and statistically significant, except for blood pressure load between 90 and 100%, and for 24-h SBP of 135 mmHg or less and SBPL higher than 50%. SBPL/DBPL and SBP-AUC/DBP-AUC can be used for the evaluation of ABPM data owing to the strong correlation with 24-h SBP/24-h DBP and with LVMI, except when SBPL is close to 100% or 24-h SBP is below 135 mmHg but SBPL is above 50%. SBP-AUC/DBP-AUC, however, are a better alternative because they do not have the limitations of blood pressure load or even of 24-h blood pressure present.

High intensity interior aircraft noise increases the risk of high diastolic blood pressure in Indonesian Air Force pilots

Directory of Open Access Journals (Sweden)

Minarma Siagian

2009-12-01

Full Text Available Aim: To analyze the effects of aircraft noise, resting pulse rate, and other factors on the risk of high diastolic blood pressure (DBP in Indonesian Air Force pilots.Methods: A nested case-control study was conducted using data extracted from annual medical check-ups indoctrination aerophysiologic training records at the Saryanto Aviation and Aerospace Health Institute (LAKESPRA in Jakarta from January 2003 – September 2008. For analysis of DBP: the case group with DBP ≥ 90 mmHg were compared with contral group with DBP < 79 mmHG. One case matched to 12 controls.Results: Out of 567 pilots, 544 (95.9% had complete medical records. For this analysis there were 40 cases of high DBP and 480 controls for DBP. Pilots exposed to aircraft noise 90-95 dB rather than 70-80 dB had a 2.7-fold increase for high DBP [adjusted odds ratio (ORa = 2.70; 95% confi dence interval (CI = 1.05-6.97]. Pilots with resting pulse rates of ≥ 81/minute rather than ≤ 80/minute had a 2.7-fold increase for high DBP (ORa = 2.66; 95% CI = 1.26-5.61. In terms of total fl ight hours, pilots who had 1401-11125 hours rather than 147-1400 hours had a 3.2-fold increase for high DBP (ORa = 3.18; 95% CI = 1.01-10.03.Conclusion: High interior aircraft noise, high total flight hours,  and high resting pulse rate, increased risk for high DBP. Self assessment of resting pulse rate can be used to control the risk of high DBP. (Med J Indones 2009; 276: 276-82Keywords: diastolic blood pressure, aircraft noise, resting pulse rate, military pilots

First record of the Lesser Horseshoe bat, Rhinolophus hipposideros (Bechstein, 1800 (Rhinolophidae, Chiroptera from Syria

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Adwan Shehab

2006-09-01

Full Text Available Abstract The lesser horseshoe bat Rhinolophus hipposideros was recorded for the first time from Syria in 2005-06. Two solitary hibernating specimens (a male and a female were collected from an underground cave in Basofan village, NW of Aleppo, and from Al Marqab Citadel, Banyas. External and cranial measurements are given for both specimens. The list of recorded species of bats of Syria includes 17 species. Riassunto Prima segnalazione di Rinolofo minore Rhinolophus hipposideros (Bechstein, 1800 (Rhinolophidae, Chiroptera in Siria La specie è stata rinvenuta nel 2005-06 con il ritrovamento di due esemplari solitari ibernanti (un maschio e una femmina, rispettivamente in una grotta presso il paese di Basofan, NO di Aleppo e in Al Marqab, Banyas. Per entrambi gli esemplari sono riportate le misure craniali e esterne. Con il ritrovamento del Rinolofo minore la chirotterofauna della Siria è attualmente rappresentata da 17 specie.

Learning from Longitudinal Research in Criminology and the Health Sciences

Science.gov (United States)

Vanderstaay, Steven L.

2006-01-01

This article reviews longitudinal research within criminology and the health sciences on the relationship between reading and criminal, delinquent, or antisocial behavior. Longitudinal research in criminology, medicine, and psychology examines the role of reading within a broad set of interactive processes, connecting literacy to public health via…

Longitudinal person-related determinants of physical activity in young adults.

NARCIS (Netherlands)

Uijtdewilligen, L.; Twisk, J.W.R.; Chinapaw, M.J.M.; Koppes, L.L.J.; Mechelen, W. van; Singh, A.S.

2014-01-01

Purpose: This study aimed to examine the longitudinal associations of person-related factors with physical activity (PA) behavior in young adults. Methods: We analyzed longitudinal self-reported time spent in moderate-intensity PA (MPA; 4–7 METs) and vigorous-intensity PA (VPA; >7 METs) from 499

Longitudinal Person-Related Determinants of Physical Activity in Young Adults

NARCIS (Netherlands)

Uijtdewilligen, L.; Twisk, J.W.R.; Chin A Paw, M.J.M.; Koppes, L.L.J.; van Mechelen, W.; Singh, A.S.

2014-01-01

Purpose: This study aimed to examine the longitudinal associations of person-related factors with physical activity (PA) behavior in young adults. Methods: We analyzed longitudinal self-reported time spent in moderate-intensity PA (MPA; 4-7 METs) and vigorous-intensity PA (VPA; >7 METs) from 499

Longitudinal person-related determinants of physical activity in young adults

NARCIS (Netherlands)

Uijtdewilligen, L.; Twisk, J.W.R.; Chinapaw, M.J.M.; Koppes, L.L.J.; Mechelen, W. van; Singh, A.S.

2014-01-01

Purpose: This study aimed to examine the longitudinal associations of person-related factors with physical activity (PA) behavior in young adults. Methods: We analyzed longitudinal self-reported time spent in moderate-intensity PA (MPA; 4-7 METs) and vigorous-intensity PA (VPA; >7 METs) from 499

A longitudinal study

OpenAIRE

Kristen, Astrid

2010-01-01

Does playing violent video games increase aggressive behavior over time or is it aggressive children who increasingly seek out (and play) these violent video games? To study such long-term effects a longitudinal design is necessary. Within a field study in a large German city (Kinder, Computer, Hobby, Lernen – KUHL, Freie Universtität Berlin) about 115 elementary school boys attending in the beginning (t1) classrooms of the third and fourth grade and twelve months later (t2) classrooms of the...

Documentary-derived chronologies of rainfall variability in Antigua, Lesser Antilles, 1770–1890

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A. J. Berland

2013-06-01

Full Text Available This paper presents the first extensive reconstruction of precipitation variability in the Lesser Antilles using historical documentary sources. Over 13 250 items of documentation pertaining to Antigua from the period 1769–1890 were consulted, including missionary, plantation and governmental papers as well as contemporary scholarly publications. Based on the predominant meteorological conditions observed throughout the island, each "rain-year" (December–November was assigned one of five classifications (very wet, wet, "normal", dry and very dry. Local weather references relating to seven plantations in central-eastern Antigua were grouped according to dry (December–April and wet seasons (May–November, each of which were also categorised in the aforementioned manner. Results comprise individual island-wide and central-eastern Antiguan chronologies of relative precipitation levels, spanning the rain-years 1769–70 to 1889–90 and 1769–70 to 1853–54 respectively. The former is compared with available instrumental data for the years 1870–1890. Significant dry phases are identified in the rain-years 1775–80, 1788–91, 1820–22, 1834–37, 1844–45, 1859–60, 1862–64, 1870–74 and 1881–82, while wet episodes were 1771–74, 1833–34, 1837–38, 1841–44, 1845–46 and 1878–81. Evidence for major wet and dry spells is presented and findings are evaluated within wider historical and palaeoclimatic contexts.

Nonlinear correction to the longitudinal structure function at small x

International Nuclear Information System (INIS)

Boroun, G.R.

2010-01-01

We computed the longitudinal proton structure function F L , using the nonlinear Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (NLDGLAP) evolution equation approach at small x. For the gluon distribution, the nonlinear effects are related to the longitudinal structure function. As the very small-x behavior of the gluon distribution is obtained by solving the Gribov, Levin, Ryskin, Mueller and Qiu (GLR-MQ) evolution equation with the nonlinear shadowing term incorporated, we show that the strong rise that corresponds to the linear QCD evolution equations can be tamed by screening effects. Consequently, the obtained longitudinal structure function shows a tamed growth at small x. We computed the predictions for all details of the nonlinear longitudinal structure function in the kinematic range where it has been measured by the H1 Collaboration and made comparisons with the computation by Moch, Vermaseren and Vogt at the second order with input data from the MRST QCD fit. (orig.)

Association between mutation spectra and stable and unstable DNA adduct profiles in Salmonella for benzo[a]pyrene and dibenzo[a,l]pyrene

Energy Technology Data Exchange (ETDEWEB)

DeMarini, David M., E-mail: demarini.david@epa.gov [Integrated Systems Toxicology Division, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Hanley, Nancy M.; Warren, Sarah H.; Adams, Linda D.; King, Leon C. [Integrated Systems Toxicology Division, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States)

2011-09-01

Highlights: {yields} Benzo[a]pyrene (BP) induces stable DNA adducts and mutations primarily at guanine. {yields} Dibenzo[a,l]pyrene (DBP) induces them primarily at adenine. {yields} BP induces abasic sites, but DBP does not in the Salmonella mutagenicity assay. {yields} Stable DNA adducts alone appear to account for the mutation spectrum of DBP. {yields} Stable DNA adducts and possibly abasic sites account for the mutation spectrum of BP. - Abstract: Benzo[a]pyrene (BP) and dibenzo[a,l]pyrene (DBP) are two polycyclic aromatic hydrocarbons (PAHs) that exhibit distinctly different mutagenicity and carcinogenicity profiles. Although some studies show that these PAHs produce unstable DNA adducts, conflicting data and arguments have been presented regarding the relative roles of these unstable adducts versus stable adducts, as well as oxidative damage, in the mutagenesis and tumor-mutation spectra of these PAHs. However, no study has determined the mutation spectra along with the stable and unstable DNA adducts in the same system with both PAHs. Thus, we determined the mutagenic potencies and mutation spectra of BP and DBP in strains TA98, TA100 and TA104 of Salmonella, and we also measured the levels of abasic sites (aldehydic-site assay) and characterized the stable DNA adducts ({sup 32}P-postlabeling/HPLC) induced by these PAHs in TA104. Our results for the mutation spectra and site specificity of stable adducts were consistent with those from other systems, showing that DBP was more mutagenic than BP in TA98 and TA100. The mutation spectra of DBP and BP were significantly different in TA98 and TA104, with 24% of the mutations induced by BP in TA98 being complex frameshifts, whereas DBP produced hardly any of these mutations. In TA104, BP produced primarily GC to TA transversions, whereas DBP produced primarily AT to TA transversions. The majority (96%) of stable adducts induced by BP were at guanine, whereas the majority (80%) induced by DBP were at adenine

Longitudinal tracking with phase and amplitude modulated rf

International Nuclear Information System (INIS)

Caussyn, D.D.; Ball, M.; Brabson, B.

1993-06-01

Synchrotron motion was induced by phase shifting the rf of the Indiana University Cyclotron Facility (IUCF) cooler-synchrotron. The resulting coherent-bunch motion was tracked in longitudinal phase space for as many as 700,000 turns, or for over 350 synchrotron oscillations. Results of recent experimental studies of longitudinal motion in which the rf phase and amplitude were harmonically modulated are also presented. Comparisons of experimental data with numerical simulations, assuming independent particle motion, are made. Observed multiparticle effects are also discussed

Single bunch fast longitudinal instability

International Nuclear Information System (INIS)

Wang, J.M.; Pellegrini, C.

1979-01-01

Single bunch longitudinal instability producing an increase of the bunch area have been observed in proton synchrotron and storage rings. Signals at microwave frequencies are observed during the bunch blow-up and because of this the effect has been called the microwave instability. A similar increase in bunch area is observed also in electron storage rings, where it is usually referred to as the bunch lengthening effect. This paper is an attempt to obtain a more general theory of this effect. Here we describe the model used and the method of calculation, together with some general results. More detailed results will be given in another paper. The main result is the derivation of a condition for the existence of a fast longitudinal bunch blow-up. This condition is a generalized threshold formula, showing explicitly the dependence on the bunch energy spread and length. This condition is qualitatively in agreement with Boussard's suggestion

Longitudinal emittance blowup in the large hadron collider

CERN Document Server

Baudrenghien, P

2013-01-01

The Large Hadron Collider (LHC) relies on Landau damping for longitudinal stability. To avoid decreasing the stability margin at high energy, the longitudinal emittance must be continuously increased during the acceleration ramp. Longitudinal blowup provides the required emittance growth. The method was implemented through the summer of 2010. Band-limited RF phase-noise is injected in the main accelerating cavities during the whole ramp of about 11min. Synchrotron frequencies change along the energy ramp, but the digitally created noise tracks the frequency change. The position of the noise-band, relative to the nominal synchrotron frequency, and the bandwidth of the spectrum are set by pre-defined constants, making the diffusion stop at the edges of the demanded distribution. The noise amplitude is controlled by feedback using the measurement of the average bunch length. This algorithm reproducibly achieves the programmed bunch length of about 1.2ns, at flat top with low bunch-to-bunch scatter and provides a...

A Semiparametric Marginalized Model for Longitudinal Data with Informative Dropout

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Mengling Liu

2012-01-01

Full Text Available We propose a marginalized joint-modeling approach for marginal inference on the association between longitudinal responses and covariates when longitudinal measurements are subject to informative dropouts. The proposed model is motivated by the idea of linking longitudinal responses and dropout times by latent variables while focusing on marginal inferences. We develop a simple inference procedure based on a series of estimating equations, and the resulting estimators are consistent and asymptotically normal with a sandwich-type covariance matrix ready to be estimated by the usual plug-in rule. The performance of our approach is evaluated through simulations and illustrated with a renal disease data application.

Sequential Progressions in a Theory-of-Mind Scale: Longitudinal Perspectives

Science.gov (United States)

Wellman, Henry M.; Fang, Fuxi; Peterson, Candida C.

2011-01-01

Consecutive retestings of 92 U.S. preschoolers (n = 30), Chinese preschoolers (n = 31), and deaf children (n = 31) examined whether the sequences of development apparent in cross-sectional results with a theory-of-mind scale also appeared in longitudinal assessment. Longitudinal data confirmed that theory-of-mind progressions apparent in…

Boosting joint models for longitudinal and time-to-event data

DEFF Research Database (Denmark)

Waldmann, Elisabeth; Taylor-Robinson, David; Klein, Nadja

2017-01-01

Joint models for longitudinal and time-to-event data have gained a lot of attention in the last few years as they are a helpful technique clinical studies where longitudinal outcomes are recorded alongside event times. Those two processes are often linked and the two outcomes should thus be model...

Nonlinear Cascade Strategy for Longitudinal Control of Electric Vehicle.

Science.gov (United States)

El Majdoub, K; Giri, F; Ouadi, H; Chaoui, F Z

2014-01-01

The problem of controlling the longitudinal motion of front-wheels electric vehicle (EV) is considered making the focus on the case where a single dc motor is used for both front wheels. Chassis dynamics are modelled applying relevant fundamental laws taking into account the aerodynamic effects and the road slope variation. The longitudinal slip, resulting from tire deformation, is captured through Kiencke's model. Despite its highly nonlinear nature the complete model proves to be utilizable in longitudinal control design. The control objective is to achieve a satisfactory vehicle speed regulation in acceleration/deceleration stages, despite wind speed and other parameters uncertainty. An adaptive controller is developed using the backstepping design technique. The obtained adaptive controller is shown to meet its objectives in presence of the changing aerodynamics efforts and road slope.

Structure functions of longitudinal virtual photons at low virtualities

International Nuclear Information System (INIS)

Ioffe, B.L.; Shushpanov, I.A.

1996-01-01

The structure functions F L 1 and F L 2 of longitudinal virtual photons at low virtualities are calculated in the framework of chiral perturbation theory (ChPT) in the zero and first order of ChPT. It is assumed that the virtuality of a target longitudinal photon p 2 is much less than the virtuality of the hard projectile photon Q 2 and both are less than the characteristic ChPT scale. In this approximation the structure functions are determined by the production of two pions in γγ collisions. The numerical results for F L 2 and F L 1 are presented (the upper index refers to the longitudinal polarization of the virtual target photon). The possibilities of measurements of these structure functions are briefly discussed. copyright 1996 The American Physical Society

Multilevel Cross-Dependent Binary Longitudinal Data

KAUST Repository

Serban, Nicoleta; Staicu, Ana-Maria; Carroll, Raymond J.

2013-01-01

processes describing the within- and between-variability, and describing the cross-dependence of the repeated longitudinal measurements. We estimate the model components without employing mixed-effects modeling but assuming an approximation to the logistic

Frequent Daytime Naps Predict Vocabulary Growth in Early Childhood

Science.gov (United States)

Horváth, Klára; Plunkett, Kim

2016-01-01

Background: The facilitating role of sleep for language learning is well-attested in adults and to a lesser extent in infants and toddlers. However, the longitudinal relationship between sleep patterns and early vocabulary development is not well understood. Methods: This study investigates how measures of sleep are related to the development of…

The Subduction of an Exhumed and Serpentinized Magma-Poor Basement Beneath the Northern Lesser Antilles Reveals the Early Tectonic Fabric at Slow-Spreading Mid-Oceanic Ridges

Science.gov (United States)

Marcaillou, B.; Klingelhoefer, F.; Laurencin, M.; Biari, Y.; Graindorge, D.; Jean-Frederic, L.; Laigle, M.; Lallemand, S.

2017-12-01

Multichannel and wide-angle seismic data as well as heat-flow measurements (ANTITHESIS cruise, 2016) reveal a 200x200km patch of magma-poor oceanic basement in the trench and beneath the outer fore-arc offshore of Antigua to Saint Martin in the Northern Lesser Antilles. These data highlight an oceanic basement with the following features: 1/ Absence of any reflection at typical Moho depth and layer2/layer3 limit depths. 2/ High Velocity Vp at the top (>5.5 km/s), low velocity gradient with depth (serpentinized at the slow-spreading mid-Atlantic Ridge 80 Myr ago, is currently subducting beneath the Northern Lesser Antilles. During the exhumation, early extension triggers penetrative shear zones sub-parallel to the ridge and to the transform fault. Eventually, this early extension generates sliding along the so-called detachment fault, while the other proto-detachment abort. Approaching the trench, the plate bending reactivates these weak zones in normal faults and fluid pathways promoting deep serpentinisation and localizing tectonic deformation at the plate interface. These subducting fluid-rich mechanically weak mantle rocks rise questions about their relation to the faster slab deepening, the lower seismic activity and the pervasive tectonic partitioning in this margin segment.

Estimating correlation between multivariate longitudinal data in the presence of heterogeneity.

Science.gov (United States)

Gao, Feng; Philip Miller, J; Xiong, Chengjie; Luo, Jingqin; Beiser, Julia A; Chen, Ling; Gordon, Mae O

2017-08-17

Estimating correlation coefficients among outcomes is one of the most important analytical tasks in epidemiological and clinical research. Availability of multivariate longitudinal data presents a unique opportunity to assess joint evolution of outcomes over time. Bivariate linear mixed model (BLMM) provides a versatile tool with regard to assessing correlation. However, BLMMs often assume that all individuals are drawn from a single homogenous population where the individual trajectories are distributed smoothly around population average. Using longitudinal mean deviation (MD) and visual acuity (VA) from the Ocular Hypertension Treatment Study (OHTS), we demonstrated strategies to better understand the correlation between multivariate longitudinal data in the presence of potential heterogeneity. Conditional correlation (i.e., marginal correlation given random effects) was calculated to describe how the association between longitudinal outcomes evolved over time within specific subpopulation. The impact of heterogeneity on correlation was also assessed by simulated data. There was a significant positive correlation in both random intercepts (ρ = 0.278, 95% CI: 0.121-0.420) and random slopes (ρ = 0.579, 95% CI: 0.349-0.810) between longitudinal MD and VA, and the strength of correlation constantly increased over time. However, conditional correlation and simulation studies revealed that the correlation was induced primarily by participants with rapid deteriorating MD who only accounted for a small fraction of total samples. Conditional correlation given random effects provides a robust estimate to describe the correlation between multivariate longitudinal data in the presence of unobserved heterogeneity (NCT00000125).

[The effects of di-n-butyl phthalate on the somatic cells of laboratory mice].

Science.gov (United States)

Dobrzyńska, Małgorzata M; Tyrkiel, Ewa J; Hernik, Agnieszka; Derezińska, Edyta; Góralczyk, Katarzyna; Ludwicki, Jan K

2010-01-01

Phthalates are widely used as a plasticizers in manufacture of synthetic materials and as solvents in sanitary products, cosmetics and pharmaceutical products. Dibutylphthalate (DBP) is used as a plasticizers and as a textile lubricating agent and as solvent in printing ink. The study aimed the evaluation of the magnitude of DNA damage in liver and bone marrow cells and estimation of dibutyl phthalate (DBP) concentration in peripheral blood following prolonged exposure to DBP. Experiments were conducted an the Pzh:Sfis male mice. Animals were exposed 8 weeks, 3 days per week per os to DBP suspension in oil in doses of 500 mg/kg bw (1/16 LD50) and 2000 mg/kg bw (1/4 LD50). Following groups of mice were sacrificed 4 and 8 weeks after the start of exposure and 4 weeks after the end of exposure. Decreased body weight of mice and statistically significant decreased liver and relative liver weights were observed following 8-weeks exposure to 2000 mg/kg bw DBP. In the same time higher however not statistically significant level of DNA damage measured by Comet assay in liver cells were noted. DBP did not induce enhanced frequency of DNA damage in bone marrow cells. Following 8-weeks exposure to the dose of 2000 mg/kg bw DBP the increased level of DBP in peripheral blood was observed. Enhanced levels of DBP were still noted 4 weeks after the termination of exposure. Results confirmed that DBP acts as a weak mutagen for DNA of somatic cells. However, following prolonged exposure this compound seems to undergo slower metabolism and was reaching temporarily higher levels in peripheral blood.

Recovery of uranium from 30 vol % tributyl phosphate solvents containing dibutyl phosphate

International Nuclear Information System (INIS)

Mailen, J.C.; Tallent, O.K.

1986-01-01

A number of solid sorbents were tested for the removal of uranium and dibutyl phosphate (DBP) from 30% tributyl phosphate (TBP) solvent. The desired clean uranium product can be obtained either by removing the DBP, leaving the uranium in the solvent for subsequent stripping, or by removing the uranium, leaving the DBP in the solvent for subsequent treatment. The tests performed show that it is relatively easy to preferentially remove uranium from solvents containing uranium and DBP, but quite difficult to remove DBP preferentially. The current methods could be used by removing the uranium (as by a cation exchange resin) and then using either an anion exchange resin in the hydroxyl form or a conventional treatment with a basic solution to remove the DBP. Treatment of a solvent with a cation exchange resin could be useful for recovery of valuable metals from solvents containing DBP and might be used to remove cations before scrubbing a solvent with a basic solution to minimize emulsion formation. 6 refs., 9 figs

Sulforaphane attenuates di-N-butylphthalate-induced reproductive damage in pubertal mice: Involvement of the Nrf2-antioxidant system.

Science.gov (United States)

Jiang, Xu-Ping; Tang, Jing-Yuan; Xu, Zhen; Han, Peng; Qin, Zhi-Qiang; Yang, Cheng-di; Wang, Shang-Qian; Tang, Min; Wang, Wei; Qin, Chao; Xu, Yang; Shen, Bai-Xin; Zhou, Wei-Min; Zhang, Wei

2017-07-01

di-N-butylphthalate (DBP) is a ubiquitous environmental pollutant used for plastic coating and in the cosmetics industry. It has toxic effects on body health, especially the male reproductive system. Here, we investigated the effects of DBP on the male reproductive system of pubertal mice and explored the protective role of sulforaphane (SFN). The results showed that DBP significantly reduced the anogenital distance, testicular weight, sperm count and motility, and plasma and testicular testosterone levels and significantly increased the oxidative stress, sperm abnormalities, and testicular cell apoptosis. SFN supplementation ameliorated these effects. After DBP stimulation, the transcription factor nuclear factor erythroid-related factor 2 (Nrf2) was adaptively increased together with its target genes, such as HO-1 and NQO1. Upregulation of Nrf2 by SFN reduced the DBP-mediated intracellular oxidative toxicity and also increased testosterone secretion and spermatogenesis, which were decreased by DBP. These findings indicate that SFN can attenuate DBP-induced reproductive damage in pubertal mice via Nrf2-associated pathways. © 2017 Wiley Periodicals, Inc.

Characterization of soluble microbial products as precursors of disinfection byproducts in drinking water supply.

Science.gov (United States)

Liu, Jin-Lin; Li, Xiao-Yan; Xie, Yue-Feng; Tang, Hao

2014-02-15

Water pollution by wastewater discharge can cause the problem of disinfection byproducts (DBPs) in drinking water supply. In this study, DBP formation characteristics of soluble microbial products (SMPs) as the main products of wastewater organic biodegradation were investigated. The results show that SMPs can act as DBP precursors in simulated wastewater biodegradation process. Under the experimental conditions, stabilized SMPs had DBPFP (DBP formation potential) yield of around 5.6 μmol mmol(-1)-DOC (dissolved organic carbon) and DBP speciation profile different from that of the conventional precursor, natural organic matter (NOM). SMPs contained polysaccharides, proteins, and humic-like substances, and the latter two groups can act as reactive DBP precursors. SMP fraction with molecular weight of water treatment processes, more efforts are needed to control wastewater-derived DBP problem in water resource management. Copyright © 2013 Elsevier B.V. All rights reserved.

Longitudinal permittivity of a toroidal plasma near rational surfaces

International Nuclear Information System (INIS)

Nekrasov, F.M.

1990-01-01

A quite simple analytical formula for longitudinal permittivity, suitable for numerical processing on a computer, is determined. On the basis of a Fourier representation a poloidal angle a compact expression for the imaginary part of longitudinal permittivity near rational surfaces (m+nq=0) at an arbitrary relation between the bounce frequency and excited wave frequency is determined. A strongly magnetized collisionless plasma in the weak toroidality approximation is considered

Causal mediation analysis for longitudinal data with exogenous exposure

OpenAIRE

Bind, M.-A. C.; Vanderweele, T. J.; Coull, B. A.; Schwartz, J. D.

2015-01-01

Mediation analysis is a valuable approach to examine pathways in epidemiological research. Prospective cohort studies are often conducted to study biological mechanisms and often collect longitudinal measurements on each participant. Mediation formulae for longitudinal data have been developed. Here, we formalize the natural direct and indirect effects using a causal framework with potential outcomes that allows for an interaction between the exposure and the mediator. To allow different type...

Longitudinal waves and a beam instability in a relativistic anisotropic plasma

International Nuclear Information System (INIS)

Onishchenko, O.G.

1981-01-01

Dispersion relations are derived for longitudinal waves in a relativistic plasma with an arbitrary anisotropic particle distribution function. Longitudinal waves with phase velocity lower than the speed of light are shown to exist in such a plasma. The damping rate of longitudinal waves due to the Cerenkov interaction with plasma particles is derived for such a plasma. The instability of a beam of high-energy particles in such a plasma is studied. As the anisotropy of an ultrarelativistic plasma becomes less pronounced, the maximum hydrodynamic growth rate decreases

Forage digestibility and intake by lesser snow geese: effects of dominance and resource heterogeneity

Science.gov (United States)

Hupp, Jerry W.; White, Robert G.; Sedinger, James S.; Robertson, Donna G.

1996-01-01

We measured forage intake, digestibility, and retention time for 11 free-ranging, human-imprinted lesser snow geese (Chen caerulescens caerulescens) as they consumed underground stembases of tall cotton-grass (Eriophorum angustifolium) on an arctic staging area in northeastern Alaska. Geese fed in small patches (x̄=21.5 m2) of forage that made up ≤3% of the study area and consisted of high-quality “aquatic graminoid” and intermediate-quality “wet sedge” vegetation types. Dominant geese spent more time feeding in aquatic graminoid areas (r=0.61), but less total time feeding and more time resting than subdominant geese. Subdominant geese were displaced to areas of wet sedge where cotton-grass was a smaller proportion of underground biomass. Geese metabolized an average of 48% of the organic matter in stembases and there was a positive correlation between dominance and organic matter metabolizability (r=0.61). Total mean retention time of forage was 1.37 h and dry matter intake was 14.3 g/h. Snow geese that stage on the coastal plain of the Beaufort Sea likely use an extensive area because they consume a large mass of forage and exploit habitats that are patchily distributed and make up a small percentage of the landscape. Individual variation in nutrient absorption may result from agonistic interactions in an environment where resources are heterogeneously distributed.

Electrophysiology and Innervation of the Photosensitive Epistellar Body in the Lesser Octopus Eledone cirrhosa.

Science.gov (United States)

Cobb, C S; Williamson, R

1998-08-01

The innervation and responses to light of the cephalopod epistellar body were investigated in preparations isolated from the stellate ganglia of the lesser or northern octopus, Eledone cirrhosa. Extracellular generator potentials in response to flashes of light were recorded from these photosensitive vesicles, with the amplitude of the response being found to be dependent upon the intensity of the flash and the level of ambient illumination. Intracellular recordings from photoreceptor cells of the epistellar body showed that they had resting potentials of about -49 +/- 7 mV (mean +/- SD, n = 43) and were depolarized by flashes of white, but not red (>650 nm) light. The evoked depolarization consisted of a transient component, followed by a steady plateau in which the amplitude of the depolarization was well correlated with the log of the stimulus intensity. The evoked depolarizations induced action potentials in the photoreceptor cells, with the frequency of firing being well correlated with the stimulus intensity. The morphologies of individual photoreceptor cells were visualized by intracellular injections of the fluorescent dye Lucifer yellow, and the path of the epistellar nerve across the stellate ganglion, into the pallial nerve, toward the brain was traced using the lipophilic dye Di-I. This pathway was confirmed physiologically by recording light-evoked responses from the cut end of the pallial nerve.

Female reproductive tract of the lesser anteater (Tamandua tetradactyla, myrmecophagidae, Xenarthra). Anatomy and histology.

Science.gov (United States)

Rossi, L F; Luaces, J P; Marcos, H J Aldana; Cetica, P D; Gachen, G; Jimeno, G Pérez; Merani, M S

2011-11-01

The morphological and histological features of the unusual reproductive tract of the female lesser anteater, Tamandua tetradactyla (Myrmecophagidae, Xenarthra), are described for the first time. The present study aimed to establish the main similarities and differences between this species and other xenarthrans. The populations of this species are declining rapidly for a number of reasons and our study is relevant to diverse programs related to its conservation. Studies were carried out on five female genital tracts of adult specimens. Ovaries were ovoid, presenting a medulla completely surrounded by the cortex, differently from that described in other xenarthans. Like in Dasypus but different from all other armadillos studied, single oocyte follicles were observed and a simple the uterus. The uterovaginal canal connects the uterus with the urogenital sinus. The simple columnar epithelium of the uterovaginal canal ends abruptly at a septum which resembles a hymen, where the transitional epithelium of the urogenital sinus appears. This ancestral feature is shared with that of other armadillos, except Tolypeutes matacus, which has a true vagina. Characteristics of the reproductive tract and sperm morphology of other Xenarthra are comparatively discussed. These observations suggest that important reproductive features are shared between the family Myrmecophagidae and the genus Dasypus, a basal group in the phylogeny of Xenarthra. Copyright © 2011 Wiley-Liss, Inc.

Do other cardiovascular risk factors influence the impact of age on the association between blood pressure and mortality?

DEFF Research Database (Denmark)

Vishram, Julie K K; Borglykke, Anders; Andreasen, Anne H

2014-01-01

Hg increase in SBP/DBP by multivariate-adjusted Cox regressions, including SBP and DBP simultaneously. Because of nonlinearity, SBP and DBP were analyzed separately for blood pressure (BP) values above and below a cut-point wherein mortality risk was the lowest. For the total population, significantly...... 82 mmHg [1.03 (1.02-1.05)]. BP values below the cut-points were inversely related to mortality risk. Taking into account the age × BP interaction, there was a gradual shift from DBP (19-26 years) to both DBP and SBP (27-62 years) and to SBP (63-78 years) as risk factors for stroke mortality and all...

Modulation format dependence of digital nonlinearity compensation performance in optical fibre communication systems.

Science.gov (United States)

Xu, Tianhua; Shevchenko, Nikita A; Lavery, Domaniç; Semrau, Daniel; Liga, Gabriele; Alvarado, Alex; Killey, Robert I; Bayvel, Polina

2017-02-20

The relationship between modulation format and the performance of multi-channel digital back-propagation (MC-DBP) in ideal Nyquist-spaced optical communication systems is investigated. It is found that the nonlinear distortions behave independent of modulation format in the case of full-field DBP, in contrast to the cases of electronic dispersion compensation and partial-bandwidth DBP. It is shown that the minimum number of steps per span required for MC-DBP depends on the chosen modulation format. For any given target information rate, there exists a possible trade-off between modulation format and back-propagated bandwidth, which could be used to reduce the computational complexity requirement of MC-DBP.

Longitudinal Trajectories of Perceived Body Weight: Adolescence to Early Adulthood

Science.gov (United States)

Seo, Dong-Chul; Li, Kaigang

2012-01-01

Objective: To examine longitudinal trajectories of perceived weight from adolescence to early adulthood by gender. Methods: We analyzed 9 waves (1997-2005) of data from the National Longitudinal Survey of Youth (N = 8302) using Mplus. Results: Perceived overweight increased over time among girls and did not level off until 23 years of age. Blacks…

Accounting for dropout reason in longitudinal studies with nonignorable dropout.

Science.gov (United States)

Moore, Camille M; MaWhinney, Samantha; Forster, Jeri E; Carlson, Nichole E; Allshouse, Amanda; Wang, Xinshuo; Routy, Jean-Pierre; Conway, Brian; Connick, Elizabeth

2017-08-01

Dropout is a common problem in longitudinal cohort studies and clinical trials, often raising concerns of nonignorable dropout. Selection, frailty, and mixture models have been proposed to account for potentially nonignorable missingness by relating the longitudinal outcome to time of dropout. In addition, many longitudinal studies encounter multiple types of missing data or reasons for dropout, such as loss to follow-up, disease progression, treatment modifications and death. When clinically distinct dropout reasons are present, it may be preferable to control for both dropout reason and time to gain additional clinical insights. This may be especially interesting when the dropout reason and dropout times differ by the primary exposure variable. We extend a semi-parametric varying-coefficient method for nonignorable dropout to accommodate dropout reason. We apply our method to untreated HIV-infected subjects recruited to the Acute Infection and Early Disease Research Program HIV cohort and compare longitudinal CD4 + T cell count in injection drug users to nonusers with two dropout reasons: anti-retroviral treatment initiation and loss to follow-up.

Adolescent psychosocial development: A review of longitudinal models and research.

Science.gov (United States)

Meeus, Wim

2016-12-01

This review used 4 types of longitudinal models (descriptive models, prediction models, developmental sequence models and longitudinal mediation models) to identify regular patterns of psychosocial development in adolescence. Eight patterns of adolescent development were observed across countries: (1) adolescent maturation in multiple developmental domains; (2) heterogeneous continuity of personal relationships; (3) good goes together with good, and bad with bad, across time in adolescence; (4) parents transmit values and behaviors to their adolescent children over time; (5) adolescent psychopathology leads to erosion of personal relationships with parents and peers; (6) adolescent psychopathology prevents adolescent independence from parents; (7) parental interference in personal issues of adolescents has counterproductive effects over time; (8) mood variability and (social and personal) uncertainty are mechanisms that maintain psychopathology in adolescence. Principles of life span developmental psychology are used to discuss adolescent maturation, and a developmental contextual perspective is used to discuss links between the various developmental patterns. Strengths and limitations of the various longitudinal models, and links between longitudinal and experimental research are discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Within-subject template estimation for unbiased longitudinal image analysis.

Science.gov (United States)

Reuter, Martin; Schmansky, Nicholas J; Rosas, H Diana; Fischl, Bruce

2012-07-16

Longitudinal image analysis has become increasingly important in clinical studies of normal aging and neurodegenerative disorders. Furthermore, there is a growing appreciation of the potential utility of longitudinally acquired structural images and reliable image processing to evaluate disease modifying therapies. Challenges have been related to the variability that is inherent in the available cross-sectional processing tools, to the introduction of bias in longitudinal processing and to potential over-regularization. In this paper we introduce a novel longitudinal image processing framework, based on unbiased, robust, within-subject template creation, for automatic surface reconstruction and segmentation of brain MRI of arbitrarily many time points. We demonstrate that it is essential to treat all input images exactly the same as removing only interpolation asymmetries is not sufficient to remove processing bias. We successfully reduce variability and avoid over-regularization by initializing the processing in each time point with common information from the subject template. The presented results show a significant increase in precision and discrimination power while preserving the ability to detect large anatomical deviations; as such they hold great potential in clinical applications, e.g. allowing for smaller sample sizes or shorter trials to establish disease specific biomarkers or to quantify drug effects. Copyright © 2012 Elsevier Inc. All rights reserved.

LONGITUDINAL OSCILLATIONS IN DENSITY STRATIFIED AND EXPANDING SOLAR WAVEGUIDES

Energy Technology Data Exchange (ETDEWEB)

Luna-Cardozo, M. [Instituto de Astronomia y Fisica del Espacio, CONICET-UBA, CC. 67, Suc. 28, 1428 Buenos Aires (Argentina); Verth, G. [School of Computing, Engineering and Information Sciences, Northumbria University, Newcastle Upon Tyne NE1 8ST (United Kingdom); Erdelyi, R., E-mail: mluna@iafe.uba.ar, E-mail: robertus@sheffield.ac.uk, E-mail: gary.verth@northumbria.ac.uk [Solar Physics and Space Plasma Research Centre (SP2RC), University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom)

2012-04-01

Waves and oscillations can provide vital information about the internal structure of waveguides in which they propagate. Here, we analytically investigate the effects of density and magnetic stratification on linear longitudinal magnetohydrodynamic (MHD) waves. The focus of this paper is to study the eigenmodes of these oscillations. It is our specific aim to understand what happens to these MHD waves generated in flux tubes with non-constant (e.g., expanding or magnetic bottle) cross-sectional area and density variations. The governing equation of the longitudinal mode is derived and solved analytically and numerically. In particular, the limit of the thin flux tube approximation is examined. The general solution describing the slow longitudinal MHD waves in an expanding magnetic flux tube with constant density is found. Longitudinal MHD waves in density stratified loops with constant magnetic field are also analyzed. From analytical solutions, the frequency ratio of the first overtone and fundamental mode is investigated in stratified waveguides. For small expansion, a linear dependence between the frequency ratio and the expansion factor is found. From numerical calculations it was found that the frequency ratio strongly depends on the density profile chosen and, in general, the numerical results are in agreement with the analytical results. The relevance of these results for solar magneto-seismology is discussed.

Acute suicidal ideation in middle-aged adults from Brazil. Results from the baseline data of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

Science.gov (United States)

Brunoni, André R; Nunes, Maria A; Lotufo, Paulo A; Benseñor, Isabela M

2015-02-28

Suicidal ideation represents an important burden worldwide. However, little is known about it in low-/middle-income countries. We investigated this issue in a large cross-sectional of Brazilian civil servants (ELSA-Brasil, the Brazilian Health Longitudinal Study, n=15,105). Logistic univariate and multivariate analyses were performed to evaluate the strength of association (odds ratio, OR) between clinical and sociodemographic variables with acute life-weariness (tiredness of life) and suicidal thoughts. The presence of major depressive disorder (MDD), common mental disorders (CMDs), stressful life-events (SLEs) and poor self-perceived physical health was also collected. MDD and CMDs were strongly associated with suicidal ideation in univariate and multivariate analyses. For life-weariness thoughts, a modest, consistent association was found for female gender, being single, non-White ethnicity and poor education. SLEs and poor self-perceived physical health were also associated with suicidal ideation. Espiritism-Kardecism, but not other religions or Atheism/Agnosticism, was associated with lower rates of life-weariness and suicidal thoughts. To conclude, suicidal ideation does not differ in Brazil compared to developed countries, being primarily associated with psychiatric disorders and, to a lesser but significant extent, to social disadvantage, SLEs, poor self-perceived health and being single. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Joint Models for Longitudinal and Time-to-Event Data With Applications in R

CERN Document Server

Rizopoulos, Dimitris

2012-01-01

In longitudinal studies it is often of interest to investigate how a marker that is repeatedly measured in time is associated with a time to an event of interest, e.g., prostate cancer studies where longitudinal PSA level measurements are collected in conjunction with the time-to-recurrence. Joint Models for Longitudinal and Time-to-Event Data: With Applications in R provides a full treatment of random effects joint models for longitudinal and time-to-event outcomes that can be utilized to analyze such data. The content is primarily explanatory, focusing on applications of joint modeling, but

The longitudinal relation between smoking and muscle strength in healthy adults

NARCIS (Netherlands)

Kok, Maarten O; Hoekstra, T.; Twisk, Jos W R

2012-01-01

AIM: To assess longitudinally whether smoking tobacco is related to muscle strength in healthy adults and to assess the influence of lifestyle covariates on this relation. METHODS: Data were obtained from the observational Amsterdam Growth and Health Longitudinal Study, with four repeated

An ultra-sensitive monoclonal antibody-based enzyme-linked immunosobent assay for dibutyl phthalate in human urinary

Energy Technology Data Exchange (ETDEWEB)

Zhou, Lifang [Institute of Pharmacology, Toxicology and Biochemical Pharmaceutics, College of Pharmaceutical Science, Zhejiang University, Hangzhou 310058 (China); Lei, Yajing [Hangzhou EPIE Bio-detection Technology Limited, Hangzhou 310051 (China); Zhang, Dai; Ahmed, Shabbir [Institute of Pharmacology, Toxicology and Biochemical Pharmaceutics, College of Pharmaceutical Science, Zhejiang University, Hangzhou 310058 (China); Chen, Shuqing, E-mail: chenshuqing@zju.edu.cn [Institute of Pharmacology, Toxicology and Biochemical Pharmaceutics, College of Pharmaceutical Science, Zhejiang University, Hangzhou 310058 (China)

2016-01-15

Dibutyl phthalate (DBP) has been extensively used as a plasticizer in many daily products, which is highly toxic to human, notably affecting the reproductive and developmental function. As the previous method is expensive, time-consuming, low sensitivity and just focused on the environment. Present study was aimed to establish an ultra-sensitive and simple method based on good quality monoclonal antibody, applying to evaluate excretion level of DBP in urine samples of Chinese population directly. A monoclonal antibody was generated and characterized after fusion of myeloma cells with spleen cells isolated from BALB/c mouse. The mouse was previously immunized using a specially designed amino derivative of DBP conjugated with bovine serum albumin (BSA) as immunogen. Cross-reactivity values of the monoclonal antibody against DBP, di-isobutyl phthalate (DIBP) were observed 100% and 1.25%, while for dimethyl phthalate (DMP), butyl benzyl phthalate (BBP) and didecyl phthalate (DDP) the values were < 0.06%. The standard curve was constructed at 0–50 ng mL{sup −1} and good linearity (R{sup 2} = 0.994) was achieved. The observed IC{sub 50} (7.34 ng mL{sup −1}) and LOD (0.06 ng mL{sup −1}) values was improved 1000-fold to polyclonal antibody and 5-fold to other monoclonal antibodies. A total 1246 urine samples were analyzed and the detection frequency of DBP was observed 72.87% by ic-ELISA. The 95th percentile and mean concentration of DBP were 12.07 and 3.00 ng mL{sup −1}. Acceptable recovery rates of DBP were 97.8–114.3% and coefficients variation 5.93–11.09%. The concentrations of DBP in females were found significantly higher (p < 0.05) than males. Similarly, the DBP in middle aged and low educated individuals was found higher (p < 0.001) than the others. Considering the adverse health effects, DBP internal exposure in the Chinese population should be reduced. The ic-ELISA method has been proved as a cost effective, specific, and highly sensitive screening

Future Orientation, Impulsivity, and Problem Behaviors: A Longitudinal Moderation Model

Science.gov (United States)

Chen, Pan; Vazsonyi, Alexander T.

2011-01-01

In the current study, based on a sample of 1,873 adolescents between 11.4 and 20.9 years of age from the first 3 waves of the National Longitudinal Study of Adolescent Health, we investigated the longitudinal effects of future orientation on levels of and developmental changes in problem behaviors, while controlling for the effects by impulsivity;…

Specific combination of compound heterozygous mutations in 17β-hydroxysteroid dehydrogenase type 4 (HSD17B4 defines a new subtype of D-bifunctional protein deficiency

Directory of Open Access Journals (Sweden)

McMillan Hugh J

2012-11-01

Full Text Available Abstract Background D-bifunctional protein (DBP deficiency is typically apparent within the first month of life with most infants demonstrating hypotonia, psychomotor delay and seizures. Few children survive beyond two years of age. Among patients with prolonged survival all demonstrate severe gross motor delay, absent language development, and severe hearing and visual impairment. DBP contains three catalytically active domains; an N-terminal dehydrogenase, a central hydratase and a C-terminal sterol carrier protein-2-like domain. Three subtypes of the disease are identified based upon the domain affected; DBP type I results from a combined deficiency of dehydrogenase and hydratase activity; DBP type II from isolated hydratase deficiency and DBP type III from isolated dehydrogenase deficiency. Here we report two brothers (16½ and 14 years old with DBP deficiency characterized by normal early childhood followed by sensorineural hearing loss, progressive cerebellar and sensory ataxia and subclinical retinitis pigmentosa. Methods and results Biochemical analysis revealed normal levels of plasma VLCFA, phytanic acid and pristanic acid, and normal bile acids in urine; based on these results no diagnosis was made. Exome analysis was performed using the Agilent SureSelect 50Mb All Exon Kit and the Illumina HiSeq 2000 next-generation-sequencing (NGS platform. Compound heterozygous mutations were identified by exome sequencing and confirmed by Sanger sequencing within the dehydrogenase domain (c.101C>T; p.Ala34Val and hydratase domain (c.1547T>C; p.Ile516Thr of the 17β-hydroxysteroid dehydrogenase type 4 gene (HSD17B4. These mutations have been previously reported in patients with severe-forms of DBP deficiency, however each mutation was reported in combination with another mutation affecting the same domain. Subsequent studies in fibroblasts revealed normal VLCFA levels, normal C26:0 but reduced pristanic acid beta-oxidation activity. Both DBP

Longitudinal bulk acoustic mass sensor

DEFF Research Database (Denmark)

Hales, Jan Harry; Teva, Jordi; Boisen, Anja

2009-01-01

A polycrystalline silicon longitudinal bulk acoustic cantilever is fabricated and operated in air at 51 MHz. A mass sensitivity of 100 Hz/fg (1 fg=10(-15) g) is obtained from the preliminary experiments where a minute mass is deposited on the device by means of focused ion beam. The total noise...

Longitudinal analysis of mouse SDOCT volumes

Science.gov (United States)

Antony, Bhavna J.; Carass, Aaron; Lang, Andrew; Kim, Byung-Jin; Zack, Donald J.; Prince, Jerry L.

2017-03-01

Spectral-domain optical coherence tomography (SDOCT), in addition to its routine clinical use in the diagnosis of ocular diseases, has begun to fund increasing use in animal studies. Animal models are frequently used to study disease mechanisms as well as to test drug efficacy. In particular, SDOCT provides the ability to study animals longitudinally and non-invasively over long periods of time. However, the lack of anatomical landmarks makes the longitudinal scan acquisition prone to inconsistencies in orientation. Here, we propose a method for the automated registration of mouse SDOCT volumes. The method begins by accurately segmenting the blood vessels and the optic nerve head region in the scans using a pixel classification approach. The segmented vessel maps from follow-up scans were registered using an iterative closest point (ICP) algorithm to the baseline scan to allow for the accurate longitudinal tracking of thickness changes. Eighteen SDOCT volumes from a light damage model study were used to train a random forest utilized in the pixel classification step. The area under the curve (AUC) in a leave-one-out study for the retinal blood vessels and the optic nerve head (ONH) was found to be 0.93 and 0.98, respectively. The complete proposed framework, the retinal vasculature segmentation and the ICP registration, was applied to a secondary set of scans obtained from a light damage model. A qualitative assessment of the registration showed no registration failures.

Combining Geological and Geophysical Data in Volcanic Hazard Estimation for Dominica, Lesser Antilles

Science.gov (United States)

George, O.; Latchman, J. L.; Connor, C.; Malservisi, R.; Connor, L.

2014-12-01

Risk posed by volcanic eruptions are generally quantified in a few ways; in the short term geophysical data such as seismic activity or ground deformation are used to assess the state of volcanic unrest while statistical approaches such as spatial density estimates are used for long term hazard assessment. Spatial density estimates have been used in a number of monogenetic volcanic fields for hazard map generation and utilize the age, location and volumes of previous eruptions to calculate the probability of a new event occurring at a given location within this field. In a previously unpublished study, spatial density estimates of the Lesser Antilles volcanic arc showed the island of Dominica to have the highest likelihood of future vent formation. In this current study, this technique was used in combination with relocated seismic events occurring beneath Dominica within the last ~ 20 years as well as InSAR images of ground deformation to generate a hazard map which not only takes into consideration the past events but also the current state of unrest. Here, geophysical data serve as a weighting factor in the estimates with those centers showing more vigorous activity receiving stronger favorability in the assessment for future activity. In addition to this weighting, the bandwidth utilized in the 2D-radially symmetric kernel density function was optimized using the SAMSE method so as to find the value which best minimizes the error in the estimate. The end results of this study are dynamic volcanic hazards maps which will be readily updatable as changes in volcanic unrest occurs within the system.

Assessment of lesser prairie-chicken lek density relative to landscape characteristics in Texas

Energy Technology Data Exchange (ETDEWEB)

Timmer, Jennifer; Butler, Matthew; Ballard, Warren; Boal, Clint; Whitlaw, Heather

2012-08-31

My 2.5-yr Master's project accomplished the objectives of estimating lesser prairie-chicken (LPC) lek density and abundance in the Texas occupied range and modeling anthropogenic and landscape features associated with lek density by flying helicopter lek surveys for 2 field seasons and employing a line-transect distance sampling method. This project was important for several reasons. Firstly, wildlife managers and biologists have traditionally monitored LPC populations with road-based surveys that may result in biased estimates and do not provide access to privately-owned or remote property. From my aerial surveys and distance sampling, I was able to provide accurate density and abundance estimates, as well as new leks and I detected LPCs outside the occupied range. Secondly, recent research has indicated that energy development has the potential to impact LPCs through avoidance of tall structures, increased mortality from raptors perching on transmission lines, disturbance to nesting hens, and habitat loss/fragmentation. Given the potential wind energy development in the Texas Panhandle, spatial models of current anthropogenic and vegetative features (such as transmission lines, roads, and percent native grassland) influencing lek density were needed. This information provided wildlife managers and wind energy developers in Texas with guidelines for how change in landscape features could impact LPCs. Lastly, LPC populations have faced range-wide declines over the last century and they are currently listed as a candidate species under the Endangered Species Act. I was able to provide timely information on LPC populations in Texas that will be used during the listing process.

VoiLA: A multidisciplinary study of Volatile recycling in the Lesser Antilles Arc

Science.gov (United States)

Collier, J.; Blundy, J. D.; Goes, S. D. B.; Henstock, T.; Harmon, N.; Kendall, J. M.; Macpherson, C.; Rietbrock, A.; Rychert, C.; Van Hunen, J.; Wilkinson, J.; Wilson, M.

2017-12-01

Project VoiLA will address the role of volatiles in controlling geological processes at subduction zones. The study area was chosen as it subducts oceanic lithosphere formed at the slow-spreading Mid Atlantic Ridge. This should result in a different level and pattern of hydration to compare with subduction zones in the Pacific which consume oceanic lithosphere generated at faster spreading rates. In five project components, we will test (1) where volatiles are held within the incoming plate; (2) where they are transported and released below the arc; (3) how the volatile distribution and pathways relate to the construction of the arc; and (4) their relationship to seismic and volcanic hazards and the fractionation of economic metals. Finally, (5) the behaviour of the Lesser Antilles arc will be compared with that of other well-studied systems to improve our wider understanding of the role of water in subduction processes. To address these questions the project will combine seismology; petrology and numerical modelling of wedge dynamics and its consequences on dehydration and melting. So-far island-based fieldwork has included mantle xenolith collection and installation of a temporary seismometer network. In 2016 and 2017 we conducted cruises onboard the RRS James Cook that collected a network of passive-recording and active-recording ocean-bottom seismometer data within the back-arc, fore-arc and incoming plate region. A total of 175 deployments and recoveries were made with the loss of only 6 stations. The presentation will present preliminary results from the project.

Wetland use and feeding by lesser scaup during spring migration across the upper Midwest, USA

Science.gov (United States)

Anteau, M.J.; Afton, A.D.

2009-01-01

Low food availability and forage quality and concomitant decreased lipid reserves of lesser scaup (Aythya affinis; hereafter scaup) during spring migration in the upper Midwest may partially explain reductions in the continental population of scaup. In springs 20042005, we examined wetland use and feeding activity of scaup on 356 randomly-selected wetlands within 6 regions in Iowa, Minnesota, and North Dakota. We examined wetland characteristics that favor high scaup use in 286 of these wetlands. We found that probabilities of wetland use and feeding by scaup increased with turbidity up to 45 and 30 NTU, respectively, but then declined at higher turbidity levels. Wetland use was positively correlated with size of open-water zone and amphipod densities, but was not correlated with chironomid densities. Feeding increased with amphipod density up to 26 m-3 and then declined at higher amphipod densities; scaup seemingly forage most efficiently at amphipod densities above 26 m -3. Wetland use was higher in North Dakota than in southern Minnesota and Iowa. Our results indicate that effective wetland restoration efforts to benefit scaup require maintaining abundant populations of amphipods (generally near 26 m-3 landscape geometric mean) in wetlands with large (> 500 m diameter) open-water zones throughout the upper Midwest, but especially within Iowa and southern Minnesota.

Microbial dynamics during production of lesser mealworms (Alphitobius diaperinus) for human consumption at industrial scale.

Science.gov (United States)

Wynants, E; Crauwels, S; Verreth, C; Gianotten, N; Lievens, B; Claes, J; Van Campenhout, L

2018-04-01

In this study, the microbial dynamics during an industrial production cyle of lesser mealworms (Alphitobius diaperinus), sold for human consumption, were characterised. The microbial numbers as well as the microbial diversity were generally higher for the substrate, existing of remaining feed, faeces and exuviae, than for the larvae. Most of the species-level operational taxonomic units, identified using Illumina MiSeq sequencing, that were present in the feed were also detected in the larvae and vice versa. However, bacterial diversity decreased in the larvae during rearing. These results suggested that the feed is an important determinant of the insect bacterial community, but that some bacterial species show a competitive advantage inside the insect gut and become dominant. A blanching treatment of the larvae after harvest reduced most microbial counts, but the number of aerobic endospores remained at 4.0 log cfu/g. Whereas food pathogens Salmonella spp., Listeria monocytogenes, Bacillus cereus or coagulase-positive staphylococci were not detected in our study, fungal isolates corresponding to the genera Aspergillus and Fusarium were recovered. Therefore, it cannot be excluded that mycotoxins were present. The results of this study contribute to a better understanding of the microbial dynamics and food safety aspects during the production of edible insects. Copyright © 2017 Elsevier Ltd. All rights reserved.

Adaptive digital back-propagation for optical communication systems

NARCIS (Netherlands)

Lin, C.-Y.; Napoli, A.; Spinnler, B.; Sleiffer, V.A.J.M.; Rafique, D.; Kuschnerov, M.; Bohn, M.; Schmauss, B.

2014-01-01

We propose an adaptive digital back-propagation method (A-DBP) to selfdetermine unknown fiber nonlinear coefficient gamma. Performance is experimentally verified with 10224-Gb/s POLMUX-16QAM over 656km. Optimal DBP performance, without knowledge of gamma, is obtained by A-DBP.

Elastography for Thyroid Nodules: The Comparison of Diagnostic Performance on Transverse and Longitudinal Planes

International Nuclear Information System (INIS)

Moon, Hee Jung; Kwak, Jin Young; Kim, Eun Kyung

2012-01-01

To evaluate the diagnostic performance of elastography for thyroid nodules on the transverse and longitudinal planes. Gray scale ultrasonography (US), elastography on trans- verse and longitudinal planes, and fine needle aspiration biopsy for 78 thyroid nodules (malignant: 34 cases, benign: 44 cases) were performed. According to the Asteria criteria of elastography, scores 1 and 2 were classified as probably benign and scores 3 and 4 were classified as suspicious. Strain ratios on transverse and longitudinal planes were measured. Sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and Az value (under the receiver operating characteristics curve) of elastography on transverse and longitudinal planes were calculated and compared. Scores 3 and 4 were more frequently seen in malignant nodules on the longitudinal plane (p value = 0.007), but not significantly seen on the transverse plane (p value = 0.160). Sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and the Az value of elastography on the longitudinal plane were higher than those on the transverse plane, although Az values on the transverse and longtudinal planes were not statistically significant. Diagnostic performance of thyroid elastography, especially sensitivity, were higher on the longitudinal plane than the transverse plane

Geometrical features in longitudinal sputtering hollow cathode discharges for laser applications

NARCIS (Netherlands)

Mihailova, D.B.; Dijk, van J.; Hagelaar, G.J.M.; Karatodorov, S.; Zahariev, P.; Grozeva, M.; Mullen, van der J.J.A.M.

2012-01-01

Longitudinal sputtering hollow cathode discharge (HCD) used as active medium for lasing is studied by means of numerical modelling. Due to the longitudinal non-uniformities of the discharge, the laser operation could be strongly affected. The non-uniformity of the discharge is mainly influenced by

Biosorption of diethyl phthalate ester by living and nonliving Burkholderia cepacia and the role of its cell surface components.

Science.gov (United States)

Luo, Si; Li, Langlang; Chen, Anwei; Zeng, Qingru; Xia, Hao; Gu, Ji-Dong

2017-07-01

In this study, the dibutyl phthalate (DBP) binding properties of a DBP-tolerant bacterium (B. cepacia) were characterized in terms of adsorption kinetics and isotherm. Living and nonliving cells both exhibited rapid removal of DBP, achieving more than 80% of maximum sorption within 30 min of contact and reached the equilibrium after 3 h. The adsorption isotherms were well fitted with the Sips model and the nonliving cells have greater biosorption capacity and affinity for DBP than the living cells. Furthermore, the absence of an active mechanism dependent on metabolism implied that the DBP bioaccumulation by living cells was mainly attribute to passive surface binding. The optimum pH for DBP adsorption by living and nonliving cells were both observed to be 6.0. The biosorptive mechanism of DBP binding by B. cepacia was further confirmed by FTIR analysis and various chemical treatments. FTIR results indicated that the phosphate and CH 2 groups on B. cepacia were the main bounding sites for DBP. Furthermore, 2.28, 2.15, 1.93 and 0.87 g of pretreated cells were obtained from 2.40 g of native cells via extracellular polymeric substances (EPS), superficial layer-capsule, lipids components and cell membrane removal treatments, respectively. Total binding amount of DBP on the native cells, EPS-removed cells, capsule-removed cells, lipids-extracted cells and membrane-removed cells were 26.69, 24.84, 24.93, 16.11 and 10.80 mg, respectively, suggesting that the cell wall lipids, proteins or peptidoglycan might play important roles in the sorption of DBP by B. cepacia. The information could be applied in understanding on the mobility, transport and ultimate fate of PAEs in soil and related environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development of a longitudinal feedback cavity for the beam feedback system

International Nuclear Information System (INIS)

Huang Gang; Chen Huaibi; Huang Wenhui; Tong Dechun; Lin Yuzheng; Zhao Zhentang

2003-01-01

Longitudinal beam feedback system is widely used to damp coupling bunch instability. Kicker is one of the key components of the longitudinal feedback system. A prototype cavity of longitudinal feedback kicker is developed according to the parameter of BEPC II. The usage of nose cone in the kicker design increased the shunt impedance. In order to avoid the extra tapper in the storage ring, the racetrack shape beam pipe is applied in the kicker. The impedance and the bandwidth of the kicker is measured by the coaxial line impedance measurement platform and the result achieved the design goals

Longitudinal in vivo MR imaging of live earthworms.

Science.gov (United States)

Budán, Ferenc; Kovács, Noémi; Engelmann, Péter; Horváth, Ildikó; Veres, Dániel S; Németh, Péter; Szigeti, Krisztián; Máthé, Domokos

2014-11-01

Earthworm (Oligochaeta, Lumbricidae) species are used widely in eco-toxicological tests especially with contaminated soils. These long-term tests are reliable, but a high sample size is needed. Magnetic resonance imaging (MRI) can produce fast, robust, sensitive, and longitudinal morphological results using a small sample size. Performing longitudinal in vivo examinations of earthworms using MRI requires the need for anesthetics to completely avoid earthworm's moving. Our goal was to develop a simple and non-invasive method to anesthetize earthworms for in vivo longitudinal imaging studies. We investigated a number of different anesthesia methods and found that propan-2-ol and its vapor was optimal. We used a commercial sequential nanoScan® PET/MRI system (Mediso Ltd, Hungary, Budapest) to explore feasibility of MR imaging in immobilized earthworms. It was possible to visualize via micro MRI the brain, gastrointestinal tract, seminal vesicles, calciferous gland (Morren gland), and main blood vessels of the circulatory system. Our findings show the possibilities to examine changes in morphology using MRI of certain organs using a reversible, long-term immobilization method. © 2014 Wiley Periodicals, Inc.

[Effects of allelochemical dibutyl phthalate on Gymnodinium breve reactive oxygen species].

Science.gov (United States)

Bie, Cong-Cong; Li, Feng-Min; Li, Yuan-Yuan; Wang, Zhen-Yu

2012-02-01

The purpose of this study was to investigate the mechanism of inhibitory action of dibutyl phthalate (DBP) on red tide algae Gymnodinium breve. Reactive oxygen species (ROS) level, contents of *OH and H2O2, and O2*(-) production rate were investigated, and also for the effects of electron transfer inhibitors on the ROS induction of DBP. The results showed that DBP triggered the synthesis of reactive oxygen species ROS, and with the increase of concentration of DBP, *OH and H2O2 contents in cells accumulated, as for the 3 mg x L(-1) DBP treated algae cultures, OH showed a peak of 33 U x mL(-1) at 48 h, which was about 2. 4 times higher than that in the controlled, and H2O2 contents was about 250 nmol x (10(7) cells)(-1) at 72 h, which was about 5 times higher and also was the highest during the whole culture. Rotenone (an inhibitor of complex I in the mitochondria electron transport chain) decreased the DBP induced ROS production, and dicumarol (an inhibitor of the redox enzyme system in the plasma membrane) stimulated the DBP induced ROS production. Taken all together, the results demonstrated DBP induced over production of reactive oxygen species in G. breve, which is the main inhibitory mechanism, and mitochondria and plasma membrane seem to be the main target site of DBP. These conclusions were of scientific meaning on uncovering the inhibitory mechanism of allelochemical on algae.

Effect of di-butyl phosphate on flash point of PUREX solvent

International Nuclear Information System (INIS)

Srivastav, Ravi Kant; Kumar, Shekhar; Balasubramonian, S.; Kamachi Mudali, U.; Natarajan, R.

2015-01-01

30% Tri-n-butyl phosphate (TBP) in a aliphatic diluent is used as a solvent for PUREX process. This diluent is essentially equivalent to commercial dodecane. The radiolytic and acidic degradation of TBP forms di-butyl phosphate (DBP) which is detrimental to the performance of the solvent during nuclear fuel reprocessing operations. To study the possible effect of DBP on the flashpoint of PUREX solvent, synthetic solutions were made by adding DBP and flashpoints of resultant mixtures were determined with an automatic flashpoint tester as per ASTM procedures. Experimental results indicated virtually no effect of DBP on flash point of PUREX solvent in the concentration ranges of 0-16 g/L DBP. (author)

No-cost gym visits are associated with lower weight and blood pressure among non-Latino black and Latino participants with a diagnosis of hypertension in a multi-site demonstration project

Directory of Open Access Journals (Sweden)

Snehal N. Shah

2018-06-01

Full Text Available Well documented, persistent racial/ethnic health disparities in obesity and hypertension in the US demonstrate the continued need for interventions that focus on people of color who may be at higher risk.We evaluated a demonstration project funded by the CDC's Racial/Ethnic Approaches to Community Health (REACH program at four federally qualified health centers (FQHC and YMCA fitness and wellness centers in Boston. No-cost YMCA memberships were offered from June 2014 to June 2015 to non-Latino black and Latino adults with a diagnosis of hypertension. YMCA visit data were merged with health data for 224 participants (n = 1265 health center visits. We assessed associations between gym visit frequency and weight, body mass index (BMI, systolic blood pressure (SBP, and diastolic blood pressure (DBP using longitudinal time-varying linear fixed-effects models.The total number of gym visits over the entire program duration was 5.5, while the conditional total number of visits (after the first gym visit has been made was 17.3. Having visited the gym at least 10 times before an FQHC exam was, on average, associated with lower weight (1.19 kg, p = 0.01, lower BMI (0.43 kg/m2, p = 0.01 and reductions in SBP (−3.20 mm Hg, p = 0.01 and DBP (−2.06 mm Hg p = 0.01. Having visited the gym an average of 1.4 times per month (study average was associated with reductions in weight, BMI, and DBP.No-cost gym visits were associated with improved weight and blood pressure in hypertensive non-Latino black and Latino adults in this program. Additional evaluation is necessary to assess the sustainability of these effects. Keywords: Hypertension, Obesity, Exercise, Minority health, Health status disparities, Community health centers, Intersectoral collaboration

Moving Targets and Biodiversity Offsets for Endangered Species Habitat: Is Lesser Prairie Chicken Habitat a Stock or Flow?

Directory of Open Access Journals (Sweden)

Todd K. BenDor

2014-03-01

Full Text Available The US Fish and Wildlife Service will make an Endangered Species Act listing decision for the lesser prairie chicken (Tympanuchus pallidicinctus; “LPC” in March 2014. Based on the findings of a single, Uzbek antelope study, conservation plans put forth for the LPC propose to modify and re-position habitat in the landscape through a series of temporary preservation/restoration efforts. We argue that for certain species, including the LPC, dynamic habitat offsets represent a dangerous re-interpretation of habitat provision and recovery programs, which have nearly-universally viewed ecosystem offsets (habitat, wetlands, streams, etc. as “stocks” that accumulate characteristics over time. Any effort to create a program of temporary, moving habitat offsets must consider species’ (1 life history characteristics, (2 behavioral tendencies (e.g., avoidance of impacted areas, nesting/breeding site fidelity, and (3 habitat restoration characteristics, including long temporal lags in reoccupation. If misapplied, species recovery programs using temporary, moving habitat risk further population declines.

Longitudinal tire force estimation based on sliding mode observer

Energy Technology Data Exchange (ETDEWEB)

El Hadri, A.; Cadiou, J.C.; M' Sirdi, N.K. [Versailles Univ., Paris (France). Lab. de Robotique; Beurier, G.; Delanne, Y. [Lab. Central des Ponts, Centre de Nantes (France)

2001-07-01

This paper presents an estimation method for vehicle longitudinal dynamics, particularly the tractive/braking force. The estimation can be used to detect a critical driving situation to improve security. It can be used also in several vehicle control systems. The main characteristics of the vehicle longitudinal dynamics were taken into account in the model used to design an observer and computer simulations. The state variables are the angular wheel velocity, vehicle velocity and the longitudinal tire force. The proposed differential equation of the tractive/braking force is derived using the concept of relaxation length. The observer designed is based on the sliding mode approach using only the angular wheel velocity measurement. The proposed method of estimation is verified through a one-wheel simulation model with a ''Magic formula'' tire model. Simulations results show an excellent reconstruction of the tire force. (orig.)

Correlative roentgenography and morphology of the longitudinal epiphyseal bracket

International Nuclear Information System (INIS)

Ogden, J.A.; Light, T.R.; Conlogue, G.J.; Yale Univ., New Haven, CT

1981-01-01

Detailed examination of a complete chondro-osseous specimen from a patient with duplication of the first ray of the foot revealed the involved metatarsal had a trapezoid-shaped, diaphyseal-metaphyseal osseous unit that was longitudinally bracketed along the lateral side by a functioning physis, epiphysis, and secondary (epiphyseal) ossification center. The physis extended as an arc from the medial proximal side toward and along the lateral side and then back to the medial side distally. The medial side of the diaphysis had a normal periosteum. The longitudinal epiphyseal ossification bracket was a composite of initially separate proximal and distal secondary ossification centers that had progressively extended toward each other and finally coalesced along the laterally placed epiphyseal cartilage. We have termed this deformity the 'longitudinal epiphyseal bracket' (LEB). The macroscopic and microscopic anatomy relevant to initial diagnosis and evaluation of sequential roentgenographic changes will be considered. (orig.)

Improved Longitudinal Blow-up and Shaving in the Booster

CERN Document Server

Hancock, S

2013-01-01

The low-intensity proton beam for p-Pb collisions in the LHC did not come back in the Booster at the beginning of 2013 anything like it had been set up at the end of 2012. In particular there were unexplained intensity fluctuations of ±100%. Although the root cause of the drift in performance was never established, its investigation revealed long-standing issues in the longitudinal plane which, when corrected, allowed single-bunch beams to be delivered with unprecedented reproducibility and control of both intensity and longitudinal emittance. The new approach was adopted for the ion run and subsequently for MDs at higher intensities, where it made possible a robust control of intensity at constant 6D phase space volume. Post-LS1, it may even provide a platform upon which to build a more exotic controlled longitudinal blow-up to generate higher intensity bunches with a flattened line density.

Sample size determination for mediation analysis of longitudinal data.

Science.gov (United States)

Pan, Haitao; Liu, Suyu; Miao, Danmin; Yuan, Ying

2018-03-27

Sample size planning for longitudinal data is crucial when designing mediation studies because sufficient statistical power is not only required in grant applications and peer-reviewed publications, but is essential to reliable research results. However, sample size determination is not straightforward for mediation analysis of longitudinal design. To facilitate planning the sample size for longitudinal mediation studies with a multilevel mediation model, this article provides the sample size required to achieve 80% power by simulations under various sizes of the mediation effect, within-subject correlations and numbers of repeated measures. The sample size calculation is based on three commonly used mediation tests: Sobel's method, distribution of product method and the bootstrap method. Among the three methods of testing the mediation effects, Sobel's method required the largest sample size to achieve 80% power. Bootstrapping and the distribution of the product method performed similarly and were more powerful than Sobel's method, as reflected by the relatively smaller sample sizes. For all three methods, the sample size required to achieve 80% power depended on the value of the ICC (i.e., within-subject correlation). A larger value of ICC typically required a larger sample size to achieve 80% power. Simulation results also illustrated the advantage of the longitudinal study design. The sample size tables for most encountered scenarios in practice have also been published for convenient use. Extensive simulations study showed that the distribution of the product method and bootstrapping method have superior performance to the Sobel's method, but the product method was recommended to use in practice in terms of less computation time load compared to the bootstrapping method. A R package has been developed for the product method of sample size determination in mediation longitudinal study design.

Biodegradation of di-n-Butyl Phthalate by Achromobacter sp. Isolated from Rural Domestic Wastewater

Directory of Open Access Journals (Sweden)

Decai Jin

2015-10-01

Full Text Available A bacterial strain W-1, isolated from rural domestic wastewater, can utilize the environmental hormone di-n-butyl phthalate (DBP as the sole carbon and energy source. The isolated bacterium species was confirmed to belong to the genus Achromobacter based on its 16S rRNA gene sequence. The results of substrate utilization tests showed that the strain W-1 could utilize other common phthalates and phenol. High-performance liquid chromatography analysis revealed that the optimal conditions for DBP degradation were pH 7.0, 35 °C, and an agitation rate of 175 rpm. Under these conditions, 500 mg/L of DBP was completely degraded within 30 h. The effects of heavy metals (50 mg/L Cu2+ and 500 mg/L Pb2+ and surfactants (100 mg/L SDS and 500 mg/L Tween 20 on DBP degradation were investigated. The results demonstrated that Cu2+ and SDS severely inhibited DBP degradation and Pb2+ weakly inhibited DBP degradation, while Tween 20 greatly enhanced DBP degradation. Furthermore, phthalate degradation genes were found to be located on a plasmid present in Achromobacter sp. W-1.

Identification of developmentally toxic drinking water disinfection byproducts and evaluation of data relevant to mode of action

International Nuclear Information System (INIS)

Colman, Joan; Rice, Glenn E.; Wright, J. Michael; Hunter, E. Sidney; Teuschler, Linda K.; Lipscomb, John C.; Hertzberg, Richard C.; Simmons, Jane Ellen; Fransen, Margaret; Osier, Mark; Narotsky, Michael G.

2011-01-01

Reactions between chemicals used to disinfect drinking water and compounds present in source waters produce chemical mixtures containing hundreds of disinfection byproducts (DBPs). Although the results have been somewhat inconsistent, some epidemiological studies suggest associations may exist between DBP exposures and adverse developmental outcomes. The potencies of individual DBPs in rodent and rabbit developmental bioassays suggest that no individual DBP can account for the relative risk estimates reported in the positive epidemiologic studies, leading to the hypothesis that these outcomes could result from the toxicity of DBP mixtures. As a first step in a mixtures risk assessment for DBP developmental effects, this paper identifies developmentally toxic DBPs and examines data relevant to the mode of action (MOA) for DBP developmental toxicity. We identified 24 developmentally toxic DBPs and four adverse developmental outcomes associated with human DBP exposures: spontaneous abortion, cardiovascular defects, neural tube defects, and low birth weight infancy. A plausible MOA, involving hormonal disruption of pregnancy, is delineated for spontaneous abortion, which some epidemiologic studies associate with total trihalomethane and bromodichloromethane exposures. The DBP data for the other three outcomes were inadequate to define key MOA steps.

Adenovirus DNA binding protein inhibits SrCap-activated CBP and CREB-mediated transcription

International Nuclear Information System (INIS)

Xu Xiequn; Tarakanova, Vera; Chrivia, John; Yaciuk, Peter

2003-01-01

The SNF2-related CBP activator protein (SrCap) is a potent activator of transcription mediated by CBP and CREB. We have previously demonstrated that the Adenovirus 2 DNA Binding Protein (DBP) binds to SrCap and inhibits the transcription mediated by the carboxyl-terminal region of SrCap (amino acids 1275-2971). We report here that DBP inhibits the ability of full-length SrCap (1-2971) to activate transcription mediated by Gal-CREB and Gal-CBP. In addition, DBP also inhibits the ability of SrCap to enhance Protein Kinase A (PKA) activated transcription of the enkaphalin promoter. DBP was found to dramatically inhibit transcription of a mammalian two-hybrid system that was dependent on the interaction of SrCap and CBP binding domains. We also found that DBP has no effect on transcription mediated by a transcriptional activator that is not related to SrCap, indicating that our reported transcriptional inhibition is specific for SrCap and not due to nonspecific effects of DBP's DNA binding activity on the CAT reporter plasmid. Taken together, these results suggest a model in which DBP inhibits cellular transcription mediated by the interaction between SrCap and CBP

Heritability of Verbal and Performance Intelligence in a Pediatric Longitudinal Sample

NARCIS (Netherlands)

van Soelen, I.L.C.; Brouwer, R.M.; van Leeuwen, M.; Kahn, R.S.; Hulshoff Pol, H.E.; Boomsma, D.I.

2011-01-01

The longitudinal stability of IQ is well-documented as is its increasing heritability with age. In a longitudinal twin study, we addressed the question to what extent heritability and stability differ for full scale (FSIQ), verbal (VIQ), and performance IQ (PIQ) in childhood (age 9-11 years), and

Racial Differences in Associations of Blood Pressure Components in Young Adulthood With Incident Cardiovascular Disease by Middle Age: Coronary Artery Risk Development in Young Adults (CARDIA) Study.

Science.gov (United States)

Yano, Yuichiro; Reis, Jared P; Tedla, Yacob G; Goff, David C; Jacobs, David R; Sidney, Stephen; Ning, Hongyan; Liu, Kiang; Greenland, Philip; Lloyd-Jones, Donald M

2017-04-01

Data are sparse regarding which blood pressure (BP) components in young adulthood optimally determine cardiovascular disease (CVD) by middle age. To assess which BP components best determine incident CVD events in young adults and determine whether these associations vary by race and age at BP measurement. Using data from the Coronary Artery Risk Development in Young Adults (CARDIA) study, this study assessed the longitudinal race-stratified associations between BP and cardiovascular outcomes. CARDIA is a community-based cohort that recruited black and white individuals (age range, 18-30 years) from March 26, 1985, through June 7, 1986. CARDIA followed up participants for up to 28 years, and 94% of the surviving cohort completed at least 1 telephone interview or examination from August 2009 through August 2014. Blood pressures measubred at baseline (Y0) and 15 years later (Y15). Composite CVD events, including coronary heart disease, stroke, heart failure, and other vascular diseases. A total of 4880 participants participated in the study (mean [SD] age, 24.9 [3.6] years at Y0 and 25.0 [3.6] years at Y15; 2223 male [45.6%] at Y0 and 1800 [44.2%] at Y15; 2657 female [54.4%] at Y0 and 2277 [55.8%] at Y0; 2473 black individuals [50.7%] at Y0 and 1994 [48.9%] at Y15; and 2407 white individuals [49.3%] at Y0 and 2083 [51.1%] at Y15). The mean SBP/DBP was 112/69 mm Hg in blacks and 109/68 mm Hg in whites at Y0 and 117/77 mm Hg in blacks and 110/72 mm Hg in whites at Y15. During a 25-year follow-up from Y0, 210 CVD events occurred (twice as many events in blacks [n = 140] compared with whites), of which 131 (87 in blacks) occurred after Y15. With adjustments for covariates, results from Cox proportional hazards models, including SBP and DBP, jointly suggested that, at Y0, SBP (hazard ratio [HR] per 1-SD increase, 1.32; 95% CI, 1.09-1.61) but not DBP (HR, 1.05; 95% CI, 0.88-1.26) was associated with CVD risk in blacks, whereas DBP (HR, 1.74; 95% CI, 1.21-2.50) but not

Longitudinal multigroup invariance analysis of the satisfaction with food-related life scale in university students.

Science.gov (United States)

Schnettler, Berta; Miranda, Horacio; Miranda-Zapata, Edgardo; Salinas-Oñate, Natalia; Grunert, Klaus G; Lobos, Germán; Sepúlveda, José; Orellana, Ligia; Hueche, Clementina; Bonilla, Héctor

2017-06-01

This study examined longitudinal measurement invariance in the Satisfaction with Food-related Life (SWFL) scale using follow-up data from university students. We examined this measure of the SWFL in different groups of students, separated by various characteristics. Through non-probabilistic longitudinal sampling, 114 university students (65.8% female, mean age: 22.5) completed the SWFL questionnaire three times, over intervals of approximately one year. Confirmatory factor analysis was used to examine longitudinal measurement invariance. Two types of analysis were conducted: first, a longitudinal invariance by time, and second, a multigroup longitudinal invariance by sex, age, socio-economic status and place of residence during the study period. Results showed that the 3-item version of the SWFL exhibited strong longitudinal invariance (equal factor loadings and equal indicator intercepts). Longitudinal multigroup invariance analysis also showed that the 3-item version of the SWFL displays strong invariance by socio-economic status and place of residence during the study period over time. Nevertheless, it was only possible to demonstrate equivalence of the longitudinal factor structure among students of both sexes, and among those older and younger than 22 years. Generally, these findings suggest that the SWFL scale has satisfactory psychometric properties for longitudinal measurement invariance in university students with similar characteristics as the students that participated in this research. It is also possible to suggest that satisfaction with food-related life is associated with sex and age. Copyright © 2017 Elsevier Ltd. All rights reserved.

Salivary Cortisol Mediates Effects of Poverty and Parenting on Executive Functions in Early Childhood

Science.gov (United States)

Blair, Clancy; Granger, Douglas A.; Willoughby, Michael; Mills-Koonce, Roger; Cox, Martha; Greenberg, Mark T.; Kivlighan, Katie T.; Fortunato, Christine K.

2011-01-01

In a predominantly low-income population-based longitudinal sample of 1,292 children followed from birth, higher level of salivary cortisol assessed at ages 7, 15, and 24 months was uniquely associated with lower executive function ability and to a lesser extent IQ at age 3 years. Measures of positive and negative aspects of parenting and…

Endothelial stress induces the release of vitamin D-binding protein, a novel growth factor

International Nuclear Information System (INIS)

Raymond, Marc-Andre; Desormeaux, Anik; Labelle, Andree; Soulez, Mathilde; Soulez, Gilles; Langelier, Yves; Pshezhetsky, Alexey V.; Hebert, Marie-Josee

2005-01-01

Endothelial cells (EC) under stress release paracrine mediators that facilitate accumulation of vascular smooth muscle cells (VSCM) at sites of vascular injury. We found that medium conditioned by serum-starved EC increase proliferation and migration of VSCM in vitro. Fractionation of the conditioned medium followed by mass spectral analysis identified one bioactive component as vitamin D-binding protein (DBP). DBP induced both proliferation and migration of VSMC in vitro in association with increased phosphorylation of ERK 1/2. PD 98059, a biochemical inhibitor of ERK 1/2, abrogated these proliferative and migratory responses in VSMC. DBP is an important carrier for the vitamin-D sterols, 25-hydroxyvitamin-D, and 1α,25-dihydroxyvitamin-D. Both sterols inhibited the activity of DBP on VSMC, suggesting that vitamin D binding sites are important for initiating the activities of DBP on VSMC. Release of DBP at sites of endothelial injury represents a novel pathway favoring accumulation of VSMC at sites of vascular injury

Ureter smooth muscle cell orientation in rat is predominantly longitudinal.

Directory of Open Access Journals (Sweden)

Bart Spronck

Full Text Available In ureter peristalsis, the orientation of the contracting smooth muscle cells is essential, yet current descriptions of orientation and composition of the smooth muscle layer in human as well as in rat ureter are inconsistent. The present study aims to improve quantification of smooth muscle orientation in rat ureters as a basis for mechanistic understanding of peristalsis. A crucial step in our approach is to use two-photon laser scanning microscopy and image analysis providing objective, quantitative data on smooth muscle cell orientation in intact ureters, avoiding the usual sectioning artifacts. In 36 rat ureter segments, originating from a proximal, middle or distal site and from a left or right ureter, we found close to the adventitia a well-defined longitudinal smooth muscle orientation. Towards the lamina propria, the orientation gradually became slightly more disperse, yet the main orientation remained longitudinal. We conclude that smooth muscle cell orientation in rat ureter is predominantly longitudinal, though the orientation gradually becomes more disperse towards the proprial side. These findings do not support identification of separate layers. The observed longitudinal orientation suggests that smooth muscle contraction would rather cause local shortening of the ureter, than cause luminal constriction. However, the net-like connective tissue of the ureter wall may translate local longitudinal shortening into co-local luminal constriction, facilitating peristalsis. Our quantitative, minimally invasive approach is a crucial step towards more mechanistic insight into ureter peristalsis, and may also be used to study smooth muscle cell orientation in other tube-like structures like gut and blood vessels.

Ureter smooth muscle cell orientation in rat is predominantly longitudinal.

Science.gov (United States)

Spronck, Bart; Merken, Jort J; Reesink, Koen D; Kroon, Wilco; Delhaas, Tammo

2014-01-01

In ureter peristalsis, the orientation of the contracting smooth muscle cells is essential, yet current descriptions of orientation and composition of the smooth muscle layer in human as well as in rat ureter are inconsistent. The present study aims to improve quantification of smooth muscle orientation in rat ureters as a basis for mechanistic understanding of peristalsis. A crucial step in our approach is to use two-photon laser scanning microscopy and image analysis providing objective, quantitative data on smooth muscle cell orientation in intact ureters, avoiding the usual sectioning artifacts. In 36 rat ureter segments, originating from a proximal, middle or distal site and from a left or right ureter, we found close to the adventitia a well-defined longitudinal smooth muscle orientation. Towards the lamina propria, the orientation gradually became slightly more disperse, yet the main orientation remained longitudinal. We conclude that smooth muscle cell orientation in rat ureter is predominantly longitudinal, though the orientation gradually becomes more disperse towards the proprial side. These findings do not support identification of separate layers. The observed longitudinal orientation suggests that smooth muscle contraction would rather cause local shortening of the ureter, than cause luminal constriction. However, the net-like connective tissue of the ureter wall may translate local longitudinal shortening into co-local luminal constriction, facilitating peristalsis. Our quantitative, minimally invasive approach is a crucial step towards more mechanistic insight into ureter peristalsis, and may also be used to study smooth muscle cell orientation in other tube-like structures like gut and blood vessels.

Endoscopic submucosal dissection for early gastric cancer on the lesser curvature in upper third of the stomach is a risk factor for postoperative delayed gastric emptying.

Science.gov (United States)

Yoshizaki, Tetsuya; Obata, Daisuke; Aoki, Yasuhiro; Okamoto, Norihiro; Hashimura, Hiroki; Kano, Chise; Matsushita, Megumi; Kanamori, Atsushi; Matsumoto, Kei; Tsujimae, Masahiro; Momose, Kenji; Eguchi, Takaaki; Okuyama, Shunsuke; Yamashita, Hiroshi; Fujita, Mikio; Okada, Akihiko

2018-02-07

Advances in Endoscopic submucosal dissection (ESD) technology have established ESD for early gastric cancer as a safe and stable technique. However, ESD may induce delayed gastric emptying and the cause of food residue retention in the stomach after ESD is not clear. This study aimed to clarify risk factors for delayed gastric emptying with food retention after gastric ESD. We retrospectively examined for food residue in the stomach 1 week after ESD was performed for early gastric carcinoma at Osaka Saiseikai Nakatsu Hospital from February 2008 to November 2016. Food residue was observed in 68 (6.1%) of 1114 patients who underwent gastric ESD. The percentage of lesions located on the lesser curvature of the upper third of the stomach was 45.6% (31/68) in the food residue group and 3.5% (37/1046) in the non-food residue group, which was significantly different (P gastric ESD. Of the 68 patients, 3 had food residue in the stomach on endoscopic examination for follow-up observation after the ESD ulcer had healed. Delayed gastric emptying with food retention after gastric ESD was associated with lesions located in the lesser curvature of the upper stomach, submucosal invasion of the lesion, age older than 80 years, and post-ESD bleeding, though it was temporary in most cases.

Making meaning in the time of AIDS: longitudinal narratives from the ...

African Journals Online (AJOL)

Second, beyond what can be learned from the journals about individual and collective responses to AIDS, they suggest the value of longitudinal observational field studies as a method for understanding how cultural change occurs. And third, as an example of the potential of longitudinal field studies as a research method ...

An alternative longitudinal polarization scheme for tristan

International Nuclear Information System (INIS)

Chao, A.W.; Yokoya, Kaoru.

1981-07-01

For electron storage rings general conditions are derived to get a high level longitudinal polarization and a possible design of the experimental insertion for TRISTAN e-p collider is presented. (author)

Crecimiento longitudinal posnatal del primer metatarsiano. [Longitudinal postnatal growth of the first metatarsal bone

Directory of Open Access Journals (Sweden)

Julio J. Masquijo

2014-10-01

Full Text Available Introducción: si bien el crecimiento prenatal y posnatal del pie ha sido documentado hace varios años, el crecimiento longitudinal del primer metatarsiano en particular no ha sido estudiado previamente. El objetivo del estudio es determinar el patrón de crecimiento longitudinal posnatal de este hueso y compararlo con el del pie y los huesos largos del miembro inferior. Materiales y Métodos: mediante una búsqueda informatizada, se identificaron pacientes <18 años de edad con radiografías informadas como “normal” por el radiólogo. Se analizó una muestra de 886 pacientes divididos en 18 grupos según la edad (0-11 meses, 1 año, 2 años, etc. y el sexo. El análisis de las imágenes se realizó con un software de imágenes Kodak Carestream PACS. Resultados: el largo promedio en el primer grupo fue de 19,91 mm (3,20; 15,22-25,62. El largo promedio en el último grupo fue de 66,13 mm (5,33; 52,50-77,18. La tasa de crecimiento anual fue de 2,71 mm. La edad promedio al momento del cierre de la fisis fue de 14.85 años (± 1.64 para los varones y 14.77 años (± 3.63 para las niñas. Conclusión: el crecimiento del primer metatarsiano acompaña el crecimiento longitudinal del pie, pero no el de los huesos largos del miembro inferior. Las curvas de crecimiento del primer metatarsiano descritas en este artículo pueden ser aplicadas en patologías que afectan el desarrollo del pie o que requieren cirugía de corrección sobre el primer metatarsiano, o se las puede emplear como estándar de referencia en futuros estudios.

Composite marginal quantile regression analysis for longitudinal adolescent body mass index data.

Science.gov (United States)

Yang, Chi-Chuan; Chen, Yi-Hau; Chang, Hsing-Yi

2017-09-20

Childhood and adolescenthood overweight or obesity, which may be quantified through the body mass index (BMI), is strongly associated with adult obesity and other health problems. Motivated by the child and adolescent behaviors in long-term evolution (CABLE) study, we are interested in individual, family, and school factors associated with marginal quantiles of longitudinal adolescent BMI values. We propose a new method for composite marginal quantile regression analysis for longitudinal outcome data, which performs marginal quantile regressions at multiple quantile levels simultaneously. The proposed method extends the quantile regression coefficient modeling method introduced by Frumento and Bottai (Biometrics 2016; 72:74-84) to longitudinal data accounting suitably for the correlation structure in longitudinal observations. A goodness-of-fit test for the proposed modeling is also developed. Simulation results show that the proposed method can be much more efficient than the analysis without taking correlation into account and the analysis performing separate quantile regressions at different quantile levels. The application to the longitudinal adolescent BMI data from the CABLE study demonstrates the practical utility of our proposal. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Longitudinal tracking studies for a high intensity proton synchrotron

International Nuclear Information System (INIS)

Lessner, E.; Cho, Y.; Harkay, K.; Symon, K.

1995-01-01

Results from longitudinal tracking studies for a high intensity proton synchrotron designed for a 1-MW spallation source are presented. The machine delivers a proton beam of 0.5 mA time-averaged current at a repetition rate of 30 Hz. The accelerator is designed to have radiation levels that allow hands-on-maintenance. However, the high beam intensity causes strong space charge fields whose effects may lead to particle loss and longitudinal instabilities. The space charge fields modify the particle distribution, distort the stable bucket area and reduce the rf linear restoring force. Tracking simulations were conducted to analyze the space charge effects on the dynamics of the injection and acceleration processes and means to circumvent them. The tracking studies led to the establishment of the injected beam parameters and rf voltage program that minimized beam loss and longitudinal instabilities. Similar studies for a 10-GeV synchrotron that uses the 2-GeV synchrotron as its injector are also discussed

Longitudinal intensity effects in the CERN Large Hadron Collider

CERN Document Server

AUTHOR|(CDS)2081238; Rivkin, Leonid

This PhD thesis provides an improved knowledge of the LHC longitudinal impedance model and a better understanding of the longitudinal intensity effects. These effects can limit the LHC performance and lead to a reduction of the integrated luminosity. The LHC longitudinal impedance was measured with beams. Results obtained using traditional techniques are consistent with the expectations based on the impedance model, although the measurement precision was proven insufficient for the low impedance of the LHC. Innovative methods to probe the LHC reactive impedance were successfully used. One of the methods is based on exciting the beam with a sinusoidal rf phase modulation to estimate the synchrotron frequency shift from potential-well distortion. In the second method, the impedance is estimated from the loss of Landau damping threshold, which is also found to be in good agreement with analytical estimations. Beam-based impedance measurements agree well with estimations using the LHC impedance model. Macropartic...

Stability of longitudinal bunch length feedback for heavy-ion synchrotrons

Directory of Open Access Journals (Sweden)

D. Lens

2013-03-01

Full Text Available In heavy-ion synchrotrons such as the SIS18 at Helmholtzzentrum für Schwerionenforschung, Helmholtz Centre for Heavy Ion Research (GSI, coherent oscillations of the particle bunches are damped by rf feedback systems to increase the stability and to improve the beam quality. In the longitudinal direction, important modes are the coherent longitudinal dipole and quadrupole oscillation. In this paper we present a new and rigorous approach to analyze the longitudinal feedback to damp these modes. The results are applied to the rf feedback loop at GSI that damps the quadrupole mode. The stability analysis is compared with simulations and is in good agreement with results of a beam experiment. Finally, we summarize practical implications for the operation of the feedback system regarding performance and stability.