DNA residence time is a regulatory factor of transcription repression

Science.gov (United States)

Clauß, Karen; Popp, Achim P.; Schulze, Lena; Hettich, Johannes; Reisser, Matthias; Escoter Torres, Laura; Uhlenhaut, N. Henriette

2017-01-01

Abstract Transcription comprises a highly regulated sequence of intrinsically stochastic processes, resulting in bursts of transcription intermitted by quiescence. In transcription activation or repression, a transcription factor binds dynamically to DNA, with a residence time unique to each factor. Whether the DNA residence time is important in the transcription process is unclear. Here, we designed a series of transcription repressors differing in their DNA residence time by utilizing the modular DNA binding domain of transcription activator-like effectors (TALEs) and varying the number of nucleotide-recognizing repeat domains. We characterized the DNA residence times of our repressors in living cells using single molecule tracking. The residence times depended non-linearly on the number of repeat domains and differed by more than a factor of six. The factors provoked a residence time-dependent decrease in transcript level of the glucocorticoid receptor-activated gene SGK1. Down regulation of transcription was due to a lower burst frequency in the presence of long binding repressors and is in accordance with a model of competitive inhibition of endogenous activator binding. Our single molecule experiments reveal transcription factor DNA residence time as a regulatory factor controlling transcription repression and establish TALE-DNA binding domains as tools for the temporal dissection of transcription regulation. PMID:28977492

Numerical simulation of onshore separation processes - residence time optimization

Energy Technology Data Exchange (ETDEWEB)

Fonte, Clarissa Bergman; Oliveira Junior, Joao Americo Aguirre [Engineering Simulation and Scientific Software (ESSS), Florianopolis, SC (Brazil)], E-mails: clarissa@esss.com.br, joao.aguirre@esss.com.br; Dutra, Eduardo Stein Soares [PETROBRAS E e P Engenharia de Producao, Rio de Janeiro, RJ (Brazil). Gerencia de Engenharia de Instalacoes de Superficie e Automacao], E-mail: eduardodutra@petrobras.com.br

2011-04-15

Cylindrical tanks are commonly used in onshore facilities to process and treat oil and water streams. These tanks generate a gravitational separation and, when sedimentation velocity is reached, the residence time inside the tank is crucial to guarantee proper separation. The ideal geometry for a tank maximizes the effective residence time by providing the largest possible fluid path, along which sedimentation of the denser phase occurs. Large volume tanks can be used for this purpose. However, internal devices, which increase the effective residence time and decrease undesirable hydrodynamic effects, are a commonly used alternative, allowing a reduction in tank size. This study focuses on the application of computational fluid dynamics as a tool to analyze four geometries found in gravitational separation tanks to identify that which offers the highest residence time values. (author)

Atmospheric Residence Times of Continental Aerosols.

Science.gov (United States)

Balkanski, Yves Jacques

The global atmospheric distributions of ^{222}Rn and ^{210 }Pb are simulated with a three-dimensional model of atmospheric transport based on the meteorology of the NASA GISS^1>=neral circulation model. The short-lived radioactive gas ^ {222}Rn (half-life = 3.8d) is emitted almost exclusively from land, at a relatively uniform rate; hence it is an excellent tracer of continental influences. Lead -210 is produced by decay of ^{222} Rn and immediately condenses to preexisting aerosol surfaces. It provides an excellent measure of aerosol residence times in the atmosphere because its source is accurately defined by the ^{222} Rn distribution. Results from the three-dimensional model are compared to measurements of ^ {222}Rn and ^{210 }Pb atmospheric concentrations to evaluate model's long-range transport over oceanic regions and to study the deposition mechanisms of atmospheric aerosols. Model results for ^{222} Rn are used to examine the long-range transport of continental air over two selected oceanic regions, the subantartic Indian Ocean and the North Pacific. It is shown that fast transport of air from southern Africa causes substantial continental pollution at southern mid-latitudes, a region usually regarded as pristine. Air over the North Pacific is heavily impacted by continental influences year round, but the altitude at which the transport occurs varies seasonally. Observations of aerosols at island sites, which are commonly used as diagnostics of continental influences, may be misleading because they do not account for influences at high altitude and because aerosols are efficiently scavenged by deposition during transport. The study of ^{210}Pb focuses on defining the residence times of submicron aerosols in the troposphere. Scavenging in wet convective updrafts is found to provide the dominant sink on a global scale. The globally averaged residence time for ^{210 }Pb-containing aerosols in the troposphere is 7 days. The average increase in residence time

Land processes lead to surprising patterns in atmospheric residence time

Science.gov (United States)

van der Ent, R.; Tuinenburg, O.

2017-12-01

Our research using atmospheric moisture tracking methods shows that the global average atmospheric residence time of evaporation is 8-10 days. This residence time appears to be Gamma distributed with a higher probability of shorter than average residence times and a long tail. As a consequence the median of this residence time is around 5 days. In some places in the world the first few hours/days after evaporation there seems to be a little chance for a moisture particle to precipitate again, which is reflected by a Gamma distribution having a shape parameter below 1. In this study we present global maps of this parameter using different datasets (GLDAS and ERA-Interim). The shape parameter is as such also a measure for the land-atmospheric coupling strength along the path of the atmospheric water particle. We also find that different evaporation components: canopy interception, soil evaporation and transpiration appear to have different residence time distributions. We find a daily cycle in the residence time distribution over land, which is not present over the oceans. In this paper we will show which of the evaporation components is mainly responsible for this daily pattern and thus exhibits the largest daily cycle of land-atmosphere coupling strength.

Axial dispersion of gas and solid phases in a gas—solid packed column at trickle flow

NARCIS (Netherlands)

Roes, A.W.M.; van Swaaij, Willibrordus Petrus Maria

1979-01-01

Axial dispersion of gas and solid phases in a gas—solid packed column at trickle flow, a promising new countercurrent operation, was evaluated using residence time distribution (RTD) experiments. The column was packed with dumped Pall rings, the gas phase was air at ambient conditions and the solid

Real time curriculum map for internal medicine residency

Directory of Open Access Journals (Sweden)

Roberts J Mark

2007-11-01

Full Text Available Abstract Background To manage the voluminous formal curriculum content in a limited amount of structured teaching time, we describe the development and evaluation of a curriculum map for academic half days (AHD in a core internal medicine residency program. Methods We created a 3-year cyclical curriculum map (an educational tool combining the content, methodology and timetabling of structured teaching, comprising a matrix of topics under various specialties/themes and corresponding AHD hours. All topics were cross-matched against the ACP-ASIM in-training examination, and all hours were colour coded based on the categories of core competencies. Residents regularly updated the map on a real time basis. Results There were 208 topics covered in 283 AHD hours. All topics represented core competencies with minimal duplication (78% covered once in 3 years. Only 42 hours (15% involved non-didactic teaching, which increased after implementation of the map (18–19 hours/year versus baseline 5 hours/year. Most AHD hours (78% focused on medical expert competencies. Resident satisfaction (90% response was high throughout (range 3.64 ± 0.21, 3.84 ± 0.14 out of 4, which improved after 1 year but returned to baseline after 2 years. Conclusion We developed and implemented an internal medicine curriculum map based on real time resident input, with minimal topic duplication and high resident satisfaction. The map provided an opportunity to balance didactic versus non-didactic teaching, and teaching on medical versus non medical expert topics.

Inter-generational co-residence and women's work and leisure time in Egypt

Directory of Open Access Journals (Sweden)

Nadia Diamond-Smith

2015-10-01

Full Text Available Background: Labor force participation among women in Egypt remains low, and due to falling fertility and increases life expectancy, women in Egypt in the future may spend more time co-residing with aging in-laws. Past literature has suggested that co-residence in some settings allows women to enter the labor force more, as mother-in-laws help care for their grandchildren, or inhibits labor force participation when mother-in-laws reinforce traditional values. There is little research on co-residence and labor supply, or leisure time, in Egypt. Objective: This paper examines the role of intergenerational co-residence in women's work, work time, and leisure time using data on time allocation in Egypt. Methods: Data were collected from 548 women with a living mother-in-law: 291 co-residing their mother-in-law and 257 not. Survey data included work status, a 24-hour time diary, and a health assessment of the mother-in-law. Multivariate regression models predicted work, work time, and leisure time use using standard models. Results: Co-residing with a disabled mother-in-law was associated with decreased odds of women working and fewer minutes spent working a day. Leisure time was not associated with the co-residence and disability status of a mother-in-law. Factors related to couples' relationships and the woman's views on gender norms were also associated with women working. Conclusions: Co-residence appears to be associated with women's work, depending on the disability status of the co-residing mother-in-law. If increased life expectancy is associated with more time spent in a disabled state for mothers-in-law, this could put downward pressure on women's work in this setting.

Mean Residence Time and Emergency Drinking Water Supply.

Science.gov (United States)

Kralik, Martin; Humer, Franko

2013-04-01

Immediately after securing an endangered population, the first priority of aid workers following a disaster is the distribution of drinking water. Such emergency situations are reported from many parts of the world following regional chemical or nuclear pollution accidents, floods, droughts, rain-induced landslides, tsunami, and other extreme events. It is often difficult to organise a replacement water supply when regular water systems with short residence times are polluted, infiltrated or even flooded by natural or man-made disasters. They are either unusable or their restoration may take months or even years. Groundwater resources, proven safe and protected by the geological environment, with long residence times and the necessary infrastructure for their exploitation, would provide populations with timeous replacement of vulnerable water supply systems and make rescue activities more rapid and effective. Such resources have to be identified and investigated, as a substitute for affected drinking water supplies thereby eliminating or reducing the impact of their failure following catastrophic events. Even in many areas such water resources with long residence times in years or decades are difficult to find it should be known which water supply facilities in the region are matching these requirements to allow in emergency situation the transport of water in tankers to the affected regions to prevent epidemics, importing large quantities of bottled water. One should know the residence time of the water supply to have sufficient time to plan and install new safe water supply facilities. Development of such policy and strategy for human security - both long term and short term - is therefore needed to decrease the vulnerability of populations threatened by extreme events and water supplies with short residence times. Generally: The longer the residence time of groundwater in the aquifer, the lower its vulnerability. The most common and economic methods to estimate

Prediction of residence time distributions in food processing machinery

DEFF Research Database (Denmark)

Karlson, Torben; Friis, Alan; Szabo, Peter

1996-01-01

The velocity field in a co-rotating disc scraped surface heat exchanger (CDHE) is calculated using a finite element method. The residence time distribution for the CDHE is then obtained by tracing particles introduced in the inlet.......The velocity field in a co-rotating disc scraped surface heat exchanger (CDHE) is calculated using a finite element method. The residence time distribution for the CDHE is then obtained by tracing particles introduced in the inlet....

Determinants and the Moderating Effect of Perceived Policy Effectiveness on Residents' Separation Intention for Rural Household Solid Waste.

Science.gov (United States)

Liao, Chuanhui; Zhao, Dingtao; Zhang, Shuang; Chen, Lanfang

2018-04-11

Currently, villages "besieged with garbage" have become a serious problem in rural areas of China. Separation of rural residential solid waste (RRSW) is one of the main strategies for waste reduction. Although previous studies have analyzed the social and psychological motivations of residents' separation intention for municipal solid waste (MSW), little attention has been paid to the situation in rural areas. This paper investigates key factors influencing rural residents' separation intention, as well as analyzing the moderating effects of perceived policy effectiveness on the relationship between the determinants and the intention, using survey data of 538 rural residents in the province of Sichuan in China. The results show that all the proposed key factors influence the separation intention significantly. Furthermore, the policies were divided into two types and the moderating effects were tested for each type. The results show that the perceived effectiveness of both the inducement policy and the capacity building policy moderated the relationship between attitude and separation intention positively, while the perceived effectiveness of the inducement policy moderated the relationship between subjective norms and intention negatively. The findings provide insightful information for policymakers to design effective RRSW separation policies.

Spinning Disc Technology – Residence Time Distribution and Efficiency in Textile Wastewater Treatment Application

Science.gov (United States)

Iacob Tudose, E. T.; Zaharia, C.

2018-06-01

The spinning disc (SD) technology has received increased attention in the last years due to its enhanced fluid flow features resulting in improved property transfers. The actual study focuses on characterization of the flow within a spinning disc system based on experimental data used to establish the residence time distribution (RTD) and its dependence on the feeding liquid flowrate and the disc rotational speed. To obtain these data, an inert tracer (sodium chloride) was injected as a pulse input in the liquid stream entering the disc and the salt concentration of the liquid leaving the disc was continuously recorded. The obtained data indicate that an increase in the liquid flowrate from 10 L/h to 30 L/h determines a narrower RTD function. Also, at rotational speed of 200 rpm, the residence time distribution is broader than that for 500 rpm and 800 rpm. The RTD data suggest that depending on the needed flow characteristics, one can choose a certain flowrate and rotational speed domain for its application. Also, the SD technology was used to process textile wastewater treated with bentonite (as both coagulation and discoloration agent) in order to investigate whether the quality indicators such as the total suspended solid content, turbidity and discoloration, can be improved. The experimental results are promising since the discoloration and the removals of suspended solids attained values of over 40%, and respectively, 50 %, depending on the effluent flowrate (10 l/h and 30 L/h), and the disc rotational speed (200 rpm, 550 rpm and 850 rpm) without any other addition of chemicals, or initiation of other simultaneous treatment processes (e.g., advanced oxidative, or reductive, or biochemical processes). This recommends spinning disc technology as a suitable and promising tool to improve different wastewater characteristics.

Financial and Time Burdens for Medical Students Interviewing for Residency.

Science.gov (United States)

Callaway, Paul; Melhado, Trisha; Walling, Anne; Groskurth, Jordan

2017-02-01

Interviewing for residency positions is increasingly stressful for students and challenging for programs. Little information is available about the costs and time invested by students in interviewing or about the key factors in decisions to accept interview offers. Our objective was to assess the time and financial costs of residency interviewing for an entire class at a regional campus and explore factors influencing student decisions to accept interviews. We used a 14-item survey administered electronically immediately following National Resident Matching Program results. The response rate was 75% (49 of 65 students). About half interviewed in primary care specialties. Thirty students (63%) applied to 20 or more programs, and 91% were offered multiple interviews out of state. Seventy percent limited interviews by time and cost. Other important factors included personal "fit," program reputation, and the quality of residents. About 50% of the students spent more than 20 days and $1,000-$5,000 interviewing; 29% reported spending over $5,000. Students used multiple funding sources, predominantly loans and savings. Primary care applicants applied to fewer out-of-state programs, reported fewer interview days and lower expenses, but received more financial support from programs. Students invested considerable time and resources in interviewing, and these factors significantly influenced their decisions about accepting interviews. The other major factors in interview decisions concerned personal comfort with the program, especially the residents. The costs and time reported in this study could be greater than other schools due to the regional campus location or lower due to the high proportion of students interviewing in primary care.

Effect of Residence Time on Hydrothermal Carbonization of Corn Cob Residual

Directory of Open Access Journals (Sweden)

Lei Zhang

2015-05-01

Full Text Available Hydrothermal carbonization is a promising technique for conversion of industrial waste into valuable products. Producing hydrochar from corn cob residual (CCR in a cost-effective way is key, from an economic standpoint. For this purpose, the effect of residence time in the range of 0.5 to 6 h was studied under the optimal temperature of 250 °C. Results showed that the higher heating value (HHV of hydrochar increased approximately 40% in comparison to that of the raw material; however, prolonging the residence time beyond 0.5 h had a negligible effect on the HHV increase. Chemical compositions and H/C and O/C ratios of hydrochars revealed a minimal effect of longer residence time. Furthermore, thermogravimetric and derivative thermogravimetric analysis (TG/DTG, Fourier transform infrared spectroscopy (FTIR, and X-ray diffraction (XRD analysis of hydrochars also verified that the pyrolysis behavior and chemical structure of hydrochars with various residence times were similar.

Effect of protected research time on ABSITE scores during general surgery residency.

Science.gov (United States)

Orkin, Bruce A; Poirier, Jennifer; Kowal-Vern, Areta; Chan, Edie; Ohara, Karen; Mendoza, Brian

2018-02-01

Objective - To determine whether residents with one or more years of dedicated research time (Research Residents, RR) improved their ABSITE scores compared to those without (Non-Research Residents, N-RR). A retrospective review of general surgery residents' ABSITE scores from 1995 to 2016 was performed. RR were compared to N-RR. Additional analysis of At Risk (AR) v Not At Risk residents (NAR) (35th percentile as PGY1-2) was also performed. Cohort - 147 residents (34 RR and 113 N-RR). There were no differences in initial ABSITE scores (p = 0.47). By definition, the AR group had lower scores than NAR. Overall, post-research RR v PGY-4 N-RR scores did not differ (p = 0.84). Only the AR residents improved their scores (p = 0.0009 v NAR p = 0.42), regardless of research group (p = 0.70). Protected research time did not improve residents' ABSITE scores, regardless of initial scores. At Risk residents improved regardless of research group status. Copyright © 2017 Elsevier Inc. All rights reserved.

Relationships between removal processes and residence times for atmospheric pollutants

International Nuclear Information System (INIS)

Slinn, W.G.N.

1978-01-01

This report is concerned with improving estimates for the residence times of atmospheric trace constituents in various atmospheric reservoirs. Residence times are defined only for steady-state conditions; i.e., when the net growth rate vanishes. The most useful case of vanishing net growth rate is when the total growth rate is equal to the decay rate. It is demonstrated that the most important advance towards improving estimates of pollutant residence times is through proper choices of reservoirs. Chosen reservoirs should possess the following features: steady-state conditions, uniform mixing ratio throughout or throughout specified subreservoirs, and subreservoirs chosen in which removal rates can be treated as approximate constants. An example of a poorly mixed reservoir, the stratosphere, is discussed. In another example, it is suggested that commonly used reservoirs for atmospheric CO 2 have been chosen poorly and that a substantial portion of the anthropogenic CO 2 released during the past 50 years may still be mixing into the stratosphere. In another example, it is suggested that determination of the dry deposition velocity for accumulation-mode aerosol particles may not be so important as previously thought. To improve estimates for the atmospheric residence times of these particles, it is important to increase knowledge of what is called the ascension velocity

Seasonal change of residence time in spring water and groundwater at a mountainous headwater catchment

Science.gov (United States)

Nagano, Kosuke; Tsujimura, Maki; Onda, Yuichi; Iwagami, Sho; Sakakibara, Koichi; Sato, Yutaro

2017-04-01

Determination of water age in headwater is important to consider water pathway, source and storage in the catchment. Previous studies showed that groundwater residence time changes seasonally. These studies reported that mean residence time of water in dry season tends to be longer than that in rainy season, and it becomes shorter as precipitation and discharge amount increases. However, there are few studies to clarify factors causing seasonal change in mean residence time in spring water and groundwater based on observed data. Therefore, this study aims to reveal the relationship between mean residence time and groundwater flow system using SFconcentration in spring and 10 minutes interval hydrological data such as discharge volume, groundwater level and precipitation amount in a headwater catchment in Fukushima, Japan. The SF6 concentration data in spring water observed from April 2015 to November 2016 shows the mean residence time of springs ranged from zero to 14 years. We also observed a clear negative correlation between discharge rate and residence time in the spring. The residence time in shallow groundwater in rainy season was younger as compared with that in low rainfall period. Therefore, the shallow groundwater with young residence time seems to contribute to the spring in rainy season, causing shorter residence time. Additionally, the residence time of groundwater ranged from 3 to 5 years even in low rainfall period. The residence time in high groundwater table level in ridge was older as compared with that in low groundwater table level. These suggest that the contribution of groundwater with older age in the ridge becomes dominant in the low discharge.

Timing of solid food introduction and association with later childhood overweight and obesity: The IDEFICS study.

Science.gov (United States)

Papoutsou, Stalo; Savva, Savvas C; Hunsberger, Monica; Jilani, Hannah; Michels, Nathalie; Ahrens, Wolfgang; Tornaritis, Michael; Veidebaum, Toomas; Molnár, Dénes; Siani, Alfonso; Moreno, Luis A; Hadjigeorgiou, Charis

2018-01-01

This study investigated associations between timing of solid food introduction and childhood obesity and explored maternal characteristics influencing early feeding practices. Cross-sectional data from children 2-9 years (n = 10,808; 50.5% boys) residing in 8 European countries of the IDEFICS study (2007-2008) were included. Late solid food introduction (≥7 months of age) was associated with an increased prevalence of later childhood overweight/obesity among exclusively breastfed children (OR [odds ratio]: 1.38, 95% CI [confidence interval] [1.01, 1.88]). In contrast, early solid food introduction (associated with lower prevalence of overweight/obesity among children that ceased exclusive breastfeeding earlier than 4 months (OR: 0.63, 95% CI [0.47, 0.84]). Children that were introduced to solids right after 6 months exclusive breastfeeding and continued to receive breastmilk (≥12 months) were less likely to become overweight/obese (OR: 0.67, 95% CI [0.51, 0.88]) compared to children that discontinued to receive breastmilk. Analyses were adjusted for age, sex, country, birth weight, parental education level, parental body mass index, tobacco use in pregnancy, gestational weight gain, and gestational diabetes. Underweight mothers, overweight mothers, mothers who reported daily smoking during pregnancy, and low-educated mothers were less likely to follow recommendations on breastfeeding and timely solids introduction. Future studies should examine whether guidelines for solid food introduction timing have to distinguish between exclusively breastfed, formula fed, and too early exclusive breastfeeding-ceased infants. There is also need for more prospective studies; recall bias was an important current limitation. In conclusion, health professionals should emphasize benefits of breastfeeding and appropriate solid food introduction, especially to mothers that are less likely to follow recommendations. © 2017 John Wiley & Sons Ltd.

Working time of neurosurgical residents in Europe--results of a multinational survey.

Science.gov (United States)

Stienen, Martin N; Netuka, David; Demetriades, Andreas K; Ringel, Florian; Gautschi, Oliver P; Gempt, Jens; Kuhlen, Dominique; Schaller, Karl

2016-01-01

The introduction of the European Working Time directive 2003/88/EC has led to a reduction of the working hours with distinct impact on the clinical and surgical activity of neurosurgical residents in training. A survey was performed among European neurosurgical residents between 06/2014 and 03/2015. Multiple logistic regression was used to assess the relationship between responder-specific variables (e.g., age, gender, country, postgraduate year (PGY)) and outcome (e.g., working time). A total of 652 responses were collected, of which n = 532 responses were taken into consideration. In total, 17.5, 22.1, 29.5, 19.5, 5.9, and 5.5 % of European residents indicated to work 80 h/week, respectively. Residents from France and Turkey (OR 4.72, 95 % CI 1.29-17.17, p = 0.019) and Germany (OR 2.06, 95 % CI 1.15-3.67, p = 0.014) were more likely to work >60 h/week than residents from other European countries. In total, 29 % of European residents were satisfied with their current working time, 11.3 % indicated to prefer reduced working time. More than half (55 %) would prefer to work more hours/week if this would improve their clinical education. Residents that rated their operative exposure as insufficient were 2.3 times as likely as others to be willing to work more hours (OR 2.32, 95 % CI 1.47-3.70, p 50 % of his/her working time in the operating room. By contrast, 77.4 % indicate to devote >25 % of their daily working time to administrative work. For every advanced PGY, the likelihood to spend >50 % of the working time in the OR increases by 19 % (OR 1.19, 95 % CI 1.02-1.40, p = 0.024) and the likelihood to spend >50 % of the working time with administrative work decreases by 18 % (OR 0.84, 95 % CI 0.76-0.94, p = 0.002). The results of this survey on >500 European neurosurgical residents clearly prove that less than 40 % conform with the 48-h week as claimed by the WTD2003/88/EC. Still, more than half of them would chose to work

Effect of viscosity on tear drainage and ocular residence time.

Science.gov (United States)

Zhu, Heng; Chauhan, Anuj

2008-08-01

An increase in residence time of dry eye medications including artificial tears will likely enhance therapeutic benefits. The drainage rates and the residence time of eye drops depend on the viscosity of the instilled fluids. However, a quantitative understanding of the dependence of drainage rates and the residence time on viscosity is lacking. The current study aims to develop a mathematical model for the drainage of Newtonian fluids and also for power-law non-Newtonian fluids of different viscosities. This study is an extension of our previous study on the mathematical model of tear drainage. The tear drainage model is modified to describe the drainage of Newtonian fluids with viscosities higher than the tear viscosity and power-law non-Newtonian fluids with rheological parameters obtained from fitting experimental data in literature. The drainage rate through canaliculi was derived from the modified drainage model and was incorporated into a tear mass balance to calculate the transients of total solute quantity in ocular fluids and the bioavailability of instilled drugs. For Newtonian fluids, increasing the viscosity does not affect the drainage rate unless the viscosity exceeds a critical value of about 4.4 cp. The viscosity has a maximum impact on drainage rate around a value of about 100 cp. The trends are similar for shear thinning power law fluids. The transients of total solute quantity, and the residence time agrees at least qualitatively with experimental studies. A mathematical model has been developed for the drainage of Newtonian fluids and power-law fluids through canaliculi. The model can quantitatively explain different experimental observations on the effect of viscosity on the residence of instilled fluids on the ocular surface. The current study is helpful for understanding the mechanism of fluid drainage from the ocular surface and for improving the design of dry eye treatments.

Allocation of Internal Medicine Resident Time in a Swiss Hospital: A Time and Motion Study of Day and Evening Shifts.

Science.gov (United States)

Wenger, Nathalie; Méan, Marie; Castioni, Julien; Marques-Vidal, Pedro; Waeber, Gérard; Garnier, Antoine

2017-04-18

Little current evidence documents how internal medicine residents spend their time at work, particularly with regard to the proportions of time spent in direct patient care versus using computers. To describe how residents allocate their time during day and evening hospital shifts. Time and motion study. Internal medicine residency at a university hospital in Switzerland, May to July 2015. 36 internal medicine residents with an average of 29 months of postgraduate training. Trained observers recorded the residents' activities using a tablet-based application. Twenty-two activities were categorized as directly related to patients, indirectly related to patients, communication, academic, nonmedical tasks, and transition. In addition, the presence of a patient or colleague and use of a computer or telephone during each activity was recorded. Residents were observed for a total of 696.7 hours. Day shifts lasted 11.6 hours (1.6 hours more than scheduled). During these shifts, activities indirectly related to patients accounted for 52.4% of the time, and activities directly related to patients accounted for 28.0%. Residents spent an average of 1.7 hours with patients, 5.2 hours using computers, and 13 minutes doing both. Time spent using a computer was scattered throughout the day, with the heaviest use after 6:00 p.m. The study involved a small sample from 1 institution. At this Swiss teaching hospital, internal medicine residents spent more time at work than scheduled. Activities indirectly related to patients predominated, and about half the workday was spent using a computer. Information Technology Department and Department of Internal Medicine of Lausanne University Hospital.

Effect of Residence Time of Graphitisation on Thermal Conductivity of Molded Graphite

Directory of Open Access Journals (Sweden)

Pedy Artsanti

2010-06-01

Full Text Available The effect of residence time of graphitisation on thermal conductivity of molded graphite has been examined. The examination has been conducted by varying residence time of graphitisation of molded carbon with petroleum coke as raw material and coal tar pitch. Graphitisation has been conducted by heating molded graphite at 2500 °C in argon atmosphere with residention time of 10, 30 and 90 minutes. Graphitisation degree, density, shrinking mass and porosity of molded graphite were examined and so was its thermal conductivity. The result showed that the decrease of porosity and the increase of graphitisation degree due to the increasing of residention time of graphitisation will increase the thermal conductivity of graphite. Molded graphite graphitisized with residence time for 90 minutes residention time gave thermal conductivity of 2.134 Watt/mK and graphitization degree 0.718.

Particle residence times in waters of the Yangtze and Amazon continental shelves

International Nuclear Information System (INIS)

McKee, B.A.; Nittrouer, C.A.; DeMaster, D.J.

1986-01-01

Water column and seabed samples were analyzed for naturally occurring Th-234 to determine particle residence times in Yangtze and Amazon continental-shelf waters. On the Yangtze shelf, the water column was vertically well-mixed and suspended-sediment concentrations decreased offshore (from 230 mg/l near the river mouth to 2 mg/l in mid-shelf waters). Particle residence times increased offshore and ranged from 3.2 hours (12 m water depth) to 7.3 days (60 m water depth). Particle residence times ranged from 3 to 30 times shorter than values predicted by settling of discrete (4-8 micron) particles, suggesting that particles were settling in aggregate form. On the Amazon shelf, a two-layer estuarine flow dominated shelf circulation. Suspended-sediment concentrations on the inner shelf (10-12 m water depth) were much greater in bottom waters (range: 100-880 mg/l) than in surface waters (range 5-60 mg/l) as a result of resuspension. Particle residence times ranged from 1.1 days in surface waters to 2.5 days in bottom waters. Particles probably underwent several cycles of resuspension before permanent removal from the water column

Effect of Resident Involvement on Operative Time and Operating Room Staffing Costs.

Science.gov (United States)

Allen, Robert William; Pruitt, Mark; Taaffe, Kevin M

The operating room (OR) is a major driver of hospital costs; therefore, operative time is an expensive resource. The training of surgical residents must include time spent in the OR, but that experience comes with a cost to the surgeon and hospital. The objective of this article is to determine the effect of surgical resident involvement in the OR on operative time and subsequent hospital labor costs. The Kruskal-Wallis statistical test is used to determine whether or not there is a difference in operative times between 2 groups of cases (with residents and without residents). This difference leads to an increased cost in associated hospital labor costs for the group with the longer operative time. Cases were performed at Greenville Memorial Hospital. Greenville Memorial Hospital is part of the larger healthcare system, Greenville Health System, located in Greenville, SC and is a level 1 trauma center with up to 33 staffed ORs. A total of 84,997 cases were performed at the partnering hospital between January 1st, 2011 and July 31st, 2015. Cases were only chosen for analysis if there was only one CPT code associated with the case and there were more than 5 observations for each group being studied. This article presents a comprehensive retrospective analysis of 29,134 cases covering 246 procedures. The analysis shows that 45 procedures took significantly longer with a resident present in the room. The average increase in operative time was 4.8 minutes and the cost per minute of extra operative time was determined to be $9.57 per minute. OR labor costs at the partnering hospital was found to be $2,257,433, or $492,889 per year. Knowing the affect on operative time and OR costs allows managers to make smart decisions when considering alternative educational and training techniques. In addition, knowing the connection between residents in the room and surgical duration could help provide better estimates of surgical time in the future and increase the predictability of

Explaining Direct Care Resource Use of Nursing Home Residents: Findings from Time Studies in Four States

Science.gov (United States)

Arling, Greg; Kane, Robert L; Mueller, Christine; Lewis, Teresa

2007-01-01

Objective To explain variation in direct care resource use (RU) of nursing home residents based on the Resource Utilization Groups III (RUG-III) classification system and other resident- and unit-level explanatory variables. Data Sources/Study Setting Primary data were collected on 5,314 nursing home residents in 156 nursing units in 105 facilities from four states (CO, IN, MN, MS) from 1998 to 2004. Study Design Nurses and other direct care staff recorded resident-specific and other time caring for all residents on sampled nursing units. Care time was linked to resident data from the Minimum Data Set assessment instrument. Major variables were: RUG-III group (34-group), other health and functional conditions, licensed and other professional minutes per day, unlicensed minutes per day, and direct care RU (wage-weighted minutes). Resident- and unit-level relationships were examined through hierarchical linear modeling. Data Collection/Extraction Methods Time study data were recorded with hand-held computers, verified for accuracy by project staff at the data collection sites and then merged into resident and unit-level data sets. Principal Findings Resident care time and RU varied between and within nursing units. RUG-III group was related to RU; variables such as length of stay and unit percentage of high acuity residents also were significantly related. Case-mix indices (CMIs) constructed from study data displayed much less variation across RUG-III groups than CMIs from earlier time studies. Conclusions Results from earlier time studies may not be representative of care patterns of Medicaid and private pay residents. New RUG-III CMIs should be developed to better reflect the relative costs of caring for these residents. PMID:17362220

Residence times in a hypersaline lagoon: Using salinity as a tracer

Science.gov (United States)

Mudge, Stephen M.; Icely, John D.; Newton, Alice

2008-04-01

Generally the waters of the Ria Formosa Lagoon, Portugal have a short residence time, in the order of 0.5 days (Tett, P., Gilpin, L., Svendsen, H., Erlandsson, C.P., Larsson, U., Kratzer, S., Fouilland, E., Janzen, C., Lee, J., Grenz, C., Newton, A., Ferreira, J.G., Fernandes, T., Scory, S., 2003. Eutrophication and some European waters of restricted exchange. Continental Shelf Research 23, 1635-1671). This estimation is based on the measurements of currents and the modelling of water exchange at the outlets to the ocean. However, observations of the temperature and salinity in the inner channels imply that residence time is greater in these regions of the lagoon. To resolve this apparent contradiction, spatial measurements of the temperature and salinity were made with a meter for conductivity, temperature and depth along the principal channels of the western portion of the lagoon, with a sampling frequency of two per second. Evaporation rates of 5.4 mm day -1 were measured in a salt extraction pond adjacent to the lagoon and used to determine the residence time through salinity differences with the incoming seawater. In June 2004, the water flooding in from the ocean had an average salinity of 36.07 which contrasted with a maximum of 37.82 at mid ebb on a spring tide, corresponding to a residence time of >7 days; the mean residence time was 2.4 days. As the tide flooded into the channels, the existing water was advected back into the lagoon. Although there was a small amount of mixing with water from another inlet, the water body from the inner lagoon essentially remained distinct with respect to temperature and salinity characteristics. The residence time of the water was further prolonged at the junction between the main channels, where distinct boundaries were observed between the different water masses. As the water ebbed out, the shallow Western Channel was essentially isolated from the rest of the outer lagoon, and the water from this channel was forced

Steady And Unsteady Lumped-Parameter Models For Determination of Groundwater Residence Time Distribution

International Nuclear Information System (INIS)

Oezyurt, N.N.

2002-01-01

Groundwater's residence time distribution is an important information to identify the transport mechanism in aquifer systems. In the absence or scarcity of geometric, hydraulic and geohydrologic data needed to describe a flow system, lumped parameter models, that handle the flow system as a whole, exist as an alternative to determine the residence time distribution. Lumped parametre models comprise of idealized models of piston and well-mixed flow and their combinations. Aquifer properties such as, dead volume and by-pass flow can also be included in these models. With the aid of these models, conceptual aquifer models can be tested and residence time distribution of groundwater can be determined

Mean Transit Time and Mean Residence Time for Linear Diffusion–Convection–Reaction Transport System

Directory of Open Access Journals (Sweden)

Jacek Waniewski

2007-01-01

Full Text Available Characteristic times for transport processes in biological systems may be evaluated as mean transit times (MTTs (for transit states or mean residence times (MRT (for steady states. It is shown in a general framework of a (linear reaction–diffusion–convection equation that these two times are related. Analytical formulas are also derived to calculate moments of exit time distribution using solutions for a stationary state of the system.

Single molecule diffusion and the solution of the spherically symmetric residence time equation.

Science.gov (United States)

Agmon, Noam

2011-06-16

The residence time of a single dye molecule diffusing within a laser spot is propotional to the total number of photons emitted by it. With this application in mind, we solve the spherically symmetric "residence time equation" (RTE) to obtain the solution for the Laplace transform of the mean residence time (MRT) within a d-dimensional ball, as a function of the initial location of the particle and the observation time. The solutions for initial conditions of potential experimental interest, starting in the center, on the surface or uniformly within the ball, are explicitly presented. Special cases for dimensions 1, 2, and 3 are obtained, which can be Laplace inverted analytically for d = 1 and 3. In addition, the analytic short- and long-time asymptotic behaviors of the MRT are derived and compared with the exact solutions for d = 1, 2, and 3. As a demonstration of the simplification afforded by the RTE, the Appendix obtains the residence time distribution by solving the Feynman-Kac equation, from which the MRT is obtained by differentiation. Single-molecule diffusion experiments could be devised to test the results for the MRT presented in this work. © 2011 American Chemical Society

Investigation of liquid phase axial dispersion in Taylor bubble flow by radiotracer residence time distribution analysis

Directory of Open Access Journals (Sweden)

Jin J.H.

2013-05-01

Full Text Available A gas-liquid Taylor bubble flow occurs in small diameter channels in which gas bubbles are separated by slugs of pure liquid. This type of flow regime is well suited for solid catalyzed gas-liquid reactors in which the reaction efficiency is a strong function of axial dispersion in the regions of pure liquid. This paper presents an experimental study of liquid phase axial dispersion in a Taylor bubble flow developed in a horizontal tube using high speed photography and radiotracer residence time distribution (RTD analysis. A parametric dependence of axial dispersion on average volume fraction of gas phase was also investigated by varying the relative volumetric flow rates of the two phases. 137mBa produced from a 137Cs/137mBa radionuclide generator was used as radiotracer and measurements were made using the NaI(Tl scintillation detectors. Validation of 137mBa in the form of barium chloride as aqueous phase radiotracer was also carried out. Axial Dispersion Model (ADM was used to simulate the hydrodynamics of the system and the results of the experiment are presented. It was observed that the system is characterized by very high values of Peclet Number (Pe∼102 which reveals an approaching plug type flow. The experimental and model estimated values of mean residence times were observed in agreement with each other.

On the joint residence time of N independent two-dimensional Brownian motions

International Nuclear Information System (INIS)

Benichou, O; Coppey, M; Klafter, J; Moreau, M; Oshanin, G

2003-01-01

We study the behaviour of several joint residence times of N independent Brownian particles in a disc of radius R in two dimensions. We consider: (i) the time T N (t) spent by all N particles simultaneously in the disc within the time interval [0, t], (ii) the time T (m) N (t) which at least m out of N particles spend together in the disc within the time interval [0, t], and (iii) the time T-tilde (m) N (t) which exactly m out of N particles spend together in the disc within the time interval [0, t]. We obtain very simple exact expressions for the expectations of these three residence times in the limit t → ∞

Soil Carbon Residence Time in the Arctic - Potential Drivers of Past and Future Change

Science.gov (United States)

Huntzinger, D. N.; Fisher, J.; Schwalm, C. R.; Hayes, D. J.; Stofferahn, E.; Hantson, W.; Schaefer, K. M.; Fang, Y.; Michalak, A. M.; Wei, Y.

2017-12-01

Carbon residence time is one of the most important factors controlling carbon cycling in ecosystems. Residence time depends on carbon allocation and conversion among various carbon pools and the rate of organic matter decomposition; all of which rely on environmental conditions, primarily temperature and soil moisture. As a result, residence time is an emergent property of models and a strong determinant of terrestrial carbon storage capacity. However, residence time is poorly constrained in process-based models due, in part, to the lack of data with which to benchmark global-scale models in order to guide model improvements and, ultimately, reduce uncertainty in model projections. Here we focus on improving the understanding of the drivers to observed and simulated carbon residence time in the Arctic-Boreal region (ABR). Carbon-cycling in the ABR represents one of the largest sources of uncertainty in historical and future projections of land-atmosphere carbon dynamics. This uncertainty is depicted in the large spread of terrestrial biospheric model (TBM) estimates of carbon flux and ecosystem carbon pool size in this region. Recent efforts, such as the Arctic-Boreal Vulnerability Experiment (ABoVE), have increased the availability of spatially explicit in-situ and remotely sensed carbon and ecosystem focused data products in the ABR. Together with simulations from Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP), we use these observations to evaluate the ability of models to capture soil carbon stocks and changes in the ABR. Specifically, we compare simulated versus observed soil carbon residence times in order to evaluate the functional response and sensitivity of modeled soil carbon stocks to changes in key environmental drivers. Understanding how simulated carbon residence time compares with observations and what drives these differences is critical for improving projections of changing carbon dynamics in the ABR and globally.

Levels and trends of PCDD/Fs in human blood and milk of residents in the vicinity of a modern municipal solid waste incinerator near to Lisbon

Energy Technology Data Exchange (ETDEWEB)

Sampaio, C.; M. Fatima Reis; J. Pereira Miguel [Inst. of Preventive Medicine, Univ. of Lisbon (Portugal); Aguiar, P. [National School of Public Health, New Univ. of Lisbon (Portugal)

2004-09-15

Possible health hazard from human exposure to municipal solid waste (MSW) incinerator emissions, which can include chlorinated persistent organic compounds such as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDDs), is of great public concern. The needed rigorous control of these emissions should be reflected by not different time trends in the PCDD/Fs levels of both the populations residing in the vicinity of incinerators and others selected as control, similar in socio-demographic and other factors potentially influencing those levels. To check the possibility of enhanced body burdens due to MSW emissions, well-designed studies have to be performed to determine human exposure to PCDD/Fs over time. Biological (human) monitoring of these chemicals has several advantages over environmental monitoring, since it is able to measure human body burden and accounts for exposure from all sources, environmental pathways and routes of absorption. However, it is practically unable to identify specific sources, routes and pathways, important issues for risk management purposes. Since 1999, a modern municipal solid waste incinerator is operating in the Metropolitan Area of North-Lisbon, Portugal. In order to get a reliable data basis on the body burden of PCDD/Fs in the population residing in the vicinity of the plant, susceptible of identifying time trends and possible regional differences, a biomonitoring program was implemented in the ambit of the VALORSUL Environmental Health Survey, referred elsewhere. The present paper describes results of this biomonitoring program, which includes repeated cross-sectional studies and, as much as possible, regular examinations of blood and breast milk samples, to determine PCDD/F levels.

Children's postdivorce residence arrangements and parental experienced time pressure

NARCIS (Netherlands)

van der Heijden, Franciëlla; Poortman, Anne Rigt; van der Lippe, Tanja

2016-01-01

Although the rise in postdivorce joint physical custody has fueled scholarly interest in its impact on children, consequences for parents remain understudied. Because children's residence arrangements determine time and coordination demands associated with child care, this study investigated the

Unipolar time-differential charge sensing in non-dispersive amorphous solids

International Nuclear Information System (INIS)

Goldan, A. H.; Rowlands, J. A.; Tousignant, O.; Karim, K. S.

2013-01-01

The use of high resistivity amorphous solids as photodetectors, especially amorphous selenium, is currently of great interest because they are readily produced over large area at substantially lower cost compared to grown crystalline solids. However, amorphous solids have been ruled out as viable radiation detection media for high frame-rate applications, such as single-photon-counting imaging, because of low carrier mobilities, transit-time-limited photoresponse, and consequently, poor time resolution. To circumvent the problem of poor charge transport in amorphous solids, we propose unipolar time-differential charge sensing by establishing a strong near-field effect using an electrostatic shield within the material. For the first time, we have fabricated a true Frisch grid inside a solid-state detector by evaporating amorphous selenium over photolithographically prepared multi-well substrates. The fabricated devices are characterized with optical, x-ray, and gamma-ray impulse-like excitations. Results prove the proposed unipolar time-differential property and show that time resolution in non-dispersive amorphous solids can be improved substantially to reach the theoretical limit set by spatial spreading of the collected Gaussian carrier cloud.

A new time-space accounting scheme to predict stream water residence time and hydrograph source components at the watershed scale

Science.gov (United States)

Takahiro Sayama; Jeffrey J. McDonnell

2009-01-01

Hydrograph source components and stream water residence time are fundamental behavioral descriptors of watersheds but, as yet, are poorly represented in most rainfall-runoff models. We present a new time-space accounting scheme (T-SAS) to simulate the pre-event and event water fractions, mean residence time, and spatial source of streamflow at the watershed scale. We...

Study of solid and liquid behavior in large copper flotation cells (130 m2) using radioactive tracers

International Nuclear Information System (INIS)

Diaz, F.; Jimenez, O.; Yianatos, J.; Contreras, F.

2013-01-01

The behavior of the solid and liquid phases, in large flotation cells, was characterized by means of the radioactive tracer technique. The use of radioactive tracers enabled the identification of the Residence Time Distribution, of floatable and non-floatable solid, from continuous (on-line) measuring at the output streams of the flotation cells. For this study, the proper radioactive tracers were selected and applied in order to characterize the different phases; i.e. for liquid phase Br-82 as Ammonium Bromide, for floatable solid recovered in the concentrate Cu-64, and for non-floatable solid in three particle size classes (coarse: >150 μm, intermediate: 45 μm, and fine: <45 μm), Na-24. The experimental results confirmed the strong effect of particle size on the Residence Time Distribution, and mean residence time of solids in larger flotation cells, and consequently in flotation hydrodynamics. From a hydrodynamic point of view, the experimental data confirmed that a single mechanical flotation cells, of large size, can deviate significantly from perfect mixing. The experimental work was developed in a 130 m3 industrial flotation cell of the rougher circuit at El Teniente Division, Codelco-Chile. (authors)

Residence-time framework for modeling multicomponent reactive transport in stream hyporheic zones

Science.gov (United States)

Painter, S. L.; Coon, E. T.; Brooks, S. C.

2017-12-01

Process-based models for transport and transformation of nutrients and contaminants in streams require tractable representations of solute exchange between the stream channel and biogeochemically active hyporheic zones. Residence-time based formulations provide an alternative to detailed three-dimensional simulations and have had good success in representing hyporheic exchange of non-reacting solutes. We extend the residence-time formulation for hyporheic transport to accommodate general multicomponent reactive transport. To that end, the integro-differential form of previous residence time models is replaced by an equivalent formulation based on a one-dimensional advection dispersion equation along the channel coupled at each channel location to a one-dimensional transport model in Lagrangian travel-time form. With the channel discretized for numerical solution, the associated Lagrangian model becomes a subgrid model representing an ensemble of streamlines that are diverted into the hyporheic zone before returning to the channel. In contrast to the previous integro-differential forms of the residence-time based models, the hyporheic flowpaths have semi-explicit spatial representation (parameterized by travel time), thus allowing coupling to general biogeochemical models. The approach has been implemented as a stream-corridor subgrid model in the open-source integrated surface/subsurface modeling software ATS. We use bedform-driven flow coupled to a biogeochemical model with explicit microbial biomass dynamics as an example to show that the subgrid representation is able to represent redox zonation in sediments and resulting effects on metal biogeochemical dynamics in a tractable manner that can be scaled to reach scales.

Molecular Dynamics Simulations and Kinetic Measurements to Estimate and Predict Protein-Ligand Residence Times.

Science.gov (United States)

Mollica, Luca; Theret, Isabelle; Antoine, Mathias; Perron-Sierra, Françoise; Charton, Yves; Fourquez, Jean-Marie; Wierzbicki, Michel; Boutin, Jean A; Ferry, Gilles; Decherchi, Sergio; Bottegoni, Giovanni; Ducrot, Pierre; Cavalli, Andrea

2016-08-11

Ligand-target residence time is emerging as a key drug discovery parameter because it can reliably predict drug efficacy in vivo. Experimental approaches to binding and unbinding kinetics are nowadays available, but we still lack reliable computational tools for predicting kinetics and residence time. Most attempts have been based on brute-force molecular dynamics (MD) simulations, which are CPU-demanding and not yet particularly accurate. We recently reported a new scaled-MD-based protocol, which showed potential for residence time prediction in drug discovery. Here, we further challenged our procedure's predictive ability by applying our methodology to a series of glucokinase activators that could be useful for treating type 2 diabetes mellitus. We combined scaled MD with experimental kinetics measurements and X-ray crystallography, promptly checking the protocol's reliability by directly comparing computational predictions and experimental measures. The good agreement highlights the potential of our scaled-MD-based approach as an innovative method for computationally estimating and predicting drug residence times.

Influence of temperature on patch residence time in parasitoids: physiological and behavioural mechanisms

Science.gov (United States)

Moiroux, Joffrey; Abram, Paul K.; Louâpre, Philippe; Barrette, Maryse; Brodeur, Jacques; Boivin, Guy

2016-04-01

Patch time allocation has received much attention in the context of optimal foraging theory, including the effect of environmental variables. We investigated the direct role of temperature on patch time allocation by parasitoids through physiological and behavioural mechanisms and its indirect role via changes in sex allocation and behavioural defences of the hosts. We compared the influence of foraging temperature on patch residence time between an egg parasitoid, Trichogramma euproctidis, and an aphid parasitoid, Aphidius ervi. The latter attacks hosts that are able to actively defend themselves, and may thus indirectly influence patch time allocation of the parasitoid. Patch residence time decreased with an increase in temperature in both species. The increased activity levels with warming, as evidenced by the increase in walking speed, partially explained these variations, but other mechanisms were involved. In T. euproctidis, the ability to externally discriminate parasitised hosts decreased at low temperature, resulting in a longer patch residence time. Changes in sex allocation with temperature did not explain changes in patch time allocation in this species. For A. ervi, we observed that aphids frequently escaped at intermediate temperature and defended themselves aggressively at high temperature, but displayed few defence mechanisms at low temperature. These defensive behaviours resulted in a decreased patch residence time for the parasitoid and partly explained the fact that A. ervi remained for a shorter time at the intermediate and high temperatures than at the lowest temperature. Our results suggest that global warming may affect host-parasitoid interactions through complex mechanisms including both direct and indirect effects on parasitoid patch time allocation.

Estimation of gastric residence time of the Heidelberg capsule in humans: effect of varying food composition

International Nuclear Information System (INIS)

Mojaverian, P.; Ferguson, R.K.; Vlasses, P.H.; Rocci, M.L. Jr.; Oren, A.; Fix, J.A.; Caldwell, L.J.; Gardner, C.

1985-01-01

In animal and human studies, the gastric emptying of large (greater than 1 mm) indigestible solids is due to the activity of the interdigestive migrating myoelectric complex. The gastric residence time (GRT) of an orally administered, nondigestible, pH-sensitive, radiotelemetric device (Heidelberg capsule) was evaluated in three studies in healthy volunteers. In 6 subjects, the GRT of the Heidelberg capsule was compared with the half-emptying time (t1/2) of diethylenetriaminepentaacetic acid labeled with technetium 99m after a 4-ml/kg liquid fatty meal. The mean (+/-SD) GRT (4.3 +/- 1.4 h) was significantly (p less than 0.001) longer than the mean t1/2 (1.1 +/- 0.3 h); the GRT was prolonged compared with the t1/2 in each subject. In a randomized, crossover trial in 10 subjects, frequent feeding caused a dramatic prolongation in mean GRT of the capsule compared with the fasting state (greater than 14.5 vs. 0.5 h, p less than 0.005). In another crossover study in 6 subjects, the GRT of the capsule was evaluated after an overnight fast, a standard breakfast including solid food, and a liquid meal (i.e., 200 ml of diluted light cream). The mean GRT was 2.6 +/- 0.9 h after the liquid meal vs. 1.2 +/- 0.8 h after fasting (p less than 0.025). The mean GRT after the breakfast was 4.8 +/- 1.5 h, which was significantly greater than that after fasting (p less than 0.001) and after the liquid meal (p less than 0.01). These data suggest that the GRT of the Heidelberg capsule is a marker of the interdigestive migrating myoelectric complex in humans, the interdigestive migrating myoelectric complex can be markedly delayed by frequent feedings with solids, and the interdigestive migrating myoelectric complex is delayed by both liquid and solid meals

Estimation of gastric residence time of the Heidelberg capsule in humans: effect of varying food composition

Energy Technology Data Exchange (ETDEWEB)

Mojaverian, P.; Ferguson, R.K.; Vlasses, P.H.; Rocci, M.L. Jr.; Oren, A.; Fix, J.A.; Caldwell, L.J.; Gardner, C.

1985-08-01

In animal and human studies, the gastric emptying of large (greater than 1 mm) indigestible solids is due to the activity of the interdigestive migrating myoelectric complex. The gastric residence time (GRT) of an orally administered, nondigestible, pH-sensitive, radiotelemetric device (Heidelberg capsule) was evaluated in three studies in healthy volunteers. In 6 subjects, the GRT of the Heidelberg capsule was compared with the half-emptying time (t1/2) of diethylenetriaminepentaacetic acid labeled with technetium 99m after a 4-ml/kg liquid fatty meal. The mean (+/-SD) GRT (4.3 +/- 1.4 h) was significantly (p less than 0.001) longer than the mean t1/2 (1.1 +/- 0.3 h); the GRT was prolonged compared with the t1/2 in each subject. In a randomized, crossover trial in 10 subjects, frequent feeding caused a dramatic prolongation in mean GRT of the capsule compared with the fasting state (greater than 14.5 vs. 0.5 h, p less than 0.005). In another crossover study in 6 subjects, the GRT of the capsule was evaluated after an overnight fast, a standard breakfast including solid food, and a liquid meal (i.e., 200 ml of diluted light cream). The mean GRT was 2.6 +/- 0.9 h after the liquid meal vs. 1.2 +/- 0.8 h after fasting (p less than 0.025). The mean GRT after the breakfast was 4.8 +/- 1.5 h, which was significantly greater than that after fasting (p less than 0.001) and after the liquid meal (p less than 0.01). These data suggest that the GRT of the Heidelberg capsule is a marker of the interdigestive migrating myoelectric complex in humans, the interdigestive migrating myoelectric complex can be markedly delayed by frequent feedings with solids, and the interdigestive migrating myoelectric complex is delayed by both liquid and solid meals.

Residence Time Distributions in a Cold, Confined Swirl Flow

DEFF Research Database (Denmark)

Lans, Robert Pieter Van Der; Glarborg, Peter; Dam-Johansen, Kim

1997-01-01

Residence time distributions (RTD) in a confined, cold swirling flow have been measured with a fast-response probe and helium as a tracer. The test-rig represented a scaled down version of a burner. The effect of variation of flow velocities and swirl angle on the flow pattern in the near...

Atmospheric residence times of continental aerosols

International Nuclear Information System (INIS)

Balkanski, Y.J.

1991-01-01

The global atmospheric distributions of Rn-222 are simulated with a three-dimensional model of atmospheric transport based on the meteorology of the NASA Goddard Institute for Space Studies (GISS) general circulation model. The short-lived radioactive gas Rn-222 (half-life = 3.8d) is emitted almost exclusively from land, at a relatively uniform rate; hence it is an excellent tracer of continental influences. Lead-210 is produced by decay of Rn-222 and immediately condenses to preexisting aerosol surfaces. It provides an excellent measure of aerosol residence times in the atmosphere because its source is accurately defined by the Rn-222 distribution. Results from the three-dimensional model are compared to measurements of Rn-222 and Pb-210 atmospheric concentrations to evaluate model's long-range transport over oceanic regions and to study the deposition mechanisms of atmospheric aerosols. Model results for Rn-222 are used to examine the long-range transport of continental air over two selected oceanic regions, the subantarctic Indian Ocean and the North Pacific. It is shown that the fast transport of air from southern Africa causes substantial continental pollution at southern mid-latitudes, a region usually regarded as pristine. Air over the North Pacific is heavily impacted by continental influences year round, but the altitude at which the transport occurs varies seasonally. Observations of aerosols at island sites, which are commonly used as diagnostics of continental influences, may be misleading because they do not account for influences at high altitude and because aerosols are efficiently scavenged by deposition during transport. The study of Pb-210 focuses on defining the residence times of submicron aerosols in the troposphere. Scavenging in wet convective updrafts is found to provide the dominant sink on a global scale

Satisfaction and gender issues in otolaryngology residency.

Science.gov (United States)

Wynn, Rhoda; Rosenfeld, Richard M; Lucente, Frank E

2005-06-01

To evaluate the otolaryngology residency experience with attention to operative experience, career guidance, and gender. Otolaryngology residents were anonymously surveyed by mail about their residency experience. The 22-item survey was scored on a 5-point ordinal Likert scale. Responses were analyzed with respect to gender and postgraduate year (PGY) level. Complete surveys were returned by 261 otolaryngology residents (24% female). PGY level correlated with confidence that surgical skills were appropriate (P = 0.003), establishment of solid career network (P = 0.003), and confidence that surgical abilities are adequate for practice (P = 0.028). Female residents reported less confidence that surgical skills were appropriate (P = 0.050) and that surgical abilities were adequate for postresidency practice (P = 0.035). Women were encouraged to enter private practice more often (P = 0.012), were less likely to have a solid career network ( P = 0.025), and were less confident about being able to run their own practice (P = 0.036) Significant differences exist for several questions regarding surgical confidence and career issues, even after correction for PGY level.

Classification of Animal Movement Behavior through Residence in Space and Time.

Science.gov (United States)

Torres, Leigh G; Orben, Rachael A; Tolkova, Irina; Thompson, David R

2017-01-01

Identification and classification of behavior states in animal movement data can be complex, temporally biased, time-intensive, scale-dependent, and unstandardized across studies and taxa. Large movement datasets are increasingly common and there is a need for efficient methods of data exploration that adjust to the individual variability of each track. We present the Residence in Space and Time (RST) method to classify behavior patterns in movement data based on the concept that behavior states can be partitioned by the amount of space and time occupied in an area of constant scale. Using normalized values of Residence Time and Residence Distance within a constant search radius, RST is able to differentiate behavior patterns that are time-intensive (e.g., rest), time & distance-intensive (e.g., area restricted search), and transit (short time and distance). We use grey-headed albatross (Thalassarche chrysostoma) GPS tracks to demonstrate RST's ability to classify behavior patterns and adjust to the inherent scale and individuality of each track. Next, we evaluate RST's ability to discriminate between behavior states relative to other classical movement metrics. We then temporally sub-sample albatross track data to illustrate RST's response to less resolved data. Finally, we evaluate RST's performance using datasets from four taxa with diverse ecology, functional scales, ecosystems, and data-types. We conclude that RST is a robust, rapid, and flexible method for detailed exploratory analysis and meta-analyses of behavioral states in animal movement data based on its ability to integrate distance and time measurements into one descriptive metric of behavior groupings. Given the increasing amount of animal movement data collected, it is timely and useful to implement a consistent metric of behavior classification to enable efficient and comparative analyses. Overall, the application of RST to objectively explore and compare behavior patterns in movement data can

Prevalence and cost of full-time research fellowships during general surgery residency: a national survey.

Science.gov (United States)

Robertson, Charles M; Klingensmith, Mary E; Coopersmith, Craig M

2009-01-01

To quantify the prevalence, outcomes, and cost of surgical resident research. General surgery is unique among graduate medical education programs because a large percentage of residents interrupt their clinical training to spend 1 to 3 years performing full-time research. No comprehensive data exists on the scope of this practice. Survey sent to all 239 program directors of general surgery residencies participating in the National Resident Matching Program. Response rate was 200 of 239 (84%). A total of 381 of 1052 trainees (36%) interrupt residency to pursue full-time research. The mean research fellowship length is 1.7 years, with 72% of trainees performing basic science research. A significant association was found between fellowship length and postresidency activity, with a 14.7% increase in clinical fellowship training and a 15.2% decrease in private practice positions for each year of full-time research (P < 0.0001). Program directors at 31% of programs reported increased clinical duties for research fellows as a result of Accreditation Council for Graduate Medical Education work hour regulations for clinical residents, whereas a further 10% of programs are currently considering such changes. It costs $41.5 million to pay the 634 trainees who perform research fellowships each year, the majority of which is paid for by departmental funds (40%) and institutional training grants (24%). Interrupting residency to perform a research fellowship is a common and costly practice among general surgery residents. Although performing a research fellowship is associated with clinical fellowship training after residency, it is unclear to what extent this practice leads to the development of surgical investigators after postgraduate training.

Lean principles optimize on-time vascular surgery operating room starts and decrease resident work hours.

Science.gov (United States)

Warner, Courtney J; Walsh, Daniel B; Horvath, Alexander J; Walsh, Teri R; Herrick, Daniel P; Prentiss, Steven J; Powell, Richard J

2013-11-01

Lean process improvement techniques are used in industry to improve efficiency and quality while controlling costs. These techniques are less commonly applied in health care. This study assessed the effectiveness of Lean principles on first case on-time operating room starts and quantified effects on resident work hours. Standard process improvement techniques (DMAIC methodology: define, measure, analyze, improve, control) were used to identify causes of delayed vascular surgery first case starts. Value stream maps and process flow diagrams were created. Process data were analyzed with Pareto and control charts. High-yield changes were identified and simulated in computer and live settings prior to implementation. The primary outcome measure was the proportion of on-time first case starts; secondary outcomes included hospital costs, resident rounding time, and work hours. Data were compared with existing benchmarks. Prior to implementation, 39% of first cases started on time. Process mapping identified late resident arrival in preoperative holding as a cause of delayed first case starts. Resident rounding process inefficiencies were identified and changed through the use of checklists, standardization, and elimination of nonvalue-added activity. Following implementation of process improvements, first case on-time starts improved to 71% at 6 weeks (P = .002). Improvement was sustained with an 86% on-time rate at 1 year (P < .001). Resident rounding time was reduced by 33% (from 70 to 47 minutes). At 9 weeks following implementation, these changes generated an opportunity cost potential of $12,582. Use of Lean principles allowed rapid identification and implementation of perioperative process changes that improved efficiency and resulted in significant cost savings. This improvement was sustained at 1 year. Downstream effects included improved resident efficiency with decreased work hours. Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All

Children's Perspectives on Everyday Experiences of Shared Residence: Time, Emotions and Agency Dilemmas

Science.gov (United States)

Haugen, Gry Mette D.

2010-01-01

Shared residence is often presented as an arrangement that is in the best interests of the child following the divorce of its parents. Based on in-depth interviews with Norwegian children who have experienced shared residence, this article seeks to explore some dilemmas concerning time, agency and the children's emotions. Three characteristics of…

Residence time and physical processes in lakes

Directory of Open Access Journals (Sweden)

Nicoletta SALA

2003-09-01

Full Text Available The residence time of a lake is highly dependent on internal physical processes in the water mass conditioning its hydrodynamics; early attempts to evaluate this physical parameter emphasize the complexity of the problem, which depends on very different natural phenomena with widespread synergies. The aim of this study is to analyse the agents involved in these processes and arrive at a more realistic definition of water residence time which takes account of these agents, and how they influence internal hydrodynamics. With particular reference to temperate lakes, the following characteristics are analysed: 1 the set of the lake's caloric components which, along with summer heating, determine the stabilizing effect of the surface layers, and the consequent thermal stratification, as well as the winter destabilizing effect; 2 the wind force, which transfers part of its momentum to the water mass, generating a complex of movements (turbulence, waves, currents with the production of active kinetic energy; 3 the water flowing into the lake from the tributaries, and flowing out through the outflow, from the standpoint of hydrology and of the kinetic effect generated by the introduction of these water masses into the lake. These factors were studied in the context of the general geographical properties of the lake basin and the watershed (latitude, longitude, morphology, also taking account of the local and regional climatic situation. Also analysed is the impact of ongoing climatic change on the renewal of the lake water, which is currently changing the equilibrium between lake and atmosphere, river and lake, and relationships

Conceptual framework for model-based analysis of residence time distribution in twin-screw granulation

DEFF Research Database (Denmark)

Kumar, Ashish; Vercruysse, Jurgen; Vanhoorne, Valerie

2015-01-01

Twin-screw granulation is a promising continuous alternative for traditional batchwise wet granulation processes. The twin-screw granulator (TSG) screws consist of transport and kneading element modules. Therefore, the granulation to a large extent is governed by the residence time distribution...... within each module where different granulation rate processes dominate over others. Currently, experimental data is used to determine the residence time distributions. In this study, a conceptual model based on classical chemical engineering methods is proposed to better understand and simulate...... the residence time distribution in a TSG. The experimental data were compared with the proposed most suitable conceptual model to estimate the parameters of the model and to analyse and predict the effects of changes in number of kneading discs and their stagger angle, screw speed and powder feed rate...

Impact of the European Working Time Directive (EWTD) on the operative experience of surgery residents.

Science.gov (United States)

Hopmans, Cornelis J; den Hoed, Pieter T; van der Laan, Lijckle; van der Harst, Erwin; van der Elst, Maarten; Mannaerts, Guido H H; Dawson, Imro; Timman, Reinier; Wijnhoven, Bas P L; IJzermans, Jan N M

2015-04-01

In Europe and the United States, work hour restrictions are considered to be particularly burdensome for residents in surgery specialties. The aim of this study was to examine whether reduction of the work week to 48 hours resulting from the implementation of the European Working Time Directive has affected the operative experience of surgery residents. This study was conducted in a general surgery training region in the Netherlands, consisting of 1 university hospital and 6 district training hospitals. Operating records summarizing the surgical procedures performed as "primary surgeon" in the operating theater for different grades of surgeons were retrospectively analyzed for the period 2005-2012 by the use of linear regression models. Operative procedures performed by residents were considered the main outcome measure. In total, 235,357 operative procedures were performed, including 47,458 (20.2%) in the university hospital and 187,899 (79.8%) in the district training hospitals (n = 5). For residents in the university hospital, the mean number of operative procedures performed per 1.0 full-time equivalent increased from 128 operations in 2005 to 204 operations in 2012 (P = .001), whereas for residents in district training hospitals, no substantial differences were found over time. The mean (±SD) operative caseload of 64 residents who completed the 6-year training program between 2005 and 2012 was 1,391 ± 226 (range, 768-1856). A comparison of the operative caseload according to year of board-certification showed no difference. Implementation of the European Working Time Directive has not affected adversely the number of surgical procedures performed by residents within a general surgical training region in the Netherlands. Copyright © 2015 Elsevier Inc. All rights reserved.

Prevalence and Cost of Full-Time Research Fellowships During General Surgery Residency – A National Survey

Science.gov (United States)

Robertson, Charles M.; Klingensmith, Mary E.; Coopersmith, Craig M.

2009-01-01

Structured Abstract Objective To quantify the prevalence, outcomes, and cost of surgical resident research. Summary Background Data General surgery is unique among graduate medical education programs because a large percentage of residents interrupt their clinical training to spend 1-3 years performing full-time research. No comprehensive data exists on the scope of this practice. Methods Survey sent to all 239 program directors of general surgery residencies participating in the National Resident Matching Program. Results Response rate was 200/239 (84%). A total of 381 out of 1052 trainees (36%) interrupt residency to pursue full-time research. The mean research fellowship length is 1.7 years, with 72% of trainees performing basic science research. A significant association was found between fellowship length and post-residency activity, with a 14.7% increase in clinical fellowship training and a 15.2% decrease in private practice positions for each year of full-time research (p<0.0001). Program directors at 31% of programs reported increased clinical duties for research fellows as a result of ACGME work hour regulations for clinical residents, while a further 10% of programs are currently considering such changes. It costs $41.5 million to pay the 634 trainees who perform research fellowships each year, the majority of which is paid for by departmental funds (40%) and institutional training grants (24%). Conclusions Interrupting residency to perform a research fellowship is a common and costly practice among general surgery residents. While performing a research fellowship is associated with clinical fellowship training after residency, it is unclear to what extent this practice leads to the development of surgical investigators after post-graduate training. PMID:19106692

Assessing total and volatile solids in municipal solid waste samples.

Science.gov (United States)

Peces, M; Astals, S; Mata-Alvarez, J

2014-01-01

Municipal solid waste is broadly generated in everyday activities and its treatment is a global challenge. Total solids (TS) and volatile solids (VS) are typical control parameters measured in biological treatments. In this study, the TS and VS were determined using the standard methods, as well as introducing some variants: (i) the drying temperature for the TS assays was 105°C, 70°C and 50°C and (ii) the VS were determined using different heating ramps from room tempature to 550°C. TS could be determined at either 105°C or 70°C, but oven residence time was tripled at 70°C, increasing from 48 to 144 h. The VS could be determined by smouldering the sample (where the sample is burnt without a flame), which avoids the release of fumes and odours in the laboratory. However, smouldering can generate undesired pyrolysis products as a consequence of carbonization, which leads to VS being underestimated. Carbonization can be avoided using slow heating ramps to prevent the oxygen limitation. Furthermore, crushing the sample cores decreased the time to reach constant weight and decreased the potential to underestimate VS.

Accessing doctors at times of need-measuring the distance tolerance of rural residents for health-related travel.

Science.gov (United States)

McGrail, Matthew Richard; Humphreys, John Stirling; Ward, Bernadette

2015-05-29

Poor access to doctors at times of need remains a significant impediment to achieving good health for many rural residents. The two-step floating catchment area (2SFCA) method has emerged as a key tool for measuring healthcare access in rural areas. However, the choice of catchment size, a key component of the 2SFCA method, is problematic because little is known about the distance tolerance of rural residents for health-related travel. Our study sought new evidence to test the hypothesis that residents of sparsely settled rural areas are prepared to travel further than residents of closely settled rural areas when accessing primary health care at times of need. A questionnaire survey of residents in five small rural communities of Victoria and New South Wales in Australia was used. The two outcome measures were current travel time to visit their usual doctor and maximum time prepared to travel to visit a doctor, both for non-emergency care. Kaplan-Meier charts were used to compare the association between increased distance and decreased travel propensity for closely-settled and sparsely-settled areas, and ordinal multivariate regression models tested significance after controlling for health-related travel moderating factors and town clustering. A total of 1079 questionnaires were completed with 363 from residents in closely-settled locations and 716 from residents in sparsely-settled areas. Residents of sparsely-settled communities travel, on average, 10 min further than residents of closely-settled communities (26.3 vs 16.9 min, p time prepared to travel (54.1 vs 31.9 min, p time remained significant after controlling for demographic and other constraints to access, such as transport availability or difficulties getting doctor appointments, as well as after controlling for town clustering and current travel times. Improved geographical access remains a key issue underpinning health policies designed to improve the provision of rural primary health care

Tracer concentration curves and residence time analysis in technological flow systems. 2

International Nuclear Information System (INIS)

Pippel, W.

1976-01-01

Tracer concentration curves measured in flow systems by means of radioactive isotopes are treated as a two dimensional random process. Comparing them with the family distribution functions described in part I, it follows that only in case of ergodic behaviour of the system tracer curves can be considered as age distribution functions. The conception of ergodicity in residence time systems has been explained with the aid of a time function measurable by a special method of radioactive tracer technique and by the mean value of the residence time obtainable from this function. Furthermore, technological consequences in evaluating tracer concentration curves of real flow systems are discussed with respect to supposed ergodic or nonergodic behaviour. These considerations are of special importance for flow systems with temporary fluctuations in structure. (author)

Development of Electronic Medical Record-Based "Rounds Report" Results in Improved Resident Efficiency, More Time for Direct Patient Care and Education, and Less Resident Duty Hour Violations.

Science.gov (United States)

Ham, Phillip B; Anderton, Toby; Gallaher, Ryan; Hyrman, Mike; Simmerman, Erika; Ramanathan, Annamalai; Fallaw, David; Holsten, Steven; Howell, Charles Gordon

2016-09-01

Surgeons frequently report frustration and loss of efficiency with electronic medical record (EMR) systems. Together, surgery residents and a programmer at Augusta University created a rounds report (RR) summarizing 24 hours of vitals, intake/output, labs, and other values for each inpatient that were previously transcribed by hand. The objective of this study was to evaluate the RR's effect on surgery residents. Surgery residents were queried to assess the RR's impact. Outcome measures were time spent preparing for rounds, direct patient care time, educational activity time, rates of incorrect/incomplete data on rounds, and rate of duty hour violations. Hospital wide, 17,200 RRs were generated in the 1-month study. Twenty-three surgery residents participated. Time spent preparing for rounds decreased per floor patient (15.6 ± 3.0 vs 6.0 ± 1.2, P care unit patient (19.9 ± 2.9 vs 7.5 ± 1.2 P care increased from 45.1 ± 5.6 to 54.0 ± 5.7 per cent (P = 0.0044). Educational activity time increased from 35.2 ± 5.4 to 54.7 ± 7.1 minutes per resident per day (P = 0.0004). Reported duty hour violations decreased 58 per cent (P care at academic medical centers.

Mineralogical Controls over Carbon Storage and Residence Times in Grassland Soils

Science.gov (United States)

Dwivedi, D.; Riley, W. J.; Torn, M. S.; Spycher, N.

2014-12-01

Globally, soil organic matter (SOM) contains approximately three times more carbon than the atmosphere and terrestrial vegetation contain combined. However, it is not well understood why some SOM persists for a long time while other SOM decomposes quickly. For future climate predictions, representing soil organic matter (SOM) dynamics accurately in Earth system models is essential. Soil minerals stabilize organic carbon in soil; however, there are gaps in our understanding of how soil mineralogy controls the quantity and turnover of long-residence-time organic carbon. To investigate the impact of soil mineralogy on SOM dynamics, we used a new model (Biotic and Abiotic Model of SOM—BAMS1 [Riley et al., 2014]) integrated with a three-dimensional, multiphase reactive transport solver (TOUGHREACT). The model represents bacterial and fungal activity, archetypal polymer and monomer carbon substrate groups, aqueous chemistry, gaseous diffusion, aqueous advection and diffusion, and adsorption and desorption processes. BAMS1 can predict bulk SOM and radiocarbon signatures without resorting to an arbitrary depth-dependent decline in SOM turnover rates. Results show a reasonable match between observed and simulated depth-resolved SOM and Δ14C in grassland ecosystems (soils formed on terraces south of Eureka, California, and the Central Chernozem Region of Russia) and were consistent with expectations of depth-resolved profiles of lignin content and fungi:aerobic bacteria ratios. Results also suggest that clay-mineral surface area and soil sorption coefficients constitute dominant controls over organic carbon stocks and residence times, respectively. Bibliography: Riley, W.J., F.M. Maggi, M. Kleber, M.S. Torn, J.Y. Tang, D. Dwivedi, and N. Guerry (2014), Long residence times of rapidly decomposable soil organic matter: application of a multi-phase, multi-component, and vertically resolved model (BAMS1) to soil carbon dynamics, Geoscientific Model Development, vol. 7, 1335

Determination of the resident time distribution (RTD) in copper concentrate drying plants using radioactive tracers

International Nuclear Information System (INIS)

Diaz V, Francisco J.; Duran P, Oscar U.; Hernandez A, Fernando A.

1996-01-01

This paper is a study on the drying process of copper concentrate, on two fluidized bed dryers at Fundicion Caletones, Division El Teniente, Codelco-Chile. The problem was investigated by experimental determination of the resident Time Distribution (RTD) for the material to be dry and by an analysis of the influence of the grain size in the drying process. The stimulus-response technique was used in the experiments, where the stimulation was a pulse of an adequate radioactive tracer injected at the dryer's input. Under these conditions, the response obtained at the dryer's outputs, i.e., the concentration variation curve as a function of time, represents directly the RTD of the system between the injection and measuring points. The tracer used was the same material to be dried, and it was irradiated with neutrons in the nuclear reactor at La Reina Nuclear Centre, thus producing a solid gamma radiation emitter tracer of identical behaviour as the material under study. The approximate activity of each sample was equivalent to 8 mCi of Cu-64 at the time of the injection and the measurement of the tracer was made on-line using NaI(Tl) gamma radiation detectors. The results obtained showed average times less than the estimated and would indicate a fast drying using minimum volume in the dryer. The drying of the fine particles was three times faster than the coarse ones. (author)

Dedicated Shift Wrap-up Time Does Not Improve Resident Sign-out Volume or Efficiency.

Science.gov (United States)

Jeanmonod, Rebecca K; Brook, Christopher; Winther, Mark; Pathak, Soma; Boyd, Molly

2010-02-01

Sign-out (SO) is a challenge to the emergency physician. Some training programs have instituted overlapping 9-hour shifts. The residents see patients for eight hours, and have one hour of wrap-up time. This hour helps them complete patient care, leaving fewer patients to sign-out. We examined whether this strategy impacts SO burden. This is a retrospective review of patients evaluated by emergency medicine (EM) residents working 9-hour (eight hours of patient care, one hour wrap-up time) and 12-hour shifts (12 hours patient care, no reserved time for wrap-up). Data were collected by reviewing the clinical tracker. A patient was assigned to the resident who initiated care and dictated the chart. SO was defined as any patient in the ED without disposition at change of shift. Patient turn-around-time (TAT) was also recorded. One-hundred sixty-one postgraduate-year-one resident (PGY1), 264 postgraduate-year-two resident (PGY2), and 193 postgraduate-year-three resident (PGY3) shifts were included. PGY1s signed out 1.9 patients per 12-hour shift. PGY2s signed out 2.3 patients on 12-hour shifts and 1.8 patients on 9-hour shifts. PGY3s signed out 2.1 patients on 12-hour shifts and 2.0 patients on 9-hour shifts. When we controlled for patients seen per hour, SO burden was constant by class regardless of shift length, with PGY2s signing out 18% of patients seen compared to 15% for PGY3s. PGY1s signed out 18% of patients seen. TAT for patients seen by PGY1s and PGY2s was similar, at 189 and 187 minutes, respectively. TAT for patients seen by PGY3s was significantly less at 175 minutes. The additional hour devoted to wrapping up patients in the ED had no affect on SO burden. The SO burden represented a fixed percentage of the total number of patients seen by the residents. PGY3s sign-out a smaller percentage of patients seen compared to other classes, and have faster TATs.

Dedicated Shift Wrap-up Time Does Not Improve Resident Sign-out Volume or Efficiency

Directory of Open Access Journals (Sweden)

Jeanmonod, Rebecca K

2010-02-01

Full Text Available Objectives: Sign-out (SO is a challenge to the emergency physician. Some training programs have instituted overlapping 9-hour shifts. The residents see patients for eight hours, and have one hour of wrap-up time. This hour helps them complete patient care, leaving fewer patients to sign-out. We examined whether this strategy impacts SO burden.Methods: This is a retrospective review of patients evaluated by emergency medicine (EM residents working 9-hour (eight hours of patient care, one hour wrap-up time and 12-hour shifts (12 hours patient care, no reserved time for wrap-up. Data were collected by reviewing the clinical tracker. A patient was assigned to the resident who initiated care and dictated the chart. SO was defined as any patient in the ED without disposition at change of shift. Patient turn-around-time (TAT was also recorded.Results: One-hundred sixty-one postgraduate-year-one resident (PGY1, 264 postgraduate-year-two resident (PGY2, and 193 postgraduate-year-three resident (PGY3 shifts were included. PGY1s signed out 1.9 patients per 12-hour shift. PGY2s signed out 2.3 patients on 12-hour shifts and 1.8 patients on 9-hour shifts. PGY3s signed out 2.1 patients on 12-hour shifts and 2.0 patients on 9-hour shifts. When we controlled for patients seen per hour, SO burden was constant by class regardless of shift length, with PGY2s signing out 18% of patients seen compared to 15% for PGY3s. PGY1s signed out 18% of patients seen. TAT for patients seen by PGY1s and PGY2s was similar, at 189 and 187 minutes, respectively. TAT for patients seen by PGY3s was significantly less at 175 minutes.Conclusion: The additional hour devoted to wrapping up patients in the ED had no affect on SO burden. The SO burden represented a fixed percentage of the total number of patients seen by the residents. PGY3s sign-out a smaller percentage of patients seen compared to other classes, and have faster TATs. [West J Emerg Med. 2010; 11(1:35-39].

Space-time complexity in solid state models

International Nuclear Information System (INIS)

Bishop, A.R.

1985-01-01

In this Workshop on symmetry-breaking it is appropriate to include the evolving fields of nonlinear-nonequilibrium systems in which transitions to and between various degrees of ''complexity'' (including ''chaos'') occur in time or space or both. These notions naturally bring together phenomena of pattern formation and chaos and therefore have ramifications for a huge array of natural sciences - astrophysics, plasmas and lasers, hydrodynamics, field theory, materials and solid state theory, optics and electronics, biology, pattern recognition and evolution, etc. Our particular concerns here are with examples from solid state and condensed matter

Meteorologic, oceanographic, and geomorphic controls on circulation and residence time in a coral reef-lined embayment: Faga'alu Bay, American Samoa

Science.gov (United States)

Storlazzi, C. D.; Cheriton, O. M.; Messina, A. M.; Biggs, T. W.

2018-06-01

Water circulation over coral reefs can determine the degree to which reef organisms are exposed to the overlying waters, so understanding circulation is necessary to interpret spatial patterns in coral health. Because coral reefs often have high geomorphic complexity, circulation patterns and the duration of exposure, or "local residence time" of a water parcel, can vary substantially over small distances. Different meteorologic and oceanographic forcings can further alter residence time patterns over reefs. Here, spatially dense Lagrangian surface current drifters and Eulerian current meters were used to characterize circulation patterns and resulting residence times over different regions of the reefs in Faga'alu Bay, American Samoa, during three distinct forcing periods: calm, strong winds, and large waves. Residence times varied among different geomorphic zones of the reef and were reflected in the spatially varying health of the corals across the embayment. The relatively healthy, seaward fringing reef consistently had the shortest residence times, as it was continually flushed by wave breaking at the reef crest, whereas the degraded, sheltered, leeward fringing reef consistently had the longest residence times, suggesting this area is more exposed to land-based sources of pollution. Strong wind forcing resulted in the longest residence times by pinning the water in the bay, whereas large wave forcing flushed the bay and resulted in the shortest residence times. The effect of these different forcings on residence times was fairly consistent across all reef geomorphic zones, with the shift from wind to wave forcing shortening mean residence times by approximately 50%. Although ecologically significant to the coral organisms in the nearshore reef zones, these shortened residence times were still 2-3 times longer than those associated with the seaward fringing reef across all forcing conditions, demonstrating how the geomorphology of a reef environment sets a

A miniature CSTR cascade for continuous flow of reactions containing solids

OpenAIRE

Mo, Yiming; Jensen, Klavs F

2016-01-01

Continuous handling of solids creates challenges for realizing continuous production of pharmaceuticals and fine chemicals. We present a new miniature continuous stirred-tank reactor (CSTR) cascade to handle solid-forming reactions in flow. Single-phase residence time distribution (RTD) measurements of the CSTR cascade reveal nearly ideal CSTR mixing behavior of the individual units. Consistency of experimental and predicted conversions of a Diels–Alder reaction further confirms the CSTR perf...

Defining and measuring the mean residence time of lateral surface transient storage zones in small streams

Science.gov (United States)

T.R. Jackson; R. Haggerty; S.V. Apte; A. Coleman; K.J. Drost

2012-01-01

Surface transient storage (STS) has functional significance in stream ecosystems because it increases solute interaction with sediments. After volume, mean residence time is the most important metric of STS, but it is unclear how this can be measured accurately or related to other timescales and field-measureable parameters. We studied mean residence time of lateral...

Academic time at a level 1 trauma center: no resident, no problem?

Science.gov (United States)

Matsushima, Kazuhide; Dickinson, Rebecca M; Schaefer, Eric W; Armen, Scott B; Frankel, Heidi L

2012-01-01

Globally, the compliance of resident work-hour restrictions has no impact on trauma outcome. However, the effect of protected education time (PET), during which residents are unavailable to respond to trauma patients, has not been studied. We hypothesized that PET has no impact on the outcome of trauma patients. We conducted a retrospective review of relevant patients at an academic level I trauma center. During PET, a trauma attending and advanced practice providers (APPs) responded to trauma activations. PGY1, 3, and 4 residents were also available at all other times. The outcome of new trauma patient activations during Thursday morning 3-hours resident PET was compared with same time period on other weekdays (non-PET) using a univariate and multivariate analysis. From January 2005 to April 2010, a total of 5968 trauma patients were entered in the registry. Of these, 178 patients (2.98%) were included for study (37 PET and 141 non-PET). The mean injury severity score (ISS) was 16.2. Although no significant difference were identified in mortality, complications, or length of stay (LOS), we do see that length of emergency department stay (ED-LOS) tends to be longer during PET, although not significantly (314 vs 381 minutes, p = 0.74). On the multiple logistic regression model, PET was not a significant factor of complications, LOS, or ED-LOS. Few trauma activations occur during PET. New trauma activations can be staffed safely by trauma activations and APPs. However, there could be some delays in transferring patients to appropriate disposition. Additional study is required to determine the effect of PET on existing trauma inpatients. Copyright © 2012 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Geometrical effects on the electron residence time in semiconductor nano-particles.

Science.gov (United States)

Koochi, Hakimeh; Ebrahimi, Fatemeh

2014-09-07

We have used random walk (RW) numerical simulations to investigate the influence of the geometry on the statistics of the electron residence time τ(r) in a trap-limited diffusion process through semiconductor nano-particles. This is an important parameter in coarse-grained modeling of charge carrier transport in nano-structured semiconductor films. The traps have been distributed randomly on the surface (r(2) model) or through the whole particle (r(3) model) with a specified density. The trap energies have been taken from an exponential distribution and the traps release time is assumed to be a stochastic variable. We have carried out (RW) simulations to study the effect of coordination number, the spatial arrangement of the neighbors and the size of nano-particles on the statistics of τ(r). It has been observed that by increasing the coordination number n, the average value of electron residence time, τ̅(r) rapidly decreases to an asymptotic value. For a fixed coordination number n, the electron's mean residence time does not depend on the neighbors' spatial arrangement. In other words, τ̅(r) is a porosity-dependence, local parameter which generally varies remarkably from site to site, unless we are dealing with highly ordered structures. We have also examined the effect of nano-particle size d on the statistical behavior of τ̅(r). Our simulations indicate that for volume distribution of traps, τ̅(r) scales as d(2). For a surface distribution of traps τ(r) increases almost linearly with d. This leads to the prediction of a linear dependence of the diffusion coefficient D on the particle size d in ordered structures or random structures above the critical concentration which is in accordance with experimental observations.

Using just-in-time teaching and peer instruction in a residency program's core curriculum: enhancing satisfaction, engagement, and retention.

Science.gov (United States)

Schuller, Mary C; DaRosa, Debra A; Crandall, Marie L

2015-03-01

To assess use of the combined just-in-time teaching (JiTT) and peer instruction (PI) instructional strategy in a residency program's core curriculum. In 2010-2011, JiTT/PI was piloted in 31 core curriculum sessions taught by 22 faculty in the Northwestern University Feinberg School of Medicine's general surgery residency program. JiTT/PI required preliminary and categorical residents (n=31) to complete Web-based study questions before weekly specialty topic sessions. Responses were examined by faculty members "just in time" to tailor session content to residents' learning needs. In the sessions, residents answered multiple-choice questions (MCQs) using clickers and engaged in PI. Participants completed surveys assessing their perceptions of JiTT/PI. Videos were coded to assess resident engagement time in JiTT/PI sessions versus prior lecture-based sessions. Responses to topic session MCQs repeated in review sessions were evaluated to study retention. More than 70% of resident survey respondents indicated that JiTT/PI aided in the learning of key points. At least 90% of faculty survey respondents reported positive perceptions of aspects of the JiTT/PI strategy. Resident engagement time for JiTT/PI sessions was significantly greater than for prior lecture-based sessions (z=-2.4, P=.016). Significantly more review session MCQ responses were correct for residents who had attended corresponding JiTT/PI sessions than for residents who had not (chi-square=13.7; df=1; P<.001). JiTT/PI increased learner participation, learner retention, and the amount of learner-centered time. JiTT/PI represents an effective approach for meaningful and active learning in core curriculum sessions.

Spatial distribution of residence time, microbe and storage volume of groundwater in headwater catchments

Science.gov (United States)

Tsujimura, Maki; Ogawa, Mahiro; Yamamoto, Chisato; Sakakibara, Koichi; Sugiyama, Ayumi; Kato, Kenji; Nagaosa, Kazuyo; Yano, Shinjiro

2017-04-01

Headwater catchments in mountainous region are the most important recharge area for surface and subsurface waters, and time and stock information of the water is principal to understand hydrological processes in the catchments. Also, a variety of microbes are included in the groundwater and spring water, and those varies in time and space, suggesting that information of microbe could be used as tracer for groundwater flow system. However, there have been few researches to evaluate the relationship among the residence time, microbe and storage volume of the groundwater in headwater catchments. We performed an investigation on age dating using SF6 and CFCs, microbe counting in the spring water, and evaluation of groundwater storage volume based on water budget analysis in 8 regions underlain by different lithology, those are granite, dacite, sedimentary rocks, serpentinite, basalt and volcanic lava all over Japan. We conducted hydrometric measurements and sampling of spring water in base flow conditions during the rainless periods 2015 and 2016 in those regions, and SF6, CFCs, stable isotopic ratios of oxygen-18 and deuterium, inorganic solute concentrations and total number of prokaryotes were determined on all water samples. Residence time of spring water ranged from 0 to 16 years in all regions, and storage volume of the groundwater within topographical watershed was estimated to be 0.1 m to 222 m in water height. The spring with the longer residence time tends to have larger storage volume in the watershed, and the spring underlain by dacite tends to have larger storage volume as compared with that underlain by sand stone and chert. Also, total number of prokaryotes in the spring water ranged from 103 to 105 cells/mL, and the spring tends to show clear increasing of total number of prokaryotes with decreasing of residence time. Thus, we observed a certain relationship among residence time, storage volume and total number of prokaryotes in the spring water, and

Does residence time affect responses of alien species richness to environmental and spatial processes?

Directory of Open Access Journals (Sweden)

Matteo Dainese

2012-08-01

Full Text Available One of the most robust emerging generalisations in invasion biology is that the probability of invasion increases with the time since introduction (residence time. We analysed the spatial distribution of alien vascular plant species in a region of north-eastern Italy to understand the influence of residence time on patterns of alien species richness. Neophytes were grouped according to three periods of arrival in the study region (1500–1800, 1800–1900, and > 1900. We applied multiple regression (spatial and non-spatial with hierarchical partitioning to determine the influence of climate and human pressure on species richness within the groups. We also applied variation partitioning to evaluate the relative importance of environmental and spatial processes. Temperature mainly influenced groups with speciesa longer residence time, while human pressure influenced the more recently introduced species, although its influence remained significant in all groups. Partial regression analyses showed that most of the variation explained by the models is attributable to spatially structured environmental variation, while environment and space had small independent effects. However, effects independent of environment decreased, and spatially independent effects increased, from older to the more recent neophytes. Our data illustrate that the distribution of alien species richness for species that arrived recently is related to propagule pressure, availability of novel niches created by human activity, and neutral-based (dispersal limitation processes, while climate filtering plays a key role in the distribution of species that arrived earlier. This study highlights the importance of residence time, spatial structure, and environmental conditions in the patterns of alien species richness and for a better understanding of its geographical variation.

Groundwater residence time : tell me who you are and I will tell which information you may provide

Science.gov (United States)

Aquilina, Luc; Labasque, Thierry; Kolbe, Tamara; Marçais, Jean; Leray, Sarah; Abbott, Ben; de Dreuzy, Jean-Raynald

2016-04-01

Groundwater residence-time or ages have been widely used in hydrogeology during the last decades. Following tritium measurements, anthropogenic gases (CFC, SF6, 35Kr) have been developed. They provide information at the aquifer scale on long residence times. They complement the more localized data obtained from sparse boreholes with hydraulic and geophysical methods. Anthropogenic tracer concentrations are most generally considered as "Groundwater ages" using a piston flow model providing an order of magnitude for the residence time. More advanced information can however be derived from the combined analysis of the tracer concentrations. For example, the residence time distribution over the last 50 years can be well approached by the concentration of two sufficient different anthropogenic tracers in the group (CFC, SF6, 35Kr), i.e. tracers whose anthropogenic chronicles are sufficiently different. And, with additional constrains on geological and hydraulic properties, groundwater ages contribute to characterize the aquifer structures and the groundwater resources. Complex geological environments also include old groundwater bodies in extremely confined aquifer sections. In such cases, various tracers are related to highly different processes. CFCs can be taken as a marker of modern contamination to track exchanges between shallower and deeper aquifers, leakage processes, and modification of circulations linked to recent anthropogenic changes. 14C or 36Cl can be used to evidence much older processes but have to be related to the history of the chemical element itself. Numerous field studies in fact demonstrate the broad-range extent of the residence time distribution spanning in some cases several orders of magnitude. Flow and transport models in heterogeneous structures confirm such wide residence times and help to characterize their distribution. Residence times also serve as a privileged interface to the fate of some contaminants in aquifers or to trace

Modelling travel and residence times in the eastern Irish Sea

International Nuclear Information System (INIS)

Dabrowski, T.; Hartnett, M.

2008-01-01

The Irish Sea, which lies between 51 deg. N-56 deg. N and 2 deg. 50'W-7 deg. W, provides a sheltered environment to exploit valuable fisheries resource. Anthropogenic activity is a real threat to its water quality. The majority of freshwater input down rivers flows into the eastern Irish Sea. The structure of the water circulation was not well understood during the planning of Sellafield nuclear plant outfall site in the eastern Irish Sea. A three-dimensional primitive equation numerical model was applied to the Irish Sea to simulate both barotropic and baroclinic circulation within the region. High accuracy was achieved with regard to the prediction of both tidal circulation and surface and nearbed water temperatures across the region. The model properly represented the Western Irish Sea Gyre, induced by thermal stratification and not known during planning Sellafield. Passive tracer simulations based on the developed hydrodynamic model were used to deliver residence times of the eastern Irish Sea region for various times of the year as well as travel times from the Sellafield outfall site to various locations within the Irish Sea. The results indicate a strong seasonal variability of travel times from Sellafield to the examined locations. Travel time to the Clyde Sea is the shortest for the autumnal tracer release (90 days); it takes almost a year for the tracer to arrive at the same location if it is released in January. Travel times from Sellafield to Dublin Bay fall within the range of 180-360 days. The average residence time of the entire eastern Irish Sea is around 7 months. The areas surrounding the Isle of Man are initially flushed due to a predominant northward flow; a backwater is formed in Liverpool Bay. Thus, elevated tracer concentrations are predicted in Liverpool Bay in the case of accidental spills at the Sellafield outfall site

A survey of the influencing factors and models for resident's household waste management behavior

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

The problem of household solid waste has been concerned and researched on by municipalities and researchers.At present, household solid waste has been changed to management problem from technical one. From the point view of management, the research on household solid waste is to study the factors which influence resident's behavior of managtng their waste. Based on the literature review, firstly, this paper summarizes those factors which have already been identified to have impact on resident's behavior of managing their waste. They are social-demographic variables,knowledge, environmental values, psychological factors, publicity and system design. Secondly, three typical models of the relationship between factors and behavior, which are factors determining task performance in waste management,conceptualization of waste management behavior and the theoretical model of repeated behavior on household waste management, are analyzed and the deficiencies of these models are also analyzed. Finally, according to the current situation in household waste management and the culture and resident's habits in China, this paper puts forward a research focus and suggestions about resident 's behavior of household solid waste management.

Mean residence times of atmospheric aerosols in the boundary layer as determined from 210Bi/210Pb activity ratios

International Nuclear Information System (INIS)

Papastefanou, C.; Bondietti, E.A.

1991-01-01

Concentrations of radioactive 210 Pb and 210 Bi were measured in surface air after chemical separation and radiochemical analysis in an annual cycle and were used to determine aerosol residence times in the lower atmosphere. It was concluded that residence times of 8 days would apply to aerosols of 0.3 μm activity median aerodynamic diameter (AMAD). Cascade impactor data are also presented in relating the residence times and the AMAD of atmospheric aerosols. (author)

Study of gas-solid contact in an ultra-rapid reactor for cumene catalytic cracking; Etude du contact gaz-solide dans un reacteur a co-courant descendant par la mise en oeuvre du craquage catalytique du cumene

Energy Technology Data Exchange (ETDEWEB)

Bayle, J

1996-11-05

Few studies have been carried out on the notion of gas-solid contact in ultra-rapid reactors. Both gas and solid move in the reactor and the contact can be directly estimated when using a chemical reaction such as cumene cracking. It`s a pure and light feedstock whose kinetics can be determined in a fixed bed. The study was carried out on a downflow ultra-rapid reactor (ID = 20 mm, length = 1 m) at the University of Western Ontario. It proved that the quench and the ultra-rapid separation of gas and solid must be carefully designed in the pilot plant. Cumene conversion dropped when reducing gas-solid contact, which led to push the temperature over 550 deg. C and increase the cat/oil ratio at 25 working at solid mass fluxes below 85 kg/m{sup 2}.s. Change of selectivity at very short residence time were also observed due to deactivation effects. Experiments made by Roques (1994) with phosphorescent pigments on the Residence Time Distribution of solids gave Hydrodynamic data on a cold flow copy of the pilot plant. Experiments made on packed bed gave kinetic data on the cracking of cumene. These data were combined to optimize a mono dimensional plug flow model for cumene cracking. (author)

Real-Time Laser Ultrasound Tomography for Profilometry of Solids

Science.gov (United States)

Zarubin, V. P.; Bychkov, A. S.; Karabutov, A. A.; Simonova, V. A.; Kudinov, I. A.; Cherepetskaya, E. B.

2018-01-01

We studied the possibility of applying laser ultrasound tomography for profilometry of solids. The proposed approach provides high spatial resolution and efficiency, as well as profilometry of contaminated objects or objects submerged in liquids. The algorithms for the construction of tomograms and recognition of the profiles of studied objects using the parallel programming technology NDIVIA CUDA are proposed. A prototype of the real-time laser ultrasound profilometer was used to obtain the profiles of solid surfaces of revolution. The proposed method allows the real-time determination of the surface position for cylindrical objects with an approximation accuracy of up to 16 μm.

Factors influencing the residence time of catchment waters : A virtual experiment approach

NARCIS (Netherlands)

Dunn, S.M.; McDonnell, J.J.; Vaché, K.B.

Estimates of mean residence time (MRT) are increasingly used as simple summary descriptors of the hydrological processes involving storage and mixing of water within catchment systems. Current understanding of the physical controls on MRT remains limited, and various hypotheses have been proposed to

Determination of the hydraulic residence time of two subsurface-flow constructed wetlands using radiotracers

International Nuclear Information System (INIS)

Debien, Bruno R.

2013-01-01

The adoption of constructed wetland systems (CW's) with subsuperficial drainage for sewage treatment is increasingly growing in places with low technological resources and available land. The efficient removal of pollutants depends on the internal flow characteristics in the CW and on its hydraulic residence time (HRT). In the present work 82 Br - a gamma radiation emitter, produced from soluble potassium bromide irradiated in the TRIGA reactor at the Centre for the Development of Nuclear Energy (CDTN) - was used as a pseudo-conservative tracer for the comparative study of aqueous phase flow dynamics in two CW's: one in which plants were grown (WP) whereas the other had no plants (WNP). Experimental hydraulic residence time values were found to be very close to the theoretical one, while dispersion numbers obtained for both CW's were quite small. Besides these measured hydrodynamic parameters, the residence time distribution (RTD) curves of the tracer test and the results of modeling of experimental data also demonstrate the tendency of the units to display a plug flow-like effluent hydraulic transport within their systems, as expected from their designs, considering the large length/width ratio (L/W=8). (author)

Determination of the hydraulic residence time of two subsurface-flow constructed wetlands using radiotracers

Energy Technology Data Exchange (ETDEWEB)

Debien, Bruno R., E-mail: brunordebien@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept de Geografia. Lab. de Geomorfologia; Barreto, Alberto A.; Pinto, Amenonia M.F.; Moreira, Rubens M., E-mail: aab@cdtn.br, E-mail: amfp@cdtn.br, E-mail: rubens@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2013-07-01

The adoption of constructed wetland systems (CW's) with subsuperficial drainage for sewage treatment is increasingly growing in places with low technological resources and available land. The efficient removal of pollutants depends on the internal flow characteristics in the CW and on its hydraulic residence time (HRT). In the present work {sup 82}Br - a gamma radiation emitter, produced from soluble potassium bromide irradiated in the TRIGA reactor at the Centre for the Development of Nuclear Energy (CDTN) - was used as a pseudo-conservative tracer for the comparative study of aqueous phase flow dynamics in two CW's: one in which plants were grown (WP) whereas the other had no plants (WNP). Experimental hydraulic residence time values were found to be very close to the theoretical one, while dispersion numbers obtained for both CW's were quite small. Besides these measured hydrodynamic parameters, the residence time distribution (RTD) curves of the tracer test and the results of modeling of experimental data also demonstrate the tendency of the units to display a plug flow-like effluent hydraulic transport within their systems, as expected from their designs, considering the large length/width ratio (L/W=8). (author)

Seasonal variation of residence time in spring and groundwater evaluated by CFCs and numerical simulation in mountainous headwater catchment

Science.gov (United States)

Tsujimura, Maki; Watanabe, Yasuto; Ikeda, Koichi; Yano, Shinjiro; Abe, Yutaka

2016-04-01

Headwater catchments in mountainous region are the most important recharge area for surface and subsurface waters, additionally time information of the water is principal to understand hydrological processes in the catchments. However, there have been few researches to evaluate variation of residence time of subsurface water in time and space at the mountainous headwaters especially with steep slope. We investigated the temporal variation of the residence time of the spring and groundwater with tracing of hydrological flow processes in mountainous catchments underlain by granite, Yamanashi Prefecture, central Japan. We conducted intensive hydrological monitoring and water sampling of spring, stream and ground waters in high-flow and low-flow seasons from 2008 through 2013 in River Jingu Watershed underlain by granite, with an area of approximately 15 km2 and elevation ranging from 950 m to 2000 m. The CFCs, stable isotopic ratios of oxygen-18 and deuterium, inorganic solute constituent concentrations were determined on all water samples. Also, a numerical simulation was conducted to reproduce of the average residence times of the spring and groundwater. The residence time of the spring water estimated by the CFCs concentration ranged from 10 years to 60 years in space within the watershed, and it was higher (older) during the low flow season and lower (younger) during the high flow season. We tried to reproduce the seasonal change of the residence time in the spring water by numerical simulation, and the calculated residence time of the spring water and discharge of the stream agreed well with the observed values. The groundwater level was higher during the high flow season and the groundwater dominantly flowed through the weathered granite with higher permeability, whereas that was lower during the low flow season and that flowed dominantly through the fresh granite with lower permeability. This caused the seasonal variation of the residence time of the spring

Impact of Residency Training Redesign on Residents' Clinical Knowledge.

Science.gov (United States)

Waller, Elaine; Eiff, M Patrice; Dexter, Eve; Rinaldo, Jason C B; Marino, Miguel; Garvin, Roger; Douglass, Alan B; Phillips, Robert; Green, Larry A; Carney, Patricia A

2017-10-01

The In-training Examination (ITE) is a frequently used method to evaluate family medicine residents' clinical knowledge. We compared family medicine ITE scores among residents who trained in the 14 programs that participated in the Preparing the Personal Physician for Practice (P4) Project to national averages over time, and according to educational innovations. The ITE scores of 802 consenting P4 residents who trained in 2007 through 2011 were obtained from the American Board of Family Medicine. The primary analysis involved comparing scores within each academic year (2007 through 2011), according to program year (PGY) for P4 residents to all residents nationally. A secondary analysis compared ITE scores among residents in programs that experimented with length of training and compared scores among residents in programs that offered individualized education options with those that did not. Release of ITE scores was consented to by 95.5% of residents for this study. Scores of P4 residents were higher compared to national scores in each year. For example, in 2011, the mean P4 score for PGY1 was 401.2, compared to the national average of 386. For PGY2, the mean P4 score was 443.1, compared to the national average of 427, and for PGY3, the mean P4 score was 477.0, compared to the national PGY3 score of 456. Scores of residents in programs that experimented with length of training were similar to those in programs that did not. Scores were also similar between residents in programs with and without individualized education options. Family medicine residency programs undergoing substantial educational changes, including experiments in length of training and individualized education, did not appear to experience a negative effect on resident's clinical knowledge, as measured by ITE scores. Further research is needed to study the effect of a wide range of residency training innovations on ITE scores over time.

Conformational Network and Residence Time Estimation of Trypsin-Benzamidine Unbinding Pathways

OpenAIRE

Dickson, Alex; Lotz, Samuel D.

2016-01-01

In this poster we present results from molecular dynamics sampling of benzamidine unbinding from trypsin. We give background on the weighted ensemble technique used (WExplore) and the Markovian state model construction. Our network shows three unique unbinding pathways including a never before observed unbinding pathway. We also estimate residence time to within one order of magnitude to the experimental value.

Long residence times - bad tracer tests?

Science.gov (United States)

Ghergut, Julia; Behrens, Horst; Sauter, Martin

2015-04-01

Tracer tests conducted at geothermal well doublets or triplets in the Upper Rhine Rift Valley [1] all face, with very few exceptions so far, one common issue: lack of conclusive tracer test results, or tracer signals still undetectable for longer than one or two years after tracer injection. While the reasons for this surely differ from site to site (Riehen, Landau, Insheim, Bruchsal, ...), its effects on how the usefulness of tracer tests is perceived by the non-tracer community are pretty much the same. The 'poor-signal' frustration keeps nourishing two major 'alternative' endeavours : (I) design and execute tracer tests in single-well injection-withdrawal (push-pull), 'instead of' inter-well flow-path tracing configurations; (II) use 'novel' tracer substances instead of the 'old' ones which have 'obviously failed'. Frustration experienced with most inter-well tracer tests in the Upper Rhine Rift Valley has also made them be regarded as 'maybe useful for EGS' ('enhanced', or 'engineered' geothermal systems, whose fluid RTD typically include a major share of values below one year), but 'no longer worthwhile a follow-up sampling' in natural, large-scale hydrothermal reservoirs. We illustrate some of these arguments with the ongoing Bruchsal case [2]. The inter-well tracer test conducted at Bruchsal was (and still is!) aimed at assessing inter-well connectivity, fluid residence times, and characterizing the reservoir structure [3]. Fluid samples taken at the geothermal production well after reaching a fluid turnover of about 700,000 m3 showed tracer concentrations in the range of 10-8 Minj per m3, in the liquid phase of each sample (Minj being the total quantity of tracer injected as a short pulse at the geothermal re-injection well). Tracer signals might actually be higher, owing to tracer amounts co-precipitated and/or adsorbed onto the solid phase whose accumulation in the samples was unavoidable (due to pressure relief and degassing during the very sampling

Comparison of the tritium residence times of various ceramic breeder materials irradiated in EXOTIC experiments 4 and 5

International Nuclear Information System (INIS)

Kwast, H.; Elen, J.D.; Conrad, R.; Casadio, S.; Werle, H.; Verstappen, G.

1990-09-01

Tritium residence times have been determined for various ceramic tritium breeding materials from in-situ release measurements. The irradiations, codenamed EXOTIC (EXtraction Of Tritium In Ceramics), were carried out in the High Flux Reactor (HFR) Petten. During the irradiation more than 450 transients were performed and the corresponding tritium release measured. Materials supplied by SCK/CEN (Li 2 ZrO 3 ), CEA (Li 2 ZrO 3 and LiAlO 2 ), ENEA (LiAlO 2 ), KfK (Li 4 SiO 4 ), NRL (Li 6 Zr 2 O 7 ) and ECN (Li 8 ZrO 6 ) were irradiated in EXOTIC-5 to compare the tritium residence times obtained under equal conditions. Apart from differences in density, grain size, pore size and OPV it appeared that the tritium residence times of the lithium zirconates (pellets) were shorter than those of the Li 4 SiO 4 pebbles. The tritium residence times of the Li 4 SiO 4 pebbles were shorter than those of the LiAlO 2 pellets. (author). 7 refs.; 5 figs.; 3 tabs

Using continuous underway isotope measurements to map water residence time in hydrodynamically complex tidal environments

Science.gov (United States)

Downing, Bryan D.; Bergamaschi, Brian; Kendall, Carol; Kraus, Tamara; Dennis, Kate J.; Carter, Jeffery A.; von Dessonneck, Travis

2016-01-01

Stable isotopes present in water (δ2H, δ18O) have been used extensively to evaluate hydrological processes on the basis of parameters such as evaporation, precipitation, mixing, and residence time. In estuarine aquatic habitats, residence time (τ) is a major driver of biogeochemical processes, affecting trophic subsidies and conditions in fish-spawning habitats. But τ is highly variable in estuaries, owing to constant changes in river inflows, tides, wind, and water height, all of which combine to affect τ in unpredictable ways. It recently became feasible to measure δ2H and δ18O continuously, at a high sampling frequency (1 Hz), using diffusion sample introduction into a cavity ring-down spectrometer. To better understand the relationship of τ to biogeochemical processes in a dynamic estuarine system, we continuously measured δ2H and δ18O, nitrate and water quality parameters, on board a small, high-speed boat (5 to >10 m s–1) fitted with a hull-mounted underwater intake. We then calculated τ as is classically done using the isotopic signals of evaporation. The result was high-resolution (∼10 m) maps of residence time, nitrate, and other parameters that showed strong spatial gradients corresponding to geomorphic attributes of the different channels in the area. The mean measured value of τ was 30.5 d, with a range of 0–50 d. We used the measured spatial gradients in both τ and nitrate to calculate whole-ecosystem uptake rates, and the values ranged from 0.006 to 0.039 d–1. The capability to measure residence time over single tidal cycles in estuaries will be useful for evaluating and further understanding drivers of phytoplankton abundance, resolving differences attributable to mixing and water sources, explicitly calculating biogeochemical rates, and exploring the complex linkages among time-dependent biogeochemical processes in hydrodynamically complex environments such as estuaries.

Fertilizer residence time affects nitrogen uptake efficiency and growth of sweet corn

NARCIS (Netherlands)

Zotarelli, L.; Scholberg, J.M.S.; Dukes, M.D.; Munoz-Carpena, R.

2008-01-01

Understanding plant N uptake dynamics is critical for increasing fertilizer N uptake efficiency (FUE) and minimize the risk of N leaching. The objective of this research was to determine the effect of residence time of N fertilizer on N uptake and FUE of sweet corn. Plants were grown in 25 L columns

Solid Fuel in Kitchen and Acute Respiratory Tract Infection Among Under Five Children

DEFF Research Database (Denmark)

Acharya, Pawan; Mishra, Shiva Raj; Berg-Beckhoff, Gabriele

2015-01-01

adjusting for age, sex, birth order, urban/rural residence, ecological zone, development region, economic status, number of family members, mother's smoking status and mother's education, odds of suffering from ARI was 1.79 times higher among the children from the households using solid fuel in comparison...

Timed Up And Go Risk Predictor Of Falls In Elderly People Residing In The Community?

Directory of Open Access Journals (Sweden)

Mayara Muniz Peixoto Rodrigues

2017-04-01

Full Text Available Objective: evaluate the risk of falls of elderly people residing in a community in northeastern Brazil using the “Timed up and go”. Method: descriptive study, with a quantitative approach, performed with elderly people residing in a community. The collected data related to the sociodemographic and economic characteristics of episodes of falls in the last two years, regular practice of physical exercise and complaint of pain at the time of the interview; and, at last, the application of the “Timed Up and Go” test. Result: Most of the elderly were classified as free and independent and independent. There is a direct relationship between advanced age and increased time to perform the test. Conclusion: the "Timed Up and Go" test was not effective in predicting risk of falls alone and should associate with other indicators. Descriptors: Elderly people; Accidents by fall; Walking; Postural balance.

Uncertainties in carbon residence time and NPP-driven carbon uptake in terrestrial ecosystems of the conterminous USA: a Bayesian approach

Directory of Open Access Journals (Sweden)

Xuhui Zhou

2012-10-01

Full Text Available Carbon (C residence time is one of the key factors that determine the capacity of ecosystem C storage. However, its uncertainties have not been well quantified, especially at regional scales. Assessing uncertainties of C residence time is thus crucial for an improved understanding of terrestrial C sequestration. In this study, the Bayesian inversion and Markov Chain Monte Carlo (MCMC technique were applied to a regional terrestrial ecosystem (TECO-R model to quantify C residence times and net primary productivity (NPP-driven ecosystem C uptake and assess their uncertainties in the conterminous USA. The uncertainty was represented by coefficient of variation (CV. The 13 spatially distributed data sets of C pools and fluxes have been used to constrain TECO-R model for each biome (totally eight biomes. Our results showed that estimated ecosystem C residence times ranged from 16.6±1.8 (cropland to 85.9±15.3 yr (evergreen needleleaf forest with an average of 56.8±8.8 yr in the conterminous USA. The ecosystem C residence times and their CV were spatially heterogeneous and varied with vegetation types and climate conditions. Large uncertainties appeared in the southern and eastern USA. Driven by NPP changes from 1982 to 1998, terrestrial ecosystems in the conterminous USA would absorb 0.20±0.06 Pg C yr−1. Their spatial pattern was closely related to the greenness map in the summer with larger uptake in central and southeast regions. The lack of data or timescale mismatching between the available data and the estimated parameters lead to uncertainties in the estimated C residence times, which together with initial NPP resulted in the uncertainties in the estimated NPP-driven C uptake. The Bayesian approach with MCMC inversion provides an effective tool to estimate spatially distributed C residence time and assess their uncertainties in the conterminous USA.

Rational optimization of drug-target residence time: Insights from inhibitor binding to the S. aureus FabI enzyme-product complex

Science.gov (United States)

Chang, Andrew; Schiebel, Johannes; Yu, Weixuan; Bommineni, Gopal R.; Pan, Pan; Baxter, Michael V.; Khanna, Avinash; Sotriffer, Christoph A.; Kisker, Caroline; Tonge, Peter J.

2013-01-01

Drug-target kinetics has recently emerged as an especially important facet of the drug discovery process. In particular, prolonged drug-target residence times may confer enhanced efficacy and selectivity in the open in vivo system. However, the lack of accurate kinetic and structural data for series of congeneric compounds hinders the rational design of inhibitors with decreased off-rates. Therefore, we chose the Staphylococcus aureus enoyl-ACP reductase (saFabI) - an important target for the development of new anti-staphylococcal drugs - as a model system to rationalize and optimize the drug-target residence time on a structural basis. Using our new, efficient and widely applicable mechanistically informed kinetic approach, we obtained a full characterization of saFabI inhibition by a series of 20 diphenyl ethers complemented by a collection of 9 saFabI-inhibitor crystal structures. We identified a strong correlation between the affinities of the investigated saFabI diphenyl ether inhibitors and their corresponding residence times, which can be rationalized on a structural basis. Due to its favorable interactions with the enzyme, the residence time of our most potent compound exceeds 10 hours. In addition, we found that affinity and residence time in this system can be significantly enhanced by modifications predictable by a careful consideration of catalysis. Our study provides a blueprint for investigating and prolonging drug-target kinetics and may aid in the rational design of long-residence-time inhibitors targeting the essential saFabI enzyme. PMID:23697754

Origin and residence time of water in the Lima aquifer

International Nuclear Information System (INIS)

Montoya, Modesto; Mamani, Enoc

2013-01-01

The 8 million inhabitants of the coastal city Lima are supplied with water from the Rimac and Chillon rivers and water wells in the Lima aquifer. The history of the Rimac River flow and static level of water in its wells have been correlated to calculate the residence time of water in the aquifer it is recharged by the Rimac River until it reaches a well located 12 km away in the Miraflores District near the sea. The relative abundance of 2 H and 18 O are used to identify the origins of the waters from those wells, and the 3 H and 14 C contents are used to estimate the time after they fall as rain. (authors).

Plan for radionuclide tracer studies of the residence time distribution in the Wilsonville dissolver and preheater

International Nuclear Information System (INIS)

Jolley, R.L.; Begovich, J.M.; Brashear, H.R.

1983-12-01

Stimulus-response measurements using radiotracers to measure residence time distribution (RTD) and hydrodynamic parameters for the preheaters and dissolvers at the Ft. Lewis Solvent Refined Coal (SRC) and the Exxon Donor Solvent (EDS) coal conversion pilot plants are reviewed. A plan is also presented for a series of radioactive tracer studies proposed for the Advanced Coal Liquefaction Facility at Wilsonville, Alabama, to measure the RTD for the preheater and dissolvers in the SRC-I mode. The tracer for the gas phase will be 133 Xe, and 198 Au (on carbonized resin or as an aqueous colloidal suspension) will be used as the slurry tracer. Four experimental phases are recommended for the RTD tracer studies: (1) preheater; (2) dissolver with 100% takeoff; (3) dissolver with 100% takeoff and solids withdrawal; and (4) dissolver with 50% takeoff. Eighteen gas-tracer and 22 liquid-tracer injections are projected to accomplish the four experimental phases. Two to four tracer injections are projected for preliminary tests to ensure the capability of safe injection of the radiotracers and the collection of statistically significant data. A complete projected cost and time schedule is provided, including procurement of necessary components, preparation of the radiotracers, assembly and testing of tracer injection apparatus and detection systems, onsite work and tracer injections, laboratory experimentation, data analysis, and report writing

Tritium activity concentrations and residence times of groundwater collected in Rokkasho, Japan

International Nuclear Information System (INIS)

Hasegawa, Hidenao; Ueda, Shinji; Kakiuchi, Hideki; Hisamatsu, Shun'ichi; Akata, Naofumi

2015-01-01

Tritium ( 3 H) concentrations were measured in groundwater samples from four surface wells (4-10 m deep), four shallow wells (24-26.5 m deep) and a 150-m-deep well in the Futamata River catchment area, which is adjacent to the large-scale commercial spent nuclear fuel reprocessing plant in Rokkasho, Japan. The 3 H concentrations in most of the surface- and shallow-well samples (<0.03-0.57 Bq l -1 ) were similar to those in precipitation (annual mean: 0.31-0.79 Bq l -1 ), suggesting that the residence time of the water in those wells was 0-15 y. The 3 H concentrations in the samples from a 26-m-deep well and the 150-m-deep well were lower than those in the other wells, indicating that groundwater with a long residence time exists in deep aquifers and the estuary area of the catchment. It is not clear whether 3 H released during test operation of the plant with actual spent nuclear fuel affected the 3 H concentrations observed in this study. (authors)

Residence time of pollutants discharged in the Gulf of Kachchh, northwestern Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

Patgaonkar, R.S.; Vethamony, P.; Lokesh, K.S.; Babu, M.T.

A 2D Hydrodynamic-Particle Analysis model was applied to the Gulf of Kachchh (GoK) to estimate the residence time of pollutants. The tidal currents in the Gulf have a strong E-W component, which prevents the material in the north being transported...

Investigation of Residence and Travel Times in a Large Floodplain Lake with Complex Lake-River Interactions: Poyang Lake (China

Directory of Open Access Journals (Sweden)

Yunliang Li

2015-04-01

Full Text Available Most biochemical processes and associated water quality in lakes depends on their flushing abilities. The main objective of this study was to investigate the transport time scale in a large floodplain lake, Poyang Lake (China. A 2D hydrodynamic model (MIKE 21 was combined with dye tracer simulations to determine residence and travel times of the lake for various water level variation periods. The results indicate that Poyang Lake exhibits strong but spatially heterogeneous residence times that vary with its highly seasonal water level dynamics. Generally, the average residence times are less than 10 days along the lake’s main flow channels due to the prevailing northward flow pattern; whereas approximately 30 days were estimated during high water level conditions in the summer. The local topographically controlled flow patterns substantially increase the residence time in some bays with high spatial values of six months to one year during all water level variation periods. Depending on changes in the water level regime, the travel times from the pollution sources to the lake outlet during the high and falling water level periods (up to 32 days are four times greater than those under the rising and low water level periods (approximately seven days.

Agro-industrial waste to solid biofuel through hydrothermal carbonization.

Science.gov (United States)

Basso, Daniele; Patuzzi, Francesco; Castello, Daniele; Baratieri, Marco; Rada, Elena Cristina; Weiss-Hortala, Elsa; Fiori, Luca

2016-01-01

In this paper, the use of grape marc for energy purposes was investigated. Grape marc is a residual lignocellulosic by-product from the winery industry, which is present in every world region where vine-making is addressed. Among the others, hydrothermal carbonization was chosen as a promising alternative thermochemical process, suitable for the treatment of this high moisture substrate. Through a 50 mL experimental apparatus, hydrothermal carbonization tests were performed at several temperatures (namely: 180, 220 and 250 °C) and residence times (1, 3, 8 h). Analyses on both the solid and the gaseous phases obtained downstream of the process were performed. In particular, solid and gas yields versus the process operational conditions were studied and the obtained hydrochar was evaluated in terms of calorific value, elemental analysis, and thermal stability. Data testify that hydrochar form grape marc presents interesting values of HHV (in the range 19.8-24.1 MJ/kg) and physical-chemical characteristics which make hydrochar exploitable as a solid biofuel. In the meanwhile, the amount of gases produced is very small, if compared to other thermochemical processes. This represents an interesting result when considering environmental issues. Statistical analysis of data allows to affirm that, in the chosen range of operational conditions, the process is influenced more by temperature than residence time. These preliminary results support the option of upgrading grape marc toward its energetic valorisation through hydrothermal carbonization. Copyright © 2015 Elsevier Ltd. All rights reserved.

Motives as predictors of the public's attitudes toward solid waste issues

Energy Technology Data Exchange (ETDEWEB)

Ebreo, A.; Vining, J.

2000-02-01

Surveys focusing on solid-waste-related issues, conducted over a period of several years, provided data from independent samples of residents of a Midwestern, USA, community. The collection of these data yielded useful information about the relationship between residents' recycling motives and their attitudes toward solid waste management in light of several changes in the solid waste infrastructure of the community over that time. The initial survey assessed baseline beliefs and attitudes, while later surveys were conducted after the implementation of a community educational program and a curbside recycling program. The findings indicated that for recyclers and nonrecyclers, different motives predicted endorsement of solid waste programs and policies. Although a similar percentage of recyclers and nonrecyclers were in support of various proposed programs and policies, concern for the environment was found to be positively related to nonrecyclers' support of proposed programs, particularly before these programs were implemented. Prior to program implementation, motives other than environmental altruism were found to be related to recyclers' support of the programs. Additional findings support the idea that educational programs and increased accessibility to recycling opportunities affect the relationship between people's attitudes toward solid waste management and their recycling motives.

Origin and residence time of water in the Lima Aquifer

OpenAIRE

Montoya, Modesto; Mamani, Enoc

2014-01-01

The 8 million inhabitants of the coastal city Lima are supplied with water from the Rimac and Chillon rivers and water wells in the Lima aquifer. The history of the Rimac River flow and static level of water in its wells have been correlated to calculate the residence time of water in the aquifer it is recharged by the Rimac River until it reaches a well located 12 km away in the Miraflores District near the sea. The relative abundance of H-2 and O-18 are used to identify the origins of the w...

Effects of Time, Heat, and Oxygen on K Basin Sludge Agglomeration, Strength, and Solids Volume

Energy Technology Data Exchange (ETDEWEB)

Delegard, Calvin H.; Sinkov, Sergey I.; Schmidt, Andrew J.; Daniel, Richard C.; Burns, Carolyn A.

2011-01-04

Sludge disposition will be managed in two phases under the K Basin Sludge Treatment Project. The first phase is to retrieve the sludge that currently resides in engineered containers in the K West (KW) Basin pool at ~10 to 18°C. The second phase is to retrieve the sludge from interim storage in the sludge transport and storage containers (STSCs) and treat and package it in preparation for eventual shipment to the Waste Isolation Pilot Plant. The work described in this report was conducted to gain insight into how sludge may change during long-term containerized storage in the STSCs. To accelerate potential physical and chemical changes, the tests were performed at temperatures and oxygen partial pressures significantly greater than those expected in the T Plant canyon cells where the STSCs will be stored. Tests were conducted to determine the effects of 50°C oxygenated water exposure on settled quiescent uraninite (UO2) slurry and a full simulant of KW containerized sludge to determine the effects of oxygen and heat on the composition and mechanical properties of sludge. Shear-strength measurements by vane rheometry also were conducted for UO2 slurry, mixtures of UO2 and metaschoepite (UO3•2H2O), and for simulated KW containerized sludge. The results from these tests and related previous tests are compared to determine whether the settled solids in the K Basin sludge materials change in volume because of oxidation of UO2 by dissolved atmospheric oxygen to form metaschoepite. The test results also are compared to determine if heating or other factors alter sludge volumes and to determine the effects of sludge composition and settling times on sludge shear strength. It has been estimated that the sludge volume will increase with time because of a uranium metal → uraninite → metaschoepite oxidation sequence. This increase could increase the number of containers required for storage and increase overall costs of sludge management activities. However, the volume

Effects of Time, Heat, and Oxygen on K Basin Sludge Agglomeration, Strength, and Solids Volume

International Nuclear Information System (INIS)

Delegard, Calvin H.; Sinkov, Sergey I.; Schmidt, Andrew J.; Daniel, Richard C.; Burns, Carolyn A.

2011-01-01

Sludge disposition will be managed in two phases under the K Basin Sludge Treatment Project. The first phase is to retrieve the sludge that currently resides in engineered containers in the K West (KW) Basin pool at ∼10 to 18 C. The second phase is to retrieve the sludge from interim storage in the sludge transport and storage containers (STSCs) and treat and package it in preparation for eventual shipment to the Waste Isolation Pilot Plant. The work described in this report was conducted to gain insight into how sludge may change during long-term containerized storage in the STSCs. To accelerate potential physical and chemical changes, the tests were performed at temperatures and oxygen partial pressures significantly greater than those expected in the T Plant canyon cells where the STSCs will be stored. Tests were conducted to determine the effects of 50 C oxygenated water exposure on settled quiescent uraninite (UO 2 ) slurry and a full simulant of KW containerized sludge to determine the effects of oxygen and heat on the composition and mechanical properties of sludge. Shear-strength measurements by vane rheometry also were conducted for UO 2 slurry, mixtures of UO2 and metaschoepite (UO 3 · 2H 2 O), and for simulated KW containerized sludge. The results from these tests and related previous tests are compared to determine whether the settled solids in the K Basin sludge materials change in volume because of oxidation of UO2 by dissolved atmospheric oxygen to form metaschoepite. The test results also are compared to determine if heating or other factors alter sludge volumes and to determine the effects of sludge composition and settling times on sludge shear strength. It has been estimated that the sludge volume will increase with time because of a uranium metal → uraninite → metaschoepite oxidation sequence. This increase could increase the number of containers required for storage and increase overall costs of sludge management activities. However, the

Origin and residence time of water in the Lima aquifer

Energy Technology Data Exchange (ETDEWEB)

Montoya, Modesto [Instituto Peruano de Energia Nuclear, Av. Canada 1470, San Borja, Lima (Peru); Universidad Nacional de Ingenieria, Av. Tupac Amaru 210, Rimac, Lima (Peru); Mamani, Enoc [Direccion de Servicios, Instituto Peruano de Energia Nuclear, Av. Jose Saco km 12.5, Carabayllo, Lima (Peru)

2013-07-01

The 8 million inhabitants of the coastal city Lima are supplied with water from the Rimac and Chillon rivers and water wells in the Lima aquifer. The history of the Rimac River flow and static level of water in its wells have been correlated to calculate the residence time of water in the aquifer it is recharged by the Rimac River until it reaches a well located 12 km away in the Miraflores District near the sea. The relative abundance of {sup 2}H and {sup 18}O are used to identify the origins of the waters from those wells, and the {sup 3}H and {sup 14}C contents are used to estimate the time after they fall as rain. (authors).

Keeping up with the times: revising the dermatology residency curriculum in the era of molecular diagnostics and personalized medicine.

Science.gov (United States)

LaChance, Avery; Murphy, Michael J

2014-11-01

The clinical use of molecular diagnostics, genomics, and personalized medicine is increasing and improving rapidly over time. However, medical education incorporating the practical application of these techniques is lagging behind. Although instruction in these areas should be expanded upon and improved at all levels of training, residency provides a concentrated period of time in which to hone in on skills that are practically applicable to a trainee's specialty of choice. Although residencies in some fields, such as pathology, have begun to incorporate practical molecular diagnostics training, this area remains a relative gap in dermatology residency programs. Herein, we advocate for the incorporation of training in molecular diagnostics and personalized medicine into dermatology residency programs and propose a basic curriculum template for how to begin approaching these topics. By incorporating molecular diagnostics into dermatology residency training, dermatologists have the opportunity to lead the way and actively shape the specialty's transition into the era of personalized medicine. © 2014 The International Society of Dermatology.

A time-efficient web-based teaching tool to improve medical knowledge and decrease ABIM failure rate in select residents.

Science.gov (United States)

Drake, Sean M; Qureshi, Waqas; Morse, William; Baker-Genaw, Kimberly

2015-01-01

The American Board of Internal Medicine (ABIM) exam's pass rate is considered a quality measure of a residency program, yet few interventions have shown benefit in reducing the failure rate. We developed a web-based Directed Reading (DR) program with an aim to increase medical knowledge and reduce ABIM exam failure rate. Internal medicine residents at our academic medical center with In-Training Examination (ITE) scores ≤ 35 th percentile from 2007 to 2013 were enrolled in DR. The program matches residents to reading assignments based on their own ITE-failed educational objectives and provides direct electronic feedback from their teaching physicians. ABIM exam pass rates were analyzed across various groups between 2002 and 2013 to examine the effect of the DR program on residents with ITE scores ≤ 35 percentile pre- (2002-2006) and post-intervention (2007-2013). A time commitment survey was also given to physicians and DR residents at the end of the study. Residents who never scored ≤ 35 percentile on ITE were the most likely to pass the ABIM exam on first attempt regardless of time period. For those who ever scored ≤ 35 percentile on ITE, 91.9% of residents who participated in DR passed the ABIM exam on first attempt vs 85.2% of their counterparts pre-intervention (p ITE were more likely to fail ABIM exam on first attempt, those who participated in the DR program were less likely to fail than the historical control counterparts. The web-based teaching method required little time commitment by faculty.

Solid waste management in Kolkata, India: Practices and challenges

International Nuclear Information System (INIS)

Hazra, Tumpa; Goel, Sudha

2009-01-01

This paper presents an overview of current solid waste management (SWM) practices in Kolkata, India and suggests solutions to some of the major problems. More than 2920 ton/d of solid waste are generated in the Kolkata Municipal Corporation (KMC) area and the budget allocation for 2007-2008 was Rs. 1590 million (US$40 million), which amounts to Rs. 265/cap-y (US$6.7/cap-d) on SWM. This expenditure is insufficient to provide adequate SWM services. Major deficiencies were found in all elements of SWM. Despite 70% of the SWM budget being allocated for collection, collection efficiency is around 60-70% for the registered residents and less than 20% for unregistered residents (slum dwellers). The collection process is deficient in terms of manpower and vehicle availability. Bin capacity provided is adequate but locations were found to be inappropriate, thus contributing to the inefficiency of the system. At this time, no treatment is provided to the waste and waste is dumped on open land at Dhapa after collection. Lack of suitable facilities (equipment and infrastructure) and underestimates of waste generation rates, inadequate management and technical skills, improper bin collection, and route planning are responsible for poor collection and transportation of municipal solid wastes

Anesthesia preparation time is not affected by the experience level of the resident involved during his/her first month of adult cardiac surgery.

Science.gov (United States)

Broussard, David M; Couch, Michael C

2011-10-01

This study was designed to answer the question of whether the experience level of the resident on his/her first month of adult cardiothoracic anesthesiology has an impact on operating room efficiency in a large academic medical center. Traditionally, the resident's 1st month of cardiac anesthesia had been reserved for the clinical anesthesia (CA)-2 year of training. This study analyzed the impact on operating room efficiency of moving the 1st month of cardiac anesthesia into the CA-1 year. The authors hypothesized that there would be no difference in anesthesia preparation times (defined as the interval between "in-room" and "anesthesia-ready" times) between CA-1 and CA-2 residents on their 1st month of cardiac anesthesia. This study was retrospective and used an electronic anesthesia information management system database. This study was conducted on care provided at a single 450-bed academic medical center. This study included 12 residents in their 1st month of cardiac anesthesia. The anesthesia preparation time (defined as the interval between "in-room" and "anesthesia-ready" times) was measured for cases involving residents on their first month of cardiac anesthesia. Anesthesia preparation times for 6 CA-1 resident months and 6 CA-2 resident months (100 adult cardiac procedures in total) were analyzed (49 for the CA-1 residents and 51 for the CA-2s). There were no differences in preparation time between CA-1 and CA-2 residents as a group (p = 0.8169). The CA-1 residents had an unadjusted mean (±standard error) of 51.1 ± 3.18 minutes, whereas the CA-2 residents' unadjusted mean was 50.2 ± 2.41 minutes. Adjusting for case mix (valves v coronary artery bypass graft surgery), the CA-1 mean was 49.1 ± 5.22 minutes, whereas the CA-2 mean was 49.1 ± 4.54 minutes. These findings suggest that operating room efficiency as measured by the anesthesia preparation time may not be affected by the level of the resident on his/her 1st month of adult cardiac anesthesia

Results of the 2005-2008 Association of Residents in Radiation Oncology Survey of Chief Residents in the United States: Clinical Training and Resident Working Conditions

International Nuclear Information System (INIS)

Gondi, Vinai; Bernard, Johnny Ray; Jabbari, Siavash; Keam, Jennifer; Amorim Bernstein, Karen L. de; Dad, Luqman K.; Li, Linna; Poppe, Matthew M.; Strauss, Jonathan B.; Chollet, Casey T.

2011-01-01

Purpose: To document clinical training and resident working conditions reported by chief residents during their residency. Methods and Materials: During the academic years 2005 to 2006, 2006 to 2007, and 2007 to 2008, the Association of Residents in Radiation Oncology conducted a nationwide survey of all radiation oncology chief residents in the United States. Chi-square statistics were used to assess changes in clinical training and resident working conditions over time. Results: Surveys were completed by representatives from 55 programs (response rate, 71.4%) in 2005 to 2006, 60 programs (75.9%) in 2006 to 2007, and 74 programs (93.7%) in 2007 to 2008. Nearly all chief residents reported receiving adequate clinical experience in commonly treated disease sites, such as breast and genitourinary malignancies; and commonly performed procedures, such as three-dimensional conformal radiotherapy and intensity-modulated radiotherapy. Clinical experience in extracranial stereotactic radiotherapy increased over time (p < 0.001), whereas clinical experience in endovascular brachytherapy (p <0.001) decreased over time. The distribution of gynecologic and prostate brachytherapy cases remained stable, while clinical case load in breast brachytherapy increased (p = 0.006). A small but significant percentage of residents reported receiving inadequate clinical experience in pediatrics, seeing 10 or fewer pediatric cases during the course of residency. Procedures involving higher capital costs, such as particle beam therapy and intraoperative radiotherapy, and infrequent clinical use, such as head and neck brachytherapy, were limited to a minority of institutions. Most residency programs associated with at least one satellite facility have incorporated resident rotations into their clinical training, and the majority of residents at these programs find them valuable experiences. The majority of residents reported working 60 or fewer hours per week on required clinical duties

Orthopedic resident work-shift analysis: are we making the best use of resident work hours?

Science.gov (United States)

Hamid, Kamran S; Nwachukwu, Benedict U; Hsu, Eugene; Edgerton, Colston A; Hobson, David R; Lang, Jason E

2014-01-01

Surgery programs have been tasked to meet rising demands in patient surgical care while simultaneously providing adequate resident training in the midst of increasing resident work-hour restrictions. The purpose of this study was to quantify orthopedic surgery resident workflow and identify areas needing improved resident efficiency. We hypothesize that residents spend a disproportionate amount of time involved in activities that do not relate directly to patient care or maximize resident education. We observed 4 orthopedic surgery residents on the orthopedic consult service at a major tertiary care center for 72 consecutive hours (6 consecutive shifts). We collected minute-by-minute data using predefined work-task criteria: direct new patient contact, direct existing patient contact, communications with other providers, documentation/administrative time, transit time, and basic human needs. A seventh category comprised remaining less-productive work was termed as standby. In a 720-minute shift, residents spent on an average: 191 minutes (26.5%) performing documentation/administrative duties, 167.0 minutes (23.2%) in direct contact with new patient consults, 129.6 minutes (17.1%) in communication with other providers regarding patients, 116.2 (16.1%) minutes in standby, 63.7 minutes (8.8%) in transit, 32.6 minutes (4.5%) with existing patients, and 20 minutes (2.7%) attending to basic human needs. Residents performed an additional 130 minutes of administrative work off duty. Secondary analysis revealed residents were more likely to perform administrative work rather than directly interact with existing patients (p = 0.006) or attend to basic human needs (p = 0.003). Orthopedic surgery residents spend a large proportion of their time performing documentation/administrative-type work and their workday can be operationally optimized to minimize nonvalue-adding tasks. Formal workflow analysis may aid program directors in systematic process improvements to better align

Burnout syndrome during residency in internal medicine and pediatrics in a country without working time directive.

Science.gov (United States)

Aksoy, Duygu Yazgan; Durusu Tanriover, Mine; Unal, Sule; Dizdar, Omer; Kalyoncu, Umut; Karakaya, Jale; Unal, Serhat; Kale, Gulsev

2014-01-01

The purpose of this paper is to demonstrate burnout syndrome among internal medicine and pediatrics residents in a country that does not have the working time directive (WTD) and also to determine the risk factors and consequent impact on efficient functioning in clinical areas. A 57-item questionnaire was given to internal medicine and pediatrics residents. Responses from 22 pediatrics and 33 internal medicine residents were evaluated. Demographic findings, burnout scores, having hobbies, social activities and reading books unrelated to medicine were similar between the two groups. Six pediatrics residents (27.3 per cent) and 11 (33.3 per cent) internal medicine residents met the criteria for clinically significant burnout. Personal accomplishment scores and reading books unrelated to medicine were found to be related to burnout. Burnout is a syndrome characterized by depersonalization, emotional exhaustion and a low sense of personal accomplishment. It is important to document burnout in countries where WTDs are not implemented. Further studies might demonstrate burnout's effect on patient safety, service quality and physician's performance.

RTDB: A memory resident real-time object database

International Nuclear Information System (INIS)

Nogiec, Jerzy M.; Desavouret, Eugene

2003-01-01

RTDB is a fast, memory-resident object database with built-in support for distribution. It constitutes an attractive alternative for architecting real-time solutions with multiple, possibly distributed, processes or agents sharing data. RTDB offers both direct and navigational access to stored objects, with local and remote random access by object identifiers, and immediate direct access via object indices. The database supports transparent access to objects stored in multiple collaborating dispersed databases and includes a built-in cache mechanism that allows for keeping local copies of remote objects, with specifiable invalidation deadlines. Additional features of RTDB include a trigger mechanism on objects that allows for issuing events or activating handlers when objects are accessed or modified and a very fast, attribute based search/query mechanism. The overall architecture and application of RTDB in a control and monitoring system is presented

Tritium activity concentrations and residence times of groundwater collected in Rokkasho, Japan.

Science.gov (United States)

Hasegawa, Hidenao; Ueda, Shinji; Akata, Naofumi; Kakiuchi, Hideki; Hisamatsu, Shun'ichi

2015-11-01

Tritium ((3)H) concentrations were measured in groundwater samples from four surface wells (4-10 m deep), four shallow wells (24-26.5 m deep) and a 150-m-deep well in the Futamata River catchment area, which is adjacent to the large-scale commercial spent nuclear fuel reprocessing plant in Rokkasho, Japan. The (3)H concentrations in most of the surface- and shallow-well samples (<0.03-0.57 Bq l(-1)) were similar to those in precipitation (annual mean: 0.31-0.79 Bq l(-1)), suggesting that the residence time of the water in those wells was 0-15 y. The (3)H concentrations in the samples from a 26-m-deep well and the 150-m-deep well were lower than those in the other wells, indicating that groundwater with a long residence time exists in deep aquifers and the estuary area of the catchment. It is not clear whether (3)H released during test operation of the plant with actual spent nuclear fuel affected the (3)H concentrations observed in this study. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Integrated models for solid waste management in tourism regions: Langkawi Island, Malaysia.

Science.gov (United States)

Shamshiry, Elmira; Nadi, Behzad; Mokhtar, Mazlin Bin; Komoo, Ibrahim; Hashim, Halimaton Saadiah; Yahaya, Nadzri

2011-01-01

The population growth, changing consumption patterns, and rapid urbanization contribute significantly to the growing volumes of solid waste that are generated in urban settings. As the rate of urbanization increases, demand on the services of solid waste management increases. The rapid urban growth in Langkawi Island, Malaysia, combined with the increasing rates of solid waste production has provided evidence that the traditional solid waste management practices, particularly the methods of waste collection and disposal, are inefficient and quite nonsustainable. Accordingly, municipal managers and planners in Langkawi need to look for and adopt a model for solid waste management that emphasizes an efficient and sustainable management of solid wastes in Langkawi Island. This study presents the current practices of solid waste management in Langkawi Island, describes the composition of the solid waste generated in that area, and presents views of local residents and tourist on issues related to solid waste management like the aesthetic value of the island environment. The most important issue of this paper is that it is the first time that integrated solid waste management is investigated in the Langkawi Island.

Leveraging time and learning style, iPod vs. realtime attendance at a series of medicine residents conferences: a randomised controlled trial

Directory of Open Access Journals (Sweden)

Michael Tempelhof

2009-06-01

Conclusions Residency training programmes can optimise time management strategies with the integration of innovative learning resources into educational curricula. This study suggests that iPod capture of conferences is a reasonable resource to help meet the educational goals of residents and residency programs.

Residents as teachers: psychiatry and family medicine residents' self-assessment of teaching knowledge, skills, and attitudes.

Science.gov (United States)

Brand, Michael W; Ekambaram, Vijayabharathi; Tucker, Phebe; Aggarwal, Ruchi

2013-09-01

Residents are one of the prime sources of information and education for medical students. As an initial step in supporting residents as teachers, a baseline self-assessment of residents' knowledge, skills, attitudes, and values related to teaching was conducted among psychiatry and family medicine residents to compare and improve their confidence and skills as teachers. Psychiatry residents (N=12) and family medicine residents (N=23) completed self-assessments of their knowledge, skills, attitudes, and values related to teaching. Residents also were asked to list steps used in the One-Minute Preceptor process and estimate the time each spent in teaching. Descriptive summary statistics were used for four main areas related to teaching; t-test and chi-square analyses were conducted to ascertain whether there was a significant difference in resident groups. In the current study, the perceived amount of time spent for teaching patients was significantly higher among family practice residents, whereas no group differences were found for time teaching medical students, peers, community members, non-physicians, or others. However, family medicine residents rated themselves higher than psychiatry residents in their understanding of their roles in teaching medical students and teaching patients. Also, family medicine residents' self-reported teaching skills were more advanced (82.4%) than psychiatry residents' (54.2%). They most likely applied at least two different teaching methods in inpatient and outpatient settings, as compared with psychiatry residents. No significant group differences were found in the other 15 items assessing teaching knowledge, skills, attitudes, and values. Results indicate that residents' knowledge, skills, attitudes, and values regarding teaching varies across institutions and training programs. The psychiatry residents in this study do not clearly understand their role as educators with patients and medical students; they have a less clear

Life events during surgical residency have different effects on women and men over time.

Science.gov (United States)

Chen, Michelle M; Yeo, Heather L; Roman, Sanziana A; Bell, Richard H; Sosa, Julie A

2013-08-01

Women represent half of medical school graduates in the United States. Our aim was to characterize the effects of marriage and childbirth on the experiences of surgery residents. This was a prospective, longitudinal study of categorical general surgery residents between 2008 and 2010. Outcomes included changes in faculty and peer relationships, work-life balance, financial security, and career goals over time. We included 4,028 residents. Compared with men, women in postgraduate years (PGYs) 1 through 5 were less likely to be married (28.2% to 47.3% vs 49.6% to 67.6%) or have children (4.6% to 18.0% vs 19.0% to 45.8%) (P < .001). Women who married during PGY1 to PGY3 became worried about performing in front of senior residents (P = .005); men who married were more likely to be happy at work (P = .005). Women who had a first child during PGY1 to PGY3 were more likely to feel overwhelmed (P = .008) and worry about financial security (P = .03) than other women. Men who had a child were more likely to feel supported by faculty (P = .004), but they experienced more family strain (P = .008) compared to childless men. Marriage and childbirth are associated with divergent changes in career experiences for women and men. Women lag behind their male peers in these life events from start to finish of residency. Copyright © 2013 Mosby, Inc. All rights reserved.

Leadership Book Club: An Innovative Strategy to Incorporate Leadership Development Into Pharmacy Residency Programs.

Science.gov (United States)

Chappell, Alyssa; Dervay, Katelyn

2016-09-01

Purpose: To describe an innovative strategy for incorporating leadership training and development across multiple postgraduate year 2 (PGY2) pharmacy residency programs at a single institution. Background: Tampa General Hospital has 7 pharmacy residency positions: 4 postgraduate year 1 (PGY1) residents and a single resident for each of the 3 PGY2 programs (critical care, emergency medicine, and solid organ transplant). Administrative topics are incorporated across the PGY1 and PGY2 residency programs, with each PGY2 program having additional administrative topics specific to their specialty area. Summary: What began as an elective administrative topic discussion for the PGY2 emergency medicine resident has evolved over time into a longitudinal leadership book club. The leadership book club is utilized to meet the residency goals and objectives related to leadership development for all 3 PGY2 programs. Each year a single book is identified through the American Society of Health-System Pharmacists (ASHP) Leadership Academy book list or by participant suggestion. The book is then divided into 4 sections with corresponding hour-long discussions that occur quarterly throughout the residency year. The residency program directors (RPDs) and co-RPDs lead the initial discussion, and each PGY2 resident leads 1 of the subsequent 3 discussions. Based on resident feedback, the leadership book club is an innovative and effective strategy to incorporate leadership training and development into residency training. Conclusion: It is imperative to foster the development of leadership skills in pharmacy residency programs to prevent a future leadership gap in health system pharmacy. Leadership book club is a unique strategy to incorporate leadership training longitudinally across multiple PGY2 residency programs at a single institution.

Effect of fermentation time of mixture of solid and liquid wastes from tapioca industry to percentage reduction of TSS (Total Suspended Solids)

Science.gov (United States)

Pandia, S.; Tanata, S.; Rachel, M.; Octiva, C.; Sialagan, N.

2018-02-01

The waste from tapioca industry is as an organic waste that contains many important compounds such as carbohydrate, protein, and glucose. This research as aimed to know the effect of fermentation time from solid waste combined with waste-water from the tapioca industry to percentage reduction of TSS. The study was started by mixing the solid and liquid wastes from tapioca industry at a ratio of 70:30, 60:40, 50:50, 40:60, and 30:70 (w/w) with a starter from solid waste of cattle in a batch anaerobic digester. The percentage reduction of TSS was 72.2289 at a ratio by weight of the composition of solid and liquid wastes from tapioca industry was 70:30 after 30 days of fermentation time.

Exposure in emergency general surgery in a time-based residency ...

African Journals Online (AJOL)

Objective: This paper aimed to characterize the resident exposure to acute general surgical conditions during a three-months rotation in a general surgical unit. Setting: The Department of Surgery, University of Nairobi and Kenyatta National Referral and Teaching Hospital in Nairobi. MethodS: Four residents (in their first to ...

Combustion of large solid fuels in cement rotary kilns

DEFF Research Database (Denmark)

Nielsen, Anders Rooma

(MBM), waste wood, sewage sludge, paper and plastics. The alternative fuel share of the total energy varies significantly from region to region, but the general trend is towards increased alternative fuel utilization. Solid alternative fuels typically have physical and chemical properties that differ...... from traditional solid fossil fuels. This creates a need for new combustion equipment or modification of existing kiln systems, because alternative fuels may influence process stability and product quality. Process stability is mainly influenced by exposing the raw material bed in the rotary kiln...... oxidation is a slow process which may greatly reduce the amounts of solid fuels to be utilized in the material inlet end of rotary kilns due to the limited residence time. Several parameters control the rate of char oxidation: a) bulk oxygen concentration, b) mass transfer rate of oxygen to char particles...

New residence times of the Holocene reworked shells on the west coast of Bohai Bay, China

Science.gov (United States)

Shang, Zhiwen; Wang, Fu; Li, Jianfen; Marshall, William A.; Chen, Yongsheng; Jiang, Xingyu; Tian, Lizhu; Wang, Hong

2016-01-01

Shelly cheniers and shell-rich beds found intercalated in near-shore marine muds and sandy sediments can be used to indicate the location of ancient shorelines, and help to estimate the height of sea level. However, dating the deposition of material within cheniers and shell-rich beds is not straightforward because much of this material is transported and re-worked, creating an unknown temporal off-set, i.e., the residence time, between the death of a shell and its subsequent entombment. To quantify the residence time during the Holocene on a section of the northern Chinese coastline a total 47 shelly subsamples were taken from 17 discrete layers identified on the west coast of Bohai Bay. This material was AMS 14C dated and the calibrated ages were systematically compared. The subsamples were categorized by type as articulated and disarticulated bivalves, gastropod shells, and undifferentiated shell-hash. It was found that within most individual layers the calibrated ages of the subsamples got younger relative to the amount of apparent post-mortem re-working the material had been subject to. For examples, the 14C ages of the bivalve samples trended younger in this order: shell-hash → split shells → articulated shells. We propose that the younger subsample age determined within an individual layer will be the closest to the actual depositional age of the material dated. Using this approach at four Holocene sites we find residence times which range from 100 to 1260 cal yrs, with two average values of 600 cal yrs for the original 14C dates older than 1 ka cal BP and 100 cal yrs for the original 14C dates younger than 1 ka cal BP, respectively. Using this semi-empirical estimation of the shell residence times we have refined the existing chronology of the Holocene chenier ridges on the west coast of Bohai Bay.

Incorporating resident research into the dermatology residency program

Science.gov (United States)

Wagner, Richard F; Raimer, Sharon S; Kelly, Brent C

2013-01-01

Programmatic changes for the dermatology residency program at The University of Texas Medical Branch were first introduced in 2005, with the faculty goal incorporating formal dermatology research projects into the 3-year postgraduate training period. This curriculum initially developed as a recommendation for voluntary scholarly project activity by residents, but it evolved into a program requirement for all residents in 2009. Departmental support for this activity includes assignment of a faculty mentor with similar interest about the research topic, financial support from the department for needed supplies, materials, and statistical consultation with the Office of Biostatistics for study design and data analysis, a 2-week elective that provides protected time from clinical activities for the purpose of preparing research for publication and submission to a peer-reviewed medical journal, and a departmental award in recognition for the best resident scholarly project each year. Since the inception of this program, five classes have graduated a total of 16 residents. Ten residents submitted their research studies for peer review and published their scholarly projects in seven dermatology journals through the current academic year. These articles included three prospective investigations, three surveys, one article related to dermatology education, one retrospective chart review, one case series, and one article about dermatopathology. An additional article from a 2012 graduate about dermatology education has also been submitted to a journal. This new program for residents was adapted from our historically successful Dermatology Honors Research Program for medical students at The University of Texas Medical Branch. Our experience with this academic initiative to promote dermatology research by residents is outlined. It is recommended that additional residency programs should consider adopting similar research programs to enrich resident education. PMID:23901305

Incorporating resident research into the dermatology residency program.

Science.gov (United States)

Wagner, Richard F; Raimer, Sharon S; Kelly, Brent C

2013-01-01

Programmatic changes for the dermatology residency program at The University of Texas Medical Branch were first introduced in 2005, with the faculty goal incorporating formal dermatology research projects into the 3-year postgraduate training period. This curriculum initially developed as a recommendation for voluntary scholarly project activity by residents, but it evolved into a program requirement for all residents in 2009. Departmental support for this activity includes assignment of a faculty mentor with similar interest about the research topic, financial support from the department for needed supplies, materials, and statistical consultation with the Office of Biostatistics for study design and data analysis, a 2-week elective that provides protected time from clinical activities for the purpose of preparing research for publication and submission to a peer-reviewed medical journal, and a departmental award in recognition for the best resident scholarly project each year. Since the inception of this program, five classes have graduated a total of 16 residents. Ten residents submitted their research studies for peer review and published their scholarly projects in seven dermatology journals through the current academic year. These articles included three prospective investigations, three surveys, one article related to dermatology education, one retrospective chart review, one case series, and one article about dermatopathology. An additional article from a 2012 graduate about dermatology education has also been submitted to a journal. This new program for residents was adapted from our historically successful Dermatology Honors Research Program for medical students at The University of Texas Medical Branch. Our experience with this academic initiative to promote dermatology research by residents is outlined. It is recommended that additional residency programs should consider adopting similar research programs to enrich resident education.

Hydraulic residence time and iron removal in a wetland receiving ferruginous mine water over a 4 year period from commissioning.

Science.gov (United States)

Kusin, F M; Jarvis, A P; Gandy, C J

2010-01-01

Analysis of residence time distribution (RTD) has been conducted for the UK Coal Authority's mine water treatment wetland at Lambley, Northumberland, to determine the hydraulic performance of the wetland over a period of approximately 4 years since site commissioning. The wetland RTD was evaluated in accordance with moment analysis and modelled based on a tanks-in-series (TIS) model to yield the hydraulic characteristics of system performance. Greater hydraulic performance was seen during the second site monitoring after 21 months of site operation i.e. longer hydraulic residence time to reflect overall system hydraulic efficiency, compared to wetland performance during its early operation. Further monitoring of residence time during the third year of wetland operation indicated a slight reduction in hydraulic residence time, thus a lower system hydraulic efficiency. In contrast, performance during the fourth year of wetland operation exhibited an improved overall system hydraulic efficiency, suggesting the influence of reed growth over the lifetime of such systems on hydraulic performance. Interestingly, the same pattern was found for iron (which is the primary pollutant of concern in ferruginous mine waters) removal efficiency of the wetland system from the second to fourth year of wetland operation. This may therefore, reflect the maturity of reeds for maintaining efficient flow distribution across the wetland to retain a longer residence time and significant fractions of water involved to enhance the extent of treatment received for iron attenuation. Further monitoring will be conducted to establish whether such performance is maintained, or whether efficiency decreases over time due to accumulation of dead plant material within the wetland cells.

High speed real-time wavefront processing system for a solid-state laser system

Science.gov (United States)

Liu, Yuan; Yang, Ping; Chen, Shanqiu; Ma, Lifang; Xu, Bing

2008-03-01

A high speed real-time wavefront processing system for a solid-state laser beam cleanup system has been built. This system consists of a core2 Industrial PC (IPC) using Linux and real-time Linux (RT-Linux) operation system (OS), a PCI image grabber, a D/A card. More often than not, the phase aberrations of the output beam from solid-state lasers vary fast with intracavity thermal effects and environmental influence. To compensate the phase aberrations of solid-state lasers successfully, a high speed real-time wavefront processing system is presented. Compared to former systems, this system can improve the speed efficiently. In the new system, the acquisition of image data, the output of control voltage data and the implementation of reconstructor control algorithm are treated as real-time tasks in kernel-space, the display of wavefront information and man-machine conversation are treated as non real-time tasks in user-space. The parallel processing of real-time tasks in Symmetric Multi Processors (SMP) mode is the main strategy of improving the speed. In this paper, the performance and efficiency of this wavefront processing system are analyzed. The opened-loop experimental results show that the sampling frequency of this system is up to 3300Hz, and this system can well deal with phase aberrations from solid-state lasers.

Residence Times in Central Valley Aquifers Recharged by Dammed Rivers

Science.gov (United States)

Loustale, M.; Paukert Vankeuren, A. N.; Visser, A.

2017-12-01

Groundwater is a vital resource for California, providing between 30-60% of the state's water supply. Recent emphasis on groundwater sustainability has induced a push to characterize recharge rates and residence times for high priority aquifers, including most aquifers in California's Central Valley. Flows in almost all rivers from the western Sierra to the Central Valley are controlled by dams, altering natural flow patterns and recharge to local aquifers. In eastern Sacramento, unconfined and confined shallow aquifers (depth recharged by a losing reach of the Lower American River, despite the presence of levees with slurry cut-off walls.1 Flow in the Lower American River is controlled through the operation of the Folsom and Nimbus Dams, with a minimum flow of 500 cfs. Water table elevation in wells in close proximity to the river are compared to river stage to determine the effect of river stage on groundwater recharge rates. Additionally, Tritium-3Helium dates and stable isotopes (∂18O and ∂2H) have been measured in monitoring wells 200- 2400 ft lateral distance from the river, and depths of 25 -225 feet BGS. Variation in groundwater age in the vertical and horizontal directions are used to determine groundwater flow path and velocity. These data are then used to calculate residence time of groundwater in the unconfined and confined aquifer systems for the Central Valley in eastern Sacramento. Applying groundwater age tracers can benefit future compliance metrics of the California Sustainable Groundwater Resources Act (SGMA), by quantifying river seepage rates and impacts of groundwater management on surface water resources. 1Moran et al., UCRL-TR-203258, 2004.

Redfield Ratios in Inland Waters: Higher Biological Control of C:N:P Ratios in Tropical Semi-arid High Water Residence Time Lakes

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Ng H. They

2017-08-01

Full Text Available The canonical Redfield C:N:P ratio for algal biomass is often not achieved in inland waters due to higher C and N content and more variability when compared to the oceans. This has been attributed to much lower residence times and higher contributions of the watershed to the total organic matter pool of continental ecosystems. In this study we examined the effect of water residence times in low latitude lakes (in a gradient from humid to a semi-arid region on seston elemental ratios in different size fractions. We used lake water specific conductivity as a proxy for residence time in a region of Eastern Brazil where there is a strong precipitation gradient. The C:P ratios decreased in the seston and bacterial size-fractions and increased in the dissolved fraction with increasing water retention time, suggesting uptake of N and P from the dissolved pool. Bacterial abundance, production and respiration increased in response to increased residence time and intracellular nutrient availability in agreement with the growth rate hypothesis. Our results reinforce the role of microorganisms in shaping the chemical environment in aquatic systems particularly at long water residence times and highlights the importance of this factor in influencing ecological stoichiometry in all aquatic ecosystems.

The relative importance of water temperature and residence time in predicting cyanobacteria abundance in regulated rivers.

Science.gov (United States)

Cha, YoonKyung; Cho, Kyung Hwa; Lee, Hyuk; Kang, Taegu; Kim, Joon Ha

2017-11-01

Despite a growing awareness of the problems associated with cyanobacterial blooms in rivers, and particularly in regulated rivers, the drivers of bloom formation and abundance in rivers are not well understood. We developed a Bayesian hierarchical model to assess the relative importance of predictors of summer cyanobacteria abundance, and to test whether the relative importance of each predictor varies by site, using monitoring data from 16 sites in the four major rivers of South Korea. The results suggested that temperature and residence time, but not nutrient levels, are important predictors of summer cyanobacteria abundance in rivers. Although the two predictors were of similar significance across the sites, the residence time was marginally better in accounting for the variation in cyanobacteria abundance. The model with spatial hierarchy demonstrated that temperature played a consistently significant role at all sites, and showed no effect from site-specific factors. In contrast, the importance of residence time varied significantly from site to site. This variation was shown to depend on the trophic state, indicated by the chlorophyll-a and total phosphorus levels. Our results also suggested that the magnitude of weir inflow is a key factor determining the cyanobacteria abundance under baseline conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Using 50 years of soil radiocarbon data to identify optimal approaches for estimating soil carbon residence times

Science.gov (United States)

Baisden, W. T.; Canessa, S.

2013-01-01

In 1959, Athol Rafter began a substantial programme of systematically monitoring the flow of 14C produced by atmospheric thermonuclear tests through organic matter in New Zealand soils under stable land use. A database of ∼500 soil radiocarbon measurements spanning 50 years has now been compiled, and is used here to identify optimal approaches for soil C-cycle studies. Our results confirm the potential of 14C to determine residence times, by estimating the amount of ‘bomb 14C’ incorporated. High-resolution time series confirm this approach is appropriate, and emphasise that residence times can be calculated routinely with two or more time points as little as 10 years apart. This approach is generally robust to the key assumptions that can create large errors when single time-point 14C measurements are modelled. The three most critical assumptions relate to: (1) the distribution of turnover times, and particularly the proportion of old C (‘passive fraction’), (2) the lag time between photosynthesis and C entering the modelled pool, (3) changes in the rates of C input. When carrying out approaches using robust assumptions on time-series samples, multiple soil layers can be aggregated using a mixing equation. Where good archived samples are available, AMS measurements can develop useful understanding for calibrating models of the soil C cycle at regional to continental scales with sample numbers on the order of hundreds rather than thousands. Sample preparation laboratories and AMS facilities can play an important role in coordinating the efficient delivery of robust calculated residence times for soil carbon.

Using 50 years of soil radiocarbon data to identify optimal approaches for estimating soil carbon residence times

International Nuclear Information System (INIS)

Baisden, W.T.; Canessa, S.

2013-01-01

In 1959, Athol Rafter began a substantial programme of systematically monitoring the flow of 14 C produced by atmospheric thermonuclear tests through organic matter in New Zealand soils under stable land use. A database of ∼500 soil radiocarbon measurements spanning 50 years has now been compiled, and is used here to identify optimal approaches for soil C-cycle studies. Our results confirm the potential of 14 C to determine residence times, by estimating the amount of ‘bomb 14 C’ incorporated. High-resolution time series confirm this approach is appropriate, and emphasise that residence times can be calculated routinely with two or more time points as little as 10 years apart. This approach is generally robust to the key assumptions that can create large errors when single time-point 14 C measurements are modelled. The three most critical assumptions relate to: (1) the distribution of turnover times, and particularly the proportion of old C (‘passive fraction’), (2) the lag time between photosynthesis and C entering the modelled pool, (3) changes in the rates of C input. When carrying out approaches using robust assumptions on time-series samples, multiple soil layers can be aggregated using a mixing equation. Where good archived samples are available, AMS measurements can develop useful understanding for calibrating models of the soil C cycle at regional to continental scales with sample numbers on the order of hundreds rather than thousands. Sample preparation laboratories and AMS facilities can play an important role in coordinating the efficient delivery of robust calculated residence times for soil carbon.

Determination of the hydraulic residence time of trickling filters using radiotracer experiments

International Nuclear Information System (INIS)

Debien, Bruno R.; Ferreira, Ladislau M.; Barreto, Alberto A.; Pinto, Amenonia M.F.

2013-01-01

Trickling filters (TF) are bioreactors fulfilled with inert materials working as support for biofilm development, and have been used in a large scale in wastewater treatment for organic matter, ammonia nitrogen and nitrate removal. TF's can be widely used in Brazil, especially because of its simplicity and operational low cost. The efficiency of pollutants removal processes depends on the water flow dynamics inside the reactor. For this reason, in the present work the mean residence time of two TF's containing different support materials were determined by means of tracer testes. The radioisotope 82Br - a gamma radiation emitter, produced from soluble potassium bromide irradiated in the TRIGA reactor at the Centre for the Development of Nuclear Energy (CDTN) - was used as a pseudo-conservative tracer for the comparative study of aqueous phase flow dynamics in both TF's. Mean residence time for the first TF (containing a single support material) was 0,3 hours, much smaller than the value obtained for the second TF (containing two alternated support materials), around 2 hours. These results were already expected, once the alternated material is denser than the single one, and are very important for numerical modeling studies aiming to determine the kinetic constant for removal of the pollutants cited above. (author)

Determination of the hydraulic residence time of trickling filters using radiotracer experiments

Energy Technology Data Exchange (ETDEWEB)

Debien, Bruno R.; Ferreira, Ladislau M.; Barreto, Alberto A.; Pinto, Amenonia M.F., E-mail: brunordebien@gmail.com [Universidade Federal de Minas Gerais (UFMG), Minas Gerais, MG (Brazil). Dept. de Geografia. Lab. de Geomorfologia; Moreira, Rubens M., E-mail: aab@cdtn.br, E-mail: amfp@cdtn.br, E-mail: rubens@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2013-07-01

Trickling filters (TF) are bioreactors fulfilled with inert materials working as support for biofilm development, and have been used in a large scale in wastewater treatment for organic matter, ammonia nitrogen and nitrate removal. TF's can be widely used in Brazil, especially because of its simplicity and operational low cost. The efficiency of pollutants removal processes depends on the water flow dynamics inside the reactor. For this reason, in the present work the mean residence time of two TF's containing different support materials were determined by means of tracer testes. The radioisotope 82Br - a gamma radiation emitter, produced from soluble potassium bromide irradiated in the TRIGA reactor at the Centre for the Development of Nuclear Energy (CDTN) - was used as a pseudo-conservative tracer for the comparative study of aqueous phase flow dynamics in both TF's. Mean residence time for the first TF (containing a single support material) was 0,3 hours, much smaller than the value obtained for the second TF (containing two alternated support materials), around 2 hours. These results were already expected, once the alternated material is denser than the single one, and are very important for numerical modeling studies aiming to determine the kinetic constant for removal of the pollutants cited above. (author)

Forecasting municipal solid waste generation using prognostic tools and regression analysis.

Science.gov (United States)

Ghinea, Cristina; Drăgoi, Elena Niculina; Comăniţă, Elena-Diana; Gavrilescu, Marius; Câmpean, Teofil; Curteanu, Silvia; Gavrilescu, Maria

2016-11-01

For an adequate planning of waste management systems the accurate forecast of waste generation is an essential step, since various factors can affect waste trends. The application of predictive and prognosis models are useful tools, as reliable support for decision making processes. In this paper some indicators such as: number of residents, population age, urban life expectancy, total municipal solid waste were used as input variables in prognostic models in order to predict the amount of solid waste fractions. We applied Waste Prognostic Tool, regression analysis and time series analysis to forecast municipal solid waste generation and composition by considering the Iasi Romania case study. Regression equations were determined for six solid waste fractions (paper, plastic, metal, glass, biodegradable and other waste). Accuracy Measures were calculated and the results showed that S-curve trend model is the most suitable for municipal solid waste (MSW) prediction. Copyright © 2016 Elsevier Ltd. All rights reserved.

Reflections in a time of transition: orthopaedic faculty and resident understanding of accreditation schemes and opinions on surgical skills feedback

Directory of Open Access Journals (Sweden)

Kenneth R. Gundle

2016-04-01

Full Text Available Introduction: Orthopaedic surgery is one of the first seven specialties that began collecting Milestone data as part of the Accreditation Council for Graduate Medical Education's Next Accreditation System (NAS rollout. This transition from process-based advancement to outcome-based education is an opportunity to assess resident and faculty understanding of changing paradigms, and opinions about technical skill evaluation. Methods: In a large academic orthopaedic surgery residency program, residents and faculty were anonymously surveyed. A total of 31/32 (97% residents and 29/53 (55% faculty responded to Likert scale assessments and provided open-ended responses. An internal end-of-rotation audit was conducted to assess timeliness of evaluations. A mixed-method analysis was utilized, with nonparametric statistical testing and a constant-comparative qualitative method. Results: There was greater familiarity with the six core competencies than with Milestones or the NAS (p<0.05. A majority of faculty and residents felt that end-of-rotation evaluations were not adequate for surgical skills feedback. Fifty-eight per cent of residents reported that end-of-rotation evaluations were rarely or never filled out in a timely fashion. An internal audit demonstrated that more than 30% of evaluations were completed over a month after rotation end. Qualitative analysis included themes of resident desire for more face-to-face feedback on technical skills after operative cases, and several barriers to more frequent feedback. Discussion: The NAS and outcome-based education have arrived. Residents and faculty need to be educated on this changing paradigm. This transition period is also a window of opportunity to address methods of evaluation and feedback. In our orthopaedic residency, trainees were significantly less satisfied than faculty with the amount of technical and surgical skills feedback being provided to trainees. The quantitative and qualitative analyses

Personal Therapy in Psychiatry Residency Training: A National Survey of Canadian Psychiatry Residents.

Science.gov (United States)

Hadjipavlou, George; Halli, Priyanka; Hernandez, Carlos A Sierra; Ogrodniczuk, John S

2016-02-01

The authors collected nationally representative data on Canadian residents' experiences with and perspectives on personal psychotherapy in their psychiatric training. A 43-item questionnaire was distributed electronically to all current psychiatry residents in Canada (N = 839). Four hundred residents from every program across Canada returned the survey (response rate 47.7%). The prevalence of personal therapy at any time was 55.3%, with 42.8% receiving personal therapy during residency. Of residents who undertook personal psychotherapy, 59.3% engaged in weekly therapy, 74.1% received psychodynamic psychotherapy, and 81.5% participated in long-term therapy (>1 year). Personal growth, self-understanding, and professional development were the most common reasons for engaging in personal therapy; however, one-third of residents did so to alleviate symptoms of depression, anxiety, or other mental health concerns. Time was the most important factor impeding residents from personal therapy; only 8.8% found stigma to act as a barrier. The vast majority of residents rated their experience with personal therapy as having a positive or very positive impact on their personal life (84.8%) and overall development as psychiatrists (81.8%). For 64% of respondents, personal therapy had an important or very important role in psychiatry residency training. Residents who received personal therapy rated themselves as better able to understand what happens moment by moment during therapy sessions, detect and deal with patients' emotional reactions, and constructively use their personal reactions to patients. Interest in personal therapy remains strong among psychiatry trainees in Canada. Residents who engaged in psychotherapy endorsed greater confidence in psychotherapy and rated their psychotherapy skills more favorably than those who had never been in the patient role, supporting the view of personal therapy as an important adjunct to psychotherapy training during residency.

Survey of some natural decay-series isotopes in the Wairakei geothermal area and possible residence-time applications

International Nuclear Information System (INIS)

Stewart, M.K.; Burnett, W.C.; Whitehead, N.E.

1993-01-01

Concentrations of selected isotopes in the uranium decay series were determined for samples collected from the Wairakei, Broadlands/Ohaaki and Waiotapu areas. /sup 226/Ra concentrations were found to be low (0.05-0.22 dpm/l), similar to values reported in neutral hot springs at Tatun geothermal area, Taiwan, but lower than other geothermal systems (Yellowstone, USA, and Latera, Central Italy) (up to 25 dpm/l). The potential of /sup 226/Ra//sup 228/Ra ratios for indicating water residence times could not be explored because /sup 228/Ra data was not available. /sup 222/Rn concentrations are higher and related to steam fractions and CO/sub 2/ concentrations. The short half-life (3.8 days) makes /sup 222/Rn suitable for estimating residence times of radon in steam, and therefore the distance of travel of steam from its source (e.g., wells WK9 and 52). /sup 210/Pb and /sup 210/Po concentrations were very low and less than detection limits in many of the Wairakei waters; no residence time applications are apparent for these isotopes. (author). 11 refs.; 5 figs.; 3 tabs

Psychotherapy Training: Residents' Perceptions and Experiences.

Science.gov (United States)

Kovach, Jessica G; Dubin, William R; Combs, Christopher J

2015-10-01

This survey examined actual training hours in psychotherapy modalities as reported by residents, residents' perceptions of training needs, and residents' perceptions of the importance of different aspects of psychotherapy training. A brief, voluntary, anonymous, Internet-based survey was developed. All 14 program directors for Accreditation Council for Graduate Medical Education accredited programs in Pennsylvania, New Jersey, and Delaware provided email addresses for current categorical residents. The survey inquired about hours of time spent in various aspects of training, value assigned to aspects of training, residents' involvement in their own psychotherapy, and overall resident wellness. The survey was e-mailed to 328 residents. Of the 328 residents contacted, 133 (40.5%) responded. Median reported number of PGY 3 and 4 performed versus perceived ideal hours of supportive therapy, cognitive behavioral therapy (CBT), and psychodynamic therapy did not differ. Answers for clinical time utilizing these modalities ranged from "none or less than 1 h" per month to 20+ h per month. PGY 3 and 4 residents reported a median of "none or less than 1 h" per month performed of interpersonal, dialectical behavior therapy, couples/family/group, and child therapies but preferred more time using these therapies. Residents in all years of training preferred more hours of didactic instruction for all psychotherapies and for medication management. Residents ranked teaching modalities in the following order of importance: supervision, hours of psychotherapy performed, personal psychotherapy, readings, and didactic instruction. Residents engaged in their own psychotherapy were significantly more likely to rank the experiential aspects of psychotherapy training (personal psychotherapy, supervision, and hours performed) higher than residents not in psychotherapy. Current psychotherapy training for psychiatry residents is highly variable, but overall, residents want more

Using stable isotope tracers to assess hydrological flow paths, residence times and landscape influences in a nested mesoscale catchment

Directory of Open Access Journals (Sweden)

P. Rodgers

2005-01-01

Full Text Available δ18O measurements in precipitation and stream waters were used to investigate hydrological flow paths and residence times at nested spatial scales in the mesoscale (233 km2 River Feugh catchment in the northeast of Scotland over the 2001-2002 hydrological year. Precipitation δ18O exhibited strong seasonal variation, which although significantly damped within the catchment, was reflected in stream water at six sampling sites. This allowed δ18O variations to be used to infer the relative influence of soil-derived storm flows with a seasonally variable isotopic signature, and groundwater of apparently more constant isotopic composition. Periodic regression analysis was then used to examine the sub-catchment difference using an exponential flow model to provide indicative estimates of mean stream water residence times, which varied between approximately 3 and 14 months. This showed that the effects of increasing scale on estimated mean stream water residence time was minimal beyond that of the smallest (ca. 1 km2 headwater catchment scale. Instead, the interaction of catchment soil cover and topography appeared to be the dominant controlling influence. Where sub-catchments had extensive peat coverage, responsive hydrological pathways produced seasonally variable δ18O signatures in runoff with short mean residence times (ca. 3 months. In contrast, areas dominated by steeper slopes, more freely draining soils and larger groundwater storage in shallow valley-bottom aquifers, deeper flow paths allow for more effective mixing and damping of δ18O indicating longer residence times (>12 months. These insights from δ18O measurements extend the hydrological understanding of the Feugh catchment gained from previous geochemical tracer studies, and demonstrate the utility of isotope tracers in investigating the interaction of hydrological processes and catchment characteristics at larger spatial scales.

Integrated Models for Solid Waste Management in Tourism Regions: Langkawi Island, Malaysia

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Elmira Shamshiry

2011-01-01

Full Text Available The population growth, changing consumption patterns, and rapid urbanization contribute significantly to the growing volumes of solid waste that are generated in urban settings. As the rate of urbanization increases, demand on the services of solid waste management increases. The rapid urban growth in Langkawi Island, Malaysia, combined with the increasing rates of solid waste production has provided evidence that the traditional solid waste management practices, particularly the methods of waste collection and disposal, are inefficient and quite nonsustainable. Accordingly, municipal managers and planners in Langkawi need to look for and adopt a model for solid waste management that emphasizes an efficient and sustainable management of solid wastes in Langkawi Island. This study presents the current practices of solid waste management in Langkawi Island, describes the composition of the solid waste generated in that area, and presents views of local residents and tourist on issues related to solid waste management like the aesthetic value of the island environment. The most important issue of this paper is that it is the first time that integrated solid waste management is investigated in the Langkawi Island.

Integrated Models for Solid Waste Management in Tourism Regions: Langkawi Island, Malaysia

Science.gov (United States)

Shamshiry, Elmira; Nadi, Behzad; Bin Mokhtar, Mazlin; Komoo, Ibrahim; Saadiah Hashim, Halimaton; Yahaya, Nadzri

2011-01-01

The population growth, changing consumption patterns, and rapid urbanization contribute significantly to the growing volumes of solid waste that are generated in urban settings. As the rate of urbanization increases, demand on the services of solid waste management increases. The rapid urban growth in Langkawi Island, Malaysia, combined with the increasing rates of solid waste production has provided evidence that the traditional solid waste management practices, particularly the methods of waste collection and disposal, are inefficient and quite nonsustainable. Accordingly, municipal managers and planners in Langkawi need to look for and adopt a model for solid waste management that emphasizes an efficient and sustainable management of solid wastes in Langkawi Island. This study presents the current practices of solid waste management in Langkawi Island, describes the composition of the solid waste generated in that area, and presents views of local residents and tourist on issues related to solid waste management like the aesthetic value of the island environment. The most important issue of this paper is that it is the first time that integrated solid waste management is investigated in the Langkawi Island. PMID:21904559

Using 50 years of soil radiocarbon data to identify optimal approaches for estimating soil carbon residence times

Energy Technology Data Exchange (ETDEWEB)

Baisden, W.T., E-mail: t.baisden@gns.cri.nz [National Isotope Centre, GNS Science, P.O. Box 31312, Lower Hutt (New Zealand); Canessa, S. [National Isotope Centre, GNS Science, P.O. Box 31312, Lower Hutt (New Zealand)

2013-01-15

In 1959, Athol Rafter began a substantial programme of systematically monitoring the flow of {sup 14}C produced by atmospheric thermonuclear tests through organic matter in New Zealand soils under stable land use. A database of {approx}500 soil radiocarbon measurements spanning 50 years has now been compiled, and is used here to identify optimal approaches for soil C-cycle studies. Our results confirm the potential of {sup 14}C to determine residence times, by estimating the amount of 'bomb {sup 14}C' incorporated. High-resolution time series confirm this approach is appropriate, and emphasise that residence times can be calculated routinely with two or more time points as little as 10 years apart. This approach is generally robust to the key assumptions that can create large errors when single time-point {sup 14}C measurements are modelled. The three most critical assumptions relate to: (1) the distribution of turnover times, and particularly the proportion of old C ('passive fraction'), (2) the lag time between photosynthesis and C entering the modelled pool, (3) changes in the rates of C input. When carrying out approaches using robust assumptions on time-series samples, multiple soil layers can be aggregated using a mixing equation. Where good archived samples are available, AMS measurements can develop useful understanding for calibrating models of the soil C cycle at regional to continental scales with sample numbers on the order of hundreds rather than thousands. Sample preparation laboratories and AMS facilities can play an important role in coordinating the efficient delivery of robust calculated residence times for soil carbon.

Implementation and evaluation of a simulation curriculum for paediatric residency programs including just-in-time in situ mock codes.

Science.gov (United States)

Sam, Jonathan; Pierse, Michael; Al-Qahtani, Abdullah; Cheng, Adam

2012-02-01

To develop, implement and evaluate a simulation-based acute care curriculum in a paediatric residency program using an integrated and longitudinal approach. Curriculum framework consisting of three modular, year-specific courses and longitudinal just-in-time, in situ mock codes. Paediatric residency program at BC Children's Hospital, Vancouver, British Columbia. The three year-specific courses focused on the critical first 5 min, complex medical management and crisis resource management, respectively. The just-in-time in situ mock codes simulated the acute deterioration of an existing ward patient, prepared the actual multidisciplinary code team, and primed the surrounding crisis support systems. Each curriculum component was evaluated with surveys using a five-point Likert scale. A total of 40 resident surveys were completed after each of the modular courses, and an additional 28 surveys were completed for the overall simulation curriculum. The highest Likert scores were for hands-on skill stations, immersive simulation environment and crisis resource management teaching. Survey results also suggested that just-in-time mock codes were realistic, reinforced learning, and prepared ward teams for patient deterioration. A simulation-based acute care curriculum was successfully integrated into a paediatric residency program. It provides a model for integrating simulation-based learning into other training programs, as well as a model for any hospital that wishes to improve paediatric resuscitation outcomes using just-in-time in situ mock codes.

Maintaining social cohesion is a more important determinant of patch residence time than maximizing food intake rate in a group-living primate, Japanese macaque (Macaca fuscata).

Science.gov (United States)

Kazahari, Nobuko

2014-04-01

Animals have been assumed to employ an optimal foraging strategy (e.g., rate-maximizing strategy). In patchy food environments, intake rate within patches is positively correlated with patch quality, and declines as patches are depleted through consumption. This causes patch-leaving and determines patch residence time. In group-foraging situations, patch residence times are also affected by patch sharing. Optimal patch models for groups predict that patch residence times decrease as the number of co-feeding animals increases because of accelerated patch depletion. However, group members often depart patches without patch depletion, and their patch residence time deviates from patch models. It has been pointed out that patch residence time is also influenced by maintaining social proximity with others among group-living animals. In this study, the effects of maintaining social cohesion and that of rate-maximizing strategy on patch residence time were examined in Japanese macaques (Macaca fuscata). I hypothesized that foragers give up patches to remain in the proximity of their troop members. On the other hand, foragers may stay for a relatively long period when they do not have to abandon patches to follow the troop. In this study, intake rate and foraging effort (i.e., movement) did not change during patch residency. Macaques maintained their intake rate with only a little foraging effort. Therefore, the patches were assumed to be undepleted during patch residency. Further, patch residence time was affected by patch-leaving to maintain social proximity, but not by the intake rate. Macaques tended to stay in patches for short periods when they needed to give up patches for social proximity, and remained for long periods when they did not need to leave to keep social proximity. Patch-leaving and patch residence time that prioritize the maintenance of social cohesion may be a behavioral pattern in group-living primates.

Water Residence Time estimation by 1D deconvolution in the form of a l2 -regularized inverse problem with smoothness, positivity and causality constraints

Science.gov (United States)

Meresescu, Alina G.; Kowalski, Matthieu; Schmidt, Frédéric; Landais, François

2018-06-01

The Water Residence Time distribution is the equivalent of the impulse response of a linear system allowing the propagation of water through a medium, e.g. the propagation of rain water from the top of the mountain towards the aquifers. We consider the output aquifer levels as the convolution between the input rain levels and the Water Residence Time, starting with an initial aquifer base level. The estimation of Water Residence Time is important for a better understanding of hydro-bio-geochemical processes and mixing properties of wetlands used as filters in ecological applications, as well as protecting fresh water sources for wells from pollutants. Common methods of estimating the Water Residence Time focus on cross-correlation, parameter fitting and non-parametric deconvolution methods. Here we propose a 1D full-deconvolution, regularized, non-parametric inverse problem algorithm that enforces smoothness and uses constraints of causality and positivity to estimate the Water Residence Time curve. Compared to Bayesian non-parametric deconvolution approaches, it has a fast runtime per test case; compared to the popular and fast cross-correlation method, it produces a more precise Water Residence Time curve even in the case of noisy measurements. The algorithm needs only one regularization parameter to balance between smoothness of the Water Residence Time and accuracy of the reconstruction. We propose an approach on how to automatically find a suitable value of the regularization parameter from the input data only. Tests on real data illustrate the potential of this method to analyze hydrological datasets.

Reproductive Psychiatry Residency Training: A Survey of Psychiatric Residency Program Directors.

Science.gov (United States)

Osborne, Lauren M; MacLean, Joanna V; Barzilay, Erin Murphy; Meltzer-Brody, Samantha; Miller, Laura; Yang, Sarah Nagle

2018-04-01

The reproductive life cycle has unique influences on the phenotypic expression of mental illness in women. Didactic and clinical training focused on these sex-specific influences should be a vital component of the education of future psychiatrists. The authors sought to determine the current state of and attitudes toward reproductive psychiatry in resident education. The authors administered a web-based survey to psychiatry residency training directors. They assessed the availability of both mandated and optional didactic and clinical training experiences in reproductive psychiatry. Fifty residency program directors answered the survey, for a response rate of 28%. More than half of residency program directors (59%) reported requiring some training in reproductive psychiatry. Both the breadth and depth of topics covered varied greatly among programs. Lack of time (48%) and lack of qualified faculty (26%) were the most frequently cited barriers to more training. Only 40% of residency directors surveyed agreed that all residents should be competent in reproductive psychiatry. These findings suggest that specific training in reproductive psychiatry is inconsistent in US residency programs, and that training that does exist varies considerably in clinical time and content. Given that women comprise more than 50% of all psychiatric patients and most women will menstruate, give birth, and undergo menopause, future psychiatrists would benefit from more systematic instruction in this area. The authors propose the development of a national, standardized reproductive psychiatry curriculum to address this gap and aid in producing psychiatrists competent to treat women at all stages of life.

Radiotracer method for residence time distribution study in multiphase flow system

International Nuclear Information System (INIS)

Sugiharto, S.; Su'ud, Z.; Kurniadi, R.; Wibisono, W.; Abidin, Z.

2009-01-01

[ 131 I] isotope in different chemical compounds have been injected into 24 in hydrocarbon transmission pipeline containing approximately 95% water, 3% crude oil, 2% gas and negligible solid material, respectively. The system is operated at the temperature around 70 deg. C enabling fluids flow is easier in the pipeline. The segment of measurement was chosen far from the junction point of the pipeline, therefore, it was reasonably to assume that the fluids in such multiphase system were separated distinctively. Expandable tubing of injector was used to ensure that the isotopes were injected at the proper place in the sense that [ 131 I]Na isotope was injected into water layer and iodo-benzene, [131] IC 6 H 5, was injected into crude oil regime. The radiotracer selection was based on the compatibility of radiotracer with each of fluids under investigation. [ 131 I]Na was used for measuring flow of water while iodo-benzene, [131] IC 6 H 5, was used for measuring flow of crude oil. Two scintillation detectors were used and they are put at the distances 80 and 100 m, respectively, from injection point. The residence time distribution data were utilized for calculation water and crude oil flows. Several injections were conducted in the experiments. Although the crude oil density is lighter than the density of water, the result of measurement shows that the water flow is faster than the crude oil flow. As the system is water-dominated, water may act as carrier and the movement of crude oil is slowed due to friction between crude oil with water and crude oil with gas at top layer. Above of all, this result was able to give answer on the question why crude oil always arrives behind water as it is checked at gathering station. In addition, the flow patterns of the water in the pipeline calculated by Reynolds number and predicted by simple tank-in-series model is turbulence in character.

Text messaging among residents and faculty in a university general surgery residency program: prevalence, purpose, and patient care.

Science.gov (United States)

Shah, Dhruvil R; Galante, Joseph M; Bold, Richard J; Canter, Robert J; Martinez, Steve R

2013-01-01

There is little information about the use of text messaging (texting) devices among resident and faculty physicians for patient-related care (PRC). To determine the prevalence, frequency, purpose, and concerns regarding texting among resident and attending surgeons and to identify factors associated with PRC texting. E-mail survey. University medical center and its affiliated hospitals. Surgery resident and attending staff. Prevalence, frequency, purpose, and concerns regarding patient-related care text messaging. Overall, 73 (65%) surveyed physicians responded, including 45 resident (66%) and 28 attending surgeons (62%). All respondents owned a texting device. Majority of surgery residents (88%) and attendings (71%) texted residents, whereas only 59% of residents and 65% of attendings texted other faculty. Most resident to resident text occurred at a frequency of 3-5 times/d (43%) compared with most attending to resident texts, which occurred 1-2 times/d (33%). Most resident to attending (25%) and attending to attending (30%) texts occurred 1-2 times/d. Among those that texted, PRC was the most frequently reported purpose for resident to resident (46%), resident to attending (64%), attending to resident (82%), and attending to other attending staff (60%) texting. Texting was the most preferred method to communicate about routine PRC (47% of residents vs 44% of attendings). Age (OR: 0.86, 95% CI: 0.79-0.95; p = 0.003), but not sex, specialty/clinical rotation, academic rank, or postgraduate year (PGY) level predicted PRC texting. Most resident and attending staff surveyed utilize texting, mostly for PRC. Texting was preferred for communicating routine PRC information. Our data may facilitate the development of guidelines for the appropriate use of PRC texting. Copyright © 2013 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Study of solid phase kinetics during cyanidation using the 198 Au radioactive tracer

International Nuclear Information System (INIS)

Barbus, A.; Pop, I.I.; Gaspar, E.

1995-01-01

During cyanidation, the various gold bearing pyrite sorts exhibit different behaviour, that sometimes cause increased cyanidation times influencing the reagent and power consumption, in the same time generating fluctuations in the recovery efficiencies. The introduction of the 198 Au radioactive tracer into the cyanidation circuit enabled us to follow several parameters of the cyanidation kinetics: the average residence time of the gold bearing pyrite in the technological equipment, information about the homogenization process, dispersion of solids and gold dissolution efficiency on each technological stage. (author)

Optimizing residence time, temperature and speed to improve TMP pulp properties and reduce energy

Energy Technology Data Exchange (ETDEWEB)

Sabourin, M.; Xu, E.; Cort, B.; Boileau, I.; Waller, A.

1997-04-01

The concept of reducing energy consumption in pulp mills by increasing the disc speed of refining has been established using single disc and double disc refiners in both pilot plant and mill applications. The RTS study evaluated in this paper reviews the effect of high-speed single disc refining coupled with shortdwell-high pressure retention conditions. Coupling these variables permitted evaluation of an optimum residence time, temperature and speed (RTS) operational window. The objective of the RTS conditions to sufficiently soften the wood chips through high temperature such that the fibre is more receptive to initial defiberization at high intensity. The improved pulp from the primary refiner at high intensity could potentially demonstrate improvements in physical pulp properties at a reduced specific energy requirement. The spruce/fir RTS-TMP described here required significantly less specific energy and produced TMP with slightly improved strength properties and equivalent optical properties compared to conventional TMP pulp. Studies on the radiate pine furnish indicated that the physical pulp property/specific energy relationships could be adjusted by manipulating the residence time. 4 refs., 10 tabs., 10 figs.

Recovery of Sleep or Recovery of Self? A Grounded Theory Study of Residents' Decision Making Regarding How to Spend Their Nonclinical Postcall Time.

Science.gov (United States)

Taylor, Taryn S; Nisker, Jeff; Teunissen, Pim W; Dornan, Tim; Lingard, Lorelei

2016-03-01

As resident work hours policies evolve, residents' off-duty time remains poorly understood. Despite assumptions about how residents should be using their postcall, off-duty time, there is little research on how residents actually use this time and the reasoning underpinning their activities. This study sought to understand residents' nonclinical postcall activities when they leave the hospital, their decision-making processes, and their perspectives on the relationship between these activities and their well-being or recovery. The study took place at a Liaison Committee on Medical Education-accredited Canadian medical school from 2012 to 2014. The authors recruited a purposive and convenience sample of postgraduate year 1-5 residents from six surgical and nonsurgical specialties at three hospitals affiliated with the medical school. Using a constructivist grounded theory approach, semistructured interviews were conducted, audio-taped, transcribed, anonymized, and combined with field notes. The authors analyzed interview transcripts using constant comparative analysis and performed post hoc member checking. Twenty-four residents participated. Residents characterized their predominant approach to postcall decision making as one of making trade-offs between multiple, competing, seemingly incompatible, but equally valuable, activities. Participants exhibited two different trade-off orientations: being oriented toward maintaining a normal life or toward mitigating fatigue. The authors' findings on residents' trade-off orientations suggest a dual recovery model with postcall trade-offs motivated by the recovery of sleep or of self. This model challenges the dominant viewpoint in the current duty hours literature and suggests that the duty hours discussion must be broadened to include other recovery processes.

Residence half-time of {sup 137}Cs in the top-soils of Japanese paddy and upland fields

Energy Technology Data Exchange (ETDEWEB)

Komamura, Misako [National Inst. of Agro-Environmental Sciences, Tsukuba, Ibaraki (Japan); Tsumura, Akito; Kodaira, Kiyoshi

1999-03-01

A series of top-soil samples of 14 paddy fields and 10 upland fields in Japan, were annually collected during more than 30 years, to be examined in the contents of {sup 137}Cs. The data, which were obtained by the use of a gamma spectrometric system, received some statistical treatments to distinguish the annual decline of {sup 137}Cs contents from deviations. Then the authors calculated `residence half-time of {sup 137}Cs` within top-soil, and `eluviation rate of {sup 137}Cs` from top to the sub-layer of the soil. The following nationwide results were obtained irrespective of paddy or upland field: (1) The `apparent residence half-time` was estimated as 16 - 17 years. This consists of both effects of eluviation and nuclear disintegration. (2) The true residence half-time` was reported as 41 - 42 years. This depends on the eluviation speed of {sup 137}Cs exclusively, because the influence of nuclear disintegration has been compensated. (3) The eluviation rate of {sup 137}Cs from top-soil down to the sub-soil was 1.6 - 1.7% per year. (4) The ratio of distribution of {sup 137}Cs between top-soil and the sub-soil was estimated to be 6:4 as average at the date of 1996. (author)

Perceptions, training experiences, and preferences of surgical residents toward laparoscopic simulation training: a resident survey.

Science.gov (United States)

Shetty, Shohan; Zevin, Boris; Grantcharov, Teodor P; Roberts, Kurt E; Duffy, Andrew J

2014-01-01

Simulation training for surgical residents can shorten learning curves, improve technical skills, and expedite competency. Several studies have shown that skills learned in the simulated environment are transferable to the operating room. Residency programs are trying to incorporate simulation into the resident training curriculum to supplement the hands-on experience gained in the operating room. Despite the availability and proven utility of surgical simulators and simulation laboratories, they are still widely underutilized by surgical trainees. Studies have shown that voluntary use leads to minimal participation in a training curriculum. Although there are several simulation tools, there is no clear evidence of the superiority of one tool over the other in skill acquisition. The purpose of this study was to explore resident perceptions, training experiences, and preferences regarding laparoscopic simulation training. Our goal was to profile resident participation in surgical skills simulation, recognize potential barriers to voluntary simulator use, and identify simulation tools and tasks preferred by residents. Furthermore, this study may help to inform whether mandatory/protected training time, as part of the residents' curriculum is essential to enhance participation in the simulation laboratory. A cross-sectional study on general surgery residents (postgraduate years 1-5) at Yale University School of Medicine and the University of Toronto via an online questionnaire was conducted. Overall, 67 residents completed the survey. The institutional review board approved the methods of the study. Overall, 95.5% of the participants believed that simulation training improved their laparoscopic skills. Most respondents (92.5%) perceived that skills learned during simulation training were transferrable to the operating room. Overall, 56.7% of participants agreed that proficiency in a simulation curriculum should be mandatory before operating room experience. The

Highly efficient indoor air purification using adsorption-enhanced-photocatalysis-based microporous TiO2 at short residence time.

Science.gov (United States)

Lv, Jinze; Zhu, Lizhong

2013-01-01

A short residence time is a key design parameter for the removal of organic pollutants in catalyst-based indoor air purification systems. In this study, we synthesized a series of TiO2 with different micropore volumes and studied their removal efficiency of indoor carbonyl pollutants at a short residence time. Our results indicated that the superior adsorption capability of TiO2 with micropores improved its performance in the photocatalytic degradation of cyclohexanone, while the photocatalytic removal of the pollutant successfully kept porous TiO2 from becoming saturated. When treated with 1 mg m(-3) cyclohexanone at a relatively humidity of 18%, the adsorption amount on microporous TiO2 was 5.4-7.9 times higher than that on P25. Removal efficiency via photocatalysis followed'the same order as the adsorption amount: TiO2-5 > TiO2-20 > TiO2-60 > TiO2-180 > P25. The advantage of microporous TiO2 over P25 became more pronounced when the residence time declined from 0.072 to 0.036 s. Moreover, as the concentration of cyclohexanone deceased from 1000 ppb to 500 ppb, removal efficiency by microporous TiO2 increased more rapidly than P25.

How Entrustment Is Informed by Holistic Judgments Across Time in a Family Medicine Residency Program: An Ethnographic Nonparticipant Observational Study.

Science.gov (United States)

Sagasser, Margaretha H; Fluit, Cornelia R M G; van Weel, Chris; van der Vleuten, Cees P M; Kramer, Anneke W M

2017-06-01

Entrustment has mainly been conceptualized as delegating discrete professional tasks. Because residents provide most of their patient care independently, not all resident performance is visible to supervisors; the entrustment process involves more than granting discrete tasks. This study explored how supervisors made entrustment decisions based on residents' performance in a long-term family medicine training program. A qualitative nonparticipant observational study was conducted in 2014-2015 at competency-based family medicine residency programs in the Netherlands. Seven supervisor-resident pairs participated. During two days, one researcher observed first-year residents' patient encounters, debriefing sessions, and supervisor-resident educational meetings and interviewed them separately afterwards. Data were collected and analyzed using iterative, phenomenological inductive research methodology. The entrustment process developed over three phases. Supervisors based their initial entrustment on prior knowledge about the resident. In the ensuing two weeks, entrustment decisions regarding independent patient care were derived from residents' observed general competencies necessary for a range of health problems (clinical reasoning, decision making, relating to patients); medical knowledge and skills; and supervisors' intuition. Supervisors provided supervision during and after encounters. Once residents performed independently, supervisors kept reevaluating their decisions, informed by residents' overall growth in competencies rather than by adhering to a predefined set of tasks. Supervisors in family medicine residency training took a holistic approach to trust, based on general competencies, knowledge, skills, and intuition. Entrustment started before training and developed over time. Building trust is a mutual process between supervisor and resident, requiring a good working relationship.

Results of the 2003 Association of Residents in Radiation Oncology (ARRO) surveys of residents and chief residents in the United States

International Nuclear Information System (INIS)

Jagsi, Reshma; Buck, David A.; Singh, Anurag K.; Engleman, Mark; Thakkar, Vipul; Frank, Steven J.; Flynn, Daniel

2005-01-01

Purpose: To document demographic characteristics of current residents, career motivations and aspirations, and training program policies and resources. Methods: In 2003, the Association of Residents in Radiation Oncology (ARRO) conducted two nationwide surveys: one of all U.S. radiation oncology residents and one of chief residents. Results: The Chief Residents' Survey was completed by representatives from all 77 programs (response rate, 100%). The Residents' Survey was returned by 229 respondents (response rate, 44%). In each, 32% of respondents were female. The most popular career after residency was private practice (46%), followed by permanent academic practice (28%). Changes that would entice those choosing private practice to consider an academic career included more research experience as a resident (76%), higher likelihood of tenure (69%), lesser time commitment (66%), and higher salary (54%). Although the majority of respondents were satisfied with educational experience overall, a number of programs were reported to provide fewer resources than required. Conclusions: Median program resources and numbers of outliers are documented to allow residents and program directors to assess the relative adequacy of experience in their own programs. Policy-making bodies and individual programs should consider these results when developing interventions to improve educational experiences of residents and to increase retention of radiation oncologists in academic practice

Determination of flow patterns in industrial gold leaching tank by radiotracer residence time distribution measurement

International Nuclear Information System (INIS)

Stegowski, Z.; Furman, L.; Dagadu, Ch.P.K.; Akaho, E.H.K.; Danso, K.A.; Mumuni, I.I.; Adu, P.S; Amoah, Ch.

2010-01-01

The carbon-in-leach (CIL) process is one the most efficient methods of gold recovery from gold bearing ores. The efficiency of the leaching process greatly depends on the flow structure created by mechanical agitation (in some cases air agitation) in the leaching tanks. Residence time distribution (RTD) measurement was conducted in the CIL section of a gold processing plant in order to determine the flow structure in the first tank using the 131 I radioactive tracer. The shape of the experimental data revealed that the flow behaviour in the tank was close to an ideal mixer. Modelling of the experimental data, however, revealed that the tank was not behaving as a single perfect mixer, but consisted of two mixing zones. The flow structure in the tank was best described by the '' perfect mixers with exchange '' model consisting of two mixing zones. The model allowed the determination of flow parameters including the mean residence time, flow rate and volumes of the mixing zones. (authors)

MODELING HOW A HURRICANE BARRIER IN NEW BEDFORD HARBOR, MASSACHUSETTS, AFFECTS THE HYDRODYNAMICS AND RESIDENCE TIMES

Science.gov (United States)

Two-dimensional hydrodynamic and transport models were used to simulate tidal and subtidal circulation, residence times, and the longitudinal distributions of conservative constituents in New Bedford Harbor, Massachusetts, before and after a hurricane barrier was constructed. The...

Medication Refusal: Resident Rights, Administration Dilemma.

Science.gov (United States)

Haskins, Danielle R; Wick, Jeannette Y

2017-12-01

Occasionally, residents actively or passively refuse to take medications. Residents may refuse medication for a number of reasons, including religious beliefs, dietary restrictions, misunderstandings, cognitive impairment, desire to self-harm, or simple inconvenience. This action creates a unique situation for pharmacists and long-term facility staff, especially if patients have dementia. Residents have the legal right to refuse medications, and long-term care facilities need to employ a process to resolve disagreement between the health care team that recommends the medication and the resident who refuses it. In some cases, simple interventions like selecting a different medication or scheduling medications in a different time can address and resolve the resident's objection. If the medical team and the resident cannot resolve their disagreement, often an ethics consultation is helpful. Documenting the resident's refusal to take any or all medications, the health care team's actions and any other outcomes are important. Residents' beliefs may change over time, and the health care team needs to be prepared to revisit the issue as necessary.

Improving residents' handovers through just-in-time training for structured communication.

Science.gov (United States)

Rourke, Liam; Amin, Aditi; Boyington, Curtiss; Ao, Peter; Frolova, Natalia

2016-01-01

In a recent quality assurance project we learned that nearly half of the handovers we examined were characterized as unsatisfactory by our residents, who provided examples in which their anxiety had been piqued and patient care had been affected. These reports substantiated a growing body of literature on the relationship between the quality of handover and the quality of patient care, so we sought to improve the quality and consistency of the in-hosptial handovers undertaken by our internal medicine residents. Senior residents attended morning report for three consecutive month long blocks and evaluated the quality of the handovers using an observational protocol comprised of 16 aspects of effective handover. During the first block, the resident observed a median of eight of the 16 practices occurring across the 46 handovers, and a large amount of variability. At the beginning of the subsequent block we presented a concise introduction to a structured handover procedure (SBARR). The median quality of the subsequent 33 handovers rose to 11, and the variability decreased considerably. In the next block we refined the SBARR orientation to focus on the errors observed in the previous blocks, and the improvement in the quality and variability was sustained. The minor change, which requires few resources to sustain, had a favourable impact on the quality of our residents' in-hospital handovers.

Lyophilized sponges loaded with curcumin solid lipid nanoparticles for buccal delivery: Development and characterization.

Science.gov (United States)

Hazzah, Heba A; Farid, Ragwa M; Nasra, Maha M A; El-Massik, Magda A; Abdallah, Ossama Y

2015-08-15

This study aimed to prepare and evaluate mucoadhesive sponges as dosage forms for delivering solid lipid nanoparticles. For this purpose curcumin (Cur) was formulated as solid nanoparticles (SLN) using Gelucire 50/13, and polaxomer 407. The prepared CurSLN dispersion was thickened with different mucoadhesive polymers. Different concentrations of glycerol, and mannitol of range (0.25-20%), and (0-1%), respectively were also examined. The formed gel was poured into oblong molds and freeze dried to form mucoadhesive sponge to be applied to the buccal mucosa. The prepared sponges were evaluated for their, in-vivo residence time, in-vitro and in-vivo drug release, and hydration capacity. Surface morphology for the different sponges were examined using SEM. TEM was also carried out for sponge fragments previously dispersed into water. Infrared spectroscopy was conducted to investigate interaction between used ingredients. The results showed that the CurSLN loaded HPMC, and Polycarbophil sponges showed 4, and 15 h in-vivo residence time, respectively, providing a considerable amount of curcumin into saliva. The incorporation of glycerol and mannitol at concentration of 1% provided elegant and flexible sponges. The SEM showed that the deposition of CurSLN differed according to the type of polymer used. TEM confirmed the integrity of liberated CurSLN from sponges. IR spectra showed an interaction between HPMC and poloxamer 407, which affected its behavior as a gelling agent. The obtained results provide an efficient approach for delivering solid lipid nanoparticles in a solid dosage form keeping the nanoparticle characters and integrity. Copyright © 2015 Elsevier B.V. All rights reserved.

Confidence, knowledge, and skills at the beginning of residency. A survey of pathology residents.

Science.gov (United States)

Hsieh, Cindy M; Nolan, Norris J

2015-01-01

To document the pathology learning experiences of pathology residents prior to residency and to determine how confident they were in their knowledge and technical skills. An online survey was distributed to all pathology residency program directors in the United States, who were requested to forward the survey link to their residents. Data were obtained on pathology electives, grossing experience, and frozen section experience. Likert scale questions assessed confidence level in knowledge and skills. In total, 201 pathology residents responded (8% of residents in the United States). Prior to starting residency, most respondents had exposure to anatomic pathology through elective rotations. Few respondents had work-related experience. Most did not feel confident in their pathology-related knowledge or skills, and many did not understand what pathology resident duties entail. Respondents gained exposure to pathology primarily through elective rotations, and most felt the elective experience prepared them for pathology residency. However, elective time may be enhanced by providing opportunities for students to increase hands-on experience and understanding of resident duties. Copyright© by the American Society for Clinical Pathology.

Mobile technology in radiology resident education.

Science.gov (United States)

Korbage, Aiham C; Bedi, Harprit S

2012-06-01

The authors hypothesized that ownership of a mobile electronic device would result in more time spent learning radiology. Current trends in radiology residents' studying habits, their use of electronic and printed radiology learning resources, and how much of the funds allotted to them are being used toward printed vs electronic education tools were assessed in this study. A survey study was conducted among radiology residents across the United States from June 13 to July 5, 2011. Program directors listed in the Association of Program Directors in Radiology e-mail list server received an e-mail asking for residents to participate in an online survey. The questionnaire consisted of 12 questions and assessed the type of institution, the levels of training of the respondents, and book funds allocated to residents. It also assessed the residents' study habits, access to portable devices, and use of printed and electronic radiology resources. Radiology residents are adopters of new technologies, with 74% owning smart phones and 37% owning tablet devices. Respondents spend nearly an equal amount of time learning radiology from printed textbooks as they do from electronic resources. Eighty-one percent of respondents believe that they would spend more time learning radiology if provided with tablet devices. There is considerable use of online and electronic resources and mobile devices among the current generation of radiology residents. Benefits, such as more study time, may be obtained by radiology programs that incorporate tablet devices into the education of their residents. Copyright © 2012 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Pediatric dermatology training during residency: a survey of the 2014 graduating residents.

Science.gov (United States)

Akhavan, Alaleh; Murphy-Chutorian, Blair; Friedman, Adam

2015-01-01

Knowledge of pediatric dermatology is considered a core competency of dermatology training and should be expected of all practicing dermatologists. While the numbers of both pediatric dermatology fellowships and board certified pediatric dermatologists in the workforce have increased over the years, recent reports suggest that there is a gap in pediatric dermatology education during dermatology residency. The goal of this study is to assess the current state of pediatric education during residency, as well as the clinical experience, satisfaction and expectations of graduating dermatology residents. A 31-question self-report survey was distributed electronically to 294 third-year dermatology residents with questions pertaining to demographics, didactic education, resident experience in pediatric dermatology training, satisfaction with pediatric training and future plans. One hundred and twenty-three residents responded (41.8% response rate) representing approximately 29.1% of the total number of graduating residents. 69 (56.1%) residents reported academic time specifically devoted to pediatric dermatology, the majority (79.7%) of which was led by pediatric dermatologists. 82% of residents reported dedicated pediatric dermatology clinics at their program. 86.8% of respondents felt that their training in pediatric dermatology will allow them to confidently see pediatric dermatology patients in practice. This survey highlights a promising state of pediatric dermatology training among current graduating dermatology residents. The majority of current graduating dermatology residents are satisfied with their pediatric dermatology education, feel confident treating pediatric patients, and plan to see pediatric patients in clinical practice. © 2015 Wiley Periodicals, Inc.

Pediatric resident perceptions of family-friendly benefits.

Science.gov (United States)

Berkowitz, Carol D; Frintner, Mary Pat; Cull, William L

2010-01-01

The aim of this study was to examine the importance of family-friendly features in residency program selection, benefits offered to and used by residents, and importance of benefits in future job selection. A survey of a random, national sample of 1000 graduating pediatric residents in 2008 was mailed and e-mailed. Survey response rate for graduating resident respondents was 59%. Among the respondents, 76% were women. Thirty-seven percent of men and 32% of women were parents. Residents with children were more likely than residents without children to rate family-friendly characteristics as very important in their residency selection (P maternity leave (88%), paternity leave (59%), individual flexibility with schedule (63%), and lactation rooms (55%), but fewer reported on-site child care (24%), care for ill children (19%), and part-time residency positions (12%). Among residents reporting availability, 77% of women with children used maternity leave and lactation rooms. Few held part-time residency positions (2%), but many expressed interest (23% of women with children). The majority of residents with and without children reported that flexibility with schedule was important in their future job selection. Most women with children (71%) and many women without children (52%) considered part-time work to be very important in their job selection. Family-friendly benefits are important to residents, particularly those with children. The data provides a benchmark for the availability and use of family-friendly features at pediatric training programs. The data also shows that many residents are unaware if benefits are offered, which suggests a need to make available benefits more transparent to residents. Copyright 2010 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

A non-fickian approach to the consequences of dumping solid radioactive wastes in a finite ocean

International Nuclear Information System (INIS)

Sarma, T.P.; D'Souza, R.S.; Sastry, V.N.; Soman, S.D.

1981-01-01

A mathematical model is developed to describe the spatial and temporal distributions of radionuclides released from solid wastes dumped on a sea bed. It takes into account the field tested dependence of horizontal eddy diffusion coefficients by the '4/3 power law' and the geochemical mean residence times of these elements in oceans. Since ocean dimensions cannot be considered infinite except for very short lived nuclides (a few months), the reflections of nuclides at the boundaries and the consequent effects on the overall concentrations have been assessed. The computations indicate that the entire activity is confined to the ocean dimensions, and the integral mean concentration value over the entire depth approaches the well-mixed value at large times. The effect of using the geochemical residence time concept leads to much lower concentration levels in waters for transuranic nuclides such as 239 Pu because of the much shorter geochemical residence times compared to the physical half-lives; in contrast for the majority of the other nuclides, the governing factor is essentially the radioactive decay only. (author)

A Comparison Study of Communication Skills between General Surgery and General Practice Residents on First-time Patient Visits

Directory of Open Access Journals (Sweden)

Ahmed Al Ansari

2012-04-01

Full Text Available Background: There is little published research about differences in doctor-patient communication of different specialties. Accordingly, we compared doctor-patient communication skills in two different specialties, general surgery (GS and general practice (GP. Methods: Twenty residents training at the Bahrain Defence Force Hospital (10 men and 10 women; mean age 28 years; 10 GS and 10 GP participated in 200 patient first visit consultations. The consultations were video-recorded and analysed by four trained observers using the MAAS Global scale. Results: 1 Internal consistency reliability of the MAAS Global (> 0.91 and Ep2 = 0.84 for raters was high, 2 GP residents spent more time (12 minutes than GS residents (7 minutes, in the visits, 3 There were several differences on the MAAS Global items between GP and GS residents (GS > GP, p GS, p < 0.05 on information giving, and 4 The present participants performed well compared to normative samples as well as to criterion-referenced cut-off scores. The general level of communication skills in both specialties, however, was ‘unsatisfactory’ and ‘doubtful’, as it is for normative samples. Conclusion: Excellent doctor-patient communication is essential but does not appear to receive the amount of attention that it deserves in practice settings. There are some differences between specialties as well as unsatisfactory communication skills for both specialties, since residents from both programs spent less time than recommended on each consultation. Our findings emphasize the need to improve the communication skills of physicians in general and for surgeons in particular.

Modelling of slaughterhouse solid waste anaerobic digestion: determination of parameters and continuous reactor simulation.

Science.gov (United States)

López, Iván; Borzacconi, Liliana

2010-10-01

A model based on the work of Angelidaki et al. (1993) was applied to simulate the anaerobic biodegradation of ruminal contents. In this study, two fractions of solids with different biodegradation rates were considered. A first-order kinetic was used for the easily biodegradable fraction and a kinetic expression that is function of the extracellular enzyme concentration was used for the slowly biodegradable fraction. Batch experiments were performed to obtain an accumulated methane curve that was then used to obtain the model parameters. For this determination, a methodology derived from the "multiple-shooting" method was successfully used. Monte Carlo simulations allowed a confidence range to be obtained for each parameter. Simulations of a continuous reactor were performed using the optimal set of model parameters. The final steady-states were determined as functions of the operational conditions (solids load and residence time). The simulations showed that methane flow peaked at a flow rate of 0.5-0.8 Nm(3)/d/m(reactor)(3) at a residence time of 10-20 days. Simulations allow the adequate selection of operating conditions of a continuous reactor. (c) 2010 Elsevier Ltd. All rights reserved.

"It's Not Just Time Off": A Framework for Understanding Factors Promoting Recovery From Burnout Among Internal Medicine Residents.

Science.gov (United States)

Abedini, Nauzley C; Stack, Shobha W; Goodman, Jessie L; Steinberg, Kenneth P

2018-02-01

Burnout rates for internal medicine residents are among the highest of all specialties, yet little is known about how residents recover from burnout. We identified factors promoting recovery from burnout and factors that assist with the subsequent avoidance of burnout among internal medicine residents. A purposive sample of postgraduate year 2 (PGY-2), PGY-3, and recent graduates who experienced and recovered from burnout during residency participated in semistructured, 60-minute interviews from June to August 2016. Using qualitative methods derived from grounded theory, saturation of themes occurred after 25 interviews. Coding was performed in an iterative fashion and consensus was reached on major themes. Coding revealed 2 different categories of resident burnout- circumstantial and existential -with differing recovery and avoidance methods. Circumstantial burnout stemmed from self-limited circumstances and environmental triggers. Recovery from, and subsequent avoidance of, circumstantial burnout arose from (1) resolving workplace challenges; (2) nurturing personal lives; and (3) taking time off. In contrast, existential burnout stemmed from a loss of meaning in medicine and an uncertain professional role. These themes were identified around recovery: (1) recognizing burnout and feeling validated; (2) connecting with patients and colleagues; (3) finding meaning in medicine; and (4) redefining a professional identity and role. Our study suggests that residents experience different types of burnout and have variable methods by which they recover from and avoid further burnout. Categorizing residents' burnout into circumstantial versus existential experiences may serve as a helpful framework for formulating interventions.

Flow and Residence Times of Dynamic River Bank Storage and Sinuosity-Driven Hyporheic Exchange

Science.gov (United States)

Gomez-Velez, J. D.; Wilson, J. L.; Cardenas, M. B.; Harvey, J. W.

2017-10-01

Hydrologic exchange fluxes (HEFs) vary significantly along river corridors due to spatiotemporal changes in discharge and geomorphology. This variability results in the emergence of biogeochemical hot-spots and hot-moments that ultimately control solute and energy transport and ecosystem services from the local to the watershed scales. In this work, we use a reduced-order model to gain mechanistic understanding of river bank storage and sinuosity-driven hyporheic exchange induced by transient river discharge. This is the first time that a systematic analysis of both processes is presented and serves as an initial step to propose parsimonious, physics-based models for better predictions of water quality at the large watershed scale. The effects of channel sinuosity, alluvial valley slope, hydraulic conductivity, and river stage forcing intensity and duration are encapsulated in dimensionless variables that can be easily estimated or constrained. We find that the importance of perturbations in the hyporheic zone's flux, residence times, and geometry is mainly explained by two-dimensionless variables representing the ratio of the hydraulic time constant of the aquifer and the duration of the event (Γd) and the importance of the ambient groundwater flow (Δh∗). Our model additionally shows that even systems with small sensitivity, resulting in small changes in the hyporheic zone extent, are characterized by highly variable exchange fluxes and residence times. These findings highlight the importance of including dynamic changes in hyporheic zones for typical HEF models such as the transient storage model.

Fee-based solid waste collection in economically developing countries: The case of Accra metropolis

Directory of Open Access Journals (Sweden)

Oduro-Appiah, K.

2013-06-01

Full Text Available Fee-based solid waste collection, a system that holds great promise to reducing the financial burden of solid waste management on the municipalities of developing countries is reviewed in this research study. It is to promote financial sustainability through partial or full cost sharing of solid waste collection services and intended to serve as a guide to policy makers and waste management authorities in Ghana and other countries with developing economies. Information through survey and questionnaires from residents across the socio-economic divide was collected to determine willingness and ability to pay for solid waste collection services. A critical assessment of the various capital and operational cost components that come into play in the collection process were considered and computed to determine the economic and social tariff that will be enough to offset the cost of collection, transportation and disposal of solid waste unto landfills. Residents of the metropolis have the ability and are willing to pay an economically affordable user charge of US$1.10 per household per month to offset and remove the financial burden of solid waste collection off the metropolitan assembly. Consistent and efficient collection service is recommended to ensure residents cooperation towards implementation of the system in Ghana.

Groundwater flowpaths and residence times inferred by 14C, 36Cl and 4He isotopes in the Continental Intercalaire aquifer (North-Western Africa)

Science.gov (United States)

Petersen, J. O.; Deschamps, P.; Hamelin, B.; Fourré, E.; Gonçalvès, J.; Zouari, K.; Guendouz, A.; Michelot, J.-L.; Massault, M.; Dapoigny, A.; ASTER Team

2018-05-01

In a semi-arid to arid climate context, dependency on groundwater resources may lead to overexploitation and deterioration of water quality. The Continental Intercalaire (CI) aquifer is one such continental-scale aquifer (more than a million of km2), which is mainly confined, poorly recharged but intensely abstracted. To date, the management of this resource relies on hydrogeological modelling and key parameters such as recharge/discharge rate and groundwater dynamics. We use a combination of residence time indicators (14C, 36Cl, 4He) and stable isotopes of water (2H and 18O) to give greater constraint on the groundwater residence time in the CI. In previous studies, 14C measurements and steady state modelling indicate a residence time of less than 100 ka whereas in others, 36Cl measurements and transient scenarios modelling suggest a longer residence time (>500 ka). In this study, most of the 14C measurements are below the limit of detection, establishing residence times greater than 40 ka and confirming the necessity of strict sampling protocols to exclude all air and AMS measurements when low 14C concentrations are expected. In the Tunisian recharge area, detectable 14C indicate sporadic recharge episodes (3-7 ka and 29-43 ka), whereas 4He and 36Cl concentrations in central areas suggest very old (water quality in the whole system.

Assessment of resident operative performance using a real-time mobile Web system: preparing for the milestone age.

Science.gov (United States)

Wagner, Justin P; Chen, David C; Donahue, Timothy R; Quach, Chi; Hines, O Joe; Hiatt, Jonathan R; Tillou, Areti

2014-01-01

To satisfy trainees' operative competency requirements while improving feedback validity and timeliness using a mobile Web-based platform. The Southern Illinois University Operative Performance Rating Scale (OPRS) was embedded into a website formatted for mobile devices. From March 2013 to February 2014, faculty members were instructed to complete the OPRS form while providing verbal feedback to the operating resident at the conclusion of each procedure. Submitted data were compiled automatically within a secure Web-based spreadsheet. Conventional end-of-rotation performance (CERP) evaluations filed 2006 to 2013 and OPRS performance scores were compared by year of training using serial and independent-samples t tests. The mean CERP scores and OPRS overall resident operative performance scores were directly compared using a linear regression model. OPRS mobile site analytics were reviewed using a Web-based reporting program. Large university-based general surgery residency program. General Surgery faculty used the mobile Web OPRS system to rate resident performance. Residents and the program director reviewed evaluations semiannually. Over the study period, 18 faculty members and 37 residents logged 176 operations using the mobile OPRS system. There were 334 total OPRS website visits. Median time to complete an evaluation was 45 minutes from the end of the operation, and faculty spent an average of 134 seconds on the site to enter 1 assessment. In the 38,506 CERP evaluations reviewed, mean performance scores showed a positive linear trend of 2% change per year of training (p = 0.001). OPRS overall resident operative performance scores showed a significant linear (p = 0.001), quadratic (p = 0.001), and cubic (p = 0.003) trend of change per year of clinical training, reflecting the resident operative experience in our training program. Differences between postgraduate year-1 and postgraduate year-5 overall performance scores were greater with the OPRS (mean = 0.96, CI

The "resident's dilemma"? Values and strategies of medical residents for education interactions: a cellular automata simulation.

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Heckerling, P S; Gerber, B S; Weiner, S J

2006-01-01

Medical residents engage in formal and informal education interactions with fellow residents during the working day, and can choose whether to spend time and effort on such interactions. Time and effort spent on such interactions can bring learning and personal satisfaction to residents, but may also delay completion of clinical work. Using hypothetical cases, we assessed the values and strategies of internal medicine residents at one hospital for both cooperative and non-cooperative education interactions with fellow residents. We then used these data and cellular automata models of two-person games to simulate repeated interactions between residents, and to determine which strategies resulted in greatest accrued value. We conducted sensitivity analyses on several model parameters, to test the robustness of dominant strategies to model assumptions. Twenty-nine of the 57 residents (50.9%) valued cooperation more than non-cooperation no matter what the other resident did during the current interaction. Similarly, thirty-six residents (63.2%) endorsed an unconditional always-cooperate strategy no matter what the other resident had done during their previous interaction. In simulations, an always-cooperate strategy accrued more value (776.42 value units) than an aggregate of strategies containing non-cooperation components (675.0 value units, p = 0.052). Only when the probability of strategy errors reached 50%, or when values were re-ordered to match those of a Prisoner's Dilemma, did non-cooperation-based strategies accrue the most value. Cooperation-based values and strategies were most frequent among our residents, and dominated in simulations of repeated education interactions between them.

Identifying Gaps and Launching Resident Wellness Initiatives: The 2017 Resident Wellness Consensus Summit.

Science.gov (United States)

Zaver, Fareen; Battaglioli, Nicole; Denq, William; Messman, Anne; Chung, Arlene; Lin, Michelle; Liu, Emberlynn L

2018-03-01

Burnout, depression, and suicidality among residents of all specialties have become a critical focus for the medical education community, especially among learners in graduate medical education. In 2017 the Accreditation Council for Graduate Medical Education (ACGME) updated the Common Program Requirements to focus more on resident wellbeing. To address this issue, one working group from the 2017 Resident Wellness Consensus Summit (RWCS) focused on wellness program innovations and initiatives in emergency medicine (EM) residency programs. Over a seven-month period leading up to the RWCS event, the Programmatic Initiatives workgroup convened virtually in the Wellness Think Tank, an online, resident community consisting of 142 residents from 100 EM residencies in North America. A 15-person subgroup (13 residents, two faculty facilitators) met at the RWCS to develop a public, central repository of initiatives for programs, as well as tools to assist programs in identifying gaps in their overarching wellness programs. An online submission form and central database of wellness initiatives were created and accessible to the public. Wellness Think Tank members collected an initial 36 submissions for the database by the time of the RWCS event. Based on general workplace, needs-assessment tools on employee wellbeing and Kern's model for curriculum development, a resident-based needs-assessment survey and an implementation worksheet were created to assist residency programs in wellness program development. The Programmatic Initiatives workgroup from the resident-driven RWCS event created tools to assist EM residency programs in identifying existing initiatives and gaps in their wellness programs to meet the ACGME's expanded focus on resident wellbeing.

Variability in benthic exchange rate, depth, and residence time beneath a shallow coastal estuary

Science.gov (United States)

Russoniello, C. J.; Michael, H. A.; Heiss, J.

2017-12-01

Hydrodynamically-driven exchange of water between the water column and shallow seabed aquifer, benthic exchange, is a significant and dynamic component of coastal and estuarine fluid budgets, but wave-induced benthic exchange has not been measured in the field. Mixing between surface water and groundwater solutes promotes ecologically important chemical reactions, so quantifying benthic exchange rates, depths, and residence times, constrains estimates of coastal chemical cycling. In this study, we present the first field-based direct measurements of wave-induced exchange and compare it to exchange induced by the other primary drivers of exchange - tides, and currents. We deployed instruments in a shallow estuary to measure benthic exchange and temporal variability over an 11-day period. Differential pressure sensors recorded pressure gradients across the seabed, and up-and down-looking ADCPs recorded currents and pressures from which wave parameters, surface-water currents, and water depth were determined. Wave-induced exchange was calculated directly from 1) differential pressure measurements, and indirectly with an analytical solution based on wave parameters from 2) ADCP and 3) weather station data. Groundwater flow models were used to assess the effects of aquifer properties on benthic exchange depth and residence time. Benthic exchange driven by tidal pumping or current-bedform interaction was calculated from tidal stage variation and from ADCP-measured currents at the bed, respectively. Waves were the primary benthic exchange driver (average = 20.0 cm/d, maximum = 92.3 cm/d) during the measurement period. Benthic exchange due to tides (average = 3.7 cm/d) and current-bedform interaction (average = 6.5x10-2 cm/d) was much lower. Wave-induced exchange calculated from pressure measurements and ADCP-measured wave parameters matched well, but wind-based rates underestimated wave energy and exchange. Groundwater models showed that residence time and depth increased

Career Interests of Canadian Psychiatry Residents: What Makes Residents Choose a Research Career?

Science.gov (United States)

Laliberté, Vincent; Rapoport, Mark J.; Andrew, Melissa; Davidson, Marla

2016-01-01

Objectives: Training future clinician-researchers remains a challenge faced by Canadian psychiatry departments. Our objectives were to determine the prevalence of residents interested in pursuing research and other career options as part of their practice, and to identify the factors associated with interest in research. Method: Data from a national online survey of 207 Canadian psychiatry residents from a total of 853 (24.3% response rate) were examined. The main outcome was interest in research as part of residents’ future psychiatrist practice. Bivariate and multivariate analyses were performed to identify demographic and vocational variables associated with research interest. Results: Interest in research decreases by 76% between the first and fifth year of psychiatry residency (OR 0.76 per year, 95% CI 0.60 to 0.97). Training in a department with a residency research track did not correlate with increased research interest (χ2 = 0.007, df = 1, P = 0.93). Conclusions: Exposing and engaging psychiatry residents in research as early as possible in residency training appears key to promoting future research interest. Psychiatry residency programs and research tracks could consider emphasizing research training initiatives and protected research time early in residency. PMID:27253699

Recovery and recycling practices in municipal solid waste management in Lagos, Nigeria

International Nuclear Information System (INIS)

Kofoworola, O.F.

2007-01-01

The population of Lagos, the largest city in Nigeria, increased seven times from 1950 to 1980 with a current population of over 10 million inhabitants. The majority of the city's residents are poor. The residents make a heavy demand on resources and, at the same time, generate large quantities of solid waste. Approximately 4 million tonnes of municipal solid waste (MSW) is generated annually in the city, including approximately 0.5 million of untreated industrial waste. This is approximately 1.1 kg/cap/day. Efforts by the various waste management agencies set up by the state government to keep its streets and neighborhoods clean have achieved only minimal success. This is because more than half of these wastes are left uncollected from the streets and the various locations due to the inadequacy and inefficiency of the waste management system. Whilst the benefits of proper solid waste management (SWM), such as increased revenues for municipal bodies, higher productivity rate, improved sanitation standards and better health conditions, cannot be overemphasized, it is important that there is a reduction in the quantity of recoverable materials in residential and commercial waste streams to minimize the problem of MSW disposal. This paper examines the status of recovery and recycling in current waste management practice in Lagos, Nigeria. Existing recovery and recycling patterns, recovery and recycling technologies, approaches to materials recycling, and the types of materials recovered from MSW are reviewed. Based on these, strategies for improving recovery and recycling practices in the management of MSW in Lagos, Nigeria are suggested

Measurement of residence time distribution of liquid phase in an industrial-scale continuous pulp digester using radiotracer technique

International Nuclear Information System (INIS)

Sheoran, Meenakshi; Goswami, Sunil; Pant, Harish J.; Biswal, Jayashree; Sharma, Vijay K.; Chandra, Avinash; Bhunia, Haripada; Bajpai, Pramod K.; Rao, S. Madhukar; Dash, A.

2016-01-01

A series of radiotracer experiments was carried out to measure residence time distribution (RTD) of liquid phase (alkali) in an industrial-scale continuous pulp digester in a paper industry in India. Bromine-82 as ammonium bromide was used as a radiotracer. Experiments were carried out at different biomass and white liquor flow rates. The measured RTD data were treated and mean residence times in individual digester tubes as well in the whole digester were determined. The RTD was also analyzed to identify flow abnormalities and investigate flow dynamics of the liquid phase in the pulp digester. Flow channeling was observed in the first section (tube 1) of the digester. Both axial dispersion and tanks-in-series with backmixing models preceded with a plug flow component were used to simulate the measured RTD and quantify the degree of axial mixing. Based on the study, optimum conditions for operating the digester were proposed. - Highlights: • Radiotracer experiments were conducted to measure RTD of liquid phase in a pulp digester • Mean residence times of white liquor were measured • Axial dispersion and tanks-in-series models were used to investigate flow patterns • Parallel flow paths were observed in first section of the digester • Optimized flow rates of biomass and liquor were obtained

Extra-regional residence time as a correlate of plant invasiveness: European archaeophytes in North America

Czech Academy of Sciences Publication Activity Database

La Sorte, F. A.; Pyšek, Petr

2009-01-01

Roč. 90, č. 9 (2009), s. 2589-2597 ISSN 0012-9658 R&D Projects: GA MŠk LC06073 Grant - others:Evropská komise(XE) GOCE-CT-2003-506675 Institutional research plan: CEZ:AV0Z60050516 Keywords : residence time * archaeophyte * North America Subject RIV: EF - Botanics Impact factor: 4.411, year: 2009

Common Factors Among Family Medicine Residents Who Encounter Difficulty.

Science.gov (United States)

Binczyk, Natalia M; Babenko, Oksana; Schipper, Shirley; Ross, Shelley

2018-04-01

Residents in difficulty are costly to programs in both time and resources, and encountering difficulty can be emotionally harmful to residents. Approximately 10% of residents will encounter difficulty at some point in training. While there have been several studies looking at common factors among residents who encounter difficulty, some of the findings are inconsistent. The objective of this study was to determine whether there are common factors among the residents who encounter difficulty during training in a large Canadian family medicine residency program. Secondary data analysis was performed on archived resident files from a Canadian family medicine residency program. Residents who commenced an urban family medicine residency program between the years of 2006 and 2014 were included in the study. Five hundred nine family medicine residents were included in data analysis. Residents older than 30 years were 2.33 times (95% CI: 1.27-4.26) more likely to encounter difficulty than residents aged 30 years or younger. Nontransfer residents were 8.85 times (95% CI: 1.17-66.67) more likely to encounter difficulty than transfer residents. The effects of sex, training site, international medical graduate status, and rotation order on the likelihood of encountering difficulty were nonsignificant. Older and nontransfer residents may be facing unique circumstances and may benefit from additional support from the program.

A non-discrete method for computation of residence time in fluid mechanics simulations.

Science.gov (United States)

Esmaily-Moghadam, Mahdi; Hsia, Tain-Yen; Marsden, Alison L

2013-11-01

Cardiovascular simulations provide a promising means to predict risk of thrombosis in grafts, devices, and surgical anatomies in adult and pediatric patients. Although the pathways for platelet activation and clot formation are not yet fully understood, recent findings suggest that thrombosis risk is increased in regions of flow recirculation and high residence time (RT). Current approaches for calculating RT are typically based on releasing a finite number of Lagrangian particles into the flow field and calculating RT by tracking their positions. However, special care must be taken to achieve temporal and spatial convergence, often requiring repeated simulations. In this work, we introduce a non-discrete method in which RT is calculated in an Eulerian framework using the advection-diffusion equation. We first present the formulation for calculating residence time in a given region of interest using two alternate definitions. The physical significance and sensitivity of the two measures of RT are discussed and their mathematical relation is established. An extension to a point-wise value is also presented. The methods presented here are then applied in a 2D cavity and two representative clinical scenarios, involving shunt placement for single ventricle heart defects and Kawasaki disease. In the second case study, we explored the relationship between RT and wall shear stress, a parameter of particular importance in cardiovascular disease.

Parental leave for residents and pediatric training programs.

Science.gov (United States)

2013-02-01

The American Academy of Pediatrics (AAP) is committed to the development of rational, equitable, and effective parental leave policies that are sensitive to the needs of pediatric residents, families, and developing infants and that enable parents to spend adequate and good-quality time with their young children. It is important for each residency program to have a policy for parental leave that is written, that is accessible to residents, and that clearly delineates program practices regarding parental leave. At a minimum, a parental leave policy for residents and fellows should conform legally with the Family Medical Leave Act as well as with respective state laws and should meet institutional requirements of the Accreditation Council for Graduate Medical Education for accredited programs. Policies should be well formulated and communicated in a culturally sensitive manner. The AAP advocates for extension of benefits consistent with the Family Medical Leave Act to all residents and interns beginning at the time that pediatric residency training begins. The AAP recommends that regardless of gender, residents who become parents should be guaranteed 6 to 8 weeks, at a minimum, of parental leave with pay after the infant's birth. In addition, in conformance with federal law, the resident should be allowed to extend the leave time when necessary by using paid vacation time or leave without pay. Coparenting, adopting, or fostering of a child should entitle the resident, regardless of gender, to the same amount of paid leave (6-8 weeks) as a person who takes maternity/paternity leave. Flexibility, creativity, and advanced planning are necessary to arrange schedules that optimize resident education and experience, cultivate equity in sharing workloads, and protect pregnant residents from overly strenuous work experiences at critical times of their pregnancies.

2003 survey of Canadian radiation oncology residents

International Nuclear Information System (INIS)

Yee, Don; Fairchild, Alysa; Keyes, Mira; Butler, Jim; Dundas, George

2005-01-01

Purpose: Radiation oncology's popularity as a career in Canada has surged in the past 5 years. Consequently, resident numbers in Canadian radiation oncology residencies are at all-time highs. This study aimed to survey Canadian radiation oncology residents about their opinions of their specialty and training experiences. Methods and Materials: Residents of Canadian radiation oncology residencies that enroll trainees through the Canadian Resident Matching Service were identified from a national database. Residents were mailed an anonymous survey. Results: Eight of 101 (7.9%) potential respondents were foreign funded. Fifty-two of 101 (51.5%) residents responded. A strong record of graduating its residents was the most important factor residents considered when choosing programs. Satisfaction with their program was expressed by 92.3% of respondents, and 94.3% expressed satisfaction with their specialty. Respondents planning to practice in Canada totaled 80.8%, and 76.9% plan to have academic careers. Respondents identified job availability and receiving adequate teaching from preceptors during residency as their most important concerns. Conclusions: Though most respondents are satisfied with their programs and specialty, job availability and adequate teaching are concerns. In the future, limited time and resources and the continued popularity of radiation oncology as a career will magnify the challenge of training competent radiation oncologists in Canada

Identifying Gaps and Launching Resident Wellness Initiatives: The 2017 Resident Wellness Consensus Summit

Directory of Open Access Journals (Sweden)

Nicole Battaglioli

2018-02-01

Full Text Available Introduction: Burnout, depression, and suicidality among residents of all specialties have become a critical focus for the medical education community, especially among learners in graduate medical education. In 2017 the Accreditation Council for Graduate Medical Education (ACGME updated the Common Program Requirements to focus more on resident wellbeing. To address this issue, one working group from the 2017 Resident Wellness Consensus Summit (RWCS focused on wellness program innovations and initiatives in emergency medicine (EM residency programs. Methods: Over a seven-month period leading up to the RWCS event, the Programmatic Initiatives workgroup convened virtually in the Wellness Think Tank, an online, resident community consisting of 142 residents from 100 EM residencies in North America. A 15-person subgroup (13 residents, two faculty facilitators met at the RWCS to develop a public, central repository of initiatives for programs, as well as tools to assist programs in identifying gaps in their overarching wellness programs. Results: An online submission form and central database of wellness initiatives were created and accessible to the public. Wellness Think Tank members collected an initial 36 submissions for the database by the time of the RWCS event. Based on general workplace, needs-assessment tools on employee wellbeing and Kern’s model for curriculum development, a resident-based needs-assessment survey and an implementation worksheet were created to assist residency programs in wellness program development. Conclusion: The Programmatic Initiatives workgroup from the resident-driven RWCS event created tools to assist EM residency programs in identifying existing initiatives and gaps in their wellness programs to meet the ACGME’s expanded focus on resident wellbeing.

[Work satisfaction, quality of life and leisure time of residents at the Soroka University Medical Center, Beer Sheba, Israel].

Science.gov (United States)

Acker, Asaf; Perry, Zvi; Reuveni, Haim; Toker, Asaf

2009-02-01

Work dissatisfaction among physicians worldwide continues to rise over the last few decades, mainly due to declining professional prestige, tack of self fulfillment, time pressure and tack of leisure time. Physicians' burnout is a major result of dissatisfaction, causing doctors to leave the medical profession, and to provide lower quality of care. To examine the work satisfaction, quality of life and leisure time of residents in the Soroka University Medical Center. A validated questionnaire was delivered during the second half of 2004 to 252 residents in the Soroka University Medical Center The data was analyzed using the SPSS 12 for windows program. Descriptive analysis, parametric Students' T Test [where pleisure time. Further attention must be given to these matters--a step which will eventually improve patient care, and delay, to some extent, the burnout of physicians.

Implementation of a "Flipped Classroom" for Neurosurgery Resident Education.

Science.gov (United States)

Girgis, Fady; Miller, Jonathan P

2018-01-01

Engaging residents across a multiyear training spectrum is challenging given the heterogeneity of experience and limited time available for educational activities. A "flipped classroom" model, in which residents prepare ahead of time for mentored topic discussions, has potential advantages. We implemented a curriculum consisting of topics distributed across the specialty. Weekly, each resident was randomly assigned to research a specific aspect of an assigned topic appropriate to his or her level of experience: junior residents about what characterizes each clinical entity, midlevel residents about when to intervene, and chief residents about how to administer treatment. Residents completed an anonymous survey 6 months after implementation. Board examination performance was assessed before and after implementation. A total of 12 residents participated in the program. Weekly, 1.75±0.40 hours were spent in preparation, with senior residents reporting less time than junior residents. All residents indicated that the accumulation of experience across 7 years of residency was a major advantage of this program, and all preferred it to lectures. Performance on the board examination significantly increased after implementation (from 316±36 to 468±45, pflipped classroom is a viable approach to resident education and is associated with increased engagement and improved performance using validated knowledge-assessment tools.

The use of 41Ar to investigate residence time distribution (RTD) in petrochemical industry

International Nuclear Information System (INIS)

Sirelkhatim, D. A.; Hassan, B. A.; ElTayeb, M. A. H.; Hills, A. E.

2004-01-01

Residence time measurements were carried out on a wax slurry bed reactor (SBR) and on a pilot FTDU reactor by means of radioisotope tracer technology using Ar-41 as tracer gas. Representative results were obtained as the behaviour of the gas in the SBR showed channeling downstream and in the FTDU, possible different mixing zones in the upper portion and the occurrence of air pockets was evident. ( Authors)

Dynamics of nitrate production and removal as a function of residence time in the hyporheic zone

Science.gov (United States)

Jay P. Zarnetske; Roy Haggerty; Steven M. Wondzell; Michelle A. Baker

2011-01-01

Biogeochemical reactions associated with stream nitrogen cycling, such as nitrification and denitrification, can be strongly controlled by water and solute residence times in the hyporheic zone (HZ). We used a whole-stream steady state 15N-Iabeled nitrate and conservative tracer addition to investigate the spatial and temporal physiochemical...

CFD simulation of solids suspension in stirred tanks: Review

Directory of Open Access Journals (Sweden)

Ochieng Aoyi

2010-01-01

Full Text Available Many chemical reactions are carried out using stirred tanks, and the efficiency of such systems depends on the quality of mixing, which has been a subject of research for many years. For solid-liquid mixing, traditionally the research efforts were geared towards determining mixing features such as off-bottom solid suspension using experimental techniques. In a few studies that focused on the determination of solids concentration distribution, some methods that have been used have not been accurate enough to account for some small scale flow mal-distribution such as the existence of dead zones. The present review shows that computational fluid dynamic (CFD techniques can be used to simulate mixing features such as solids off-bottom suspension, solids concentration and particle size distribution and cloud height. Information on the effects of particle size and particle size distribution on the solids concentration distribution is still scarce. Advancement of the CFD modeling is towards coupling the physical and kinetic data to capture mixing and reaction at meso- and micro-scales. Solids residence time distribution is important for the design; however, the current CFD models do not predict this parameter. Some advances have been made in recent years to apply CFD simulation to systems that involve fermentation and anaerobic processes. In these systems, complex interaction between the biochemical process and the hydrodynamics is still not well understood. This is one of the areas that still need more attention.

Ophthalmology resident surgical competency: a national survey.

Science.gov (United States)

Binenbaum, Gil; Volpe, Nicholas J

2006-07-01

To describe the prevalence, management, and career outcomes of ophthalmology residents who struggle with surgical competency and to explore related educational issues. Fourteen-question written survey. Fifty-eight program directors at Accreditation Council on Graduate Medical Education-accredited, United States ophthalmology residency programs, representing a total of 2179 resident graduates, between 1991 and 2000. Study participants completed a mailed, anonymous survey whose format combined multiple choice and free comment questions. Number of surgically challenged residents, types of problems identified, types of remediation, final departmental decision at the end of residency, known career outcomes, and residency program use of microsurgical skills laboratories and applicant screening tests. One hundred ninety-nine residents (9% overall; 10% mean per program) were labeled as having trouble mastering surgical skills. All of the programs except 2 had encountered such residents. The most frequently cited problems were poor hand-eye coordination (24%) and poor intraoperative judgment (22%). Most programs were supportive and used educational rather than punitive measures, the most common being extra practice-laboratory time (32%), scheduling cases with the best teaching surgeon (23%), and counseling (21%). Nearly one third (31%) of residents were believed to have overcome their difficulties before graduation. Other residents were encouraged to pursue medical ophthalmology (22%) or to obtain further surgical training through a fellowship (21%) or a supervised practice setting (12%); these residents were granted a departmental statement of satisfactory completion of residency for Board eligibility. Twelve percent were asked to leave residency. Of reported career outcomes, 92% of residents were practicing ophthalmology, 65% as surgical and 27% as medical ophthalmologists. Ninety-eight percent of residency programs had microsurgical practice facilities, 64% had a formal

A residence-time-based transport approach for the groundwater pathway in performance assessment models

Science.gov (United States)

Robinson, Bruce A.; Chu, Shaoping

2013-03-01

This paper presents the theoretical development and numerical implementation of a new modeling approach for representing the groundwater pathway in risk assessment or performance assessment model of a contaminant transport system. The model developed in the present study, called the Residence Time Distribution (RTD) Mixing Model (RTDMM), allows for an arbitrary distribution of fluid travel times to be represented, to capture the effects on the breakthrough curve of flow processes such as channelized flow and fast pathways and complex three-dimensional dispersion. Mathematical methods for constructing the model for a given RTD are derived directly from the theory of residence time distributions in flowing systems. A simple mixing model is presented, along with the basic equations required to enable an arbitrary RTD to be reproduced using the model. The practical advantages of the RTDMM include easy incorporation into a multi-realization probabilistic simulation; computational burden no more onerous than a one-dimensional model with the same number of grid cells; and straightforward implementation into available flow and transport modeling codes, enabling one to then utilize advanced transport features of that code. For example, in this study we incorporated diffusion into the stagnant fluid in the rock matrix away from the flowing fractures, using a generalized dual porosity model formulation. A suite of example calculations presented herein showed the utility of the RTDMM for the case of a radioactive decay chain, dual porosity transport and sorption.

Calculation of residence times and radiation doses using the standard PC software Excel

International Nuclear Information System (INIS)

Herzog, H.; Zilken, H.; Niederbremer, A.; Friedrich, W.; Mueller-Gaertner, H.W.

1997-01-01

We developed a program which aims to facilitate the calculation of radiation doses to single organs and the whole body. IMEDOSE uses Excel to include calculations, graphical displays, and interactions with the user in a single general-purpose PC software tool. To start the procedure the input data are copied into a spreadsheet. They must represent percentage uptake values of several organs derived from measurements in animals or humans. To extrapolate these data up to seven half-lives of the radionuclide, fitting to one or two exponentional functions is included and can be checked by the user. By means of the approximate time-activity information the cumulated activity or residence times are calculated. Finally these data are combined with the absorbed fraction doses (S-values) given by MIRD pamphlet No. 11 to yield radiation doses, the effective dose equivalent and the effective dose. These results are presented in a final table. Interactions are realized with push-buttons and drop-down menus. Calculations use the Visual Basic tool of Excel. In order to test our program, biodistribution data of fluorine-18 fluorodeoxyglucose were taken from the literature (Meija et al., J Nucl Med 1991; 32:699-706). For a 70-kg adult the resulting radiation doses of all target organs listed in MIRD 11 were different from the ICRP 53 values by 1%±18% on the average. When the residence times were introduced into MIRDOSE3 (Stabin, J Nucl Med 1996; 37:538-546) the mean difference between our results and those of MIRDOSE3 was -3%±6%. Both outcomes indicate the validity of the present approach. (orig.)

Calculation of residence times and radiation doses using the standard PC software Excel.

Science.gov (United States)

Herzog, H; Zilken, H; Niederbremer, A; Friedrich, W; Müller-Gärtner, H W

1997-12-01

We developed a program which aims to facilitate the calculation of radiation doses to single organs and the whole body. IMEDOSE uses Excel to include calculations, graphical displays, and interactions with the user in a single general-purpose PC software tool. To start the procedure the input data are copied into a spreadsheet. They must represent percentage uptake values of several organs derived from measurements in animals or humans. To extrapolate these data up to seven half-lives of the radionuclide, fitting to one or two exponentional functions is included and can be checked by the user. By means of the approximate time-activity information the cumulated activity or residence times are calculated. Finally these data are combined with the absorbed fraction doses (S-values) given by MIRD pamphlet No. 11 to yield radiation doses, the effective dose equivalent and the effective dose. These results are presented in a final table. Interactions are realized with push-buttons and drop-down menus. Calculations use the Visual Basic tool of Excel. In order to test our program, biodistribution data of fluorine-18 fluorodeoxyglucose were taken from the literature (Meija et al., J Nucl Med 1991; 32:699-706). For a 70-kg adult the resulting radiation doses of all target organs listed in MIRD 11 were different from the ICRP 53 values by 1%+/-18% on the average. When the residence times were introduced into MIRDOSE3 (Stabin, J Nucl Med 1996; 37:538-546) the mean difference between our results and those of MIRDOSE3 was -3%+/-6%. Both outcomes indicate the validity of the present approach.

Calculation of residence times and radiation doses using the standard PC software Excel

Energy Technology Data Exchange (ETDEWEB)

Herzog, H.; Zilken, H.; Niederbremer, A.; Friedrich, W. [Institute of Medicine, Research Center Juelich, Juelich (Germany); Mueller-Gaertner, H.W. [Institute of Medicine, Research Center Juelich, Juelich (Germany)]|[Department of Nuclear Medicine, Heinrich-Heine University Hospital Duesseldorf (Germany)

1997-12-01

We developed a program which aims to facilitate the calculation of radiation doses to single organs and the whole body. IMEDOSE uses Excel to include calculations, graphical displays, and interactions with the user in a single general-purpose PC software tool. To start the procedure the input data are copied into a spreadsheet. They must represent percentage uptake values of several organs derived from measurements in animals or humans. To extrapolate these data up to seven half-lives of the radionuclide, fitting to one or two exponentional functions is included and can be checked by the user. By means of the approximate time-activity information the cumulated activity or residence times are calculated. Finally these data are combined with the absorbed fraction doses (S-values) given by MIRD pamphlet No. 11 to yield radiation doses, the effective dose equivalent and the effective dose. These results are presented in a final table. Interactions are realized with push-buttons and drop-down menus. Calculations use the Visual Basic tool of Excel. In order to test our program, biodistribution data of fluorine-18 fluorodeoxyglucose were taken from the literature (Meija et al., J Nucl Med 1991; 32:699-706). For a 70-kg adult the resulting radiation doses of all target organs listed in MIRD 11 were different from the ICRP 53 values by 1%{+-}18% on the average. When the residence times were introduced into MIRDOSE3 (Stabin, J Nucl Med 1996; 37:538-546) the mean difference between our results and those of MIRDOSE3 was -3%{+-}6%. Both outcomes indicate the validity of the present approach. (orig.) With 5 figs., 2 tabs., 18 refs.

Residence time distribution measurements in a pilot-scale poison tank using radiotracer technique.

Science.gov (United States)

Pant, H J; Goswami, Sunil; Samantray, J S; Sharma, V K; Maheshwari, N K

2015-09-01

Various types of systems are used to control the reactivity and shutting down of a nuclear reactor during emergency and routine shutdown operations. Injection of boron solution (borated water) into the core of a reactor is one of the commonly used methods during emergency operation. A pilot-scale poison tank was designed and fabricated to simulate injection of boron poison into the core of a reactor along with coolant water. In order to design a full-scale poison tank, it was desired to characterize flow of liquid from the tank. Residence time distribution (RTD) measurement and analysis was adopted to characterize the flow dynamics. Radiotracer technique was applied to measure RTD of aqueous phase in the tank using Bromine-82 as a radiotracer. RTD measurements were carried out with two different modes of operation of the tank and at different flow rates. In Mode-1, the radiotracer was instantaneously injected at the inlet and monitored at the outlet, whereas in Mode-2, the tank was filled with radiotracer and its concentration was measured at the outlet. From the measured RTD curves, mean residence times (MRTs), dead volume and fraction of liquid pumped in with time were determined. The treated RTD curves were modeled using suitable mathematical models. An axial dispersion model with high degree of backmixing was found suitable to describe flow when operated in Mode-1, whereas a tanks-in-series model with backmixing was found suitable to describe flow of the poison in the tank when operated in Mode-2. The results were utilized to scale-up and design a full-scale poison tank for a nuclear reactor. Copyright © 2015 Elsevier Ltd. All rights reserved.

Using heat as a tracer to estimate spatially distributed mean residence times in the hyporheic zone of a riffle-pool sequence

Science.gov (United States)

Naranjo, Ramon C.

2013-01-01

Biochemical reactions that occur in the hyporheic zone are highly dependent on the time solutes that are in contact with sediments of the riverbed. In this investigation, we developed a 2-D longitudinal flow and solute-transport model to estimate the spatial distribution of mean residence time in the hyporheic zone. The flow model was calibrated using observations of temperature and pressure, and the mean residence times were simulated using the age-mass approach for steady-state flow conditions. The approach used in this investigation includes the mixing of different ages and flow paths of water through advection and dispersion. Uncertainty of flow and transport parameters was evaluated using standard Monte Carlo and the generalized likelihood uncertainty estimation method. Results of parameter estimation support the presence of a low-permeable zone in the riffle area that induced horizontal flow at a shallow depth within the riffle area. This establishes shallow and localized flow paths and limits deep vertical exchange. For the optimal model, mean residence times were found to be relatively long (9–40.0 days). The uncertainty of hydraulic conductivity resulted in a mean interquartile range (IQR) of 13 days across all piezometers and was reduced by 24% with the inclusion of temperature and pressure observations. To a lesser extent, uncertainty in streambed porosity and dispersivity resulted in a mean IQR of 2.2 and 4.7 days, respectively. Alternative conceptual models demonstrate the importance of accounting for the spatial distribution of hydraulic conductivity in simulating mean residence times in a riffle-pool sequence.

Real-time boronization in PBX-M using erosion of solid boronized targets

International Nuclear Information System (INIS)

Kugel, H.W.; Timberlake, J.; Bell, R.; LeBlanc, B.; Okabayashi, M.; Paul, S.; Tighe, W.; Hirooka, Y.

1994-11-01

Thirty one real-time boronizations were applied to PBX-M using the plasma erosion of solid target probes. More than 17 g of boron were deposited in PBX-M using this technique. The probes were positioned at the edge plasma to optimize vaporization and minimize spallation. Auger depth profile analysis of poloidal and toroidal deposition sample coupon arrays indicate that boron was transported by the plasma around the torus and deep into the divertors. During discharges with continuous real-time boronization, low-Z and high-Z impurities decreased rapidly as plasma surfaces were covered during the first 20-30 discharges. After boronization, a short-term improvement in plasma conditions persisted prior to significant boron erosion from plasma surfaces, and a longer term, but less significant improvement persisted as boron farther from the edge continued gettering. Real-time solid target boronization has been found to be very effective for accelerating conditioning to new regimes and maintaining high performance plasma conditions

Current integrated cardiothoracic surgery residents: a Thoracic Surgery Residents Association survey.

Science.gov (United States)

Tchantchaleishvili, Vakhtang; LaPar, Damien J; Stephens, Elizabeth H; Berfield, Kathleen S; Odell, David D; DeNino, Walter F

2015-03-01

After approval by the Thoracic Surgery Residency Review Committee in 2007, 6-year integrated cardiothoracic surgery (I-6) residency programs have gained in popularity. We sought to assess and objectively quantify the level of satisfaction I-6 residents have with their training and to identify areas of improvement for future curriculum development. A completely anonymous, electronic survey was created by the Thoracic Surgery Residents Association that asked the responders to provide demographic information, specialty interest, and lifestyle priorities, and to rate their experience and satisfaction with I-6 residency. The survey was distributed nationwide to all residents in I-6 programs approved by the Accreditation Council for Graduate Medical Education. Of a total of 88 eligible I-6 residents, 49 completed the survey (55.7%). Career choice satisfaction was high (75.5%), as was overall satisfaction with integrated training (83.7%). The majority (77.6%) were interested in cardiac surgery. Overall, the responders reported sufficient time for life outside of the hospital (57.1%), but experienced conflicts between work obligations and personal life at least sometimes (75.5%). Early exposure to cardiothoracic surgery was reported as the dominant advantage of the I-6 model, whereas variable curriculum structure and unclear expectations along with poor integration with general surgery training ranked highest among perceived disadvantages. Current I-6 residents are largely satisfied with the integrated training model and report a reasonable work/life balance. The focused nature of training is the primary perceived advantage of the integrated pathway. Curriculum variability and poor integration with general surgery training are identified by residents as primary areas of concern. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Design report for the residence time extension of KNK II/2 from 455 to 720 equivalent full-power days

International Nuclear Information System (INIS)

Schade, H.-J.; Steinmetz, B.; Wehmann, U.

1985-05-01

The report describes the performance of the whole reactor and of its assemblies and their components during the residence time extension of the second core of KNK II from the foreseen value of 455 equivalent full-power days (efpd) to 720 efpd. By this extension existing reactivity and design reserves can be utilized, and the burnup of the test zone assemblies can be increased towards the level aimed at for future sodium breeder reactors. The investigations about the static and the dynamic behavior of the core with its components and of the heat transfer systems under nominal and accidental conditions show, that the plant can be safely operated during the residence time extension [de

Hydrochemistry, origin and residence time of deep groundwater in the Yuseong area

International Nuclear Information System (INIS)

Koh, Yong Kwon; Kim, Geon Young; Bae, Dae Seok; Park, Kyung Woo

2005-01-01

As a part of the radioactive waste disposal research program in Korea, the geological, hydrogeological and hydrogeochemical investigations have been carried out in the Yuseong area (KAERI). The temperature or groundwater is measured up to 24 .deg. C and thermal gradient is obtained, to 0.26 .deg. C/100m. pH of groundwater at upper section shows about 7 and the pH of groundwater of 200m below surface reaches almost constant value as 9.9∼10.3. The redox potential of groundwater varied with depth and more negative values were recognized in deep groundwater. The redox potential of deep groundwater, main factor of U solubility, was measured up to -150 mV. These high pH and reduced conditions indicates that the maximum U concentration in groundwater would be limited by the equilibrium solubility of U minerals. The chemistry of shallow groundwater shows Ca-HCO 3 or Ca-Na-HCO 3 type, whereas the deep groundwater belongs to typical Na-HCO 3 type. The chemistry of groundwater below 250m from the surface is constant with depth, indicating that the extent of water-rock reaction is almost unique, which is controlled by the residence time of groundwater. The carbon isotope data (δ 13 C) of groundwater show the contribution of carbon from either that microbial oxidation of organic matter or carbon dioxide from plant respiration. The measurement and interpretation of C-14 indicate that the residence time of borehole deep groundwater ranges from about 2,000 to 6,000 yr BP. The high δ 34 S so4 value of groundwater indicate that the sulfate reduction might be occurred in the deep environment

Ontario Radiation Oncology Residents' Needs in the First Postgraduate Year-Residents' Perspective Survey

International Nuclear Information System (INIS)

Szumacher, Ewa; Warner, Eiran; Zhang Liying; Kane, Gabrielle; Ackerman, Ida; Nyhof-Young, Joyce; Agboola, Olusegun; Metz, Catherine de; Rodrigues, George; Voruganti, Sachi; Rappolt, Susan

2007-01-01

Purpose: To assess radiation oncology residents' needs and satisfaction in their first postgraduate year (PGY-1) in the province of Ontario. Methods and Materials: Of 62 radiation oncology residents, 58 who had completed their PGY-1 and were either enrolled or had graduated in 2006 were invited to participate in a 31-item survey. The questionnaire explored PGY-1 residents' needs and satisfaction in four domains: clinical workload, faculty/learning environment, stress level, and discrimination/harassment. The Fisher's exact and Wilcoxon nonparametric tests were used to determine relationships between covariate items and summary scores. Results: Of 58 eligible residents, 44 (75%) responded. Eighty-four percent of residents felt that their ward and call duties were appropriate. More than 50% of respondents indicated that they often felt isolated from their radiation oncology program. Only 77% agreed that they received adequate feedback, and 40% received sufficient counseling regarding career planning. More than 93% of respondents thought that faculty members had contributed significantly to their learning experience. Approximately 50% of residents experienced excessive stress and inadequate time for leisure or for reading the medical literature. Less than 10% of residents indicated that they had been harassed or experienced discrimination. Eighty-three percent agreed or strongly agreed that their PGY-1 experience had been outstanding. Conclusions: Most Ontario residents were satisfied with their PGY-1 training program. More counseling by radiation oncology faculty members should be offered to help residents with career planning. The residents might also benefit from more exposure to 'radiation oncology' and an introduction to stress management strategies

Residence Time Distribution of Solid Particles in High-Aspect Ratio Multiple-Impeller Stirred Vessel

Czech Academy of Sciences Publication Activity Database

Scargiali, F.; Grisafi, F.; Čermáková, Jiřina; Machoň, V.; Brucato, A.

2004-01-01

Roč. 59, č. 17 (2004), s. 3601-3618 ISSN 0009-2509 Institutional research plan: CEZ:AV0Z4072921 Keywords : retention time distribution * twin systems approach * particle tracing Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.655, year: 2004

Taste, choice and timing: Investigating resident and carer preferences for meals in aged care homes.

Science.gov (United States)

Milte, Rachel; Ratcliffe, Julie; Chen, Gang; Miller, Michelle; Crotty, Maria

2018-03-01

There has been little empirical investigation of the preferences of people living in aged care homes for food services. The aim of the present study was to elicit consumer preferences and their willingness to pay for food service in aged care homes. Current residents or their family members were invited to take part in the discrete choice experiment questionnaire administered via interview. Of the 109 eligible residents and 175 eligible family members approached for consent 121 (43%) participated, including 43 residents. Participant preferences were influenced by food taste, choice in relation to serving size, timing of meal selection, visual appeal, and additional cost. Participants indicated they would be willing to pay an additional $24 (US$18.42) per week for food which tasted excellent and $8 (US$6.14) per week to have choice in serving sizes. The study found that respondents were willing to pay a premium to receive food that met their expectations of taste, and for a high level of control over serving sizes, which has implications for the funding and provision of food and dining in long-term care in the future. © 2018 The Authors Nursing & Health Sciences Published by John Wiley & Sons Australia, Ltd.

Pediatric dermatology training survey of United States dermatology residency programs.

Science.gov (United States)

Nijhawan, Rajiv I; Mazza, Joni M; Silverberg, Nanette B

2014-01-01

Variability exists in pediatric dermatology education for dermatology residents. We sought to formally assess the pediatric dermatology curriculum and experience in a dermatology residency program. Three unique surveys were developed for dermatology residents, residency program directors, and pediatric dermatology fellowship program directors. The surveys consisted of questions pertaining to residency program characteristics. Sixty-three graduating third-year residents, 51 residency program directors, and 18 pediatric dermatology fellowship program directors responded. Residents in programs with one or more full-time pediatric dermatologist were more likely to feel very competent treating children and were more likely to be somewhat or extremely satisfied with their pediatric curriculums than residents in programs with no full-time pediatric dermatologist (50.0% vs 5.9%, p = 0.002, and 85.3% vs 52.9%, p dermatology fellowships were much more likely to report being extremely satisfied than residents in programs without a pediatric dermatology fellowship (83.3% vs 21.2%; p dermatology residency programs to continue to strengthen their pediatric dermatology curriculums, especially through the recruitment of full-time pediatric dermatologists. © 2013 Wiley Periodicals, Inc.

Patient-Centered Handovers: Ethnographic Observations of Attending and Resident Physicians: Ethnographic Observations of Attending and Resident Physicians.

Science.gov (United States)

Mount-Campbell, Austin F; Rayo, Michael F; OʼBrien, James J; Allen, Theodore T; Patterson, Emily S

Handover communication improvement initiatives typically employ a "one size fits all" approach. A human factors perspective has the potential to guide how to tailor interventions to roles, levels of experience, settings, and types of patients. We conducted ethnographic observations of sign-outs by attending and resident physicians in 2 medical intensive care units at one institution. Digitally audiotaped data were manually analyzed for content using codes and time spent using box plots for emergent categories. A total of 34 attending and 58 resident physician handovers were observed. Resident physicians spent more time for "soon to be discharged" and "higher concern" patients than attending physicians. Resident physicians spent less time discussing patients which they had provided care for within the last 3 days ("handbacks"). The study suggested differences for how handovers were conducted for attending and resident physicians for 3 categories of patients; handovers differ on the basis of role or level of expertise, patient type, and amount of prior knowledge of the patient. The findings have implications for new directions for subsequent research and for how to tailor quality improvement interventions based upon the role, level of experience, level of prior knowledge, and patient categories.

Study of combustion properties of a solid propellant by highly time-resolved passive FTIR

Energy Technology Data Exchange (ETDEWEB)

Zhang, Liming; Zhang, Lin; Li, Yan; Liu, Bingping; Wang, Junde [Laboratory of Advanced Spectroscopy, Nanjing University of Science and Technology, Nanjing 210014 (China)

2006-10-15

With a time resolution of 0.125 s and a spectral resolution of 4 cm{sup -1}, emission spectra of the combustion process of a solid propellant were recorded by highly time-resolved passive FTIR. Some gaseous combustion products, such as H{sub 2}O, CO, CO{sub 2}, NO and HCl, were distinguished by the characteristic emission band of each molecule. The equation for flame temperature calculation based on the diatomic molecule emission fine structure theory was improved through judicious utilization of the spectral running number 'm' which makes the temperature measurement simpler and faster. Some combustion information of the solid propellant had been given including the characteristic spectral profile, the distribution of the absolute spectral energy, the distribution of the combustion flame temperature, and the concentration distributions of HCl and NO versus burning time. The results will provide theoretical and experimental bases for improving the formula and raising combustion efficiency of solid propellant, and developing the design of rocket motor, infrared guidance and antiguidance systems. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

Residence times and nitrate transport in ground water discharging to streams in the Chesapeake Bay Watershed

Science.gov (United States)

Lindsey, Bruce D.; Phillips, Scott; Donnelly, Colleen A.; Speiran, Gary K.; Plummer, Niel; Bohlke, John Karl; Focazio, Michael J.; Burton, William C.; Busenberg, Eurybiades

2003-01-01

One of the major water-quality problems in the Chesapeake Bay is an overabundance of nutrients from the streams and rivers that discharge to the Bay. Some of these nutrients are from nonpoint sources such as atmospheric deposition, agricultural manure and fertilizer, and septic systems. The effects of efforts to control nonpoint sources, however, can be difficult to quantify because of the lag time between changes at the land surface and the response in the base-flow (ground water) component of streams. To help resource managers understand the lag time between implementation of management practices and subsequent response in the nutrient concentrations in the base-flow component of streamflow, a study of ground-water discharge, residence time, and nitrate transport in springs throughout the Chesapeake Bay Watershed and in four smaller watersheds in selected hydrogeomorphic regions (HGMRs) was conducted. The four watersheds were in the Coastal Plain Uplands, Piedmont crystalline, Valley and Ridge carbonate, and Valley and Ridge siliciclastic HGMRs.A study of springs to estimate an apparent age of the ground water was based on analyses for concentrations of chlorofluorocarbons in water samples collected from 48 springs in the Chesapeake Bay Watershed. Results of the analysis indicate that median age for all the samples was 10 years, with the 25th percentile having an age of 7 years and the 75th percentile having an age of 13 years. Although the number of samples collected in each HGMR was limited, there did not appear to be distinct differences in the ages between the HGMRs. The ranges were similar between the major HGMRs above the Fall Line (modern to about 50 years), with only two HGMRs of small geographic extent (Piedmont carbonate and Mesozoic Lowland) having ranges of modern to about 10 years. The median values of all the HGMRs ranged from 7 to 11 years. Not enough samples were collected in the Coastal Plain for comparison. Spring samples showed slightly younger

Is the biochar produced from sewage sludge a good quality solid fuel?

Directory of Open Access Journals (Sweden)

Pulka Jakub

2016-12-01

Full Text Available The influence of sewage sludge torrefaction temperature on fuel properties was investigated. Non-lignocellulosic waste thermal treatment experiment was conducted within 1 h residence time, under the following temperatures: 200, 220, 240, 260, 280 and 300°C. Sawdust was used as lignocellulosic reference material. The following parameters of biochar have been measured: moisture, higher heating value, ash content, volatile compounds and sulfur content. Sawdust biochar has been confirmed to be a good quality solid fuel. High ash and sulfur content may be an obstacle for biochar energy reuse. The best temperature profile for sawdust torrefaction and fuel production for 1 h residence time was 220°C. At this temperature the product contained 84% of initial energy while decreased the mass by 25%. The best temperature profile for sewage sludge was 240°C. The energy residue was 91% and the mass residue was 85%. Higher temperatures in both cases caused excessive mass and energy losses.

Medical Student Interest in Flexible Residency Training Options.

Science.gov (United States)

Piotrowski, Madison; Stulberg, Debra; Egan, Mari

2018-05-01

Medical residents continue to experience high rates of burnout during residency training even after implementation of the 2003 Accreditation Council for Graduate Medical Education duty-hour restrictions. The purpose of this study is to determine medical student interest in flexible residency training options. Researchers developed an 11-question survey for second through fourth-year medical students. The populations surveyed included medical students who were: (1) attending the 2015 American Academy of Family Physicians National Conference, the 2015 Family Medicine Midwest Conference, and (2) enrolled at University of Chicago Pritzker School of Medicine, University of Illinois College of Medicine at Chicago, Drexel University College of Medicine, and Case Western Reserve University School of Medicine. The survey was completed by 789 medical students. Over half of medical students surveyed indicated that they would be interested in working part-time during some portion of their residency training (51%), and that access to part-time training options would increase their likelihood of applying to a particular residency program (52%). When given the option of three residency training schedules of varying lengths, 41% of male students and 60% of female students chose a 60-hour workweek, even when that meant extending the residency length by 33% and reducing their yearly salary to $39,000. There is considerable interest among medical students in access to part-time residency training options and reduced-hour residency programs. This level of interest indicates that offering flexible training options could be an effective recruitment tool for residency programs and could improve students' perception of their work-life balance during residency.

Timing of solid food introduction and obesity: Hong Kong's "children of 1997" birth cohort.

Science.gov (United States)

Lin, Shi Lin; Leung, Gabriel M; Lam, Tai Hing; Schooling, C Mary

2013-05-01

Some observational studies in Western settings show that early introduction of solid food is associated with subsequent obesity. However, introduction of solid food and obesity share social patterning. We examined the association of the timing of the introduction of solid food with BMI and overweight (including obesity) into adolescence in a developed non-Western setting, in which childhood obesity is less clearly socially patterned. We used generalized estimating equation models to estimate the adjusted associations of the timing of the introduction of solid food (8 months) with BMI z score and overweight (including obesity) at different growth phases (infancy, childhood, and puberty) in 7809 children (88% follow-up) from a Chinese birth cohort, "Children of 1997." We assessed if the associations varied with gender or breastfeeding. We used multiple imputation for missing exposure and confounders. The introduction of solid food at associated with lower family socioeconomic position (SEP) but was not clearly associated with BMI or overweight (including obesity) in infancy [mean difference in BMI z score: 0.01; 95% confidence interval (CI): -0.14 to 0.17], childhood (0.14; 95% CI: -0.11 to 0.40), or at puberty (0.22; 95% CI: -0.07 to 0.52), adjusted for SEP and infant and maternal characteristics. In a non-Western developed setting, there was no clear association of the early introduction of solid food with childhood obesity. Together with the inconsistent evidence from studies in Western settings, this finding suggests that any observed associations might simply be residual confounding by SEP.

Spatial distribution of triazine residues in a shallow alluvial aquifer linked to groundwater residence time.

Science.gov (United States)

Sassine, Lara; Le Gal La Salle, Corinne; Khaska, Mahmoud; Verdoux, Patrick; Meffre, Patrick; Benfodda, Zohra; Roig, Benoît

2017-03-01

At present, some triazine herbicides occurrence in European groundwater, 13 years after their use ban in the European Union, remains of great concern and raises the question of their persistence in groundwater systems due to several factors such as storage and remobilization from soil and unsaturated zone, limited or absence of degradation, sorption in saturated zones, or to continuing illegal applications. In order to address this problem and to determine triazine distribution in the saturated zone, their occurrence is investigated in the light of the aquifer hydrodynamic on the basis of a geochemical approach using groundwater dating tracers ( 3 H/ 3 He). In this study, atrazine, simazine, terbuthylazine, deethylatrazine, deisopropylatrazine, and deethylterbuthylazine are measured in 66 samples collected between 2011 and 2013 from 21 sampling points, on the Vistrenque shallow alluvial aquifer (southern France), covered by a major agricultural land use. The frequencies of quantification range from 100 to 56 % for simazine and atrazine, respectively (LQ = 1 ng L -1 ). Total triazine concentrations vary between 15 and 350 ng L -1 and show three different patterns with depth below the water table: (1) low concentrations independent of depth but related to water origin, (2) an increase in concentrations with depth in the aquifer related to groundwater residence time and triazine use prior to their ban, and (3) relatively high concentrations at low depths in the saturated zone more likely related to a slow desorption of these compounds from the soil and unsaturated zone. The triazine attenuation rate varies between 0.3 for waters influenced by surface water infiltration and 4.8 for water showing longer residence times in the aquifer, suggesting an increase in these rates with water residence time in the saturated zone. Increasing triazine concentrations with depth is consistent with a significant decrease in the use of these pesticides for the last 10 years on

Perioperative self-reflection among surgical residents.

Science.gov (United States)

Peshkepija, Andi N; Basson, Marc D; Davis, Alan T; Ali, Muhammad; Haan, Pam S; Gupta, Rama N; Hardaway, John C; Nebeker, Cody A; McLeod, Michael K; Osmer, Robert L; Anderson, Cheryl I

2017-09-01

We studied prevalence and predictors of meaningful self-reflection among surgical residents and with prompting/structured interventions, sought to improve/sustain resident skills. Residents from six programs recorded 1032 narrative self-reflective comments (120 residents), using a web-based platform. If residents identified something learned or to be improved, self-reflection was deemed meaningful. Independent variables PGY level, resident/surgeon gender, study site/Phase1: July2014-August2015 vs. Phase2: September2015-September2016) were analyzed. Meaningful self-reflection was documented in 40.6% (419/1032) of entries. PGY5's meaningfully self-reflected less than PGY1-4's, 26.1% vs. 49.6% (p = 0.002). In multivariate analysis, resident narratives during Phase 2 were 4.7 times more likely to engage in meaningful self-reflection compared to Phase1 entries (p self-reflection, compared to Phase1. Surgical residents uncommonly practice meaningful self-reflection, even when prompted, and PGY5/chief residents reflect less than more junior residents. Substantial/sustained improvements in resident self-reflection can occur with both training and interventions. Copyright © 2017 Elsevier Inc. All rights reserved.

Surgical resident learning styles: faculty and resident accuracy at identification of preferences and impact on ABSITE scores.

Science.gov (United States)

Kim, Roger H; Gilbert, Timothy; Ristig, Kyle; Chu, Quyen D

2013-09-01

As a consequence of surgical resident duty hour restrictions, there is a need for faculty to utilize novel teaching methods to convey information in a more efficient manner. The current paradigm of surgical training, which has not changed significantly since the time of Halsted, assumes that all residents assimilate information in a similar fashion. However, recent data has shown that learners have preferences for the ways in which they receive and process information. The VARK model categorizes learners as visual (V), aural (A), read/write (R), and kinesthetic (K). The VARK learning style preferences of surgical residents have not been previously evaluated. In this study, the preferred learning styles of general surgery residents were determined, along with faculty and resident perception of resident learning styles. In addition, we hypothesized that American Board of Surgery In-Training Exam (ABSITE) scores are associated with preference for a read/write (R) learning style. The Fleming VARK learning styles inventory was administered to all general surgery residents at a university hospital-based program. Responses on the inventory were scored to determine the preferred learning style for each resident. Faculty members were surveyed to determine their accuracy in identifying the preferred learning style of each resident. All residents were also surveyed to determine their accuracy in identifying their peers' VARK preferences. Resident ABSITE scores were examined for association with preferred learning styles. Twenty-nine residents completed the inventory. Most (18 of 29, 62%) had a multimodal preference, although more than a third (11 of 29, 38%) demonstrated a single-modality preference. Seventy-six percent of all residents (22 of 29) had some degree of kinesthetic (K) learning, while under 50% (14 of 29) were aural (A) learners. Although not significant, dominant (R) learners had the highest mean ABSITE scores. Faculty identified residents' learning styles

Electricity distribution within the future residence

Energy Technology Data Exchange (ETDEWEB)

Breeze, J.E.

1981-11-01

This study examined present residential wiring systems and identified their shortcomings. A list of the desirable attributes for future wiring systems is proposed. The outlook for the application to wiring systems of solid-state electronic devices is assessed. As further background for a proposed new wiring concept, the residential use of energy today and probable future trends are reviewed. Lastly, the concept of a distributed bus is proposed and developed on a conceptual basis for the residential wiring system of the future. The distributed bus concept can lead to the development of a residential wiring system to meet the following requirements: adaptable to meet probable future energy requirements for residences including alternative energy sources and energy storage; flexibility for servicing loads both in respect to location in the residence and to the size of the load; improved economy in the use of materials; capability for development as a designed or engineered system with factory assembled components and wiring harness; capability for expansion through the attachment of legs or auxillary rings; adaptable to any probable architectural residential development; capability for development to meet the requirements for ease of use and maintenance and with recognition of the growing importance of do-it-yourself repairs and alterations; and adaptable to the full range of solid-state electronics and micro-computer devices and controls including the concept of load control and management through the use of a central control module. 66 refs., 15 figs., 1 tab.

A 15-year review of the Stanford Internal Medicine Residency Program: predictors of resident satisfaction and dissatisfaction

Directory of Open Access Journals (Sweden)

Kahn JS

2017-08-01

Full Text Available James S Kahn,1–3 Ronald M Witteles,3,4 Kenneth W Mahaffey,3–5 Sumbul A Desai,2,3 Errol Ozdalga,2,3 Paul A Heidenreich1,3 1Veterans Affairs Palo Alto Health Care System, Palo Alto, 2Division of Primary Care and Population Health, 3Department of Medicine, 4Division of Cardiovascular Medicine, 5Stanford Center for Clinical Research, Stanford University School of Medicine, Stanford, CA, USA Introduction: Satisfaction with training and with educational experiences represents important internal medicine (IM programmatic goals. Graduates from IM residency programs are uniquely poised to provide insights into their educational and training experiences and to assess whether these experiences were satisfactory and relevant to their current employment. Methods: We surveyed former IM residents from the training program held during the years 2000–2015 at the Department of Medicine, Stanford University. The first part of the survey reviewed the IM residency program and the second part sought identifying data regarding gender, race, ethnicity, work, relationships, and financial matters. The primary outcome was satisfaction with the residency experience. Results: Of the 405 individuals who completed the Stanford IM residency program in the study period, we identified 384 (95% former residents with a known email address. Two hundred and one (52% former residents responded to the first part and 185 (48% answered both the parts of the survey. The mean age of the respondents was 36.9 years; 44% were female and the mean time from IM residency was 6.1 (±4.3 years. Fifty-eight percent reported extreme satisfaction with their IM residency experience. Predictors associated with being less than extremely satisfied included insufficient outpatient experience, insufficient international experience, insufficient clinical research experience, and insufficient time spent with family and peers. Conclusion: The residents expressed an overall high satisfaction rate with

Are All Competencies Equal in the Eyes of Residents? A Multicenter Study of Emergency Medicine Residents' Interest in Feedback.

Science.gov (United States)

Bentley, Suzanne; Hu, Kevin; Messman, Anne; Moadel, Tiffany; Khandelwal, Sorabh; Streich, Heather; Noelker, Joan

2017-01-01

Feedback, particularly real-time feedback, is critical to resident education. The emergency medicine (EM) milestones were developed in 2012 to enhance resident assessment, and many programs use them to provide focused resident feedback. The purpose of this study was to evaluate EM residents' level of interest in receiving real-time feedback on each of the 23 competencies/sub-competencies. This was a multicenter cross-sectional study of EM residents. We surveyed participants on their level of interest in receiving real-time on-shift feedback on each of the 23 competencies/sub-competencies. Anonymous paper or computerized surveys were distributed to residents at three four-year training programs and three three-year training programs with a total of 223 resident respondents. Residents rated their level of interest in each milestone on a six-point Likert-type response scale. We calculated average level of interest for each of the 23 sub-competencies, for all 223 respondents and separately by postgraduate year (PGY) levels of training. One-way analyses of variance were performed to determine if there were differences in ratings by level of training. The overall survey response rate across all institutions was 82%. Emergency stabilization had the highest mean rating (5.47/6), while technology had the lowest rating (3.24/6). However, we observed no differences between levels of training on any of the 23 competencies/sub-competencies. Residents seem to ascribe much more value in receiving feedback on domains involving high-risk, challenging procedural skills as compared to low-risk technical and communication skills. Further studies are necessary to determine whether residents' perceived importance of competencies/sub-competencies needs to be considered when developing an assessment or feedback program based on these 23 EM competencies/sub-competencies.

Receptor residence time trumps drug-likeness and oral bioavailability in determining efficacy of complement C5a antagonists

Science.gov (United States)

Seow, Vernon; Lim, Junxian; Cotterell, Adam J.; Yau, Mei-Kwan; Xu, Weijun; Lohman, Rink-Jan; Kok, W. Mei; Stoermer, Martin J.; Sweet, Matthew J.; Reid, Robert C.; Suen, Jacky Y.; Fairlie, David P.

2016-04-01

Drug discovery and translation are normally based on optimizing efficacy by increasing receptor affinity, functional potency, drug-likeness (rule-of-five compliance) and oral bioavailability. Here we demonstrate that residence time of a compound on its receptor has an overriding influence on efficacy, exemplified for antagonists of inflammatory protein complement C5a that activates immune cells and promotes disease. Three equipotent antagonists (3D53, W54011, JJ47) of inflammatory responses to C5a (3nM) were compared for drug-likeness, receptor affinity and antagonist potency in human macrophages, and anti-inflammatory efficacy in rats. Only the least drug-like antagonist (3D53) maintained potency in cells against higher C5a concentrations and had a much longer duration of action (t1/2 ~ 20 h) than W54011 or JJ47 (t1/2 ~ 1-3 h) in inhibiting macrophage responses. The unusually long residence time of 3D53 on its receptor was mechanistically probed by molecular dynamics simulations, which revealed long-lasting interactions that trap the antagonist within the receptor. Despite negligible oral bioavailability, 3D53 was much more orally efficacious than W54011 or JJ47 in preventing repeated agonist insults to induce rat paw oedema over 24 h. Thus, residence time on a receptor can trump drug-likeness in determining efficacy, even oral efficacy, of pharmacological agents.

Number needed to eat: pizza and resident conference attendance.

Science.gov (United States)

Cosimini, Michael J; Mackintosh, Liza; Chang, Todd P

2016-12-01

The didactic conference is a common part of the resident education curriculum. Given the demands of clinical responsibilities and restrictions on duty hours, maximising education is a challenge faced by all residency programmes. To date, little research exists with respect to how the provision of complimentary food affects physician and resident conference attendance. The objective of this study was to determine whether complimentary food improves resident arrival times and attendance at educational conferences and, furthermore, to test whether this provision is a potentially cost-effective tool for improving education. A retrospective review of 36 resident educational Friday noon conferences, including 1043 resident arrivals, was performed. Data were analysed for total attendance, arrival times, number needed to eat (NNE) and the percentage of residents arriving on time, and compared between days on which food was and was not provided. Median attendance was 3.7% higher (p = 0.04) on days on which food was provided, at a cost of US$46 for each additional resident in attendance. Arrival times were also statistically significantly improved when food was provided, with a median improvement of 0.7 minutes (p = 0.02) and an 11.0% increase in on-time arrivals (p < 0.001). The NNE was 10.6. Complimentary food improves both attendance and arrival times by a small, but statistically significant, degree. The provision of complimentary food can be considered as an incentive for attendance and on-time arrival at didactic educational sessions, although more cost-effective modalities may exist. © 2016 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

Solid-state framing camera with multiple time frames

Energy Technology Data Exchange (ETDEWEB)

Baker, K. L.; Stewart, R. E.; Steele, P. T.; Vernon, S. P.; Hsing, W. W.; Remington, B. A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2013-10-07

A high speed solid-state framing camera has been developed which can operate over a wide range of photon energies. This camera measures the two-dimensional spatial profile of the flux incident on a cadmium selenide semiconductor at multiple times. This multi-frame camera has been tested at 3.1 eV and 4.5 keV. The framing camera currently records two frames with a temporal separation between the frames of 5 ps but this separation can be varied between hundreds of femtoseconds up to nanoseconds and the number of frames can be increased by angularly multiplexing the probe beam onto the cadmium selenide semiconductor.

Improving Timely Resident Follow-Up and Communication of Results in Ambulatory Clinics Utilizing a Web-Based Audit and Feedback Module.

Science.gov (United States)

Boggan, Joel C; Swaminathan, Aparna; Thomas, Samantha; Simel, David L; Zaas, Aimee K; Bae, Jonathan G

2017-04-01

Failure to follow up and communicate test results to patients in outpatient settings may lead to diagnostic and therapeutic delays. Residents are less likely than attending physicians to report results to patients, and may face additional barriers to reporting, given competing clinical responsibilities. This study aimed to improve the rates of communicating test results to patients in resident ambulatory clinics. We performed an internal medicine, residency-wide, pre- and postintervention, quality improvement project using audit and feedback. Residents performed audits of ambulatory patients requiring laboratory or radiologic testing by means of a shared online interface. The intervention consisted of an educational module viewed with initial audits, development of a personalized improvement plan after Phase 1, and repeated real-time feedback of individual relative performance compared at clinic and program levels. Outcomes included results communicated within 14 days and prespecified "significant" results communicated within 72 hours. A total of 76 of 86 eligible residents (88%) reviewed 1713 individual ambulatory patients' charts in Phase 1, and 73 residents (85%) reviewed 1509 charts in Phase 2. Follow-up rates were higher in Phase 2 than Phase 1 for communicating results within 14 days and significant results within 72 hours (85% versus 78%, P  Communication of "significant" results was more likely to occur via telephone, compared with communication of nonsignificant results. Participation in a shared audit and feedback quality improvement project can improve rates of resident follow-up and communication of results, although communication gaps remained.

Residence Time Distribution (RTD) Prediction in Mixing Vessel via CFD Simulation Using Fluent: An Overview

International Nuclear Information System (INIS)

Mohd Rizal Mamat; Azraf Azman; Noraishah Othman

2011-01-01

A prototype mixing vessel has been developed by Industrial Technology Division and installed at a multiphase testing facility in MINT Tech Park. A task to investigate the mixing vessel performance using Computational Fluid Dynamics (CFD) has been undertaken using the available FLUENT software in Malaysian Nuclear Agency. This paper discusses the modeling and simulation done in obtaining the Residence Time Distribution (RTD) for the mixing vessel using FLUENT. (author)

Discharge residence of TLD tagged fish

International Nuclear Information System (INIS)

Romberg, G.P.; Prepejchal, W.

1974-01-01

Although visual observations suggested that fish remained in the discharge for considerable periods, temperature-sensitive tags indicated the majority of fish spend less than 50 hr or 10 percent of the time at discharge temperatures. During 1974 a second fish tagging study was conducted, using temperature-sensitive tags to yield discharge residence times of Lake Michigan salmonids at Point Beach thermal discharge. Preliminary results revealed that many fish tag values were close to Unit I line indicating that calculated maximum discharge residence times for these fish will be nearly 100 percent of the elapsed time

[Fifty years of residency in Psychiatry at the University of Montreal: relevance and necessity of the Residents' Association].

Science.gov (United States)

Thibault, Alexis

2015-01-01

In the context of the fiftieth anniversary celebrations of the Département de psychiatrie de l'Université de Montréal, the present article offers to retrace the history of the Psychiatry Resident's Association (ARPUM). Since the Association's activities and demands reflected the concerns of the time, a depiction of the Residency Program and exploration of the historical and administrative context, in each key period, is also undertaken. Multiple psychiatrists from every decade, who were once active members of the Association, were interviewed and asked to describe the Residency Program at their time, with its positive and negative aspects, based on their own personal experience as a resident, but also as a member of the organization. The interviewees were also invited to share their recollections of the various Association's demands, representations, activities and functioning, depending on the issues and periods. Various private and public archives were also used, in order to contextualize the residents' experiences and the Association's work. A brief exploration of the historical and political context that led to the creation of the organization is explained. Training and working conditions of residents at that time are reported, enabling the understanding of the first demands when the group was born. Historical jumps are then proposed, from decades to decades, in order to depict key issues, whether they were academic, clinical or organizational, through which the Association worked, over the evolution of the Residency Program. The internal functioning and its occasional problems throughout the years are also described, as is the role in organizing social and educational events. The Residency Program is in constant mutation, and the Association has played its part in shaping the psychiatric training at the Université de Montréal. Multiple positive and tangible impacts were and are still made possible from the collaborative work between the Département de

Changes in medicine: residency

Directory of Open Access Journals (Sweden)

Robbins RA

2011-07-01

Full Text Available No abstract available. Article truncated at 150 words. The most important time in a physician’s educational development is residency, especially the first year. However, residency work and responsibility have come under the scrutiny of a host of agencies and bureaucracies, and therefore, is rapidly changing. Most important in the alphabet soup of regulatory agencies is the Accreditation Council for Graduate Medical Education (ACGME which accredits residencies and ultimately makes the governing rules.Resident work hours have received much attention and are clearly decreasing. However, the decline in work hours began in the 1970’s before the present political push to decrease work hours. The residency I entered in 1976 had every third night call during the first year resident’s 6-9 months on general medicine or wards. It had changed from every other night the year before. On wards, we normally were in the hospital for our 24 hours of call and followed this with a 10-12 hour day before …

Measurements of liquid phase residence time distributions in a pilot-scale continuous leaching reactor using radiotracer technique

International Nuclear Information System (INIS)

Pant, H.J.; Sharma, V.K.; Shenoy, K.T.; Sreenivas, T.

2015-01-01

An alkaline based continuous leaching process is commonly used for extraction of uranium from uranium ore. The reactor in which the leaching process is carried out is called a continuous leaching reactor (CLR) and is expected to behave as a continuously stirred tank reactor (CSTR) for the liquid phase. A pilot-scale CLR used in a Technology Demonstration Pilot Plant (TDPP) was designed, installed and operated; and thus needed to be tested for its hydrodynamic behavior. A radiotracer investigation was carried out in the CLR for measurement of residence time distribution (RTD) of liquid phase with specific objectives to characterize the flow behavior of the reactor and validate its design. Bromine-82 as ammonium bromide was used as a radiotracer and about 40–60 MBq activity was used in each run. The measured RTD curves were treated and mean residence times were determined and simulated using a tanks-in-series model. The result of simulation indicated no flow abnormality and the reactor behaved as an ideal CSTR for the range of the operating conditions used in the investigation. - Highlights: • Radiotracer technique was applied for evaluation of design of a pilot-scale continuous leaching reactor. • Mean residence time and dead volume were estimated. Dead volume was found to be ranging from 4% to 15% at different operating conditions. • Tank-in-series model was used to simulate the measured RTD data and was found suitable to describe the flow in the reactor. • No flow abnormality was found and the reactor behaved as a well-mixed system. The design of the reactor was validated

The decadal state of the terrestrial carbon cycle : Global retrievals of terrestrial carbon allocation, pools, and residence times

NARCIS (Netherlands)

Bloom, A Anthony; Exbrayat, Jean-François; van der Velde, Ivar R; Feng, Liang; Williams, Mathew

2016-01-01

The terrestrial carbon cycle is currently the least constrained component of the global carbon budget. Large uncertainties stem from a poor understanding of plant carbon allocation, stocks, residence times, and carbon use efficiency. Imposing observational constraints on the terrestrial carbon cycle

Global health training in US obstetrics and gynaecology residency programmes: perspectives of students, residents and programme directors.

Science.gov (United States)

Nathan, Lisa M; Banks, Erika H; Conroy, Erin M; McGinn, Aileen P; Ghartey, Jeny P; Wagner, Sarah A; Merkatz, Irwin R

2015-12-01

Benefits of exposure to global health training during medical education are well documented and residents' demand for this training is increasing. Despite this, it is offered by few US obstetrics and gynaecology (OBGYN) residency training programmes. To evaluate interest, perceived importance, predictors of global health interest and barriers to offering global health training among prospective OBGYN residents, current OBGYN residents and US OGBYN residency directors. We designed two questionnaires using Likert scale questions to assess perceived importance of global health training. The first was distributed to current and prospective OBGYN residents interviewing at a US residency programme during 2012-2013. The second questionnaire distributed to US OBGYN programme directors assessed for existing global health programmes and global health training barriers. A composite Global Health Interest/Importance score was tabulated from the Likert scores. Multivariable linear regression was performed to assess for predictors of Global Health Interest/Importance. A total of 159 trainees (77%; 129 prospective OBGYN residents and 30 residents) and 69 (28%) programme directors completed the questionnaires. Median Global Health Interest/Importance score was 7 (IQR 4-9). Prior volunteer experience was predictive of a 5-point increase in Global Health Interest/Importance score (95% CI -0.19 to 9.85; p=0.02). The most commonly cited barriers were cost and time. Interest and perceived importance of global health training in US OBGYN residency programmes is evident among trainees and programme directors; however, significant financial and time barriers prevent many programmes from offering opportunities to their trainees. Prior volunteer experience predicts global health interest. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Successful invaders co-opt pollinators of native flora and accumulate insect pollinators with increasing residence time

Czech Academy of Sciences Publication Activity Database

Pyšek, Petr; Jarošík, Vojtěch; Chytrý, M.; Danihelka, Jiří; Kuhn, D.; Pergl, Jan; Tichý, L.; Biesmeijer, J. C.; Ellis, W. N.; Kunin, W. E.; Settele, J.

2011-01-01

Roč. 81, č. 2 (2011), s. 277-293 ISSN 0012-9615 R&D Projects: GA MŠk LC06073; GA ČR GA206/09/0563 Grant - others:European Comission(XE) GOCE-CT-2003-506675 Institutional research plan: CEZ:AV0Z60050516 Keywords : pollination * residence time * plant invasion Subject RIV: EF - Botanics Impact factor: 7.433, year: 2011

Isotopic and geochemical tracers in the evaluation of groundwater residence time and salinization problems at Santiago Island, Cape Verde

International Nuclear Information System (INIS)

Carreira, Paula M.; Nunes, Dina; Marques, Jose M.; Monteiro Santos, Fernando A.; Goncalves, Rui; Pina, Antonio; Mota Gomes, Antonio

2013-01-01

Stable isotopes (δ 18 O, δ 2 H) and tritium ( 3 H), together with geochemistry and geophysical data, were used for evaluating groundwater recharge sources, flow paths, and residence times in a watershed on Santiago Island, Cape Verde, West Africa. Stable isotopes indicate the predominance of high-elevation precipitation that undergoes little evaporation prior to groundwater recharge. Low tritium concentrations at seven sampling sites indicate groundwater residence times greater than 50 years. Higher tritium values at other locations suggest more recent recharge. Young ages indicate local recharge and potential groundwater vulnerability to surface contamination and/or salt-water intrusion. Geochemical results indicate that water-rock interaction mechanisms are the major processes responsible for the groundwater quality (mainly calcium-bicarbonate type), reflecting the lithological composition of subsurface soil. (authors)

Isotopic and geochemical tracers in the evaluation of groundwater residence time and salinization problems at Santiago Island, Cape Verde

Energy Technology Data Exchange (ETDEWEB)

Carreira, Paula M.; Nunes, Dina [Quimica Analitica e Ambiental, IST/ITN, Universidade Tecnica de Lisboa, Estrada Nacional no. 10, 2686-953 Sacavem (Portugal); Marques, Jose M. [Centro de Petrologia e Geoquimica. Instituto Superior Tecnico, UTL, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Monteiro Santos, Fernando A. [Universidade de Lisboa-IDL, 1749-016 Lisboa (Portugal); Goncalves, Rui [Inst. Politecnico de Tomar, Quinta do Contador, Estrada da Serra, 2300 Tomar (Portugal); Pina, Antonio; Mota Gomes, Antonio [Instituto Superior de Educacao, Praia, Santiago (Cape Verde)

2013-07-01

Stable isotopes (δ{sup 18}O, δ{sup 2}H) and tritium ({sup 3}H), together with geochemistry and geophysical data, were used for evaluating groundwater recharge sources, flow paths, and residence times in a watershed on Santiago Island, Cape Verde, West Africa. Stable isotopes indicate the predominance of high-elevation precipitation that undergoes little evaporation prior to groundwater recharge. Low tritium concentrations at seven sampling sites indicate groundwater residence times greater than 50 years. Higher tritium values at other locations suggest more recent recharge. Young ages indicate local recharge and potential groundwater vulnerability to surface contamination and/or salt-water intrusion. Geochemical results indicate that water-rock interaction mechanisms are the major processes responsible for the groundwater quality (mainly calcium-bicarbonate type), reflecting the lithological composition of subsurface soil. (authors)

Public opinion and resident's behaviour toward municipal solid waste plants

International Nuclear Information System (INIS)

De Feo, G.; Panza, D.; Belgiorno, V.; Napoli, R.M.A.

2006-01-01

The paper presents and discusses the results of a survey on public opinion and resident's concerns, perceptions and attitude toward MSW plants. The study was developed by means of a structured questionnaire designed on literature reviews and experiences. The study area regards four villages in a province of Naples in Campagna Region, in Southern Italy (Tufino, Comiziano, Casamarciano and Visciano). In this area there were two sanitary landfills (in their capping phase) and an RDF production plant. People in the village where MSW plants were localised, showed a 'particular' behaviour: they underestimated environmental impacts of MSW facilities. While, the results obtained from the other three villages confirmed that concerns, perceptions and attitudes towards MSW facilities are distance related [it

Family practice residents' maternity leave experiences and benefits.

Science.gov (United States)

Gjerdingen, D K; Chaloner, K M; Vanderscoff, J A

1995-09-01

A growing number of residents are having babies during residency training. While many businesses are working to improve maternity conditions and benefits for their employees, residency programs are often not prepared to accommodate pregnant residents. This study was conducted to examine the maternity leave experiences of women who delivered infants during their family practice residency training. Program directors from each of the 394 family practice residency programs listed in the 1993 Directory of Family Practice Residency Programs were asked to distribute surveys to female residents who gave birth during their residency training and had returned to work by the time of the study. Of 199 known eligible residents, 171 (86%) completed surveys; these women represented 127 programs located in 36 states and Puerto Rico. Only 56.8% of women were aware of their program having a written maternity leave policy. The average length of maternity leave was 8 weeks; 76% had leaves of 10 weeks or less. For many, the maternity leave was derived from more than one source, including vacation, sick time, or a mother-child elective. Nearly all (88.3%) the women breast-fed, and the mean duration of breast-feeding was more than 19 weeks. In general, participants believed that having a baby during residency was somewhat difficult. Problems frequently encountered by women after their return to work included sleep deprivation and tiredness, difficulty arranging for child care, guilt about child care, and breast-feeding. Factors that detracted most from the childbirth experience were too little sleep, problems arranging for child care, and lack of support from the partner, residency faculty, and other residents. Having a baby during residency is somewhat difficult for the average female resident. Factors that may ease this difficulty include getting adequate sleep and receiving support from one's partner, faculty, and other residents.

The significance of oxygen as oxides and hydroxides in controlling the abundance and residence times of elements in seawater

Digital Repository Service at National Institute of Oceanography (India)

DileepKumar, M.

A model is presented which signifies the role of oxygen (as oxides and hydroxides) in controlling the composition of seawater. respective concentration and residence times for the unknown elements can be estimated. Geometric and statistical indices...

Groundwater residence time in basement aquifers of the Ochi-Narkwa Basin in the Central Region of Ghana

Science.gov (United States)

Ganyaglo, Samuel Y.; Osae, Shiloh; Akiti, Tetteh; Armah, Thomas; Gourcy, Laurence; Vitvar, Tomas; Ito, Mari; Otoo, Isaac

2017-10-01

Groundwaters from basement aquifers in the Ochi-Narkwa basin of the Central Region together with rain and surface waters have been analysed for stable isotopes (δ18O, δ2H and δ13C) and radioisotopes (3H and 14C) to determine sources of recharge, groundwater residence time and flow path. The mechanism of recharge to the groundwaters is by direct infiltration of past local rainfall of mean isotopic composition δ18O = -3.8‰ V-SMOW and δ2H = -18‰ V-SMOW. Tritium in the groundwaters ranged from 0.05 ± 0.07 to 4.75 ± 0.16 TU. Tritium data revealed that 85% of the groundwater samples were of modern recharge or young waters. The 14C content of the groundwaters ranged between 9.50 pMC in borehole CR2-50 at Ekumfi Asokwa to 113.56 pMC in borehole CR3-26 at Onyaadze. Evaluation of 3H and 14C data distinguished three groups of water namely (1) waters characterised by high 3H and high 14C depicting modern recharge, (2) waters showing a mixture of young and old water due to fractures and (3) waters showing low 3H and low 14C contents referred to as very old waters and include borehole CR2-50 at Ekumfi Asokwa. The estimated age or residence time of this older water is 19,459 years BP based on uncorrected age. The major flow direction is northwest-southeast. The dominant months contributing to recharge in the study area were February, March, April, May, June, August, September and October. Groundwater residence times in the basement aquifers of the Ochi-Narkwa basin showed that groundwater abstraction is sustainable and requires that the recharge areas are protected from contamination.

E-Learning and Medical Residents, a Qualitative Perspective

Science.gov (United States)

Segerman, Jill; Crable, Elaine; Brodzinski, James

2016-01-01

Medical education helps ensure doctors acquire skills and knowledge needed to care for patients. However, resident duty hour restrictions have impacted the time residents have available for medical education, leaving resident educators searching for alternate options for effective medical education. Classroom situated e-learning, a blended…

U Isotope Systematics on Groundwaters from Southwestern France : Mixing Processes and Residence Times

Science.gov (United States)

Innocent, C.; Malcuit, E.; Négrel, P.

2011-12-01

The Eocene Sands Aquifer of the Aquitanian Basin (Southwestern France) has been extensively studied for its hydrology, hydrogeochemistry and also for stable isotopes (André, 2002; André et al., 2005). 14C dates were also obtained in the southern part of the aquifer (André, 2002). Recently, in the framework of the CARISMEAU research project (Négrel et al., 2007), groundwaters have been analyzed for their U activity ratio in order to put some constraints on their residence time in the aquifer. A excellent correlation has been found between 234U/238U ratios (which can be as high as 13.5) and 14C dates, which allowed to propose residence times for the analyzed groundwaters at the scale of the whole aquifer (including the city of Bordeaux and its suburb) (Innocent and Négrel, 2008; submitted). The second step of the CARISMEAU research project (CARISMEAU 2) now focusses on the restricted "Entre-Deux-Mers" area. New groundwaters have been recovered and analyzed for their U isotopic composition. As for previous data, U activity ratios are typically very high, ranging from 2.9 to 8.6. Owing to additional 14C ages from the northern part of the aquifer, it is shown that most of the measured uranium activity ratios correlate with these 14C dates and fall on or close to the straight line defined previously (see above). As a consequence, residence times derived from U isotopic compositions fairly agree with 14C data, with only one exception from a groundwater which plots apart from the correlation line. Pumping tests have been done at a selected site (EMZM 7), involving pumping times of 1 hour, 8 hours and 16 hours. For each pumping time, waters have been recovered at different, increasing pumping rates of 80 m3 per hour, 120 m3 per hour, 160 m3 per hour, and 120 m3 per hour. The chemical composition of these twelve waters has not been found to vary significantly. Uranium activities are constant for ten of the twelve groundwaters (around 6.5, with a U concentration around

Residence times and mixing of water in river banks: implications for recharge and groundwater - surface water exchange

Science.gov (United States)

Unland, N. P.; Cartwright, I.; Cendón, D. I.; Chisari, R.

2014-02-01

The residence time of groundwater within 50 m of the Tambo River, South East Australia, has been estimated through the combined use of 3H and 14C. Groundwater residence times increase towards the Tambo River which implies a gaining river system and not increasing bank storage with proximity to the Tambo River. Major ion concentrations and δ2H and δ18O values of bank water also indicate that bank infiltration does not significantly impact groundwater chemistry under baseflow and post-flood conditions, suggesting that the gaining nature of the river may be driving the return of bank storage water back into the Tambo River within days of peak flood conditions. The covariance between 3H and 14C indicates the leakage and mixing between old (~17 200 yr) groundwater from a semi-confined aquifer and younger groundwater (bank storage, as rapid pressure propagation into the semi-confined aquifer during flooding will minimise bank infiltration. This study illustrates the complex nature of river groundwater interactions and the potential downfall in assuming simple or idealised conditions when conducting hydrogeological studies.

Alternatives for the treatment of the organic fraction of the urban solid residuals

International Nuclear Information System (INIS)

Benitez Fonseca, Mabelin; Fernandez Mena, Dalia; Abalos Rodriguez, Arelis; Rodriguez Perez, Suyen

2011-01-01

The decomposition of municipal solid waste outdoors, or in some cases burning under the same conditions, is action now and final disposition of these wastes without measuring their consequences. In the student's residence 'Antonio Maceo' Orient University is hosting up to 2250 students belonging to a total of 22 university, generating at full capacity, 3375 kg / day of MSW. This research aims to analyze the solid waste generated in the student's residence, where improperly evaluated the final disposition thereof. It was found that discharges are not separated at the source observed at the landfill, food waste, sweeping waste, paper and cardboard, plastics, glass, metal, textile waste, wood, etc. Samplings were carried out directly in 12 rooms of the residence for a total of 48 people, along with students, as part of the educational activities implemented within this work. The average weight of degradable waste generated was 2.5 kg / day during the sampling, revealing the presence of traces of cooked food (cereals, legumes, carbohydrates), fruit and vegetable remains, remains of shells of different origins ( meats, eggs), remnants of tea, etc. The average content of total solids in the waste sampled was 36.3 ± 5.4% and volatile solids content on dry weight was 81.3 ± 2.5% to an average density of 0.68 g / cm3. This residue is characterized to be treated in an anaerobic batch reactor where it is recirculated leachate and studied the competing microorganisms in the anaerobic degradation of organic fraction of municipal solid waste. (author)

Measurement of residence time distribution of liquid phase in an industrial-scale continuous pulp digester using radiotracer technique.

Science.gov (United States)

Sheoran, Meenakshi; Goswami, Sunil; Pant, Harish J; Biswal, Jayashree; Sharma, Vijay K; Chandra, Avinash; Bhunia, Haripada; Bajpai, Pramod K; Rao, S Madhukar; Dash, A

2016-05-01

A series of radiotracer experiments was carried out to measure residence time distribution (RTD) of liquid phase (alkali) in an industrial-scale continuous pulp digester in a paper industry in India. Bromine-82 as ammonium bromide was used as a radiotracer. Experiments were carried out at different biomass and white liquor flow rates. The measured RTD data were treated and mean residence times in individual digester tubes as well in the whole digester were determined. The RTD was also analyzed to identify flow abnormalities and investigate flow dynamics of the liquid phase in the pulp digester. Flow channeling was observed in the first section (tube 1) of the digester. Both axial dispersion and tanks-in-series with backmixing models preceded with a plug flow component were used to simulate the measured RTD and quantify the degree of axial mixing. Based on the study, optimum conditions for operating the digester were proposed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Latitude of residence and position in time zone are predictors of cancer incidence, cancer mortality, and life expectancy at birth.

Science.gov (United States)

Borisenkov, Mikhail F

2011-03-01

According to the hypothesis of circadian disruption, external factors that disturb the function of the circadian system can raise the risk of malignant neoplasm and reduce life span. Recent work has shown that the functionality of the circadian system is dependent not only on latitude of residence but also on the region's position in the time zone. The purpose of the present research was to examine the influence of latitude and time zone on cancer incidence, cancer mortality, and life expectancy at birth. A stepwise multiple regression analysis was carried out on residents of 59 regions of the European part of the Russian Federation (EPRF) using age-standardized parameters (per 100,000) of cancer incidence (CI), cancer mortality (CM), and life expectancy at birth (LE, yrs) as dependent variables. The geographical coordinates (latitude and position in the time zone) of the regions were used as independent variables, controlling for the level of economic development in the regions. The same analysis was carried out for LE in 31 regions in China. Latitude was the strongest predictor of LE in the EPRF population; it explained 48% and 45% of the variability in LE of women and men, respectively. Position within the time zone accounted for an additional 4% and 3% variability of LE in women and men, respectively. The highest values for LE were observed in the southeast of the EPRF. In China, latitude was not a predictor of LE, whereas position in the time zone explained 15% and 18% of the LE variability in women and men, respectively. The highest values of LE were observed in the eastern regions of China. Both latitude and position within the time zone were predictors for CI and CM of the EPRF population. Latitude was the best predictor of stomach CI and CM; this predictor explained 46% and 50% of the variability, respectively. Position within the time zone was the best predictor of female breast CM; it explained 15% of the variability. In most cases, CI and CM increased

Flow Mapping in a Gas-Solid Riser via Computer Automated Radioactive Particle Tracking (CARPT)

Energy Technology Data Exchange (ETDEWEB)

Muthanna Al-Dahhan; Milorad P. Dudukovic; Satish Bhusarapu; Timothy J. O' hern; Steven Trujillo; Michael R. Prairie

2005-06-04

Statement of the Problem: Developing and disseminating a general and experimentally validated model for turbulent multiphase fluid dynamics suitable for engineering design purposes in industrial scale applications of riser reactors and pneumatic conveying, require collecting reliable data on solids trajectories, velocities ? averaged and instantaneous, solids holdup distribution and solids fluxes in the riser as a function of operating conditions. Such data are currently not available on the same system. Multiphase Fluid Dynamics Research Consortium (MFDRC) was established to address these issues on a chosen example of circulating fluidized bed (CFB) reactor, which is widely used in petroleum and chemical industry including coal combustion. This project addresses the problem of lacking reliable data to advance CFB technology. Project Objectives: The objective of this project is to advance the understanding of the solids flow pattern and mixing in a well-developed flow region of a gas-solid riser, operated at different gas flow rates and solids loading using the state-of-the-art non-intrusive measurements. This work creates an insight and reliable database for local solids fluid-dynamic quantities in a pilot-plant scale CFB, which can then be used to validate/develop phenomenological models for the riser. This study also attempts to provide benchmark data for validation of Computational Fluid Dynamic (CFD) codes and their current closures. Technical Approach: Non-Invasive Computer Automated Radioactive Particle Tracking (CARPT) technique provides complete Eulerian solids flow field (time average velocity map and various turbulence parameters such as the Reynolds stresses, turbulent kinetic energy, and eddy diffusivities). It also gives directly the Lagrangian information of solids flow and yields the true solids residence time distribution (RTD). Another radiation based technique, Computed Tomography (CT) yields detailed time averaged local holdup profiles at

Groundwater residence times in Shenandoah National Park, Blue Ridge Mountains, Virginia, USA: A multi-tracer approach

Science.gov (United States)

Plummer, Niel; Busenberg, E.; Böhlke, J.K.; Nelms, D.L.; Michel, R.L.; Schlosser, P.

2001-01-01

Chemical and isotopic properties of water discharging from springs and wells in Shenandoah National Park (SNP), near the crest of the Blue Ridge Mountains, VA, USA were monitored to obtain information on groundwater residence times. Investigated time scales included seasonal (wet season, April, 1996; dry season, August–September, 1997), monthly (March through September, 1999) and hourly (30-min interval recording of specific conductance and temperature, March, 1999 through February, 2000). Multiple environmental tracers, including tritium/helium-3 (3H/3He), chlorofluorocarbons (CFCs), sulfur hexafluoride (SF6), sulfur-35 (35S), and stable isotopes (δ18O and δ2H) of water, were used to estimate the residence times of shallow groundwater discharging from 34 springs and 15 wells. The most reliable ages of water from springs appear to be based on SF6 and 3H/3He, with most ages in the range of 0–3 years. This range is consistent with apparent ages estimated from concentrations of CFCs; however, CFC-based ages have large uncertainties owing to the post-1995 leveling-off of the CFC atmospheric growth curves. Somewhat higher apparent ages are indicated by 35S (>1.5 years) and seasonal variation of δ18O (mean residence time of 5 years) for spring discharge. The higher ages indicated by the 35S and δ18O data reflect travel times through the unsaturated zone and, in the case of 35S, possible sorption and exchange of S with soils or biomass. In springs sampled in April, 1996, apparent ages derived from the 3H/3He data (median age of 0.2 years) are lower than those obtained from SF6 (median age of 4.3 years), and in contrast to median ages from 3H/3He (0.3 years) and SF6 (0.7 years) obtained during the late summer dry season of 1997. Monthly samples from 1999 at four springs in SNP had SF6apparent ages of only 1.2 to 2.5±0.8 years, and were consistent with the 1997 SF6 data. Water from springs has low excess air (0–1 cm3 kg−1) and N2–Ar temperatures that vary

A study of residence time distribution using radiotracer technique in the large scale plant facility

Science.gov (United States)

Wetchagarun, S.; Tippayakul, C.; Petchrak, A.; Sukrod, K.; Khoonkamjorn, P.

2017-06-01

As the demand for troubleshooting of large industrial plants increases, radiotracer techniques, which have capability to provide fast, online and effective detections to plant problems, have been continually developed. One of the good potential applications of the radiotracer for troubleshooting in a process plant is the analysis of Residence Time Distribution (RTD). In this paper, the study of RTD in a large scale plant facility using radiotracer technique was presented. The objective of this work is to gain experience on the RTD analysis using radiotracer technique in a “larger than laboratory” scale plant setup which can be comparable to the real industrial application. The experiment was carried out at the sedimentation tank in the water treatment facility of Thailand Institute of Nuclear Technology (Public Organization). Br-82 was selected to use in this work due to its chemical property, its suitable half-life and its on-site availability. NH4Br in the form of aqueous solution was injected into the system as the radiotracer. Six NaI detectors were placed along the pipelines and at the tank in order to determine the RTD of the system. The RTD and the Mean Residence Time (MRT) of the tank was analysed and calculated from the measured data. The experience and knowledge attained from this study is important for extending this technique to be applied to industrial facilities in the future.

77 FR 17410 - Solid Urea From the Russian Federation: Extension of Time Limit for Preliminary Results of...

Science.gov (United States)

2012-03-26

... DEPARTMENT OF COMMERCE International Trade Administration [A-821-801] Solid Urea From the Russian Federation: Extension of Time Limit for Preliminary Results of Antidumping Duty Administrative Review AGENCY... Commerce (the Department) initiated an administrative review of the antidumping duty order on solid urea...

The pregnant female surgical resident

Directory of Open Access Journals (Sweden)

Shifflette V

2018-05-01

Full Text Available Vanessa Shifflette,1 Susannah Hambright,2 Joseph Darryl Amos,1 Ernest Dunn,3 Maria Allo4 1Associates in Surgical Acute Care, Methodist Dallas Medical Center, Dallas, TX, USA; 2Methodist Surgical Associates, Methodist Dallas Medical Center, Dallas, TX, USA; 3Graduate Medical Education - General Surgery, Methodist Dallas Medical Center, Dallas, TX, USA; 4Santa Clara Valley Medical Center, San Jose, CA, USA Background: Surgery continues to be an intense, time-consuming residency. Many medical students decide against surgery as a profession due to the long work hours and family strain. The pregnant female surgical resident has an added stress factor compared to her male counterpart. Methods: We distributed an electronic, online 26-question survey to 32 general surgery programs in the southwestern region of the United States. Each program distributed our survey to the female surgical residents who had been pregnant during residency in the last 5 years. Each program was re-contacted 6 weeks after the initial contact. Most questions were in a 5-point Likert scale format. The responses were collected and analyzed using the Survey Monkey website. Results: An unvalidated survey was sent to 32 general surgery programs and 26 programs responded (81%. Each program was asked for the total number of possible responses from female residents that met our criteria (60 female residents. Seven of the programs (27% stated that they have had zero residents pregnant. We had 22 residents respond (37%. Over half of the residents (55% were pregnant during their 2nd or 3rd year of residency, with only 18% pregnant during a research year. Thirty-one percent had a lower American Board of Surgery In-Training Exam (ABSITE score. Ninety percent of the residents were able to take 4 weeks or more for maternity leave. Most of the residents (95% stated that they would do this again during residency given the opportunity, but many of the residents felt that returning back to work

Resident fatigue in otolaryngology residents: a Web based survey.

Science.gov (United States)

Nida, Andrew M; Googe, Benjamin J; Lewis, Andrea F; May, Warren L

2016-01-01

Resident fatigue has become a point of emphasis in medical education and its effects on otolaryngology residents and their patients require further study. The purpose of our study was to evaluate the prevalence and nature of fatigue in otolaryngology residents, evaluate various quality of life measures, and investigate associations of increased fatigue with resident safety. Anonymous survey. Internet based. United States allopathic otolaryngology residents. None. The survey topics included demographics, residency structure, sleep habits and perceived stress. Responses were correlated with a concurrent Epworth Sleep Scale questionnaire to evaluate effects of fatigue on resident training and quality of life. 190 residents responded to the survey with 178 completing the Epworth Sleep Scale questionnaire. Results revealed a mean Epworth Sleep Scale score of 9.9±5.1 with a median of 10.0 indicating a significant number of otolaryngology residents are excessively sleepy. Statistically significant correlations between Epworth Sleep Scale and sex, region, hours of sleep, and work hours were found. Residents taking in-house call had significantly fewer hours of sleep compared to home call (p=0.01). Residents on "head and neck" (typically consisting of a large proportion of head and neck oncologic surgery) rotations tended to have higher Epworth Sleep Scale and had significantly fewer hours of sleep (p=.003) and greater work hours (potolaryngology residents are excessively sleepy. Our data suggest that the effects of fatigue play a role in resident well-being and resident safety. Copyright © 2016 Elsevier Inc. All rights reserved.

Maternity leave: existing policies in obstetrics and gynecology residency programs.

Science.gov (United States)

Davis, J L; Baillie, S; Hodgson, C S; Vontver, L; Platt, L D

2001-12-01

To survey program directors in obstetrics and gynecology regarding maternity leave and to determine how programs are dealing with maternity leave coverage. Questionnaires regarding impact and policy on maternity leave were mailed to accredited obstetrics and gynecology residency programs. A total of 188 of 274 (69%) questionnaires were returned completed. Respectively, 80% and 69% of respondents indicated that they have a formal maternity (maximum mean 8.7 weeks) and paternity (mean 5.27 days) leave policy. Approximately 75% of programs require residents to make up time if their leave exceeds 8 weeks during the first 3 years. Eighty-five percent of programs require residents to make up time if their leave exceeds 6 weeks during the fourth year. Ninety-three percent of programs require residents to make up time if their leave exceeds 20 weeks over the 4 years. Seventy-seven percent of respondents have other residents in their program cover for the absent resident. Thirty-seven percent of programs have schedules flexible enough to allow rearrangement so that some rotations go uncovered. Eighty-three percent of programs surveyed stated that maternity leave has a somewhat to very significant impact on the residents' schedules. Most residency programs have written maternity/paternity leave policies. A more flexible curriculum may help to accommodate the residents on leave without overburdening the residents who are left to cover.

Association of General Surgery Resident Remediation and Program Director Attitudes With Resident Attrition.

Science.gov (United States)

Schwed, Alexander C; Lee, Steven L; Salcedo, Edgardo S; Reeves, Mark E; Inaba, Kenji; Sidwell, Richard A; Amersi, Farin; Are, Chandrakanth; Arnell, Tracey D; Damewood, Richard B; Dent, Daniel L; Donahue, Timothy; Gauvin, Jeffrey; Hartranft, Thomas; Jacobsen, Garth R; Jarman, Benjamin T; Melcher, Marc L; Mellinger, John D; Morris, Jon B; Nehler, Mark; Smith, Brian R; Wolfe, Mary; Kaji, Amy H; de Virgilio, Christian

2017-12-01

Previous studies of resident attrition have variably included preliminary residents and likely overestimated categorical resident attrition. Whether program director attitudes affect attrition has been unclear. To determine whether program director attitudes are associated with resident attrition and to measure the categorical resident attrition rate. This multicenter study surveyed 21 US program directors in general surgery about their opinions regarding resident education and attrition. Data on total resident complement, demographic information, and annual attrition were collected from the program directors for the study period of July 1, 2010, to June 30, 2015. The general surgery programs were chosen on the basis of their geographic location, previous collaboration with some coauthors, prior work in surgical education and research, or a program director willing to participate. Only categorical surgical residents were included in the study; thus, program directors were specifically instructed to exclude any preliminary residents in their responses. Five-year attrition rates (2010-2011 to 2014-2015 academic years) as well as first-time pass rates on the General Surgery Qualifying Examination and General Surgery Certifying Examination of the American Board of Surgery (ABS) were collected. High- and low-attrition programs were compared. The 21 programs represented different geographic locations and 12 university-based, 3 university-affiliated, and 6 independent program types. Programs had a median (interquartile range [IQR]) number of 30 (20-48) categorical residents, and few of those residents were women (median [IQR], 12 [5-17]). Overall, 85 of 966 residents (8.8%) left training during the study period: 15 (17.6%) left after postgraduate year 1, 34 (40.0%) after postgraduate year 2, and 36 (42.4%) after postgraduate year 3 or later. Forty-four residents (51.8%) left general surgery for another surgical discipline, 21 (24.7%) transferred to a different surgery

The Effect of Beaver Activity on the Ammonium Uptake and Water Residence Time Characteristics of a Third-Order Stream Reach

Science.gov (United States)

Briggs, M.; Gooseff, M. N.; Wollheim, W. M.; Peterson, B. J.; Morkeski, K.

2009-12-01

Increasing beaver populations within low gradient basins in the northeastern United States are fundamentally changing the way water and dissolved nutrients are exported through these stream networks to the coast. Beaver dams can increase water residence time and contact with organic material, promote anoxic conditions and enhance both surface and hyporheic transient storage; all of these may have an impact on biogeochemical reactivity and nutrient retention. To quantitatively assess some of these effects we co-injected NaCl and NH4+ into the same 3rd-order stream reach in Massachusetts, USA under pre- and post-dam conditions. These experiments were done at similar discharge rates to isolate the impacts of a large natural beaver dam (7 m X 1.3 m) on the low-gradient (0.002) system where variable discharge also imparts a strong control on residence time. During the post-dam experiment there was an estimated 2300 m3 of water impounded behind the structure, which influenced more than 300 m of the 650 m stream reach. Our results showed that median transport time through the reach increased by 160% after dam construction. Additionally the tracer tailing time normalized to the corresponding median transport time increased from 1.08 to 1.51, indicating a pronounced tailing of the tracer signal in the post-dam condition. Data collected within the beaver pond just upstream of the dam indicated poor mixing and the presence of preferential flow paths through the generally stagnant zone. The uptake length (Sw) for NH4+ was 1250 m under the pre-dam condition, and may have changed for the post-dam reach in part because of the observed changes in residence time. As beaver population growth continues within these basins the consequences may be a smoothing of the outlet hydrograph and increased nutrient and organic matter removal and storage along the stream network.

76 FR 17380 - Solid Urea From the Russian Federation: Extension of Time Limit for Preliminary Results of...

Science.gov (United States)

2011-03-29

... DEPARTMENT OF COMMERCE International Trade Administration [A-821-801] Solid Urea From the Russian Federation: Extension of Time Limit for Preliminary Results of Antidumping Duty Administrative Review AGENCY... administrative review of the antidumping duty order on solid urea from the Russian Federation for the period July...

Preliminary estimates of residence times and apparent ages of ground water in the Chesapeake Bay watershed, and water-quality data from a survey of springs

Science.gov (United States)

Focazio, Michael J.; Plummer, Niel; Bohlke, John K.; Busenberg, Eurybiades; Bachman, L. Joseph; Powars, David S.

1998-01-01

Knowledge of the residence times of the ground-water systems in Chesapeake Bay watershed helps resource managers anticipate potential delays between implementation of land-management practices and any improve-ments in river and estuary water quality. This report presents preliminary estimates of ground-water residence times and apparent ages of water in the shallow aquifers of the Chesapeake Bay watershed. A simple reservoir model, published data, and analyses of spring water were used to estimate residence times and apparent ages of ground-water discharge. Ranges of aquifer hydraulic characteristics throughout the Bay watershed were derived from published literature and were used to estimate ground-water residence times on the basis of a simple reservoir model. Simple combinations of rock type and physiographic province were used to delineate hydrogeomorphic regions (HGMR?s) for the study area. The HGMR?s are used to facilitate organization and display of the data and analyses. Illustrations depicting the relation of aquifer characteristics and associated residence times as a continuum for each HGMR were developed. In this way, the natural variation of aquifer characteristics can be seen graphically by use of data from selected representative studies. Water samples collected in September and November 1996, from 46 springs throughout the watershed were analyzed for chlorofluorocarbons (CFC?s) to estimate the apparent age of ground water. For comparison purposes, apparent ages of water from springs were calculated assuming piston flow. Additi-onal data are given to estimate apparent ages assuming an exponential distribution of ages in spring discharge. Additionally, results from previous studies of CFC-dating of ground water from other springs and wells in the watershed were compiled. The CFC data, and the data on major ions, nutrients, and nitrogen isotopes in the water collected from the 46 springs are included in this report. The apparent ages of water

Residence time of contaminants released in surface coal mines -- a wind-tunnel study

Energy Technology Data Exchange (ETDEWEB)

Thompson, R.S. [Environmental Protection Agency, Research Triangle Park, NC (United States)

1994-12-31

Surface coal mining operations (blasting, shoveling, loading, trucking, etc.) are sources of airborne particles. The 1990 Clean Air Act Amendments direct the EPA to analyze the accuracy of the Industrial Source Complex model and the AP-42 emission factors, and to make revisions as may be necessary to eliminate any significant over-prediction of air concentration of fugitive particles from surface coal mines. A wind-tunnel study was performed at the US EPA`s Fluid Modeling Facility to investigate dispersion from surface coal mines in support of the dispersion modeling activities. Described here is the portion of the study directed at determining the residence time that material released near the floor of a mine will stay within the mine.

Numerical and machine learning simulation of parametric distributions of groundwater residence time in streams and wells

Science.gov (United States)

Starn, J. J.; Belitz, K.; Carlson, C.

2017-12-01

Groundwater residence-time distributions (RTDs) are critical for assessing susceptibility of water resources to contamination. This novel approach for estimating regional RTDs was to first simulate groundwater flow using existing regional digital data sets in 13 intermediate size watersheds (each an average of 7,000 square kilometers) that are representative of a wide range of glacial systems. RTDs were simulated with particle tracking. We refer to these models as "general models" because they are based on regional, as opposed to site-specific, digital data. Parametric RTDs were created from particle RTDs by fitting 1- and 2-component Weibull, gamma, and inverse Gaussian distributions, thus reducing a large number of particle travel times to 3 to 7 parameters (shape, location, and scale for each component plus a mixing fraction) for each modeled area. The scale parameter of these distributions is related to the mean exponential age; the shape parameter controls departure from the ideal exponential distribution and is partly a function of interaction with bedrock and with drainage density. Given the flexible shape and mathematical similarity of these distributions, any of them are potentially a good fit to particle RTDs. The 1-component gamma distribution provided a good fit to basin-wide particle RTDs. RTDs at monitoring wells and streams often have more complicated shapes than basin-wide RTDs, caused in part by heterogeneity in the model, and generally require 2-component distributions. A machine learning model was trained on the RTD parameters using features derived from regionally available watershed characteristics such as recharge rate, material thickness, and stream density. RTDs appeared to vary systematically across the landscape in relation to watershed features. This relation was used to produce maps of useful metrics with respect to risk-based thresholds, such as the time to first exceedance, time to maximum concentration, time above the threshold

Child temperament and paternal transition to non-residence.

Science.gov (United States)

Flouri, Eirini; Malmberg, Lars-Erik

2010-12-01

Using the Millennium Cohort Study data this study showed that, even after adjustment, resident biological fathers of high-regularity children at 9 months were less likely than resident biological fathers of low-regularity children at 9 months to become non-resident by the time these children were 3 years old. Copyright © 2010 Elsevier Inc. All rights reserved.

Pregnancy and Parenthood among Surgery Residents: Results of the First Nationwide Survey of General Surgery Residency Program Directors.

Science.gov (United States)

Sandler, Britt J; Tackett, John J; Longo, Walter E; Yoo, Peter S

2016-06-01

Although family and lifestyle are known to be important factors for medical students choosing a specialty, there is a lack of research about general surgery residency program policies regarding pregnancy and parenthood. Similarly, little is known about program director attitudes about these issues. We performed a cross-sectional survey of United States (US) general surgery residency program directors. Sixty-six respondents completed the survey: 70% male, 59% from university-based programs, and 76% between 40 and 59 years of age. Two-thirds (67%) reported having a maternity leave policy. Less than half (48%) reported having a leave policy for the non-childbearing parent (paternity leave). Leave duration was most frequently reported as 6 weeks for maternity leave (58%) and 1 week for paternity leave (45%). Thirty-eight percent of general surgery residency program directors (PDs) reported availability of on-site childcare, 58% reported availability of lactation facilities. Forty-six percent of university PDs said that the research years are the best time to have a child during residency; 52% of independent PDs said that no particular time during residency is best. Sixty-one percent of PDs reported that becoming a parent negatively affects female trainees' work, including placing an increased burden on fellow residents (33%). Respondents perceived children as decreasing female trainees' well-being more often than male trainees' (32% vs 9%, p leave, length of leave, as well as inconsistency in access to childcare and availability of spaces to express and store breast milk. Program directors perceived parenthood to affect the training and well-being of female residents more adversely than that of male residents. Copyright © 2016 American College of Surgeons. All rights reserved.

Mixed messages: residents' experiences learning cross-cultural care.

Science.gov (United States)

Park, Elyse R; Betancourt, Joseph R; Kim, Minah K; Maina, Angela W; Blumenthal, David; Weissman, Joel S

2005-09-01

An Institute of Medicine report issued in 2002 cited cross-cultural training as a mechanism to address racial and ethnic disparities in health care, but little is known about residents' training and capabilities to provide quality care to diverse populations. This article explores a select group of residents' perceptions of their preparedness to deliver quality care to diverse populations. Seven focus groups and ten individual interviews were conducted with 68 residents in locations nationwide. Qualitative analysis of focus-group and individual interview transcripts was performed to assess residents' perceptions of (1) preparedness to deliver care to diverse patients; (2) educational climate; and (3) training experiences. Most residents in this study noted the importance of cross-cultural care yet reported little formal training in this area. Residents wanted more formal training yet expressed concern that culture-specific training could lead to stereotyping. Most residents had developed ad hoc, informal skills to care for diverse patients. Although residents perceived institutional endorsement, they sensed it was a low priority due to lack of time and resources. Residents in this study reported receiving mixed messages about cross-cultural care. They were told it is important, yet they received little formal training and did not have time to treat diverse patients in a culturally sensitive manner. As a result, many developed coping behaviors rather than skills based on formally taught best practices. Training environments need to increase training to enhance residents' preparedness to deliver high-quality cross-cultural care if the medical profession is to achieve the goals set by the Institute of Medicine.

Thermal discharge residence by Lake Michigan Salmonids

International Nuclear Information System (INIS)

Romberg, G.P.; Prepejchal, W.

1975-01-01

Lake Michigan salmon and trout were tagged with a thermoluminescent dosimeter (TLD) temperature tag to estimate their thermal exposure and residence time at a warm water discharge. Fish were collected, tagged, and released at the Point Beach Nuclear Plant, Two Rivers, Wisconsin, in the fall of 1973 and 1974. Tags were recovered during the same season, primarily from fish recaptured at Point Beach. Average uniform temperature exposure and maximum possible discharge residence time were determined. Appropriate hourly intake and discharge temperatures were averaged to calculate mean temperature exposure for the case of maximum discharge residence. Lowest discharge temperature not included within the period of maximum residence was identified to serve as a possible indicator of avoidance temperature. Mean values for the above parameters were calculated for fish species for each tagging year and are reported with the accompanying range of intake and discharge temperatures

Report: Searching for a way to sustainability: technical and policy analyses of solid waste issues in Kathmandu.

Science.gov (United States)

Dangi, Mohan B; Cohen, Ronald R H; Urynowicz, Michael A; Poudyal, Khem N

2009-05-01

Kathmandu Metropolitan City has attempted to reorganize its solid waste management a number of times. The German Technical and Financial Aid Organization led early efforts that were followed by a number of more recent experiments that left the city with an unsustainable solid waste management system following the termination of foreign aid. To examine this failure, the research team evaluated household surveys, field observations, interviews, and other primary and secondary information within the context of technical, social, and institutional analyses. The survey results show that the solid waste collection rates are far below the 90% claimed by the metropolis and street sweeping consumes approximately 51% of its solid waste budget. As a result of the relatively low collection rates the city residents are encouraged to dump waste into public lands. Consequently, too much of the city's resources are focused on sweeping rather than collection. Kathmandu needs to recognize informal waste picking, privatize, use local techniques, build capacity, promote bottom-up and participatory styles of management, and regulate policies to maintain solid waste management.

Measurements of liquid phase residence time distributions in a pilot-scale continuous leaching reactor using radiotracer technique.

Science.gov (United States)

Pant, H J; Sharma, V K; Shenoy, K T; Sreenivas, T

2015-03-01

An alkaline based continuous leaching process is commonly used for extraction of uranium from uranium ore. The reactor in which the leaching process is carried out is called a continuous leaching reactor (CLR) and is expected to behave as a continuously stirred tank reactor (CSTR) for the liquid phase. A pilot-scale CLR used in a Technology Demonstration Pilot Plant (TDPP) was designed, installed and operated; and thus needed to be tested for its hydrodynamic behavior. A radiotracer investigation was carried out in the CLR for measurement of residence time distribution (RTD) of liquid phase with specific objectives to characterize the flow behavior of the reactor and validate its design. Bromine-82 as ammonium bromide was used as a radiotracer and about 40-60MBq activity was used in each run. The measured RTD curves were treated and mean residence times were determined and simulated using a tanks-in-series model. The result of simulation indicated no flow abnormality and the reactor behaved as an ideal CSTR for the range of the operating conditions used in the investigation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Impact of adding additional providers to resident workload and the resident experience on a medical consultation rotation.

Science.gov (United States)

Fang, Michele; Linson, Eric; Suneja, Manish; Kuperman, Ethan F

2017-02-22

Excellence in Graduate Medical Education requires the right clinical environment with an appropriate workload where residents have enough patients to gain proficiency in medicine with optimal time for reflection. The Accreditation Council for Graduate Medical Education (ACGME) has focused more on work hours rather than workload; however, high resident workload has been associated with lower resident participation in education and fatigue-related errors. Recognizing the potential risks associated with high resident workload and being mindful of the costs of reducing resident workload, we sought to reduce residents' workload by adding an advanced practice provider (APP) to the surgical comanagement service (SCM) and study its effect on resident satisfaction and perceived educational value of the rotation. In Fiscal Year (FY) 2014 and 2015, an additional faculty member was added to the SCM rotation. In FY 2014, the faculty member was a staff physician, and in FY 2015, the faculty member was an APP.. Resident workload was assessed using billing data. We measured residents' perceptions of the rotation using an anonymous electronic survey tool. We compared FY2014-2015 data to the baseline FY2013. The number of patients seen per resident per day decreased from 8.0(SD 3.3) in FY2013 to 5.0(SD 1.9) in FY2014 (p value of the rotation (40.0%, 72.2%, 72.6% in FY2013, 2014, 2015 respectively, p perceived educational value and clinical experience of a medical consultation rotation.

Mixed reality ventriculostomy simulation: experience in neurosurgical residency.

Science.gov (United States)

Hooten, Kristopher G; Lister, J Richard; Lombard, Gwen; Lizdas, David E; Lampotang, Samsun; Rajon, Didier A; Bova, Frank; Murad, Gregory J A

2014-12-01

Medicine and surgery are turning toward simulation to improve on limited patient interaction during residency training. Many simulators today use virtual reality with augmented haptic feedback with little to no physical elements. In a collaborative effort, the University of Florida Department of Neurosurgery and the Center for Safety, Simulation & Advanced Learning Technologies created a novel "mixed" physical and virtual simulator to mimic the ventriculostomy procedure. The simulator contains all the physical components encountered for the procedure with superimposed 3-D virtual elements for the neuroanatomical structures. To introduce the ventriculostomy simulator and its validation as a necessary training tool in neurosurgical residency. We tested the simulator in more than 260 residents. An algorithm combining time and accuracy was used to grade performance. Voluntary postperformance surveys were used to evaluate the experience. Results demonstrate that more experienced residents have statistically significant better scores and completed the procedure in less time than inexperienced residents. Survey results revealed that most residents agreed that practice on the simulator would help with future ventriculostomies. This mixed reality simulator provides a real-life experience, and will be an instrumental tool in training the next generation of neurosurgeons. We have now implemented a standard where incoming residents must prove efficiency and skill on the simulator before their first interaction with a patient.

Early-time particle dynamics and non-affine deformations during microstructure selection in solids

Energy Technology Data Exchange (ETDEWEB)

Sengupta, Surajit [Centre for Advanced Materials, Indian Association for the Cultivation of Science, 2A and 2B, Raja S C Mullick Road, Jadavpur, Kolkata 700032 (India); Rao, Madan [Raman Research Institute, C V Raman Avenue, Bangalore 560 080 (India); Bhattacharya, Jayee [S N Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700 098 (India)

2011-07-27

Solid-solid transitions are invariably associated with groups of particles whose deformations cannot be expressed as an affine strain about a reference configuration. The dynamics of these non-affine zones (NAZ) determine the subsequent microstructure, i.e. the mesoscale patterning resulting from the structural transition. Here, we focus on early-time dynamics of individual particles within an NAZ associated with a nucleation event. We show that the early-time behavior of these particles have distinctive characteristics depending on the transition temperature. The dynamics is heterogeneous, consisting of a few active particles exhibiting complex intermittent jamming and flow in response to internal stresses generated during the transformation. At low temperatures, the dynamics of these active particles is ballistic and the structural transformation proceeds via string-like correlated movement of active particles, along ridges in the potential energy topography set up by inactive particles. On increasing temperature, the dynamics of active particles show an abrupt transition from ballistic to diffusive behavior with a diffusion coefficient which appears to be independent of temperature. This dynamical transition in the nature of the trajectories of particles is coincident with a discontinuous transition in the microstructure of the solid. Finally, we characterize this transition in terms of a dynamical order parameter in the space of trajectories and discuss its connection with the glass transition and rheology of soft and granular matter.

Organizational and Individual Conditions Associated with Depressive Symptoms among Nursing Home Residents over Time

Science.gov (United States)

Cassie, Kimberly M.; Cassie, William E.

2012-01-01

Purpose: To examine the effect of organizational culture and climate on depressive symptoms among nursing home residents. Design and Methods: Using a pooled cross-sectional design, this study examines a sample of 23 nursing homes, 1,114 employees, and 5,497 residents. Depressive symptoms were measured using the Minimum Data Set, Depression Rating…

Use of tritium for estimation of groundwater mean residence time, a case study of the Ain Al-Samak Karst springs (Central Syria)

International Nuclear Information System (INIS)

Kattan, Z.

2003-01-01

This work is an attempt to estimate the mean residence time of groundwater in the Ain Al-Tanour and Ain-Samak, which are the major karst springs in the Upper Orontes Basin (Central Syria). This estimate, which consists on the application of a mathematical modeling approach, was based on the use of tritium, as a natural radioisotope tracer and a tool for ground water age dating. By adopting a completely mixed reservoir model, linked with exponential time distribution function, the mean residence time (turnover time) of these two springs was evaluated to be about 50 years. This result is in good agreement with previous estimation obtained for the Figeh main spring, which belongs to the same aquifer (Cenomanian-Turonian complex) in the Damascus Basin. On the basis of this evaluation, a value of about 800 million m 3 was obtained for the maximum groundwater reservoir size

Effects of Temperature and Residence Time on the Emissions of PIC and Fine Particles during Fixed Bed Combustion of Conifer Stemwood Pellets

Energy Technology Data Exchange (ETDEWEB)

Boman, Christoffer; Lindmark, Fredrik; Oehman, Marcus; Nordin, Anders [Umeaa Univ. (Sweden). Energy Technology and Thermal Process Chemistry; Pettersson, Esbjoern [Energy Technology Centre, Piteaa (Sweden); Westerholm, Roger [Stockholm Univ., Arrhenius Laboratory (Sweden). Dept. of Analytical Chemistry

2006-07-15

The use of wood fuel Pellets has proved to be well suited for the small-scale market enabling controlled and efficient combustion with low emission of products of incomplete combustion (PIC). Still a potential for further emission reduction exists and a thorough understanding of the influence of combustion conditions on the emission characteristics of air pollutants like PAH and particulate matter (PM) is important. The objective was to determine the effects of temperature and residence time on the emission performance and characteristics with focus on hydrocarbons and PM during combustion of conifer stemwood Pellets in a laboratory fixed bed reactor (<5 kW). Temperature and residence time after the bed section were varied according to statistical experimental designs (650-970 deg C and 0.5-3.5 s) with the emission responses; CO, organic gaseous carbon, NO, 20 VOC compounds, 43 PAH compounds, PM{sub tot}, fine particle mass/count median diameter (MMD and CMD) and number concentration. Temperature was negatively correlated with the emissions of all studied PIC with limited effects of residence time. The PM{sub tot} emissions of 15-20 mg/MJ was in all cases dominated by fine (<1 {mu}m) particles of K, Na, S, Cl, C, O and Zn. Increased residence time resulted in increased fine particle sizes (i.e. MMD and CMD) and decreased number concentrations. The importance of high temperature (>850 deg C) in the bed zone with intensive, air rich and well mixed isothermal conditions for 0.5-1.0 s in the post combustion zone was illustrated for wood Pellets combustion with almost a total depletion of all studied PIC. The results emphasize the need for further verification studies and technology development work.

An Analysis of Publication Productivity During Residency for 1506 Neurosurgical Residents and 117 Residency Departments in North America.

Science.gov (United States)

Khan, Nickalus R; Saad, Hassan; Oravec, Chesney S; Norrdahl, Sebastian P; Fraser, Brittany; Wallace, David; Lillard, Jock C; Motiwala, Mustafa; Nguyen, Vincent N; Lee, Siang Liao; Jones, Anna V; Ajmera, Sonia; Kalakoti, Piyush; Dave, Pooja; Moore, Kenneth A; Akinduro, Olutomi; Nyenwe, Emmanuel; Vaughn, Brandy; Michael, L Madison; Klimo, Paul

2018-05-30

Bibliometrics is defined as the study of statistical and mathematical methods used to quantitatively analyze scientific literature. The application of bibliometrics in neurosurgery continues to evolve. To calculate a number of publication productivity measures for almost all neurosurgical residents and departments within North America. These measures were correlated with survey results on the educational environment within residency programs. During May to June 2017, data were collected from departmental websites and Scopus to compose a bibliometric database of neurosurgical residents and residency programs. Data related to authorship value and study content were collected on all articles published by residents. A survey of residency program research and educational environment was administered to program directors and coordinators; results were compared with resident academic productivity. The median number of publications in residency was 3; median h-index and Resident index were 1 and 0.17 during residency, respectively. There was a statistically significant difference in academic productivity among male neurosurgical residents compared with females. The majority of articles published were tier 1 clinical articles. Residency program research support was significantly associated with increased resident productivity (P productivity. This study represents the most comprehensive bibliometric assessment of neurosurgical resident academic productivity during training to date. New benchmarks for individual and department academic productivity are provided. A supportive research environment for neurosurgical residents is associated with increased academic productivity, but a scholarly activity requirement was, surprisingly, not shown to have a positive effect.

Pregnancy and the Plastic Surgery Resident.

Science.gov (United States)

Garza, Rebecca M; Weston, Jane S; Furnas, Heather J

2017-01-01

Combining pregnancy with plastic surgery residency has historically been difficult. Two decades ago, 36 percent of plastic surgery program directors surveyed actively discouraged pregnancy among residents, and 33 percent of women plastic surgeons suffered from infertility. Most alarmingly, 26 percent of plastic surgery trainees had had an elective abortion during residency. With increasing numbers of women training in plastic surgery, this historical lack of support for pregnancy deserves further attention. To explore the current accommodations made for the pregnant plastic surgery resident, an electronic survey was sent to 88 plastic surgery program directors in the United States. Fifty-four responded, for a response rate of 61.36 percent. On average, a director trained a total of 7.91 women among 17.28 residents trained over 8.19 years. Of the women residents, 1.43 were pregnant during a director's tenure, with 1.35 of those residents taking maternity leave. An average 1.75 male residents took paternity leave. Approximately one-third of programs had a formal maternity/paternity leave policy (36.54 percent) which, in most cases, was limited to defining allowed weeks of leave, time required to fulfill program requirements, and remuneration during leave. This survey of plastic surgery directors is a first step in defining the challenges training programs face in supporting the pregnant resident. Directors provided comments describing their challenges accommodating an absent resident in a small program and complying with the American Board of Plastic Surgery's required weeks of training per year. A discussion of these challenges is followed by suggested solutions.

Fly Ash Formation during Suspension-Firing of Biomass. Effects of Residence Time and Fuel-Type

DEFF Research Database (Denmark)

Damø, Anne Juul; Jensen, Peter Arendt; Jappe Frandsen, Flemming

2017-01-01

particles were subjected to various analyses, including char burnout level, particle size distribution, elemental composition, and particle morphology and composition. Furthermore, the transient release, i.e. the vaporization of the flame-volatile inorganic elements K, Cl and S, from the burning fuel...... particles to the gas phase, has been quantified by using two different calculation methods. The ash formation mechanisms were found to be quite similar for straw and wood. The degree of conversion (char burn-out level) was generally good at residence times ≥ 1s. The size distribution of the residual fly ash...

Surgical Pathology Resident Rotation Restructuring at a Tertiary Care Academic Center.

Science.gov (United States)

Mehr, Chelsea R; Obstfeld, Amrom E; Barrett, Amanda C; Montone, Kathleen T; Schwartz, Lauren E

2017-01-01

Changes in the field of pathology and resident education necessitate ongoing evaluation of residency training. Evolutionary change is particularly important for surgical pathology rotations, which form the core of anatomic pathology training programs. In the past, we organized this rotation based on subjective insight. When faced with the recent need to restructure the rotation, we strove for a more evidence-based process. Our approach involved 2 primary sources of data. We quantified the number of cases and blocks submitted per case type to estimate workload and surveyed residents about the time required to gross specimens in all organ systems. A multidisciplinary committee including faculty, residents, and staff evaluated the results and used the data to model how various changes to the rotation would affect resident workload, turnaround time, and other variables. Finally, we identified rotation structures that equally distributed work and created a point-based system that capped grossing time for residents of different experience. Following implementation, we retrospectively compared turnaround time and duty hour violations before and after these changes and surveyed residents about their experiences with both systems. We evaluated the accuracy of the point-based system by examining grossing times and comparing them to the assigned point values. We found overall improvement in the rotation following the implementation. As there is essentially no literature on the subject of surgical pathology rotation organization, we hope that our experience will provide a road map to improve pathology resident education at other institutions.

Surgical Pathology Resident Rotation Restructuring at a Tertiary Care Academic Center

Directory of Open Access Journals (Sweden)

Chelsea R. Mehr MD

2017-11-01

Full Text Available Changes in the field of pathology and resident education necessitate ongoing evaluation of residency training. Evolutionary change is particularly important for surgical pathology rotations, which form the core of anatomic pathology training programs. In the past, we organized this rotation based on subjective insight. When faced with the recent need to restructure the rotation, we strove for a more evidence-based process. Our approach involved 2 primary sources of data. We quantified the number of cases and blocks submitted per case type to estimate workload and surveyed residents about the time required to gross specimens in all organ systems. A multidisciplinary committee including faculty, residents, and staff evaluated the results and used the data to model how various changes to the rotation would affect resident workload, turnaround time, and other variables. Finally, we identified rotation structures that equally distributed work and created a point-based system that capped grossing time for residents of different experience. Following implementation, we retrospectively compared turnaround time and duty hour violations before and after these changes and surveyed residents about their experiences with both systems. We evaluated the accuracy of the point-based system by examining grossing times and comparing them to the assigned point values. We found overall improvement in the rotation following the implementation. As there is essentially no literature on the subject of surgical pathology rotation organization, we hope that our experience will provide a road map to improve pathology resident education at other institutions.

Training on the clock: family medicine residency directors' responses to resident duty hours reform.

Science.gov (United States)

Peterson, Lars E; Johnson, Hillary; Pugno, Perry A; Bazemore, Andrew; Phillips, Robert L

2006-12-01

The Accreditation Council for Graduate Medical Education's 2003 restrictions on resident duty hours (RDH) raised concerns among educators about potential negative impacts on residents' training. In the early wake of these restrictions, little is known about how RDH reform impacts training in primary care. The authors surveyed family medicine (FM) residency program directors (PDs) for their perceptions of the impact of RDH regulations on training in primary care. All PDs of 472 FM residency programs were asked via list-serve to complete an anonymous Internet-based survey in the fall of 2004. The survey solicited PDs' opinions about changes in staff and in residents' training experiences with respect to implementation of RDH regulations. Descriptive and qualitative analyses were conducted. There were 369 partial and 328 complete responses, for a response rate of 69% (328/472). Effects of the RDH regulations are varied. Fifty percent of FMPDs report increased patient-care duties for attendings, whereas 42% report no increase. Nearly 80% of programs hired no additional staff. Sixty percent of programs eliminated postcall clinics, and nearly 40% implemented a night-float system. Administrative hassles and losses of professionalism, educational opportunity, and continuity of care were common concerns, but a sizeable minority feel that residents will be better off under the new regulations. Many FMPDs cited increased faculty burden and the risk of lower-quality educational experiences for their trainees. Innovations for increasing the effectiveness of teaching may ultimately compensate for lost educational time. If not, alternatives such as extending the length of residency must be considered.

Solid malignant neoplasms after childhood irradiation: decrease of the relative risk with time after irradiation

International Nuclear Information System (INIS)

Vathaire, F. de; Shamsaldin, A.; Grimaud, E.; Campbell, S.; Guerra, M.; Raquin, M.; Hardiman, C.; Jan, P.; Rumeau, N.; Diallo, I.; Nicolazic, G.; Lamon, A.; Oberlin, O.; Cervens, C. de; Suarez, A.; Meresse, V.; Eschwege, F.; Sancho-Garnier, H.; Chavaudra, J.; Lermerle, J.; Bessa, E.; Bell, J.; Hawkins, M.; Schlienger, J.Y.; Panis, X.; Lagrande, J.L.; Gaboriaud, G.; Zucker, J.M.; Daly-Schveitzer, N.

1995-01-01

The pattern of the temporal distribution of solid cancer incidence after irradiation in childhood is not well known, although, its importance in radioprotection is well known. We studied a cohort of 1 055 children from 8 European cancer centres, who received radiotherapy between 1942 and 1985 for a first cancer in childhood. After a mean follow-up of 19 years, 26 children developed a solid second malignant neoplasm (SMN), as compared to 5.6 expected from general population rates. Both the excess relative risk and the excess of absolute risk of solid SMN were higher among children who were younger at time of the irradiation. After reaching a maximum 15 to 20 years after irradiation, the excess relative risk of SMN decreased with time after irradiation, when controlling for age at irradiation and sex. The analysis of the risk of thyroid, brain and breast cancer together, as a function of the dose averaged on these 3 organs lead to similar results. (authors). 16 refs., 8 tabs., 2 figs

Comparison of Residence Time Distributions of Liquid for Different Types of Input Signal Using a Stimulus-Response Technique

Czech Academy of Sciences Publication Activity Database

Čermáková, Jiřina; Siyakatshana, N.; Šilar, F.; Kudrna, V.; Jahoda, M.; Machoň, V.

2003-01-01

Roč. 57, č. 6 (2003), s. 427-431 ISSN 0366-6352. [International Conference of Slovak Society of Chemical Engineering /30./. Tatranské Matliare, 26.05.2003-30.05.2003] Institutional research plan: CEZ:AV0Z4072921 Keywords : stirred tank * stimulus-response technique * residence time distribution Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.226, year: 2003

Variability in Benthic Exchange Rate, Depth, and Residence Time Beneath a Shallow Coastal Estuary

Science.gov (United States)

Russoniello, Christopher J.; Heiss, James W.; Michael, Holly A.

2018-03-01

Hydrodynamically driven benthic exchange of water between the water column and shallow seabed aquifer is a significant and dynamic component of coastal and estuarine fluid budgets. Associated exchange of solutes promotes ecologically important chemical reactions, so quantifying benthic exchange rates, depths, and residence times constrains coastal chemical cycling estimates. We present the first combined field, numerical, and analytical modeling investigation of wave-induced exchange. Temporal variability of exchange was calculated with data collected by instruments deployed in a shallow estuary for 11 days. Differential pressure sensors recorded pressure gradients across the seabed, and up- and down-looking ADCPs recorded currents and pressures to determine wave parameters, surface-water currents, and water depth. Wave-induced exchange was calculated (1) directly from differential pressure measurements, and indirectly with an analytical model based on wave parameters from (2) ADCP and (3) wind data. Wave-induced exchange from pressure measurements and ADCP-measured wave parameters matched well, but both exceeded wind-based values. Exchange induced by tidal pumping and current-bed form interaction—the other primary drivers in shallow coastal waters were calculated from tidal stage variation and ADCP-measured currents. Exchange from waves (mean = 20.0 cm/d; range = 1.75-92.3 cm/d) greatly exceeded exchange due to tides (mean = 3.7 cm/d) and current-bed form interaction (mean = 6.5 × 10-2 cm/d). Groundwater flow models showed aquifer properties affect wave-driven benthic exchange: residence time and depth increased and exchange rates decreased with increasing hydraulic diffusivity (ratio of aquifer permeability to compressibility). This new understanding of benthic exchange will help managers assess its control over chemical fluxes to marine systems.

Cooperative learning as applied to resident instruction in radiology reporting.

Science.gov (United States)

Mueller, Donald; Georges, Alexandra; Vaslow, Dale

2007-12-01

The study is designed to evaluate the effectiveness of an active form of resident instruction, cooperative learning, and the residents' response to that form of instruction. The residents dictated three sets of reports both before and after instruction in radiology reporting using the cooperative learning method. The reports were evaluated for word count, Flesch-Kincaid grade level, advancement on clinical spectrum, clarity, and comparison to prior reports. The reports were evaluated for changes in performance characteristics between the pre- and postinstruction dictations. The residents' response to this form of instruction was evaluated by means of a questionnaire. The instruction was effective in changing the resident dictations. The results became shorter (Pcooperative learning activities. The least positive responses related to the amount of time devoted to the project. Sixty-three percent of respondents stated that the time devoted to the project was appropriate. Cooperative learning can be an effective tool in the setting of the radiology residency. Instructional time requirements must be strongly considered in designing a cooperative learning program.

Perceptual Assessment of Velopharyngeal Dysfunction by Otolaryngology Residents.

Science.gov (United States)

Butts, Sydney C; Truong, Alan; Forde, Christina; Stefanov, Dimitre G; Marrinan, Eileen

2016-12-01

To assess the ability of otolaryngology residents to rate the hypernasal resonance of patients with velopharyngeal dysfunction. We hypothesize that experience (postgraduate year [PGY] level) and training will result in improved ratings of speech samples. Prospective cohort study. Otolaryngology training programs at 2 academic medical centers. Thirty otolaryngology residents (PGY 1-5) were enrolled in the study. All residents rated 30 speech samples at 2 separate times. Half the residents completed a training module between the rating exercises, with the other half serving as a control group. Percentage agreement with the expert rating of each speech sample and intrarater reliability were calculated for each resident. Analysis of covariance was used to model accuracy at session 2. The median percentage agreement at session 1 was 53.3% for all residents. At the second session, the median scores were 53.3% for the control group and 60% for the training group, but this difference was not statistically significant. Intrarater reliability was moderate for both groups. Residents were more accurate in their ratings of normal and severely hypernasal speech. There was no correlation between rating accuracy and PGY level. Score at session 1 positively correlated with score at session 2. Perceptual training of otolaryngology residents has the potential to improve their ratings of hypernasal speech. Length of time in residency may not be best predictor of perceptual skill. Training modalities incorporating practice with hypernasal speech samples could improve rater skills and should be studied more extensively. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

Solid waste bin detection and classification using Dynamic Time Warping and MLP classifier

Energy Technology Data Exchange (ETDEWEB)

Islam, Md. Shafiqul, E-mail: shafique@eng.ukm.my [Dept. of Electrical, Electronic and Systems Engineering, Universiti Kebangsaan Malaysia, Bangi 43600, Selangore (Malaysia); Hannan, M.A., E-mail: hannan@eng.ukm.my [Dept. of Electrical, Electronic and Systems Engineering, Universiti Kebangsaan Malaysia, Bangi 43600, Selangore (Malaysia); Basri, Hassan [Dept. of Civil and Structural Engineering, Universiti Kebangsaan Malaysia, Bangi 43600, Selangore (Malaysia); Hussain, Aini; Arebey, Maher [Dept. of Electrical, Electronic and Systems Engineering, Universiti Kebangsaan Malaysia, Bangi 43600, Selangore (Malaysia)

2014-02-15

Highlights: • Solid waste bin level detection using Dynamic Time Warping (DTW). • Gabor wavelet filter is used to extract the solid waste image features. • Multi-Layer Perceptron classifier network is used for bin image classification. • The classification performance evaluated by ROC curve analysis. - Abstract: The increasing requirement for Solid Waste Management (SWM) has become a significant challenge for municipal authorities. A number of integrated systems and methods have introduced to overcome this challenge. Many researchers have aimed to develop an ideal SWM system, including approaches involving software-based routing, Geographic Information Systems (GIS), Radio-frequency Identification (RFID), or sensor intelligent bins. Image processing solutions for the Solid Waste (SW) collection have also been developed; however, during capturing the bin image, it is challenging to position the camera for getting a bin area centralized image. As yet, there is no ideal system which can correctly estimate the amount of SW. This paper briefly discusses an efficient image processing solution to overcome these problems. Dynamic Time Warping (DTW) was used for detecting and cropping the bin area and Gabor wavelet (GW) was introduced for feature extraction of the waste bin image. Image features were used to train the classifier. A Multi-Layer Perceptron (MLP) classifier was used to classify the waste bin level and estimate the amount of waste inside the bin. The area under the Receiver Operating Characteristic (ROC) curves was used to statistically evaluate classifier performance. The results of this developed system are comparable to previous image processing based system. The system demonstration using DTW with GW for feature extraction and an MLP classifier led to promising results with respect to the accuracy of waste level estimation (98.50%). The application can be used to optimize the routing of waste collection based on the estimated bin level.

Automated medical resident rotation and shift scheduling to ensure quality resident education and patient care.

Science.gov (United States)

Smalley, Hannah K; Keskinocak, Pinar

2016-03-01

At academic teaching hospitals around the country, the majority of clinical care is provided by resident physicians. During their training, medical residents often rotate through various hospitals and/or medical services to maximize their education. Depending on the size of the training program, manually constructing such a rotation schedule can be cumbersome and time consuming. Further, rules governing allowable duty hours for residents have grown more restrictive in recent years (ACGME 2011), making day-to-day shift scheduling of residents more difficult (Connors et al., J Thorac Cardiovasc Surg 137:710-713, 2009; McCoy et al., May Clin Proc 86(3):192, 2011; Willis et al., J Surg Edu 66(4):216-221, 2009). These rules limit lengths of duty periods, allowable duty hours in a week, and rest periods, to name a few. In this paper, we present two integer programming models (IPs) with the goals of (1) creating feasible assignments of residents to rotations over a one-year period, and (2) constructing night and weekend call-shift schedules for the individual rotations. These models capture various duty-hour rules and constraints, provide the ability to test multiple what-if scenarios, and largely automate the process of schedule generation, solving these scheduling problems more effectively and efficiently compared to manual methods. Applying our models on data from a surgical residency program, we highlight the infeasibilities created by increased duty-hour restrictions placed on residents in conjunction with current scheduling paradigms.

Applying Expectancy Theory to residency training: proposing opportunities to understand resident motivation and enhance residency training.

Science.gov (United States)

Shweiki, Ehyal; Martin, Niels D; Beekley, Alec C; Jenoff, Jay S; Koenig, George J; Kaulback, Kris R; Lindenbaum, Gary A; Patel, Pankaj H; Rosen, Matthew M; Weinstein, Michael S; Zubair, Muhammad H; Cohen, Murray J

2015-01-01

Medical resident education in the United States has been a matter of national priority for decades, exemplified initially through the Liaison Committee for Graduate Medical Education and then superseded by the Accreditation Council for Graduate Medical Education. A recent Special Report in the New England Journal of Medicine, however, has described resident educational programs to date as prescriptive, noting an absence of innovation in education. Current aims of contemporary medical resident education are thus being directed at ensuring quality in learning as well as in patient care. Achievement and work-motivation theories attempt to explain people's choice, performance, and persistence in tasks. Expectancy Theory as one such theory was reviewed in detail, appearing particularly applicable to surgical residency training. Correlations between Expectancy Theory as a work-motivation theory and residency education were explored. Understanding achievement and work-motivation theories affords an opportunity to gain insight into resident motivation in training. The application of Expectancy Theory in particular provides an innovative perspective into residency education. Afforded are opportunities to promote the development of programmatic methods facilitating surgical resident motivation in education.

Real-Time Inhibitor Recession Measurements in Two Space Shuttle Reusable Solid Rocket Motors

Science.gov (United States)

McWhorter, B. B.; Ewing, M. E.; Bolton, D. E.; Albrechtsen, K. U.; Earnest, T. E.; Noble, T. C.; Longaker, M.

2003-01-01

Real-time internal motor insulation char line recession measurements have been evaluated for two full-scale static tests of the Space Shuttle Reusable Solid Rocket Motor (RSRM). These char line recession measurements were recorded on the forward facing propellant grain inhibitors to better understand the thermal performance of these inhibitors. The RSRM propellant grain inhibitors are designed to erode away during motor operation, thus making it difficult to use post-fire observations to determine inhibitor thermal performance. Therefore, this new internal motor instrumentation is invaluable in establishing an accurate understanding of inhibitor recession versus motor operation time. The data for the first test was presented at the 37th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (AIAA 2001-3280) in July 2001. Since that time, a second full scale static test has delivered additional real-time data on inhibitor thermal performance. The evaluation of this data is presented in this paper. The second static test, in contrast to the first test, used a slightly different arrangement of instrumentation in the inhibitors. This instrumentation has yielded a better understanding of the inhibitor time dependent inboard tip recession. Graphs of inhibitor recession profiles with time are presented. Inhibitor thermal ablation models have been created from theoretical principals. The model predictions compare favorably with data from both tests. This verified modeling effort is important to support new inhibitor designs for a five segment Space Shuttle solid rocket motor. The internal instrumentation project on RSRM static tests is providing unique opportunities for other real-time internal motor measurements that could not otherwise be directly quantified.

Trait differences between naturalized and invasive plant species independent of residence time and phylogeny.

Science.gov (United States)

Gallagher, R V; Randall, R P; Leishman, M R

2015-04-01

The ability to predict which alien plants will transition from naturalized to invasive prior to their introduction to novel regions is a key goal for conservation and has the potential to increase the efficacy of weed risk assessment (WRA). However, multiple factors contribute to plant invasion success (e.g., functional traits, range characteristics, residence time, phylogeny), and they all must be taken into account simultaneously in order to identify meaningful correlates of invasion success. We compiled 146 pairs of phylogenetically paired (congeneric) naturalized and invasive plant species in Australia with similar minimum residence times (i.e., time since introduction in years). These pairs were used to test for differences in 5 functional traits (flowering duration, leaf size, maximum height, specific leaf area [SLA], seed mass) and 3 characteristics of species' native ranges (biome occupancy, mean annual temperature, and rainfall breadth) between naturalized and invasive species. Invasive species, on average, had larger SLA, longer flowering periods, and were taller than their congeneric naturalized relatives. Invaders also exhibited greater tolerance for different environmental conditions in the native range, where they occupied more biomes and a wider breadth of rainfall and temperature conditions than naturalized congeners. However, neither seed mass nor leaf size differed between pairs of naturalized and invasive species. A key finding was the role of SLA in distinguishing between naturalized and invasive pairs. Species with high SLA values were typically associated with faster growth rates, more rapid turnover of leaf material, and shorter lifespans than those species with low SLA. This suite of characteristics may contribute to the ability of a species to transition from naturalized to invasive across a wide range of environmental contexts and disturbance regimes. Our findings will help in the refinement of WRA protocols, and we advocate the inclusion

Trends in violence education in family medicine residency curricula.

Science.gov (United States)

Cronholm, Peter F; Singh, Vijay; Fogarty, Colleen T; Ambuel, Bruce

2014-09-01

Violence is a significant public health issue with far-reaching implications for the health of individuals and their communities. Our objective was to describe trends in violence-related training in family medicine residency programs since the last national survey was conducted in 1997. Surveys were sent to 337 US family medicine residency programs with the program director having active Society of Teachers of Family Medicine (STFM) membership. Measures included residency setting and characteristics, violence-related curricular content, teaching techniques and personnel, timing of content, and impact of changes in Residency Review Committee (RRC) and Accreditation Council for Graduate Medical Education (ACGME) requirements. Descriptive statistics and bivariate analyses comparing measures across time were used. A total of 201 (60%) surveys were completed. The most common violence curricula was child (83%) and elder abuse (76%), and the most common teachers of violence-related content were family physicians, psychologists, and social workers. The most common teaching methods were clinical precepting (94%), lectures (90%), case vignettes (71%), and intimate partner violence (IPV) shelter experiences (67%). ACGME and RRC changes were not reflected in self-reported measures of curricular emphasis or time. Violence curricular content and number of hours has been constant in family medicine residencies over time. An increase in the reported use of active learning strategies was identified as a trend across surveys. Next steps for violence curricula involve assessment of residents' competency to identify and intervene in violence.

Psychiatric Emergency Services - Can Duty-Hour Changes Help Residents and Patients?

Science.gov (United States)

Brainch, Navjot; Schule, Patrick; Laurel, Faith; Bodic, Maria; Jacob, Theresa

2018-04-14

Limitations on resident duty hours have been widely introduced with the intention of decreasing resident fatigue and improving patient outcomes. While there is evidence of improvement in resident well-being and education following such initiatives, they have inadvertently resulted in increased number of hand-offs between clinicians leading to potential errors in patient care. Current literature emphasizes need for more specialty/setting-specific scheduling, while considering residents' opinions when implementing duty-hour reforms. There are no reports examining the impact of duty-hour changes on residents or patients in psychiatric emergency service (PES) settings. Our purpose was to assess the impact of a recent scheduling change and decrease in overall duty hours, on resident well-being and sense of burnout, while also evaluating changes to patient wait-time and length of stay (LOS) in PES. Residents completed Maslach Burnout Inventory and anonymous surveys focusing on: fatigue, sleep, life outside work for shifts - regular (8 am-8 pm) and swing shifts (12 pm-10 pm). Data from the electronic medical records were collected for 6 months pre- and post-schedule change (January 2016-February 2017), for LOS and patient wait-time. Residents' preference for shifts was split. However, 86% reported getting enough sleep during swing shifts, while 83% reported lack of sleep during regular shifts. The average patient wait-time and LOS significantly decreased from 169 to 147 and 690 to 515 min, respectively. The change to swing shifts significantly impacts LOS and patient wait-time. The short shifts demonstrated an improvement in well-being for residents, but were not the singular factor for overall resident satisfaction.

Teaching leadership in trauma resuscitation: Immediate feedback from a real-time, competency-based evaluation tool shows long-term improvement in resident performance.

Science.gov (United States)

Gregg, Shea C; Heffernan, Daithi S; Connolly, Michael D; Stephen, Andrew H; Leuckel, Stephanie N; Harrington, David T; Machan, Jason T; Adams, Charles A; Cioffi, William G

2016-10-01

Limited data exist on how to develop resident leadership and communication skills during actual trauma resuscitations. An evaluation tool was developed to grade senior resident performance as the team leader during full-trauma-team activations. Thirty actions that demonstrated the Accreditation Council for Graduate Medical Education core competencies were graded on a Likert scale of 1 (poor) to 5 (exceptional). These actions were grouped by their respective core competencies on 5 × 7-inch index cards. In Phase 1, baseline performance scores were obtained. In Phase 2, trauma-focused communication in-services were conducted early in the academic year, and immediate, personalized feedback sessions were performed after resuscitations based on the evaluation tool. In Phase 3, residents received only evaluation-based feedback following resuscitations. In Phase 1 (October 2009 to April 2010), 27 evaluations were performed on 10 residents. In Phase 2 (April 2010 to October 2010), 28 evaluations were performed on nine residents. In Phase 3 (October 2010 to January 2012), 44 evaluations were performed on 13 residents. Total scores improved significantly between Phases 1 and 2 (p = 0.003) and remained elevated throughout Phase 3. When analyzing performance by competency, significant improvement between Phases 1 and 2 (p competencies (patient care, knowledge, system-based practice, practice-based learning) with the exception of "communication and professionalism" (p = 0.56). Statistically similar scores were observed between Phases 2 and 3 in all competencies with the exception of "medical knowledge," which showed ongoing significant improvement (p = 0.003). Directed resident feedback sessions utilizing data from a real-time, competency-based evaluation tool have allowed us to improve our residents' abilities to lead trauma resuscitations over a 30-month period. Given pressures to maximize clinical educational opportunities among work-hour constraints, such a model may help

Creating a Residency Application Personal Statement Writers Workshop: Fostering Narrative, Teamwork, and Insight at a Time of Stress.

Science.gov (United States)

Campbell, Bruce H; Havas, Nancy; Derse, Arthur R; Holloway, Richard L

2016-03-01

Every graduating medical student must write a personal statement for the Electronic Residency Application Service (ERAS), yet there are no widely available resources designed to aid the writing process, causing stress among applicants. The authors offered every Medical College of Wisconsin senior student in the Classes of 2014 and 2015 a voluntary self-contained two-hour Residency Application Personal Statement Writers Workshop. The session included the selection of writing prompts, speedwriting, and a peer-edit critique. Data were gathered before and after each workshop and at the time of ERAS submission. One hundred nine students elected to participate. Of the 96 participants completing a preworkshop questionnaire, only 28 (29%) were comfortable with creative and reflective writing. Fifty-four students completed a follow-up survey after submitting their ERAS application. Fifty-one (94%) found the session effective in getting their personal statement started, and 65 (70%) were surprised by the quality of their writing. Almost all could trace some of their final statement to the workshop. Forty-six (85%) found working with other students helpful, and 49 (91%) would recommend the session to future students; 47 (87%) agreed that the workshop was "fun." The full workshop will be repeated yearly. Workshops will also be offered to residents preparing fellowship applications. A shorter version (without the peer-edit critique) was used successfully with the entire Class of 2016 to help them reflect on their initial clinical encounters. The authors will seek further opportunities to enhance reflection for students, residents, and faculty with these techniques.

Multiple time scale analysis of pressure oscillations in solid rocket motors

Science.gov (United States)

Ahmed, Waqas; Maqsood, Adnan; Riaz, Rizwan

2018-03-01

In this study, acoustic pressure oscillations for single and coupled longitudinal acoustic modes in Solid Rocket Motor (SRM) are investigated using Multiple Time Scales (MTS) method. Two independent time scales are introduced. The oscillations occur on fast time scale whereas the amplitude and phase changes on slow time scale. Hopf bifurcation is employed to investigate the properties of the solution. The supercritical bifurcation phenomenon is observed for linearly unstable system. The amplitude of the oscillations result from equal energy gain and loss rates of longitudinal acoustic modes. The effect of linear instability and frequency of longitudinal modes on amplitude and phase of oscillations are determined for both single and coupled modes. For both cases, the maximum amplitude of oscillations decreases with the frequency of acoustic mode and linear instability of SRM. The comparison of analytical MTS results and numerical simulations demonstrate an excellent agreement.

Association of the 2011 ACGME resident duty hour reform with general surgery patient outcomes and with resident examination performance.

Science.gov (United States)

Rajaram, Ravi; Chung, Jeanette W; Jones, Andrew T; Cohen, Mark E; Dahlke, Allison R; Ko, Clifford Y; Tarpley, John L; Lewis, Frank R; Hoyt, David B; Bilimoria, Karl Y

2014-12-10

In 2011, the Accreditation Council for Graduate Medical Education (ACGME) restricted resident duty hour requirements beyond those established in 2003, leading to concerns about the effects on patient care and resident training. To determine if the 2011 ACGME duty hour reform was associated with a change in general surgery patient outcomes or in resident examination performance. Quasi-experimental study of general surgery patient outcomes 2 years before (academic years 2009-2010) and after (academic years 2012-2013) the 2011 duty hour reform. Teaching and nonteaching hospitals were compared using a difference-in-differences approach adjusted for procedural mix, patient comorbidities, and time trends. Teaching hospitals were defined based on the proportion of cases at which residents were present intraoperatively. Patients were those undergoing surgery at hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP). General surgery resident performance on the annual in-training, written board, and oral board examinations was assessed for this same period. National implementation of revised resident duty hour requirements on July 1, 2011, in all ACGME accredited residency programs. Primary outcome was a composite of death or serious morbidity; secondary outcomes were other postoperative complications and resident examination performance. In the main analysis, 204,641 patients were identified from 23 teaching (n = 102,525) and 31 nonteaching (n = 102,116) hospitals. The unadjusted rate of death or serious morbidity improved during the study period in both teaching (11.6% [95% CI, 11.3%-12.0%] to 9.4% [95% CI, 9.1%-9.8%], P adverse outcome. Mean (SD) in-training examination scores did not significantly change from 2010 to 2013 for first-year residents (499.7 [ 85.2] to 500.5 [84.2], P = .99), for residents from other postgraduate years, or for first-time examinees taking the written or oral board

Practice gaps in patient safety among dermatology residents and their teachers: a survey study of dermatology residents.

Science.gov (United States)

Swary, Jillian Havey; Stratman, Erik J

2014-07-01

Curriculum and role modeling adjustments are necessary to address patient safety gaps occurring during dermatology residency. To identify the source of clinical practices among dermatology residents that affect patient safety and determine the best approach for overcoming gaps in knowledge and practice patterns that contribute to these practices. A survey-based study, performed at a national medical dermatology meeting in Itasca, Illinois, in 2012, included 142 dermatology residents from 44 residency programs in the United States and Canada. Self-reported rates of dermatology residents committing errors, identifying local systems errors, and identifying poor patient safety role modeling. Of surveyed dermatology residents, 45.2% have failed to report needle-stick injuries incurred during procedures, 82.8% reported cutting and pasting a previous author's patient history information into a medical record without confirming its validity, 96.7% reported right-left body part mislabeling during examination or biopsy, and 29.4% reported not incorporating clinical photographs of lesions sampled for biopsy in the medical record at their institution. Residents variably perform a purposeful pause ("time-out") when indicated to confirm patient, procedure, and site before biopsy, with 20.0% always doing so. In addition, 59.7% of residents work with at least 1 attending physician who intimidates the residents, reducing the likelihood of reporting safety issues they witness. Finally, 78.3% have witnessed attending physicians purposefully disregarding required safety steps. Our data reinforce the need for modified curricula, systems, and teacher development to reduce injuries, improve communication with patients and between physicians, residents, and other members of the health care team, and create an environment free of intimidation.

Career goals and expectations of men and women pharmacy residents.

Science.gov (United States)

King, C M; Oliver, E J; Jeffrey, L P

1982-11-01

Personal and professional characteristics of men and women hospital pharmacy residents were studied to identify differences that could affect future hospital pharmacy practice. Residents in 111 ASHP-accredited pharmacy residency programs received a survey containing questions on demographic information, reasons for selecting a residency, areas of professional interest, postresidency career goals, responsibilities to home and family, and advantages and disadvantages associated with gender. Of 286 residents receiving questionnaires, 226 responded; the percentages of men and women responding corresponded to the ratio of men and women in hospital pharmacy residencies. While men and women expressed educational goals that were not significantly different, more men than women had earned or were in the process of earning advanced degrees. No significant differences were evident between men's and women's plans for marriage and children, but 73% of the women indicated that they would take time out from their practice to raise children, compared with only 9% of the men. The majority of residents did not think their gender affected them in their residency programs, but in professional interactions more men saw gender as an advantage and more women as a disadvantage. Significantly more than women aspired to be hospital pharmacy directors. The results suggest that men are obtaining advanced training closer to the time they graduate from pharmacy school and that in the future women competing for promotions may be older than men competing for comparable positions. Those planning pharmacy staffing should consider the needs of women, and men, who expect to take time out from their careers for family responsibilities and possibly seek part-time positions when they return to the work force.

Increasing faculty participation in resident education and providing cost-effective self-assessment module credit to faculty through resident-generated didactics.

Science.gov (United States)

Kim, Hyun; Malatesta, Theresa M; Anné, Pramila R; McAna, John; Bar-Ad, Voichita; Dicker, Adam P; Den, Robert B

Board certified radiation oncologists and medical physicists are required to earn self-assessment module (SAM) continuing medical education (CME) credit, which may require travel costs or usage fees. Data indicate that faculty participation in resident teaching activities is beneficial to resident education. Our hypothesis was that providing the opportunity to earn SAM credit in resident didactics would increase faculty participation in and improve resident education. SAM applications, comprising CME certified category 1 resident didactic lectures and faculty-generated questions with respective answers, rationales, and references, were submitted to the American Board of Radiology for formal review. Surveys were distributed to assess main academic campus physician, affiliate campus physician, physicist, and radiation oncology resident impressions regarding the quality of the lectures. Survey responses were designed in Likert-scale format. Sign-test was performed with P motivation to attend resident didactics (P = .004). Residents reported an increased amount of time required to prepare lectures (P = .008). We are the first department, to our knowledge, to offer SAM credit to clinical faculty for participation in resident-generated didactics. Offering SAM credit at resident lectures is a cost-effective alternative to purchasing SAM resources, increases faculty attendance, and may improve the quality of radiation oncology resident education. Copyright © 2016 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Burnout, Perceived Stress, and Depression among Cardiology Residents in Argentina

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Waldman, Silvina V.; Diez, Juan Cruz Lopez; Arazi, Hernan Cohen; Linetzky, Bruno; Guinjoan, Salvador; Grancelli, Hugo

2009-01-01

Objective: Because medical residency is a stressful time for training physicians, placing residents at increased risk for psychological distress, the authors studied the prevalence of burnout, perceived stress, and depression in cardiology residents in Argentina and examined the association between sociodemographic characteristics and these…

Watershed Influences on Residence Time and Oxygen Reduction Rates in an Agricultural Landscape

Science.gov (United States)

Shope, C. L.; Tesoriero, A. J.

2015-12-01

Agricultural use of synthetic fertilizers and animal manure has led to increased crop production, but also elevated nitrogen concentrations in groundwater, resulting in impaired water quality. Groundwater oxygen concentrations are a key indicator of potential biogeochemical processes, which control water/aquifer interactions and contaminant transport. The U.S. Geological Survey's National Water-Quality Assessment Program has a long-history of studying nutrient transport and processing across the United States and the Glacial Aquifer system in particular. A series of groundwater well networks in Eastern Wisconsin is being used to evaluate the distribution of redox reaction rates over a range of scales with a focus on dissolved O2 reduction rates. An analysis of these multi-scale networks elucidates the influence of explanatory variables (i.e.: soil type, land use classification) on reduction rates and redox reactions throughout the Fox-Wolf-Peshtigo watersheds. Multiple tracers including dissolved gasses, tritium, helium, chlorofluorocarbons, sulfur hexafluoride, and carbon-14 were used to estimate groundwater ages (0.8 to 61.2 yr) at over 300 locations. Our results indicate O2 reduction rates along a flowpath study area (1.2 km2) of 0.15 mg O2 L-1 yr-1 (0.12 to 0.18 mg O2 L-1 yr-1) up to 0.41 mg O2 L-1 yr-1 (0.23 to 0.89 mg O2 L-1 yr-1) for a larger scale land use study area (3,300 km2). Preliminary explanatory variables that can be used to describe the variability in reduction rates include soil type (hydrologic group, bulk density) and chemical concentrations (nitrite plus nitrate, silica). The median residence time expected to reach suboxic conditions (≤ 0.4 mg O2 L-1) for the flowpath and the land use study areas was 66 and 25 yr, respectively. These results can be used to elucidate and differentiate the impact of residence time on groundwater quality vulnerability and sustainability in agricultural regions without complex flow models.

Development of Solid Ceramic Dosimeters for the Time-Integrative Passive Sampling of Volatile Organic Compounds in Waters.

Science.gov (United States)

Bonifacio, Riza Gabriela; Nam, Go-Un; Eom, In-Yong; Hong, Yong-Seok

2017-11-07

Time-integrative passive sampling of volatile organic compounds (VOCs) in water can now be accomplished using a solid ceramic dosimeter. A nonporous ceramic, which excludes the permeation of water, allowing only gas-phase diffusion of VOCs into the resin inside the dosimeter, effectively captured the VOCs. The mass accumulation of 11 VOCs linearly increased with time over a wide range of aqueous-phase concentrations (16.9 to 1100 μg L -1 ), and the linearity was dependent upon the Henry's constant (H). The average diffusivity of the VOCs in the solid ceramic was 1.46 × 10 -10 m 2 s -1 at 25 °C, which was 4 orders of magnitude lower than that in air (8.09 × 10 -6 m 2 s -1 ). This value was 60% greater than that in the water-permeable porous ceramic (0.92 × 10 -10 m 2 s -1 ), suggesting that its mass accumulation could be more effective than that of porous ceramic dosimeters. The mass accumulation of the VOCs in the solid ceramic dosimeter increased in the presence of salt (≥0.1 M) and with increasing temperature (4 to 40 °C) but varied only slightly with dissolved organic matter concentration. The solid ceramic dosimeter was suitable for the field testing and measurement of time-weighted average concentrations of VOC-contaminated waters.

Associations of psychosocial working conditions and working time characteristics with somatic complaints in German resident physicians.

Science.gov (United States)

Fischer, Nina; Degen, Christiane; Li, Jian; Loerbroks, Adrian; Müller, Andreas; Angerer, Peter

2016-05-01

Somatic complaints (SC) are highly prevalent in working populations and cause suffering and extensive health-care utilization. Adverse psychosocial working conditions as conceptualized in the Job Demand-Control-Support Model (JDC-S) and adverse working time characteristics (WTC) are potential risk factors. This combination is particularly common in hospital physicians. This study examines associations of JDC-S and WTC with SC in resident physicians from Germany. A cross-sectional study was conducted among 405 physicians at the end of residency training. SC were measured using the Giessen Subjective Complaints List (GBB-24) containing the sub-categories exhaustion, gastrointestinal, musculoskeletal, and cardiovascular complaints. Data on working conditions were collected by a self-report method for work analysis in hospitals (TAA-KH-S) and by questions on WTC (i.e., working hours). Multivariable stepwise regression analyses were applied. Workload showed the most pronounced relationship with all sub-categories of SC except gastrointestinal complaints. Job autonomy was not significantly related to any SC sub-category. Social support at work was inversely associated with all SC sub-categories except for cardiovascular complaints. Free weekends were associated with reduced SC except for exhaustion. Shift work was related to an increased SC total score and musculoskeletal complaints. Working hours showed no association with SC. In resident physicians, high workload and shift work are associated with increased SC, while social support at work and free weekends are associated with decreased SC. These insights may inform the development of preventive measures to improve the health of this professional group. Prospective studies are needed though to corroborate our findings.

Hydraulic paths and estimation of the real residence time of the water in Lago Maggiore (N. Italy: application of massless markers transported in 3D motion fields

Directory of Open Access Journals (Sweden)

Nicoletta Sala

2012-01-01

Full Text Available This study, conducted using the TRIM_LM model, is a continuation of work on the movement of the water mass at different depths in Lago Maggiore, and thus on the estimation of the real residence time of the water in the lake. Three-dimensional CFD numerical simulations were extended to a 4-year period, focusing on the movements of 202 (two hundred and two massless markers inserted at different points in Lago Maggiore and at the mouths of 11 of its tributaries, enabling us to establish more realistic water renewal times for Lago Maggiore. By crossing the data of the horizontal trajectories of the environmental markers with those of their vertical variations, we reconstructed their movements over the four years of the simulation programme. An analysis of the results shows that the water mass in the layers of the upper 100 m has residence times between a minimum of 1 y and a maximum of 4-5 y. The water from the tributaries has residence times between 250 and 1000 days, depending on the distance of the tributaries from the closing section of the lake. The water in the layers below 100 m has residence times that still cannot be quantified with precision, but that can certainly be estimated at a number of years in two figures. These times are strongly conditioned by the depth of the late winter mixing, which in the last 40 y has not exceeded 200 m.

Early resident-to-resident physics education in diagnostic radiology.

Science.gov (United States)

Kansagra, Akash P

2014-01-01

The revised ABR board certification process has updated the method by which diagnostic radiology residents are evaluated for competency in clinical radiologic physics. In this work, the author reports the successful design and implementation of a resident-taught physics course consisting of 5 weekly, hour-long lectures intended for incoming first-year radiology residents in their first month of training. To the author's knowledge, this is the first description of a course designed to provide a very early framework for ongoing physics education throughout residency without increasing the didactic burden on faculty members. Twenty-six first-year residents spanning 2 academic years took the course and reported subjective improvement in their knowledge (90%) and interest (75%) in imaging physics and a high level of satisfaction with the use of senior residents as physics educators. Based on the success of this course and the minimal resources required for implementation, this work may serve as a blueprint for other radiology residency programs seeking to develop revised physics curricula. Copyright © 2014 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Combustion of metal agglomerates in a solid rocket core flow

Science.gov (United States)

Maggi, Filippo; Dossi, Stefano; DeLuca, Luigi T.

2013-12-01

The need for access to space may require the use of solid propellants. High thrust and density are appealing features for different applications, spanning from boosting phase to other service applications (separation, de-orbiting, orbit insertion). Aluminum is widely used as a fuel in composite solid rocket motors because metal oxidation increases enthalpy release in combustion chamber and grants higher specific impulse. Combustion process of metal particles is complex and involves aggregation, agglomeration and evolution of reacting particulate inside the core flow of the rocket. It is always stated that residence time should be enough in order to grant complete metal oxidation but agglomerate initial size, rocket grain geometry, burning rate, and other factors have to be reconsidered. New space missions may not require large rocket systems and metal combustion efficiency becomes potentially a key issue to understand whether solid propulsion embodies a viable solution or liquid/hybrid systems are better. A simple model for metal combustion is set up in this paper. Metal particles are represented as single drops trailed by the core flow and reacted according to Beckstead's model. The fluid dynamics is inviscid, incompressible, 1D. The paper presents parametric computations on ideal single-size particles as well as on experimental agglomerate populations as a function of operating rocket conditions and geometries.

Estimation of Transport Trajectory and Residence Time in Large River–Lake Systems: Application to Poyang Lake (China Using a Combined Model Approach

Directory of Open Access Journals (Sweden)

Yunliang Li

2015-09-01

Full Text Available The biochemical processes and associated water quality in many lakes mainly depend on their transport behaviors. Most existing methodologies for investigating transport behaviors are based on physically based numerical models. The pollutant transport trajectory and residence time of Poyang Lake are thought to have important implications for the steadily deteriorating water quality and the associated rapid environmental changes during the flood period. This study used a hydrodynamic model (MIKE 21 in conjunction with transport and particle-tracking sub-models to provide comprehensive investigation of transport behaviors in Poyang Lake. Model simulations reveal that the lake’s prevailing water flow patterns cause a unique transport trajectory that primarily develops from the catchment river mouths to the downstream area along the lake’s main flow channels, similar to a river-transport behavior. Particle tracking results show that the mean residence time of the lake is 89 days during July–September. The effect of the Yangtze River (the effluent of the lake on the residence time is stronger than that of the catchment river inflows. The current study represents a first attempt to use a combined model approach to provide insights into the transport behaviors for a large river–lake system, given proposals to manage the pollutant inputs both directly to the lake and catchment rivers.

Severity of Neuropsychiatric Symptoms in Nursing Home Residents

Directory of Open Access Journals (Sweden)

Anne-Sofie Helvik

2016-01-01

Full Text Available We aimed at assessing time shift in the severity of neuropsychiatric symptoms (NPS in nursing home residents between 2004/2005 and 2010/2011 and associations between NPS and socio-demographic variables, physical health status, dementia severity, and the use of psychotropic drugs. The Neuropsychiatric Inventory Nursing Home Version was used in 2004/2005 (n = 1,163 and 2010/2011 (n = 1,858. Linear mixed model analysis was applied. There was no time shift in the severity of apathy, psychosis, and affective symptoms, but agitation did exhibit a time shift. Agitation was less severe in 2010/2011 than in 2004/2005 in residents with a Clinical Dementia Rating (CDR sum of boxes score ≤4, and more severe in residents with a CDR sum of boxes score >16. Higher CDR sum of boxes scores and use of psychotropic medication were associated with more severe apathy, agitation, psychosis, and affective symptoms. Poor physical health was associated with more severe apathy, psychosis, and affective symptoms. Women had more severe agitation and less severe affective symptoms than men. A longer stay in a nursing home was associated with more severe agitation and less severe affective symptoms. In conclusion, agitation was less severe in 2010/2011 than in 2004/2005 among nursing home residents with a milder degree of dementia, and more severe in residents with severe dementia.

More Learning in Less Time: Optimizing the Resident Educational Experience with Limited Clinical and Educational Work Hours.

Science.gov (United States)

Sedney, Cara L; Spirou, Eleni; Voelker, Joseph L; Rosen, Charles L

2017-11-01

Resident education in the United States and elsewhere has undergone significant changes in recent years owing to work hour restrictions, requiring didactics to fit within a limited schedule, while being increasingly effective at accomplishing educational goals. A single small program experience in improving the didactic experience of residents is described. Focused mentorship, curricula for intangibles, asynchronous education, and independent curricula all are useful tools in resident education. Residents can be exposed to both clinical material and specialty-specific mores using focused and intentional educational techniques. Copyright © 2017 Elsevier Inc. All rights reserved.

Use of social media by residency program directors for resident selection.

Science.gov (United States)

Cain, Jeff; Scott, Doneka R; Smith, Kelly

2010-10-01

Pharmacy residency program directors' attitudes and opinions regarding the use of social media in residency recruitment and selection were studied. A 24-item questionnaire was developed, pilot tested, revised, and sent to 996 residency program directors via SurveyMonkey.com. Demographic, social media usage, and opinions on social media data were collected and analyzed. A total of 454 residency program directors completed the study (response rate, 46.4%). The majority of respondents were women (58.8%), were members of Generation X (75.4%), and worked in a hospital or health system (80%). Most respondents (73%) rated themselves as either nonusers or novice users of social media. Twenty percent indicated that they had viewed a pharmacy residency applicant's social media information. More than half (52%) had encountered e-professionalism issues, including questionable photos and posts revealing unprofessional attitudes, and 89% strongly agreed or agreed that information voluntarily published online was fair game for judgments on character, attitudes, and professionalism. Only 4% of respondents had reviewed applicants' profiles for residency selection decisions. Of those respondents, 52% indicated that the content had no effect on resident selection. Over half of residency program directors were unsure whether they will use social media information for future residency selection decisions. Residency program directors from different generations had different views regarding social media information and its use in residency applicant selections. Residency program directors anticipated using social media information to aid in future decisions for resident selection and hiring.

Modeling Hourly Resident Productivity in the Emergency Department.

Science.gov (United States)

Joseph, Joshua W; Henning, Daniel J; Strouse, Connie S; Chiu, David T; Nathanson, Larry A; Sanchez, Leon D

2017-08-01

Resident productivity, defined as new patients per hour, carries important implications for emergency department operations. In high-volume academic centers, essential staffing decisions can be made on the assumption that residents see patients at a static rate. However, it is unclear whether this model mirrors reality; previous studies have not rigorously examined whether productivity changes over time. We examine residents' productivity across shifts to determine whether it remained consistent. This was a retrospective cohort study conducted in an urban academic hospital with a 3-year emergency medicine training program in which residents acquire patients ad libitum throughout their shift. Time stamps of all patient encounters were automatically logged. A linear mixed model was constructed to predict productivity per shift hour. A total of 14,364 8- and 9-hour shifts were worked by 75 residents between July 1, 2010, and June 20, 2015. This comprised 6,127 (42.7%) postgraduate year (PGY) 1 shifts, 7,236 (50.4%) PGY-2 shifts, and 998 (6.9%) PGY-3 nonsupervisory shifts (Table 1). Overall, residents treated a mean of 10.1 patients per shift (SD 3.2), with most patients at Emergency Severity Index level 3 or more acute (93.8%). In the initial hour, residents treated a mean of 2.14 patients (SD 1.2), and every subsequent hour was associated with a significant decrease, with the largest in the second, third, and final hours. Emergency medicine resident productivity during a single shift follows a reliable pattern that decreases significantly hourly, a pattern preserved across PGY years and types of shifts. This suggests that resident productivity is a dynamic process, which should be considered in staffing decisions and studied further. Copyright © 2016 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

Practice management education during surgical residency.

Science.gov (United States)

Jones, Kory; Lebron, Ricardo A; Mangram, Alicia; Dunn, Ernest

2008-12-01

Surgical education has undergone radical changes in the past decade. The introductions of laparoscopic surgery and endovascular techniques have required program directors to alter surgical training. The 6 competencies are now in place. One issue that still needs to be addressed is the business aspect of surgical practice. Often residents complete their training with minimal or no knowledge on coding of charges or basic aspects on how to set up a practice. We present our program, which has been in place over the past 2 years and is designed to teach the residents practice management. The program begins with a series of 10 lectures given monthly beginning in August. Topics include an introduction to types of practices available, negotiating a contract, managed care, and marketing the practice. Both medical and surgical residents attend these conferences. In addition, the surgical residents meet monthly with the business office to discuss billing and coding issues. These are didactic sessions combined with in-house chart reviews of surgical coding. The third phase of the practice management plan has the coding team along with the program director attend the outpatient clinic to review in real time the evaluation and management coding of clinic visits. Resident evaluations were completed for each of the practice management lectures. The responses were recorded on a Likert scale. The scores ranged from 4.1 to 4.8 (average, 4.3). Highest scores were given to lectures concerning negotiating employee agreements, recruiting contracts, malpractice insurance, and risk management. The medical education department has tracked resident coding compliance over the past 2 years. Surgical coding compliance increased from 36% to 88% over a 12-month period. The program director who participated in the educational process increased his accuracy from 50% to 90% over the same time period. When residents finish their surgical training they need to be ready to enter the world of business

Spectrum analysis of radiotracer residence time distribution for industrial and environmental applications

International Nuclear Information System (INIS)

Kasban, H.; Ashraf Hamid

2014-01-01

Radiotracer signal analysis and recognition still represents challenges in industrial and environmental applications specially in residence time distribution (RTD) measurement. This paper presents a development for the RTD signal recognition method that is based on power density spectrum (PDS). In this development, the features are extracted from the signals and/or from their higher-orders statistics (HOS) (Bispectrum and Trispectrum) instead of PDS. The HOS are estimated using direct, indirect and parametric estimations. The recognition results are analyzed and compared for different HOS estimation in order to select the best HOS estimation method for the purpose of RTD signal recognition. The artificial neural networks are used for training and testing of the proposed method. The proposed method is tested using RTD signals obtained from the measurements carried out using radiotracer technique. The simulation results show that the parametric estimation of the Trispectrum gives the higher recognition rate and is the most reliable for the RTD signal recognition. (author)

Curricula and Organization of Primary Care Residencies in Internal Medicine.

Science.gov (United States)

Eisenberg, John M.

1980-01-01

The organization and curricula of internal medicine residencies programs that emphasize primary care are described and compared with traditional residencies in internal medicine. It is noted that primary care residents spend more time in ambulatory care and are allowed more electives in specialties outside of internal medicine. Out-of-hospital…

The State of Communication Education in Family Medicine Residencies.

Science.gov (United States)

Jansen, Kate L; Rosenbaum, Marcy E

2016-06-01

Communication skills are essential to medical training and have lasting effects on patient satisfaction and adherence rates. However, relatively little is reported in the literature identifying how communication is taught in the context of residency education. Our goal was to determine current practices in communication curricula across family medicine residency programs. Behavioral scientists and program directors in US family medicine residencies were surveyed via email and professional organization listservs. Questions included whether programs use a standardized communication model, methods used for teaching communication, hours devoted to teaching communication, as well as strengths and areas for improvement in their program. Analysis identified response frequencies and ranges complemented by analysis of narrative comments. A total of 204 programs out of 458 family medicine residency training sites responded (45%), with 48 out of 50 US states represented. The majority of respondents were behavioral scientists. Seventy-five percent of programs identified using a standard communication model; Mauksch's patient-centered observation model (34%) was most often used. Training programs generally dedicated more time to experiential teaching methods (video review, work with simulated patients, role plays, small groups, and direct observation of patient encounters) than to lectures (62% of time and 24% of time, respectively). The amount of time dedicated to communication education varied across programs (average of 25 hours per year). Respondent comments suggest that time dedicated to communication education and having a formal curriculum in place are most valued by educators. This study provides a picture of how communication skills teaching is conducted in US family medicine residency programs. These findings can provide a comparative reference and rationale for residency programs seeking to evaluate their current approaches to communication skills teaching and

Devolatilization kinetics of woody biomass at short residence times and high heating rates and peak temperatures

DEFF Research Database (Denmark)

Johansen, Joakim M.; Gadsbøll, Rasmus; Thomsen, Jesper

2016-01-01

This work combines experimental and computational fluid dynamics (CFD) results to derive global kinetics for biomass (pine wood) devolatilization during heating rates on the order of 105Ks-1, bulk flow peak temperatures between 1405 and 1667K, and particle residence times below 0.1s. Experiments......Jmol-1. The accuracy of the derived global kinetics was supported by comparing predictions to experimental results from a 15kW furnace. The work emphasizes the importance of characterizing the temperature history of the biomass particles when deriving pyrolysis kinetics. The present results indicate...

Impact of meander geometry and stream flow events on residence times and solute transport in the intra-meander flow

Science.gov (United States)

Nasir Mahmood, Muhammad; Schmidt, Christian; Trauth, Nico

2017-04-01

Stream morphological features, in combination with hydrological variability play a key role in water and solute exchange across surface and subsurface waters. Meanders are prominent morphological features within stream systems which exhibit unique hydrodynamics. The water surface elevation difference across the inner bank of a meander induces lateral hyporheic exchange within the intra-meander region. This hyporheic flow is characterized by considerably prolonged flow paths and residence times (RT) compared to smaller scales of hyporheic exchange. In this study we examine the impact of different meander geometries on the intra-meander hyporheic flow field and solute mobilization under both steady state and transient flow conditions. We developed a number of artificial meander shape scenarios, representing various meander evolution stages, ranging from a typical initial to advanced stage (near cut off ) meander. Three dimensional steady state numerical groundwater flow simulations including the unsaturated zone were performed for the intra-meander region. The meandering stream was implemented in the model by adjusting the top layers of the modelling domain to the streambed elevation and assigning linearly decreasing head boundary conditions to the streambed cells. Residence times for the intra-meander region were computed by advective particle tracking across the inner bank of meander. Selected steady state cases were extended to transient flow simulations to evaluate the impact of stream discharge events on the temporal behavior of the water exchange and solute transport in the intra-meander region. The transient stream discharge was simulated for a number of discharge events of variable duration and peak height using the surface water model HEC-RAS. Transient hydraulic heads obtained from the surface water model were applied as transient head boundary conditions to the streambed cells of the groundwater model. A solute concentration source was added in the

Real-Time Observation of Apathy in Long-Term Care Residents With Dementia: Reliability of the Person-Environment Apathy Rating Scale.

Science.gov (United States)

Jao, Ying-Ling; Mogle, Jacqueline; Williams, Kristine; McDermott, Caroline; Behrens, Liza

2018-04-01

Apathy is prevalent in individuals with dementia. Lack of responsiveness to environmental stimulation is a key characteristic of apathy. The Person-Environment Apathy Rating (PEAR) scale consists of environment and apathy subscales, which allow for examination of environmental impact on apathy. The interrater reliability of the PEAR scale was examined via real-time observation. The current study included 45 observations of 15 long-term care residents with dementia. Each participant was observed at three time points for 10 minutes each. Two raters observed the participant and surrounding environment and independently rated the participant's apathy and environmental stimulation using the PEAR scale. Weighted Kappa was 0.5 to 0.82 for the PEAR-Environment subscale and 0.5 to 0.8 for the PEAR-Apathy subscale. Overall, with the exception of three items with relatively weak reliability (0.50 to 0.56), the PEAR scale showed moderate to strong interrater reliability (0.63 to 0.82). The results support the use of the PEAR scale to measure environmental stimulation and apathy via real-time observation in long-term care residents with dementia. [Journal of Gerontological Nursing, 44(4), 23-28.]. Copyright 2018, SLACK Incorporated.

Comparison of Emergency Medicine Malpractice Cases Involving Residents to Non-Resident Cases.

Science.gov (United States)

Gurley, Kiersten L; Grossman, Shamai A; Janes, Margaret; Yu-Moe, C Winnie; Song, Ellen; Tibbles, Carrie D; Shapiro, Nathan I; Rosen, Carlo L

2018-04-17

Data are lacking on how emergency medicine (EM) malpractice cases with resident involvement differs from cases that do not name a resident. To compare malpractice case characteristics in cases where a resident is involved (resident case) to cases that do not involve a resident (non-resident case) and to determine factors that contribute to malpractice cases utilizing EM as a model for malpractice claims across other medical specialties. We used data from the Controlled Risk Insurance Company (CRICO) Strategies' division Comparative Benchmarking System (CBS) to analyze open and closed EM cases asserted from 2009-2013. The CBS database is a national repository that contains professional liability data on > 400 hospitals and > 165,000 physicians, representing over 30% of all malpractice cases in the U.S (> 350,000 claims). We compared cases naming residents (either alone or in combination with an attending) to those that did not involve a resident (non-resident cohort). We reported the case statistics, allegation categories, severity scores, procedural data, final diagnoses and contributing factors. Fisher's exact test or t-test was used for comparisons (alpha set at 0.05). Eight hundred and forty-five EM cases were identified of which 732 (87%) did not name a resident (non-resident cases), while 113 (13%) included a resident (resident cases) (Figure 1). There were higher total incurred losses for non-resident cases (Table 1). The most frequent allegation categories in both cohorts were "Failure or Delay in Diagnosis/Misdiagnosis" and "Medical Treatment" (non-surgical procedures or treatment regimens i.e. central line placement). Allegation categories of Safety and Security, Patient Monitoring, Hospital Policy and Procedure and Breach of Confidentiality were found in the non-resident cases. Resident cases incurred lower payments on average ($51,163 vs. $156,212 per case). Sixty six percent (75) of resident vs 57% (415) of non-resident cases were high severity claims

SACCHARIFICATION OF NATIVE CASSAVA STARCH AT HIGH DRY SOLIDS IN AN ENZYMATIC MEMBRANE REACTOR

Directory of Open Access Journals (Sweden)

I Nyoman Widiasa

2012-02-01

Full Text Available This study is aimed to develop a novel process scheme for hydrolysis of native cassava starch at high dry solids using an enzymatic membrane reactor (EMR. Firstly, liquefied cassava starch having solids content up to 50% by weight was prepared by three stage liquefactions in a conventional equipment using a commercially available heat stable a-amylase (Termamyl 120L. The liquefied cassava starch was further saccharified in an EMR using glucoamylase (AMG E. By using the developed process scheme, a highly clear hydrolysate with dextrose equivalent (DE approximately 97 could be produced, provided the increase of solution viscosity during the liquefaction was precisely controlled. The excessive space time could result in reduction in conversion degree of starch. Moreover, a residence time distribution study confirmed that the EMR could be modelled as a simple continuous stirred tank reactor (CSTR. Using Lineweaver-Burk analysis, the apparent Michaelis-Menten constant (Km and glucose production rate constant (k2 were 552 (g/l and 4.04 (min-1, respectively. Application of simple CSTR model with those kinetic parameters was quietly appropriate to predict the reactor’s performance at low space time.

Teacher in Residence: Bringing Science to Students

CERN Multimedia

Daisy Yuhas

CERN welcomes its first Teacher in Residence, Terrence Baine of the University of Oslo. Baine, who originally hails from Canada, will be concurrently completing his PhD in Physics Education during his time at CERN. Like CERN’s High School Teacher Programme (HST), of which Baine is an alumnus, the Teacher in Residence position is designed to help educators spread the science of CERN in a form that is accessible to students and can encourage them to pursue physics throughout their education.   Terrence Baine, first 'teacher in residence' at CERN Baine explains, “It’s very important to have a teacher present who can be that middle person between the young peoplecoming here, whom we are trying to enlighten, and the physicists who work at CERN. The Teacher in Residence can act as an on-site educational consultant.” As Teacher in Residence, Baine’s primary project will be to develop teaching modules, or a series of lesson plans, that can help high schoo...

Otolaryngology Residency Program Research Resources and Scholarly Productivity.

Science.gov (United States)

Villwock, Jennifer A; Hamill, Chelsea S; Nicholas, Brian D; Ryan, Jesse T

2017-06-01

Objective To delineate research resources available to otolaryngology residents and their impact on scholarly productivity. Study Design Survey of current otolaryngology program directors. Setting Otolaryngology residency programs. Subjects and Methods An anonymous web-based survey was sent to 98 allopathic otolaryngology training program directors. Fisher exact tests and nonparametric correlations were used to determine statistically significant differences among various strata of programs. Results Thirty-nine percent (n = 38) of queried programs responded. Fourteen (37%) programs had 11 to 15 full-time, academic faculty associated with the residency program. Twenty (53%) programs have a dedicated research coordinator. Basic science lab space and financial resources for statistical work were present at 22 programs (58%). Funding is uniformly provided for presentation of research at conferences; a minority of programs (13%) only funded podium presentations. Twenty-four (63%) have resident research requirements beyond the Accreditation Council for Graduate Medical Education (ACGME) mandate of preparing a "manuscript suitable for publication" prior to graduation. Twenty-five (67%) programs have residents with 2 to 3 active research projects at any given time. None of the investigated resources were significantly associated with increased scholarly output. There was no uniformity to research curricula. Conclusions Otolaryngology residency programs value research, evidenced by financial support provided and requirements beyond the ACGME minimum. Additional resources were not statistically related to an increase in resident research productivity, although they may contribute positively to the overall research experience during training. Potential future areas to examine include research curricula best practices, how to develop meaningful mentorship and resource allocation that inspires continued research interest, and intellectual stimulation.

Residents' experiences of abuse, discrimination and sexual harassment during residency training. McMaster University Residency Training Programs.

Science.gov (United States)

Cook, D J; Liutkus, J F; Risdon, C L; Griffith, L E; Guyatt, G H; Walter, S D

1996-06-01

To assess the prevalence of psychological abuse, physical assault, and discrimination on the basis of gender and sexual orientation, and to examine the prevalence and impact of sexual harassment in residency training programs. Self-administered questionnaire. McMaster University, Hamilton, Ont. Residents in seven residency training programs during the academic year from July 1993 to June 1994. Of 225 residents 186 (82.7%) returned a completed questionnaire, and 50% of the respondents were women. Prevalence of psychological abuse, physical assault and discrimination on the basis of gender and sexual orientation experienced by residents during medical training, prevalence and residents' perceived frequency of sexual harassment. Psychological abuse was reported by 50% of the residents. Some of the respondents reported physical assault, mostly by patients and their family members (14.7% reported assaults by male patients and family members, 9.8% reported assaults by female patients and family members), 5.4% of the female respondents reported assault by male supervising physicians. Discrimination on the basis of gender was reported to be common and was experienced significantly more often by female residents than by male residents (p sexual orientation. Most of the respondents experienced sexual harassment, especially in the form of sexist jokes, flirtation and unwanted compliments on their dress or figure. On average, 40% of the respondents, especially women (p sexual harassment to someone (p sexual harassment were embarassment (reported by 24.0%), anger (by 23.4%) and frustration (20.8%). Psychological abuse, discrimination on the basis of gender and sexual harassment are commonly experienced by residents in training programs. A direct, progressive, multidisciplinary approach is needed to label and address these problems.

Burnout, engagement and resident physicians' self-reported errors.

Science.gov (United States)

Prins, J T; van der Heijden, F M M A; Hoekstra-Weebers, J E H M; Bakker, A B; van de Wiel, H B M; Jacobs, B; Gazendam-Donofrio, S M

2009-12-01

Burnout is a work-related syndrome that may negatively affect more than just the resident physician. On the other hand, engagement has been shown to protect employees; it may also positively affect the patient care that the residents provide. Little is known about the relationship between residents' self-reported errors and burnout and engagement. In our national study that included all residents and physicians in The Netherlands, 2115 questionnaires were returned (response rate 41.1%). The residents reported on burnout (Maslach Burnout Inventory-Health and Social Services), engagement (Utrecht Work Engagement Scale) and self-assessed patient care practices (six items, two factors: errors in action/judgment, errors due to lack of time). Ninety-four percent of the residents reported making one or more mistake without negative consequences for the patient during their training. Seventy-one percent reported performing procedures for which they did not feel properly trained. More than half (56%) of the residents stated they had made a mistake with a negative consequence. Seventy-six percent felt they had fallen short in the quality of care they provided on at least one occasion. Men reported more errors in action/judgment than women. Significant effects of specialty and clinical setting were found on both types of errors. Residents with burnout reported significantly more errors (p engaged residents reported fewer errors (p burnout and to keep residents engaged in their work.

[Fire behavior of Mongolian oak leaves fuel bed under no-wind and zero-slope conditions. II. Analysis of the factors affecting flame length and residence time and related prediction models].

Science.gov (United States)

Zhang, Ji-Li; Liu, Bo-Fei; Di, Xue-Ying; Chu, Teng-Fei; Jin, Sen

2012-11-01

Taking fuel moisture content, fuel loading, and fuel bed depth as controlling factors, the fuel beds of Mongolian oak leaves in Maoershan region of Northeast China in field were simulated, and a total of one hundred experimental burnings under no-wind and zero-slope conditions were conducted in laboratory, with the effects of the fuel moisture content, fuel loading, and fuel bed depth on the flame length and its residence time analyzed and the multivariate linear prediction models constructed. The results indicated that fuel moisture content had a significant negative liner correlation with flame length, but less correlation with flame residence time. Both the fuel loading and the fuel bed depth were significantly positively correlated with flame length and its residence time. The interactions of fuel bed depth with fuel moisture content and fuel loading had significant effects on the flame length, while the interactions of fuel moisture content with fuel loading and fuel bed depth affected the flame residence time significantly. The prediction model of flame length had better prediction effect, which could explain 83.3% of variance, with a mean absolute error of 7.8 cm and a mean relative error of 16.2%, while the prediction model of flame residence time was not good enough, which could only explain 54% of variance, with a mean absolute error of 9.2 s and a mean relative error of 18.6%.

Co-hydrothermal treatment of fallen leaves with iron sludge to prepare magnetic iron product and solid fuel.

Science.gov (United States)

Gu, Lin; Li, Binglian; Wen, Haifeng; Zhang, Xin; Wang, Liang; Ye, Jianfeng

2018-06-01

The hydrothermal carbonization (HTC) was performed on Metasequoia Leaves (ML) in the presence of iron sludge, both of which were generated as solid residuals. The relations between sludge, char's properties and operating conditions were systemically investigated. Iron sludge primarily catalyzed the efficient formation of char with higher heating value (HHV) becoming 1.15-1.65 times of ML (18.21 MJ/kg) and was meanwhile reduced to magnetite. The hydrated Fe ions in octahedron crystals acted as nucleophiles facilitating the dehydration and decarboxylation reactions. The increased HHV is found strong temperature dependent while prolonging the residence time is more preferable for low organic acids generation. Thermogravimetric analysis confirmed the iron sludge enhanced conversion of volatile to fixed carbon. The as-prepared solid char showed better stability after catalytic HTC treatment, having ignition temperature increased from 253 to 426 °C as compared to the char prepared without iron sludge addition. Copyright © 2018 Elsevier Ltd. All rights reserved.

Anesthesiology resident personality type correlates with faculty assessment of resident performance.

Science.gov (United States)

Schell, Randall M; Dilorenzo, Amy N; Li, Hsin-Fang; Fragneto, Regina Y; Bowe, Edwin A; Hessel, Eugene A

2012-11-01

To study the association between anesthesiology residents' personality preference types, faculty evaluations of residents' performance, and knowledge. Convenience sample and prospective study. Academic department of anesthesiology. Consenting anesthesiology residents (n = 36). All participants completed the Myers Briggs Type Indicator® (MBTI®). All residents' 6-month summation of daily focal evaluations completed by faculty [daily performance score (DPS); 1 = unsatisfactory, 2 = needs improvement, 3 = meets expectations, 4 = exceeds expectations], as well as a global assessment of performance (GAP) score based on placement of each resident into perceived quartile compared with their peers (ie,1 = first, or top, quartile) by senior faculty (n = 7) who also completed the MBTI, were obtained. The resident MBTI personality preferences were compared with the DPS and GAP scores, the United States Medical Licensing Examination (USMLE) I and II scores, and faculty MBTI personality type. There was no association between personality preference type and performance on standardized examinations (USMLE I, II). The mean GAP score was better (higher quartile score) for Extraverts than Introverts (median 2.0 vs 2.6, P = 0.0047) and for Sensing versus Intuition (median 2.0 vs 2.6, P = 0.0206) preference. Faculty evaluator MBTI preference type did not influence the GAP scores they assigned residents. Like GAP, the DPS was better for residents with Sensing versus Intuition preference (median 3.5 vs 3.3, P = 0.0111). No difference in DPS was noted between Extraverts and Introverts. Personality preference type was not associated with resident performance on standardized examinations, but it was associated with faculty evaluations of resident performance. Residents with Sensing personality preference were evaluated more favorably on global and focal faculty evaluations than those residents who chose the Intuition preference. Extraverted residents were evaluated more favorably on

Evaluation of quantitative imaging methods for organ activity and residence time estimation using a population of phantoms having realistic variations in anatomy and uptake

International Nuclear Information System (INIS)

He Bin; Du Yong; Segars, W. Paul; Wahl, Richard L.; Sgouros, George; Jacene, Heather; Frey, Eric C.

2009-01-01

Estimating organ residence times is an essential part of patient-specific dosimetry for radioimmunotherapy (RIT). Quantitative imaging methods for RIT are often evaluated using a single physical or simulated phantom but are intended to be applied clinically where there is variability in patient anatomy, biodistribution, and biokinetics. To provide a more relevant evaluation, the authors have thus developed a population of phantoms with realistic variations in these factors and applied it to the evaluation of quantitative imaging methods both to find the best method and to demonstrate the effects of these variations. Using whole body scans and SPECT/CT images, organ shapes and time-activity curves of 111In ibritumomab tiuxetan were measured in dosimetrically important organs in seven patients undergoing a high dose therapy regimen. Based on these measurements, we created a 3D NURBS-based cardiac-torso (NCAT)-based phantom population. SPECT and planar data at realistic count levels were then simulated using previously validated Monte Carlo simulation tools. The projections from the population were used to evaluate the accuracy and variation in accuracy of residence time estimation methods that used a time series of SPECT and planar scans. Quantitative SPECT (QSPECT) reconstruction methods were used that compensated for attenuation, scatter, and the collimator-detector response. Planar images were processed with a conventional (CPlanar) method that used geometric mean attenuation and triple-energy window scatter compensation and a quantitative planar (QPlanar) processing method that used model-based compensation for image degrading effects. Residence times were estimated from activity estimates made at each of five time points. The authors also evaluated hybrid methods that used CPlanar or QPlanar time-activity curves rescaled to the activity estimated from a single QSPECT image. The methods were evaluated in terms of mean relative error and standard deviation of the

A model of environmental behaviour of contaminated dust and its application to determining dust fluxes and residence times

International Nuclear Information System (INIS)

Allott, R.W.; Kelly, M.; Hewitt, C.N.

1994-01-01

A model has been developed to describe the temporal behaviour of the concentrations of a pollutant tracer within the urban environment of Barrow-in-Furness, NW England. The tracer used was 137 Cs derived primarily from wet deposition of the radioactive cloud from the Chernobyl reactor accident. The 137 Cs activity deposited during this primary event was supplemented by a small secondary atmospheric deposition input of resuspended activity. The model was validated against the measured temporal behaviour of 137 Cs in urban dust for two outdoor reservoirs in which the only observed input of dust and activity was by atmospheric deposition. Further modelling studies on other reservoirs (both outdoors and indoors) confirmed the existence of additional input influxes of dust and activity. The model enabled estimates of the magnitudes of these additional fluxes to be made and mean dust mass residence times to be calculated. These residence times correspond to environment half-lives of 170 ± 70 d outdoors and 20 ± 1 d indoors, for reservoirs which only receive a single primary input of a contaminant. Where secondary inputs of pollutants occur, the mean environmental half-lives of the pollutants increase by 50% for outdoor dust reservoirs and over 18-times for indoor reservoirs. This re-contamination of indoor dusts has implications in that attention should be paid to reducing outdoor contamination levels to ensure that attempts to reduce the levels of a pollutant indoors by cleaning are effective. (Author)

Solid - solid and solid - liquid phase transitions of iron and iron alloys under laser shock compression

Science.gov (United States)

Harmand, M.; Krygier, A.; Appel, K.; Galtier, E.; Hartley, N.; Konopkova, Z.; Lee, H. J.; McBride, E. E.; Miyanishi, K.; Nagler, B.; Nemausat, R.; Vinci, T.; Zhu, D.; Ozaki, N.; Fiquet, G.

2017-12-01

An accurate knowledge of the properties of iron and iron alloys at high pressures and temperatures is crucial for understanding and modelling planetary interiors. While Earth-size and Super-Earth Exoplanets are being discovered in increasingly large numbers, access to detailed information on liquid properties, melting curves and even solid phases of iron and iron at the pressures and temperatures of their interiors is still strongly limited. In this context, XFEL sources coupled with high-energy lasers afford unique opportunities to measure microscopic structural properties at far extreme conditions. Also the achievable time resolution allows the shock history and phase transition mechanisms to be followed during laser compression, improving our understanding of the high pressure and high strain experiments. Here we present recent studies devoted to investigate the solid-solid and solid-liquid transition in laser-shocked iron and iron alloys (Fe-Si, Fe-C and Fe-O alloys) using X-ray diffraction and X-ray diffuse scattering. Experiment were performed at the MEC end-station of the LCLS facility at SLAC (USA). Detection of the diffuse scattering allowed the identification of the first liquid peak position along the Hugoniot, up to 4 Mbar. The time resolution shows ultrafast (between several tens and several hundreds of picoseconds) solid-solid and solid-liquid phase transitions. Future developments at XFEL facilities will enable detailed studies of the solid and liquid structures of iron and iron alloys as well as out-of-Hugoniot studies.

Measuring resident well-being: impostorism and burnout syndrome in residency.

Science.gov (United States)

Legassie, Jenny; Zibrowski, Elaine M; Goldszmidt, Mark A

2008-07-01

Assessing resident well-being is becoming increasingly important from a programmatic standpoint. Two measures that have been used to assess this are the Clance Impostor Scale (CIS) and the Maslach Burnout Inventory-Human Services Survey (MBI-HSS). However, little is known about the relationship between the two phenomena. To explore the prevalence and association between impostorism and burnout syndrome in a sample of internal medicine residents. Anonymous, cross-sectional postal survey. Forty-eight internal medicine residents (postgraduate year [PGY] 1-3) at the Schulich School of Medicine & Dentistry (62.3% response rate). Short demographic questionnaire, CIS and MBI-HSS. Impostorism and burnout syndrome were identified in 43.8% and 12.5% of residents, respectively. With the exception of a negative correlation between CIS scores and the MBI's personal accomplishment subscale (r = -.30; 95% CI -.54 to -.02), no other significant relations were identified. Foreign-trained residents were more likely to score as impostors (odds ratio [OR] 10.7; 95% CI 1.2 to 98.2) while senior residents were more likely to experience burnout syndrome (OR 16.5 95% CI 1.6 to 168.5). Both impostorism and burnout syndrome appear to be threats to resident well-being in our program. The lack of relationship between the two would suggest that programs and researchers wishing to address the issue of resident distress should consider using both measures. The finding that foreign-trained residents appear to be more susceptible to impostorism warrants further study.

Fluidization behavior in a circulating slugging fluidized bed reactor. Part I : residence time and residence time distribution of polyethylene solids

NARCIS (Netherlands)

Putten, van I.C.; Sint Annaland, van M.; Weickert, G.

2007-01-01

Square nosed slugging fluidization behavior in a circulating fluidized bed riser using a polyethylene powder with a very wide particle size distribution was studied. In square nosed slugging fluidization the extent of mixing of particles of different size depends on the riser diameter, gas velocity,

Fluidization behavior in a circulating slugging fluidized bed reactor. Part I: Residence time and residence time distribution of polyethylene solids

NARCIS (Netherlands)

van Putten, I.C.; van Sint Annaland, M.; Weickert, G.

2007-01-01

Square nosed slugging fluidization behavior in a circulating fluidized bed riser using a polyethylene powder with a very wide particle size distribution was studied. In square nosed slugging fluidization the extent of mixing of particles of different size depends on the riser diameter, gas velocity,

New Media for Educating Urology Residents: An Interview Study in Canada and Germany.

Science.gov (United States)

Salem, Johannes; Borgmann, Hendrik; MacNeily, Andrew; Boehm, Katharina; Schmid, Marianne; Groeben, Christer; Baunacke, Martin; Huber, Johannes

To investigate the usage and perceived usefulness of new media for educating urology residents in Canada and Germany. We designed an 11-item online survey to assess the use and perceived usefulness of new media for education. We performed a comparative analysis. The survey was distributed via e-mail to 143 Canadian and 721 German urology residents. The survey included 58 urology residents from Canada and 170 from Germany. A total of 58 residents from Canada (41% response rate) and 170 from Germany (24% response rate) responded to this survey. Residents spent 45% of their education time on new media. The Internet was used by 91% (n = 208) of the residents for professional education purposes, with a median time of 270 minutes (interquartile range [IQR]: 114-540) per month. Apps were used by 54% (n = 118) of the residents, with a median time of 101 minutes (IQR: 45-293) per month. A total of 23% (n = 47) of the residents used social media (SoMe) for education, with a median time of 90 minutes (IQR: 53-80) per month. In all, 100% (n = 228) rated the Internet, 76% (n = 173) apps, and 43% (n = 97) SoMe as being useful for professional education purposes. A total of 90% (n = 205) watched medical videos for education, and 89% (n = 203) of these videos were on surgical procedures. Canadian urology residents used more new media sources for professional education than did the Germans (58% vs. 41%, p media was higher among Canadian residents for the Internet (p media play a dominant role in the education of urology residents. The primary source for personal education in urology is the Internet. Future studies and technological developments should investigate and improve new media tools to optimize education during residency. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

A passive heat tracer experiment to determine the seasonal variation in residence times in a managed aquifer recharge system with DTS

NARCIS (Netherlands)

des Tombe, B.F.; Bakker, M.; Schaars, F; van der Made, KJ; Calje, R; Borst, L.

2016-01-01

Targeted provisional session N°8.01 The seasonal variation in residence times is determined in a managed aquifer recharge system using a passive heat tracer test. The managed aquifer recharge system consists of a sequence of alternating elongated recharge basins and rows of recovery wells. The

Applying Expectancy Theory to residency training: proposing opportunities to understand resident motivation and enhance residency training

Directory of Open Access Journals (Sweden)

Shweiki E

2015-04-01

Full Text Available Ehyal Shweiki,1 Niels D Martin,2 Alec C Beekley,1 Jay S Jenoff,1 George J Koenig,1 Kris R Kaulback,1 Gary A Lindenbaum,1 Pankaj H Patel,1 Matthew M Rosen,1 Michael S Weinstein,1 Muhammad H Zubair,2 Murray J Cohen1 1Department of Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, USA; 2Department of Surgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA Abstract: Medical resident education in the United States has been a matter of national priority for decades, exemplified initially through the Liaison Committee for Graduate Medical Education and then superseded by the Accreditation Council for Graduate Medical Education. A recent Special Report in the New England Journal of Medicine, however, has described resident educational programs to date as prescriptive, noting an absence of innovation in education. Current aims of contemporary medical resident education are thus being directed at ensuring quality in learning as well as in patient care. Achievement and work-motivation theories attempt to explain people's choice, performance, and persistence in tasks. Expectancy Theory as one such theory was reviewed in detail, appearing particularly applicable to surgical residency training. Correlations between Expectancy Theory as a work-motivation theory and residency education were explored. Understanding achievement and work-motivation theories affords an opportunity to gain insight into resident motivation in training. The application of Expectancy Theory in particular provides an innovative perspective into residency education. Afforded are opportunities to promote the development of programmatic methods facilitating surgical resident motivation in education. Keywords: learning, education, achievement

The costs and quality of operative training for residents in tympanoplasty type I.

Science.gov (United States)

Wang, Mao-Che; Yu, Eric Chen-Hua; Shiao, An-Suey; Liao, Wen-Huei; Liu, Chia-Yu

2009-05-01

A teaching hospital would incur more operation room costs on training surgical residents. To evaluate the increased operation time and the increased operation room costs of operations performed by surgical residents. As a model we used a very common surgical otology procedure -- tympanoplasty type I. From January 1, 2004 to December 31, 2004, we included in this study 100 patients who received tympanoplasty type I in Taipei Veterans General Hospital. Fifty-six procedures were performed by a single board-certified surgeon and 44 procedures were performed by residents. We analyzed the operation time and surgical outcomes in these two groups of patients. The operation room cost per minute was obtained by dividing the total operation room expenses by total operation time in the year 2004. The average operation time of residents was 116.47 min, which was significantly longer (pcost USD $40.36 more for each operation performed by residents in terms of operation room costs. The surgical success rate of residents was 81.82%, which was significantly lower (p=0.016) than that of the board-certified surgeon (96.43%).

Time resolved resonant inelastic X-ray scattering: A supreme tool to understand dynamics in solids and molecules

International Nuclear Information System (INIS)

Beye, M.; Wernet, Ph.; Schüßler-Langeheine, C.; Föhlisch, A.

2013-01-01

Highlights: •The high specificity of RIXS ideally suits time-resolved measurements. •Methods relating to the core hole lifetime cover the low femtosecond regime. •Pump-probe methods are used starting at sub-ps time scales. •FELs and synchrotrons are useful for pump-probe studies. •Examples from solid state dynamics and molecules are discussed. -- Abstract: Dynamics in materials typically involve different degrees of freedom, like charge, lattice, orbital and spin in a complex interplay. Time-resolved resonant inelastic X-ray scattering (RIXS) as a highly selective tool can provide unique insight and follow the details of dynamical processes while resolving symmetries, chemical and charge states, momenta, spin configurations, etc. In this paper, we review examples where the intrinsic scattering duration time is used to study femtosecond phenomena. Free-electron lasers access timescales starting in the sub-ps range through pump-probe methods and synchrotrons study the time scales longer than tens of ps. In these examples, time-resolved resonant inelastic X-ray scattering is applied to solids as well as molecular systems

Does Residency Selection Criteria Predict Performance in Orthopaedic Surgery Residency?

Science.gov (United States)

Raman, Tina; Alrabaa, Rami George; Sood, Amit; Maloof, Paul; Benevenia, Joseph; Berberian, Wayne

2016-04-01

More than 1000 candidates applied for orthopaedic residency positions in 2014, and the competition is intense; approximately one-third of the candidates failed to secure a position in the match. However, the criteria used in the selection process often are subjective and studies have differed in terms of which criteria predict either objective measures or subjective ratings of resident performance by faculty. Do preresidency selection factors serve as predictors of success in residency? Specifically, we asked which preresidency selection factors are associated or correlated with (1) objective measures of resident knowledge and performance; and (2) subjective ratings by faculty. Charts of 60 orthopaedic residents from our institution were reviewed. Preresidency selection criteria examined included United States Medical Licensing Examination (USMLE) Step 1 and Step 2 scores, Medical College Admission Test (MCAT) scores, number of clinical clerkship honors, number of letters of recommendation, number of away rotations, Alpha Omega Alpha (AOA) honor medical society membership, fourth-year subinternship at our institution, and number of publications. Resident performance was assessed using objective measures including American Board of Orthopaedic Surgery (ABOS) Part I scores and Orthopaedics In-Training Exam (OITE) scores and subjective ratings by faculty including global evaluation scores and faculty rankings of residents. We tested associations between preresidency criteria and the subsequent objective and subjective metrics using linear correlation analysis and Mann-Whitney tests when appropriate. Objective measures of resident performance namely, ABOS Part I scores, had a moderate linear correlation with the USMLE Step 2 scores (r = 0.55, p communication skills" subsection of the global evaluations. We found that USMLE Step 2, number of honors in medical school clerkships, and AOA membership demonstrated the strongest correlations with resident performance. Our

General surgery residents improve efficiency but not outcome of trauma care.

Science.gov (United States)

Offner, Patrick J; Hawkes, Allison; Madayag, Robert; Seale, Fred; Maines, Charles

2003-07-01

Current American College of Surgeons Level I trauma center verification requires the presence of a residency program in which trauma care is an integral part of the training. The rationale for this requirement remains unclear, with no scientific evidence that resident participation improves the quality of trauma care. The purpose of this study was to determine whether quality or efficiency of trauma care is influenced by general surgery residents. Our urban Level I trauma center has traditionally used 24-hour in-house postgraduate year-4 general surgery residents in conjunction with at-home trauma attending backup to provide trauma care. As of July 1, 2000, general surgery residents no longer participated in trauma patient care, leaving sole responsibility to an in-house trauma attending. Data regarding patient outcome and resource use with and without surgery resident participation were tabulated and analyzed. Continuous data were compared using Student's t test if normally distributed and the Mann-Whitney U test if nonparametric. Categorical data were compared using chi2 analysis or Fisher's exact test as appropriate. During the 5-month period with resident participation, 555 trauma patients were admitted. In the identical time period without residents, 516 trauma patients were admitted. During the period without housestaff, patients were older and more severely injured. Mechanism was not different during the two time periods. Mortality was not affected; however, time in the emergency department and hospital lengths of stay were significantly shorter with residents. Multiple regression confirmed these findings while controlling for age, mechanism, and Injury Severity Score. Although resident participation in trauma care at a Level I trauma center does not affect outcome, it does significantly improve the efficiency of trauma care delivery.

Needs Assessment for Incoming PGY-1 Residents in Neurosurgical Residency.

Science.gov (United States)

Brandman, David M; Haji, Faizal A; Matte, Marie C; Clarke, David B

2015-01-01

Residents must develop a diverse range of skills in order to practice neurosurgery safely and effectively. The purpose of this study was to identify the foundational skills required for neurosurgical trainees as they transition from medical school to residency. Based on the CanMEDS competency framework, a web-based survey was distributed to all Canadian academic neurosurgical centers, targeting incoming and current PGY-1 neurosurgical residents as well as program directors. Using Likert scale and free-text responses, respondents rated the importance of various cognitive (e.g. management of raised intracranial pressure), technical (e.g. performing a lumbar puncture) and behavioral skills (e.g. obtaining informed consent) required for a PGY-1 neurosurgical resident. Of 52 individuals contacted, 38 responses were received. Of these, 10 were from program directors (71%), 11 from current PGY-1 residents (58%) and 17 from incoming PGY-1 residents (89%). Respondents emphasized operative skills such as proper sterile technique and patient positioning; clinical skills such as lesion localization and interpreting neuro-imaging; management skills for common scenarios such as raised intracranial pressure and status epilepticus; and technical skills such as lumbar puncture and external ventricular drain placement. Free text answers were concordant with the Likert scale results. We surveyed Canadian neurosurgical program directors and PGY-1 residents to identify areas perceived as foundational to neurosurgical residency education and training. This information is valuable for evaluating the appropriateness of a training program's goals and objectives, as well as for generating a national educational curriculum for incoming PGY-1 residents.

Assessment of the vaginal residence time of biomarkers of semen exposure.

Science.gov (United States)

Thurman, Andrea; Jacot, Terry; Melendez, Johan; Kimble, Thomas; Snead, Margaret; Jamshidi, Roxanne; Wheeless, Angie; Archer, David F; Doncel, Gustavo F; Mauck, Christine

2016-11-01

The primary objective of this pilot study is to determine and compare the residence time in the vagina of biomarkers of semen exposure for up to 15 days post exposure. The biomarkers are prostate-specific antigen (PSA), Y chromosome DNA, the sex determining region of the Y chromosome (SRY) and testis-specific protein Y-encoded 4 (TSPY4). The secondary objectives are to determine if biomarker concentrations differed between intercourse and inoculation groups, to establish whether the sampling frequency post exposure affected biomarker concentrations and decay profile and to determine if biomarker concentrations in vaginal swabs obtained by the participant at home were similar to swabs obtained by the nurse in the clinic. We randomized healthy women to unprotected intercourse (n=17) versus vaginal inoculation with the male partner's semen in the clinic (n=16). Women were then further randomized to have vaginal swabs obtained at either 7 or 4 time points after semen exposure, up to 15 days post exposure, either obtained at home by the participant or in the clinic by the research nurse. PSA and SRY were markers of recent semen exposure. TSPY4 was detectable in approximately 50% of participants at 15 days post exposure. Unprotected intercourse resulted in significantly higher concentrations of select biomarkers. Sampling frequency and home versus clinic sampling had no significant effect on biomarker concentrations. Objective biomarkers of recent or distant semen exposure may have great utility for verifying protocol compliance in a variety of clinical trials. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluating the impact of land use changes on the behaviour of shallow aquifers, by quantifying the groundwater mean residence times distribution

Science.gov (United States)

Vincent, Aude; Gillon, Marina; Marc, Vincent; Cognard-Plancq, Anne-Laure; Baillieux, Antoine; Babic, Milanka; Simler, Roland

2017-04-01

Residence time is one of the key factors of the groundwater resource management. The Crau aquifer (Mediterranean area, south of France) is a major resource for drinking water supply, threatened by climate change, changes in irrigation patterns, and urban expansion. Water residence time in the aquifer is expected to be highly dependent on these changes. We propose to determinate it using an isotopic approach, associated to numerical modelling. The Crau aquifer is a palaeo-alluvial fan of the Durance river, made of alluviums lying on a Miocene substratum, and recharged by rainwater and gravity irrigation water, diverted from the Durance river. The irrigation water being more depleted in 18O than the rain water, the contribution of irrigation to the aquifer recharge can be quantified (up to 80 to 85% of the total recharge), but is variable in space and time. The modelling approach uses two models, a lumped one and a discretised one. They are based on daily recharge data (rainfall, drainage rates under irrigated crops calculated from the STICS crop model, Olioso et al., 2013), and on monthly water sampling conducted from February 2012 to November 2016 for δ18O content in rainwater, surface water and groundwater. The lumped approach was carried out at a monthly time step, using a binary mixing model, including two exponentially draining reservoirs in parallel. It leads to a satisfying simulation of the δ18O variations in the monitored wells, and gives mean residence times between 3 and 20 months depending on the wells locations. The discretised model is a combination of MODFLOW and MODPATH, through the free user interface MODELMUSE, on a daily time-step. The permeability map used is the one calibrated by Baillieux et al. (2015). Recharge is applied with an increasing spatial complexity, in three successive steps: - a homogeneous recharge, provided by the intermediate output of the lumped model, in order to compare the two models results; - a recharge discretised in

Annual State of Connecticut Obstetrics and Gynecology Resident Research Day.

Science.gov (United States)

Seagle, Brandon-Luke L; Ballard, Jennifer; Kakar, Freshta; Panarelli, Erin; Samuelson, Robert; Shahabi, Shohreh

2015-01-01

To increase opportunities for Obstetrics and Gynecology(Ob/Gyn) residents to present their research, an Annual State of Connecticut Ob/Gyn Resident Research Day (RRD) was created. At the first annual RRD, 33 residents, representing five of six Connecticut Ob/Gyn residency programs, presented 39 poster and eight oral presentations. RRD evaluators rated the overall symposium and the quality of resident oral and poster presentations as either "excellent" or "above average." Residency program directors reported that the symposium was "very helpful" for evidencing resident scholarship as required by the Accreditation Council for Graduate Medical Education (ACGME). Surveyed residents reported that the symposium promoted their research and was a valuable investment of their time. An annual specialty-specific, statewide RRD was created, experienced good participation, and was well evaluated. The annual, statewide Ob/Gyn RRD may serve as a model for development of other specialty-specific, statewide RRD events.

Results of the 2012-2013 Association of Residents in Radiation Oncology (ARRO) Job Search and Career Planning Survey of Graduating Residents in the United States

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Mattes, Malcolm D., E-mail: mdm9007@nyp.org [Department of Radiation Oncology, New York Methodist Hospital, Brooklyn, New York (United States); Kharofa, Jordan [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Zeidan, Youssef H. [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Tung, Kaity [Department of Radiation Oncology, New York Methodist Hospital, Brooklyn, New York (United States); Gondi, Vinai [Department of Radiation Oncology, University of Wisconsin Comprehensive Cancer Center, Madison, Wisconsin (United States); Department of Radiation Oncology, Central Dupage Hospital Cancer Center, Warrenville, Illinois (United States); Golden, Daniel W. [Department of Radiation Oncology, Pritzker School of Medicine, University of Chicago, Chicago, Illinois (United States)

2014-01-01

Purpose/Objective(s): To determine the timeline used by postgraduate year (PGY)-5 radiation oncology residents during the job application process and the factors most important to them when deciding on a first job. Methods and Materials: In 2012 and 2013, the Association of Residents in Radiation Oncology conducted a nationwide electronic survey of PGY-5 radiation oncology residents in the United States during the final 2 months of their training. Descriptive statistics are reported. In addition, subgroup analysis was performed. Results: Surveys were completed by 180 of 314 residents contacted. The median time to start networking for the purpose of employment was January PGY-4; to start contacting practices, complete and upload a curriculum vitae to a job search website, and use the American Society of Radiation Oncology Career Center was June PGY-4; to obtain letters of recommendation was July PGY-5; to start interviewing was August PGY-5; to finish interviewing was December PGY-5; and to accept a contract was January PGY-5. Those applying for a community position began interviewing at an earlier average time than did those applying for an academic position (P=.04). The most important factors to residents when they evaluated job offers included (in order from most to least important) a collegial environment, geographic location, emphasis on best patient care, quality of support staff and facility, and multidisciplinary approach to patient care. Factors that were rated significantly different between subgroups based on the type of position applied for included adequate mentoring, dedicated research time, access to clinical trials, amount of time it takes to become a partner, geographic location, size of group, starting salary, and amount of vacation and days off. Conclusions: The residents' perspective on the job application process over 2 years is documented to provide a resource for current and future residents and employers to use.

Results of the 2012-2013 Association of Residents in Radiation Oncology (ARRO) job search and career planning survey of graduating residents in the United States.

Science.gov (United States)

Mattes, Malcolm D; Kharofa, Jordan; Zeidan, Youssef H; Tung, Kaity; Gondi, Vinai; Golden, Daniel W

2014-01-01

To determine the timeline used by postgraduate year (PGY)-5 radiation oncology residents during the job application process and the factors most important to them when deciding on a first job. In 2012 and 2013, the Association of Residents in Radiation Oncology conducted a nationwide electronic survey of PGY-5 radiation oncology residents in the United States during the final 2 months of their training. Descriptive statistics are reported. In addition, subgroup analysis was performed. Surveys were completed by 180 of 314 residents contacted. The median time to start networking for the purpose of employment was January PGY-4; to start contacting practices, complete and upload a curriculum vitae to a job search website, and use the American Society of Radiation Oncology Career Center was June PGY-4; to obtain letters of recommendation was July PGY-5; to start interviewing was August PGY-5; to finish interviewing was December PGY-5; and to accept a contract was January PGY-5. Those applying for a community position began interviewing at an earlier average time than did those applying for an academic position (P=.04). The most important factors to residents when they evaluated job offers included (in order from most to least important) a collegial environment, geographic location, emphasis on best patient care, quality of support staff and facility, and multidisciplinary approach to patient care. Factors that were rated significantly different between subgroups based on the type of position applied for included adequate mentoring, dedicated research time, access to clinical trials, amount of time it takes to become a partner, geographic location, size of group, starting salary, and amount of vacation and days off. The residents' perspective on the job application process over 2 years is documented to provide a resource for current and future residents and employers to use. Copyright © 2014 Elsevier Inc. All rights reserved.

Results of the 2012-2013 Association of Residents in Radiation Oncology (ARRO) Job Search and Career Planning Survey of Graduating Residents in the United States

International Nuclear Information System (INIS)

Mattes, Malcolm D.; Kharofa, Jordan; Zeidan, Youssef H.; Tung, Kaity; Gondi, Vinai; Golden, Daniel W.

2014-01-01

Purpose/Objective(s): To determine the timeline used by postgraduate year (PGY)-5 radiation oncology residents during the job application process and the factors most important to them when deciding on a first job. Methods and Materials: In 2012 and 2013, the Association of Residents in Radiation Oncology conducted a nationwide electronic survey of PGY-5 radiation oncology residents in the United States during the final 2 months of their training. Descriptive statistics are reported. In addition, subgroup analysis was performed. Results: Surveys were completed by 180 of 314 residents contacted. The median time to start networking for the purpose of employment was January PGY-4; to start contacting practices, complete and upload a curriculum vitae to a job search website, and use the American Society of Radiation Oncology Career Center was June PGY-4; to obtain letters of recommendation was July PGY-5; to start interviewing was August PGY-5; to finish interviewing was December PGY-5; and to accept a contract was January PGY-5. Those applying for a community position began interviewing at an earlier average time than did those applying for an academic position (P=.04). The most important factors to residents when they evaluated job offers included (in order from most to least important) a collegial environment, geographic location, emphasis on best patient care, quality of support staff and facility, and multidisciplinary approach to patient care. Factors that were rated significantly different between subgroups based on the type of position applied for included adequate mentoring, dedicated research time, access to clinical trials, amount of time it takes to become a partner, geographic location, size of group, starting salary, and amount of vacation and days off. Conclusions: The residents' perspective on the job application process over 2 years is documented to provide a resource for current and future residents and employers to use

Using skype as an alternative for residency selection interviews.

Science.gov (United States)

Edje, Louito; Miller, Christine; Kiefer, Jacklyn; Oram, David

2013-09-01

Residency interviews can place significant time and financial burdens on applicants. To determine whether the use of Skype as a screening tool during interview season in a family medicine residency is cost-effective and time-efficient for the applicant and the residency program. We surveyed 2 groups of medical students during interviews for our family medicine program. Thirty-two students were interviewed via our face-to-face, traditional interview (TI) process, and 10 students, the second group, who did not meet the program's standard interview selection criteria for TI, underwent our Skype interview (SI) process. Using an unpaired t test, we found that the applicants' costs of an SI were significantly less than a TI, $566 (95% confidence interval [CI] $784-$349, P Skype may be a cost-effective and time-efficient screening tool for both the applicant and the program. Alternate uses of SI may include the time-sensitive, postmatch Supplemental Offer and Acceptance Program.

Test determination with tritium as a radioactive tracer of the residence time distribution in the stability pool for Cabrero sewage

International Nuclear Information System (INIS)

Diaz, Francisco; Duran, Oscar; Henriquez, Pedro; Vega, Pedro; Padilla, Liliana; Gonzalez, David; Garcia Agudo, Edmundo

2000-01-01

This work was prepared by the Chilean and International Atomic Energy Agencies and covers the hydrodynamic functioning of sewage stability pools using tracers. The plant selected in the city of Cabrero, 500 km. south of Santiago, and is a rectangular facultative pool with a surface area of 7100 m 2 and a maximum volume of 12,327 m2 that receives an average flow of 20 l/s, serving a population of 7000 individuals. The work aims to characterize the runoff from the flow that enters the pool, using a radioactive tracer test, where the incoming water is marked, and its out-coming passage is determined, to establish the residence time distribution. Tritium was selected in the form of tritiated water as a tracer that is precisely emptied into the water flow from the distribution ravine at the lake entrance. Samples are taken at the outflow to determine the concentration of tritium after distillation, simultaneously measuring the flow, to be analyzed in a liquid flicker counter. An average test time of 5.3 days was obtained and an analysis of the residence time distribution for the tracer shows that it leaves quickly and indicates bad flow distribution in the lake with a major short circuit and probable dead zones

Estimation of groundwater residence time and evaluation of geomorphological processes using cosmogenic and terrigenic radionuclides and isotopes of noble gases

International Nuclear Information System (INIS)

Mahara, Yasunori; Ohta, Tomoko; Igarashi, Toshifumi

2013-01-01

In this paper, the estimation of groundwater residence time and geomorphological changing processes are discussed by focusing on isotopes of noble gases and radionuclides with a long half-life as an environmental tracer. Noble gases and radionuclides are produced in the atmospheric air and terrestrial rocks by spallation and various muon reactions during cosmic rays irradiation. Groundwater dating and geomorphological changing are estimated from changes in the number of atoms of cosmogenic and terrigenic nuclides in groundwater and terrestrial rock. The main tools of groundwater dating are combination of the dissolved helium and tritium (half-life T 1/2 =12.3 y) for younger groundwater less than 60 years of residence time, and of the dissolved helium and 36 Cl (T 1/2 =3.01 x 10 5 y) for older groundwater over million years. On the other hand, the main tools on the geomorphological changes are the estimation of exposure time using cosmogenic radionuclides ( 10 Be(half-life T 1/2 =1.6 x 10 6 y), 14 C (T 1/2 =5730 y), 26 Al (T 1/2 =7.16 x 10 5 y) and 36 Cl) and cosmogenic stable noble gases ( 3 He and 21 Ne) produced in rock. (author)

How Useful are Orthopedic Surgery Residency Web Pages?

Science.gov (United States)

Oladeji, Lasun O; Yu, Jonathan C; Oladeji, Afolayan K; Ponce, Brent A

2015-01-01

Medical students interested in orthopedic surgery residency positions frequently use the Internet as a modality to gather information about individual residency programs. Students often invest a painstaking amount of time and effort in determining programs that they are interested in, and the Internet is central to this process. Numerous studies have concluded that program websites are a valuable resource for residency and fellowship applicants. The purpose of the present study was to provide an update on the web pages of academic orthopedic surgery departments in the United States and to rate their utility in providing information on quality of education, faculty and resident information, environment, and applicant information. We reviewed existing websites for the 156 departments or divisions of orthopedic surgery that are currently accredited for resident education by the Accreditation Council for Graduate Medical Education. Each website was assessed for quality of information regarding quality of education, faculty and resident information, environment, and applicant information. We noted that 152 of the 156 departments (97%) had functioning websites that could be accessed. There was high variability regarding the comprehensiveness of orthopedic residency websites. Most of the orthopedic websites provided information on conference, didactics, and resident rotations. Less than 50% of programs provided information on resident call schedules, resident or faculty research and publications, resident hometowns, or resident salary. There is a lack of consistency regarding the content presented on orthopedic residency websites. As the competition for orthopedic websites continues to increase, applicants flock to the Internet to learn more about orthopedic websites in greater number. A well-constructed website has the potential to increase the caliber of students applying to a said program. Copyright © 2015 Association of Program Directors in Surgery. Published by

Awareness and willingness among the residents in Johor Bahru City Council and Johor Bahru Tengah Municipal Council of Iskandar Malaysia-Im (Wpi@Sjer towards recycling

Directory of Open Access Journals (Sweden)

Mohd Halim Nora Farina

2018-01-01

Full Text Available Solid waste is increasingly becoming an important urban challenge as a result from population growth and also the development of economy and culture which has improved the standard of living and the lifestyle of the people. If left unchecked, solid waste could lead to severe environmental degradation. In order to reduce the environmental impact of waste disposal, recycling has been introduced. About twenty percent of our solid waste can be recyclable, rather than disposing it through landfills or incinerators. Residential area is the best place to practice recycling because most of the waste is generated there every day. This research focus on the awareness level and the recycling knowledge among the residents in Johor Bahru City council and Johor Bahru Tengah Municipal Council of Iskandar Malaysia. A total of 500 residents were surveyed and the questionnaires were focused on the waste management and also the recycling knowledge. The results discovered that more than 50% of the residents’ state that they practicing recycle and they also aware of the environmental and economic benefits from recycling. As a conclusion, the residents are prepared for recycling if the recycling amenities are available and easy to reach by them.

Canadian pharmacy practice residents' projects: publication rates and study characteristics.

Science.gov (United States)

Hung, Michelle; Duffett, Mark

2013-03-01

Research projects are a key component of pharmacy residents' education. Projects represent both a large investment of effort for each resident (up to 10 weeks over the residency year) and a large body of research (given that there are currently over 150 residency positions in Canada annually). Publication of results is a vital part of the dissemination of information gleaned from these projects. To determine the publication rate for research projects performed under the auspices of accredited English-language hospital pharmacy residency programs in Canada and to describe the study characteristics of residency projects performed in Ontario from 1999/2000 to 2008/2009. Lists of residents and project titles for the period of interest were obtained from residency coordinators. PubMed, CINAHL, the Canadian Journal of Hospital Pharmacy, and Google were searched for evidence of publication of each project identified, as an abstract or presentation at a meeting, a letter to the editor, or a full-text manuscript. The library holdings of the University of Toronto were reviewed to determine study characteristics of the Ontario residency projects. For the objective of this study relating to publication rate, 518 projects were included. The overall publication rate was 32.2% (60 [35.9%] as abstracts and 107 [64.1%] as full-text manuscripts). Publication in pharmacy-specific journals (66 [61.7%] of 107 full-text manuscripts) was more frequent than publication in non-pharmacy-specific journals. The publication rate of projects as full-text manuscripts remained stable over time. Of the 202 Ontario residency projects archived in the University of Toronto's library, most were cohort studies (83 [41.1%]), and the most common topic was efficacy and/or safety of a medication (46 [22.8%]). Most hospital pharmacy residents' projects were unpublished, and the publication rate of projects as full-text manuscripts has not increased over time. Most projects were observational studies

[The European Working Time Directive and surgical residents' expertise: no effect on the number of operations].

Science.gov (United States)

Guicherit, Onno R

2015-01-01

Residents' working hours in the Netherlands were first capped in the early 1990 s. In 2003, European legislation consolidated restrictions to a 48-hour week. No adverse effects were seen on the number of surgical operations performed either in the first or the second decade following these measures. Either the effect on surgical training is minimal, or the number of operations carried out during a residency is not a meaningful indicator of its quality. Personalized modular rotations in both university and teaching hospitals are needed for residents with sub-specializations. Training activities, in combination with more supervision, have to focus on a broader set of competencies beyond simply mastering surgical procedures.

Effect of mixture ratio, solids concentration and hydraulic retention time on the anaerobic digestion of the organic fraction of municipal solid waste.

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Fongsatitkul, Prayoon; Elefsiniotis, Panagiotis; Wareham, David G

2010-09-01

This paper describes how the degradation of the organic fraction of municipal solid waste (OFMSW) is affected through codigestion with varying amounts of return activated sludge (RAS). Solid waste that had its inorganic fraction selectively removed was mixed with RAS in ratios of 100% OFMSW, 50% OFMSW/50% RAS, and 25% OFMSW/75% RAS. The total solids (TS) concentration was held at 8% and three anaerobic digester systems treating the mixtures were held (for the first run) at a total hydraulic retention time (HRT) of 28 days. Increasing amounts of RAS did not however improve the mixture's digestability, as indicated by little change and/or a drop in the main performance indices [including percentage volatile solids (VS) removal and specific gas production]. The optimum ratio in this research therefore appeared to be 100% OFMSW with an associated 85.1 ± 0.6% VS removal and 0.72 ± 0.01 L total gas g(- 1) VS. In the second run, the effect of increasing percentage of TS (8, 12% and 15%) at a system HRT of 28 days was observed to yield no improvement in the main performance indices (i.e. percentage VS removal and specific gas production). Finally, during the third run, variations in the total system HRT were investigated at an 8% TS, again using 100% OFMSW. Of the HRTs explored (23, 28 and 33 days), the longest HRT yielded the best performance overall, particularly in terms of specific gas production (0.77 ± 0.01 L total gas g(-1) VS).

Time series analysis of pressure fluctuation in gas-solid fluidized beds

Directory of Open Access Journals (Sweden)

C. Alberto S. Felipe

2004-09-01

Full Text Available The purpose of the present work was to study the differentiation of states of typical fluidization (single bubble, multiple bubble and slugging in a gas-solid fluidized bed, using spectral analysis of pressure fluctuation time series. The effects of the method of measuring (differential and absolute pressure fluctuations and the axial position of the probes in the fluidization column on the identification of each of the regimes studied were evaluated. Fast Fourier Transform (FFT was the mathematic tool used to analysing the data of pressure fluctuations, which expresses the behavior of a time series in the frequency domain. Results indicated that the plenum chamber was a place for reliable measurement and that care should be taken in measurement in the dense phase. The method allowed fluid dynamic regimes to be differentiated by their dominant frequency characteristics.

Impact of Resident Surgeons on Procedure Length based on Common Pediatric Otolaryngology Cases

Science.gov (United States)

Puram, Sidharth V.; Kozin, Elliott D.; Sethi, Rosh; Alkire, Blake; Lee, Daniel J.; Gray, Stacey T.; Shrime, Mark G.; Cohen, Michael

2015-01-01

Background Surgical education remains an important mission of academic medical centers. Financial pressures, however, may favor improved operating room (OR) efficiency at the expense of surgical education. We aim to characterize resident impact on the duration of procedural time using common pediatric otolaryngologic cases which do not necessitate a surgical assistant and assess whether other factors modify the extent to which residents impact OR efficiency. Study Design We retrospectively reviewed resident and attending surgeon total OR and procedural times for isolated tonsillectomy, adenoidectomy, tonsillectomy with adenoidectomy (T&A) and bilateral myringotomy with tube insertion between 2009 and 2013. We included cases supervised or performed by one of four teaching surgeons in children with ASA otolaryngology procedures. While residents may increase operative times, addressing other system-wide issues may decrease impact of time needed for education and added efficiencies of resident participation may exist throughout the perioperative period. Our model is applicable to surgical education across specialties. Level of Evidence 4 PMID:25251257

The case study of management of solid wastes in a petroleum industry; O estudo de caso do gerenciamento de residuos solidos em uma refinaria de petroleo

Energy Technology Data Exchange (ETDEWEB)

Araujo, Lizabela Souza de [Universidade Federal, Rio de Janeiro, RJ (Brazil). Escola de Quimica]. E-mail: lizabela@eq.ufrj.br; Nicolaiewsky, Elioni [Universidade Federal, Rio de Janeiro, RJ (Brazil). Escola de Quimica. Dept. de Engenharia Quimica]. E-mail: elioni@eq.ufrj.br; Freire, Denize D.C. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Escola de Quimica. Dept. de Engenharia Bioquimica]. E-mail: denize@eq.ufrj.br

2003-07-01

Crude oil refining is an industrial activity known as very pollutant, as all other activities of the petroleum industry, regarding either the volume or the concentration of the resides involved, thus generating emissions, effluents and solid wastes. The aim of the present work is to study solid waste management of a certain petroleum refinery, located in Rio de Janeiro. On the solid wastes management of that refinery, the following aspects were considered: origin and period of generation, conditioning, storage, transportation, treatment and final disposal. After listing all the resides and through analysis of the industrial wastes (norms, terms, inventory), the industrial process and office routines were then analyzed. The solid wastes were divided in two categories: industrial and administrative wastes. As far as destination is concerned, resides classified as Class I are either co-processed or incinerated, while Class II and Class III wastes, when not recycled, are sent to industrial or sanitary landfill. Finally, after analyzing the wastes management of the refinery, it has been proposed a plan of achievements in order to enhance the environmental goal of the refinery. (author)

Conversations with Holocaust survivor residents.

Science.gov (United States)

Hirst, Sandra P; LeNavenec, Carole Lynne; Aldiabat, Khaldoun

2011-03-01

Traumatic events in one's younger years can have an impact on how an individual copes with later life. One traumatic experience for Jewish individuals was the Holocaust. Some of these people are moving into long-term care facilities. It was within this context that the research question emerged: What are Holocaust survivor residents' perceptions of a life lived as they move into a long-term care facility? For this qualitative study, Holocaust survivors were individually interviewed. Findings emphasize that nursing care needs to ensure that Holocaust survivor residents participate in activities, receive timely health care, and receive recognition of their life experiences. Copyright 2011, SLACK Incorporated.

Neuroanatomy Education: The Impact on Perceptions, Attitudes, and Knowledge of an Intensive Course on General Practice Residents

Science.gov (United States)

Arantes, Mavilde; Barbosa, Joselina Maria; Ferreira, Maria Amélia

2017-01-01

General practitioners are responsible for the management of an increasing number of patients with neurological illness, and thus a solid education in neurosciences is a necessary component of their training. This study examines the effects of an intensive clinical neuroanatomy course on twenty general practice residents' perceptions, attitudes,…

Assessing work-related musculoskeletal symptoms among otolaryngology residents.

Science.gov (United States)

Wong, Kevin; Grundfast, Kenneth M; Levi, Jessica R

Previous studies have suggested that musculoskeletal symptoms are common among practicing otolaryngologists. Early training can be the ideal time to foster knowledge of ergonomics and develop safe work habits, however, little data exists regarding musculoskeletal symptoms in residents. The purpose of this study was to identify and characterize musculoskeletal symptoms in a preliminary sample of otolaryngology residents. A cross-sectional survey incorporating the Nordic Musculoskeletal Questionnaire was sent to 30 Otolaryngology-Head and Neck Surgery residencies to examine musculoskeletal symptoms among residents. A two-sample test of proportions was performed to compare symptoms between male and female residents. In total, 141 respondents (response rate=34.7%) completed the survey. Fifty-five percent of survey respondents were male and 45% were female. Musculoskeletal symptoms were most frequently reported in the neck (82.3%), followed by the lower back (56%), upper back (40.4%), and shoulders (40.4%). The most common symptoms were stiffness in the neck (71.6%), pain in the neck (61.7%), and pain in the lower back (48.2%). In total, 6.4% of residents missed work and 16.3% of residents stopped during an operation at some point due to their symptoms. Most residents (88.3%) believed their musculoskeletal symptoms were attributed to their surgical training. Female residents were significantly more likely to experience neck (p<0.0001) and wrist/hand (p=0.019) discomfort compared to male residents. Musculoskeletal symptoms were common among residents, approaching rates similar to those previously identified in practicing otolaryngologists. Increased emphasis on surgical ergonomics is warranted to improve workplace safety and prevent future injury. Copyright © 2017. Published by Elsevier Inc.

Selection criteria of residents for residency programs in Kuwait.

Science.gov (United States)

Marwan, Yousef; Ayed, Adel

2013-01-19

In Kuwait, 21 residency training programs were offered in the year 2011; however, no data is available regarding the criteria of selecting residents for these programs. This study aims to provide information about the importance of these criteria. A self-administered questionnaire was used to collect data from members (e.g. chairmen, directors, assistants …etc.) of residency programs in Kuwait. A total of 108 members were invited to participate. They were asked to rate the importance level (scale from 1 to 5) of criteria that may affect the acceptance of an applicant to their residency programs. Average scores were calculated for each criterion. Of the 108 members invited to participate, only 12 (11.1%) declined to participate. Interview performance was ranked as the most important criteria for selecting residents (average score: 4.63/5.00), followed by grade point average (average score: 3.78/5.00) and honors during medical school (average score: 3.67/5.00). On the other hand, receiving disciplinary action during medical school and failure in a required clerkship were considered as the most concerning among other criteria used to reject applicants (average scores: 3.83/5.00 and 3.54/5.00 respectively). Minor differences regarding the importance level of each criterion were noted across different programs. This study provided general information about the criteria that are used to accept/reject applicants to residency programs in Kuwait. Future studies should be conducted to investigate each criterion individually, and to assess if these criteria are related to residents' success during their training.

Drug-target residence time--a case for G protein-coupled receptors.

Science.gov (United States)

Guo, Dong; Hillger, Julia M; IJzerman, Adriaan P; Heitman, Laura H

2014-07-01

A vast number of marketed drugs act on G protein-coupled receptors (GPCRs), the most successful category of drug targets to date. These drugs usually possess high target affinity and selectivity, and such combined features have been the driving force in the early phases of drug discovery. However, attrition has also been high. Many investigational new drugs eventually fail in clinical trials due to a demonstrated lack of efficacy. A retrospective assessment of successfully launched drugs revealed that their beneficial effects in patients may be attributed to their long drug-target residence times (RTs). Likewise, for some other GPCR drugs short RT could be beneficial to reduce the potential for on-target side effects. Hence, the compounds' kinetics behavior might in fact be the guiding principle to obtain a desired and durable effect in vivo. We therefore propose that drug-target RT should be taken into account as an additional parameter in the lead selection and optimization process. This should ultimately lead to an increased number of candidate drugs moving to the preclinical development phase and on to the market. This review contains examples of the kinetics behavior of GPCR ligands with improved in vivo efficacy and summarizes methods for assessing drug-target RT. © 2014 Wiley Periodicals, Inc.

Factors influencing resident's decision to reside in gated and guarded community

Science.gov (United States)

Shamsudin, Zarina; Shamsudin, Shafiza; Zainal, Rozlin

2017-10-01

Gated communities are residential areas developed with restricted access with strictly controlled entrances and surrounded by a close perimeter of wall or fences. Developers, conscious of the need to fulfill the requirement of living in modern and sophisticated lifestyle and gated properties become the trend and mushroomed over the past decade. Nowadays, it is obvious that gated and guarded communities become almost a dominant feature of Malaysia housing development projects. The focus of this paper is to identify the factors contribute resident's decision to reside in gated and guarded community and to study social interaction among gated communities' residents. 150 questionnaires were distributed to the residents of selected gated and guarded community area in order to achieve the objectives and analyzed by using Statistical Package for Social Science (SPSS) and descriptive analysis. The result was tabulated and presented in charts and graphs for a clear and better understanding. The five main factors contribute to resident decision to reside in gated communities were identified and ranked; there are privacy, security, location, lifestyle and prestige. Besides, the residents are feeling neutral towards the facilities and services provided in their gated and guarded residential area. A comprehensive improvement towards the facilities and services is needed to reach higher satisfaction from the residents.

Quantification of VX Nerve Agent in Various Food Matrices by Solid-Phase Extraction Ultra-Performance Liquid ChromatographyTime-of-Flight Mass Spectrometry

Science.gov (United States)

2016-04-01

QUANTIFICATION OF VX NERVE AGENT IN VARIOUS FOOD MATRICES BY SOLID - PHASE EXTRACTION ULTRA-PERFORMANCE...TITLE AND SUBTITLE Quantification of VX Nerve Agent in Various Food Matrices by Solid - Phase Extraction Ultra-Performance Liquid Chromatography...QUANTIFICATION OF VX NERVE AGENT IN VARIOUS FOOD MATRICES BY SOLID - PHASE EXTRACTION ULTRA-PERFORMANCE LIQUID CHROMATOGRAPHY–TIME-OF-FLIGHT MASS

Modeling of pretreatment and acidogenic fermentation of the organic fraction of municipal solid wastes

Energy Technology Data Exchange (ETDEWEB)

Beccari, M; Longo, G; Majone, M; Rolle, E; Scarinci, A [Rome ' ' La Sapienza' ' Univ. (Italy). Dept. of Chemistry

1993-01-01

The organic fraction of municipal solid waste represents a potential feedstock to be treated through biorefining. However, the process feasibility strongly depends on the effectiveness of a chemical pretreatment. Consequently, experimentation aimed at choosing the optimal type of reagent (alkali or acids) and optimal operating conditions was carried out. The best results were obtained using NaOH at room temperature. Solubilization data are in good agreement with a kinetics based on two competing reactions. Simulation of the overall process (pretreatment and acidogenic fermentation) taking place in two CFSTR reactors shows that an optimum ratio exists between the hydraulic residence times of the two stages of the process. (author)

General surgery training without laparoscopic surgery fellows: the impact on residents and patients.

Science.gov (United States)

Linn, John G; Hungness, Eric S; Clark, Sara; Nagle, Alexander P; Wang, Edward; Soper, Nathaniel J

2011-10-01

To evaluate resident case volume after discontinuation of a laparoscopic surgery fellowship, and to examine disparities in patient care over the same time period. Resident case logs were compared for a 2-year period before and 1 year after discontinuing the fellowship, using a 2-sample t test. Databases for bariatric and esophageal surgery were reviewed to compare operative time, length of stay (LOS), and complication rate by resident or fellow over the same time period using a 2-sample t test. Increases were seen in senior resident advanced laparoscopic (Mean Fellow Year = 21 operations vs Non Fellow Year = 61, P surgery. Operative time for complex operations may increase in the absence of a fellow. Other patient outcomes are not affected by this change. Copyright © 2011 Mosby, Inc. All rights reserved.

The clinician-educator track: training internal medicine residents as clinician-educators.

Science.gov (United States)

Smith, C Christopher; McCormick, Ian; Huang, Grace C