Sample records for working time patterns

  1. The French 35-hour workweek: a wide-ranging social change.

    PubMed

    Prunier-Poulmaire, S; Gadbois, C

    2001-12-01

    The reduction of the legal working week to 35 hours in France has generated wide-ranging social change. We examine the resulting changes in working-time patterns as well as their repercussions on the use of the time gained and on the quality of life and health. To compensate the reduction in the length of the working week, companies have modified the working-time patterns, by extending operation time (shiftwork, atypical schedules) and by matching the on-site workforce to production requirements (flexible working hours). They have sought to make more efficient use of working time: job intensification or job compression. The effects on the off-the-job life and health are linked to the shiftwork and atypical schedules designed to increase the company's operating time, and adjustments to the company's need for flexibilization impose working time/free time patterns that are at odds with biological rhythms and social life patterns. Changes to working-time patterns have unexpected consequences for work organization: heightened difficulties for the individual and the crew. These changes may generate a range of health problems related to overwork and stress. The way some companies have adapted may call into question the usefulness of work done by employees, thus damaging their social identity and mental well-being.

  2. Alternative Work Patterns: Implications for Worklife Education and Training. Worker Education and Training Policies Project.

    ERIC Educational Resources Information Center

    Shore, Jane

    This monograph explores the major categories of alternative work patterns, e.g., flexitime, permanent part-time employment, job sharing, the compressed work week, and reduced work time. Advantages and disadvantages of each type are discussed, and new insight is offered into an unexplored dimension of the major types of alternative work patterns:…

  3. Sitting Time, Physical Activity and Sleep by Work Type and Pattern-The Australian Longitudinal Study on Women's Health.

    PubMed

    Clark, Bronwyn K; Kolbe-Alexander, Tracy L; Duncan, Mitch J; Brown, Wendy

    2017-03-10

    Data from the Australian Longitudinal Study on Women's Health were used to examine how work was associated with time spent sleeping, sitting and in physical activity (PA), in working women. Young (31-36 years; 2009) and mid-aged (59-64 years; 2010) women reported sleep (categorised as shorter ≤6 h/day and longer ≥8 h/day) and sitting time (work, transport, television, non-work computer, and other; summed for total sitting time) on the most recent work and non-work day; and moderate and vigorous PA (categorised as meeting/not meeting guidelines) in the previous week. Participants reported occupation (manager/professional; clerical/sales; trades/transport/labourer), work hours (part-time; full-time) and work pattern (shift/night; not shift/night). The odds of shorter sleep on work days was higher in both cohorts for women who worked shift or night hours. Longer sitting time on work days, made up primarily of sitting for work, was found for managers/professionals, clerical/sales and full-time workers. In the young cohort, clerical/sales workers and in the mid-aged cohort, full-time workers were less likely to meet PA guidelines. These results suggest multiple behaviour interventions tailored to work patterns and occupational category may be useful to improve the sleep, sitting and activity of working women.

  4. Working patterns and vitamin D status in mid-life: a cross-sectional study of the 1958 British birth cohort.

    PubMed

    Ward, Maria; Berry, Diane J; Power, Chris; Hyppönen, Elina

    2011-12-01

    To assess the association between working patterns and vitamin D status in men and women and to determine the potential influence of related lifestyle and socioeconomic factors. The authors used data from the 1958 British birth cohort (aged 45 years) and 6154 participants, who were in full-time work, were included in current analyses. Vitamin D status was measured by circulating concentrations of 25-hydroxyvitamin D (25(OH)D). Information on working patterns and lifestyle factors was obtained using a structured questionnaire administered at 45 years. Manual social class was strongly associated with vitamin D-related lifestyle factors, with those in manual classes not only spending more time outdoors, but also spending more time watching TV/using PC, consuming less supplements and oily fish. Associations between working patterns and vitamin D-related lifestyles were less clear: night work was not strongly associated with lifestyles in either gender, while working hours were associated with time spent outside, PC/TV leisure time and use of supplements in men but not in women. In men, working patterns were not associated with lower 25(OH)D concentrations. In women, 25(OH)D concentrations were 8% lower (95% CI 15% to 2%) in night workers compared with others, while women working less than 35 h/week had 5% higher concentrations of 25(OH)D (95% CI 1% to 8%) compared with those working 35-40 h/week after adjustment for season, social class and body mass index (BMI). Women working nights and longer hours may be vulnerable to deficits in vitamin D status and associated health hazards.

  5. The impact of shift work on eating patterns and self-care strategies utilised by experienced and inexperienced nurses.

    PubMed

    Gifkins, Jane; Johnston, Amy; Loudoun, Rebecca

    2018-05-08

    For nurses, shift work is a necessity, required to provide 24-h continuous care for patients. Research posits that fatigue amongst shift-working nurses is associated with inadequate and poorly timed sleep and also strongly influenced by the timing, quality and quantity of food consumed. The aim of this investigation was to examine differences and similarities in the food choices and eating patterns of nurses exposed to different lengths of time in shift work, as a means of understanding how nurses can adapt their eating patterns to better manage fatigue and sleep loss. Qualitative methodology was utilised to study and capture in-depth information about nurses' daily working lives. A case study approach allowed for the investigation of nurses with limited and extensive experience of shift work. Increased food craving, caffeine consumption and snacking behaviours during night shifts were described by both groups of nurses, as was the inability to drink enough fluids at work. Meal skipping at work, associated with high workload, was detailed more by experienced nurses. Experienced nurses described shopping and preparing home cooked meals in advance to manage food intake and associated fatigue, contrasting with patterns from inexperienced nurses. Experienced nurses recounted drinking alcohol as a way to rest and recover from shift work, unlike their less inexperienced colleagues. These findings indicate organisational and work place issues such as shift work and rostering influence the food choices and eating patterns of shift-working nurses. Experienced nurses, however, draw on a greater range of strategies around diet and eating patterns to minimise these impacts.

  6. Work routines moderate the association between eveningness and poor psychological well-being

    PubMed Central

    de Souza, Camila Morelatto; Hidalgo, Maria Paz Loayza

    2018-01-01

    Well-being is a useful screening method for the detection of mood disorders. Evidence associating psychological well-being with sleep-wake patterns exists, as well as associations with sleep-wake patterns, work-related parameters, and perceived self-efficacy. Despite the growing research regarding the relationship between these factors and mental health, there are few studies that analyze them together. OBJECTIVE: To investigate if the association between sleep-wake patterns and psychological well-being is mediated or moderated by perceived self-efficacy, work flexibility and work routines. MATERIAL AND METHODS: This cohort study was performed in southern Brazil. A sample of 987 individuals was analyzed (66.9% women; mean age = 43.9 years). Work routines parameters and work schedule flexibility were evaluated, most participants were farmers (46%) and most worked 7 days a week (69.1%). Munich Chronotype Questionnaire (MCTQ) was administered for evaluation of sleep-wake patterns, General Self-Efficacy Scale (GSE) for assessment the participants’ beliefs about how they coped with daily hassles, and World Health Organization Five-item Well-being Index (WHO-5) for evaluation of psychological well-being levels. Moderation and mediation models were tested. RESULTS: The moderation model showed influences of work end time on the relationship between sleep onset time and psychological well-being (R2 = 0.147; F = 24.16; p<0.001). The final regression model showed an association of psychological well-being with sex (Beta = -0.086; p = 0.004), sleep onset time (Beta = -0.086; p = 0.006), and self-efficacy (Beta = 0.316; p<0.001); the work end time showed association in the interaction with sleep onset time (Beta = -0.075; p = 0.016). CONCLUSION: The findings support the direct association of psychological well-being with sleep-wake patterns and self-efficacy, and show an interaction between work routines and sleep-wake patterns. Our results draw attention to the importance of the interplay between individual and social rhythms in relation to psychological well-being. PMID:29624593

  7. Changing Schedules of Work: Patterns and Implications. Final Report.

    ERIC Educational Resources Information Center

    Glickman, Albert S.; Brown, Zenia H.

    The past few years have been highlighted by management experiments with variants of a 4-day week (particularly in the U.S.) and flexible working time schedules (particularly in Europe). These are illustrations of the changing patterns of work and free time that have begun to assume the status of a new technology, and which are the objects of study…

  8. Mining Recent Temporal Patterns for Event Detection in Multivariate Time Series Data

    PubMed Central

    Batal, Iyad; Fradkin, Dmitriy; Harrison, James; Moerchen, Fabian; Hauskrecht, Milos

    2015-01-01

    Improving the performance of classifiers using pattern mining techniques has been an active topic of data mining research. In this work we introduce the recent temporal pattern mining framework for finding predictive patterns for monitoring and event detection problems in complex multivariate time series data. This framework first converts time series into time-interval sequences of temporal abstractions. It then constructs more complex temporal patterns backwards in time using temporal operators. We apply our framework to health care data of 13,558 diabetic patients and show its benefits by efficiently finding useful patterns for detecting and diagnosing adverse medical conditions that are associated with diabetes. PMID:25937993

  9. Differences between work and leisure in temporal patterns of objectively measured physical activity among blue-collar workers.

    PubMed

    Hallman, David M; Mathiassen, Svend Erik; Gupta, Nidhi; Korshøj, Mette; Holtermann, Andreas

    2015-09-28

    Leisure time physical activity (LTPA) is generally associated with favorable cardiovascular health outcomes, while occupational physical activity (OPA) shows less clear, or even opposite, cardiovascular effects. This apparent paradox is not sufficiently understood, but differences in temporal patterns of OPA and LTPA have been suggested as one explanation. Our aim was to investigate the extent to which work and leisure (non-occupational time) differ in temporal activity patterns among blue-collar workers, and to assess the modification of these patterns by age and gender. This study was conducted on a cross-sectional sample of male (n = 108) and female (n = 83) blue-collar workers, aged between 21 and 65 years. Physical activity and sedentary behavior were assessed using accelerometers (Actigraph GT3X+) worn on the thigh and trunk for four consecutive days. Temporal patterns of OPA and LTPA were retrieved using Exposure Variation Analysis (EVA), and expressed in terms of percentage of work and leisure time spent in uninterrupted periods of different durations (<1 min, 1-5 min, 5-10 min, 10-30 min, 30-60 min and > 60 min) of sitting, standing, and walking. Repeated measures ANOVA and linear regression analyses were used to test a) possible differences between OPA and LTPA in selected EVA derivatives, and b) the modification of these differences by age and gender. OPA showed a larger percentage time walking in brief (<5 min) periods [mean (SD): 33.4 % (12.2)], and less time in prolonged (>30 min) sitting [7.0 % (9.3)] than LTPA [walking 15.4 % (5.0); sitting 31.9 % (15.3)], even after adjustment for the difference between work and leisure in total time spent in each activity type. These marked differences in the temporal pattern of OPA and LTPA were modified by gender, but not age. We found that the temporal patterns of OPA and LTPA among blue-collar workers were markedly different even after adjustment for total physical activity time, and that this difference was modified by gender. We recommend using EVA derivatives in future studies striving to disentangle the apparent paradoxical cardiovascular effect of physical activity at work and during leisure.

  10. Children's Time Use: Labor Divisions and Schooling in Indonesia

    ERIC Educational Resources Information Center

    Hsin, Amy

    2007-01-01

    Data from the Worker and Iron Status Evaluation are used to examine gendered patterns in children's time in market and nonmarket work, schooling, and leisure in Indonesia (N = 2,929). Boys spend more time in market work; girls spend more time in nonmarket work. Work responsibilities increase with age as well as gender differentials in children's…

  11. Sitting Time, Physical Activity and Sleep by Work Type and Pattern—The Australian Longitudinal Study on Women’s Health

    PubMed Central

    Clark, Bronwyn K.; Kolbe-Alexander, Tracy L.; Duncan, Mitch J.; Brown, Wendy

    2017-01-01

    Data from the Australian Longitudinal Study on Women’s Health were used to examine how work was associated with time spent sleeping, sitting and in physical activity (PA), in working women. Young (31–36 years; 2009) and mid-aged (59–64 years; 2010) women reported sleep (categorised as shorter ≤6 h/day and longer ≥8 h/day) and sitting time (work, transport, television, non-work computer, and other; summed for total sitting time) on the most recent work and non-work day; and moderate and vigorous PA (categorised as meeting/not meeting guidelines) in the previous week. Participants reported occupation (manager/professional; clerical/sales; trades/transport/labourer), work hours (part-time; full-time) and work pattern (shift/night; not shift/night). The odds of shorter sleep on work days was higher in both cohorts for women who worked shift or night hours. Longer sitting time on work days, made up primarily of sitting for work, was found for managers/professionals, clerical/sales and full-time workers. In the young cohort, clerical/sales workers and in the mid-aged cohort, full-time workers were less likely to meet PA guidelines. These results suggest multiple behaviour interventions tailored to work patterns and occupational category may be useful to improve the sleep, sitting and activity of working women. PMID:28287446

  12. The influence of work patterns on indicators of cardiometabolic risk in female hospital employees.

    PubMed

    Kirk, Megan; VanDenKerkhof, Elizabeth; Janssen, Ian; Tranmer, Joan

    2015-05-01

    This study explored the associations between work patterns and indicators of cardiometabolic risk in female hospital employees. Aspects of work environments potentially influence the health of employees; however, we have a poor understanding of how different hospital work patterns contribute to cardiovascular risk in female employees. We conducted a cross-sectional study of 466 female employees from 2 hospitals in Ontario. Data were collected through self-report, physical examination, and use of hospital administrative work data. In the adjusted analyses, full-time work status, extended shift length, and working 35 or more paid overtime hours per year were significantly associated with metabolic syndrome. Different work patterns increase cardiometabolic risk in female employees, suggesting a need to better monitor the health of the workforce and implement healthy workplace policy.

  13. Job Sharing. A New Pattern for Quality of Work and Life.

    ERIC Educational Resources Information Center

    Meier, Gretl S.

    Job sharing, a new option in permanent part-time employment, is attracting national attention as a viable alternative to more traditional patterns of work. Job sharing is defined as an arrangement whereby two employees hold a position together, whether they are as a team jointly responsible for the whole or separately for each half, dividing time,…

  14. Searching for serial refreshing in working memory: Using response times to track the content of the focus of attention over time.

    PubMed

    Vergauwe, Evie; Hardman, Kyle O; Rouder, Jeffrey N; Roemer, Emily; McAllaster, Sara; Cowan, Nelson

    2016-12-01

    One popular idea is that, to support the maintenance of a set of elements over brief periods of time, the focus of attention rotates among the different elements, thereby serially refreshing the content of working memory (WM). In the research reported here, probe letters were presented between to-be-remembered letters, and response times to these probes were used to infer the status of the different items in WM. If the focus of attention cycles from one item to the next, its content should be different at different points in time, and this should be reflected in a change in the response time patterns over time. Across a set of four experiments, we demonstrated a striking pattern of invariance in the response time patterns over time, suggesting either that the content of the focus of attention did not change over time or that response times cannot be used to infer the content of the focus of attention. We discuss how this pattern constrains models of WM, attention, and human information processing.

  15. Sex work in Tallinn, Estonia: the sociospatial penetration of sex work into society.

    PubMed

    Aral, S O; St Lawrence, J S; Uusküla, A

    2006-10-01

    It is important to describe and understand the underlying patterns and dynamics that govern sex work in societies undergoing rapid political and social changes, its heterogeneity across populations, and its evolution through time in order to inform future research, sound policy formation, and programme delivery. To describe the socioeconomic and cultural determinants, organisational structure, distinct categories, and spatial patterning of sex work in Tallinn, Estonia, and identify recent temporal changes in sex work patterns. In-depth interviews with key informants; naturalistic observations of sex work and drug use venues, geo-mapping of sex work sites, review of media, public policy, and commissioned reports, and analyses of existing data. Sex work takes place in a hierarchy of locations in Tallinn ranging from elite brothels and "love flats" to truck stops. These sites vary in terms of their public health importance and social organisation. There are full time, part time, and intermittent male and female sex workers. Among others, the taxi driver, madam and the bartender are central roles in the organisation of sex work in Tallinn. Cell phone and internet technology enable sex work to be highly dispersed and spatially mobile. Future research and programmatic service delivery or outreach efforts should respond to the changing profile of sex work in Tallinn and its implications for STD/HIV epidemiology.

  16. Patterns of Success and Failure in the Transition from School to Work in Australia. Research Report.

    ERIC Educational Resources Information Center

    Lamb, Stephen; McKenzie, Phillip

    Patterns of success and failure in the transition from school to work in Australia in the 1980s-1990s were examined by analyzing data from the Australian Youth Survey. Of those studied, 20% found full-time jobs upon leaving school and remained in full-time employment for the next 7 years, 13% obtained apprenticeships or traineeships leading to…

  17. No time for the gym? Housework and other non-labor market time use patterns are associated with meeting physical activity recommendations among adults in full-time, sedentary jobs.

    PubMed

    Smith, Lindsey P; Ng, Shu Wen; Popkin, Barry M

    2014-11-01

    Physical activity and inactivity have distinct cardio-metabolic consequences, suggesting that combinations of activities can impact health above and beyond the effects of a single activity. However, little work has examined patterns of non-labor market time activity in the US population, particularly among full-time employees in sedentary occupations, who are at increased risk of adverse health consequences associated with a sedentary lifestyle. Identification of these patterns, and how they are related to total physical activity levels, is important for developing effective, attainable physical activity recommendations among sedentary employees, who typically have less time available for exercise. This is especially the case for low-income employees who face the highest time and financial barriers to achieving physical activity goals. This study uses cluster analysis to examine patterns of non-labor market time use among full-time (≥40 h/week) employed adults in sedentary occupations (<3 MET-h) on working days in the American Time Use Study. We then examine whether these patterns are associated with higher likelihood of meeting physical activity recommendations and higher overall physical activity (MET-h). We find that non-labor market time use patterns include those characterized by screen activities, housework, caregiving, sedentary leisure, and exercise. For both genders, the screen pattern was the most common and increased from 2003 to 2012, while the exercise pattern was infrequent and consistent across time. Screen, sedentary leisure, and community patterns were associated with lower likelihoods of meeting physical activity recommendations, suggesting that interventions targeting screen time may miss opportunities to improve physical activity among similarly sedentary groups. Alternately, non-labor market time use patterns characterized by housework and caregiving represented feasible avenues for increasing overall physical activity levels, especially for those with low financial and time resources. Consideration of non-labor market time use patterns may improve strategies to increase physical activity and decrease inactivity among full-time employed adults in sedentary jobs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Flex-Time. A Catalyst Occasional Paper.

    ERIC Educational Resources Information Center

    Catalyst, New York, NY.

    Contains history, case studies, and discussion of the use and benefits of flex-time employment, a pattern of working hours in which individual employees begin and end their work day at times of their choice, within certain limits, as long as they work a prescribed number of hours. The paper addresses the following topics: (1) What is flex-time,…

  19. Workdays, Workhours, and Work Schedules: Evidence for the United States and Germany.

    ERIC Educational Resources Information Center

    Hamermesh, Daniel S.

    This book studies work in the United States and Germany from two new viewpoints: (1) the division of work time into hours per day and days per week (as opposed to the standard analysis of weekly hours of work); and (2) the patterns of the particular times of the day and week when people are working, a focus on instantaneous time use. Information…

  20. TRACING THE TIMING OF “CAREER” ACQUISITION IN A CONTEMPORARY YOUTH COHORT*

    PubMed Central

    Mortimer, Jeylan T.; Vuolo, Mike; Staff, Jeremy; Wakefield, Sara; Xie, Wanling

    2008-01-01

    Contemporary youth typically experience considerable floundering and uncertainty in their transition from school to work. This paper examines patterns of schooling and working during adolescence and the transition to adulthood that hasten or delay an important subjective marker of transition to adulthood: acquiring a job that is recognized as a “career.” We use Youth Development Study data, obtained from a prospective longitudinal study of 9th graders. Estimation of discrete-time logit models shows that adolescent work patterns during high school, as well as the cumulative investments they make in work and schooling in the years following, significantly influence this milestone. Time-varying predictors, including job characteristics and parenthood, also affect the process of movement into “careers”. PMID:18542713

  1. Portraits of Principal Practice: Time Allocation and School Principal Work

    ERIC Educational Resources Information Center

    Sebastian, James; Camburn, Eric M.; Spillane, James P.

    2018-01-01

    Purpose: The purpose of this study was to examine how school principals in urban settings distributed their time working on critical school functions. We also examined who principals worked with and how their time allocation patterns varied by school contextual characteristics. Research Method/Approach: The study was conducted in an urban school…

  2. Sex work in Tallinn, Estonia: the sociospatial penetration of sex work into society

    PubMed Central

    Aral, S O; Lawrence, J S St; Uusküla, A

    2006-01-01

    Background It is important to describe and understand the underlying patterns and dynamics that govern sex work in societies undergoing rapid political and social changes, its heterogeneity across populations, and its evolution through time in order to inform future research, sound policy formation, and programme delivery. Objectives To describe the socioeconomic and cultural determinants, organisational structure, distinct categories, and spatial patterning of sex work in Tallinn, Estonia, and identify recent temporal changes in sex work patterns. Methods In‐depth interviews with key informants; naturalistic observations of sex work and drug use venues, geo‐mapping of sex work sites, review of media, public policy, and commissioned reports, and analyses of existing data. Results Sex work takes place in a hierarchy of locations in Tallinn ranging from elite brothels and “love flats” to truck stops. These sites vary in terms of their public health importance and social organisation. There are full time, part time, and intermittent male and female sex workers. Among others, the taxi driver, madam and the bartender are central roles in the organisation of sex work in Tallinn. Cell phone and internet technology enable sex work to be highly dispersed and spatially mobile. Conclusion Future research and programmatic service delivery or outreach efforts should respond to the changing profile of sex work in Tallinn and its implications for STD/HIV epidemiology. PMID:16807288

  3. Workers' compensation claims for musculoskeletal disorders and injuries of the upper extremity and knee among union carpenters in Washington State, 1989-2008.

    PubMed

    Lipscomb, Hester J; Schoenfisch, Ashley L; Cameron, Wilfrid; Kucera, Kristen L; Adams, Darrin; Silverstein, Barbara A

    2015-04-01

    Numerous aspects of construction place workers at risk of musculoskeletal disorders and injuries (MSDIs). Work organization and the nature of MSDIs create surveillance challenges. By linking union records with workers' compensation claims, we examined 20-year patterns of MSDIs involving the upper extremity (UE) and the knee among a large carpenter cohort. MSDIs were common and accounted for a disproportionate share of paid lost work time (PLT) claims; UE MSDIs were three times more common than those of the knee. Rates declined markedly over time and were most pronounced for MSDIs of the knee with PLT. Patterns of risk varied by extremity, as well as by age, gender, union tenure, and predominant work. Carpenters in drywall installation accounted for the greatest public health burden. A combination of factors likely account for the patterns observed over time and across worker characteristics. Drywall installers are an intervention priority. © 2015 Wiley Periodicals, Inc.

  4. Design, application and testing of the Work Observation Method by Activity Timing (WOMBAT) to measure clinicians' patterns of work and communication.

    PubMed

    Westbrook, Johanna I; Ampt, Amanda

    2009-04-01

    Evidence regarding how health information technologies influence clinicians' patterns of work and support efficient practices is limited. Traditional paper-based data collection methods are unable to capture clinical work complexity and communication patterns. The use of electronic data collection tools for such studies is emerging yet is rarely assessed for reliability or validity. Our aim was to design, apply and test an observational method which incorporated the use of an electronic data collection tool for work measurement studies which would allow efficient, accurate and reliable data collection, and capture greater degrees of work complexity than current approaches. We developed an observational method and software for personal digital assistants (PDAs) which captures multiple dimensions of clinicians' work tasks, namely what task, with whom, and with what; tasks conducted in parallel (multi-tasking); interruptions and task duration. During field-testing over 7 months across four hospital wards, fifty-two nurses were observed for 250 h. Inter-rater reliability was tested and validity was measured by (i) assessing whether observational data reflected known differences in clinical role work tasks and (ii) by comparing observational data with participants' estimates of their task time distribution. Observers took 15-20 h of training to master the method and data collection process. Only 1% of tasks observed did not match the classification developed and were classified as 'other'. Inter-rater reliability scores of observers were maintained at over 85%. The results discriminated between the work patterns of enrolled and registered nurses consistent with differences in their roles. Survey data (n=27) revealed consistent ratings of tasks by nurses, and their rankings of most to least time-consuming tasks were significantly correlated with those derived from the observational data. Over 40% of nurses' time was spent in direct care or professional communication, with 11.8% of time spent multi-tasking. Nurses were interrupted approximately every 49 min. One quarter of interruptions occurred while nurses were preparing or administering medications. This method efficiently produces reliable and valid data. The multi-dimensional nature of the data collected provides greater insights into patterns of clinicians' work and communication than has previously been possible using other methods.

  5. Characteristics of the transmission of autoregressive sub-patterns in financial time series

    NASA Astrophysics Data System (ADS)

    Gao, Xiangyun; An, Haizhong; Fang, Wei; Huang, Xuan; Li, Huajiao; Zhong, Weiqiong

    2014-09-01

    There are many types of autoregressive patterns in financial time series, and they form a transmission process. Here, we define autoregressive patterns quantitatively through an econometrical regression model. We present a computational algorithm that sets the autoregressive patterns as nodes and transmissions between patterns as edges, and then converts the transmission process of autoregressive patterns in a time series into a network. We utilised daily Shanghai (securities) composite index time series to study the transmission characteristics of autoregressive patterns. We found statistically significant evidence that the financial market is not random and that there are similar characteristics between parts and whole time series. A few types of autoregressive sub-patterns and transmission patterns drive the oscillations of the financial market. A clustering effect on fluctuations appears in the transmission process, and certain non-major autoregressive sub-patterns have high media capabilities in the financial time series. Different stock indexes exhibit similar characteristics in the transmission of fluctuation information. This work not only proposes a distinctive perspective for analysing financial time series but also provides important information for investors.

  6. Characteristics of the transmission of autoregressive sub-patterns in financial time series

    PubMed Central

    Gao, Xiangyun; An, Haizhong; Fang, Wei; Huang, Xuan; Li, Huajiao; Zhong, Weiqiong

    2014-01-01

    There are many types of autoregressive patterns in financial time series, and they form a transmission process. Here, we define autoregressive patterns quantitatively through an econometrical regression model. We present a computational algorithm that sets the autoregressive patterns as nodes and transmissions between patterns as edges, and then converts the transmission process of autoregressive patterns in a time series into a network. We utilised daily Shanghai (securities) composite index time series to study the transmission characteristics of autoregressive patterns. We found statistically significant evidence that the financial market is not random and that there are similar characteristics between parts and whole time series. A few types of autoregressive sub-patterns and transmission patterns drive the oscillations of the financial market. A clustering effect on fluctuations appears in the transmission process, and certain non-major autoregressive sub-patterns have high media capabilities in the financial time series. Different stock indexes exhibit similar characteristics in the transmission of fluctuation information. This work not only proposes a distinctive perspective for analysing financial time series but also provides important information for investors. PMID:25189200

  7. Nursing staff work patterns in a residential aged care home: a time-motion study.

    PubMed

    Qian, Siyu; Yu, Ping; Hailey, David

    2016-11-01

    Objective Residential aged care services are challenged by an increasing number of residents and a shortage of nursing staff. Developing strategies to overcome this challenge requires an understanding of nursing staff work patterns. The aim of the present study was to investigate the work processes followed by nursing staff and how nursing time is allocated in a residential aged care home. Methods An observational time-motion study was conducted at two aged care units for 12 morning shifts. Seven nurses were observed, one per shift. Results In all, there were 91h of observation. The results showed that there was a common work process followed by all nurse participants. Medication administration, documentation and verbal communication were the most time-consuming activities and were conducted most frequently. No significant difference between the two units was found in any category of activities. The average duration of most activities was less than 1min. There was no difference in time utilisation between the endorsed enrolled nurses and the personal carers in providing nursing care. Conclusion Medication administration, documentation and verbal communication were the major tasks in morning shifts in a residential aged care home. Future research can investigate how verbal communication supports nursing care. What is known about the topic? The aging population will substantially increase the demand for residential aged care services. There is a lack of research on nurses' work patterns in residential aged care homes. What does this paper add? The present study provides a comprehensive understanding of nurses' work patterns in a residential aged care home. There is a common work process followed by nurses in providing nursing care. Medication administration, verbal communication and documentation are the most time-consuming activities and they are frequently conducted in the same period of time. Wound care, physical review and documentation on desktop computers are arranged flexibly by the nurses. What are the implications for practitioners? When developing a task reallocation strategy to improve work efficiency, effort can be put into tasks that can be arranged more flexibly.

  8. Working Time in Comparative Perspective. Volume I: Patterns, Trends, and the Policy Implications for Earnings Inequality and Unemployment.

    ERIC Educational Resources Information Center

    Wong, Ging, Ed.; Picot, Garnett, Ed.

    This is the first of two volumes of selected papers presented at the 1996 conference on "Changes in Working Time in Canada and the United States." Eleven chapters focus on weekly hours worked by individuals, including the recent changes in the distribution of weekly working time in Canada and the U.S., implications of the changing…

  9. Academic Life: Monitoring Work Patterns and Daily Activities

    ERIC Educational Resources Information Center

    Forgasz, Helen J.; Leder, Gilah C.

    2006-01-01

    Academics are reported to be working longer hours and have less time for research because of increasing administrative and teaching demands. The traditional pattern of the academic enterprise appears to have changed. To explore whether this is indeed the case, the Experience Sampling Method [ESM], a research technique devised by Mihaly…

  10. Converging Work-Talk Patterns in Online Task-Oriented Communities.

    PubMed

    Xuan, Qi; Devanbu, Premkumar; Filkov, Vladimir

    2016-01-01

    Much of what we do is accomplished by working collaboratively with others, and a large portion of our lives are spent working and talking; the patterns embodied in the alternation of working and talking can provide much useful insight into task-oriented social behaviors. The available electronic traces of the different kinds of human activities in online communities are an empirical goldmine that can enable the holistic study and understanding of these social systems. Open Source Software (OSS) projects are prototypical examples of collaborative, task-oriented communities, depending on volunteers for high-quality work. Here, we use sequence analysis methods to identify the work-talk patterns of software developers in online communities of Open Source Software projects. We find that software developers prefer to persist in same kinds of activities, i.e., a string of work activities followed by a string of talk activities and so forth, rather than switch them frequently; this tendency strengthens with time, suggesting that developers become more efficient, and can work longer with fewer interruptions. This process is accompanied by the formation of community culture: developers' patterns in the same communities get closer with time while different communities get relatively more different. The emergence of community culture is apparently driven by both "talk" and "work". Finally, we also find that workers with good balance between "work" and "talk" tend to produce just as much work as those that focus strongly on "work"; however, the former appear to be more likely to continue to be active contributors in the communities.

  11. 78 FR 45567 - Proposed Collection, Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-29

    ... eating patterns, physical activity, and BMI; time- use patterns of food assistance program participants.... It measures, for example, time spent with children, working, sleeping, or doing leisure activities... comparisons of production between nations that have different mixes of market and non-market activities. The...

  12. Information and Complexity Measures Applied to Observed and Simulated Soil Moisture Time Series

    USDA-ARS?s Scientific Manuscript database

    Time series of soil moisture-related parameters provides important insights in functioning of soil water systems. Analysis of patterns within these time series has been used in several studies. The objective of this work was to compare patterns in observed and simulated soil moisture contents to u...

  13. The Division of Labor and Leisure in Modern Society: A New Form of Solidarity.

    ERIC Educational Resources Information Center

    Bosserman, Phillip

    The paper suggests that new values created by modern forms of leisure have intersected with critical changes in the work structure to form a new social pattern. The new pattern emerges from a crisis in industrial societies. Factors which have created this crisis include the rupture of the time frames of society (how work and non-work are…

  14. The time course of cancer detection performance

    NASA Astrophysics Data System (ADS)

    Taylor-Phillips, Sian; Clarke, Aileen; Wallis, Matthew; Wheaton, Margot; Duncan, Alison; Gale, Alastair G.

    2011-03-01

    The purpose of this study was to measure how mammography readers' performance varies with time of day and time spent reading. This was investigated in screening practice and when reading an enriched case set. In screening practice records of time and date that each case was read, along with outcome (whether the woman was recalled for further tests, and biopsy results where performed) was extracted from records from one breast screening centre in UK (4 readers). Patterns of performance with time spent reading was also measured using an enriched test set (160 cases, 41% malignant, read three times by eight radiologists). Recall rates varied with time of day, with different patterns for each reader. Recall rates decreased as the reading session progressed both when reading the enriched test set and in screening practice. Further work is needed to expand this work to a greater number of breast screening centres, and to determine whether these patterns of performance over time can be used to optimize overall performance.

  15. Employment Patterns of Less-Skilled Workers: Links to Children’s Behavior and Academic Progress

    PubMed Central

    Kalil, Ariel; Dunifon, Rachel E.

    2012-01-01

    Using data from five waves of the Women’s Employment Survey (WES; 1997–2003), we examine the links between low-income mothers’ employment patterns and the emotional behavior and academic progress of their children. We find robust and substantively important linkages between several different dimensions of mothers’ employment experiences and child outcomes. The pattern of results is similar across empirical approaches—including ordinary least squares and child fixed-effect models, with and without an extensive set of controls. Children exhibit fewer behavior problems when mothers work and experience job stability (relative to children whose mothers do not work). In contrast, maternal work accompanied by job instability is associated with significantly higher child behavior problems (relative to employment in a stable job). Children whose mothers work full-time and/or have fluctuating work schedules also exhibit significantly higher levels of behavior problems. However, full-time work has negative consequences for children only when it is in jobs that do not require cognitive skills. Such negative consequences are completely offset when this work experience is in jobs that require the cognitive skills that lead to higher wage growth prospects. Finally, fluctuating work schedules and full-time work in non-cognitively demanding jobs are each strongly associated with the probability that the child will repeat a grade or be placed in special education. PMID:22246798

  16. Factors associated with less-than-full-time working in medical practice: results of surveys of five cohorts of UK doctors, 10 years after graduation.

    PubMed

    Lachish, Shelly; Svirko, Elena; Goldacre, Michael J; Lambert, Trevor

    2016-10-13

    The greater participation of women in medicine in recent years, and recent trends showing that doctors of both sexes work fewer hours than in the past, present challenges for medical workforce planning. In this study, we provide a detailed analysis of the characteristics of doctors who choose to work less-than-full-time (LTFT). We aimed to determine the influence of these characteristics on the probability of working LTFT. We used data on working patterns obtained from long-term surveys of 10,866 UK-trained doctors. We analysed working patterns at 10 years post-graduation for doctors of five graduating cohorts, 1993, 1996, 1999, 2000 and 2002 (i.e. in the years 2003, 2006, 2009, 2010 and 2012, respectively). We used multivariable binary logistic regression models to examine the influence of a number of personal and professional characteristics on the likelihood of working LTFT in male and female doctors. Across all cohorts, 42 % of women and 7 % of men worked LTFT. For female doctors, having children significantly increased the likelihood of working LTFT, with greater effects observed for greater numbers of children and for female doctors in non-primary care specialties (non-GPs). While >40 % of female GPs with children worked LTFT, only 10 % of female surgeons with children did so. Conversely, the presence of children had no effect on male working patterns. Living with a partner increased the odds of LTFT working in women doctors, but decreased the odds of LTFT working in men (independently of children). Women without children were no more likely to work LTFT than were men (with or without children). For both women and men, the highest rates of LTFT working were observed among GPs (~10 and 6 times greater than non-GPs, respectively), and among those not in training or senior positions. Family circumstances (children and partner status) affect the working patterns of women and men differently, but both sexes respond similarly to the constraints of their clinical specialty and seniority. Thus, although women doctors comprise the bulk of LTFT workers, gender is just one of several determinants of doctors' working patterns, and wanting to work LTFT is evidently not solely an issue for working mothers.

  17. Objectively Measured Patterns of Activities of Different Intensity Categories and Steps Taken Among Working Adults in a Multi-ethnic Asian Population.

    PubMed

    Müller-Riemenschneider, Falk; Ng, Sheryl Hui Xian; Koh, David; Chu, Anne Hin Yee

    2016-06-01

    To objectively assess sedentary behavior (SB), light- and moderate-to-vigorous intensity physical activity (MVPA), and steps among Singaporean office-based workers across days of the week. A convenience sample of office-based employees of a public University was recruited. Time spent for SB, light-, and MVPA using different validated accelerometry counts per minute (CPM), and step count were determined. Depending on applied CPM for SB (less than 100, less than 150 and less than 200 CPM), 107 working adults spent between 69.2% and 76.4% of their daily wakeful time in SB. Time spent in SB and MVPA were higher on weekdays than weekends. The hourly analysis highlights patterns of greater SB during usual working hours on weekdays but not on weekends. SB at work contributes greatly toward total daily sitting time. Low PA levels and high SB levels were found on weekends.

  18. The Impact of Part-Time Jobs in Years 12 and 13 on Qualification Achievement.

    ERIC Educational Resources Information Center

    Payne, Joan

    2003-01-01

    Presents data from nationally representative sample of the England/Wales Youth Cohort Study, describing patterns of paid work among full-time students in Years 12/13 working for qualifications. Shows paid work of a few hours has negligible impact on "A" level grades, but long working hours significantly reduce grades. (BT)

  19. Visual and Spatial Working Memory Are Not that Dissociated after All: A Time-Based Resource-Sharing Account

    ERIC Educational Resources Information Center

    Vergauwe, Evie; Barrouillet, Pierre; Camos, Valerie

    2009-01-01

    Examinations of interference between visual and spatial materials in working memory have suggested domain- and process-based fractionations of visuo-spatial working memory. The present study examined the role of central time-based resource sharing in visuo-spatial working memory and assessed its role in obtained interference patterns. Visual and…

  20. An Efficient Pattern Mining Approach for Event Detection in Multivariate Temporal Data

    PubMed Central

    Batal, Iyad; Cooper, Gregory; Fradkin, Dmitriy; Harrison, James; Moerchen, Fabian; Hauskrecht, Milos

    2015-01-01

    This work proposes a pattern mining approach to learn event detection models from complex multivariate temporal data, such as electronic health records. We present Recent Temporal Pattern mining, a novel approach for efficiently finding predictive patterns for event detection problems. This approach first converts the time series data into time-interval sequences of temporal abstractions. It then constructs more complex time-interval patterns backward in time using temporal operators. We also present the Minimal Predictive Recent Temporal Patterns framework for selecting a small set of predictive and non-spurious patterns. We apply our methods for predicting adverse medical events in real-world clinical data. The results demonstrate the benefits of our methods in learning accurate event detection models, which is a key step for developing intelligent patient monitoring and decision support systems. PMID:26752800

  1. Efficiency and Equity in the Time Pattern of Teacher Pension Benefits: An Analysis of Four State Systems. Working Paper 2007-01

    ERIC Educational Resources Information Center

    Costrell, Robert M.; Podgursky, Michael J.

    2007-01-01

    Defined Benefit pension plans often generate odd time patterns of benefits. One typical pattern exhibits low accrual in early years, accelerating in mid-late years, followed by dramatic decline, or even negative returns in years that are relatively young for retirement. We consider four states for specific analysis: Arkansas, Missouri, California…

  2. Optical measurement of sound using time-varying laser speckle patterns

    NASA Astrophysics Data System (ADS)

    Leung, Terence S.; Jiang, Shihong; Hebden, Jeremy

    2011-02-01

    In this work, we introduce an optical technique to measure sound. The technique involves pointing a coherent pulsed laser beam on the surface of the measurement site and capturing the time-varying speckle patterns using a CCD camera. Sound manifests itself as vibrations on the surface which induce a periodic translation of the speckle pattern over time. Using a parallel speckle detection scheme, the dynamics of the time-varying speckle patterns can be captured and processed to produce spectral information of the sound. One potential clinical application is to measure pathological sounds from the brain as a screening test. We performed experiments to demonstrate the principle of the detection scheme using head phantoms. The results show that the detection scheme can measure the spectra of single frequency sounds between 100 and 2000 Hz. The detection scheme worked equally well in both a flat geometry and an anatomical head geometry. However, the current detection scheme is too slow for use in living biological tissues which has a decorrelation time of a few milliseconds. Further improvements have been suggested.

  3. Changes in Work Patterns: A Synthesis of Five National Reports on the Service Sector. France, Germany, Japan, Sweden, the United States.

    ERIC Educational Resources Information Center

    Organisation for Economic Cooperation and Development, Paris (France). Centre for Educational Research and Innovation.

    An analysis of the service sector in five countries (France, Germany, Japan, Sweden, and the United States) was made through synthesis of earlier research on work patterns in the countries. Some of the findings and issues discovered concerned the following: (1) the heterogeneity of the service sector; (2) the progress of part-time work; (3)…

  4. The work patterns of lactating women in Madura.

    PubMed

    Launer, L J

    1993-08-01

    Little is known about the work patterns of mildly malnourished lactating women: are they modified to accommodate the demands of lactation? What factors influence their pattern of work during this period of nutritional stress? These questions were addressed using quantitative and qualitative data collected from 36 randomly selected women living in a poor community in Madura, Indonesia. Work patterns of the lactating women and their family members were documented for the first 12 months post-partum. Changes in work activity were analysed within four time periods corresponding to Madurese views on development during infancy: the vulnerable neonatal (birth-40 days), early (6-12 wk) and mid (13-31 wk) stages and the independent late (32-54 wk) stage. Quantitative data suggest that women did adjust work patterns to accommodate the demands of lactation and that these adjustments went beyond the neonatal stage. Mothers curtailed their participation in high- and low-energy income-generating activities, modified their conditions of work to promote maternal-infant proximity and conserved energy while performing specific activities. These patterns were most common through the mid infancy stage. Data are presented that describe how cultural values supporting maternal-infant proximity, intra- and inter-familial work exchanges, season and resources played a role in the type of accommodations mothers were able to make to breast-feed. These data suggest that even in relatively poor environments alterations in work patterns that may be favourable to lactation are possible, particularly when cultural concepts of infancy support such a trade-off.

  5. Patterns of variations in large pelagic fish: A comparative approach between the Indian and the Atlantic Oceans

    NASA Astrophysics Data System (ADS)

    Corbineau, A.; Rouyer, T.; Fromentin, J.-M.; Cazelles, B.; Fonteneau, A.; Ménard, F.

    2010-07-01

    Catch data of large pelagic fish such as tuna, swordfish and billfish are highly variable ranging from short to long term. Based on fisheries data, these time series are noisy and reflect mixed information on exploitation (targeting, strategy, fishing power), population dynamics (recruitment, growth, mortality, migration, etc.), and environmental forcing (local conditions or dominant climate patterns). In this work, we investigated patterns of variation of large pelagic fish (i.e. yellowfin tuna, bigeye tuna, swordfish and blue marlin) in Japanese longliners catch data from 1960 to 2004. We performed wavelet analyses on the yearly time series of each fish species in each biogeographic province of the tropical Indian and Atlantic Oceans. In addition, we carried out cross-wavelet analyses between these biological time series and a large-scale climatic index, i.e. the Southern Oscillation Index (SOI). Results showed that the biogeographic province was the most important factor structuring the patterns of variability of Japanese catch time series. Relationships between the SOI and the fish catches in the Indian and Atlantic Oceans also pointed out the role of climatic variability for structuring patterns of variation of catch time series. This work finally confirmed that Japanese longline CPUE data poorly reflect the underlying population dynamics of tunas.

  6. Timing of Return to Work and Breastfeeding in Australia.

    PubMed

    Xiang, Ning; Zadoroznyj, Maria; Tomaszewski, Wojtek; Martin, Bill

    2016-06-01

    To examine the effects of timing of return to work, number of hours worked, and their interaction, on the likelihood of breastfeeding at 6 months and predominant breastfeeding at 16 weeks. A nationally representative sample of Australian mothers in paid employment in the 13 months before giving birth (n = 2300) were surveyed by telephone. Four multivariate logistic regression models were used to analyze the effects of timing of return to work and work hours, independently and in interaction, on any breastfeeding at 6 months and on predominant breastfeeding at 16 weeks, controlling for maternal sociodemographics, employment patterns, and health measures. Mothers who returned to work within 6 months and who worked for ≥20 hours per week were significantly less likely than mothers who had not returned to work to be breastfeeding at 6 months. However, returning to work for ≤19 hours per week had no significant impact on the likelihood of breastfeeding regardless of when mothers returned to work. Older maternal age, higher educational attainment, better physical or mental health, managerial or professional maternal occupation, and being self-employed all significantly contributed to the increased likelihood of any breastfeeding at 6 months. Similar patterns exist for predominant breastfeeding at 16 weeks. The effects of timing of return to work are secondary to the hours of employment. Working ≤19 hours per week is associated with higher likelihood of maintaining breastfeeding, regardless of timing of return to work. Copyright © 2016 by the American Academy of Pediatrics.

  7. Patterns of salivary cortisol levels can manifest work stress in emergency care providers.

    PubMed

    Nakajima, Yasushi; Takahashi, Takayuki; Shetty, Vivek; Yamaguchi, Masaki

    2012-05-01

    To develop objective assessments of work fatigue, we investigated the patterns of changes in salivary cortisol levels in emergency care providers working extended work shifts. Fourteen subjects, comprising seven physicians and seven physician assistants, provided unstimulated saliva samples at regular intervals over the course of a 24-h work shift and over their subsequent free day. There was a significant time effect, with early morning cortisol levels being significantly attenuated following the work shift. Native diurnal variations varied by gender, with the female subjects manifesting greater cortisol levels. Physicians also had higher cortisol profiles even though their wake-rest cycles were similar to those of the physician assistants. Our results suggest that temporal changes, as well as diurnal similarities, in the salivary cortisol patterns can reflect work-related stress and recovery. In particular, early morning cortisol levels may manifest individual reactivity to work stressors as well as sleep deprivation.

  8. Has the impact of the working time regulations changed neurosurgical trainees' attitudes towards the European working time directive 5 years on?

    PubMed

    Cowie, Christopher J A; Pešić-Smith, Jonathan D; Boukas, Alexandros; Nelson, Richard J

    2013-10-01

    We report the results from a survey of the British Neurosurgical Trainees' Association which aimed to assess current rota patterns and their compliance with the government's working time regulations. The survey questioned whether trainees felt that shift working, imposed as a result of the European working time directive, is continuing to impact on patient care and training opportunities in neurosurgery. The responses to this survey indicate that neurosurgical trainees remain concerned with the impact that the current working time regulations have on all facets of their work: training, work- life balance, and the provision of patient care. The survey comments show that the majority would support a change in legislation to allow greater flexibility in the working time regulations.

  9. Differences in Low and High Working-Memory Capacity Readers' Cognitive and Metacognitive Processing Patterns as a Function of Reading for Different Purposes

    ERIC Educational Resources Information Center

    Linderholm, Tracy; Cong, Xiaosi; Zhao, Qin

    2008-01-01

    Differences in cognitive and metacognitive processing patterns as a function of working-memory capacity and reading for different purposes were examined in college-aged readers by collecting reading times and calculating absolute monitoring accuracy, which is the difference between estimated and actual comprehension test performance. Readers read…

  10. GrammarViz 3.0: Interactive Discovery of Variable-Length Time Series Patterns

    DOE PAGES

    Senin, Pavel; Lin, Jessica; Wang, Xing; ...

    2018-02-23

    The problems of recurrent and anomalous pattern discovery in time series, e.g., motifs and discords, respectively, have received a lot of attention from researchers in the past decade. However, since the pattern search space is usually intractable, most existing detection algorithms require that the patterns have discriminative characteristics and have its length known in advance and provided as input, which is an unreasonable requirement for many real-world problems. In addition, patterns of similar structure, but of different lengths may co-exist in a time series. In order to address these issues, we have developed algorithms for variable-length time series pattern discoverymore » that are based on symbolic discretization and grammar inference—two techniques whose combination enables the structured reduction of the search space and discovery of the candidate patterns in linear time. In this work, we present GrammarViz 3.0—a software package that provides implementations of proposed algorithms and graphical user interface for interactive variable-length time series pattern discovery. The current version of the software provides an alternative grammar inference algorithm that improves the time series motif discovery workflow, and introduces an experimental procedure for automated discretization parameter selection that builds upon the minimum cardinality maximum cover principle and aids the time series recurrent and anomalous pattern discovery.« less

  11. GrammarViz 3.0: Interactive Discovery of Variable-Length Time Series Patterns

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Senin, Pavel; Lin, Jessica; Wang, Xing

    The problems of recurrent and anomalous pattern discovery in time series, e.g., motifs and discords, respectively, have received a lot of attention from researchers in the past decade. However, since the pattern search space is usually intractable, most existing detection algorithms require that the patterns have discriminative characteristics and have its length known in advance and provided as input, which is an unreasonable requirement for many real-world problems. In addition, patterns of similar structure, but of different lengths may co-exist in a time series. In order to address these issues, we have developed algorithms for variable-length time series pattern discoverymore » that are based on symbolic discretization and grammar inference—two techniques whose combination enables the structured reduction of the search space and discovery of the candidate patterns in linear time. In this work, we present GrammarViz 3.0—a software package that provides implementations of proposed algorithms and graphical user interface for interactive variable-length time series pattern discovery. The current version of the software provides an alternative grammar inference algorithm that improves the time series motif discovery workflow, and introduces an experimental procedure for automated discretization parameter selection that builds upon the minimum cardinality maximum cover principle and aids the time series recurrent and anomalous pattern discovery.« less

  12. Patterns of time use among low-income urban minority adolescents and associations with academic outcomes and problem behaviors.

    PubMed

    Wolf, Sharon; Aber, J Lawrence; Morris, Pamela A

    2015-06-01

    Time budgets represent key opportunities for developmental support and contribute to an understanding of achievement gaps and adjustment across populations of youth. This study assessed the connection between out-of-school time use patterns and academic performance outcomes, academic motivations and goals, and problem behaviors for 504 low-income urban African American and Latino adolescents (54% female; M = 16.6 years). Time use patterns were measured across eight activity types using cluster analysis. Four groups of adolescents were identified, based on their different profiles of time use: (1) Academic: those with most time in academic activities; (2) Social: those with most time in social activities; (3) Maintenance/work: those with most time in maintenance and work activities; and (4) TV/computer: those with most time in TV or computer activities. Time use patterns were meaningfully associated with variation in outcomes in this population. Adolescents in the Academic cluster had the highest levels of adjustment across all domains; adolescents in the Social cluster had the lowest academic performance and highest problem behaviors; and adolescents in the TV/computer cluster had the lowest levels of intrinsic motivation. Females were more likely to be in the Academic cluster, and less likely to be in the other three clusters compared to males. No differences by race or gender were found in assessing the relationship between time use and outcomes. The study's results indicate that time use patterns are meaningfully associated with within-group variation in adjustment for low-income minority adolescents, and that shared contexts may shape time use more than individual differences in race/ethnicity for this population.

  13. Workdays, in-between workdays and the weekend: a diary study on effort and recovery.

    PubMed

    van Hooff, Madelon L M; Geurts, Sabine A E; Kompier, Michiel A J; Taris, Toon W

    2007-07-01

    Effort-recovery theory (Meijman and Mulder in Handbook of work and organizational psychology, Psychology Press/Erlbaum, Hove, pp 5-33, 1998) proposes that effort expenditure may have adverse consequences for health in the absence of sufficient recovery opportunities. Thus, insight in the relationships between effort and recovery is imperative to understand work-related health. This study therefore focused on the relation between work-related effort and recovery (1) during workdays, (2) in-between workdays and (3) in the weekend. For these three time periods, we compared a group of employees reporting relatively low levels of work-related effort ("low-effort group") and a group of employees reporting relatively high levels of work-related effort ("high-effort group") with respect to (1) activity patterns, (2) the experience of these activity patterns, and (3) health and well-being indicators. Data were collected among university staff members. Participants (N(high-effort group) = 24 and N(low-effort group) = 27) completed a general questionnaire and took part in a 7-day daily diary study covering five weekdays and the following weekend. Differences between the two effort-groups were examined by means of analysis of variance. Compared to the low-effort group, the high-effort group (1) engaged less often in active leisure activities during the week and worked more overtime in the weekend, (2) considered both work and home activities as more effortful, but not as less pleasurable, and (3) reported higher levels of sleep complaints (weekdays only) and fatigue, more preoccupation with work (weekdays only) and lower motivation to start the next workweek during the weekend. Work-related effort is associated with various aspects of work time and (potential) recovery time in-between workdays and in the weekend. High levels of work-related effort are associated with activity patterns that are less beneficial in terms of recovery, with higher effort expenditure during and after work time, and with diminished health and well-being.

  14. Women in dentistry in South Africa: a survey of their experiences and opinions.

    PubMed

    Naidoo, S

    2005-08-01

    Women form an increasingly important part of the dentally trained workforce in South Africa. However, little is known about the professional issues and work-related problems affecting women dentists. A postal survey was undertaken of registered female dental practitioners in the country, with the aim to document their experiences. The survey (i) ascertained their current pattern of work, (ii) identified factors influencing their work patterns and (iii) identified factors that would help women remain in the profession or re-enter it more easily after an absence. A self-administered 50-item questionnaire containing open and closed-ended questions was used. Questions related to professional status, working patterns, practice ownership, postgraduate qualifications and career satisfaction. Nine hundred and sixty questionnaires were sent out and 280 were returned (29% response rate). Although a significant majority were currently practicing (96%), about 20% were employed or worked part-time and 7 reported that they were not in practice at the time of the survey for various reasons including maternity leave, ill-health, retirement or that they were now working outside the dental field. Major factors identified in this study were the women's dual responsibility at home and at work. Few women find themselves in specialist practice, although 68% indicated that they would liked to have specialised. Home responsibilities and inflexible working conditions were commonly reported difficulties experienced with further studies. In addition, the lack of part-time training and the geographical location of training facilities also played a role. Women dentists need more flexible working schedules and conditions of employment. Part-time training and part-time career options should be extended. Retraining and refresher courses for Women dentists who have had a break in their careers should be available to enable them to return sooner and more easily to practice. Tertiary training dental facilities throughout the country should take up this challenge and run courses that are tailored to the local need and domestic commitments of the women involved.

  15. National Medical Care System May Impede Fostering of True Specialization of Radiation Oncologists: Study Based on Structure Survey in Japan

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Numasaki, Hodaka; Shibuya, Hitoshi; Nishio, Masamichi

    2012-01-01

    Purpose: To evaluate the actual work environment of radiation oncologists (ROs) in Japan in terms of working pattern, patient load, and quality of cancer care based on the relative time spent on patient care. Methods and Materials: In 2008, the Japanese Society of Therapeutic Radiology and Oncology produced a questionnaire for a national structure survey of radiation oncology in 2007. Data for full-time ROs were crosschecked with data for part-time ROs by using their identification data. Data of 954 ROs were analyzed. The relative practice index for patients was calculated as the relative value of care time per patient onmore » the basis of Japanese Blue Book guidelines (200 patients per RO). Results: The working patterns of RO varied widely among facility categories. ROs working mainly at university hospitals treated 189.2 patients per year on average, with those working in university hospitals and their affiliated facilities treating 249.1 and those working in university hospitals only treating 144.0 patients per year on average. The corresponding data were 256.6 for cancer centers and 176.6 for other facilities. Geographically, the mean annual number of patients per RO per quarter was significantly associated with population size, varying from 143.1 to 203.4 (p < 0.0001). There were also significant differences in the average practice index for patients by ROs working mainly in university hospitals between those in main and affiliated facilities (1.07 vs 0.71: p < 0.0001). Conclusions: ROs working in university hospitals and their affiliated facilities treated more patients than the other ROs. In terms of patient care time only, the quality of cancer care in affiliated facilities might be worse than that in university hospitals. Under the current national medical system, working patterns of ROs of academic facilities in Japan appear to be problematic for fostering true specialization of radiation oncologists.« less

  16. National medical care system may impede fostering of true specialization of radiation oncologists: study based on structure survey in Japan.

    PubMed

    Numasaki, Hodaka; Shibuya, Hitoshi; Nishio, Masamichi; Ikeda, Hiroshi; Sekiguchi, Kenji; Kamikonya, Norihiko; Koizumi, Masahiko; Tago, Masao; Ando, Yutaka; Tsukamoto, Nobuhiro; Terahara, Atsuro; Nakamura, Katsumasa; Mitsumori, Michihide; Nishimura, Tetsuo; Hareyama, Masato; Teshima, Teruki

    2012-01-01

    To evaluate the actual work environment of radiation oncologists (ROs) in Japan in terms of working pattern, patient load, and quality of cancer care based on the relative time spent on patient care. In 2008, the Japanese Society of Therapeutic Radiology and Oncology produced a questionnaire for a national structure survey of radiation oncology in 2007. Data for full-time ROs were crosschecked with data for part-time ROs by using their identification data. Data of 954 ROs were analyzed. The relative practice index for patients was calculated as the relative value of care time per patient on the basis of Japanese Blue Book guidelines (200 patients per RO). The working patterns of RO varied widely among facility categories. ROs working mainly at university hospitals treated 189.2 patients per year on average, with those working in university hospitals and their affiliated facilities treating 249.1 and those working in university hospitals only treating 144.0 patients per year on average. The corresponding data were 256.6 for cancer centers and 176.6 for other facilities. Geographically, the mean annual number of patients per RO per quarter was significantly associated with population size, varying from 143.1 to 203.4 (p < 0.0001). There were also significant differences in the average practice index for patients by ROs working mainly in university hospitals between those in main and affiliated facilities (1.07 vs 0.71: p < 0.0001). ROs working in university hospitals and their affiliated facilities treated more patients than the other ROs. In terms of patient care time only, the quality of cancer care in affiliated facilities might be worse than that in university hospitals. Under the current national medical system, working patterns of ROs of academic facilities in Japan appear to be problematic for fostering true specialization of radiation oncologists. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. The impact of perceived intensity and frequency of police work occupational stressors on the cortisol awakening response (CAR): Findings from the BCOPS study.

    PubMed

    Violanti, John M; Fekedulegn, Desta; Andrew, Michael E; Hartley, Tara A; Charles, Luenda E; Miller, Diane B; Burchfiel, Cecil M

    2017-01-01

    Police officers encounter unpredictable, evolving, and escalating stressful demands in their work. Utilizing the Spielberger Police Stress Survey (60-item instrument for assessing specific conditions or events considered to be stressors in police work), the present study examined the association of the top five highly rated and bottom five least rated work stressors among police officers with their awakening cortisol pattern. Participants were police officers enrolled in the Buffalo Cardio-Metabolic Occupational Police Stress (BCOPS) study (n=338). For each group, the total stress index (product of rating and frequency of the stressor) was calculated. Participants collected saliva by means of Salivettes at four time points: on awakening, 15, 30 and 45min after waking to examine the cortisol awakening response (CAR). Saliva samples were analyzed for free cortisol concentrations. A slope reflecting the awakening pattern of cortisol over time was estimated by fitting a linear regression model relating cortisol in log-scale to time of collection. The slope served as the outcome variable. Analysis of covariance, regression, and repeated measures models were used to determine if there was an association of the stress index with the waking cortisol pattern. There was a significant negative linear association between total stress index of the five highest stressful events and slope of the awakening cortisol regression line (trend p-value=0.0024). As the stress index increased, the pattern of the awakening cortisol regression line tended to flatten. Officers with a zero stress index showed a steep and steady increase in cortisol from baseline (which is often observed) while officers with a moderate or high stress index showed a dampened or flatter response over time. Conversely, the total stress index of the five least rated events was not significantly associated with the awakening cortisol pattern. The study suggests that police events or conditions considered highly stressful by the officers may be associated with disturbances of the typical awakening cortisol pattern. The results are consistent with previous research where chronic exposure to stressors is associated with a diminished awakening cortisol response pattern. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. The impact of perceived intensity and frequency of police work occupational stressors on the cortisol awakening response (CAR): Findings from the BCOPS study

    PubMed Central

    Violanti, John M.; Fekedulegn, Desta; Andrew, Michael E.; Hartley, Tara A.; Charles, Luenda E.; Miller, Diane B.; Burchfiel, Cecil M.

    2016-01-01

    Police officers encounter unpredictable, evolving, and escalating stressful demands in their work. Utilizing the Spielberger Police Stress Survey (60-item instrument for assessing specific conditions or events considered to be stressors in police work), the present study examined the association of the top five highly rated and bottom five least rated work stressors among police officers with their awakening cortisol pattern. Participants were police officers enrolled in the Buffalo Cardio-Metabolic Occupational Police Stress (BCOPS) study (n = 338). For each group, the total stress index (product of rating and frequency of the stressor) was calculated. Participants collected saliva by means of Salivettes at four time points: on awakening, 15, 30 and 45 min after waking to examine the cortisol awakening response (CAR). Saliva samples were analyzed for free cortisol concentrations. A slope reflecting the awakening pattern of cortisol over time was estimated by fitting a linear regression model relating cortisol in log-scale to time of collection. The slope served as the outcome variable. Analysis of covariance, regression, and repeated measures models were used to determine if there was an association of the stress index with the waking cortisol pattern. There was a significant negative linear association between total stress index of the five highest stressful events and slope of the awakening cortisol regression line (trend p-value = 0.0024). As the stress index increased, the pattern of the awakening cortisol regression line tended to flatten. Officers with a zero stress index showed a steep and steady increase in cortisol from baseline (which is often observed) while officers with a moderate or high stress index showed a dampened or flatter response over time. Conversely, the total stress index of the five least rated events was not significantly associated with the awakening cortisol pattern. The study suggests that police events or conditions considered highly stressful by the officers may be associated with disturbances of the typical awakening cortisol pattern. The results are consistent with previous research where chronic exposure to stressors is associated with a diminished awakening cortisol response pattern. PMID:27816820

  19. Arrival and Departure Patterns of Public Sector Employees before and after Implementation of Flexitime.

    ERIC Educational Resources Information Center

    Ronen, Simcha

    1981-01-01

    Examined the effects of a flexible working hours schedule on the arrival and departure times of 162 public sector employees. Results indicated that workers, when scheduling their own workday, deviate only moderately from their preflexitime arrival/departure times; and they tend to develop relatively stable arrival/departure patterns. (Author/RC)

  20. Lifetime Learning Trajectories: Close Encounters of Five Kinds. Patterns of Participation in Adult Education and Training. Working Paper 7.

    ERIC Educational Resources Information Center

    Gorard, Stephen; Rees, Gareth; Fevre, Ralph; Furlong, John

    This working paper is a product of a regional study in industrial South Wales of the determinants of participation and non-participation in post-compulsory education and training, with special reference to processes of change in the patterns of these determinants over time and to variations between geographical areas. This paper describes the…

  1. The Interplay between Women's Life Course Work Patterns and Financial Planning for Later Life

    ERIC Educational Resources Information Center

    Berger, Ellie D.; Denton, Margaret A.

    2004-01-01

    In order to gain a comprehensive understanding of the interplay between women's life course work patterns and their financial planning for later life, we examined data from semi-structured interviews with retired women (n = 28) aged 59 to 92. The majority of women disrupted their careers at some point in time, for an average of 14 years, primarily…

  2. Numerical comparison of grid pattern diffraction effects through measurement and modeling with OptiScan software

    NASA Astrophysics Data System (ADS)

    Murray, Ian B.; Densmore, Victor; Bora, Vaibhav; Pieratt, Matthew W.; Hibbard, Douglas L.; Milster, Tom D.

    2011-06-01

    Coatings of various metalized patterns are used for heating and electromagnetic interference (EMI) shielding applications. Previous work has focused on macro differences between different types of grids, and has shown good correlation between measurements and analyses of grid diffraction. To advance this work, we have utilized the University of Arizona's OptiScan software, which has been optimized for this application by using the Babinet Principle. When operating on an appropriate computer system, this algorithm produces results hundreds of times faster than standard Fourier-based methods, and allows realistic cases to be modeled for the first time. By using previously published derivations by Exotic Electro-Optics, we compare diffraction performance of repeating and randomized grid patterns with equivalent sheet resistance using numerical performance metrics. Grid patterns of each type are printed on optical substrates and measured energy is compared against modeled energy.

  3. Exploring universal patterns in human home-work commuting from mobile phone data.

    PubMed

    Kung, Kevin S; Greco, Kael; Sobolevsky, Stanislav; Ratti, Carlo

    2014-01-01

    Home-work commuting has always attracted significant research attention because of its impact on human mobility. One of the key assumptions in this domain of study is the universal uniformity of commute times. However, a true comparison of commute patterns has often been hindered by the intrinsic differences in data collection methods, which make observation from different countries potentially biased and unreliable. In the present work, we approach this problem through the use of mobile phone call detail records (CDRs), which offers a consistent method for investigating mobility patterns in wholly different parts of the world. We apply our analysis to a broad range of datasets, at both the country (Portugal, Ivory Coast, and Saudi Arabia), and city (Boston) scale. Additionally, we compare these results with those obtained from vehicle GPS traces in Milan. While different regions have some unique commute time characteristics, we show that the home-work time distributions and average values within a single region are indeed largely independent of commute distance or country (Portugal, Ivory Coast, and Boston)-despite substantial spatial and infrastructural differences. Furthermore, our comparative analysis demonstrates that such distance-independence holds true only if we consider multimodal commute behaviors-as consistent with previous studies. In car-only (Milan GPS traces) and car-heavy (Saudi Arabia) commute datasets, we see that commute time is indeed influenced by commute distance. Finally, we put forth a testable hypothesis and suggest ways for future work to make more accurate and generalizable statements about human commute behaviors.

  4. Brain-computer interface using wavelet transformation and naïve bayes classifier.

    PubMed

    Bassani, Thiago; Nievola, Julio Cesar

    2010-01-01

    The main purpose of this work is to establish an exploratory approach using electroencephalographic (EEG) signal, analyzing the patterns in the time-frequency plane. This work also aims to optimize the EEG signal analysis through the improvement of classifiers and, eventually, of the BCI performance. In this paper a novel exploratory approach for data mining of EEG signal based on continuous wavelet transformation (CWT) and wavelet coherence (WC) statistical analysis is introduced and applied. The CWT allows the representation of time-frequency patterns of the signal's information content by WC qualiatative analysis. Results suggest that the proposed methodology is capable of identifying regions in time-frequency spectrum during the specified task of BCI. Furthermore, an example of a region is identified, and the patterns are classified using a Naïve Bayes Classifier (NBC). This innovative characteristic of the process justifies the feasibility of the proposed approach to other data mining applications. It can open new physiologic researches in this field and on non stationary time series analysis.

  5. Patterns of myopigenic activities with age, gender and ethnicity in Sydney schoolchildren.

    PubMed

    French, Amanda N; Morgan, Ian G; Mitchell, Paul; Rose, Kathryn A

    2013-05-01

    To examine the patterns of myopigenic activity (high near work, low time outdoors) in children growing up in Sydney, Australia, by age, ethnicity and gender. The Sydney Adolescent Vascular and Eye Study (SAVES) re-examined children from the two age cohorts (6 and 12 years at baseline) from the Sydney Myopia Study (SMS). At 5-6 year follow-up, 863 in the younger cohort and 1196 in the older cohort had complete refraction data. Cycloplegic autorefraction (cyclopentolate 1%; Canon RK-F1) was measured at baseline and follow-up. Children who became myopic (≤-0.50 dioptres spherical equivalent refraction) were those classified as non-myopic at baseline and myopic at follow-up. A detailed questionnaire was administered to measure weekly activities, including time spent outdoors and near work at both baseline and follow-up examination. Overall, 128 (14.8%) children in the younger cohort and 210 (17.6%) in the older cohort became myopic. At follow-up, for both cohorts, children had significantly reduced the amount of time spent outdoors (younger cohort, p = 0.001, older cohort, p < 0.0001) and increased near work time (younger cohort, p < 0.0001, older cohort, p = 0.006). Children of East Asian ethnicity spent significantly less time outdoors by more than 7 h per week (both cohorts at baseline and follow-up, all p < 0.0001) and more time in near work activities by close to 3 h compared to European Caucasian children at all ages examined (both cohorts at baseline and follow-up all, p < 0.03). The average pattern of activity for girls differed from that of boys in a similar way (both cohorts at baseline and follow-up all, p < 0.0001). The two independent samples of 12 year-old children provided by follow-up in the younger cohort and baseline in the older cohort gave very similar answers to the questionnaire, with significant differences only evident for computer use (p = 0.001) and books read (p < 0.0001). Answers to the activity questionnaire were very similar in the two cohorts of 12 year-olds, suggesting that the questionnaire gives reproducible answers. However, further work is required for validation. Children's pattern of activities become more myopigenic with age, and differed by gender and by ethnicity at all ages, with girls having a more myopigenic activity pattern than boys, and children of East Asian ancestry having a more myopigenic activity pattern than European Caucasian children. Ophthalmic & Physiological Optics © 2013 The College of Optometrists.

  6. Shift Work, Chronotype, and Melatonin Patterns among Female Hospital Employees on Day and Night Shifts.

    PubMed

    Leung, Michael; Tranmer, Joan; Hung, Eleanor; Korsiak, Jill; Day, Andrew G; Aronson, Kristan J

    2016-05-01

    Shift work-related carcinogenesis is hypothesized to be mediated by melatonin; however, few studies have considered the potential effect modification of this underlying pathway by chronotype or specific aspects of shift work such as the number of consecutive nights in a rotation. In this study, we examined melatonin patterns in relation to shift status, stratified by chronotype and number of consecutive night shifts, and cumulative lifetime exposure to shift work. Melatonin patterns of 261 female personnel (147 fixed-day and 114 on rotations, including nights) at Kingston General Hospital were analyzed using cosinor analysis. Urine samples were collected from all voids over a 48-hour specimen collection period for measurement of 6-sulfatoxymelatonin concentrations using the Buhlmann ELISA Kit. Chronotypes were assessed using mid-sleep time (MSF) derived from the Munich Chronotype Questionnaire (MCTQ). Sociodemographic, health, and occupational information were collected by questionnaire. Rotational shift nurses working nights had a lower mesor and an earlier time of peak melatonin production compared to day-only workers. More pronounced differences in mesor and acrophase were seen among later chronotypes, and shift workers working ≥3 consecutive nights. Among nurses, cumulative shift work was associated with a reduction in mesor. These results suggest that evening-types and/or shift workers working ≥3 consecutive nights are more susceptible to adverse light-at-night effects, whereas long-term shift work may also chronically reduce melatonin levels. Cumulative and current exposure to shift work, including nights, affects level and timing of melatonin production, which may be related to carcinogenesis and cancer risk. Cancer Epidemiol Biomarkers Prev; 25(5); 830-8. ©2016 AACR. ©2016 American Association for Cancer Research.

  7. Supply and demand mismatch for flexible (part-time) surgical training in Australasia.

    PubMed

    McDonald, Rachel E; Jeeves, Amy E; Vasey, Carolyn E; Wright, Deborah M; O'Grady, Gregory

    2013-05-06

    To define current patterns of flexible (part-time) surgical training in Australasia, determine supply and demand for part-time positions, and identify work-related factors motivating interest in flexible training. All Royal Australasian College of Surgeons trainees (n = 1191) were surveyed in 2010. Questions assessed demographic characteristics and working patterns, interest in flexible training, work-related fatigue and work-life balance preferences. Interest in part-time training, and work-related factors motivating this interest. Of the 1191 trainees, 659 responded (response rate, 55.3%). Respondents were representative of all trainees in terms of specialty and sex. The median age of respondents was 32 2013s, and 187 (28.4%) were female. Most of the 659 respondents (627, 95.1%) were in full-time clinical training; only two (0.3%) were in part-time clinical training, and 30 (4.6%) were not in active clinical training. An interest in part-time training was reported by 208 respondents (31.6%; 54.3% of women v 25.9% of men; P < 0.001). Trainees expressing an interest in part-time training were more likely to report that fatigue impaired their performance at work and limited their social or family life, and that they had insufficient time in life for things outside surgical training, including study or research (P < 0.05). There is a striking mismatch between demand for flexible surgical training and the number of trainees currently in part-time training positions in Australia and New Zealand. Efforts are needed to facilitate part-time surgical training.

  8. Temporal patterns of sitting at work are associated with neck-shoulder pain in blue-collar workers: a cross-sectional analysis of accelerometer data in the DPHACTO study.

    PubMed

    Hallman, David M; Mathiassen, Svend Erik; Heiden, Marina; Gupta, Nidhi; Jørgensen, Marie Birk; Holtermann, Andreas

    2016-07-01

    Our aim was to examine the extent to which temporal patterns of sitting during occupational work and during leisure-time, assessed using accelerometry, are associated with intense neck-shoulder pain (NSP) in blue-collar workers. The population consisted of 659 Danish blue-collar workers. Accelerometers were attached to the thigh, hip, trunk and upper dominant arm to measure sitting time and physical activity across four consecutive days. Temporal sitting patterns were expressed separately for work and leisure by the proportion of total time spent sitting in brief bursts (0-5 min), moderate (>5-20 min) and prolonged (>20 min) periods. The peak NSP intensity during the previous 3 months was assessed using a numerical rating scale (range 0-10) and dichotomized into a lower (≤4) and higher (>4) NSP score. Logistic regression analyses with multiple adjustments for individual and occupational factors were performed to determine the association between brief, moderate and prolonged sitting periods, and NSP intensity. Time in brief bursts of occupational sitting was negatively associated with NSP intensity (adjusted OR 0.68, 95 % CI 0.48-0.98), while time in moderate periods of occupational sitting showed a positive association with NSP (adjusted OR 1.32, 95 % CI 1.04-1.69). Time in prolonged periods of occupational sitting was not associated with NSP (adjusted OR 0.78, 95 % CI 0.78-1.09). We found no significant association between brief, moderate or prolonged sitting periods during leisure, and NSP. Our findings indicate that the association between occupational sitting time and intense NSP among blue-collar workers is sensitive to the temporal pattern of sitting.

  9. Work-leave rotation pattern and incidence of offshore workplace injury.

    PubMed

    Massey, S

    2018-05-17

    Studies on work-leave rotation pattern and work place injuries among offshore oil and gas workers have been few and limited to a 2- or 3-week rotation schedule. To examine incidence of workplace injury in relation to the duration of time into work rotation for extended work schedules up to 24 weeks. Six-year injury data on four offshore installations were extracted. Data were analysed for incidence of injury over time and relative risk using linear trend lines and regression. In total, 311 injuries for 1302 workers were analysed, 39% with rotation schedule of 4 weeks work and 4 weeks rest, 27% 8 weeks work and 4 weeks rest, 23% 16 weeks work and 4 weeks rest and 10% 24 weeks work and 4 weeks rest. Incidence of injury decreased as duration of time into the work rotation increased, corrected for exposure, and this was statistically significant for all rotations in first 4 weeks (P < 0.01). Negative correlation between time offshore and injury was observed in all schedules and consistent for age groups, categories of work, shifts and severity of injury. There was no difference in relative risk of injuries between the four schedules, when corrected for exposure and occupational risk of injury. These results are at variance with previous studies, although no prior study has looked beyond 3-week rotation schedule. Longer offshore schedules are safely possible and this could help decrease manpower and logistics costs for oil and gas companies coping with unprecedented low oil prices.

  10. Principal Component Analysis in the Spectral Analysis of the Dynamic Laser Speckle Patterns

    NASA Astrophysics Data System (ADS)

    Ribeiro, K. M.; Braga, R. A., Jr.; Horgan, G. W.; Ferreira, D. D.; Safadi, T.

    2014-02-01

    Dynamic laser speckle is a phenomenon that interprets an optical patterns formed by illuminating a surface under changes with coherent light. Therefore, the dynamic change of the speckle patterns caused by biological material is known as biospeckle. Usually, these patterns of optical interference evolving in time are analyzed by graphical or numerical methods, and the analysis in frequency domain has also been an option, however involving large computational requirements which demands new approaches to filter the images in time. Principal component analysis (PCA) works with the statistical decorrelation of data and it can be used as a data filtering. In this context, the present work evaluated the PCA technique to filter in time the data from the biospeckle images aiming the reduction of time computer consuming and improving the robustness of the filtering. It was used 64 images of biospeckle in time observed in a maize seed. The images were arranged in a data matrix and statistically uncorrelated by PCA technique, and the reconstructed signals were analyzed using the routine graphical and numerical methods to analyze the biospeckle. Results showed the potential of the PCA tool in filtering the dynamic laser speckle data, with the definition of markers of principal components related to the biological phenomena and with the advantage of fast computational processing.

  11. Electrical Field Guided Electrospray Deposition for Production of Gradient Particle Patterns.

    PubMed

    Yan, Wei-Cheng; Xie, Jingwei; Wang, Chi-Hwa

    2018-06-06

    Our previous work demonstrated the uniform particle pattern formation on the substrates using electrical field guided electrospray deposition. In this work, we reported for the first time the fabrication of gradient particle patterns on glass slides using an additional point, line, or bar electrode based on our previous electrospray deposition configuration. We also demonstrated that the polydimethylsiloxane (PDMS) coating could result in the formation of uniform particle patterns instead of gradient particle patterns on glass slides using the same experimental setup. Meanwhile, we investigated the effect of experimental configurations on the gradient particle pattern formation by computational simulation. The simulation results are in line with experimental observations. The formation of gradient particle patterns was ascribed to the gradient of electric field and the corresponding focusing effect. Cell patterns can be formed on the particle patterns deposited on PDMS-coated glass slides. The formed particle patterns hold great promise for high-throughput screening of biomaterial-cell interactions and sensing.

  12. The impact of long work hours and shift work on cognitive errors in nurses.

    PubMed

    Rhéaume, Ann; Mullen, Jane

    2018-01-01

    Pilot study to examine the impact of long work hours and shift work on cognitive errors in nurses. Twelve-hour shifts are more commonly used in hospital settings and there is growing concern over the impact that extended and irregular work hours have on nurses' well-being and performance. Twenty-eight nurses working different shifts (8-hr days and 12-hr rotation) participated in this study. Nurses were assessed at the beginning of four consecutive shifts using actigraphy, a sleep diary and an after work questionnaire. Nurses working 12-hr rotations had less total sleep time and less sleep efficiency than 8-hr day nurses. Twelve-hour rotation nurses also napped more than their counterparts. There were no differences between the two groups with respect to cognitive errors. Twelve-hour rotations have a negative effect on nurses' sleep patterns. There is no evidence indicating 12-hr rotations increased errors. Nurse managers can implement specific strategies, such as greater shift work flexibility and designated quiet time, to reduce the effects of disturbed sleep patterns in nurses. © 2017 John Wiley & Sons Ltd.

  13. Leisure Patterns among Four-Day Workers.

    ERIC Educational Resources Information Center

    Seltzer, Joseph; Wilson, James A.

    1980-01-01

    Insight into the patterns of leisure time usage may lead to a better understanding of the relationships between work and leisure and other aspects of an individual's life. A five-factor model was developed to explicate individual motivations for leisure pursuits. (JN)

  14. New Patterns for Working Time; International Conference. (Paris, September 26-29, 1972). Final Report.

    ERIC Educational Resources Information Center

    Organisation for Economic Cooperation and Development, Paris (France).

    The conference was arranged by the Organization for Economic Cooperation and Development (OECD) Manpower and Social Affairs Directorate to enable representatives of employers' associations, labor unions, senior civil servants and academics from member OECD countries to exchange views on more flexible arrangements of working time. The document…

  15. Associations of long-term shift work with waking salivary cortisol concentration and patterns among police officers.

    PubMed

    Fekedulegn, Desta; Burchfiel, Cecil M; Violanti, John M; Hartley, Tara A; Charles, Luenda E; Andrew, Michael E; Miller, Diane B

    2012-01-01

    The objective of this study was to evaluate whether long-term shift work is associated with both the total hormonal secretion after awakening and the pattern of the cortisol levels during the first hour following awakening, among 65 randomly selected police officers who represent a high stress occupation. Dominant shift (Day, Afternoon, or Midnight) was ascertained using daily payroll records of each participant's work activities during the 6-8 yrs prior to saliva sampling. Four salivary samples were collected at 15 min intervals upon first awakening. After accounting for potential confounders, salivary cortisol concentrations averaged across all four time points and total area under the curve differed significantly across shift with midnight shift workers showing suppressed awakening cortisol response relative to the afternoon and day shift. The percent of hours worked on midnight shift was inversely correlated with total awakening cortisol output. In contrast, the pattern of cortisol secretion during the first hour following waking appeared not to be affected as no significant interaction effect was found between time since awakening and shift work. The results show that long-term midnight shift work is associated with decreased absolute mean level and total volume of cortisol released over the waking period.

  16. Associations of Long-term Shift Work with Waking Salivary Cortisol Concentration and Patterns among Police Officers

    PubMed Central

    FEKEDULEGN, Desta; BURCHFIEL, Cecil M.; VIOLANTI, John M.; HARTLEY, Tara A.; CHARLES, Luenda E.; ANDREW, Michael E.; MILLER, Diane B.

    2015-01-01

    The objective of this study was to evaluate whether long-term shift work is associated with both the total hormonal secretion after awakening and the pattern of the cortisol levels during the first hour following awakening, among 65 randomly selected police officers who represent a high stress occupation. Dominant shift (Day, Afternoon, or Midnight) was ascertained using daily payroll records of each participant’s work activities during the 6–8 yrs prior to saliva sampling. Four salivary samples were collected at 15 min intervals upon first awakening. After accounting for potential confounders, salivary cortisol concentrations averaged across all four time points and total area under the curve differed significantly across shift with midnight shift workers showing suppressed awakening cortisol response relative to the afternoon and day shift. The percent of hours worked on midnight shift was inversely correlated with total awakening cortisol output. In contrast, the pattern of cortisol secretion during the first hour following waking appeared not to be affected as no significant interaction effect was found between time since awakening and shift work. The results show that long-term midnight shift work is associated with decreased absolute mean level and total volume of cortisol released over the waking period. PMID:23047078

  17. Patterns of work-related intimate partner violence and job performance among abusive men.

    PubMed

    Mankowski, Eric S; Galvez, Gino; Perrin, Nancy A; Hanson, Ginger C; Glass, Nancy

    2013-10-01

    This study assesses different types of work-related intimate partner violence (IPV) perpetration and their relationship to perpetrators' work performance and employment. We determine if groups of abusive men with similar patterns of work-related IPV exist and then examine whether the patterns are related to their characteristics, job performance, and employment outcomes. Participants were 198 adult men (60% Latino, 40% non-Latino) from batterer intervention programs (BIPs) who self-reported their lifetime work-related IPV and job outcomes. Five distinct clusters were identified and named based on the pattern (predominance or absence) of different work-related abusive behaviors reported: (a) low-level tactics, (b) job interference, (c) job interference with threatened or actual violence, (d) extreme abuse without jealousy and (e) extreme abuse. Analyses revealed significant differences between the clusters on ethnicity, parental status, partner's employment status, income, education, and (among Latinos only) acculturation. The probability of men's work-related IPV substantially impacting their own job performance was nearly 4 times greater among those in the extreme abuse cluster than those in the low-level tactics cluster. These data inform the development of employee training programs and workplace policies for reducing IPV that affects the workplace.

  18. The influence of daily sleep patterns of commercial truck drivers on driving performance

    PubMed Central

    Chen, Guang Xiang; Fang, Youjia; Guo, Feng; Hanowski, Richard J.

    2016-01-01

    Fatigued and drowsy driving has been found to be a major cause of truck crashes. Lack of sleep is the number one cause of fatigue and drowsiness. However, there are limited data on the sleep patterns (sleep duration, sleep percentage in the duration of non-work period, and the time when sleep occurred) of truck drivers in non-work periods and the impact on driving performance. This paper examined sleep patterns of 96 commercial truck drivers during non-work periods and evaluated the influence these sleep patterns had on truck driving performance. Data were from the Naturalistic Truck Driving Study. Each driver participated in the study for approximately four weeks. A shift was defined as a non-work period followed by a work period. A total of 1397 shifts were identified. Four distinct sleep patterns were identified based on sleep duration, sleep start/end point in a non-work period, and the percentage of sleep with reference to the duration of non-work period. Driving performance was measured by safety-critical events, which included crashes, near-crashes, crash-relevant conflicts, and unintentional lane deviations. Negative binomial regression was used to evaluate the association between the sleep patterns and driving performance, adjusted for driver demographic information. The results showed that the sleep pattern with the highest safety-critical event rate was associated with shorter sleep, sleep in the early stage of a non-work period, and less sleep between 1 a.m. and 5 a.m. This study also found that male drivers, with fewer years of commercial vehicle driving experience and higher body mass index, were associated with deteriorated driving performance and increased driving risk. The results of this study could inform hours-of-service policy-making and benefit safety management in the trucking industry. PMID:26954762

  19. Overworked Individuals or Overworked Families? Explaining Trends in Work, Leisure, and Family Time.

    ERIC Educational Resources Information Center

    Jacobs, Jerry A.; Gerson, Kathleen

    2001-01-01

    Data from the 1970 and 1997 Current Population Survey demonstrate that, more than changes in working hours, the shift from male-breadwinner to dual-earner and single-parent households has increased concern for family-work balance. Research should focus on combined work schedules of family members rather than changes in individual work patterns.…

  20. Working hours as a risk factor in the development of musculoskeletal complaints.

    PubMed

    Waersted, M; Westgaard, R H

    1991-03-01

    The length of daily working hours as a risk factor for the development of musculoskeletal complaints was studied by comparing the sick leave statistics of 408 sewing machine operators on full-time schedules (8 h working day) with 210 operators on part-time schedules (5 h working day). Working part-time was shown to postpone the occurrence of sick leave due to musculoskeletal disorders by approximately half a year. There was no lasting effect on the reduction in working hours on sick leave due to shoulder-neck complaints, but a reduction in low back complaints was indicated. It is suggested that any reorganization of work activities to counteract musculoskeletal injuries from repetitive work should aim to break up the muscular activity patterns over time periods considerably shorter than the 5 h working day of the part-time workers in the present study.

  1. Some Sociological Alternatives to Human Capital Theory and Their Implications for Research on Post-Compulsory Education and Training. Patterns of Participation in Adult Education and Training. Working Paper 3.

    ERIC Educational Resources Information Center

    Fevre, Ralph

    This working paper is a product of a regional study in industrial South Wales of the determinants of participation and non-participation in post-compulsory education and training, with special reference to processes of change in the patterns of these determinants over time and to variations between geographical areas. Based on this data, three…

  2. Practice Patterns and Job Satisfaction of Mohs Surgeons.

    PubMed

    Kohli, Nita; Golda, Nicholas

    2018-01-01

    There is a paucity of data on Mohs surgery workforce patterns. To identify if gender differences exist in practice patterns of Mohs surgeons, factors that influence these differences, and factors influencing job satisfaction among Mohs surgeons. An electronic survey was distributed to dermatology organizations targeting members of the American College of Mohs Surgery (ACMS), from October 2015 to April 2016. Two hundred twenty-seven ACMS members responded; 37% were women. Twenty-five percent of women and 19% of men work part time. Thirty-seven percent of women practice in academia versus 22% of men. Forty-three percent of women and 23% of men identified children as a factor affecting their ability to work full time. Gender comparisons for current job satisfaction show 57% of men and 35% of women being very satisfied. Supervision/feedback/recognition adds to satisfaction at a higher rate for women (53%) than for men (29%). For both genders combined, work content, patient base, and autonomy had the highest average job satisfaction ratings. Gender differences exist in practice patterns and job satisfaction of Mohs surgeons. This study demonstrates factors that could influence job satisfaction among female Mohs surgeons-knowledge that is important to individuals who lead, mentor, or supervise female Mohs surgeons.

  3. Clocking in: The Organization of Work Time and Health in the United States

    ERIC Educational Resources Information Center

    Kleiner, Sibyl; Pavalko, Eliza K.

    2010-01-01

    This article assesses the health implications of emerging patterns in the organization of work time. Using data from the National Longitudinal Survey of Youth 1979, we examine general mental and physical health (SF-12 scores), psychological distress (CESD score), clinical levels of obesity, and the presence of medical conditions, at age 40.…

  4. Working under daylight intensity lamp: an occupational risk for developing circadian rhythm sleep disorder?

    PubMed

    Doljansky, J T; Kannety, H; Dagan, Y

    2005-01-01

    A 47-yr-old male was admitted to the Institute for Fatigue and Sleep Medicine complaining of severe fatigue and daytime sleepiness. His medical history included diagnosis of depression and chronic fatigue syndrome. Antidepressant drugs failed to improve his condition. He described a gradual evolvement of an irregular sleep-wake pattern within the past 20 yrs, causing marked distress and severe impairment of daily functioning. He had to change to a part-time position 7 yrs ago, because he was unable to maintain a regular full-time job schedule. A 10-day actigraphic record revealed an irregular sleep-wake pattern with extensive day-to-day variability in sleep onset time and sleep duration, and a 36 h sampling of both melatonin level and oral temperature (12 samples, once every 3 h) showed abnormal patterns, with the melatonin peak around noon and oral temperature peak around dawn. Thus, the patient was diagnosed as suffering from irregular sleep-wake pattern. Treatment with melatonin (5 mg, 2 h before bedtime) did not improve his condition. A further investigation of the patient's daily habits and environmental conditions revealed two important facts. First, his occupation required work under a daylight intensity lamp (professional diamond-grading equipment of more than 8000 lux), and second, since the patient tended to work late, the exposure to bright light occurred mostly at night. To recover his circadian rhythmicity and stabilize his sleep-wake pattern, we recommended combined treatment consisting of evening melatonin ingestion combined with morning (09:00 h) bright light therapy (0800 lux for 1 h) plus the avoidance of bright light in the evening. Another 10-day actigraphic study done only 1 wk after initiating the combined treatment protocol revealed stabilization of the sleep-wake pattern with advancement of sleep phase. In addition, the patient reported profound improvement in maintaining wakefulness during the day. This case study shows that chronic exposure to bright light at the wrong biological time, during the nighttime, may have serious effects on the circadian sleep-wake patterns and circadian time structure. Therefore, night bright light exposure must be considered to be a risk factor of previously unrecognized occupational diseases of altered circadian time structure manifested as irregularity of the 24 h sleep-wake cycle and melancholy.

  5. Cooperation, competition and goal interdependence in work teams: a multilevel approach.

    PubMed

    Aritzeta, Aitor; Balluerka, Nekane

    2006-11-01

    The aim of this research was to predict cooperative and competitive conflict management styles in 26 new start-up work teams (time 1), and after one year of functioning (time 2) in an automotive company. Vertical-horizontal, individualism-collectivism cultural patterns were used as predictive variables. It was predicted that goal interdependence would moderate the relationship between cultural patterns and conflict management styles. Because of the hierarchically nested data structure, a Multilevel Analysis approach was used. Horizontal and vertical collectivism increased cooperation, and horizontal and vertical individualism increased competition. Only when work teams had been functioning for a year, goal interdependence increased cooperation and interaction effects between goal interdependence and vertical types of individualism and collectivism were observed. Implications for team-building as organizational transformational strategies are discussed.

  6. Psychological detachment from work during non-work time: linear or curvilinear relations with mental health and work engagement?

    PubMed

    Shimazu, Akihito; Matsudaira, Ko; Jonge, Jan DE; Tosaka, Naoya; Watanabe, Kazuhiro; Takahashi, Masaya

    2016-06-10

    This study examined whether a higher level of psychological detachment during non-work time is associated with better employee mental health (Hypothesis 1), and examined whether psychological detachment has a curvilinear relation (inverted U-shaped pattern) with work engagement (Hypothesis 2). A large cross-sectional Internet survey was conducted among registered monitors of an Internet survey company in Japan. The questionnaire included scales for psychological detachment, employee mental health, and work engagement as well as for job characteristics and demographic variables as potential confounders. The hypothesized model was tested with moderated structural equation modeling techniques among 2,234 respondents working in the tertiary industries with regular employment. Results showed that psychological detachment had curvilinear relations with mental health as well as with work engagement. Mental health improved when psychological detachment increased from a low to higher levels but did not benefit any further from extremely high levels of psychological detachment. Work engagement showed the highest level at an intermediate level of detachment (inverted U-shaped pattern). Although high psychological detachment may enhance employee mental health, moderate levels of psychological detachment are most beneficial for his or her work engagement.

  7. Psychological detachment from work during non-work time: linear or curvilinear relations with mental health and work engagement?

    PubMed Central

    SHIMAZU, Akihito; MATSUDAIRA, Ko; DE JONGE, Jan; TOSAKA, Naoya; WATANABE, Kazuhiro; TAKAHASHI, Masaya

    2016-01-01

    This study examined whether a higher level of psychological detachment during non-work time is associated with better employee mental health (Hypothesis 1), and examined whether psychological detachment has a curvilinear relation (inverted U-shaped pattern) with work engagement (Hypothesis 2). A large cross-sectional Internet survey was conducted among registered monitors of an Internet survey company in Japan. The questionnaire included scales for psychological detachment, employee mental health, and work engagement as well as for job characteristics and demographic variables as potential confounders. The hypothesized model was tested with moderated structural equation modeling techniques among 2,234 respondents working in the tertiary industries with regular employment. Results showed that psychological detachment had curvilinear relations with mental health as well as with work engagement. Mental health improved when psychological detachment increased from a low to higher levels but did not benefit any further from extremely high levels of psychological detachment. Work engagement showed the highest level at an intermediate level of detachment (inverted U-shaped pattern). Although high psychological detachment may enhance employee mental health, moderate levels of psychological detachment are most beneficial for his or her work engagement. PMID:26829972

  8. Learning and the Part-Time Worker.

    ERIC Educational Resources Information Center

    Tisdall, Caroline

    1999-01-01

    Part-time workers, who are primarily female, are not well served by staff development and training models that reflect values and assumptions of traditional working patterns. Part-timers face such training barriers as management attitudes, lack of time and resources, and inflexibility. (SK)

  9. Sleep patterns, work, and strain among young students in hospitality and tourism.

    PubMed

    Brand, Serge; Hermann, Bernadette; Muheim, Flavio; Beck, Johannes; Holsboer-Trachsler, Edith

    2008-07-01

    Good and sufficient sleep is crucial for a good quality of life. We investigated the associations between sleep patterns, work, and strain among students of hospitality and tourism. 92 students completed psychological and sleep-related questionnaires, and a sleep/work log for one week. Sleeping hours were inversely correlated with working hours. Decreased sleep quality was associated with increased scores of strain, depression and anxiety. Participants with increased working hours were 3.2 times more likely to report heightened insomnia scores than those with lower weekly working hours. Working on weekends was associated with increased strain with family life and peers. In hospitality and tourism, the employees' 'personal costs' for a 24/7 service may be underestimated; unfavourable work schedules are linked with decreased sleep quality, symptoms of depression, anxiety, and with social problems.

  10. Time for Children: Trends in the Employment Patterns of Parents, 1967-2009. NBER Working Paper No. 17135

    ERIC Educational Resources Information Center

    Fox, Liana E.; Han, Wen-Jui; Ruhm, Christopher; Waldfogel, Jane

    2011-01-01

    Utilizing data from the 1967-2009 years of the March Current Population Surveys, we examine two important resources for children's well-being: time and money. We document trends in parental employment, from the perspective of children, and show what underlies these trends. We find that increases in family work hours mainly reflect movements into…

  11. Managing Time and Tasks.

    ERIC Educational Resources Information Center

    Handy, Alice Evans; Yucht, Alice H.

    1993-01-01

    Includes two articles that discuss time management and mail management strategies for librarians. Highlights include identifying personal work styles; planning and prioritizing; using calendars and computers; reexamining traffic patterns; delegating; and sorting and handling mail. (Contains eight references.) (LRW)

  12. The interplay between women's life course work patterns and financial planning for later life.

    PubMed

    Berger, Ellie D; Denton, Margaret A

    2004-01-01

    In order to gain a comprehensive understanding of the interplay between women's life course work patterns and their financial planning for later life, we examined data from semi-structured interviews with retired women (n = 28) aged 59 to 92. The majority of women disrupted their careers at some point in time, for an average of 14 years, primarily for child-rearing responsibilities. We found that financial preparedness and income security in later life are structured by women's life course work patterns. However, individuals also have the ability to shape their own lives and many of the women took the initiative to acquire financial knowledge irrespective of their work situation. Financial-planning advice that participants gave to future generations of older women was also explored and centred on the importance of saving, avoiding debt, maintaining financial independence, and planning ahead.

  13. Intra-individual variability in day-to-day and month-to-month measurements of physical activity and sedentary behaviour at work and in leisure-time among Danish adults.

    PubMed

    Pedersen, E S L; Danquah, I H; Petersen, C B; Tolstrup, J S

    2016-12-03

    Accelerometers can obtain precise measurements of movements during the day. However, the individual activity pattern varies from day-to-day and there is limited evidence on measurement days needed to obtain sufficient reliability. The aim of this study was to examine variability in accelerometer derived data on sedentary behaviour and physical activity at work and in leisure-time during week days among Danish office employees. We included control participants (n = 135) from the Take a Stand! Intervention; a cluster randomized controlled trial conducted in 19 offices. Sitting time and physical activity were measured using an ActiGraph GT3X+ fixed on the thigh and data were processed using Acti4 software. Variability was examined for sitting time, standing time, steps and time spent in moderate-to-vigorous physical activity (MVPA) per day by multilevel mixed linear regression modelling. Results of this study showed that the number of days needed to obtain a reliability of 80% when measuring sitting time was 4.7 days for work and 5.5 days for leisure time. For physical activity at work, 4.0 days and 4.2 days were required to measure steps and MVPA, respectively. During leisure time, more monitoring time was needed to reliably estimate physical activity (6.8 days for steps and 5.8 days for MVPA). The number of measurement days needed to reliably estimate activity patterns was greater for leisure time than for work time. The domain specific variability is of great importance to researchers and health promotion workers planning to use objective measures of sedentary behaviour and physical activity. Clinical trials NCT01996176 .

  14. Turbulent Superstructures in Rayleigh-Bénard convection at different Prandtl number

    NASA Astrophysics Data System (ADS)

    Schumacher, Jörg; Pandey, Ambrish; Ender, Martin; Westermann, Rüdiger; Scheel, Janet D.

    2017-11-01

    Large-scale patterns of the temperature and velocity field in horizontally extended cells can be considered as turbulent superstructures in Rayleigh-Bénard convection (RBC). These structures are obtained once the turbulent fluctuations are removed by a finite-time average. Their existence has been reported for example in Bailon-Cuba et al.. This large-scale order obeys a strong similarity with the well-studied patterns from the weakly nonlinear regime at lower Rayleigh number in RBC. In the present work we analyze the superstructures of RBC at different Prandtl number for Prandtl values between Pr = 0.005 for liquid sodium and 7 for water. The characteristic evolution time scales, the typical spatial extension of the rolls and the properties of the defects of the resulting superstructure patterns are analyzed. Data are obtained from well-resolved spectral element direct numerical simulations. The work is supported by the Priority Programme SPP 1881 of the Deutsche Forschungsgemeinschaft.

  15. Using missing ordinal patterns to detect nonlinearity in time series data.

    PubMed

    Kulp, Christopher W; Zunino, Luciano; Osborne, Thomas; Zawadzki, Brianna

    2017-08-01

    The number of missing ordinal patterns (NMP) is the number of ordinal patterns that do not appear in a series after it has been symbolized using the Bandt and Pompe methodology. In this paper, the NMP is demonstrated as a test for nonlinearity using a surrogate framework in order to see if the NMP for a series is statistically different from the NMP of iterative amplitude adjusted Fourier transform (IAAFT) surrogates. It is found that the NMP works well as a test statistic for nonlinearity, even in the cases of very short time series. Both model and experimental time series are used to demonstrate the efficacy of the NMP as a test for nonlinearity.

  16. Impact of SCBA size and fatigue from different firefighting work cycles on firefighter gait.

    PubMed

    Kesler, Richard M; Bradley, Faith F; Deetjen, Grace S; Angelini, Michael J; Petrucci, Matthew N; Rosengren, Karl S; Horn, Gavin P; Hsiao-Wecksler, Elizabeth T

    2018-04-04

    Risk of slips, trips and falls in firefighters maybe influenced by the firefighter's equipment and duration of firefighting. This study examined the impact of a four self-contained breathing apparatus (SCBA) three SCBA of increasing size and a prototype design and three work cycles one bout (1B), two bouts with a five-minute break (2B) and two bouts back-to-back (BB) on gait in 30 firefighters. Five gait parameters (double support time, single support time, stride length, step width and stride velocity) were examined pre- and post-firefighting activity. The two largest SCBA resulted in longer double support times relative to the smallest SCBA. Multiple bouts of firefighting activity resulted in increased single and double support time and decreased stride length, step width and stride velocity. These results suggest that with larger SCBA or longer durations of activity, firefighters may adopt more conservative gait patterns to minimise fall risk. Practitioner Summary: The effects of four self-contained breathing apparatus (SCBA) and three work cycles on five gait parameters were examined pre- and post-firefighting activity. Both SCBA size and work cycle affected gait. The two largest SCBA resulted in longer double support times. Multiple bouts of activity resulted in more conservative gait patterns.

  17. Distinct longitudinal patterns of absenteeism and their antecedents in full-time Australian employees.

    PubMed

    Magee, Christopher A; Caputi, Peter; Lee, Jeong Kyu

    2016-01-01

    This paper investigated distinct longitudinal trajectories of absenteeism over time, and underlying demographic, work, and health antecedents. Data from the Household, Income, and Labor Dynamics in Australia Survey were used; this is a panel study of a representative sample of Australian households. This paper focused on 2,481 full-time employees across a 5-year period. Information on annual sick leave and relevant sociodemographic, work, and health-related factors was collected through interviews and self-completed surveys. Growth mixture modeling indicated 4 distinct longitudinal patterns of absenteeism over time. The moderate absenteeism trajectory (34.8%) of the sample had 4-5 days of sick leave per year and was used as the reference group. The low absenteeism trajectory (33.5%) had 1-2 days of absenteeism per year, while the no absenteeism trajectory (23.6%) had very low rates of absenteeism (<1 day per year). Finally, a smaller trajectory accounting for 8.1% of the sample had high levels of absenteeism (>11 days per year). Compared with the moderate absenteeism trajectory, the high absenteeism trajectory was characterized by poor health; the no absenteeism and low absenteeism trajectories had better health but may also reflect processes relating to presenteeism. These results provide important insights into the nature of absenteeism in Australian employees, and suggest that different patterns of absenteeism over time could reflect a range of demographic, work, and health related factors. (c) 2016 APA, all rights reserved).

  18. Masticatory motor patterns in ungulates: a quantitative assessment of jaw-muscle coordination in goats, alpacas and horses.

    PubMed

    Williams, Susan H; Vinyard, Christopher J; Wall, Christine E; Hylander, William L

    2007-04-01

    We investigated patterns of jaw-muscle coordination during rhythmic mastication in three species of ungulates displaying the marked transverse jaw movements typical of many large mammalian herbivores. In order to quantify consistent motor patterns during chewing, electromyograms were recorded from the superficial masseter, deep masseter, posterior temporalis and medial pterygoid muscles of goats, alpacas and horses. Timing differences between muscle pairs were evaluated in the context of an evolutionary model of jaw-muscle function. In this model, the closing and food reduction phases of mastication are primarily controlled by two distinct muscle groups, triplet I (balancing-side superficial masseter and medial pterygoid and working-side posterior temporalis) and triplet II (working-side superficial masseter and medial pterygoid and balancing-side posterior temporalis), and the asynchronous activity of the working- and balancing-side deep masseters. The three species differ in the extent to which the jaw muscles are coordinated as triplet I and triplet II. Alpacas, and to a lesser extent, goats, exhibit the triplet pattern whereas horses do not. In contrast, all three species show marked asynchrony of the working-side and balancing-side deep masseters, with jaw closing initiated by the working-side muscle and the balancing-side muscle firing much later during closing. However, goats differ from alpacas and horses in the timing of the balancing-side deep masseter relative to the triplet II muscles. This study highlights interspecific differences in the coordination of jaw muscles to influence transverse jaw movements and the production of bite force in herbivorous ungulates.

  19. The influence of daily sleep patterns of commercial truck drivers on driving performance.

    PubMed

    Chen, Guang Xiang; Fang, Youjia; Guo, Feng; Hanowski, Richard J

    2016-06-01

    Fatigued and drowsy driving has been found to be a major cause of truck crashes. Lack of sleep is the number one cause of fatigue and drowsiness. However, there are limited data on the sleep patterns (sleep duration, sleep percentage in the duration of non-work period, and the time when sleep occurred) of truck drivers in non-work periods and the impact on driving performance. This paper examined sleep patterns of 96 commercial truck drivers during non-work periods and evaluated the influence these sleep patterns had on truck driving performance. Data were from the Naturalistic Truck Driving Study. Each driver participated in the study for approximately four weeks. A shift was defined as a non-work period followed by a work period. A total of 1397 shifts were identified. Four distinct sleep patterns were identified based on sleep duration, sleep start/end point in a non-work period, and the percentage of sleep with reference to the duration of non-work period. Driving performance was measured by safety-critical events, which included crashes, near-crashes, crash-relevant conflicts, and unintentional lane deviations. Negative binomial regression was used to evaluate the association between the sleep patterns and driving performance, adjusted for driver demographic information. The results showed that the sleep pattern with the highest safety-critical event rate was associated with shorter sleep, sleep in the early stage of a non-work period, and less sleep between 1 a.m. and 5 a.m. This study also found that male drivers, with fewer years of commercial vehicle driving experience and higher body mass index, were associated with deteriorated driving performance and increased driving risk. The results of this study could inform hours-of-service policy-making and benefit safety management in the trucking industry. Published by Elsevier Ltd.

  20. Occupational Injuries in a Commune in Rural Vietnam Transitioning From Agriculture to New Industries

    PubMed Central

    Leamon, Tom B.; Willetts, Joanna L.; Binh, Ta Thi Tuyet; Diep, Nguyen Bich; Wegman, David H.; Kriebel, David

    2011-01-01

    Objectives. We explored the impact on work-related injuries of workers splitting time between industry and agriculture, a common situation in developing countries. Methods. In 2005, we administered a cross-sectional survey to 2615 households of Xuan Tien, a developing rural community of Vietnam, regarding self-reported injuries and hours worked for 1 year. We defined groups as working in industry, agriculture, or a mix of both. Results. Overlapping employment (part time in agriculture and up to full time in industry) increased the risk of injury in both agricultural and industrial work. This pattern held across all work groups defined by the relative amount of time worked in agriculture. Those working fewer than 500 hours annually in agriculture had an agricultural injury rate (872 per 1000 full-time equivalents) that was more than 4 times higher than the average rate overall (203 per 1000) and the rate for workers employed only in industry (178 per 1000). Conclusions. Working in agriculture for short durations while working in industry increased the risk of injury substantially in both types of work. PMID:21490336

  1. Occupational injuries in a commune in rural Vietnam transitioning from agriculture to new industries.

    PubMed

    Marucci-Wellman, Helen; Leamon, Tom B; Willetts, Joanna L; Binh, Ta Thi Tuyet; Diep, Nguyen Bich; Wegman, David H; Kriebel, David

    2011-05-01

    We explored the impact on work-related injuries of workers splitting time between industry and agriculture, a common situation in developing countries. In 2005, we administered a cross-sectional survey to 2615 households of Xuan Tien, a developing rural community of Vietnam, regarding self-reported injuries and hours worked for 1 year. We defined groups as working in industry, agriculture, or a mix of both. Overlapping employment (part time in agriculture and up to full time in industry) increased the risk of injury in both agricultural and industrial work. This pattern held across all work groups defined by the relative amount of time worked in agriculture. Those working fewer than 500 hours annually in agriculture had an agricultural injury rate (872 per 1000 full-time equivalents) that was more than 4 times higher than the average rate overall (203 per 1000) and the rate for workers employed only in industry (178 per 1000). Working in agriculture for short durations while working in industry increased the risk of injury substantially in both types of work.

  2. Choosing the Most Effective Pattern Classification Model under Learning-Time Constraint.

    PubMed

    Saito, Priscila T M; Nakamura, Rodrigo Y M; Amorim, Willian P; Papa, João P; de Rezende, Pedro J; Falcão, Alexandre X

    2015-01-01

    Nowadays, large datasets are common and demand faster and more effective pattern analysis techniques. However, methodologies to compare classifiers usually do not take into account the learning-time constraints required by applications. This work presents a methodology to compare classifiers with respect to their ability to learn from classification errors on a large learning set, within a given time limit. Faster techniques may acquire more training samples, but only when they are more effective will they achieve higher performance on unseen testing sets. We demonstrate this result using several techniques, multiple datasets, and typical learning-time limits required by applications.

  3. Is Spending More Time Associated With Less Missed Care?: A Comparison of Time Use and Missed Care Across 15 Nursing Units at 2 Hospitals.

    PubMed

    McNair, Norma; Baird, Jennifer; Grogan, Tristan R; Walsh, Catherine M; Liang, Li-Jung; Worobel-Luk, Pamela; Needleman, Jack; Nuckols, Teryl K

    2016-09-01

    The aim of this study is to examine the relationship between nursing time use and perceptions of missed care. Recent literature has highlighted the problem of missed nursing care, but little is known about how nurses' time use patterns are associated with reports of missed care. In 15 nursing units at 2 hospitals, we assessed registered nurse (RN) perceptions of missed care, observed time use by RNs, and examined the relationship between time spent and degree of missed care at the nursing unit level. Patterns of time use were similar across hospitals, with 25% of time spent on documentation. For 6 different categories of nursing tasks, no association was detected between time use, including time spent on documentation, and the degree of missed care at the nursing unit level. Nursing time use cannot fully explain variation in missed care across nursing units. Further work is needed to account for patterns of missed care.

  4. Pattern formation in individual-based systems with time-varying parameters

    NASA Astrophysics Data System (ADS)

    Ashcroft, Peter; Galla, Tobias

    2013-12-01

    We study the patterns generated in finite-time sweeps across symmetry-breaking bifurcations in individual-based models. Similar to the well-known Kibble-Zurek scenario of defect formation, large-scale patterns are generated when model parameters are varied slowly, whereas fast sweeps produce a large number of small domains. The symmetry breaking is triggered by intrinsic noise, originating from the discrete dynamics at the microlevel. Based on a linear-noise approximation, we calculate the characteristic length scale of these patterns. We demonstrate the applicability of this approach in a simple model of opinion dynamics, a model in evolutionary game theory with a time-dependent fitness structure, and a model of cell differentiation. Our theoretical estimates are confirmed in simulations. In further numerical work, we observe a similar phenomenon when the symmetry-breaking bifurcation is triggered by population growth.

  5. Time-location patterns of a diverse population of older adults: the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air).

    PubMed

    Spalt, Elizabeth W; Curl, Cynthia L; Allen, Ryan W; Cohen, Martin; Adar, Sara D; Stukovsky, Karen H; Avol, Ed; Castro-Diehl, Cecilia; Nunn, Cathy; Mancera-Cuevas, Karen; Kaufman, Joel D

    2016-06-01

    The primary aim of this analysis was to present and describe questionnaire data characterizing time-location patterns of an older, multiethnic population from six American cities. We evaluated the consistency of results from repeated administration of this questionnaire and between this questionnaire and other questionnaires collected from participants of the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air). Participants reported spending most of their time inside their homes (average: 121 h/week or 72%). More than 50% of the participants reported spending no time in several of the location options, including at home outdoors, at work/volunteer/school locations indoors or outdoors, or in "other" locations outdoors. We observed consistency between self-reported time-location patterns from repeated administration of the time-location questionnaire and compared with other survey instruments. Comparisons with national cohorts demonstrated the differences in time-location patterns in the MESA Air cohort due to differences in demographics, but the data showed similar trends in patterns by age, gender, season, and employment status. This study was the first to explicitly examine the time-location patterns in an older, multiethnic population and the first to add data on Chinese participants. These data can be used to inform future epidemiological research of MESA Air and other studies that include diverse populations.

  6. Are the early predictors of long-term work absence following injury time dependent? Results from the Prospective Outcomes of Injury Study

    PubMed Central

    Lilley, Rebbecca; Davie, Gabrielle; Derrett, Sarah

    2017-01-01

    Objectives Few studies examine the influence of early predictors of work absence beyond 12 months following injury or the time-dependent relative importance of these factors. This study aimed to identify the most important sociodemographic, occupational, health, lifestyle and injury predictors of work absence at 12 and 24 months following injury and to examine changes in the relative importance of these over time. Design Prospective cohort study. Setting The Prospective Outcomes of Injury Study, New Zealand. Participants 2626 injured New Zealand workers aged 18–64 years were identified from the Prospective Outcomes of Injury Study recruited form New Zealand’s monopoly injury compensation provider injury claims register: 2092 completed the 12-month interview (80% follow-up) and 2082 completed the 24-month interview (79% follow-up). Primary and secondary outcomes measures The primary outcomes of interest was absence from work at the time of the 12-month and 24-month follow-up interviews. Results Using modified Poisson regression to estimate relative risks, important groups of workers were identified at increased risk of work absence at both 12 and 24 months: males, low-income workers, trade/manual workers, temporary employees, those reporting two or more comorbidities and those experiencing a work-related injury. Important factors unique to predicting work absence at 12 months included financial insecurity, fixed-term employment and long weekly hours worked; unique factors at 24 months included job dissatisfaction, long weekly days worked, a prior injury and sustaining an injury that was perceived to be a threat to life. Conclusions Important early predictors of work absence at 12 or 24 months following injury are multidimensional and have a time dependent pattern. A consistent set of predictors was, however, present at both time periods that are prime for early intervention. Understanding the multidimensional, time-dependent patterns of early predictors of long-term disability is important to optimally target timely interventions to prevent long-term work disability. PMID:29150466

  7. The feminisation of Canadian medicine and its impact upon doctor productivity.

    PubMed

    Weizblit, Nataly; Noble, Jason; Baerlocher, Mark Otto

    2009-05-01

    We examined the differences in work patterns between female and male doctors in Canada to gain insight into the effect of an increased number of female doctors on overall doctor productivity. Data on the practice profiles of female and male doctors across Canada were extracted from the 2007 National Physician Survey. A doctor productivity measure, 'work hours per week per population' (WHPWPP), was created, based on the number of weekly doctor hours spent providing direct patient care per 100,000 citizens. The predicted WHPWPP was calculated for a hypothetical time-point when the female and male doctor populations reach equilibrium. The differences in current and predicted WHPWPP were then analysed. Female medical students currently (2007) outnumber male medical students (at 57.8% of the medical student population). The percentage of practising doctors who are women is highest in the fields of paediatrics, obstetrics and gynaecology, psychiatry and family practice. Female doctors work an average of 47.5 hours per week (giving 30.0 hours of direct patient care), compared with 53.8 hours worked by male doctors (35.0 hours of direct patient care) (P < 0.01, chi(2) test). Female doctors tend to work less on call hours per week and see fewer patients while on-call. Female doctors are also more likely to take parental leave or a leave of absence (P < 0.01, chi(2) test). The difference in current and predicted WHPWPP was found to be 2.6%, equivalent to 1853 fewer full-time female doctors or 1588 fewer full-time male doctors. Gender appears to have a significant influence on the practice patterns of doctors in Canada. If the gender-specific work patterns described in the present study persist, an overall decrease in doctor productivity is to be anticipated.

  8. Contribution to volatile organic compound exposures from time spent in stores and restaurants and bars.

    PubMed

    Loh, Miranda M; Houseman, E Andres; Levy, Jonathan I; Spengler, John D; Bennett, Deborah H

    2009-11-01

    Many people spend time in stores and restaurants, yet there has been little investigation of the influence of these microenvironments on personal exposure. Relative to the outdoors, transportation, and the home, these microenvironments have high concentrations of several volatile organic compounds (VOCs). We developed a stochastic model to examine the effect of VOC concentrations in these microenvironments on total personal exposure for (1) non-smoking adults working in offices who spend time in stores and restaurants or bars and (2) non-smoking adults who work in these establishments. We also compared the effect of working in a smoking versus non-smoking restaurant or bar. Input concentrations for each microenvironment were developed from the literature whereas time activity inputs were taken from the National Human Activity Patterns Survey. Time-averaged exposures were simulated for 5000 individuals over a weeklong period for each analysis. Mean contributions to personal exposure from non-working time spent in stores and restaurants or bars range from <5% to 20%, depending on the VOC and time-activity patterns. At the 95th percentile of the distribution of the proportion of personal exposure attributable to time spent in stores and restaurants or bars, these microenvironments can be responsible for over half of a person's total exposure to certain VOCs. People working in restaurants or bars where smoking is allowed had the highest fraction of exposure attributable to their workplace. At the median, people who worked in stores or restaurants tended to have 20-60% of their total exposures from time spent at work. These results indicate that stores and restaurants can be large contributors to personal exposure to VOCs for both workers in those establishments and for a subset of people who visit these places, and that incorporation of these non-residential microenvironments can improve models of personal exposure distributions.

  9. Imprint lithography template technology for bit patterned media (BPM)

    NASA Astrophysics Data System (ADS)

    Lille, J.; Patel, K.; Ruiz, R.; Wu, T.-W.; Gao, H.; Wan, Lei; Zeltzer, G.; Dobisz, E.; Albrecht, T. R.

    2011-11-01

    Bit patterned media (BPM) for magnetic recording has emerged as a promising technology to deliver thermally stable magnetic storage at densities beyond 1Tb/in2. Insertion of BPM into hard disk drives will require the introduction of nanoimprint lithography and other nanofabrication processes for the first time. In this work, we focus on nanoimprint and nanofabrication challenges that are being overcome in order to produce patterned media. Patterned media has created the need for new tools and processes, such as an advanced rotary e-beam lithography tool and block copolymer integration. The integration of block copolymer is through the use of a chemical contrast pattern on the substrate which guides the alignment of di-block copolymers. Most of the work on directed self assembly for patterned media applications has, until recently, concentrated on the formation of circular dot patterns in a hexagonal close packed lattice. However, interactions between the read head and media favor a bit aspect ratio (BAR) greater than one. This design constraint has motivated new approaches for using self-assembly to create suitable high-BAR master patterns and has implications for template fabrication.

  10. Clustering change patterns using Fourier transformation with time-course gene expression data.

    PubMed

    Kim, Jaehee

    2011-01-01

    To understand the behavior of genes, it is important to explore how the patterns of gene expression change over a period of time because biologically related gene groups can share the same change patterns. In this study, the problem of finding similar change patterns is induced to clustering with the derivative Fourier coefficients. This work is aimed at discovering gene groups with similar change patterns which share similar biological properties. We developed a statistical model using derivative Fourier coefficients to identify similar change patterns of gene expression. We used a model-based method to cluster the Fourier series estimation of derivatives. We applied our model to cluster change patterns of yeast cell cycle microarray expression data with alpha-factor synchronization. It showed that, as the method clusters with the probability-neighboring data, the model-based clustering with our proposed model yielded biologically interpretable results. We expect that our proposed Fourier analysis with suitably chosen smoothing parameters could serve as a useful tool in classifying genes and interpreting possible biological change patterns.

  11. Principal Time Management Skills: Explaining Patterns in Principals' Time Use, Job Stress, and Perceived Effectiveness

    ERIC Educational Resources Information Center

    Grissom, Jason A.; Loeb, Susanna; Mitani, Hajime

    2015-01-01

    Purpose: Time demands faced by school principals make principals' work increasingly difficult. Research outside education suggests that effective time management skills may help principals meet job demands, reduce job stress, and improve their performance. The purpose of this paper is to investigate these hypotheses. Design/methodology/approach:…

  12. Trends in the Development of Alternative Work Patterns.

    ERIC Educational Resources Information Center

    McCarthy, Maureen

    1979-01-01

    Flexible scheduling and reduced work time programs can help alleviate some of the pressures on public and private employers to develop innovative solutions to problems caused by inflation, unemployment, the transition in the composition of the workforce, and changes in life-styles. (Author/IRT)

  13. Do Circadian Preferences Influence the Sleep Patterns of Night Shift Drivers?

    PubMed Central

    Narciso, Fernanda V.; Esteves, Andrea M.; Oliveira e Silva, Luciana; Bittencourt, Lia R.A.; Silva, Rogerio S.; Pires, Maria Laura N.; Tufik, Sergio; de Mello, Marco Tulio

    2013-01-01

    Objective The objective of this study was to analyze the effect of individual circadian preferences of drivers with fixed night work schedules on sleep patterns. Subjects and Methods A total of 123 professional drivers, 32 indifferent preference drivers and 91 morning preference drivers of an intermunicipality and interstate bus transportation company were evaluated. All drivers underwent polysomnographic recordings after their shifts. Furthermore, they filled out a questionnaire that contained sociodemographic and health questions. The Horne and Östberg questionnaire was used to assess the subjects' morningness-eveningness preference. Results The mean age was 42.54 ± 6.98 years and 82 (66.66%) of the drivers had worked for ≥15 years. A significant effect on rapid eye movement (REM) was observed in the morning preference drivers. They showed an increased sleep latency and an REM sleep percentage of 5% of the total REM time. This reveals a significant effect on sleep architecture associated with work time. Conclusion The drivers reported that morning preference had a significant effect on their sleep pattern indicating less REM sleep and longer REM sleep latency in the morning preference group. Thus, it is important to evaluate interactions between individual aspects of health and other parameters, such as sleep quality and work organizational factors, to promote night shift workers' health and well-being. PMID:23988815

  14. Do circadian preferences influence the sleep patterns of night shift drivers?

    PubMed

    Narciso, Fernanda V; Esteves, Andrea M; Oliveira e Silva, Luciana; Bittencourt, Lia R A; Silva, Rogerio S; Pires, Maria Laura N; Tufik, Sergio; de Mello, Marco Tulio

    2013-01-01

    The objective of this study was to analyze the effect of individual circadian preferences of drivers with fixed night work schedules on sleep patterns. A total of 123 professional drivers, 32 indifferent preference drivers and 91 morning preference drivers of an intermunicipality and interstate bus transportation company were evaluated. All drivers underwent polysomnographic recordings after their shifts. Furthermore, they filled out a questionnaire that contained sociodemographic and health questions. The Horne and Östberg questionnaire was used to assess the subjects' morningness-eveningness preference. The mean age was 42.54 ± 6.98 years and 82 (66.66%) of the drivers had worked for ≥15 years. A significant effect on rapid eye movement (REM) was observed in the morning preference drivers. They showed an increased sleep latency and an REM sleep percentage of 5% of the total REM time. This reveals a significant effect on sleep architecture associated with work time. The drivers reported that morning preference had a significant effect on their sleep pattern indicating less REM sleep and longer REM sleep latency in the morning preference group. Thus, it is important to evaluate interactions between individual aspects of health and other parameters, such as sleep quality and work organizational factors, to promote night shift workers' health and well-being. © 2013 S. Karger AG, Basel.

  15. Operational assessment of the 5-h on/10-h off watchstanding schedule on a US Navy ship: sleep patterns, mood and psychomotor vigilance performance of crewmembers in the nuclear reactor department.

    PubMed

    Shattuck, Nita Lewis; Matsangas, Panagiotis

    2016-05-01

    We assessed sleep patterns, psychomotor vigilance performance, work demands and mood of 77 crewmembers of USS NIMITZ (CVN-68) on the rotating 5-h on/10-h off (5/10) watchstanding schedule. Within the 3-day cycle of the 5/10, sleep occurred at distinctly different times each day. On two of these days, sailors typically received only brief, 4-h sleep episodes followed by periods of sustained wakefulness (approximately 22 and 20 h). Crewmembers received approximately seven hours of sleep daily, but reported excessive fatigue and dissatisfaction with their schedule. Crewmembers' mood worsened significantly over the course of the underway phase. Psychomotor vigilance performance (reaction times, lapses) was significantly degraded compared to performance when working circadian-aligned schedules. Overall, standing watch on the 5/10 schedule, combined with other work duties, resulted in poor sleep hygiene. Crewmembers on the 5/10 experienced periodic bouts of sustained wakefulness and accrued a significant sleep debt due to extended workdays and circadian-misaligned sleep. Practitioner summary: We assessed crewmembers' sleep patterns, psychomotor vigilance performance and work demands when working a rotating 5-h on/10-h off (5/10) watchstanding schedule. The 5/10, combined with other work duties, resulted in poor sleep hygiene. Crewmembers experienced periodic bouts of sustained wakefulness and accrued a significant sleep debt due to extended workdays and circadian-misaligned sleep.

  16. The time course of individual face recognition: A pattern analysis of ERP signals.

    PubMed

    Nemrodov, Dan; Niemeier, Matthias; Mok, Jenkin Ngo Yin; Nestor, Adrian

    2016-05-15

    An extensive body of work documents the time course of neural face processing in the human visual cortex. However, the majority of this work has focused on specific temporal landmarks, such as N170 and N250 components, derived through univariate analyses of EEG data. Here, we take on a broader evaluation of ERP signals related to individual face recognition as we attempt to move beyond the leading theoretical and methodological framework through the application of pattern analysis to ERP data. Specifically, we investigate the spatiotemporal profile of identity recognition across variation in emotional expression. To this end, we apply pattern classification to ERP signals both in time, for any single electrode, and in space, across multiple electrodes. Our results confirm the significance of traditional ERP components in face processing. At the same time though, they support the idea that the temporal profile of face recognition is incompletely described by such components. First, we show that signals associated with different facial identities can be discriminated from each other outside the scope of these components, as early as 70ms following stimulus presentation. Next, electrodes associated with traditional ERP components as well as, critically, those not associated with such components are shown to contribute information to stimulus discriminability. And last, the levels of ERP-based pattern discrimination are found to correlate with recognition accuracy across subjects confirming the relevance of these methods for bridging brain and behavior data. Altogether, the current results shed new light on the fine-grained time course of neural face processing and showcase the value of novel methods for pattern analysis to investigating fundamental aspects of visual recognition. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Sibling Similarities and Differences in Time Use: A Pattern-Analytic, Within-Family Approach

    ERIC Educational Resources Information Center

    Shanahan, Lilly; Kim, Ji-Yeon; McHale, Susan M.; Crouter, Ann C.

    2007-01-01

    Similarities and differences in adolescent siblings' free time activities were investigated. Firstborns and second-borns from 181 predominantly White, working, and middle-class families reported on their time use and sibling relationships. Their parents reported on their socioeconomic status and neighborhood characteristics. Cluster analysis…

  18. Emergent scar lines in chaotic advection of passive directors

    NASA Astrophysics Data System (ADS)

    Hejazi, Bardia; Mehlig, Bernhard; Voth, Greg A.

    2017-12-01

    We examine the spatial field of orientations of slender fibers that are advected by a two-dimensional fluid flow. The orientation field of these passive directors are important in a wide range of industrial and geophysical flows. We introduce emergent scar lines as the dominant coherent structures in the orientation field of passive directors in chaotic flows. Previous work has identified the existence of scar lines where the orientation rotates by π over short distances, but the lines that were identified disappeared as time progressed. As a result, earlier work focused on topological singularities in the orientation field, which we find to play a negligible role at long times. We use the standard map as a simple time-periodic two-dimensional flow that produces Lagrangian chaos. This class of flows produces persistent patterns in passive scalar advection and we find that a different kind of persistent pattern develops in the passive director orientation field. We identify the mechanism by which emergent scar lines grow to dominate these patterns at long times in complex flows. Emergent scar lines form where the recent stretching of the fluid element is perpendicular to earlier stretching. Thus these scar lines can be labeled by their age, defined as the time since their stretching reached a maximum.

  19. Hybrid model for forecasting time series with trend, seasonal and salendar variation patterns

    NASA Astrophysics Data System (ADS)

    Suhartono; Rahayu, S. P.; Prastyo, D. D.; Wijayanti, D. G. P.; Juliyanto

    2017-09-01

    Most of the monthly time series data in economics and business in Indonesia and other Moslem countries not only contain trend and seasonal, but also affected by two types of calendar variation effects, i.e. the effect of the number of working days or trading and holiday effects. The purpose of this research is to develop a hybrid model or a combination of several forecasting models to predict time series that contain trend, seasonal and calendar variation patterns. This hybrid model is a combination of classical models (namely time series regression and ARIMA model) and/or modern methods (artificial intelligence method, i.e. Artificial Neural Networks). A simulation study was used to show that the proposed procedure for building the hybrid model could work well for forecasting time series with trend, seasonal and calendar variation patterns. Furthermore, the proposed hybrid model is applied for forecasting real data, i.e. monthly data about inflow and outflow of currency at Bank Indonesia. The results show that the hybrid model tend to provide more accurate forecasts than individual forecasting models. Moreover, this result is also in line with the third results of the M3 competition, i.e. the hybrid model on average provides a more accurate forecast than the individual model.

  20. Profiles of verbal working memory growth predict speech and language development in children with cochlear implants.

    PubMed

    Kronenberger, William G; Pisoni, David B; Harris, Michael S; Hoen, Helena M; Xu, Huiping; Miyamoto, Richard T

    2013-06-01

    Verbal short-term memory (STM) and working memory (WM) skills predict speech and language outcomes in children with cochlear implants (CIs) even after conventional demographic, device, and medical factors are taken into account. However, prior research has focused on single end point outcomes as opposed to the longitudinal process of development of verbal STM/WM and speech-language skills. In this study, the authors investigated relations between profiles of verbal STM/WM development and speech-language development over time. Profiles of verbal STM/WM development were identified through the use of group-based trajectory analysis of repeated digit span measures over at least a 2-year time period in a sample of 66 children (ages 6-16 years) with CIs. Subjects also completed repeated assessments of speech and language skills during the same time period. Clusters representing different patterns of development of verbal STM (digit span forward scores) were related to the growth rate of vocabulary and language comprehension skills over time. Clusters representing different patterns of development of verbal WM (digit span backward scores) were related to the growth rate of vocabulary and spoken word recognition skills over time. Different patterns of development of verbal STM/WM capacity predict the dynamic process of development of speech and language skills in this clinical population.

  1. Health-related Quality of Life and Related Factors in Full-time and Part-time Workers.

    PubMed

    Kim, Byungsung; Kim, Wonjoon; Choi, Hyunrim; Won, Changwon; Kim, Youngshin

    2012-07-01

    There has been a rapid increase in the number of part-time workers in Korea with little information available on associated changes in quality of life. This study was designed to compare part-time and full-time workers in terms of the quality of life and related factors. Data were extracted from the 4th Korea National Health and Nutrition Examination Survey, conducted in 2008. Of the 1,284 participants selected, 942 were females (range, 20 to 64 years). Based on the information provided by self-administered questionnaire, subjects were categorized according to the working pattern (full-time and part-time) and working hours (<30 and ≥30 hours). Differences in socio-demographic characteristics, health-related behaviors, and job characteristics were assessed by t-test and chi-square test. EuroQol-five dimensions (EQ-5D) index was implemented in order to measure the quality of life. Differences in the EQ-5D index scores between the groups were compared by t-test, stepwise multivariate logistic regression analyses. Quality of life did not differ by work patterns. In males, the Organization for Economic Cooperation and Development part-time group was associated with poorer quality of life (odds ratio [OR], 0.49; P = 0.028). For both sexes, the non-stress group was linked with superior quality of life in comparison to the stress group (OR, 2.64; P = 0.002; OR, 2.17; P < 0.001). Female employees engaged in non-manual labor had superior quality of life than those engaged in manual labor (OR, 1.40; P = 0.027). This study concludes that working less than 30 hours per week is related to lower quality of life in comparison to working 30 hours or more in male employees in Korea.

  2. Microscopic 3D measurement of dynamic scene using optimized pulse-width-modulation binary fringe

    NASA Astrophysics Data System (ADS)

    Hu, Yan; Chen, Qian; Feng, Shijie; Tao, Tianyang; Li, Hui; Zuo, Chao

    2017-10-01

    Microscopic 3-D shape measurement can supply accurate metrology of the delicacy and complexity of MEMS components of the final devices to ensure their proper performance. Fringe projection profilometry (FPP) has the advantages of noncontactness and high accuracy, making it widely used in 3-D measurement. Recently, tremendous advance of electronics development promotes 3-D measurements to be more accurate and faster. However, research about real-time microscopic 3-D measurement is still rarely reported. In this work, we effectively combine optimized binary structured pattern with number-theoretical phase unwrapping algorithm to realize real-time 3-D shape measurement. A slight defocusing of our proposed binary patterns can considerably alleviate the measurement error based on phase-shifting FPP, making the binary patterns have the comparable performance with ideal sinusoidal patterns. Real-time 3-D measurement about 120 frames per second (FPS) is achieved, and experimental result of a vibrating earphone is presented.

  3. Estimated activity patterns in British 45 year olds: cross-sectional findings from the 1958 British birth cohort.

    PubMed

    Parsons, T J; Thomas, C; Power, C

    2009-08-01

    To investigate patterns of, and associations between, physical activity at work and in leisure time, television viewing and computer use. 4531 men and 4594 women with complete plausible data, age 44-45 years, participating in the 1958 British birth cohort study. Physical activity, television viewing and computer use (hours/week) were estimated using a self-complete questionnaire and intensity (MET hours/week) derived for physical activity. Relationships were investigated using linear regression and chi(2) tests. From a target sample of 11,971, 9223 provided information on physical activity, of whom 75 and 47% provided complete and plausible activity data on work and leisure time activity respectively. Men and women spent a median of 40.2 and 34.2 h/week, respectively in work activity, and 8.3 and 5.8 h/week in leisure activity. Half of all participants watched television for > or =2 h/day, and half used a computer for <1 h/day. Longer work hours were not associated with a shorter duration of leisure activity, but were associated with a shorter duration of computer use (men only). In men, higher work MET hours were associated with higher leisure-time MET hours, and shorter durations of television viewing and computer use. Watching more television was related to fewer hours or MET hours of leisure activity, as was longer computer use in men. Longer computer use was related to more hours (or MET hours) in leisure activities in women. Physical activity levels at work and in leisure time in mid-adulthood are low. Television viewing (and computer use in men) may compete with leisure activity for time, whereas longer duration of work hours is less influential. To change active and sedentary behaviours, better understanding of barriers and motivators is needed.

  4. Optical properties of electrohydrodynamic convection patterns: rigorous and approximate methods.

    PubMed

    Bohley, Christian; Heuer, Jana; Stannarius, Ralf

    2005-12-01

    We analyze the optical behavior of two-dimensionally periodic structures that occur in electrohydrodynamic convection (EHC) patterns in nematic sandwich cells. These structures are anisotropic, locally uniaxial, and periodic on the scale of micrometers. For the first time, the optics of these structures is investigated with a rigorous method. The method used for the description of the electromagnetic waves interacting with EHC director patterns is a numerical approach that discretizes directly the Maxwell equations. It works as a space-grid-time-domain method and computes electric and magnetic fields in time steps. This so-called finite-difference-time-domain (FDTD) method is able to generate the fields with arbitrary accuracy. We compare this rigorous method with earlier attempts based on ray-tracing and analytical approximations. Results of optical studies of EHC structures made earlier based on ray-tracing methods are confirmed for thin cells, when the spatial periods of the pattern are sufficiently large. For the treatment of small-scale convection structures, the FDTD method is without alternatives.

  5. Real-time operation without a real-time operating system for instrument control and data acquisition

    NASA Astrophysics Data System (ADS)

    Klein, Randolf; Poglitsch, Albrecht; Fumi, Fabio; Geis, Norbert; Hamidouche, Murad; Hoenle, Rainer; Looney, Leslie; Raab, Walfried; Viehhauser, Werner

    2004-09-01

    We are building the Field-Imaging Far-Infrared Line Spectrometer (FIFI LS) for the US-German airborne observatory SOFIA. The detector read-out system is driven by a clock signal at a certain frequency. This signal has to be provided and all other sub-systems have to work synchronously to this clock. The data generated by the instrument has to be received by a computer in a timely manner. Usually these requirements are met with a real-time operating system (RTOS). In this presentation we want to show how we meet these demands differently avoiding the stiffness of an RTOS. Digital I/O-cards with a large buffer separate the asynchronous working computers and the synchronous working instrument. The advantage is that the data processing computers do not need to process the data in real-time. It is sufficient that the computer can process the incoming data stream on average. But since the data is read-in synchronously, problems of relating commands and responses (data) have to be solved: The data is arriving at a fixed rate. The receiving I/O-card buffers the data in its buffer until the computer can access it. To relate the data to commands sent previously, the data is tagged by counters in the read-out electronics. These counters count the system's heartbeat and signals derived from that. The heartbeat and control signals synchronous with the heartbeat are sent by an I/O-card working as pattern generator. Its buffer gets continously programmed with a pattern which is clocked out on the control lines. A counter in the I/O-card keeps track of the amount of pattern words clocked out. By reading this counter, the computer knows the state of the instrument or knows the meaning of the data that will arrive with a certain time-tag.

  6. Healthy Time Use in the Encore Years: Do Work, Resources, Relations, and Gender Matter?*

    PubMed Central

    Flood, Sarah M.; Moen, Phyllis

    2015-01-01

    Social engagement is theorized to promote health, with ages 55 to 75 – what some call “encore” adulthood – potentially a time for ongoing engagement or social isolation. We use the American Time Use Survey (N=11,952) and a life course perspective to examine associations between paid work, resources, relations, and healthy time use for men and women in the first (55–64) and second (65–74) halves of the encore years. Work limits sufficient sleep (full-time working men) and television watching (all workers) but also time spent in physical activity (full-time workers). College-educated and healthy encore adults – across age and gender divides – are more likely to exercise and watch less television. Marriage and caregiving encourage socializing and limit television watching, despite differential effects on physical activity and sleep. These findings fit well with a gendered life course perspective suggesting socially patterned (by work, resources, relationships, gender, age) health behaviors. PMID:25722126

  7. Healthy time use in the encore years: do work, resources, relations, and gender matter?

    PubMed

    Flood, Sarah M; Moen, Phyllis

    2015-03-01

    Social engagement is theorized to promote health, with ages 55 to 75-what some call "encore" adulthood-potentially being a time for ongoing engagement or social isolation. We use the American Time Use Survey (N = 11,952) and a life course perspective to examine associations between paid work, resources, relations, and healthy time use for men and women in the first (55-64) and second (65-74) halves of the encore years. Work limits sufficient sleep (full-time working men) and television watching (all workers) but also time spent in physical activity (full-time workers). College-educated and healthy encore adults-across age and gender divides-are more likely to exercise and watch less television. Marriage and caregiving encourage socializing and limit television watching, despite differential effects on physical activity and sleep. These findings fit well with a gendered life course perspective suggesting socially patterned (by work, resources, relationships, gender, age) health behaviors. © American Sociological Association 2015.

  8. Signs of Change? At-Home and Breadwinner Parents' Housework and Child-Care Time.

    PubMed

    Chesley, Noelle; Flood, Sarah

    2017-04-01

    We analyze American Time Use Survey (ATUS) data to examine patterns in domestic work among at-home and breadwinner parents to further gauge how time availability, relative earnings, and gender shape time use in couples with extreme differences in earnings and work hours. We find that involvement in female-typed housework is an important driver of overall housework time. It is counter-normative housework behavior by at-home fathers that shapes conclusions about how time availability, relative resources, and gender influence parents' housework. While time availability appears to shape child care in comparable ways across parents, mothers are more engaged in child care than similarly-situated fathers. Overall, our comparisons point to the importance of distinguishing among gender-normative housework tasks and accounting for differences in engagement on work and non-work days. Our results also provide a basis for assessing the social significance of growing numbers of parents in work-family roles that are not gender-normative.

  9. Signs of Change? At-Home and Breadwinner Parents’ Housework and Child-Care Time

    PubMed Central

    Chesley, Noelle; Flood, Sarah

    2016-01-01

    We analyze American Time Use Survey (ATUS) data to examine patterns in domestic work among at-home and breadwinner parents to further gauge how time availability, relative earnings, and gender shape time use in couples with extreme differences in earnings and work hours. We find that involvement in female-typed housework is an important driver of overall housework time. It is counter-normative housework behavior by at-home fathers that shapes conclusions about how time availability, relative resources, and gender influence parents’ housework. While time availability appears to shape child care in comparable ways across parents, mothers are more engaged in child care than similarly-situated fathers. Overall, our comparisons point to the importance of distinguishing among gender-normative housework tasks and accounting for differences in engagement on work and non-work days. Our results also provide a basis for assessing the social significance of growing numbers of parents in work-family roles that are not gender-normative. PMID:28596619

  10. A driving simulator study : evaluation of vehicle mounted attenuator markings in work zones during different times of the day.

    DOT National Transportation Integrated Search

    2010-09-01

    This report presents a study of driver perceptions using a driving simulator carried out on the : effectiveness of four markings which vary in striping patterns and color combinations used at the : rear of vehicle mounted attenuators (VMAs) in work z...

  11. Retirement Patterns from Career Employment

    ERIC Educational Resources Information Center

    Cahill, Kevin E.; Giandrea, Michael D.; Quinn, Joseph F.

    2006-01-01

    Purpose: This article investigates how older Americans leave their career jobs and estimates the extent of intermediate labor force activity (bridge jobs) between full-time work on a career job and complete labor-force withdrawal. Design and Methods: Using data from the Health and Retirement Study, we explored the work histories and retirement…

  12. Variations In Predicted Employment-related Tripmaking Caused By Alternate Systems Of Job Classification

    DOT National Transportation Integrated Search

    1997-01-01

    The purposes of this paper are to describe how the locational patterns of jobs, and the arrival time of home-to-work trips, vary according to the system used to classify jobs. SEMCOG has obtained a special cross-tabulation of 1990 census data on work...

  13. Comparison of Retention Patterns for Army National Guard and Army Reserve Units Participating in National Training Center, Reforger and Blazing Trails Exercises

    DTIC Science & Technology

    1990-01-01

    Department of the Army RAND Corp. Accesion Fo, NTIS CRA&I Technical review by DTIC ! A6 0Undnno s: ced 0 David K. Home tl IC I Robert W. Tinney By Dist...changes to the Sixth Quadrennial Review of Military Compensation. viii COMPARISON OF RETENTION PATTERNS FOR NATIONAL GUARD AND ARMY RESERVE UNITS...duty time-- movies , volleyball, and time to go to the PX at Big Bear. Because of the work schedule, the soldiers did not have any free time in the

  14. Switching among graphic patterns is governed by oscillatory coordination dynamics: implications for understanding handwriting

    PubMed Central

    Zanone, Pier-Giorgio; Athènes, Sylvie

    2013-01-01

    Revisiting an original idea by Hollerbach (1981), previous work has established that the production of graphic shapes, assumed to be the blueprint for handwriting, is governed by the dynamics of orthogonal non-linear coupled oscillators. Such dynamics determines few stable coordination patterns, giving rise to a limited set of preferred graphic shapes, namely, four lines and four ellipsoids independent of orientation. The present study investigates the rules of switching among such graphic coordination patterns. Seven participants were required to voluntarily switch within twelve pairs of shapes presented on a graphic tablet. In line with previous theoretical and experimental work on bimanual coordination, results corroborated our hypothesis that the relative stability of the produced coordination patterns determines the time needed for switching: the transition to a more stable pattern was shorter, and inversely. Moreover, switching between patterns with the same orientation but different eccentricities was faster than with a change in orientation. Nonetheless, the switching time covaried strictly with the change in relative phase effected by the transition between two shapes, whether this implied a change in eccentricity or in orientation. These findings suggest a new operational definition of what the (motor) units or strokes of handwriting are and shed a novel light on how coarticulation and recruitment of degrees of freedom may occur in graphic skills. They also yield some leads for understanding the acquisition and the neural underpinnings of handwriting. PMID:24069014

  15. EB Ford revisited: assessing the long-term stability of wing-spot patterns and population genetic structure of the meadow brown butterfly on the Isles of Scilly

    PubMed Central

    Baxter, S W; Hoffman, J I; Tregenza, T; Wedell, N; Hosken, D J

    2017-01-01

    Understanding selection in the wild remains a major aim of evolutionary ecology and work by Ford and colleagues on the meadow brown butterfly Maniola jurtina did much to ignite this agenda. A great deal of their work was conducted during the 1950s on the Isles of Scilly. They documented island-specific wing-spot patterns that remained consistent over about a decade, but patterns on some islands changed after environmental perturbation. It was suggested that these wing-spot patterns reflected island-specific selection and that there was little migration between islands. However, genetic studies to test the underlying assumption of restricted migration are lacking and it is also unknown whether the originally described wing-spot patterns have persisted over time. We therefore collected female butterflies from five of Ford's original study locations, including three large islands (St Mary's, St Martin's and Tresco) and two small islands (Tean and St Helen's). Wing-spot patterns had not changed appreciably over time on three of the islands (two large and one small), but were significantly different on the other two. Furthermore, analysis of 176 amplified fragment length polymorphisms revealed significant genome-wide differentiation among the five islands. Our findings are consistent with Ford's conclusions that despite the close proximity of these islands, there is restricted gene flow among them. PMID:27804964

  16. Gender Dynamics in Mexican American Families: Connecting Mothers’, Fathers’, and Youths’ Experiences

    PubMed Central

    Lam, Chun Bun; McHale, Susan M.; Updegraff, Kimberly A.

    2013-01-01

    Study goals were to examine the conditions under which congruent and incongruent patterns of parents’ division of household labor and gender role attitudes emerged, and the implications of these patterns for youth gender development. Questionnaire and phone diary data were collected from mothers, fathers, and youths from 236 Mexican American families in the southwestern US. Preliminary cluster analysis identified three patterns: Traditional divisions of labor and traditional attitudes, egalitarian divisions of labor and egalitarian attitudes, and an incongruent pattern, with a traditional division of labor but egalitarian attitudes. MANOVAs, and follow-up, mixed- and between-group ANOVAs, revealed that these groups of families differed in parents’ time constraints, socioeconomic resources, and cultural orientations. Mothers in the congruent egalitarian group worked more hours and earned higher incomes as compared to mothers in the congruent traditional and incongruent groups, and the emergence of the incongruent group was grounded in within-family, inter-parental differences in work hours and incomes. Parents’ patterns of gendered practices and beliefs were linked to their youths’ housework participation, time with mothers versus fathers, and gender role attitudes. Youths in the congruent traditional group had more traditional gender role attitudes than those in the congruent egalitarian and incongruent groups, and gender atypical housework participation and time with parents were only observed in the congruent egalitarian group. Findings demonstrate the utility of a within-family design to understand complex gendered phenomena, and highlight the multidimensional nature of gender and the importance of contextualizing the study of ethnic minorities. PMID:23641122

  17. It Comes With the Job: Work Organizational, Job Design, and Self-Regulatory Barriers to Improving the Health Status of Train Drivers.

    PubMed

    Naweed, Anjum; Chapman, Janine; Allan, Matthew; Trigg, Joshua

    2017-03-01

    This study aimed to examine the impacts of key barriers to improving the occupational health status of Australian train drivers. From May to June, 2015, five semi-structured qualitative focus groups were conducted with 29 train drivers from South Australian, Victorian, and New South Wales-based rail organizations in Australia. Occupational health was impeded by multiple barriers regarding sleep (patterns/fatigue), diet (planning/context), mental health (occupational stress), rostering (low autonomy), sedentary time, low fitness motivation, and family/social life conflicts. Work organizational barriers included communication issues, low organizational support, and existing social norms. Job design barriers included rostering, fatigue, stimulant reliance, and family/social life imbalances. Self-regulatory barriers included dietary and exercise patterns habits and patterns. Occupational health interventions for Australian train drivers must address work organizational, job design, and self-regulatory barriers to healthier lifestyle behaviors.

  18. Muscle activity patterns and spinal shrinkage in office workers using a sit-stand workstation versus a sit workstation.

    PubMed

    Gao, Ying; Cronin, Neil J; Pesola, Arto J; Finni, Taija

    2016-10-01

    Reducing sitting time by means of sit-stand workstations is an emerging trend, but further evidence is needed regarding their health benefits. This cross-sectional study compared work time muscle activity patterns and spinal shrinkage between office workers (aged 24-62, 58.3% female) who used either a sit-stand workstation (Sit-Stand group, n = 10) or a traditional sit workstation (Sit group, n = 14) for at least the past three months. During one typical workday, muscle inactivity and activity from quadriceps and hamstrings were monitored using electromyography shorts, and spinal shrinkage was measured using stadiometry before and after the workday. Compared with the Sit group, the Sit-Stand group had less muscle inactivity time (66.2 ± 17.1% vs. 80.9 ± 6.4%, p = 0.014) and more light muscle activity time (26.1 ± 12.3% vs. 14.9 ± 6.3%, p = 0.019) with no significant difference in spinal shrinkage (5.62 ± 2.75 mm vs. 6.11 ± 2.44 mm). This study provides evidence that working with sit-stand workstations can promote more light muscle activity time and less inactivity without negative effects on spinal shrinkage. Practitioner Summary: This cross-sectional study compared the effects of using a sit-stand workstation to a sit workstation on muscle activity patterns and spinal shrinkage in office workers. It provides evidence that working with a sit-stand workstation can promote more light muscle activity time and less inactivity without negative effects on spinal shrinkage.

  19. Pediatricians Working Part-Time Has Plateaued.

    PubMed

    Cull, William L; Frintner, Mary Pat; O'Connor, Karen G; Olson, Lynn M

    2016-04-01

    To examine trends in pediatricians working part-time and residents seeking part-time work and to examine associated characteristics. The American Academy of Pediatrics (AAP) Periodic Survey of Fellows and the AAP Annual Survey of Graduating Residents were used to examine part-time employment. Fourteen periodic surveys were combined with an overall response rate of 57%. Part-time percentages were compared for surveys conducted from 2006-2009 and 2010-2013. The AAP Annual Surveys of Graduating Residents (combined response rate = 60%) from 2006-2009 were compared with 2010-2013 surveys for residents seeking and obtaining part-time positions following training. Multivariable logistic regression models identified characteristics associated with part-time work. Comparable percentages of pediatricians worked part-time in 2006-2009 (23%) and 2010-2013 (23%). There was similarly no statistically significant difference in residents seeking part-time work (30%-28%), and there was a slight decline in residents accepting part-time work (16%-13%, aOR .75, 95% CI .56-.96). Increases in working part-time were not found for any subgroups examined. Women consistently were more likely than men to work part-time (35% vs 9%), but they showed different patterns of part-time work across age. Women in their 40s (40%) were more likely than other women (33%) and men in their 60s (20%) were more likely than other men (5%) to work part-time. There has been a levelling off in the number of pediatricians working part-time and residents seeking part-time work. Overall, women remain more likely to work part-time, although 1 in 5 men over 60 work part-time. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Finding time over time: Longitudinal links between employed mothers' work-family conflict and time profiles.

    PubMed

    Lee, Soomi; McHale, Susan M; Crouter, Ann C; Hammer, Leslie B; Almeida, David M

    2017-08-01

    Drawing upon the Work-Home Resources model (ten Brummelhuis & Bakker, 2012), this study examined the links between work-family conflict and employed mothers' profiles of time resources for work and parenting roles. Using a person-centered latent profile approach, we identified 3 profiles of time use and perceived time adequacy in a sample of mothers employed in the extended-care industry (N = 440): a Work-Oriented profile, characterized by spending relatively more time at work, perceiving lower time adequacy for work, spending less time with children, and perceiving lower time adequacy for children; a Parenting-Oriented profile, characterized by the opposite pattern; and a Role-Balanced profile, characterized by average levels across the 4 dimensions. Mothers in the Work-Oriented profile reported greater work-to-family conflict and family to-work conflict than those in the Role-Balanced and Parenting-Oriented profiles. Greater work-to-family conflict was linked to membership in the Work-Oriented profile, net of personal, family, and work characteristics. Longitudinal latent profile transition analysis showed that increases in work-to-family conflict across 12 months were linked to greater odds of moving toward the Work-Oriented profile (relative to staying in the same profile), whereas decreases in work-to-family conflict were linked to greater odds of moving toward the Parenting-Oriented profile. Results illuminate the heterogeneity in how employed mothers perceive and allocate time in work and parenting roles and suggest that decreasing work-to-family conflict may preserve time resources for parenting. Intervention efforts should address ways of increasing employees' family time resources and decreasing work-family conflict. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  1. Recurrent Neural Networks for Multivariate Time Series with Missing Values.

    PubMed

    Che, Zhengping; Purushotham, Sanjay; Cho, Kyunghyun; Sontag, David; Liu, Yan

    2018-04-17

    Multivariate time series data in practical applications, such as health care, geoscience, and biology, are characterized by a variety of missing values. In time series prediction and other related tasks, it has been noted that missing values and their missing patterns are often correlated with the target labels, a.k.a., informative missingness. There is very limited work on exploiting the missing patterns for effective imputation and improving prediction performance. In this paper, we develop novel deep learning models, namely GRU-D, as one of the early attempts. GRU-D is based on Gated Recurrent Unit (GRU), a state-of-the-art recurrent neural network. It takes two representations of missing patterns, i.e., masking and time interval, and effectively incorporates them into a deep model architecture so that it not only captures the long-term temporal dependencies in time series, but also utilizes the missing patterns to achieve better prediction results. Experiments of time series classification tasks on real-world clinical datasets (MIMIC-III, PhysioNet) and synthetic datasets demonstrate that our models achieve state-of-the-art performance and provide useful insights for better understanding and utilization of missing values in time series analysis.

  2. Dietary patterns among Norwegian 2-year-olds in 1999 and in 2007 and associations with child and parent characteristics.

    PubMed

    Kristiansen, Anne Lene; Lande, Britt; Sexton, Joseph Andrew; Andersen, Lene Frost

    2013-07-14

    Infant and childhood nutrition influences short- and long-term health. The objective of the present paper has been to explore dietary patterns and their associations with child and parent characteristics at two time points. Parents of Norwegian 2-year-olds were, in 1999 (n 3000) and in 2007 (n 2984), invited to participate in a national dietary survey. At both time points, diet was assessed by a semi-quantitative FFQ that also provided information on several child and parent characteristics. A total of 1373 participants in the 1999 sample and 1472 participants in the 2007 sample were included in the analyses. Dietary patterns were identified by principal components analysis and related to child and parent characteristics using the general linear model. Four dietary patterns were identified at each time point. The 'unhealthy' and 'healthy' patterns in 1999 and 2007 showed similarities with regard to loadings of food groups. Both the 'bread and spread-based' pattern in 1999 and the 'traditional' pattern in 2007 had high positive loadings for bread and spreads; however, the 'traditional' pattern did also include positive associations with a warm meal. The last patterns identified in 1999 and in 2007 were not comparable with regard to loadings of food groups. All dietary patterns were significantly associated with one or several child and parent characteristics. In conclusion, the 'unhealthy' patterns in 1999 and in 2007 showed similarities with regard to loadings of food groups and were, at both time points, associated with sex, breastfeeding at 12 months of age, parity, maternal age and maternal work situation.

  3. It's about time: Presentation in honor of Ira Hirsh

    NASA Astrophysics Data System (ADS)

    Grant, Ken

    2002-05-01

    Over his long and illustrious career, Ira Hirsh has returned time and time again to his interest in the temporal aspects of pattern perception. Although Hirsh has studied and published articles and books pertaining to many aspects of the auditory system, such as sound conduction in the ear, cochlear mechanics, masking, auditory localization, psychoacoustic behavior in animals, speech perception, medical and audiological applications, coupling between psychophysics and physiology, and ecological acoustics, it is his work on auditory timing of simple and complex rhythmic patterns, the backbone of speech and music, that are at the heart of his more recent work. Here, we will focus on several aspects of temporal processing of simple and complex signals, both within and across sensory systems. Data will be reviewed on temporal order judgments of simple tones, and simultaneity judgments and intelligibility of unimodal and bimodal complex stimuli where stimulus components are presented either synchronously or asynchronously. Differences in the symmetry and shape of ``temporal windows'' derived from these data sets will be highlighted.

  4. Temporal patterns of mental model convergence: implications for distributed teams interacting in electronic collaboration spaces.

    PubMed

    McComb, Sara; Kennedy, Deanna; Perryman, Rebecca; Warner, Norman; Letsky, Michael

    2010-04-01

    Our objective is to capture temporal patterns in mental model convergence processes and differences in these patterns between distributed teams using an electronic collaboration space and face-to-face teams with no interface. Distributed teams, as sociotechnical systems, collaborate via technology to work on their task. The way in which they process information to inform their mental models may be examined via team communication and may unfold differently than it does in face-to-face teams. We conducted our analysis on 32 three-member teams working on a planning task. Half of the teams worked as distributed teams in an electronic collaboration space, and the other half worked face-to-face without an interface. Using event history analysis, we found temporal interdependencies among the initial convergence points of the multiple mental models we examined. Furthermore, the timing of mental model convergence and the onset of task work discussions were related to team performance. Differences existed in the temporal patterns of convergence and task work discussions across conditions. Distributed teams interacting via an electronic interface and face-to-face teams with no interface converged on multiple mental models, but their communication patterns differed. In particular, distributed teams with an electronic interface required less overall communication, converged on all mental models later in their life cycles, and exhibited more linear cognitive processes than did face-to-face teams interacting verbally. Managers need unique strategies for facilitating communication and mental model convergence depending on teams' degrees of collocation and access to an interface, which in turn will enhance team performance.

  5. Patterns of workplace supervisor support desired by abused women.

    PubMed

    Perrin, Nancy A; Yragui, Nanette L; Hanson, Ginger C; Glass, Nancy

    2011-07-01

    The purpose of this study was to understand differences in patterns of supervisor support desired by female victims of intimate partner violence (IPV) and to examine whether the pattern of support desired at work is reflective of a woman's stage of change in the abusive relationship, IPV-related work interference, and IPV-related job reprimands or job loss. We conducted interviews in Spanish or English with adult women working in low-income jobs who had been physically or sexually abused by an intimate partner/ ex-partner in the past year ( N = 133). Cluster analysis revealed three distinct clusters that form a hierarchy of type of support wanted: those who desired limited support; those who desired confidential, time-off, and emotional support; and those who desired support in wide variety of ways from their supervisor. The clusters appeared to reflect stages of behavior change in an abusive relationship. Specifically, the limited-support cluster may represent an early precontemplation stage, with women reporting the least interference with work. The support-in-every-way cluster may represent later stages of change, in which women are breaking away from the abusive partner and report the greatest interference with work. Women in the confidential-, time-off-, and emotional-support cluster are in a transition stage in which they are considering change and are exploring options in their abusive relationship. Understanding the hierarchy of the type of support desired, and its relationship to stages of change in the abusive relationship and work interference, may provide a strong foundation for developing appropriate and effective workplace interventions to guide supervisors in providing support to women experiencing IPV.

  6. Development of template and mask replication using jet and flash imprint lithography

    NASA Astrophysics Data System (ADS)

    Brooks, Cynthia; Selinidis, Kosta; Doyle, Gary; Brown, Laura; LaBrake, Dwayne; Resnick, Douglas J.; Sreenivasan, S. V.

    2010-09-01

    The Jet and Flash Imprint Lithography (J-FILTM)1-7 process uses drop dispensing of UV curable resists to assist high resolution patterning for subsequent dry etch pattern transfer. The technology is actively being used to develop solutions for memory markets including Flash memory and patterned media for hard disk drives. It is anticipated that the lifetime of a single template (for patterned media) or mask (for semiconductor) will be on the order of 104 - 105 imprints. This suggests that tens of thousands of templates/masks will be required. It is not feasible to employ electronbeam patterning directly to deliver these volumes. Instead, a "master" template - created by directly patterning with an electron-beam tool - will be replicated many times with an imprint lithography tool to produce the required supply of "working" templates/masks. In this paper, we review the development of the pattern transfer process for both template and mask replicas. Pattern transfer of resolutions down to 25nm has been demonstrated for bit patterned media replication. In addition, final resolution on a semiconductor mask of 28nm has been confirmed. The early results on both etch depth and CD uniformity are promising, but more extensive work is required to characterize the pattern transfer process.

  7. [Organization of socially acceptable working hours in nursing].

    PubMed

    Büssing, A; Glaser, J

    1994-05-01

    Three dimensions in the structure of the working hour system of nurses, rendering them socially acceptable, are becoming important: duration of the working day, the time of day which is being worked and the distribution of working hours. The latter two are of particular importance because flexible shift is becoming the dominant pattern in nursing. Six indicators are discussed as criteria for social acceptability: security of employment which includes access to the labour-market, level of income, health, opportunity for social relationships, social participation, and autonomy. Responses of 297 nurses in one General Hospital taking part in a study, were analysed to examine empirically the concept of 'socially acceptable structure of the working hours'. Ideal and factual patterns are considered first. Secondly aspects of autonomy are considered and the way this depends on time, thirdly the criteria used to define 'social acceptability' are examined for validity. Results show firstly the cross contrast between the hospital's expectation and the nurses' wishes with regard to working hours. Furthermore, inspite of the demand for flexibility, staff have very little choice and there is little sign of joint decision making. Thirdly results show that health, interpersonal and social aspects are of special importance and that, correspondingly, in the view of nurses, financial and practical problems are of lesser importance in their every day life.

  8. Time for children: trends in the employment patterns of parents, 1967-2009.

    PubMed

    Fox, Liana; Han, Wen-Jui; Ruhm, Christopher; Waldfogel, Jane

    2013-02-01

    Using data from the 1967-2009 years of the March Current Population Surveys (CPS), we examine two important resources for children's well-being: time and money. We document trends in parental employment, from the perspective of children, and show what underlies these trends. We find that increases in family work hours mainly reflect movements into jobs by parents-particularly mothers, who in prior decades would have remained at home. This increase in market work has raised incomes for children in the typical two-parent family but not for those in lone-parent households. Time use data from 1975 and 2003-2008 reveal that working parents spend less time engaged in primary childcare than their counterparts without jobs but more than employed peers in previous cohorts. Analysis of 2004 work schedule data suggests that non-daytime work provides an alternative method of coordinating employment schedules for some dual-earner families.

  9. Parental Involvement, Child Temperament, and Parents’ Work Hours: Differential Relations for Mothers and Fathers

    PubMed Central

    Brown, Geoffrey L.; McBride, Brent A.; Bost, Kelly K.; Shin, Nana

    2014-01-01

    This study examined how child temperament was related to parents’ time spent accessible to and interacting with their 2-year-olds. Bivariate analyses indicated that both fathers and mothers spent more time with temperamentally challenging children than easier children on workdays, but fathers spent less time with challenging children than easier children on non-workdays. After accounting for work hours, some associations between temperament and fathers’ workday involvement dropped to non-significance. For fathers, work hours also moderated the relation between irregular temperament and workday play. For mothers, work hours moderated the relation between both difficult and irregular temperament and workday interaction. Mothers also spent more time with girls (but not boys) who were temperamentally irregular. Results speak to the influence of child temperament on parenting behavior, and the differential construction of parenting roles as a function of child characteristics and patterns of work. PMID:25960588

  10. Parental Involvement, Child Temperament, and Parents' Work Hours: Differential Relations for Mothers and Fathers.

    PubMed

    Brown, Geoffrey L; McBride, Brent A; Bost, Kelly K; Shin, Nana

    2011-01-01

    This study examined how child temperament was related to parents' time spent accessible to and interacting with their 2-year-olds. Bivariate analyses indicated that both fathers and mothers spent more time with temperamentally challenging children than easier children on workdays, but fathers spent less time with challenging children than easier children on non-workdays. After accounting for work hours, some associations between temperament and fathers' workday involvement dropped to non-significance. For fathers, work hours also moderated the relation between irregular temperament and workday play. For mothers, work hours moderated the relation between both difficult and irregular temperament and workday interaction. Mothers also spent more time with girls (but not boys) who were temperamentally irregular. Results speak to the influence of child temperament on parenting behavior, and the differential construction of parenting roles as a function of child characteristics and patterns of work.

  11. Families in a High-Tech Age: Technology Usage Patterns, Work and Family Correlates, and Gender

    ERIC Educational Resources Information Center

    Chesley, Noelle

    2006-01-01

    This study analyzes a couple-level ("N" = 581), longitudinal data set of employees to provide evidence about technology use over time, the factors that predict use, and the potential for a spouse to influence an individual's use. Although longitudinal usage patterns suggest a trend toward adoption and use of e-mail, the Internet, cell phones, and…

  12. Integrated Warfighter Biodefense Program (IWBP)

    DTIC Science & Technology

    2011-05-26

    empower the non-statistical subject matter expert to rapidly obtain insight into their data for discovery, forecasting and decision making. LeapWorks...Support for Time Series Pattern discovery in temporal data environments is important for many forecasting types of applications. For example, does the...as well as the forecasting horizon for the purposes of patterns discovery. Beta Testing During the period of performance for this report

  13. Family Patterns of Gender Role Attitudes

    PubMed Central

    Marks, Jaime; Bun, Lam Chun; McHale, Susan M.

    2012-01-01

    Study goals were to identify family patterns of gender role attitudes, to examine the conditions under which these patterns emerged, and to assess the implications of gender attitude patterns for family conflict. Participants were mothers, fathers, and first- and second-born adolescents from 358 White, working and middle-class US families. Results of cluster analysis revealed three gender role attitude patterns: egalitarian parents and children, traditional parents and children, and a divergent pattern, with parents more traditional and children more egalitarian. Mixed-model ANOVAs indicated that these family patterns were related to socioeconomic status, parents' time spent in gendered household tasks and with children, and the gender constellation of the sibling dyad. The traditional family group reported the most family conflict. PMID:22308059

  14. Associations between physical activity patterns and dietary patterns in a representative sample of Polish girls aged 13-21 years: a cross-sectional study (GEBaHealth Project).

    PubMed

    Wadolowska, Lidia; Kowalkowska, Joanna; Lonnie, Marta; Czarnocinska, Jolanta; Jezewska-Zychowicz, Marzena; Babicz-Zielinska, Ewa

    2016-08-02

    Similar to other countries, trends of decreasing levels of physical activity (PA) and an increasing prevalence of unhealthy dietary patterns are observed among girls in Poland. Better understanding of potentially inter-related behaviours within this population can help to design tailored interventions. The purpose of this study was to determine associations between PA patterns and dietary patterns in a representative sample of Polish girls. Girls aged 13-21 years (n = 1107) were randomly selected for the study. PA was assessed using International Physical Activity Questionnaire - Long (IPAQ-L). Dietary data were collected with food frequency questionnaires. PA patterns and dietary patterns were drawn separately by Principal Component Analysis (PCA). Logistic regression was used to find the associations between PA patterns and dietary patterns. Four major PA patterns ('School/work activity', 'Active recreation', 'Yard activity' and 'Walking and domestic activity') and four dietary patterns ('Traditional Polish', 'Fruit & vegetables', 'Fast food & sweets' and 'Dairy & fats') were identified. Level of PA was the highest in the upper tertile of 'School/work activity' pattern (mean 1372.2 MET-minutes/week, 95 % Confidence Intervals [CI]: 1285.9-1458.5). Girls in upper tertiles of 'Yard activity', 'Active recreation' and 'School/work activity' patterns had significantly higher chances of being in the upper tertile of the 'Fruit and vegetables' dietary pattern (odds ratio [OR] 2.17, 95 % CI: 1.50-3.14, p < 0.0001; OR 2.02, 95 % CI: 1.41-2.91; p < 0.001 and OR 1.76, 95 % CI: 1.24-2.51, p < 0.01 respectively; all adjusted for confounders) in comparison to bottom tertiles. Weak, but significant inverse associations were found between upper tertiles of 'Active recreation' and 'Yard activity' patterns and unhealthy dietary patterns. We found associations between PA patterns and dietary patterns in the population of Polish girls. Girls with the highest adherence to the 'School/work activity' pattern had the highest levels of PA and presented pro-healthy dietary behaviours. School should be recognised as potentially efficient and important setting to maximise girls' PA potential. The after-school time is the area that should also be targeted to increase daily PA or to at least sustain the level of PA after completing education.

  15. Developmental patterns and parental correlates of youth leisure-time physical activity.

    PubMed

    Lam, Chun Bun; McHale, Susan M

    2015-02-01

    This study examined the developmental patterns and parental correlates of youth leisure-time physical activity from middle childhood through adolescence. On 5 occasions across 7 years, fathers, mothers, and children who were first- and second born from 201 European American, working- and middle-class families participated in home and multiple nightly phone interviews. Multilevel modeling revealed that, controlling for family socioeconomic status, neighborhood characteristics, and youth overweight status and physical health, leisure-time physical activity increased during middle childhood and declined across adolescence, and the decline was more pronounced for girls than for boys. Moreover, controlling for time-varying, parental work hours and youth interest in sports and outdoor activities, on occasions when fathers and mothers spent proportionally more time on these activities with youth than usual, youth also spent more total time on these activities than usual. The within-person association between mother-youth joint involvement and youth's total involvement in leisure-time physical activity reached statistical significance at the transition to adolescence, and became stronger over time. Findings highlight the importance of maintaining adolescents', especially girls', physical activity levels and targeting both fathers' and mothers' involvement to promote youth's physical activity. PsycINFO Database Record (c) 2015 APA, all rights reserved.

  16. Coordination patterns related to high clinical performance in a simulated anesthetic crisis.

    PubMed

    Manser, Tanja; Harrison, Thomas Kyle; Gaba, David M; Howard, Steven K

    2009-05-01

    Teamwork is an integral component in the delivery of safe patient care. Several studies highlight the importance of effective teamwork and the need for teams to respond dynamically to changing task requirements, for example, during crisis situations. In this study, we address one of the many facets of "effective teamwork" in medical teams by investigating coordination patterns related to high performance in the management of a simulated malignant hyperthermia (MH) scenario. We hypothesized that (a) anesthesia crews dynamically adapt their work and coordination patterns to the occurrence of a simulated MH crisis and that (b) crews with higher clinical performance scores (based on a time-based scoring system for critical MH treatment steps) exhibit different coordination patterns. This observational study investigated differences in work and coordination patterns of 24 two-person anesthesia crews in a simulated MH scenario. Clinical and coordination behavior were coded using a structured observation system consisting of 36 mutually exclusive observation categories for clinical activities, coordination activities, teaching, and other communication. Clinical performance scores for treating the simulated episode of MH were calculated using a time-based scoring system for critical treatment steps. Coordination patterns in response to the occurrence of a crisis situation were analyzed using multivariate analysis of variance and the relationship between coordination patterns and clinical performance was investigated using hierarchical regression analyses. Qualitative analyses of the three highest and lowest performing crews were conducted to complement the quantitative analysis. First, a multivariate analysis of variance revealed statistically significant changes in the proportion of time spent on clinical and coordination activities once the MH crisis was declared (F [5,19] = 162.81, P < 0.001, eta(p)(2) = 0.98). Second, hierarchical regression analyses controlling for the effects of cognitive aid use showed that higher performing anesthesia crews exhibit statistically significant less task distribution (beta = -0.539, P < 0.01) and significantly more situation assessment (beta = 0.569, P < 0.05). Additional qualitative video analysis revealed, for example, that lower scoring crews were more likely to split into subcrews (i.e., both anesthesiologists worked with other members of the perioperative team without maintaining a shared plan among the two-person anesthesia crew). Our results of the relationship of coordination patterns and clinical performance will inform future research on adaptive coordination in medical teams and support the development of specific training to improve team coordination and performance.

  17. Safety of working patterns among UK neuroradiologists: what can we learn from the aviation industry and cognitive science?

    PubMed

    Reicher, John; Currie, Stuart; Birchall, Daniel

    2018-04-01

    As the volume and complexity of imaging in the UK continues to rise, there is pressure on radiologists to spend increasing lengths of time reporting to cope with the growing workload. However, there is limited guidance for radiologists about structuring the working day to strike the necessary balance between achieving satisfactory reporting volume and maintaining quality and safety. We surveyed 86 neuroradiologists (receiving 59 responses), regarding time spent reporting, frequency and duration of work breaks, and break activities. Our results demonstrate that some neuroradiologists report for up to 12 h a day and for 4 h before taking a break. Mean duration of breaks is less than 15 min and these often consist of computer screen-based or cognitively demanding tasks. Many areas of medicine have looked to the aviation industry to develop improvements in safety through regulated, standardised practices. There are parallels between the work of air traffic controllers (ATCs) and radiologists. We review the legislation that controls the working hours of UK ATCs to minimise fatigue-related errors, and its scientific basis. We also consider the vigilance decrement, a concept in cognitive science which describes the reduction in performance with increasing time-on-task. We conclude that, in comparison with ATCs, work patterns among radiologists are poorly standardised and potentially dangerous. Evidence suggests that placing limits on reporting time and minimum break duration, as well as ensuring appropriate break activities, can benefit reporting quality. It is imperative that radiologists and managers heed these lessons, to improve standards and protect patients from error.

  18. A new typology of work schedules: Evidence from a cross-sectional study among nurses working in residential elder care.

    PubMed

    Peters, V; de Rijk, A; Engels, J; Heerkens, Y; Nijhuis, F

    2016-04-07

    Work schedules contribute substantially to the health and well-being of nurses. Too broad typologies are used in research that do not meet the current variety in work schedules. To develop a new typology for nurses' work schedules based on five requirements and to validate the typology. This study is based on a questionnaire returned by 498 nurses (response 51%) including questions regarding nurses' work schedule, socio-demographic, and family characteristics and their appraisal of the work schedule. Frequencies of the different schedules were computed to determine the typology. To validate the typology, differences between the types were tested with ANOVAs, Chi2 and Kruskal-Wallis tests. Five main types can be distinguished based on predetermined requirements and frequencies, namely: (1) fixed early shift, (2) rotating two shift pattern without night shift, (3) rotating three shift pattern, (4) fixed and rotating two shift pattern including night shift, and (5) fixed normal day or afternoon shifts. Nurses in these types of work schedule differed significantly with respect to hours worked, days off between shifts, age, education, years in the job, commuting time, contribution to household income, satisfaction with work schedule and work schedule control. Especially nurses with type 3 schedules differed from other types. A typology of five main types of work schedules is proposed. Content validity of the typology is sufficient and the new typology seems useful for research on work-related aspects of nursing.

  19. How much time do nurses have for patients? a longitudinal study quantifying hospital nurses' patterns of task time distribution and interactions with health professionals

    PubMed Central

    2011-01-01

    Background Time nurses spend with patients is associated with improved patient outcomes, reduced errors, and patient and nurse satisfaction. Few studies have measured how nurses distribute their time across tasks. We aimed to quantify how nurses distribute their time across tasks, with patients, in individual tasks, and engagement with other health care providers; and how work patterns changed over a two year period. Methods Prospective observational study of 57 nurses for 191.3 hours (109.8 hours in 2005/2006 and 81.5 in 2008), on two wards in a teaching hospital in Australia. The validated Work Observation Method by Activity Timing (WOMBAT) method was applied. Proportions of time in 10 categories of work, average time per task, time with patients and others, information tools used, and rates of interruptions and multi-tasking were calculated. Results Nurses spent 37.0%[95%CI: 34.5, 39.3] of their time with patients, which did not change in year 3 [35.7%; 95%CI: 33.3, 38.0]. Direct care, indirect care, medication tasks and professional communication together consumed 76.4% of nurses' time in year 1 and 81.0% in year 3. Time on direct and indirect care increased significantly (respectively 20.4% to 24.8%, P < 0.01;13.0% to 16.1%, P < 0.01). Proportion of time on medication tasks (19.0%) did not change. Time in professional communication declined (24.0% to 19.2%, P < 0.05). Nurses completed an average of 72.3 tasks per hour, with a mean task length of 55 seconds. Interruptions arose at an average rate of two per hour, but medication tasks incurred 27% of all interruptions. In 25% of medication tasks nurses multi-tasked. Between years 1 and 3 nurses spent more time alone, from 27.5%[95%CI 24.5, 30.6] to 39.4%[34.9, 43.9]. Time with health professionals other than nurses was low and did not change. Conclusions Nurses spent around 37% of their time with patients which did not change. Work patterns were increasingly fragmented with rapid changes between tasks of short length. Interruptions were modest but their substantial over-representation among medication tasks raises potential safety concerns. There was no evidence of an increase in team-based, multi-disciplinary care. Over time nurses spent significantly less time talking with colleagues and more time alone. PMID:22111656

  20. Casualisation and the Adult Education Labour Market--An Industry in Crisis?

    ERIC Educational Resources Information Center

    Childs, Merilyn

    2000-01-01

    A 4-year study of 70 adult educators in the vocational training sector showed that they had diverse work patterns, with increasing numbers in casual, contractual, or part-time work. Employee flexibility was rarely rewarded or reciprocated by employers. Wage polarization increased, and a view was emerging that casualization was inevitable. (SK)

  1. Work Values Evolution in a Baccalaureate Student Nurse Population

    ERIC Educational Resources Information Center

    Dietrich, Marie C.

    1977-01-01

    Differences related to degree aspiration, desired nursing career specialty, and other nursing-related biographical variables were found among the four classes of a sample of 408 full-time non-RN female subjects in a baccalaureate nursing program. These differences were associated with shifts in the work values patterns of the subjects. (Author)

  2. Differences in time use and activity patterns when adding a second job: implications for health and safety in the United States.

    PubMed

    Marucci-Wellman, Helen R; Lin, Tin-Chi; Willetts, Joanna L; Brennan, Melanye J; Verma, Santosh K

    2014-08-01

    We compared work and lifestyle activities for workers who work in 1 job with those who work in multiple jobs during a 1-week period. We used information from the 2003-2011 American Time Use Survey to classify workers into 6 work groups based on whether they were a single (SJH) or multiple (MJH) job holder and whether they worked their primary, other, multiple, or no job on the diary day. The MJHs often worked 2 part-time jobs (20%), long weekly hours (27% worked 60+ hours), and on weekends. The MJHs working multiple jobs on the diary day averaged more than 2 additional work hours (2.25 weekday, 2.75 weekend day; P < .05), odd hours (more often between 5 pm and 7 am), with more work travel time (10 minutes weekday, 9 minutes weekend day; P < .05) and less sleep (-45 minutes weekday, -62 minutes weekend day; P < .05) and time for other household (P < .05) and leisure (P < .05) activities than SJHs. Because of long work hours, long daily commutes, multiple shifts, and less sleep and leisure time, MJHs may be at heightened risk of fatigue and injury.

  3. Differences in Time Use and Activity Patterns When Adding a Second Job: Implications for Health and Safety in the United States

    PubMed Central

    Willetts, Joanna L.; Brennan, Melanye J.; Verma, Santosh K.

    2014-01-01

    Objectives. We compared work and lifestyle activities for workers who work in 1 job with those who work in multiple jobs during a 1-week period. Methods. We used information from the 2003–2011 American Time Use Survey to classify workers into 6 work groups based on whether they were a single (SJH) or multiple (MJH) job holder and whether they worked their primary, other, multiple, or no job on the diary day. Results. The MJHs often worked 2 part-time jobs (20%), long weekly hours (27% worked 60+ hours), and on weekends. The MJHs working multiple jobs on the diary day averaged more than 2 additional work hours (2.25 weekday, 2.75 weekend day; P < .05), odd hours (more often between 5 pm and 7 am), with more work travel time (10 minutes weekday, 9 minutes weekend day; P < .05) and less sleep (–45 minutes weekday, −62 minutes weekend day; P < .05) and time for other household (P < .05) and leisure (P < .05) activities than SJHs. Conclusions. Because of long work hours, long daily commutes, multiple shifts, and less sleep and leisure time, MJHs may be at heightened risk of fatigue and injury. PMID:24922135

  4. A Comparison of Work Health and Safety Incidents and Injuries in Part-Time and Full-Time Australian Army Personnel.

    PubMed

    McDonald, Dylan; Orr, Robin M; Pope, Rodney

    2016-11-01

     Part-time personnel are an integral part of the Australian Army. With operational deployments increasing, it is essential that medical teams identify the patterns of injuries sustained by part-time personnel in order to mitigate the risks of injury and optimize deployability.  To compare the patterns of reported work health and safety incidents and injuries in part-time and full-time Australian Army personnel.  Retrospective cohort study.  The Australian Army.  Australian Army Reserve and Australian regular Army populations, July 1, 2012, through June 30, 2014.  Proportions of reported work health and safety incidents that resulted in injuries among Army Reserve and regular Army personnel and specifically the (a) body locations affected by incidents, (b) nature of resulting injuries, (c) injury mechanisms, and (d) activities being performed when the incidents occurred.  Over 2 years, 15 065 work health and safety incidents and 11 263 injuries were reported in Army Reserve and regular Army populations combined. In the Army Reserve population, 85% of reported incidents were classified as involving minor personal injuries; 4% involved a serious personal injury. In the regular Army population, 68% of reported incidents involved a minor personal injury; 5% involved a serious personal injury. Substantially lower proportions of Army reservist incidents involved sports, whereas substantially higher proportions were associated with combat training, manual handling, and patrolling when compared with regular Army incidents.  Army reservists had a higher proportion of injuries from Army work-related activities than did regular Army soldiers. Proportions of incidents arising from combat tasks and manual handling were higher in the Army Reserve. Understanding the sources of injuries will allow the medical teams to implement injury-mitigation strategies.

  5. A Comparison of Work Health and Safety Incidents and Injuries in Part-Time and Full-Time Australian Army Personnel

    PubMed Central

    McDonald, Dylan; Orr, Robin M.; Pope, Rodney

    2016-01-01

    Context: Part-time personnel are an integral part of the Australian Army. With operational deployments increasing, it is essential that medical teams identify the patterns of injuries sustained by part-time personnel in order to mitigate the risks of injury and optimize deployability. Objective: To compare the patterns of reported work health and safety incidents and injuries in part-time and full-time Australian Army personnel. Design: Retrospective cohort study. Setting: The Australian Army. Patients or Other Participants: Australian Army Reserve and Australian regular Army populations, July 1, 2012, through June 30, 2014. Main Outcome Measure(s): Proportions of reported work health and safety incidents that resulted in injuries among Army Reserve and regular Army personnel and specifically the (a) body locations affected by incidents, (b) nature of resulting injuries, (c) injury mechanisms, and (d) activities being performed when the incidents occurred. Results: Over 2 years, 15 065 work health and safety incidents and 11 263 injuries were reported in Army Reserve and regular Army populations combined. In the Army Reserve population, 85% of reported incidents were classified as involving minor personal injuries; 4% involved a serious personal injury. In the regular Army population, 68% of reported incidents involved a minor personal injury; 5% involved a serious personal injury. Substantially lower proportions of Army reservist incidents involved sports, whereas substantially higher proportions were associated with combat training, manual handling, and patrolling when compared with regular Army incidents. Conclusions: Army reservists had a higher proportion of injuries from Army work-related activities than did regular Army soldiers. Proportions of incidents arising from combat tasks and manual handling were higher in the Army Reserve. Understanding the sources of injuries will allow the medical teams to implement injury-mitigation strategies. PMID:27710093

  6. Has Ebbinghaus Decayed with Time? The Growth of Recall (Hypermnesia) over Days

    ERIC Educational Resources Information Center

    Erdelyi, Matthew Hugh; Kleinbard, Jeff

    1978-01-01

    Recent laboratory work on the recall of pictures has produced a pattern suggesting that memory for certain classes of stimuli may be hypermnesiac rather than amnesiac (Ebbinghaus, 1885/1964), increasing over time and recall attempts. This research tries to determine the magnitude of memory growth over significant time intervals, e.g., a week…

  7. Mouse Activity across Time Scales: Fractal Scenarios

    PubMed Central

    Lima, G. Z. dos Santos; Lobão-Soares, B.; do Nascimento, G. C.; França, Arthur S. C.; Muratori, L.; Ribeiro, S.; Corso, G.

    2014-01-01

    In this work we devise a classification of mouse activity patterns based on accelerometer data using Detrended Fluctuation Analysis. We use two characteristic mouse behavioural states as benchmarks in this study: waking in free activity and slow-wave sleep (SWS). In both situations we find roughly the same pattern: for short time intervals we observe high correlation in activity - a typical 1/f complex pattern - while for large time intervals there is anti-correlation. High correlation of short intervals ( to : waking state and to : SWS) is related to highly coordinated muscle activity. In the waking state we associate high correlation both to muscle activity and to mouse stereotyped movements (grooming, waking, etc.). On the other side, the observed anti-correlation over large time scales ( to : waking state and to : SWS) during SWS appears related to a feedback autonomic response. The transition from correlated regime at short scales to an anti-correlated regime at large scales during SWS is given by the respiratory cycle interval, while during the waking state this transition occurs at the time scale corresponding to the duration of the stereotyped mouse movements. Furthermore, we find that the waking state is characterized by longer time scales than SWS and by a softer transition from correlation to anti-correlation. Moreover, this soft transition in the waking state encompass a behavioural time scale window that gives rise to a multifractal pattern. We believe that the observed multifractality in mouse activity is formed by the integration of several stereotyped movements each one with a characteristic time correlation. Finally, we compare scaling properties of body acceleration fluctuation time series during sleep and wake periods for healthy mice. Interestingly, differences between sleep and wake in the scaling exponents are comparable to previous works regarding human heartbeat. Complementarily, the nature of these sleep-wake dynamics could lead to a better understanding of neuroautonomic regulation mechanisms. PMID:25275515

  8. Job satisfaction, work-related stress and intentions to quit of Scottish GPS.

    PubMed

    Simoens, S; Scott, A; Sibbald, B

    2002-08-01

    Job satisfaction and work-related stress influence physician retention, turnover, and patient satisfaction. This study purports to elicit the views of Scottish GPs on job satisfaction, stress, intentions to quit, and to examine any patterns by demographic, job, and practice characteristics. A descriptive, cross-sectional study was undertaken by postal questionnaire on a random sample of 1,000 GP principals, 359 GP non-principals, and 62 PMS GPs. The response rate was 56%. GPs were most satisfied with their colleagues, variety in the job, and amount of responsibility given. The most frequently mentioned sources of job stress were increasing workloads, paperwork, insufficient time to do justice to the job, increased and inappropriate demands from patients. White, female, young (under 40 years) and old (55 years and over) GP non-principals and PMS GPs who work less than 50 hours per week as a GP were more likely to be satisfied with their job and reported lower levels of stress. GP participation in the workforce could be promoted by introducing more flexible working patterns (e.g. part-time work), by expanding the scope of contractual arrangements, and by making patient expectations more realistic by clearly communicating what the role of a GP actually encompasses.

  9. Musculoskeletal injuries among hospital patient care staff before and after implementation of patient lift and transfer equipment.

    PubMed

    Schoenfisch, Ashley L; Lipscomb, Hester J; Pompeii, Lisa A; Myers, Douglas J; Dement, John M

    2013-01-01

    Using an observational research design and robust surveillance data, we evaluated rates of musculoskeletal (MS) injuries, days away from work, and restricted work days among patient care staff at a medical center and community hospital in the United States over 13 years, during which time a "minimal manual lift" policy and mechanical lift equipment were implemented. Workers' compensation claims data were linked to human resources data to define outcomes of interest and person-time at risk to calculate rates. Poisson and negative binomial regression with lagging were used to compare outcome rates in different windows of time surrounding the intervention. Patterns of MS injuries associated with patient-handling were contrasted to patterns of other MS injuries that would not be affected by the use of mechanical lift equipment. At the medical center, no change in the patient-handling MS injury rate followed the intervention. A 44% decrease was observed at the community hospital. At both hospitals, the rate of days away declined immediately - before it was reasonable for the intervention to have been adopted. Institutional-level changes at the time of the intervention likely influenced observed results with findings only partially consistent with an intervention effect. Observational studies can be useful in assessing effectiveness of safety interventions in complex work environments. Such studies should consider the process of intervention implementation, the time needed for intervention adoption, and the dynamic nature of work environments.

  10. Part-time work among pediatricians expands.

    PubMed

    Cull, William L; O'Connor, Karen G; Olson, Lynn M

    2010-01-01

    The objective of this study was to track trends in part-time employment among pediatricians from 2000 to 2006 and to examine differences within subgroups of pediatricians. As part of the Periodic Survey of Fellows, national random samples of American Academy of Pediatrics members were surveyed in 2000, 2003, and 2006. These surveys shared questions concerning working part-time and other practice characteristics. Roughly 1600 pediatricians were included in each random sample. Totals of 812 (51%), 1020 (63%), and 1013 (62%) pediatricians completed the surveys in 2000, 2003, and 2006, respectively. Analyses were limited to nonretired, posttrainee pediatricians. The number of pediatricians who reported that they work part-time increased from 15% in 2000, to 20% in 2003, to 23% in 2006. The pattern of increased part-time work from 2000 to 2006 held for many subgroups, including men, women, pediatricians who were younger than 40 years, pediatricians who were aged >or=50 years, pediatricians who worked in an urban inner city, pediatricians who worked in suburban areas, general pediatricians, and subspecialist pediatricians. Those who were working part-time were more satisfied within their professional and personal activities. Part-time pediatricians worked on average 14.3 fewer hours per week in direct patient care. Increases in part-time work are apparent throughout pediatrics. The possible continued growth of part-time is an important trend within the field of pediatrics that will need to be monitored.

  11. A Week in the Life of Full-Time Office Workers: Work Day and Weekend Light Exposure in Summer and Winter

    PubMed Central

    Crowley, Stephanie J.; Molina, Thomas A.; Burgess, Helen J.

    2014-01-01

    Little is known about the light exposure in full-time office workers, who spend much of their workdays indoors. We examined the 24-hour light exposure patterns of 14 full-time office workers during a week in summer, and assessed their dim light melatonin onset (DLMO, a marker of circadian timing) at the end of the working week. Six workers repeated the study in winter. Season had little impact on the workers' schedules, as the timing of sleep, commute, and work did not vary by more than 30 minutes in the summer and winter. In both seasons, workers received significantly more morning light on workdays than weekends, due to earlier wake times and the morning commute. Evening light in the two hours before bedtime was consistently dim. The timing of the DLMO did not vary between season, and by the end of the working week, the workers slept at a normal circadian phase. PMID:25172304

  12. A method for assessing work productivity and flexibility in livestock farms.

    PubMed

    Hostiou, N; Dedieu, B

    2012-05-01

    Changes affecting livestock farming systems have made farm work a central concern for both the sector and for farmers themselves. Increased pressure on farms to be competitive and productive together with farmers' demand for greater autonomy, holidays or time to spend on private activities and the family converge to underline the two key dimensions of work - productivity and flexibility - required for the assessment of work organization. This paper proposes a method called the QuaeWork (QUAlification and Evaluation of Work in livestock farms) to assess work productivity and flexibility on a farm, and its use to identify how livestock management can contribute to work organization on dairy farms. The QuaeWork method was set up through an iterative process combining surveys conducted with farmers in two regions of France, discussions with different experts and literature review. The QuaeWork was applied on a sample of seven dairy farms in the southern Massif Central in France to identify patterns of how livestock management contributes to work organization. The QuaeWork was used to analyse work organization over the year through a systemic approach to the farm, integrating interactions between herd and land management, workforce composition, equipment facilities and combinations of activities through a characterization of 'who does what, when and for how long'. The criteria for assessing work productivity were work duration (routine work, seasonal work) and work efficiency (per livestock unit or hectare of utilized agricultural area). The criteria for assessing work flexibility were room for manoeuvre and adjustments to internal and external events. The three main patterns of livestock management practices to work organization were identified. In pattern-1, farmers used indoor stable feeding practices with delegated work, with moderate room for manoeuvre and efficiency. In pattern-3, farmers used simplified milking, reproduction and breeding practices to seasonalize work and make it efficient with consistent room for manoeuvre. The method suggests social sustainability criteria to assess work productivity and flexibility, which are important for making reasoned decisions on livestock farm changes, especially innovations. Researchers could usefully exploit the QuaeWork to integrate work objectives (productivity, flexibility) into technical and economic goals.

  13. Ginkobiloba extract improves working memory performance in middle-aged women: role of asymmetry of prefrontal cortex activity during a working memory task.

    PubMed

    Sakatani, Kaoru; Tanida, Masahiro; Hirao, Naoyasu; Takemura, Naohiro

    2014-01-01

    In order to clarify the mechanism through which extract of Ginkgo biloba leaves (EGb) improves cognitive function, we examined the effects of EGb on cerebral blood oxygenation in the prefrontal cortex (PFC) and on performance during a working memory task, using near-infrared spectrometry (NIRS). First, we evaluated differences in behavioral performance of the Sternberg working memory test (ST) and in the activation pattern of the PFC during ST between 15 young and 19 middle-aged healthy women. Then, we examined the effect of EGb (120 mg/day for 6 weeks) on ST performance and PFC activation pattern in the middle-aged group. The middle-aged group exhibited a longer reaction time (RT) in ST than the young group and showed a different PFC activation pattern during ST, i.e., the middle-aged group showed bilateral activation while the young group showed right-dominant activation. In the middle-aged group, administration of EGb for 6 weeks shortened the RT of ST and changed the PFC activation pattern to right-dominant, like that in the young group. The results indicate the PFC plays a role in the physiological cognitive function-enhancing effect of EGb. EGb might improve working memory function in middle-aged individuals by counteracting the occurrence of aging-related hemispheric asymmetry reduction.

  14. A Verification Method of Inter-Task Cooperation in Embedded Real-time Systems and its Evaluation

    NASA Astrophysics Data System (ADS)

    Yoshida, Toshio

    In software development process of embedded real-time systems, the design of the task cooperation process is very important. The cooperating process of such tasks is specified by task cooperation patterns. Adoption of unsuitable task cooperation patterns has fatal influence on system performance, quality, and extendibility. In order to prevent repetitive work caused by the shortage of task cooperation performance, it is necessary to verify task cooperation patterns in an early software development stage. However, it is very difficult to verify task cooperation patterns in an early software developing stage where task program codes are not completed yet. Therefore, we propose a verification method using task skeleton program codes and a real-time kernel that has a function of recording all events during software execution such as system calls issued by task program codes, external interrupts, and timer interrupt. In order to evaluate the proposed verification method, we applied it to the software development process of a mechatronics control system.

  15. Useful Spanish for Medical and Hospital Personnel with a Bibliography on Hispanic Peoples in the United States.

    ERIC Educational Resources Information Center

    Cordasco, Francesco; Alvarez, Pablo Rivera

    The manual gives vocabulary and sentence patterns which are considered basic or essential to medical personnel who work with Spanish-speaking patients. In most instances, only one way is given to express an idea or to ask a question. Sentence patterns and vocabulary that should be made active are repeated many times. The manual includes (1)…

  16. A Brain System for Auditory Working Memory.

    PubMed

    Kumar, Sukhbinder; Joseph, Sabine; Gander, Phillip E; Barascud, Nicolas; Halpern, Andrea R; Griffiths, Timothy D

    2016-04-20

    The brain basis for auditory working memory, the process of actively maintaining sounds in memory over short periods of time, is controversial. Using functional magnetic resonance imaging in human participants, we demonstrate that the maintenance of single tones in memory is associated with activation in auditory cortex. In addition, sustained activation was observed in hippocampus and inferior frontal gyrus. Multivoxel pattern analysis showed that patterns of activity in auditory cortex and left inferior frontal gyrus distinguished the tone that was maintained in memory. Functional connectivity during maintenance was demonstrated between auditory cortex and both the hippocampus and inferior frontal cortex. The data support a system for auditory working memory based on the maintenance of sound-specific representations in auditory cortex by projections from higher-order areas, including the hippocampus and frontal cortex. In this work, we demonstrate a system for maintaining sound in working memory based on activity in auditory cortex, hippocampus, and frontal cortex, and functional connectivity among them. Specifically, our work makes three advances from the previous work. First, we robustly demonstrate hippocampal involvement in all phases of auditory working memory (encoding, maintenance, and retrieval): the role of hippocampus in working memory is controversial. Second, using a pattern classification technique, we show that activity in the auditory cortex and inferior frontal gyrus is specific to the maintained tones in working memory. Third, we show long-range connectivity of auditory cortex to hippocampus and frontal cortex, which may be responsible for keeping such representations active during working memory maintenance. Copyright © 2016 Kumar et al.

  17. Dynamic search and working memory in social recall.

    PubMed

    Hills, Thomas T; Pachur, Thorsten

    2012-01-01

    What are the mechanisms underlying search in social memory (e.g., remembering the people one knows)? Do the search mechanisms involve dynamic local-to-global transitions similar to semantic search, and are these transitions governed by the general control of attention, associated with working memory span? To find out, we asked participants to recall individuals from their personal social networks and measured each participant's working memory capacity. Additionally, participants provided social-category and contact-frequency information about the recalled individuals as well as information about the social proximity among the recalled individuals. On the basis of these data, we tested various computational models of memory search regarding their ability to account for the patterns in which participants recalled from social memory. Although recall patterns showed clustering based on social categories, models assuming dynamic transitions between representations cued by social proximity and frequency information predicted participants' recall patterns best-no additional explanatory power was gained from social-category information. Moreover, individual differences in the time between transitions were positively correlated with differences in working memory capacity. These results highlight the role of social proximity in structuring social memory and elucidate the role of working memory for maintaining search criteria during search within that structure.

  18. Recent variations in seasonality of temperature and precipitation in Canada, 1976-95

    NASA Astrophysics Data System (ADS)

    Whitfield, Paul H.; Bodtker, Karin; Cannon, Alex J.

    2002-11-01

    A previously reported analysis of rehabilitated monthly temperature and precipitation time series for several hundred stations across Canada showed generally spatially coherent patterns of variation between two decades (1976-85 and 1986-95). The present work expands that analysis to finer time scales and a greater number of stations. We demonstrate how the finer temporal resolution, at 5 day or 11 day intervals, increases the separation between clusters of recent variations in seasonal patterns of temperature and precipitation. We also expand the analysis by increasing the number of stations from only rehabilitated monthly data sets to rehabilitated daily sets, then to approximately 1500 daily observation stations. This increases the spatial density of data and allows a finer spatial resolution of patterns between the two decades. We also examine the success of clustering partial records, i.e. sites where the data record is incomplete. The intent of this study was to be consistent with previous work and explore how greater temporal and spatial detail in the climate data affects the resolution of patterns of recent climate variations. The variations we report for temperature and precipitation are taking place at different temporal and spatial scales. Further, the spatial patterns are much broader than local climate regions and ecozones, indicating that the differences observed may be the result of variations in atmospheric circulation.

  19. The Growing Diversity of Work Schedules.

    ERIC Educational Resources Information Center

    Smith, Shirley J.

    1986-01-01

    The author highlights the predominance of the five-day, 40-hour workweek. Although finding little change in recent years in the proportion of workers on 40-hour schedules, Smith notes that there have been some changes in work patterns, with a still small but growing group of workers on "compressed" full-time weeks of less than five days.…

  20. EWTD compliance amongst Anaesthesia trainees in Ireland.

    PubMed

    Brohan, J; Moore, D

    2017-02-01

    The implications of the EWTD include a limit of 48 h working week and 11 consecutive hours rest every 24 h. This survey was designed to assess EWTD compliance over designated 1-week and 1-month periods amongst College of Anaesthesetists of Ireland (CAI) trainees and non-training Anaesthesia NCHDs. The two key elements of EWTD compliance were assessed; the compliance to a 48 h working week, and a minimizing of shift duration to 24 h. Existence of protected training time and teaching time were also assessed. This survey was completed by 191 Anaesthesia NCHDs, including 151 responses from CAI trainees; 75 % response rate from CAI trainees. 71 % of respondents worked in excess of 48 h. 37 % of respondents reported to have worked a shift >24 h duration. The average hours worked was 66 h (range 48.5-103 h). Our figures are a contrast to the reported figures in the HSE "Performance Assurance Report". 49 % of respondents reported a change in their working patterns to facilitate EWTD compliance. There appears to be a negative impact on training however, with 68 % respondents missing departmental teaching sessions and 30 % not receiving protected training time. 33 % of respondents were not in favour of full EWTD compliance. As work patterns change, it is vital to ensure that training is not compromised. Previous reports have recommended an increase in consultant numbers, which has yet to be achieved. This may provide a solution to allow service provision, NCHD training and EWTD compliance amongst NCHDs.

  1. The Influence of Unpaid Work on the Transition Out of Full-Time Paid Work

    PubMed Central

    Carr, Dawn C.

    2013-01-01

    Purpose: Continued employment after retirement and engagement in unpaid work are both important ways of diminishing the negative economic effects of the retirement of baby boomer cohorts on society. Little research, however, examines the relationship between paid and unpaid work at the transition from full-time work. Using a resource perspective framework this study examines how engagement in unpaid work prior to and at the transition from full-time work influences whether individuals partially or fully retire. Design and Methods: This study used a sample of 2,236 Americans between the ages 50 and 68, who were interviewed between 1998 and 2008. Logistic regression was used to estimate transitioning into partial retirement (relative to full retirement) after leaving full-time work. Results: We found that the odds of transitioning into part-time work were increased by continuous volunteering (78%) and reduced by starting parental (84%), grandchild (41%), and spousal (90%) caregiving and unaffected by all other patterns of engagement in unpaid work. Implications: Our findings suggest that volunteering is complementary with a transition to part-time work, and starting a new caregiving role at this transitioncreates a barrier to continued employment. In order to provide workers the opportunity to engage in the work force longer at the brink of retirement, it may be necessary to increase the support mechanisms for those who experience new caregiving responsibilities. PMID:22859436

  2. Job Sharing: An Alternative to Traditional Employment Patterns. ERS Information Aid.

    ERIC Educational Resources Information Center

    Block, Alan W.

    In the face of declining enrollments and widespread reductions-in-force in school systems, job sharing can provide part-time positions for persons unable to work full-time and can allow some individuals to maintain their positions on a part-time basis as an alternative to being laid off. Job sharing can also benefit school systems by increasing…

  3. Full-Time Employed Students as University Consumers--Consequences and Triggers of Marketisation of Higher Education

    ERIC Educational Resources Information Center

    Mägi, Eve; Jaakson, Krista; Aidla, Anne; Kirss, Laura; Reino, Anne

    2012-01-01

    This article draws on a qualitative study of student employment patterns among students who both study and work full-time. In the study, 17 employed bachelor students at state-commissioned study places in three Estonian universities, 12 lecturers from the same universities, and 13 employers supervising those full-time students, were interviewed.…

  4. Combinatorial pattern discovery approach for the folding trajectory analysis of a beta-hairpin.

    PubMed

    Parida, Laxmi; Zhou, Ruhong

    2005-06-01

    The study of protein folding mechanisms continues to be one of the most challenging problems in computational biology. Currently, the protein folding mechanism is often characterized by calculating the free energy landscape versus various reaction coordinates, such as the fraction of native contacts, the radius of gyration, RMSD from the native structure, and so on. In this paper, we present a combinatorial pattern discovery approach toward understanding the global state changes during the folding process. This is a first step toward an unsupervised (and perhaps eventually automated) approach toward identification of global states. The approach is based on computing biclusters (or patterned clusters)-each cluster is a combination of various reaction coordinates, and its signature pattern facilitates the computation of the Z-score for the cluster. For this discovery process, we present an algorithm of time complexity c in RO((N + nm) log n), where N is the size of the output patterns and (n x m) is the size of the input with n time frames and m reaction coordinates. To date, this is the best time complexity for this problem. We next apply this to a beta-hairpin folding trajectory and demonstrate that this approach extracts crucial information about protein folding intermediate states and mechanism. We make three observations about the approach: (1) The method recovers states previously obtained by visually analyzing free energy surfaces. (2) It also succeeds in extracting meaningful patterns and structures that had been overlooked in previous works, which provides a better understanding of the folding mechanism of the beta-hairpin. These new patterns also interconnect various states in existing free energy surfaces versus different reaction coordinates. (3) The approach does not require calculating the free energy values, yet it offers an analysis comparable to, and sometimes better than, the methods that use free energy landscapes, thus validating the choice of reaction coordinates. (An abstract version of this work was presented at the 2005 Asia Pacific Bioinformatics Conference [1].).

  5. Travel patterns during pregnancy: comparison between Global Positioning System (GPS) tracking and questionnaire data.

    PubMed

    Wu, Jun; Jiang, Chengsheng; Jaimes, Guillermo; Bartell, Scott; Dang, Andy; Baker, Dean; Delfino, Ralph J

    2013-10-09

    Maternal exposures to traffic-related air pollution have been associated with adverse pregnancy outcomes. Exposures to traffic-related air pollutants are strongly influenced by time spent near traffic. However, little is known about women's travel activities during pregnancy and whether questionnaire-based data can provide reliable information on travel patterns during pregnancy. Examine women's in-vehicle travel behavior during pregnancy and examine the difference in travel data collected by questionnaire and global positioning system (GPS) and their potential for exposure error. We measured work-related travel patterns in 56 pregnant women using a questionnaire and one-week GPS tracking three times during pregnancy (<20 weeks, 20-30 weeks, and >30 weeks of gestation). We compared self-reported activities with GPS-derived trip distance and duration, and examined potentially influential factors that may contribute to differences. We also described in-vehicle travel behavior by pregnancy periods and influences of demographic and personal factors on daily travel times. Finally, we estimated personal exposure to particle-bound polycyclic aromatic hydrocarbon (PB-PAH) and examined the magnitude of exposure misclassification using self-reported vs. GPS travel data. Subjects overestimated both trip duration and trip distance compared to the GPS data. We observed moderately high correlations between self-reported and GPS-recorded travel distance (home to work trips: r = 0.88; work to home trips: r = 0.80). Better agreement was observed between the GPS and the self-reported travel time for home to work trips (r = 0.77) than work to home trips (r = 0.64). The subjects on average spent 69 and 93 minutes traveling in vehicles daily based on the GPS and self-reported data, respectively. Longer daily travel time was observed among participants in early pregnancy, and during certain pregnancy periods in women with higher education attainment, higher income, and no children. When comparing self-reported vs. GPS data, we found that estimated personal exposure to PB-PAH did not differ remarkably at the population level, but the difference was large at an individual level. Self-reported home-to-work data overestimated both trip duration and trip distance compared to GPS data. Significant differences in PAH exposure estimates were observed at individual level using self-reported vs. GPS data, which has important implications in air pollution epidemiological studies.

  6. Comparison of female and male graduates of southern Appalachian family practice residencies.

    PubMed

    Rosenfeld, J A; Zaborlik, P M

    1996-11-01

    One aim of Southern Appalachian family practice residencies is to produce graduates for surrounding physician-needy areas. Some evidence suggests that women are less likely to go to rural areas and that they practice differently than men. This study investigated the practice patterns and location of Appalachian family practice residency female and male graduates. Surveys were sent to graduates of seven family practice residencies from 1984 to 1994 in the Southern Appalachian area to determine practice patterns, locations, and reasons for choosing practices. Women were more likely than men to be single and not to have children. More women worked part-time. Women's and men's practice patterns and characteristics were similar except that women were more likely to provide prenatal care and do vaginal deliveries. Women in similar percentages practiced in small towns, and a greater percentage of women practiced in rural areas with populations of less than 2,500. Female family practice residency graduates from Appalachian residencies are fulfilling the purposes of their residencies as well as male graduates, although more of them are working part-time.

  7. Patterns of sedentary behavior in overweight and moderately obese users of the Catalan primary-health care system

    PubMed Central

    Beltran, Angela-Maria; Martín-Borràs, Carme; Lasaosa-Medina, Lourdes; Real, Jordi; Trujillo, José-Manuel; Solà-Gonfaus, Mercè; Puigdomenech, Elisa; Castillo-Ramos, Eva; Puig-Ribera, Anna; Giné-Garriga, Maria; Serra-Paya, Noemi; Rodriguez-Roca, Beatriz; Gascón-Catalán, Ana; Martín-Cantera, Carlos

    2018-01-01

    Background and objectives Prolonged sitting time (ST) has negative consequences on health. Changing this behavior is paramount in overweight/obese individuals because they are more sedentary than those with normal weight. The aim of the study was to establish the pattern of sedentary behavior and its relationship to health, socio-demographics, occupation, and education level in Catalan overweight/obese individuals. Methods A descriptive study was performed at 25 healthcare centers in Catalonia (Spain) with 464 overweight/moderately obese patients, aged25 to 65 years. Exclusion criteria were chronic diseases which contraindicated physical activity and language barriers. Face-to-face interviews were conducted to collect data on age, gender, educational level, social class, and marital status. Main outcome was ‘sitting time’ (collected by the Marshall questionnaire); chronic diseases and anthropometric measurements were registered. Results 464 patients, 58.4% women, mean age 51.9 years (SD 10.1), 76.1% married, 60% manual workers, and 48.7% had finished secondary education. Daily sitting time was 6.2 hours on working days (374 minutes/day, SD: 190), and about 6 hours on non-working ones (357 minutes/day, SD: 170). 50% of participants were sedentary ≥6 hours. The most frequent sedentary activities were: working/academic activities around 2 hours (128 minutes, SD: 183), followed by watching television, computer use, and commuting. Men sat longer than women (64 minutes more on working days and 54 minutes on non-working days), and individuals with office jobs (91 minutes),those with higher levels of education (42 minutes), and younger subjects (25 to 35 years) spent more time sitting. Conclusions In our study performed in overweight/moderately obese patients the mean sitting time was around 6 hours which was mainly spent doing work/academic activities and watching television. Men, office workers, individuals with higher education, and younger subjects had longer sitting time. Our results may help design interventions targeted at these sedentary patients to decrease sitting time. PMID:29370176

  8. Monitoring sedentary patterns in office employees: validity of an m-health tool (Walk@Work-App) for occupational health.

    PubMed

    Bort-Roig, Judit; Puig-Ribera, Anna; Contreras, Ruth S; Chirveches-Pérez, Emilia; Martori, Joan C; Gilson, Nicholas D; McKenna, Jim

    2017-09-15

    This study validated the Walk@Work-Application (W@W-App) for measuring occupational sitting and stepping. The W@W-App was installed on the smartphones of office-based employees (n=17; 10 women; 26±3 years). A prescribed 1-hour laboratory protocol plus two continuous hours of occupational free-living activities were performed. Intra-class correlation coefficients (ICC) compared mean differences of sitting time and step count measurements between the W@W-App and criterion measures (ActivPAL3TM and SW200Yamax Digi-Walker). During the protocol, agreement between self-paced walking (ICC=0.85) and active working tasks step counts (ICC=0.80) was good. The smallest median difference was for sitting time (1.5seconds). During free-living conditions, sitting time (ICC=0.99) and stepping (ICC=0.92) showed excellent agreement, with a difference of 0.5minutes and 18 steps respectively. The W@W-App provided valid measures for monitoring occupational sedentary patterns in real life conditions; a key issue for increasing awareness and changing occupational sedentariness. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  9. The downside of downtime: The prevalence and work pacing consequences of idle time at work.

    PubMed

    Brodsky, Andrew; Amabile, Teresa M

    2018-05-01

    Although both media commentary and academic research have focused much attention on the dilemma of employees being too busy, this paper presents evidence of the opposite phenomenon, in which employees do not have enough work to fill their time and are left with hours of meaningless idle time each week. We conducted six studies that examine the prevalence and work pacing consequences of involuntary idle time. In a nationally representative cross-occupational survey (Study 1), we found that idle time occurs frequently across all occupational categories; we estimate that employers in the United States pay roughly $100 billion in wages for time that employees spend idle. Studies 2a-3b experimentally demonstrate that there are also collateral consequences of idle time; when workers expect idle time following a task, their work pace declines and their task completion time increases. This decline reverses the well-documented deadline effect, producing a deadtime effect, whereby workers slow down as a task progresses. Our analyses of work pace patterns provide evidence for a time discounting mechanism: workers discount idle time when it is relatively distant, but act to avoid it increasingly as it becomes more proximate. Finally, Study 4 demonstrates that the expectation of being able to engage in leisure activities during posttask free time (e.g., surfing the Internet) can mitigate the collateral work pace losses due to idle time. Through examination and discussion of the effects of idle time at work, we broaden theory on work pacing. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  10. What Not To Do: Anti-patterns for Developing Scientific Workflow Software Components

    NASA Astrophysics Data System (ADS)

    Futrelle, J.; Maffei, A. R.; Sosik, H. M.; Gallager, S. M.; York, A.

    2013-12-01

    Scientific workflows promise to enable efficient scaling-up of researcher code to handle large datasets and workloads, as well as documentation of scientific processing via standardized provenance records, etc. Workflow systems and related frameworks for coordinating the execution of otherwise separate components are limited, however, in their ability to overcome software engineering design problems commonly encountered in pre-existing components, such as scripts developed externally by scientists in their laboratories. In practice, this often means that components must be rewritten or replaced in a time-consuming, expensive process. In the course of an extensive workflow development project involving large-scale oceanographic image processing, we have begun to identify and codify 'anti-patterns'--problematic design characteristics of software--that make components fit poorly into complex automated workflows. We have gone on to develop and document low-effort solutions and best practices that efficiently address the anti-patterns we have identified. The issues, solutions, and best practices can be used to evaluate and improve existing code, as well as guiding the development of new components. For example, we have identified a common anti-pattern we call 'batch-itis' in which a script fails and then cannot perform more work, even if that work is not precluded by the failure. The solution we have identified--removing unnecessary looping over independent units of work--is often easier to code than the anti-pattern, as it eliminates the need for complex control flow logic in the component. Other anti-patterns we have identified are similarly easy to identify and often easy to fix. We have drawn upon experience working with three science teams at Woods Hole Oceanographic Institution, each of which has designed novel imaging instruments and associated image analysis code. By developing use cases and prototypes within these teams, we have undertaken formal evaluations of software components developed by programmers with widely varying levels of expertise, and have been able to discover and characterize a number of anti-patterns. Our evaluation methodology and testbed have also enabled us to assess the efficacy of strategies to address these anti-patterns according to scientifically relevant metrics, such as ability of algorithms to perform faster than the rate of data acquisition and the accuracy of workflow component output relative to ground truth. The set of anti-patterns and solutions we have identified augments of the body of more well-known software engineering anti-patterns by addressing additional concerns that obtain when a software component has to function as part of a workflow assembled out of independently-developed codebases. Our experience shows that identifying and resolving these anti-patterns reduces development time and improves performance without reducing component reusability.

  11. Personality, work characteristics, and employee well-being: a longitudinal analysis of additive and moderating effects.

    PubMed

    Houkes, Inge; Janssen, Peter P M; de Jonge, Jan; Bakker, Arnold B

    2003-01-01

    This study tested the longitudinal influence of personality (measured by the characteristics growth need strength, negative affectivity [NA], and upward striving) on 3 psychological outcomes (intrinsic work motivation, emotional exhaustion, and turnover intention), using a pattern of specific relationships between work characteristics and these outcomes as a framework. The study hypotheses were tested in a multioccupational sample consisting of bank employees and teachers, using a 2-wave panel design with a 1-year time interval and structural equation modeling. NA had a cross-lagged direct and additive relationship with emotional exhaustion and also moderated the relationship between Time 1 workload and Time 2 emotional exhaustion. The authors concluded that NA may have multiple effects on emotional exhaustion that persist over time.

  12. A Time Use Diary Study of Adult Everyday Writing Behavior

    ERIC Educational Resources Information Center

    Cohen, Dale J.; White, Sheida; Cohen, Steffaney B.

    2011-01-01

    The present study documents everyday adult writing by type of text and medium (computer or paper) in an "in vivo" diary study. The authors compare writing patterns by gender, race/ethnicity, educational attainment, age and working status. The study results reveal that (a) writing time varied with demographic variables for networkers, but…

  13. Timed activity studies for assessing the energy expenditure of women from an urban slum in south India.

    PubMed

    Sujatha, Tetali; Shatrugna, Veena; Vidyasagar, P; Begum, Nazeema; Padmavathy, K S; Reddy, G Chenna Krishna; Rao, G V

    2003-06-01

    Time-disposition studies are necessary for computing energy requirements of populations. This study captures the rich information on the timed activity pattern of adult women from poor households engaged in home-based work. We studied 34 women beedimakers (cigarette makers), 21 tailors, and 34 homemakers. Data were collected by direct observation of the women's activities on a typical day. Time spent on related activities was pooled and classified as sleep, household work, child care, occupational work, and residual work. These were further categorized on the basis of our published work on the energy cost of women's activities and the World Health Organization (WHO) classification of occupational activities as sedentary, moderate, and heavy. Most of the household activities could be classified as moderate to heavy (> 2.2 times basal metabolic rate [BMR]). Childcare activities were distributed on a scale from sedentary to heavy, whereas occupational activities, such as beedimaking and tailoring, were sedentary (< 2.2 BMR). Homemakers spent significantly more time on moderate to heavy work (p < .05) than beedimakers and tailors. Women working for income spent only four to six hours on occupational work, which was possible because they reduced the time spent on heavy work (i.e., housework), and reduced the time on personal care. Still, more than 80% of women could not put in eight hours of paid work. Thus, women in the home-based sector constantly negotiate among time spent on heavy household work, child care, and occupational work in order to continue in the labor market.

  14. The Longitudinal Association between Multiple Substance Use Discrepancies and Marital Satisfaction

    PubMed Central

    Homish, Gregory G.; Leonard, Kenneth E.; Kozlowski, Lynn T.; Cornelius, Jack R.

    2009-01-01

    AIMS The objective of this work was to examine the relation between patterns of substance use among newly married couples and marital satisfaction over time. In particular, this work examined if differences between husbands’ and wives’ heavy alcohol use and cigarette smoking, rather than simply use per se, predicted decreases in marital satisfaction over the first seven years of marriage. METHODS Married couples (n=634 couples) were assessed on a variety of substance use and relationship variables at the time of marriage and again at the first, second, fourth and seventh year of marriage. RESULTS After controlling for key sociodemographic variables, discrepancies in husband and wife cigarette smoking and heavy alcohol use were related to significant reductions in marital satisfaction. Importantly, couples who were discrepant on both substances experienced the greatest declines in marital satisfaction over time. CONCLUSIONS Patterns of substance use among newly married couples are important predictors of changes in marital functioning over time. It was not simply the heavy alcohol use or cigarette smoking that predicted dissatisfaction, but rather, differences between husbands’ and wives’ substance use that impacted the relationship. PMID:19563563

  15. The longitudinal association between multiple substance use discrepancies and marital satisfaction.

    PubMed

    Homish, Gregory G; Leonard, Kenneth E; Kozlowski, Lynn T; Cornelius, Jack R

    2009-07-01

    The objective of this work was to examine the relation between patterns of substance use among newly married couples and marital satisfaction over time. In particular, this work examined if differences between husbands' and wives' heavy alcohol use and cigarette smoking, rather than simply use per se, predicted decreases in marital satisfaction over the first 7 years of marriage. Married couples (n = 634 couples) were assessed on a variety of substance use and relationship variables at the time of marriage and again at the first, second, fourth and seventh years of marriage. After controlling for key socio-demographic variables, discrepancies in husband and wife cigarette smoking and heavy alcohol use were related to significant reductions in marital satisfaction. Importantly, couples who were discrepant on both substances experienced the greatest declines in marital satisfaction over time. Patterns of substance use among newly married couples are important predictors of changes in marital functioning over time. It was not simply the heavy alcohol use or cigarette smoking that predicted dissatisfaction but, rather, differences between husbands' and wives' substance use that impacted the relationship.

  16. Organization of Anti-Phase Synchronization Pattern in Neural Networks: What are the Key Factors?

    PubMed Central

    Li, Dong; Zhou, Changsong

    2011-01-01

    Anti-phase oscillation has been widely observed in cortical neural network. Elucidating the mechanism underlying the organization of anti-phase pattern is of significance for better understanding more complicated pattern formations in brain networks. In dynamical systems theory, the organization of anti-phase oscillation pattern has usually been considered to relate to time delay in coupling. This is consistent to conduction delays in real neural networks in the brain due to finite propagation velocity of action potentials. However, other structural factors in cortical neural network, such as modular organization (connection density) and the coupling types (excitatory or inhibitory), could also play an important role. In this work, we investigate the anti-phase oscillation pattern organized on a two-module network of either neuronal cell model or neural mass model, and analyze the impact of the conduction delay times, the connection densities, and coupling types. Our results show that delay times and coupling types can play key roles in this organization. The connection densities may have an influence on the stability if an anti-phase pattern exists due to the other factors. Furthermore, we show that anti-phase synchronization of slow oscillations can be achieved with small delay times if there is interaction between slow and fast oscillations. These results are significant for further understanding more realistic spatiotemporal dynamics of cortico-cortical communications. PMID:22232576

  17. Changes in Training Opportunities in South Wales, 1945-1998: The Views of Key Informants. Patterns of Participation in Adult Education and Training. Working Paper 12.

    ERIC Educational Resources Information Center

    Chambers, Paul; Gorard, Stephen; Fevre, Ralph; Rees, Gareth; Furlong, John

    This study is part of a regional study in industrial South Wales on the determinants of participation and non-participation in post-compulsory education and training, with special reference to processes of change in the patterns of these determinants over time and to variations between geographical areas. The study combines analysis of secondary…

  18. A Local Agreement Pattern Measure Based on Hazard Functions for Survival Outcomes

    PubMed Central

    Dai, Tian; Guo, Ying; Peng, Limin; Manatunga, Amita K.

    2017-01-01

    Summary Assessing agreement is often of interest in biomedical and clinical research when measurements are obtained on the same subjects by different raters or methods. Most classical agreement methods have been focused on global summary statistics, which cannot be used to describe various local agreement patterns. The objective of this work is to study the local agreement pattern between two continuous measurements subject to censoring. In this paper, we propose a new agreement measure based on bivariate hazard functions to characterize the local agreement pattern between two correlated survival outcomes. The proposed measure naturally accommodates censored observations, fully captures the dependence structure between bivariate survival times and provides detailed information on how the strength of agreement evolves over time. We develop a nonparametric estimation method for the proposed local agreement pattern measure and study theoretical properties including strong consistency and asymptotical normality. We then evaluate the performance of the estimator through simulation studies and illustrate the method using a prostate cancer data example. PMID:28724196

  19. A local agreement pattern measure based on hazard functions for survival outcomes.

    PubMed

    Dai, Tian; Guo, Ying; Peng, Limin; Manatunga, Amita K

    2018-03-01

    Assessing agreement is often of interest in biomedical and clinical research when measurements are obtained on the same subjects by different raters or methods. Most classical agreement methods have been focused on global summary statistics, which cannot be used to describe various local agreement patterns. The objective of this work is to study the local agreement pattern between two continuous measurements subject to censoring. In this article, we propose a new agreement measure based on bivariate hazard functions to characterize the local agreement pattern between two correlated survival outcomes. The proposed measure naturally accommodates censored observations, fully captures the dependence structure between bivariate survival times and provides detailed information on how the strength of agreement evolves over time. We develop a nonparametric estimation method for the proposed local agreement pattern measure and study theoretical properties including strong consistency and asymptotical normality. We then evaluate the performance of the estimator through simulation studies and illustrate the method using a prostate cancer data example. © 2017, The International Biometric Society.

  20. Triboelectrification-Enabled Self-Powered Data Storage.

    PubMed

    Kuang, Shuang Yang; Zhu, Guang; Wang, Zhong Lin

    2018-02-01

    Data storage by any means usually requires an electric driving power for writing or reading. A novel approach for self-powered, triboelectrification-enabled data storage (TEDS) is presented. Data are incorporated into a set of metal-based surface patterns. As a probe slides across the patterned surface, triboelectrification between the scanning probe and the patterns produces alternatively varying voltage signal in quasi-square wave. The trough and crest of the quasi-square wave signal are coded as binary bits of "0" and "1," respectively, while the time span of the trough and the crest is associated with the number of bits. The storage of letters and sentences is demonstrated through either square-shaped or disc-shaped surface patterns. Based on experimental data and numerical calculation, the theoretically predicted maximum data storage density could reach as high as 38.2 Gbit in -2 . Demonstration of real-time data retrieval is realized with the assistance of software interface. For the TEDS reported in this work, the measured voltage signal is self-generated as a result of triboelectrification without the reliance on an external power source. This feature brings about not only low power consumption but also a much more simplified structure. Therefore, this work paves a new path to a unique approach of high-density data storage that may have widespread applications.

  1. Short-term and mid-term effects of fasting and downset meal pattern on lipid profile in Iranian fasted women.

    PubMed

    Rabiee, Samira; Afghari, Narsis; Rastmanesh, Reza

    2014-06-01

    It is not clear that whether the effects of fasting and downset meal pattern on lipid profile are limited only to Ramadan or do they remain after that month. The cohort study was conducted on 49 women aged 20-45 who worked at Shahid Motahari hospital in Isfahan. They put on groups of 23 consuming downset meal and 26 non-consuming downset meal persons. Serum triglyceride, cholesterol, LDL, and HDL were measured on the 3 days before the beginning, 3 and 30 days after the end of Ramadan. Repeated measure test was used to determine the changes during times and the interaction effects between times and nocturnal eating pattern. This study showed that fasting causes some short-term and mid-term changes in triglyceride and HDL that is mostly attributable to changes in dietary habits during Ramadan, rather than downset meal pattern.

  2. Normative data on the diurnal pattern of the Karolinska Sleepiness Scale ratings and its relation to age, sex, work, stress, sleep quality and sickness absence/illness in a large sample of daytime workers.

    PubMed

    Åkerstedt, Torbjorn; Hallvig, David; Kecklund, Göran

    2017-10-01

    Self-rated sleepiness responds to sleep loss, time of day and work schedules. There is, however, a lack of a normative reference showing the diurnal pattern during a normal working day, compared with a day off, as well as differences depending on stress, sleep quality, sex, age and being sick listed. The present study sought to provide such data for the Karolinska Sleepiness Scale. Participants were 431 individuals working in medium-sized public service units. Sleepiness (Karolinska Sleepiness Scale, scale 1-9) was rated at six times a day for a working week and 2 days off (>90.000 ratings). The results show a clear circadian pattern, with high values during the morning (4.5 at 07:00 hours) and evening (6.0 at 22:00 hours), and with low values (3-4) during the 10:00-16:00 hours span. Women had significantly higher (0.5 units) Karolinska Sleepiness Scale values than men, as did younger individuals (0.3 units), those with stress (1.3 units above the low-stress group) and those with poor sleep quality (1.0 units above those with qood sleep quality). Days off showed reduced sleepiness (0.7 units), while being sick listed was associated with an increased sleepiness (0.8 units). Multiple regression analysis of mean sleepiness during the working week yielded mean daytime stress, mean sleep quality, age, and sex as predictors (not sleep duration). Improved sleep quality accounted for the reduced sleepiness during days off, but reduced stress was a second factor. Similar results were obtained in a longitudinal mixed-model regression analysis across the 7 days of the week. The percentage of ratings at Karolinska Sleepiness Scale risk levels (8 + 9) was 6.6%, but most of these were obtained at 22:00 hours. It was concluded that sleepiness ratings are strongly associated with time of day, sleep quality, stress, work day/day off, being ill, age, and sex. © 2017 European Sleep Research Society.

  3. Constructing and predicting solitary pattern solutions for nonlinear time-fractional dispersive partial differential equations

    NASA Astrophysics Data System (ADS)

    Arqub, Omar Abu; El-Ajou, Ahmad; Momani, Shaher

    2015-07-01

    Building fractional mathematical models for specific phenomena and developing numerical or analytical solutions for these fractional mathematical models are crucial issues in mathematics, physics, and engineering. In this work, a new analytical technique for constructing and predicting solitary pattern solutions of time-fractional dispersive partial differential equations is proposed based on the generalized Taylor series formula and residual error function. The new approach provides solutions in the form of a rapidly convergent series with easily computable components using symbolic computation software. For method evaluation and validation, the proposed technique was applied to three different models and compared with some of the well-known methods. The resultant simulations clearly demonstrate the superiority and potentiality of the proposed technique in terms of the quality performance and accuracy of substructure preservation in the construct, as well as the prediction of solitary pattern solutions for time-fractional dispersive partial differential equations.

  4. Managing the double burden: pregnancy and labor-intensive time use in rural China, Mexico, and Tanzania.

    PubMed

    Peterman, Amber; Ng, Shu Wen; Palermo, Tia; Lee, I-Heng Emma

    2013-12-01

    Labor-intensive work is often a way of life for women living in rural areas of developing countries. The physical exertion involved in such work may result in poor health outcomes for mothers and infants when continued through pregnancy. Using longitudinal data from China, Mexico, and Tanzania, we examine the relationship between pregnancy and four time-use outcomes, measured as hours spent in the past week on: (1) housework, (2) caregiving, (3) agricultural work, and (4) self-employment or nonagricultural work outside the home. An individual fixed-effects approach is adopted to overcome the potential time-invariant woman-level endogeneity of pregnancy status. With few exceptions, we do not find significantly different time-use patterns between pregnant and nonpregnant women. The assumption that women decrease labor-intensive work in developing countries during pregnancy needs revisiting and may have implications for both women's livelihood programming and assistance during childbearing periods. © 2013 The Population Council, Inc.

  5. Working after a metastatic cancer diagnosis: Factors affecting employment in the metastatic setting from ECOG-ACRIN's Symptom Outcomes and Practice Patterns study.

    PubMed

    Tevaarwerk, Amye J; Lee, Ju-Whei; Terhaar, Abigail; Sesto, Mary E; Smith, Mary Lou; Cleeland, Charles S; Fisch, Michael J

    2016-02-01

    Improved survival for individuals with metastatic cancer accentuates the importance of employment for cancer survivors. A better understanding of how metastatic cancer affects employment is a necessary step toward the development of tools for assisting survivors in this important realm. The ECOG-ACRIN Symptom Outcomes and Practice Patterns study was analyzed to investigate what factors were associated with the employment of 680 metastatic cancer patients. Univariate and multivariate logistic regression analyses were conducted to compare patients stably working with patients no longer working. There were 668 metastatic working-age participants in the analysis: 236 (35%) worked full- or part-time, whereas 302 (45%) had stopped working because of illness. Overall, 58% reported some change in employment due to illness. A better performance status and non-Hispanic white ethnicity/race were significantly associated with continuing to work despite a metastatic cancer diagnosis in the multivariate analysis. The disease type, time since metastatic diagnosis, number of metastatic sites, location of metastatic disease, and treatment status had no significant impact. Among the potentially modifiable factors, receiving hormonal treatment (if a viable option) and decreasing symptom interference were associated with continuing to work. A significant percentage of the metastatic patients remained employed; increased symptom burden was associated with a change to no longer working. Modifiable factors resulting in work interference should be minimized so that patients with metastatic disease may continue working if this is desired. Improvements in symptom control and strategies developed to help address workplace difficulties have promise for improving this aspect of survivorship. © 2015 American Cancer Society.

  6. Cosmic strings and the microwave sky. I - Anisotropy from moving strings

    NASA Technical Reports Server (NTRS)

    Stebbins, Albert

    1988-01-01

    A method is developed for calculating the component of the microwave anisotropy around cosmic string loops due to their rapidly changing gravitational fields. The method is only valid for impact parameters from the string much smaller than the horizon size at the time the photon passes the string. The method makes it possible to calculate the temperature pattern around arbitrary string configurations numerically in terms of one-dimensional integrals. This method is applied to temperature jump across a string, confirming and extending previous work. It is also applied to cusps and kinks on strings, and to determining the temperature pattern far from a strong loop. The temperature pattern around a few loop configurations is explicitly calculated. Comparisons with the work of Brandenberger et al. (1986) indicates that they have overestimated the MBR anisotropy from gravitational radiation emitted from loops.

  7. Delivering the lateral inhibition punchline: it's all about the timing.

    PubMed

    Axelrod, Jeffrey D

    2010-10-26

    Experimental and theoretical biologists have long been fascinated with the emergence of self-organizing patterns in developing organisms, and much attention has focused on Notch-mediated lateral inhibition. Within sheets of cells that may adopt either of two possible cell fates, lateral inhibition establishes patterns through the activity of a negative intercellular feedback loop involving the receptor, Notch, and its ligands Delta or Serrate. Despite a long history of intensive study in Drosophila, where the mechanism was first described, as well as in other organisms, new work continues to yield important insights. Mathematical modeling, combined with biological analyses, has now shed light on two features of the process: how antagonistic and activating ligand-receptor interactions work together to accelerate inhibition and ensure fidelity, and how filopodial dynamics contribute to the observed pattern refinement and spacing.

  8. Qualitative research in psychology: Could William James get a job?

    PubMed

    Marchel, Carol; Owens, Stephanie

    2007-11-01

    Considering the case of William James, the author examines the likelihood of a successful career as a qualitative researcher in contemporary U.S. psychology. Fifty-seven journals affiliated with the American Psychological Association or its divisions were analyzed to show the place of qualitative research in U.S. psychology over the past 50 years. Journal abstracts, mission statements, and a short e-mail questionnaire from editors were used to understand patterns and trends in qualitative research in U.S. psychology. Editors are generally accepting of qualitative work, although mission statements do not always signal likely interest in qualitative work. The amount of qualitative work published is comparably low, but patterns of increased publication are found in some journals. Trends in methodologies, topics of research, and ways in which qualitative research enters journals over time are discussed. Suggestions for the publication of qualitative work are provided.

  9. Variation in Part-Time Work among Pediatric Subspecialties.

    PubMed

    Freed, Gary L; Boyer, Debra M; Van, Kenton D; Macy, Michelle L; McCormick, Julie; Leslie, Laurel K

    2018-04-01

    To assess the part-time workforce and average hours worked per week among pediatric subspecialists in the 15 medical subspecialties certified by the American Board of Pediatrics. We examined data from pediatric subspecialists who enrolled in Maintenance of Certification with the American Board of Pediatrics from 2009 to 2015. Data were collected via an online survey. Providers indicated whether they worked full time or part time and estimated the average number of hours worked per week in clinical, research, education, and administrative tasks, excluding time on call. We calculated and compared the range of hours worked by those in full- and part-time positions overall, by demographic characteristics, and by subspecialty. Overall, 9.6% of subspecialists worked part time. There was significant variation in part-time employment rates between subspecialties, ranging from 3.8% among critical care pediatricians to 22.9% among developmental-behavioral pediatricians. Women, American medical graduates, and physicians older than 70 years of age reported higher rates of part-time employment than men, international medical graduates, and younger physicians. There was marked variation in the number of hours worked across subspecialties. Most, but not all, full-time subspecialists reported working at least 40 hours per week. More than one-half of physicians working part time in hematology and oncology, pulmonology, and transplant hepatology reported working at least 40 hours per week. There are unique patterns of part-time employment and hours worked per week among pediatric medical subspecialists that make simple head counts inadequate to determine the effective workforce. Our findings are limited to the 15 American Board of Pediatrics-certified medical subspecialties. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Mothers' work patterns and Children's cognitive achievement: Evidence from the India Human Development survey.

    PubMed

    Vikram, Kriti; Chen, Feinian; Desai, Sonalde

    2018-05-01

    As female labor force participation increases globally, the relationship between maternal employment and children's development remains unclear. Using data from the India Human Development Survey (2005), we investigate the link between maternal employment and children's arithmetic and reading achievement. We develop a work pattern typology that goes beyond standard measures of employment and captures work intensity and its compatibility with child-rearing in a transitional economy. We find that the relationship between maternal employment and children's outcomes is not unidimensional. For example, children of self-employed mothers are not disadvantaged compared to those with stay-at-home mothers, but maternal employment in salaried jobs or wage work outside the home is negatively associated with cognitive skills in children. However, this negative association is reversed at higher levels of maternal education, suggesting greater access to resources and flexibility associated with better jobs mitigate the negative aspects of maternal employment posed by time constraints. Additionally, maternal employment is associated with maternal involvement in schoolwork and financial investment in academic activities, providing evidence that both time and resources devoted to children's education are significant. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Independent operation of implicit working memory under cognitive load.

    PubMed

    Ji, Eunhee; Lee, Kyung Min; Kim, Min-Shik

    2017-10-01

    Implicit working memory (WM) has been known to operate non-consciously and unintentionally. The current study investigated whether implicit WM is a discrete mechanism from explicit WM in terms of cognitive resource. To induce cognitive resource competition, we used a conjunction search task (Experiment 1) and imposed spatial WM load (Experiment 2a and 2b). Each trial was composed of a set of five consecutive search displays. The location of the first four displays appeared as per pre-determined patterns, but the fifth display could follow the same pattern or not. If implicit WM can extract the moving pattern of stimuli, response times for the fifth target would be faster when it followed the pattern compared to when it did not. Our results showed implicit WM can operate when participants are searching for the conjunction target and even while maintaining spatial WM information. These results suggest that implicit WM is independent from explicit spatial WM. Copyright © 2017. Published by Elsevier Inc.

  12. Experiments towards establishing of design rules for R2R-UV-NIL with polymer working shims

    NASA Astrophysics Data System (ADS)

    Nees, Dieter; Ruttloff, Stephan; Palfinger, Ursula; Stadlober, Barbara

    2016-03-01

    Roll-to-Roll-UV-nanoimprint lithography (R2R-UV-NIL) enables high resolution large area patterning of flexible substrates and is therefore of increasing industrial interest. We have set up a custom-made R2R-UV-NIL pilot machine which is able to convert 10 inch wide web with velocities of up to 30 m/min. In addition, we have developed self-replicable UV-curable resins with tunable surface energy and Young's modulus for UV-imprint material as well as for polymer working stamp/shim manufacturing. Now we have designed test patterns for the evaluation of the impact of structure shape, critical dimension, pitch, depth, side wall angle and orientation relative to the web movement onto the imprint fidelity and working shim life time. We have used female (recessed structures) silicon masters of that design with critical dimensions between CD = 200 nm and 1600 nm, and structure depths of d = 500 nm and 1000 nm - all with vertical as well as inclined side walls. These entire master patterns have been transferred onto single male (protruding structures) R2R polymer working shims. The polymer working shims have been used for R2R-UV-NIL runs of several hundred meters and the imprint fidelity and process stability of the various test patterns have been compared. This study is intended as a first step towards establishing of design rules and developing of nanoimprint proximity correction strategies for industrial R2R-UV-NIL processes using polymer working shims.

  13. Global patterns of phytoplankton dynamics in coastal ecosystems

    USGS Publications Warehouse

    Paerl, H.; Yin, Kedong; Cloern, J.

    2011-01-01

    Scientific Committee on Ocean Research Working Group 137 Meeting; Hangzhou, China, 17-21 October 2010; Phytoplankton biomass and community structure have undergone dramatic changes in coastal ecosystems over the past several decades in response to climate variability and human disturbance. These changes have short- and long-term impacts on global carbon and nutrient cycling, food web structure and productivity, and coastal ecosystem services. There is a need to identify the underlying processes and measure the rates at which they alter coastal ecosystems on a global scale. Hence, the Scientific Committee on Ocean Research (SCOR) formed Working Group 137 (WG 137), "Global Patterns of Phytoplankton Dynamics in Coastal Ecosystems: A Comparative Analysis of Time Series Observations" (http://wg137.net/). This group evolved from a 2007 AGU-sponsored Chapman Conference entitled "Long Time-Series Observations in Coastal Ecosystems: Comparative Analyses of Phytoplankton Dynamics on Regional to Global Scales.".

  14. Fast traffic sign recognition with a rotation invariant binary pattern based feature.

    PubMed

    Yin, Shouyi; Ouyang, Peng; Liu, Leibo; Guo, Yike; Wei, Shaojun

    2015-01-19

    Robust and fast traffic sign recognition is very important but difficult for safe driving assistance systems. This study addresses fast and robust traffic sign recognition to enhance driving safety. The proposed method includes three stages. First, a typical Hough transformation is adopted to implement coarse-grained location of the candidate regions of traffic signs. Second, a RIBP (Rotation Invariant Binary Pattern) based feature in the affine and Gaussian space is proposed to reduce the time of traffic sign detection and achieve robust traffic sign detection in terms of scale, rotation, and illumination. Third, the techniques of ANN (Artificial Neutral Network) based feature dimension reduction and classification are designed to reduce the traffic sign recognition time. Compared with the current work, the experimental results in the public datasets show that this work achieves robustness in traffic sign recognition with comparable recognition accuracy and faster processing speed, including training speed and recognition speed.

  15. Fast Traffic Sign Recognition with a Rotation Invariant Binary Pattern Based Feature

    PubMed Central

    Yin, Shouyi; Ouyang, Peng; Liu, Leibo; Guo, Yike; Wei, Shaojun

    2015-01-01

    Robust and fast traffic sign recognition is very important but difficult for safe driving assistance systems. This study addresses fast and robust traffic sign recognition to enhance driving safety. The proposed method includes three stages. First, a typical Hough transformation is adopted to implement coarse-grained location of the candidate regions of traffic signs. Second, a RIBP (Rotation Invariant Binary Pattern) based feature in the affine and Gaussian space is proposed to reduce the time of traffic sign detection and achieve robust traffic sign detection in terms of scale, rotation, and illumination. Third, the techniques of ANN (Artificial Neutral Network) based feature dimension reduction and classification are designed to reduce the traffic sign recognition time. Compared with the current work, the experimental results in the public datasets show that this work achieves robustness in traffic sign recognition with comparable recognition accuracy and faster processing speed, including training speed and recognition speed. PMID:25608217

  16. High performance embedded system for real-time pattern matching

    NASA Astrophysics Data System (ADS)

    Sotiropoulou, C.-L.; Luciano, P.; Gkaitatzis, S.; Citraro, S.; Giannetti, P.; Dell'Orso, M.

    2017-02-01

    In this paper we present an innovative and high performance embedded system for real-time pattern matching. This system is based on the evolution of hardware and algorithms developed for the field of High Energy Physics and more specifically for the execution of extremely fast pattern matching for tracking of particles produced by proton-proton collisions in hadron collider experiments. A miniaturized version of this complex system is being developed for pattern matching in generic image processing applications. The system works as a contour identifier able to extract the salient features of an image. It is based on the principles of cognitive image processing, which means that it executes fast pattern matching and data reduction mimicking the operation of the human brain. The pattern matching can be executed by a custom designed Associative Memory chip. The reference patterns are chosen by a complex training algorithm implemented on an FPGA device. Post processing algorithms (e.g. pixel clustering) are also implemented on the FPGA. The pattern matching can be executed on a 2D or 3D space, on black and white or grayscale images, depending on the application and thus increasing exponentially the processing requirements of the system. We present the firmware implementation of the training and pattern matching algorithm, performance and results on a latest generation Xilinx Kintex Ultrascale FPGA device.

  17. Defining a "Zone of Impact": Transport Processes and Patterns for Small-Scale Land Runoff.

    NASA Astrophysics Data System (ADS)

    Largier, J. L.; Basdurak, B.

    2016-12-01

    Nearshore pollution is a well-recognized environmental problem, yet the pattern of this pollution is not well studied and it is little recognized in policy. Whether nutrients, pathogens or toxins, the highest concentrations of pollutants in the nearfield are controlled by transport and mixing, rather than decay of the constituent. Thus, this becomes a challenge to determine patterns of runoff (and tidal outflow) and to account for the dominant processes that control these patterns. Salinity and fecal indicator bacteria data exhibit coherent space-time patterns, indicating that a coherent "zone of impact" can be determined, i.e., a time-varying spatial zone in which the constituent of concern exceeds a reference concentration (level of concern). To explain field observations, modeling of small-scale runoff plumes and wave-driven transport can be used. In contrast to larger river plumes, wind forcing is a critical factor in plume behavior and the resultant pattern of pollution. This preliminary work suggests that coherent spatio-temporal patterns can explain the apparently not-so-well-behaved patterns of pollution that are reported when concentrations are under-sampled. And it throws out a challenge to nearshore oceanographers to better explain transport and mixing patterns for the benefit of reducing coastal pollution and its impacts.

  18. Quantify work load and muscle functional activation patterns in neck-shoulder muscles of female sewing machine operators using surface electromyogram.

    PubMed

    Zhang, Fei-Ruo; He, Li-Hua; Wu, Shan-Shan; Li, Jing-Yun; Ye, Kang-Pin; Wang, Sheng

    2011-11-01

    Work-related musculoskeletal disorders (WMSDs) have high prevalence in sewing machine operators employed in the garment industry. Long work duration, sustained low level work and precise hand work are the main risk factors of neck-shoulder disorders for sewing machine operators. Surface electromyogram (sEMG) offers a valuable tool to determine muscle activity (internal exposure) and quantify muscular load (external exposure). During sustained and/or repetitive muscle contractions, typical changes of muscle fatigue in sEMG, as an increase in amplitude or a decrease as a shift in spectrum towards lower frequencies, can be observed. In this paper, we measured and quantified the muscle load and muscular activity patterns of neck-shoulder muscles in female sewing machine operators during sustained sewing machine operating tasks using sEMG. A total of 18 healthy women sewing machine operators volunteered to participate in this study. Before their daily sewing machine operating task, we measured the maximal voluntary contractions (MVC) and 20%MVC of bilateral cervical erector spinae (CES) and upper trapezius (UT) respectively, then the sEMG signals of bilateral UT and CES were monitored and recorded continuously during 200 minutes of sustained sewing machine operating simultaneously which equals to 20 time windows with 10 minutes as one time window. After 200 minutes' work, we retest 20%MVC of four neck-shoulder muscles and recorded the sEMG signals. Linear analysis, including amplitude probability distribution frequency (APDF), amplitude analysis parameters such as roof mean square (RMS) and spectrum analysis parameter as median frequency (MF), were used to calculate and indicate muscle load and muscular activity of bilateral CES and UT. During 200 minutes of sewing machine operating, the median load for the left cervical erector spinae (LCES), right cervical erector spinae (RCES), left upper trapezius (LUT) and right upper trapezius (RUT) were 6.78%MVE, 6.94%MVE, 6.47%MVE and 5.68%MVE, respectively. Work load of right muscles are significantly higher than that of the left muscles (P < 0.05); sEMG signal analysis of isometric contractions indicated that the amplitude value before operating was significantly higher than that of after work (P < 0.01), and the spectrum value of bilateral CES and UT were significantly lower than those of after work (P < 0.01); according to the sEMG signal data of 20 time windows, with operating time pass by, the muscle activity patterns of bilateral CES and UT showed dynamic changes, the maximal amplitude of LCES, RCES, LUT occurred at the 20th time window, RUT at 16th time window, spectrum analysis showed that the lower value happened at 7th, 16th, 20th time windows. Female sewing machine operators were exposed to high sustained static load on bilateral neck-shoulder muscles; left neck and shoulder muscles were held in more static positions; the 7th, 16th, and 20th time windows were muscle fatigue period that ergonomics intervention can protocol at these periods.

  19. Automated sample plan selection for OPC modeling

    NASA Astrophysics Data System (ADS)

    Casati, Nathalie; Gabrani, Maria; Viswanathan, Ramya; Bayraktar, Zikri; Jaiswal, Om; DeMaris, David; Abdo, Amr Y.; Oberschmidt, James; Krause, Andreas

    2014-03-01

    It is desired to reduce the time required to produce metrology data for calibration of Optical Proximity Correction (OPC) models and also maintain or improve the quality of the data collected with regard to how well that data represents the types of patterns that occur in real circuit designs. Previous work based on clustering in geometry and/or image parameter space has shown some benefit over strictly manual or intuitive selection, but leads to arbitrary pattern exclusion or selection which may not be the best representation of the product. Forming the pattern selection as an optimization problem, which co-optimizes a number of objective functions reflecting modelers' insight and expertise, has shown to produce models with equivalent quality to the traditional plan of record (POR) set but in a less time.

  20. An autocatalytic network model for stock markets

    NASA Astrophysics Data System (ADS)

    Caetano, Marco Antonio Leonel; Yoneyama, Takashi

    2015-02-01

    The stock prices of companies with businesses that are closely related within a specific sector of economy might exhibit movement patterns and correlations in their dynamics. The idea in this work is to use the concept of autocatalytic network to model such correlations and patterns in the trends exhibited by the expected returns. The trends are expressed in terms of positive or negative returns within each fixed time interval. The time series derived from these trends is then used to represent the movement patterns by a probabilistic boolean network with transitions modeled as an autocatalytic network. The proposed method might be of value in short term forecasting and identification of dependencies. The method is illustrated with a case study based on four stocks of companies in the field of natural resource and technology.

  1. General practitioner non-principals benefit from flexible working.

    PubMed

    French, Fiona; Andrew, Jane; Awramenko, Morag; Coutts, Helen; Leighton-Beck, Linda; Mollison, Jill; Needham, Gillian; Scott, Anthony; Walker, Kim

    2005-01-01

    The purpose of this study is to explore non-principals' working patterns and attitudes to work. The article is based on data provided by a questionnaire survey. Findings - Gender division was apparent among the non-principals. Males were more likely to work full-time, because their spouses modified their working hours. It was impossible to identify all non-principals in Scotland or to compare responders and non-responders, due to the lack of official data. Hence, the results might not be representative. More flexible posts would enable GPs to more easily combine paid work with family commitments. It is anticipated that the new GP contract should deliver this. This was the first time a study of all non-principals in Scotland had been attempted. The findings provide a more comprehensive picture of GPs in Scotland and provide valuable information for policymakers.

  2. A week in the life of full-time office workers: work day and weekend light exposure in summer and winter.

    PubMed

    Crowley, Stephanie J; Molina, Thomas A; Burgess, Helen J

    2015-01-01

    Little is known about the light exposure in full-time office workers, who spend much of their workdays indoors. We examined the 24-h light exposure patterns of 14 full-time office workers during a week in summer, and assessed their dim light melatonin onset (DLMO, a marker of circadian timing) at the end of the working week. Six workers repeated the study in winter. Season had little impact on the workers' schedules, as the timing of sleep, commute, and work did not vary by more than 30 min in the summer and winter. In both seasons, workers received significantly more morning light on workdays than weekends, due to earlier wake times and the morning commute. Evening light in the two hours before bedtime was consistently dim. The timing of the DLMO did not vary between season, and by the end of the working week, the workers slept at a normal circadian phase. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  3. A survey of dental hygienists in the United Kingdom in 2011. Part 1--demographics and working patterns as dental hygienists.

    PubMed

    Eaton, K A; Harris, M; Ross, M K; Arevalo, C

    2012-11-01

    The aims of this survey were to establish the demographic profile of dental hygienists (DHs) and dental hygienist/therapists (DH/Ts) in the United Kingdom in 2011 and their patterns of practice as DHs. A 10% sample of all those registered with the General Dental Council as DHs or DH/Ts in April 2011 were sent a pre-piloted questionnaire, explanatory letter and stamped addressed envelope. The questionnaire contained a total of 100 questions, 24 of which related to demographics and working patterns. All 100 questions were solely on tasks/work performed by DH, none related to other types of work performed by DH/Ts. Three mailings were distributed between May and July 2011. The resulting data were entered into an Excel spreadsheet. Where appropriate, differences between the responses from DHs and DH/Ts were statistically tested with the chi-squared test. Five hundred and sixty-one DHs and DH/Ts were sent the questionnaire, by the third mailing 371 (66.1%) had responded and returned completed questionnaires. The respondents were 288 DHs, 79 DH/Ts and 4 who did not specify which category they were. The mean year of qualification of the DHs was 1990 and for the DH/Ts 2005. One hundred and twenty-four (33%) reported that they worked full-time, 235 (63%) part-time and the remainder that they were not working as DHs or DH/Ts or had retired. The average number of clinical hours worked per week was reported as 24.6 hours for DHs and 25 hours for DH/Ts, but there were regional variations. For DHs the mean percentage of patients treated under NHS contract was 15.5% and for DH/Ts it was 40.2%. Again there were regional variations and in Scotland these figures were 45.5% for DHs and 70% for DH/Ts. Two hundred and forty-eight (69%) of all respondents were either fully or partly self-employed and 221 (62.7%) worked in two or more locations. The results of this study provide a snapshot of the demographics and practice patterns of DHs and DH/Ts in the UK in the summer of 2011. They confirm the results of a survey that was conducted in England in early 2011 and of a survey that took place in Scotland in 2009.

  4. Resistant to the recession: low-income adults' maintenance of cooking and away-from-home eating behaviors during times of economic turbulence.

    PubMed

    Smith, Lindsey P; Ng, Shu Wen; Popkin, Barry M

    2014-05-01

    We examined the effects of state-level unemployment rates during the recession of 2008 on patterns of home food preparation and away-from-home (AFH) eating among low-income and minority populations. We analyzed pooled cross-sectional data on 118 635 adults aged 18 years or older who took part in the American Time Use Study. Multinomial logistic regression models stratified by gender were used to evaluate the associations between state-level unemployment, poverty, race/ethnicity, and time spent cooking, and log binomial regression was used to assess respondents' AFH consumption patterns. High state-level unemployment was associated with only trivial increases in respondents' cooking patterns and virtually no change in their AFH eating patterns. Low-income and racial/ethnic minority groups were not disproportionately affected by the recession. Even during a major economic downturn, US adults are resistant to food-related behavior change. More work is needed to understand whether this reluctance to change is attributable to time limits, lack of knowledge or skill related to food preparation, or lack of access to fresh produce and raw ingredients.

  5. Resistant to the Recession: Low-Income Adults’ Maintenance of Cooking and Away-From-Home Eating Behaviors During Times of Economic Turbulence

    PubMed Central

    Smith, Lindsey P.; Ng, Shu Wen

    2014-01-01

    Objectives. We examined the effects of state-level unemployment rates during the recession of 2008 on patterns of home food preparation and away-from-home (AFH) eating among low-income and minority populations. Methods. We analyzed pooled cross-sectional data on 118 635 adults aged 18 years or older who took part in the American Time Use Study. Multinomial logistic regression models stratified by gender were used to evaluate the associations between state-level unemployment, poverty, race/ethnicity, and time spent cooking, and log binomial regression was used to assess respondents’ AFH consumption patterns. Results. High state-level unemployment was associated with only trivial increases in respondents’ cooking patterns and virtually no change in their AFH eating patterns. Low-income and racial/ethnic minority groups were not disproportionately affected by the recession. Conclusions. Even during a major economic downturn, US adults are resistant to food-related behavior change. More work is needed to understand whether this reluctance to change is attributable to time limits, lack of knowledge or skill related to food preparation, or lack of access to fresh produce and raw ingredients. PMID:24625145

  6. Adverse trajectories of mental health problems predict subsequent burnout and work-family conflict - a longitudinal study of employed women with children followed over 18 years.

    PubMed

    Nilsen, Wendy; Skipstein, Anni; Demerouti, Evangelia

    2016-11-08

    The long-term consequence of experiencing mental health problems may lead to several adverse outcomes. The current study aims to validate previous identified trajectories of mental health problems from 1993 to 2006 in women by examining their implications on subsequent work and family-related outcomes in 2011. Employed women (n = 439) with children were drawn from the Tracking Opportunities and Problems-Study (TOPP), a community-based longitudinal study following Norwegian families across 18 years. Previous identified latent profiles of mental health trajectories (i.e., High; Moderate; Low-rising and Low levels of mental health problems over time) measured at six time points between 1993 and 2006 were examined as predictors of burnout (e.g., exhaustion and disengagement from work) and work-family conflict in 2011 in univariate and multivariate analyses of variance adjusted for potential confounders (age, job demands, and negative emotionality). We found that having consistently High and Moderate symptoms as well as Low-Rising symptoms from 1993 to 2006 predicted higher levels of exhaustion, disengagement from work and work-family conflict in 2011. Findings remained unchanged when adjusting for several potential confounders, but when adjusting for current mental health problems only levels of exhaustion were predicted by the mental health trajectories. The study expands upon previous studies on the field by using a longer time span and by focusing on employed women with children who experience different patterns of mental health trajectories. The long-term effect of these trajectories highlight and validate the importance of early identification and prevention in women experiencing adverse patterns of mental health problems with regards to subsequent work and family-related outcomes.

  7. Persistent Scatterer Interferometry analysis of ground deformation in the Po Plain (Piacenza-Reggio Emilia sector, Northern Italy): seismo-tectonic implications

    NASA Astrophysics Data System (ADS)

    Antonielli, Benedetta; Monserrat, Oriol; Bonini, Marco; Cenni, Nicola; Devanthéry, Núria; Righini, Gaia; Sani, Federico

    2016-08-01

    This work aims to explore the ongoing tectonic activity of structures in the outermost sector of the Northern Apennines, which represents the active leading edge of the thrust belt and is dominated by compressive deformation. We have applied the Persistent Scatterer Interferometry (PSI) technique to obtain new insights into the present-day deformation pattern of the frontal area of the Northern Apennine. PSI has proved to be effective in detecting surface deformation of wide regions involved in low tectonic movements. We used 34 Envisat images in descending geometry over the period of time between 2004 and 2010, performing about 300 interferometric pairs. The analysis of the velocity maps and of the PSI time-series has allowed to observe ground deformation over the sector of the Po Plain between Piacenza and Reggio Emilia. The time-series of permanent GPS stations located in the study area, validated the results of the PSI technique, showing a good correlation with the PS time-series. The PS analysis reveals the occurrence of a well-known subsidence area on the rear of the Ferrara arc, mostly connected to the exploitation of water resources. In some instances, the PS velocity pattern reveals ground uplift (with mean velocities ranging from 1 to 2.8 mm yr-1) above active thrust-related anticlines of the Emilia and Ferrara folds, and part of the Pede-Apennine margin. We hypothesize a correlation between the observed uplift deformation pattern and the growth of the thrust-related anticlines. As the uplift pattern corresponds to known geological features, it can be used to constrain the seismo-tectonic setting, and a working hypothesis may involve that the active Emilia and Ferrara thrust folds would be characterized by interseismic periods possibly dominated by aseismic creep.

  8. Disentangling the causal relationships between work-home interference and employee health.

    PubMed

    van Hooff, Madelon L M; Geurts, Sabine A E; Taris, Toon W; Kompier, Michiel A J; Dikkers, Josje S E; Houtman, Irene L D; van den Heuvel, Floor M M

    2005-02-01

    The present study was designed to investigate the causal relationships between (time- and strain-based) work-home interference and employee health. The effort-recovery theory provided the theoretical basis for this study. Two-phase longitudinal data (with a 1-year time lag) were gathered from 730 Dutch police officers to test the following hypotheses with structural equation modeling: (i) work-home interference predicts health deterioration, (ii) health complaints precede increased levels of such interference, and (iii) both processes operate. The relationship between stable and changed levels of work-home interference across time and their relationships with the course of health were tested with a group-by-time analysis of variance. Four subgroups were created that differed in starting point and the development of work-home interference across time. The normal causal model, in which strain-based (but not time-based) work-home interference was longitudinally related to increased health complaints 1 year later, fit the data well and significantly better than the reversed causal model. Although the reciprocal model also provided a good fit, it was less parsimonious than the normal causal model. In addition, both an increment in (strain-based) work-home interference across time and a long-lasting experience of high (strain-based) work-home interference were associated with a deterioration in health. It was concluded that (strain-based) work-home interference acts as a precursor of health impairment and that different patterns of (strain-based) work-home interference across time are related to different health courses. Particularly long-term experience of (strain-based) work-home interference seems responsible for an accumulation of health complaints.

  9. A Study of Synchronous versus Asynchronous Collaboration in an Online Business Writing Class

    ERIC Educational Resources Information Center

    Mabrito, Mark

    2006-01-01

    A case study examined the collaborative experiences of students in an online business writing classroom. The purpose was to examine the same groups of students working on collaborative writing assignments in both a synchronous (real-time) and an asynchronous (non-real-time) discussion forum. This study focused on examining the amount, pattern, and…

  10. Person-Fit Statistics for Joint Models for Accuracy and Speed

    ERIC Educational Resources Information Center

    Fox, Jean-Paul; Marianti, Sukaesi

    2017-01-01

    Response accuracy and response time data can be analyzed with a joint model to measure ability and speed of working, while accounting for relationships between item and person characteristics. In this study, person-fit statistics are proposed for joint models to detect aberrant response accuracy and/or response time patterns. The person-fit tests…

  11. Directed self-assembly of poly(styrene)-block-poly(acrylic acid) copolymers for sub-20nm pitch patterning

    NASA Astrophysics Data System (ADS)

    Cheng, Jing; Lawson, Richard A.; Yeh, Wei-Ming; Jarnagin, Nathan D.; Peters, Andrew; Tolbert, Laren M.; Henderson, Clifford L.

    2012-03-01

    Directed self-assembly (DSA) of block copolymers is a promising technology for extending the patterning capability of current lithographic exposure tools. For example, production of sub-40 nm pitch features using 193nm exposure technologies is conceivably possible using DSA methods without relying on time consuming, challenging, and expensive multiple patterning schemes. Significant recent work has focused on demonstration of the ability to produce large areas of regular grating structures with low numbers of defects using self-assembly of poly(styrene)-b-poly(methyl methacrylate) copolymers (PS-b-PMMA). While these recent results are promising and have shown the ability to print pitches approaching 20 nm using DSA, the ability to advance to even smaller pitches will be dependent upon the ability to develop new block copolymers with higher χ values and the associated alignment and block removal processes required to achieve successful DSA with these new materials. This paper reports on work focused on identifying higher χ block copolymers and their associated DSA processes for sub-20 nm pitch patterning. In this work, DSA using polystyrene-b-polyacid materials has been explored. Specifically, it is shown that poly(styrene)-b-poly(acrylic acid) copolymers (PS-b-PAA) is one promising material for achieving substantially smaller pitch patterns than those possible with PS-b-PMMA while still utilizing simple hydrocarbon polymers. In fact, it is anticipated that much of the learning that has been done with the PS-b-PMMA system, such as development of highly selective plasma etch block removal procedures, can be directly leveraged or transferred to the PS-b-PAA system. Acetone vapor annealing of PS-b-PAA (Mw=16,000 g/mol with 50:50 mole ratio of PS:PAA) and its self-assembly into a lamellar morphology is demonstrated to generate a pattern pitch size (L0) of 21 nm. The χ value for PS-b-PAA was estimated from fingerprint pattern pitch data to be approximately 0.18 which is roughly 4.5 times greater than the χ for PS-b-PMMA (χPS-b-PMMA ~ 0.04).

  12. Wnt signaling underlies evolution and development of the butterfly wing pattern symmetry systems.

    PubMed

    Martin, Arnaud; Reed, Robert D

    2014-11-15

    Most butterfly wing patterns are proposed to be derived from a set of conserved pattern elements known as symmetry systems. Symmetry systems are so-named because they are often associated with parallel color stripes mirrored around linear organizing centers that run between the anterior and posterior wing margins. Even though the symmetry systems are the most prominent and diverse wing pattern elements, their study has been confounded by a lack of knowledge regarding the molecular basis of their development, as well as the difficulty of drawing pattern homologies across species with highly derived wing patterns. Here we present the first molecular characterization of symmetry system development by showing that WntA expression is consistently associated with the major basal, discal, central, and external symmetry system patterns of nymphalid butterflies. Pharmacological manipulations of signaling gradients using heparin and dextran sulfate showed that pattern organizing centers correspond precisely with WntA, wingless, Wnt6, and Wnt10 expression patterns, thus suggesting a role for Wnt signaling in color pattern induction. Importantly, this model is supported by recent genetic and population genomic work identifying WntA as the causative locus underlying wing pattern variation within several butterfly species. By comparing the expression of WntA between nymphalid butterflies representing a range of prototypical symmetry systems, slightly deviated symmetry systems, and highly derived wing patterns, we were able to infer symmetry system homologies in several challenging cases. Our work illustrates how highly divergent morphologies can be derived from modifications to a common ground plan across both micro- and macro-evolutionary time scales. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Working after a metastatic cancer diagnosis: factors affecting employment in the metastatic setting from ECOG’s Symptom Outcomes and Practice Patterns (SOAPP) study

    PubMed Central

    Tevaarwerk, Amye; Lee, Ju-Whei; Terhaar, Abigail; Sesto, Mary; Smith, Mary Lou; Cleeland, Charles; Fisch, Michael

    2015-01-01

    Background Improved survival for individuals with metastatic cancer accentuates the importance of employment for cancer survivors. Better understanding of how metastatic cancer affects employment is a necessary step towards the development of tools to assist survivors in this important realm. Methods We analyzed the Eastern Cooperative Oncology Group’s “Symptom Outcomes and Practice Patterns (SOAPP)” study to investigate what factors were associated with employment of 680 metastatic cancer patients. Univariable and multivariable logistic regression analyses were conducted to compare patients stably working (Group A) to patients no longer working (Group B). Results There were 668 metastatic working-age participants in our analysis; 236 (35%) worked full or part-time while 302 (45%) stopped working due to illness. Overall, 58% reported some change in employment due to illness. Better performance status and non-Hispanic White ethnicity/race were significantly associated with continuing to work despite a metastatic cancer diagnosis on multivariable analysis. Disease type, time since metastatic diagnosis, number of metastatic sites, location of metastatic disease, and treatment status had no significant impact. Among the potentially modifiable factors, receiving hormonal treatment (if a viable option) and decreasing symptom interference were associated with continuing to work. Conclusions A significant percentage of metastatic patients remain employed; symptom burden was associated with change to no longer working. Modifiable factors resulting in work interference should be minimized so that patients with metastatic disease may continue working, if desired. Improvements in symptom control and strategies developed to help address work place difficulties have promise to improve this aspect of survivorship. PMID:26687819

  14. Using artificial intelligence to improve identification of nanofluid gas-liquid two-phase flow pattern in mini-channel

    NASA Astrophysics Data System (ADS)

    Xiao, Jian; Luo, Xiaoping; Feng, Zhenfei; Zhang, Jinxin

    2018-01-01

    This work combines fuzzy logic and a support vector machine (SVM) with a principal component analysis (PCA) to create an artificial-intelligence system that identifies nanofluid gas-liquid two-phase flow states in a vertical mini-channel. Flow-pattern recognition requires finding the operational details of the process and doing computer simulations and image processing can be used to automate the description of flow patterns in nanofluid gas-liquid two-phase flow. This work uses fuzzy logic and a SVM with PCA to improve the accuracy with which the flow pattern of a nanofluid gas-liquid two-phase flow is identified. To acquire images of nanofluid gas-liquid two-phase flow patterns of flow boiling, a high-speed digital camera was used to record four different types of flow-pattern images, namely annular flow, bubbly flow, churn flow, and slug flow. The textural features extracted by processing the images of nanofluid gas-liquid two-phase flow patterns are used as inputs to various identification schemes such as fuzzy logic, SVM, and SVM with PCA to identify the type of flow pattern. The results indicate that the SVM with reduced characteristics of PCA provides the best identification accuracy and requires less calculation time than the other two schemes. The data reported herein should be very useful for the design and operation of industrial applications.

  15. Application of pattern recognition techniques to crime analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bender, C.F.; Cox, L.A. Jr.; Chappell, G.A.

    1976-08-15

    The initial goal was to evaluate the capabilities of current pattern recognition techniques when applied to existing computerized crime data. Performance was to be evaluated both in terms of the system's capability to predict crimes and to optimize police manpower allocation. A relation was sought to predict the crime's susceptibility to solution, based on knowledge of the crime type, location, time, etc. The preliminary results of this work are discussed. They indicate that automatic crime analysis involving pattern recognition techniques is feasible, and that efforts to determine optimum variables and techniques are warranted. 47 figures (RWR)

  16. Efficient processing of multiple nested event pattern queries over multi-dimensional event streams based on a triaxial hierarchical model.

    PubMed

    Xiao, Fuyuan; Aritsugi, Masayoshi; Wang, Qing; Zhang, Rong

    2016-09-01

    For efficient and sophisticated analysis of complex event patterns that appear in streams of big data from health care information systems and support for decision-making, a triaxial hierarchical model is proposed in this paper. Our triaxial hierarchical model is developed by focusing on hierarchies among nested event pattern queries with an event concept hierarchy, thereby allowing us to identify the relationships among the expressions and sub-expressions of the queries extensively. We devise a cost-based heuristic by means of the triaxial hierarchical model to find an optimised query execution plan in terms of the costs of both the operators and the communications between them. According to the triaxial hierarchical model, we can also calculate how to reuse the results of the common sub-expressions in multiple queries. By integrating the optimised query execution plan with the reuse schemes, a multi-query optimisation strategy is developed to accomplish efficient processing of multiple nested event pattern queries. We present empirical studies in which the performance of multi-query optimisation strategy was examined under various stream input rates and workloads. Specifically, the workloads of pattern queries can be used for supporting monitoring patients' conditions. On the other hand, experiments with varying input rates of streams can correspond to changes of the numbers of patients that a system should manage, whereas burst input rates can correspond to changes of rushes of patients to be taken care of. The experimental results have shown that, in Workload 1, our proposal can improve about 4 and 2 times throughput comparing with the relative works, respectively; in Workload 2, our proposal can improve about 3 and 2 times throughput comparing with the relative works, respectively; in Workload 3, our proposal can improve about 6 times throughput comparing with the relative work. The experimental results demonstrated that our proposal was able to process complex queries efficiently which can support health information systems and further decision-making. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. The role of monitoring interpretive rates, concordance between cytotechnologist and pathologist interpretations before sign-out, and turnaround time in gynecologic cytology quality assurance: findings from the College of American Pathologists Gynecologic Cytopathology Quality Consensus Conference working group 1.

    PubMed

    Clary, Karen M; Davey, Diane D; Naryshkin, Sonya; Austin, R Marshall; Thomas, Nicole; Chmara, Beth Anne; Sugrue, Chiara; Tworek, Joseph

    2013-02-01

    The College of American Pathologists (CAP) conducted a national survey of gynecologic cytology quality assurance (QA) practices. Experts in gynecologic cytology were asked to join 5 working groups that studied the survey data on different aspects of QA. Evaluating the survey data and follow-up questions online, together with a review of pertinent literature, the working groups developed a series of preliminary statements on good laboratory practices in cytology QA. These were presented at a consensus conference and electronic voting occurred. To evaluate a set of QA monitors in gynecologic cytology. Working group 1 evaluated (1) monitoring interpretive rate categories for Papanicolaou tests (Pap tests), (2) concordance of cytotechnologist and pathologist interpretations before sign-out, and (3) turnaround time for Pap tests. The statements are based on a survey of gynecologic cytology QA practice patterns and of opinions from working group members and consensus conference attendees. The outcomes of this process demonstrate the current state of practice patterns in gynecologic cytology QA. Monitoring interpretive rates for all Bethesda System categories is potentially useful, and it is most useful to monitor interpretive rates for cytotechnologists individually and in comparison to the entire laboratory. Laboratories need to determine what level of discrepancy between cytotechnologist and pathologist interpretations of Pap tests is important to track. Laboratories should consider formalizing procedures and policies to adjudicate such discrepant interpretations. Turnaround time should be monitored in gynecologic cytology, but individual laboratories should determine how to measure and use turnaround time internally.

  18. Fertility and patterns of labor force participation among married women.

    PubMed

    Smith-Lovin, L; Tickamyer, A R

    1981-01-01

    Variations in women's response to childbearing and participation in the labor force are examined with the expectation that 2 distinct patterns will emerge clarifying the fertility-work effect. The hypothesis is offered that 1 group of women will drop out entirely at the onset of childbearing, returning to work after the children have grown, if at all. Another group will work almost continuously with almost no gap in labor force participation. Past research, concentrating on averaged direction of causal flow, have obscured this bimodal distribution. 3 problems hamper the study of fertility effects on career discontinuity: detailed work and birth histories covering extended periods of time are scarce, variables often obscure variability, and censored histories are frequent in which the timing of an event may or may not occur until after the survey and therefore cannot be observed. Data for the analysis are from the 1970 EEO survey (Explorations in Equaltiy of Opportunity), a national sample survey of women who were high school sophomores in 1955. Using only complete data from women who were still married to their 1st husbands yielded a sample size of 703. Of these, 39% were working in 1970 and 85% had 2 or more children. Employment status, recorded for each year, was a dichotomous variable distinguishing between no employment during the year and any employment. The fertility variable indicated if a child was or was not adopted or born during the year. The women were much more likely to work before their 1st birth than afterwards, at least during the early adult years covered by this survey. Women who began childbearing while still in high school were more likely to continue working after birth. College graduates were also somewhat more likely to continue working after their 1st birth. 70% of the women worked before their 1st birth, 30% after the onset of childbearing. Work discontinuity, measured by the number of gaps in employment indicate that over 50% of the childless women have continuous work histories compared to 3% of the women with 4 or more children. 30% of the women with large families have 2 or more gaps and this group is also more likely to never have worked. Controlling for censored or truncated histories, a bimodal distribution is observed in analyzing time lapse in return to work after the 1st birth for women who were working at the time of the 1st birth. 35% continue to work without a detectable break and over 40% do not return after 5 or more years. Examining different parities reveals that the more children a woman will have, the less likely she is to continue working without a gap after her 1st birth and the more likely she is to have stayed out for an extended period. The dual pattern is still evident among higher parity women. Women who were not working at the time of their 1st birth are unlikely to enter the work force within 5 years of that birth. The association with small families (parity 1) is unclear due to the small number of cases. Different parity progressions have different patterns of labor force participation. 52% of the childless women and 38% parity 1 have continuous work histories, a rarity for women with 2 or more children. The results support several theoretical explanations. Normative interpretation may depict women oriented to traditional roles as allowing fertility to influence other decisions, while women oriented to the work role are influenced by work opportunity. The human capital interpretation suggests that women would be less likely to leave jobs with a high penalty for discontinuation, however all women who dropped out would be likely to stay out as their household labor became relatively more valuable than wage labor. The concept of career lines takes into consideration compatibility and prestige. Women in jobs with expected growth in salary and prestige will tend to have continuous work histories if the jobs are compatible with childbearing and if substantial losses are associated with gaps in participation.

  19. Intra-session repeatability of lower limb muscles activation pattern during pedaling.

    PubMed

    Dorel, Sylvain; Couturier, Antoine; Hug, François

    2008-10-01

    Assessment of intra-session repeatability of muscle activation pattern is of considerable relevance for research settings, especially when used to determine changes over time. However, the repeatability of lower limb muscles activation pattern during pedaling is not fully established. Thus, we tested the intra-session repeatability of the activation pattern of 10 lower limb muscles during a sub-maximal cycling exercise. Eleven triathletes participated to this study. The experimental session consisted in a reference sub-maximal cycling exercise (i.e. 150 W) performed before and after a 53-min simulated training session (mean power output=200+/-12 W). Repeatability of EMG patterns was assessed in terms of muscle activity level (i.e. RMS of the mean pedaling cycle and burst) and muscle activation timing (i.e. onset and offset of the EMG burst) for the 10 following lower limb muscles: gluteus maximus (GMax), semimembranosus (SM), Biceps femoris (BF), vastus medialis (VM), rectus femoris (RF), vastus lateralis (VL), gastrocnemius medianus (GM) and lateralis (GL), soleus (SOL) and tibialis anterior (TA). No significant differences concerning the muscle activation level were found between test and retest for all the muscles investigated. Only VM, SOL and TA showed significant differences in muscle activation timing parameters. Whereas ICC and SEM values confirmed this weak repeatability, cross-correlation coefficients suggest a good repeatability of the activation timing parameters for all the studied muscles. Overall, the main finding of this work is the good repeatability of the EMG pattern during pedaling both in term of muscle activity level and muscle activation timing.

  20. Job Sharing Through Part Time Contracts. A Consideration in the Context of Declining School Enrolments in Ontario.

    ERIC Educational Resources Information Center

    Kumar, Krishna

    Two questionnaires were sent to all school boards and a sample of teachers in Ontario to assess how receptive boards and teachers are to job sharing as an alternative work pattern in schools affected by declining enrollment. The report gives the background of the concept of job sharing and an analysis of the benefits, work situations, and problems…

  1. YieldStar based reticle 3D measurements and its application

    NASA Astrophysics Data System (ADS)

    Vaenkatesan, Vidya; Finders, Jo; ten Berge, Peter; Plug, Reinder; Sijben, Anko; Schellekens, Twan; Dillen, Harm; Pocobiej, Wojciech; Jorge, Vasco G.; van Dijck, Jurgen

    2016-09-01

    YieldStar (YS) is an established ASML-built scatterometer that is capable of measuring wafer Critical Dimension (CD), Overlay and Focus. In a recent work, the application range of YS was extended to measure 3D CD patterns on a reticle (pattern CD, height, Side Wall Angle-SWA). The primary motivation for this study came from imaging studies that indicated a need for measuring and controlling reticle 3D topography. CD scanning electron microscope (CD-SEM), Atomic force microscope (AFM), 3D multiple detector SEM (3D-SEM) are the preferred tools for reticle metrology. While these tools serve the industry well, the current research to the impact of reticle 3D involves extensive costs, logistic challenges and increased reticle lead time. YS provides an attractive alternative as it can measure pattern CD, SWA and height in a single measurement and at high throughput. This work demonstrates the capability of YS as a reticle metrology tool.

  2. Two-dimensional single-cell patterning with one cell per well driven by surface acoustic waves

    PubMed Central

    Collins, David J.; Morahan, Belinda; Garcia-Bustos, Jose; Doerig, Christian; Plebanski, Magdalena; Neild, Adrian

    2015-01-01

    In single-cell analysis, cellular activity and parameters are assayed on an individual, rather than population-average basis. Essential to observing the activity of these cells over time is the ability to trap, pattern and retain them, for which previous single-cell-patterning work has principally made use of mechanical methods. While successful as a long-term cell-patterning strategy, these devices remain essentially single use. Here we introduce a new method for the patterning of multiple spatially separated single particles and cells using high-frequency acoustic fields with one cell per acoustic well. We characterize and demonstrate patterning for both a range of particle sizes and the capture and patterning of cells, including human lymphocytes and red blood cells infected by the malarial parasite Plasmodium falciparum. This ability is made possible by a hitherto unexplored regime where the acoustic wavelength is on the same order as the cell dimensions. PMID:26522429

  3. Parareal algorithms with local time-integrators for time fractional differential equations

    NASA Astrophysics Data System (ADS)

    Wu, Shu-Lin; Zhou, Tao

    2018-04-01

    It is challenge work to design parareal algorithms for time-fractional differential equations due to the historical effect of the fractional operator. A direct extension of the classical parareal method to such equations will lead to unbalance computational time in each process. In this work, we present an efficient parareal iteration scheme to overcome this issue, by adopting two recently developed local time-integrators for time fractional operators. In both approaches, one introduces auxiliary variables to localized the fractional operator. To this end, we propose a new strategy to perform the coarse grid correction so that the auxiliary variables and the solution variable are corrected separately in a mixed pattern. It is shown that the proposed parareal algorithm admits robust rate of convergence. Numerical examples are presented to support our conclusions.

  4. Work Hours and Self rated Health of Hospital Doctors in Norway and Germany. A comparative study on national samples

    PubMed Central

    2011-01-01

    Background The relationship between extended work hours and health is well documented among hospital doctors, but the effect of national differences in work hours on health is unexplored. The study examines the relationship between work hours and self rated health in two national samples of hospital doctors. Methods The study population consisted of representative samples of 1,260 German and 562 Norwegian hospital doctors aged 25-65 years (N = 1,822) who received postal questionnaires in 2006 (Germany) and 2008 (Norway). The questionnaires contained items on demography, work hours (number of hours per workday and on-call per month) and self rated subjective health on a five point scale - dichotomized into "good" (above average) and "average or below". Results Compared to Norway, a significantly higher proportion of German doctors exceeded a 9 hour work day (58.8% vs. 26.7%) and 60 hours on-call per month (63.4% vs. 18.3%). Every third (32.2%) hospital doctor in Germany worked more than this, while this pattern was rare in Norway (2.9%). In a logistic regression model, working in Norway (OR 4.17; 95% CI 3.02-5.73), age 25-44 years (OR 1.66; 95% CI 1.29-2.14) and not exceeding 9 hour work day and 60 hours on-call per month (OR 1.35; 95% CI 1.03-1.77) were all independent significant predictors of good self reported health. Conclusion A lower percentage of German hospital doctors reported self rated health as "good", which is partly explained by the differences in work time pattern. Initiatives to increase doctors' control over their work time are recommended. PMID:21338494

  5. A work-family conflict/subjective well-being process model: a test of competing theories of longitudinal effects.

    PubMed

    Matthews, Russell A; Wayne, Julie Holliday; Ford, Michael T

    2014-11-01

    In the present study, we examine competing predictions of stress reaction models and adaptation theories regarding the longitudinal relationship between work-family conflict and subjective well-being. Based on data from 432 participants over 3 time points with 2 lags of varying lengths (i.e., 1 month, 6 months), our findings suggest that in the short term, consistent with prior theory and research, work-family conflict is associated with poorer subjective well-being. Counter to traditional work-family predictions but consistent with adaptation theories, after accounting for concurrent levels of work-family conflict as well as past levels of subjective well-being, past exposure to work-family conflict was associated with higher levels of subjective well-being over time. Moreover, evidence was found for reverse causation in that greater subjective well-being at 1 point in time was associated with reduced work-family conflict at a subsequent point in time. Finally, the pattern of results did not vary as a function of using different temporal lags. We discuss the theoretical, research, and practical implications of our findings. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  6. Art and Science

    ScienceCinema

    Murray Gibson

    2017-12-09

    Argonne's Murray Gibson is a physicist whose life's work includes finding patterns among atoms. The love of distinguishing patterns also drives Gibson as a musician and Blues enthusiast.Both artists and scientists rely on the principles of mathematics and physics, whether consciously or intuitively, to achieve their goals.And, at the same time, both science and art rely on the creative questioner to ask, "Why do we do it this way?" and "Why not try something else and see what happens?"

  7. Managing the double burden: Effects of pregnancy on labor-intensive time use in rural China, Mexico and Tanzania

    PubMed Central

    Peterman, Amber; Ng, Shu Wen; Palermo, Tia; Lee, I-Heng Emma

    2014-01-01

    Labor-intensive work is often a way of life for women in rural areas of developing countries. However, physical exertion may result in poor health outcomes for mother and infant if continued through pregnancy. Using longitudinal data from China, Mexico and Tanzania, we examine the relationship between pregnancy and four time use outcomes, measured as hours spent in the last week on: 1) housework, 2) care giving, 3) agricultural work, and 4) self-employed or non-agricultural work outside the home. An individual fixed effects approach is adopted to overcome potential time invariant woman-level endogeneity of pregnancy status. With a few exceptions, we do not find significantly different time use patterns between pregnant and non-pregnant women. The assumption that women decrease labor intensive work in developing countries during pregnancy needs revisiting, and may have implications for both women’s livelihood programming and assistance during childbearing periods. PMID:24323660

  8. Travel patterns during pregnancy: comparison between Global Positioning System (GPS) tracking and questionnaire data

    PubMed Central

    2013-01-01

    Background Maternal exposures to traffic-related air pollution have been associated with adverse pregnancy outcomes. Exposures to traffic-related air pollutants are strongly influenced by time spent near traffic. However, little is known about women’s travel activities during pregnancy and whether questionnaire-based data can provide reliable information on travel patterns during pregnancy. Objectives Examine women’s in-vehicle travel behavior during pregnancy and examine the difference in travel data collected by questionnaire and global positioning system (GPS) and their potential for exposure error. Methods We measured work-related travel patterns in 56 pregnant women using a questionnaire and one-week GPS tracking three times during pregnancy (<20 weeks, 20–30 weeks, and >30 weeks of gestation). We compared self-reported activities with GPS-derived trip distance and duration, and examined potentially influential factors that may contribute to differences. We also described in-vehicle travel behavior by pregnancy periods and influences of demographic and personal factors on daily travel times. Finally, we estimated personal exposure to particle-bound polycyclic aromatic hydrocarbon (PB-PAH) and examined the magnitude of exposure misclassification using self-reported vs. GPS travel data. Results Subjects overestimated both trip duration and trip distance compared to the GPS data. We observed moderately high correlations between self-reported and GPS-recorded travel distance (home to work trips: r = 0.88; work to home trips: r = 0.80). Better agreement was observed between the GPS and the self-reported travel time for home to work trips (r = 0.77) than work to home trips (r = 0.64). The subjects on average spent 69 and 93 minutes traveling in vehicles daily based on the GPS and self-reported data, respectively. Longer daily travel time was observed among participants in early pregnancy, and during certain pregnancy periods in women with higher education attainment, higher income, and no children. When comparing self-reported vs. GPS data, we found that estimated personal exposure to PB-PAH did not differ remarkably at the population level, but the difference was large at an individual level. Conclusion Self-reported home-to-work data overestimated both trip duration and trip distance compared to GPS data. Significant differences in PAH exposure estimates were observed at individual level using self-reported vs. GPS data, which has important implications in air pollution epidemiological studies. PMID:24107241

  9. The impact of reduced working hours on surgical training in Australia and New Zealand.

    PubMed

    Gough, Ian R

    2011-01-01

    There is a worldwide trend for reduced working hours for doctors, particularly in the developed western countries. This has been led by the introduction of the European Working Time Directive (EWTD) that has had a significant impact on work patterns and training. Australia currently has a more flexible working environment but this is changing. In New Zealand there is a contract for resident doctors defining a maximum 72 h of rostered work per week. Copyright © 2010 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

  10. PARLO: PArallel Run-Time Layout Optimization for Scientific Data Explorations with Heterogeneous Access Pattern

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gong, Zhenhuan; Boyuka, David; Zou, X

    Download Citation Email Print Request Permissions Save to Project The size and scope of cutting-edge scientific simulations are growing much faster than the I/O and storage capabilities of their run-time environments. The growing gap is exacerbated by exploratory, data-intensive analytics, such as querying simulation data with multivariate, spatio-temporal constraints, which induces heterogeneous access patterns that stress the performance of the underlying storage system. Previous work addresses data layout and indexing techniques to improve query performance for a single access pattern, which is not sufficient for complex analytics jobs. We present PARLO a parallel run-time layout optimization framework, to achieve multi-levelmore » data layout optimization for scientific applications at run-time before data is written to storage. The layout schemes optimize for heterogeneous access patterns with user-specified priorities. PARLO is integrated with ADIOS, a high-performance parallel I/O middleware for large-scale HPC applications, to achieve user-transparent, light-weight layout optimization for scientific datasets. It offers simple XML-based configuration for users to achieve flexible layout optimization without the need to modify or recompile application codes. Experiments show that PARLO improves performance by 2 to 26 times for queries with heterogeneous access patterns compared to state-of-the-art scientific database management systems. Compared to traditional post-processing approaches, its underlying run-time layout optimization achieves a 56% savings in processing time and a reduction in storage overhead of up to 50%. PARLO also exhibits a low run-time resource requirement, while also limiting the performance impact on running applications to a reasonable level.« less

  11. Utilizing Electronic Medical Records to Discover Changing Trends of Medical Behaviors Over Time.

    PubMed

    Yin, Liangying; Huang, Zhengxing; Dong, Wei; He, Chunhua; Duan, Huilong

    2017-05-05

    Medical behaviors are playing significant roles in the delivery of high quality and cost-effective health services. Timely discovery of changing frequencies of medical behaviors is beneficial for the improvement of health services. The main objective of this work is to discover the changing trends of medical behaviors over time. This study proposes a two-steps approach to detect essential changing patterns of medical behaviors from Electronic Medical Records (EMRs). In detail, a probabilistic topic model, i.e., Latent Dirichlet allocation (LDA), is firstly applied to disclose yearly treatment patterns in regard to the risk stratification of patients from a large volume of EMRs. After that, the changing trends by comparing essential/critical medical behaviors in a specific time period are detected and analyzed, including changes of significant patient features with their values, and changes of critical treatment interventions with their occurring time stamps. We verify the effectiveness of the proposed approach on a clinical dataset containing 12,152 patient cases with a time range of 10 years. Totally, 135 patients features and 234 treatment interventions in three treatment patterns were selected to detect their changing trends. In particular, evolving trends of yearly occurring probabilities of the selected medical behaviors were categorized into six content changing patterns (i.e, 112 growing, 123 declining, 43 up-down, 16 down-up, 35 steady, and 40 jumping), using the proposed approach. Besides, changing trends of execution time of treatment interventions were classified into three occurring time changing patterns (i.e., 175 early-implemented, 50 steady-implemented and 9 delay-implemented). Experimental results show that our approach has an ability to utilize EMRs to discover essential evolving trends of medical behaviors, and thus provide significant potential to be further explored for health services redesign and improvement.

  12. Visual and spatial working memory are not that dissociated after all: a time-based resource-sharing account.

    PubMed

    Vergauwe, Evie; Barrouillet, Pierre; Camos, Valérie

    2009-07-01

    Examinations of interference between visual and spatial materials in working memory have suggested domain- and process-based fractionations of visuo-spatial working memory. The present study examined the role of central time-based resource sharing in visuo-spatial working memory and assessed its role in obtained interference patterns. Visual and spatial storage were combined with both visual and spatial on-line processing components in computer-paced working memory span tasks (Experiment 1) and in a selective interference paradigm (Experiment 2). The cognitive load of the processing components was manipulated to investigate its impact on concurrent maintenance for both within-domain and between-domain combinations of processing and storage components. In contrast to both domain- and process-based fractionations of visuo-spatial working memory, the results revealed that recall performance was determined by the cognitive load induced by the processing of items, rather than by the domain to which those items pertained. These findings are interpreted as evidence for a time-based resource-sharing mechanism in visuo-spatial working memory.

  13. Integration of active pauses and pattern of muscular activity during computer work.

    PubMed

    St-Onge, Nancy; Samani, Afshin; Madeleine, Pascal

    2017-09-01

    Submaximal isometric muscle contractions have been reported to increase variability of muscle activation during computer work; however, other types of active contractions may be more beneficial. Our objective was to determine which type of active pause vs. rest is more efficient in changing muscle activity pattern during a computer task. Asymptomatic regular computer users performed a standardised 20-min computer task four times, integrating a different type of pause: sub-maximal isometric contraction, dynamic contraction, postural exercise and rest. Surface electromyographic (SEMG) activity was recorded bilaterally from five neck/shoulder muscles. Root-mean-square decreased with isometric pauses in the cervical paraspinals, upper trapezius and middle trapezius, whereas it increased with rest. Variability in the pattern of muscular activity was not affected by any type of pause. Overall, no detrimental effects on the level of SEMG during active pauses were found suggesting that they could be implemented without a cost on activation level or variability. Practitioner Summary: We aimed to determine which type of active pause vs. rest is best in changing muscle activity pattern during a computer task. Asymptomatic computer users performed a standardised computer task integrating different types of pauses. Muscle activation decreased with isometric pauses in neck/shoulder muscles, suggesting their implementation during computer work.

  14. Gender Differences in Participatory Leadership: An Examination of Principals' Time Spent Working with Others

    ERIC Educational Resources Information Center

    Sebastian, James; Moon, Jeong-Mi

    2017-01-01

    The purpose of this study was to examine whether female principals have a more participatory style compared to their male counterparts by examining principals' daily time allocation patterns. The study analyzed data from End of Day (EOD) survey logs from principals in an urban school district in the United States. Results from hierarchical linear…

  15. Coherent Pattern Prediction in Swarms of Delay-Coupled Agents

    NASA Astrophysics Data System (ADS)

    Mier-Y-Teran-Romero, Luis; Forgoston, Eric; Scwartz, Ira

    2013-03-01

    We consider a general swarm model of self-propelling particles interacting through a pairwise potential in the presence of a fixed communication time delay. Previous work has shown that swarms with communication time delays and noise may display pattern transitions that depend on the size of the coupling amplitude. We extend these results by completely unfolding the bifurcation structure of the mean field approximation. Our analysis reveals a direct correspondence between the different dynamical behaviors found in different regions of the coupling-time delay plane with the different classes of simulated coherent swarm patterns. We derive the spatio-temporal scales of the swarm structures, and also demonstrate how the complicated interplay of coupling strength, time delay, noise intensity, and choice of initial conditions can affect the swarm. In addition, when adding noise to the system, we find that for sufficiently large values of the coupling strength and/or the time delay, there is a noise intensity threshold that forces a transition of the swarm from a misaligned state into an aligned state. We show that this alignment transition exhibits hysteresis when the noise intensity is taken to be time dependent. Office of Naval Research, NIH (LMR and IBS) and NRL (EF)

  16. Cerebrovascular pattern improved by ozone autohemotherapy: an entropy-based study on multiple sclerosis patients.

    PubMed

    Molinari, Filippo; Rimini, Daniele; Liboni, William; Acharya, U Rajendra; Franzini, Marianno; Pandolfi, Sergio; Ricevuti, Giovanni; Vaiano, Francesco; Valdenassi, Luigi; Simonetti, Vincenzo

    2017-08-01

    Ozone major autohemotherapy is effective in reducing the symptoms of multiple sclerosis (MS) patients, but its effects on brain are still not clear. In this work, we have monitored the changes in the cerebrovascular pattern of MS patients and normal subjects during major ozone autohemotherapy by using near-infrared spectroscopy (NIRS) as functional and vascular technique. NIRS signals are analyzed using a combination of time, time-frequency analysis and nonlinear analysis of intrinsic mode function signals obtained from empirical mode decomposition technique. Our results show that there is an improvement in the cerebrovascular pattern of all subjects indicated by increasing the entropy of the NIRS signals. Hence, we can conclude that the ozone therapy increases the brain metabolism and helps to recover from the lower activity levels which is predominant in MS patients.

  17. Dental family stress and coping patterns.

    PubMed

    Nevin, R S; Sampson, V M

    1986-10-01

    This exploratory study of 28 married male dentists and their families was designed to gain an understanding about the stressors that dentists and their spouses experience, the life events and family strains they incur, the behavioral coping patterns they utilize, and their psychosocial characteristics. The study found that although stable dental families did encounter a significant number of stressors arising from both the dental practice and the family, they maintained their sense of balance through strong family coping skills and family resources. The effect of the dentist's office-related stress was directly felt in the family, especially by the spouse. Strong coping patterns resulted when dentists and spouses maintained a balance of time and responsibility, satisfaction in work and family activity, regular communication, sharing of decision making, good physical health, and the inclusion of an active exercise program within multiple demands on their time.

  18. Class and eating: Family meals in Britain.

    PubMed

    Jarosz, Ewa

    2017-09-01

    This paper examines social differentiation in eating patterns in Britain. It focuses on family meals among individuals with under-age children. Eating with family members has been associated with improvement in wellbeing, nutritional status, and school performance of the children. Modern lifestyles may pose a challenge to commensal eating for all groups, but the scale of the impact varies between social classes, with some groups at higher risk of shortening or skipping family meal time. Eating patterns are differentiated by individual's social class; they have also been associated with educational attainment, work schedules, and household composition. The objective of this study is to disaggregate the effect of these variables. Using data from the 2014/2015 UK Time Use Survey I analyse the net effect of social class, education, income, work and family characteristics on the frequency and duration of family meals. Individuals in the highest occupational class dedicate more time overall to family meals. However, class effect becomes insignificant when other variables, such as education or income, are controlled for. This study finds that higher educated individuals have more frequent family meals, and more affluent individuals spend more time at the table with their household members. Work characteristics are associated with frequency of meals, but not with their duration. Finally, household composition matters for how people eat. Parents of younger children eat with their family members more frequently than parents of teenagers. Single parents, a notoriously time-poor category, spend the least amount of time eating with their families and have fewer commensal meals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. What happens between pure hydraulic and buckling mechanisms of blowout fractures?

    PubMed

    Nagasao, Tomohisa; Miyamoto, Junpei; Shimizu, Yusuke; Jiang, Hua; Nakajima, Tatsuo

    2010-06-01

    The present study aims to evaluate how the ratio of the hydraulic and buckling mechanisms affects blowout fracture patterns, when these two mechanisms work simultaneously. Three-dimensional computer-aided-design (CAD)models were generated simulating ten skulls. To simulate impact, 1.2J was applied on the orbital region of these models in four patterns. Pattern 1: All the energy works to cause the hydraulic effect. Pattern 2: Two-thirds of the energy works to cause the hydraulic effect; one-third of the energy works to cause the buckling effect. Pattern 3: One-third of the energy works to cause the hydraulic effect; two-thirds of the energy works to cause the buckling effect. Pattern 4: The entire energy quantum works to cause the buckling effect. Using the finite element method, the regions where fractures were theoretically expected to occur were calculated and were compared between the four patterns. More fracture damage occurred for Pattern 1 than Pattern 2, and for Pattern 3 than for Pattern 4. The hydraulic and buckling mechanisms interact with one another. When these two mechanisms are combined, the orbital walls tend to develop serious fractures. Copyright (c) 2009 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  20. Spatial and temporal selectivity patterns of fires in Attika, Greece from 1984 to 2015 delineated from Landsat time series satellite images

    NASA Astrophysics Data System (ADS)

    Stamos, Zoi; Koutsias, Nikos

    2017-04-01

    The aim of this study is to assess spatial and temporalfire selectivity patterns in the region of Attica - Greece from 1984 to 2015. Our work is implemented in two distinct phases: the first consists of the accurate delineation of the fire perimeter using satellite remote sensing technology, and the second consists of the application of suitable GIS supported analyses to develop thematic layers that optimally summarised the spatial and temporal information of fire occurrence. Fire perimeters of wildland fires occurred within the time window 1984-2015 were delineated from freely available Landsat images from USGS and ESA sources.More than three thousands satellite images were processed in order to extract fire perimeters and create maps of fire frequency and fire return interval. In total one thousand and one hundred twenty fire perimeters were recorded during this thirty years' period. Fire perimeters within each year of fire occurrence were compared against the available to burn under complete random processes to identify selectivity patterns over (i) CORINE land use/land cover, (ii) fire frequency and (iii) time since last firemaps. For example, non- irrigated arable lands, complex cultivation patterns and discontinuous urban fabrics are negative related with fires, while coniferous forests, sclerophyllous vegetation and transitional woodlands seem to be preferable by the fires. Additionally, it seems that fires prefer their old burnings (two and three times burned) and also places with different patterns of time since last fire depending on the time needed by the type of vegetation to recover and thus to re-burn.

  1. Visualizing Dynamic Bitcoin Transaction Patterns.

    PubMed

    McGinn, Dan; Birch, David; Akroyd, David; Molina-Solana, Miguel; Guo, Yike; Knottenbelt, William J

    2016-06-01

    This work presents a systemic top-down visualization of Bitcoin transaction activity to explore dynamically generated patterns of algorithmic behavior. Bitcoin dominates the cryptocurrency markets and presents researchers with a rich source of real-time transactional data. The pseudonymous yet public nature of the data presents opportunities for the discovery of human and algorithmic behavioral patterns of interest to many parties such as financial regulators, protocol designers, and security analysts. However, retaining visual fidelity to the underlying data to retain a fuller understanding of activity within the network remains challenging, particularly in real time. We expose an effective force-directed graph visualization employed in our large-scale data observation facility to accelerate this data exploration and derive useful insight among domain experts and the general public alike. The high-fidelity visualizations demonstrated in this article allowed for collaborative discovery of unexpected high frequency transaction patterns, including automated laundering operations, and the evolution of multiple distinct algorithmic denial of service attacks on the Bitcoin network.

  2. Visualizing Dynamic Bitcoin Transaction Patterns

    PubMed Central

    McGinn, Dan; Birch, David; Akroyd, David; Molina-Solana, Miguel; Guo, Yike; Knottenbelt, William J.

    2016-01-01

    Abstract This work presents a systemic top-down visualization of Bitcoin transaction activity to explore dynamically generated patterns of algorithmic behavior. Bitcoin dominates the cryptocurrency markets and presents researchers with a rich source of real-time transactional data. The pseudonymous yet public nature of the data presents opportunities for the discovery of human and algorithmic behavioral patterns of interest to many parties such as financial regulators, protocol designers, and security analysts. However, retaining visual fidelity to the underlying data to retain a fuller understanding of activity within the network remains challenging, particularly in real time. We expose an effective force-directed graph visualization employed in our large-scale data observation facility to accelerate this data exploration and derive useful insight among domain experts and the general public alike. The high-fidelity visualizations demonstrated in this article allowed for collaborative discovery of unexpected high frequency transaction patterns, including automated laundering operations, and the evolution of multiple distinct algorithmic denial of service attacks on the Bitcoin network. PMID:27441715

  3. Alternative Work Patterns as Innovations in the Work Place. Overview: ERIC Fact Sheet No. 19.

    ERIC Educational Resources Information Center

    Denniston, Denie

    Alternative work patterns are work schedules that allow employees to select the hours and length of their workweeks. Reasons for choosing alternative work patterns include transportation considerations, participation in outside activities, ability to work better during certain hours, child care, and household commitments. Examples of alternative…

  4. Data Flow Analysis and Visualization for Spatiotemporal Statistical Data without Trajectory Information.

    PubMed

    Kim, Seokyeon; Jeong, Seongmin; Woo, Insoo; Jang, Yun; Maciejewski, Ross; Ebert, David S

    2018-03-01

    Geographic visualization research has focused on a variety of techniques to represent and explore spatiotemporal data. The goal of those techniques is to enable users to explore events and interactions over space and time in order to facilitate the discovery of patterns, anomalies and relationships within the data. However, it is difficult to extract and visualize data flow patterns over time for non-directional statistical data without trajectory information. In this work, we develop a novel flow analysis technique to extract, represent, and analyze flow maps of non-directional spatiotemporal data unaccompanied by trajectory information. We estimate a continuous distribution of these events over space and time, and extract flow fields for spatial and temporal changes utilizing a gravity model. Then, we visualize the spatiotemporal patterns in the data by employing flow visualization techniques. The user is presented with temporal trends of geo-referenced discrete events on a map. As such, overall spatiotemporal data flow patterns help users analyze geo-referenced temporal events, such as disease outbreaks, crime patterns, etc. To validate our model, we discard the trajectory information in an origin-destination dataset and apply our technique to the data and compare the derived trajectories and the original. Finally, we present spatiotemporal trend analysis for statistical datasets including twitter data, maritime search and rescue events, and syndromic surveillance.

  5. Accurate, fast, and secure biometric fingerprint recognition system utilizing sensor fusion of fingerprint patterns

    NASA Astrophysics Data System (ADS)

    El-Saba, Aed; Alsharif, Salim; Jagapathi, Rajendarreddy

    2011-04-01

    Fingerprint recognition is one of the first techniques used for automatically identifying people and today it is still one of the most popular and effective biometric techniques. With this increase in fingerprint biometric uses, issues related to accuracy, security and processing time are major challenges facing the fingerprint recognition systems. Previous work has shown that polarization enhancementencoding of fingerprint patterns increase the accuracy and security of fingerprint systems without burdening the processing time. This is mainly due to the fact that polarization enhancementencoding is inherently a hardware process and does not have detrimental time delay effect on the overall process. Unpolarized images, however, posses a high visual contrast and when fused (without digital enhancement) properly with polarized ones, is shown to increase the recognition accuracy and security of the biometric system without any significant processing time delay.

  6. Social class, gender, and time use: implications for the social determinants of body weight?

    PubMed

    McLaren, Lindsay; Godley, Jenny; MacNairn, Ian A S

    2009-12-01

    The social gradient in body weight (for example, obesity) departs from the social gradient in other health outcomes. Innovative approaches are needed to understand the observed patterns. This study examines time-use patterns by indicators of socio-economic position, and considers the implications of variations in time use for the social gradient in weight reported in other studies. The data are from respondents aged 25 to 64 to Canada's 1986 and 2005 General Social Surveys, which focused on time use. Participation in various activities was examined by sex, and by personal income and education, stratified by sex, in both years. Higher-income men and women were more likely than those of lower income to spend time in paid work, commuting and eating out, and less likely to spend time sleeping. Men and women with higher education were more likely than those with lower education to spend time in physical activity (2005 only) and reading. These time-use patterns plausibly contribute to the social gradient in obesity reported in other Canadian studies. The findings suggest that there is value in looking beyond a narrow range of health behaviours toward broader measures of daily routines to gain insight into the social determinants of weight and health.

  7. Intrinsic Work Value-Reward Dissonance and Work Satisfaction during Young Adulthood

    PubMed Central

    Porfeli, Erik J.; Mortimer, Jeylan T.

    2010-01-01

    Previous research suggests that discrepancies between work values and rewards are indicators of dissonance that induce change in both to reduce such dissonance over time. The present study elaborates this model to suggest parallels with the first phase of the extension- and-strain curve. Small discrepancies or small increases in extension are presumed to be almost unnoticeable, while increasingly large discrepancies are thought to yield exponentially increasing strain. Work satisfaction is a principal outcome of dissonance; hence, work value-reward discrepancies are predicted to diminish work satisfaction in an exponential fashion. Findings from the work and family literature, however, lead to the prediction that this curvilinear association will be moderated by gender and family roles. Using longitudinal data spanning the third decade of life, the results suggest that intrinsic work value-reward discrepancies, as predicted, are increasingly associated, in a negative curvilinear fashion, with work satisfaction. This pattern, however, differs as a function of gender and family roles. Females who established family roles exhibited the expected pattern while other gender by family status groups did not. The results suggest that gender and family roles moderate the association between intrinsic work value-reward dissonance and satisfaction. In addition, women who remained unmarried and childless exhibited the strongest associations between occupational rewards and satisfaction. PMID:20526434

  8. Intrinsic Work Value-Reward Dissonance and Work Satisfaction during Young Adulthood.

    PubMed

    Porfeli, Erik J; Mortimer, Jeylan T

    2010-06-01

    Previous research suggests that discrepancies between work values and rewards are indicators of dissonance that induce change in both to reduce such dissonance over time. The present study elaborates this model to suggest parallels with the first phase of the extension- and-strain curve. Small discrepancies or small increases in extension are presumed to be almost unnoticeable, while increasingly large discrepancies are thought to yield exponentially increasing strain. Work satisfaction is a principal outcome of dissonance; hence, work value-reward discrepancies are predicted to diminish work satisfaction in an exponential fashion. Findings from the work and family literature, however, lead to the prediction that this curvilinear association will be moderated by gender and family roles. Using longitudinal data spanning the third decade of life, the results suggest that intrinsic work value-reward discrepancies, as predicted, are increasingly associated, in a negative curvilinear fashion, with work satisfaction. This pattern, however, differs as a function of gender and family roles. Females who established family roles exhibited the expected pattern while other gender by family status groups did not. The results suggest that gender and family roles moderate the association between intrinsic work value-reward dissonance and satisfaction. In addition, women who remained unmarried and childless exhibited the strongest associations between occupational rewards and satisfaction.

  9. Relating interesting quantitative time series patterns with text events and text features

    NASA Astrophysics Data System (ADS)

    Wanner, Franz; Schreck, Tobias; Jentner, Wolfgang; Sharalieva, Lyubka; Keim, Daniel A.

    2013-12-01

    In many application areas, the key to successful data analysis is the integrated analysis of heterogeneous data. One example is the financial domain, where time-dependent and highly frequent quantitative data (e.g., trading volume and price information) and textual data (e.g., economic and political news reports) need to be considered jointly. Data analysis tools need to support an integrated analysis, which allows studying the relationships between textual news documents and quantitative properties of the stock market price series. In this paper, we describe a workflow and tool that allows a flexible formation of hypotheses about text features and their combinations, which reflect quantitative phenomena observed in stock data. To support such an analysis, we combine the analysis steps of frequent quantitative and text-oriented data using an existing a-priori method. First, based on heuristics we extract interesting intervals and patterns in large time series data. The visual analysis supports the analyst in exploring parameter combinations and their results. The identified time series patterns are then input for the second analysis step, in which all identified intervals of interest are analyzed for frequent patterns co-occurring with financial news. An a-priori method supports the discovery of such sequential temporal patterns. Then, various text features like the degree of sentence nesting, noun phrase complexity, the vocabulary richness, etc. are extracted from the news to obtain meta patterns. Meta patterns are defined by a specific combination of text features which significantly differ from the text features of the remaining news data. Our approach combines a portfolio of visualization and analysis techniques, including time-, cluster- and sequence visualization and analysis functionality. We provide two case studies, showing the effectiveness of our combined quantitative and textual analysis work flow. The workflow can also be generalized to other application domains such as data analysis of smart grids, cyber physical systems or the security of critical infrastructure, where the data consists of a combination of quantitative and textual time series data.

  10. Dynamic model based on voltage transfer curve for pattern formation in dielectric barrier glow discharge

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Ben; He, Feng; Ouyang, Jiting, E-mail: jtouyang@bit.edu.cn

    2015-12-15

    Simulation work is very important for understanding the formation of self-organized discharge patterns. Previous works have witnessed different models derived from other systems for simulation of discharge pattern, but most of these models are complicated and time-consuming. In this paper, we introduce a convenient phenomenological dynamic model based on the basic dynamic process of glow discharge and the voltage transfer curve (VTC) to study the dielectric barrier glow discharge (DBGD) pattern. VTC is an important characteristic of DBGD, which plots the change of wall voltage after a discharge as a function of the initial total gap voltage. In the modeling,more » the combined effect of the discharge conditions is included in VTC, and the activation-inhibition effect is expressed by a spatial interaction term. Besides, the model reduces the dimensionality of the system by just considering the integration effect of current flow. All these greatly facilitate the construction of this model. Numerical simulations turn out to be in good accordance with our previous fluid modeling and experimental result.« less

  11. Analysis of strawberry ripening by dynamic speckle measurements

    NASA Astrophysics Data System (ADS)

    Mulone, C.; Budini, N.; Vincitorio, F. M.; Freyre, C.; López Díaz, A. J.; Ramil Rego, A.

    2013-11-01

    This work seeks to determine the age of a fruit from observation of its dynamic speckle pattern. A mobile speckle pattern originates on the fruit's surface due to the interference of the wavefronts reflected from moving scatterers. For this work we analyzed two series of photographs of a strawberry speckle pattern, at different stages of ripening, acquired with a CMOS camera. The first day, we took ten photographs at an interval of one second. The same procedure was repeated the next day. From each series of images we extracted several statistical descriptors of pixel-to-pixel gray level variation during the observation time. By comparing these values from the first to the second day we noticed a diminution of the speckle activity. This decay demonstrated that after only one day the ripening process of the strawberry can be detected by dynamic speckle pattern analysis. For this study we employed a simple new algorithm to process the data obtained from the photographs. This algorithm allows defining a global mobility index that indicates the evolution of the fruit's ripening.

  12. Working under pressure: a pilot study of nurse work in a postoperative setting.

    PubMed

    Willis, Karen; Brown, Claire R; Sahlin, Ingrid; Svensson, Björn; Arnetz, Bengt B; Arnetz, Judith E

    2005-01-01

    Postoperative services provide an excellent setting to study nursing work due to the patients' needing highly technical, yet highly comforting, care. The current study examined nursing work in postoperative services in an attempt to discern how nursing work is structured. Observations of nursing interactions in a 14-bed postoperative unit of a large Swedish university hospital found that nursing work in this setting is highly intensive and multidimensional. The need to provide nursing interactions that are caring and respectful of patients, while at the same time ensuring a high level of technical capacity, was obvious throughout all stages of patient stays in this unit. Furthermore, although each interaction is necessarily time-limited there is a caring relationship sustained with each patient. There is a pattern of caring that emerges that can be encapsulated as a "contingent routine." Nursing work cannot be broken down into "dimensions of caring." The work is high-pressure and involves, by necessity, multitasking. There are many dimensions of nursing care, but, usually, these are supplied simultaneously.

  13. Lower back pain in nurses working in home care: linked to work-family conflict, emotional dissonance, and appreciation?

    PubMed

    Elfering, Achim; Häfliger, Evelyne; Celik, Zehra; Grebner, Simone

    2018-07-01

    In industrial countries home care services for elderly people living in the community are growing rapidly. Home care nursing is intensive and the nurses often suffer from musculoskeletal pain. Time pressure and job control are job-related factors linked to the risk of experiencing lower back pain (LBP) and LBP-related work impairment. This survey investigated whether work-family conflict (WFC), emotional dissonance and being appreciated at work have incremental predictive value. Responses were obtained from 125 home care nurses (63% response rate). Multiple linear regression showed that emotional dissonance and being appreciated at work predicted LBP intensity and LBP-related disability independently of time pressure and job control. WFC was not a predictor of LBP-related disability in multiple regression analyses despite a zero-order correlation with it. Redesigning the working pattern of home care nurses to reduce the emotional demands and improve appreciation of their work might reduce the incidence of LBP in this group.

  14. Determination of traffic intensity from camera images using image processing and pattern recognition techniques

    NASA Astrophysics Data System (ADS)

    Mehrübeoğlu, Mehrübe; McLauchlan, Lifford

    2006-02-01

    The goal of this project was to detect the intensity of traffic on a road at different times of the day during daytime. Although the work presented utilized images from a section of a highway, the results of this project are intended for making decisions on the type of intervention necessary on any given road at different times for traffic control, such as installation of traffic signals, duration of red, green and yellow lights at intersections, and assignment of traffic control officers near school zones or other relevant locations. In this project, directional patterns are used to detect and count the number of cars in traffic images over a fixed area of the road to determine local traffic intensity. Directional patterns are chosen because they are simple and common to almost all moving vehicles. Perspective vision effects specific to each camera orientation has to be considered, as they affect the size and direction of patterns to be recognized. In this work, a simple and fast algorithm has been developed based on horizontal directional pattern matching and perspective vision adjustment. The results of the algorithm under various conditions are presented and compared in this paper. Using the developed algorithm, the traffic intensity can accurately be determined on clear days with average sized cars. The accuracy is reduced on rainy days when the camera lens contains raindrops, when there are very long vehicles, such as trucks or tankers, in the view, and when there is very low light around dusk or dawn.

  15. The impact of unwaged domestic work on the duration and timing of sleep of female nurses working full-time on rotating 3-shift rosters.

    PubMed

    Clissold, G; Smith, P; Acutt, B

    2001-12-01

    The study examined the impact of family type on the timing and duration of sleep of 16 experienced female shiftworkers working a rotating 3-shift roster. The nurses lived in one of three domestic lifestyle arrangements: single with no child care responsibilities (N = 4), partnered with no child care responsibilities (N = 5) and partnered with child care responsibilities (N = 7). Self report sleep diaries were used to collect data over a period of 28 days, following which each nurse took part in a conversational interview. Comparisons of the roster mean sleep durations between groups show that nurses who do not have the added unwaged workload of child care, record significantly more sleep than nurses with such responsibilities. Analysis of the data by shift type shows a significant difference for afternoon shift: nurses with child care responsibilities record a significantly earlier rise time and a significantly shorter total sleep duration. The interview data further highlights how sleep patterns are related to the time constraints of both domestic and waged work.

  16. Time-frequency characterisation of paediatric heart sounds

    NASA Astrophysics Data System (ADS)

    Leung, Terence Sze-Tat

    1998-08-01

    The operation of the heart can be monitored by the sounds it emits. Structural defects or malfunction of the heart valves will cause additional abnormal sounds such as murmurs and ejection clicks. This thesis aims to characterise the heart sounds of three groups of children who either have an Atrial Septal Defect (ASD), a Ventricular Septal Defect (VSD), or are normal. Two aspects of heart sounds have been specifically investigated; the time-frequency analysis of systolic murmurs and the identification of splitting patterns in the second heart sound. The analysis is based on 42 paediatric heart sound recordings. Murmurs are sounds generated by turbulent flow of blood in the heart. They can be found in patients with both pathological and non-pathological conditions. The acoustic quality of the murmurs generated in each heart condition are different. The first aspect of this work is to characterise the three types of murmurs in the time- frequency domain. Modern time-frequency methods including, the Wigner-Ville Distribution, Smoothed Pseudo Wigner-Ville Distribution, Choi-Williams Distribution and spectrogram have been applied to characterise the murmurs. It was found that the three classes of murmurs exhibited different signatures in their time-frequency representations. By performing Discriminant Analysis, it was shown that spectral features extracted from the time- frequency representations can be used to distinguish between the three classes. The second aspect of the research is to identify splitting patterns in the second heart sound, which consists of two acoustic components due to the closure of the aortic valve and pulmonary valve. The aortic valve usually closes before the pulmonary valve, introducing a time delay known as 'split'. The split normally varies in duration over the respiratory cycle. In certain pathologies such as the ASD, the split becomes fixed over the respiration cycle. A technique based on adaptive signal decomposition is developed to measure the split and hence to identify the splitting pattern as either 'variable' or 'fixed'. This work has successfully characterised the murmurs and splitting patterns in the three groups of patients. Features extracted can be used for diagnostic purposes.

  17. Shift work parameters and disruption of diurnal cortisol production in female hospital employees.

    PubMed

    Hung, Eleanor Wai Man; Aronson, Kristan J; Leung, Michael; Day, Andrew; Tranmer, Joan

    2016-01-01

    Shift work is associated with an increased risk of cardiovascular diseases (CVD). Disruption of cortisol production is a potential underlying mechanism. This study explored the associations of diurnal quantity and pattern of cortisol production in relation to (1) current shift work status (exclusive day versus rotating days and nights), (2) years of past shift work and (3) parameters of rotating shift work (timing, length and intensity). Female hospital employees (160 day workers and 168 rotating shift workers) from southeastern Ontario, Canada, participated in a cross-sectional study. Participants completed a baseline questionnaire and measures of body height, weight, and waist circumference were taken. Midstream urine samples were collected over two separate 24-hour periods to measure creatinine-adjusted cortisol. Total diurnal cortisol production and pattern were described with two measures of the area under the curve. The effect of shift work on cortisol was modeled using multivariable linear regression analyses. Cortisol production in day workers and shift workers on their day shift were similar; however, shift workers on the night shift had flatter diurnal cortisol curves and produced less cortisol. This suggests that night work is associated with an acute attenuation of cortisol production.

  18. [Variables related to the emergence of differential patterns in work motivation].

    PubMed

    Arrieta, Carlos; Navarro, José; Vicente, Susana

    2008-11-01

    Several longitudinal studies have shown that motivation at work acts chaotically. In very few cases, it may be linear or random. However, the factors that might explain why these different patterns emerge have not been analysed to date. In this exploratory study, we interviewed 73 employees whose motivational patterns were previously known. The results revealed that chaotic patterns were associated with high levels of motivation, self-efficacy beliefs, and perceptions of instrumentality, and also with intrinsic personal goal orientation and a perception of high work control. Linear patterns were associated with extrinsic goals and a perception of work as difficult, and random patterns were linked to high flexibility at work.

  19. Rotating night shift work, sleep quality, selected lifestyle factors and prolactin concentration in nurses and midwives.

    PubMed

    Bukowska, Agnieszka; Sobala, Wojciech; Peplonska, Beata

    2015-04-01

    The pattern of secretion of many hormones, including prolactin, is dependent on the circadian rhythm. Night shift work involves exposure to artificial light at night and sleep deficiency, which in turn can affect prolactin synthesis. The aim of this study was to evaluate a possible association between night shift work characteristics, sleep quality, lifestyle factors and prolactin concentration, using data from a cross-sectional study of nurses and midwives. A cross-sectional study was conducted among 327 nurses and midwives currently working on rotating night shifts, and 330 nurses and midwives working during the day (aged 40-60 years) (388 premenopausal and 269 postmenopausal). Information about night shift work characteristics, lifestyle, reproductive factors, sleep pattern and other covariates was collected through a face-to-face interview, and from a one-week work and sleep diary completed by the subjects. Weight and height were measured. Prolactin concentration was measured in the morning blood sample using the electrochemiluminesence immunoassay method. Associations were analyzed using linear regression models adjusted for important confounders. Analyses were carried out separately in pre- and postmenopausal women. None of the night shift work or sleep characteristics was significantly associated with prolactin concentration. Prolactin concentration was significantly (p < 0.05) inversely associated with smoking and time of blood sample collection. These results were consistent among both pre- and postmenopausal women. Nulliparity was significantly positively associated with prolactin among premenopausal women, but inversely among postmenopausal. Age was related to prolactin among postmenopausal women only. Our study indicates that rotating night shift work is not associated with prolactin concentration. Smoking, parity, time of blood collection and age among postmenopausal women were significant determinants of prolactin.

  20. A real-time assessment of work stress in physicians and nurses.

    PubMed

    Rutledge, Thomas; Stucky, Erin; Dollarhide, Adrian; Shively, Martha; Jain, Sonia; Wolfson, Tanya; Weinger, Matthew B; Dresselhaus, Timothy

    2009-03-01

    This study adapted ecological momentary assessment methods to: (a) examine differences in work stress between nurses and physicians, and (b) to study relationships between work stress, work activity patterns, and sleep. A total of 185 physicians and 119 nurses (206 women, 98 men) working in four teaching hospitals participated in an observational study of work stress. Participants carried handheld computers that randomly prompted them for work activity, patient load, and work stress information. Participants completed more than 9,500 random interval surveys during the study (an average of 30.8 surveys per person-week). Approximately 85% of all surveys were completed in full (73.3%) or partially (11.6%). Emotional stress scores among physicians were nearly 50% higher (26.9[19.0]) than those of nurses (18.1[14.9], r[302] = .37, p < .001). Direct and indirect care activities were associated with higher stress reports by both clinician groups (rs[159] = .14-.26, ps < .01). Sleep quality and quantity were predictors of work stress scores (ps < .05). Finally, higher work stress and lower sleep quality were also associated with poorer memory performance (r[302] = -.12, .17, ps < 05). The findings identify patterns of work stress in relationship to work activities, sleep habits, and provider differences that may be used to assist ongoing hospital work reform efforts. (c) 2009 APA, all rights reserved

  1. The effect of cerebral palsy on arithmetic accuracy is mediated by working memory, intelligence, early numeracy, and instruction time.

    PubMed

    Jenks, Kathleen M; de Moor, Jan; van Lieshout, Ernest C D M; Maathuis, Karel G B; Keus, Inge; Gorter, Jan Willem

    2007-01-01

    The development of addition and subtraction accuracy was assessed in first graders with cerebral palsy (CP) in both mainstream (16) and special education (41) and a control group of first graders in mainstream education (16). The control group out-performed the CP groups in addition and subtraction accuracy and this difference could not be fully explained by differences in intelligence. Both CP groups showed evidence of working memory deficits. The three groups exhibited different developmental patterns in the area of early numeracy skills. Children with CP in special education were found to receive less arithmetic instruction and instruction time was positively related to arithmetic accuracy. Structural equation modeling revealed that the effect of CP on arithmetic accuracy is mediated by intelligence, working memory, early numeracy, and instruction time.

  2. Impossible meals? The food and meal situation of flight attendants in Scandinavia - A qualitative interview study.

    PubMed

    Nyberg, Maria; Lennernäs Wiklund, Maria

    2017-06-01

    The working conditions of flight attendants (FAs) often involve extended and irregular working hours, short rest periods, difficulties in planning for breaks and high demands of service provision. Moreover, work schedules including early check-in, shifts during circadian low and time-zone transitions imply constant exposure to alterations in circadian systems and related health risks. The aim of this explorative study was to investigate how the organisation of work, time and place influence the food and meal situation of FAs when at work, focusing on patterns, form and social context of meals. The research questions posed were how food and meals at work were characterised and perceived among the FAs, and what strategies were adopted to manage the food and meal situation. Qualitative, semi-structured interviews were conducted with fourteen FAs working in Scandinavia. The results indicated that the organisation of work, time and place have a major influence on the meal situation at work, and how food and meals are perceived and managed by FAs. The work was defined as fragmented and inconsistent regarding time and place resulting in scattered meals and a more snack-based form of eating. The meal situation was characterised by irregularity as well as unpredictability. Eating took place when food was available and when there was enough time to eat, rather than being guided by hunger or social context. Various strategies such as eating in prevention, using emergency food, avoiding certain food and drinks or eating little or nothing at all were used to manage the unpredictability of the meal situation as well as the gap between organisational and individual times. The findings demonstrated the individual responsibility to solve the meal at work, e.g. to solve organisational times. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. A Gaussian mixture model based adaptive classifier for fNIRS brain-computer interfaces and its testing via simulation

    NASA Astrophysics Data System (ADS)

    Li, Zheng; Jiang, Yi-han; Duan, Lian; Zhu, Chao-zhe

    2017-08-01

    Objective. Functional near infra-red spectroscopy (fNIRS) is a promising brain imaging technology for brain-computer interfaces (BCI). Future clinical uses of fNIRS will likely require operation over long time spans, during which neural activation patterns may change. However, current decoders for fNIRS signals are not designed to handle changing activation patterns. The objective of this study is to test via simulations a new adaptive decoder for fNIRS signals, the Gaussian mixture model adaptive classifier (GMMAC). Approach. GMMAC can simultaneously classify and track activation pattern changes without the need for ground-truth labels. This adaptive classifier uses computationally efficient variational Bayesian inference to label new data points and update mixture model parameters, using the previous model parameters as priors. We test GMMAC in simulations in which neural activation patterns change over time and compare to static decoders and unsupervised adaptive linear discriminant analysis classifiers. Main results. Our simulation experiments show GMMAC can accurately decode under time-varying activation patterns: shifts of activation region, expansions of activation region, and combined contractions and shifts of activation region. Furthermore, the experiments show the proposed method can track the changing shape of the activation region. Compared to prior work, GMMAC performed significantly better than the other unsupervised adaptive classifiers on a difficult activation pattern change simulation: 99% versus  <54% in two-choice classification accuracy. Significance. We believe GMMAC will be useful for clinical fNIRS-based brain-computer interfaces, including neurofeedback training systems, where operation over long time spans is required.

  4. JPRS Report, Soviet Union, Political Affairs

    DTIC Science & Technology

    1988-10-26

    Christa Wolfs novel "Patterns of Childhood." This very sensitive and timely work reflects the psychology attending the rise of fascism. We also have...incriminating evidence and extenuating circumstances? Psychologically , it is extremely difficult. There are allegations, there are sus- picions, there are...Zionism, which has for a long time been chipping away at the socialist foundation of our society, with its perfidious psychological methods." What does

  5. If an Adolescent Begins To Fail in School, What Can Parents and Teachers Do? ERIC Digest.

    ERIC Educational Resources Information Center

    Robertson, Anne S.

    Many teens experience a time when keeping up with school work is difficult. Some adolescents are able to get through this time with minimal assistance from their parents or teachers. However, when the difficulties last longer than a single grading period or are linked to a long-term pattern of poor school performance, parents and teachers may need…

  6. Real-time range acquisition by adaptive structured light.

    PubMed

    Koninckx, Thomas P; Van Gool, Luc

    2006-03-01

    The goal of this paper is to provide a "self-adaptive" system for real-time range acquisition. Reconstructions are based on a single frame structured light illumination. Instead of using generic, static coding that is supposed to work under all circumstances, system adaptation is proposed. This occurs on-the-fly and renders the system more robust against instant scene variability and creates suitable patterns at startup. A continuous trade-off between speed and quality is made. A weighted combination of different coding cues--based upon pattern color, geometry, and tracking--yields a robust way to solve the correspondence problem. The individual coding cues are automatically adapted within a considered family of patterns. The weights to combine them are based on the average consistency with the result within a small time-window. The integration itself is done by reformulating the problem as a graph cut. Also, the camera-projector configuration is taken into account for generating the projection patterns. The correctness of the range maps is not guaranteed, but an estimation of the uncertainty is provided for each part of the reconstruction. Our prototype is implemented using unmodified consumer hardware only and, therefore, is cheap. Frame rates vary between 10 and 25 fps, dependent on scene complexity.

  7. Pattern Recognition for a Flight Dynamics Monte Carlo Simulation

    NASA Technical Reports Server (NTRS)

    Restrepo, Carolina; Hurtado, John E.

    2011-01-01

    The design, analysis, and verification and validation of a spacecraft relies heavily on Monte Carlo simulations. Modern computational techniques are able to generate large amounts of Monte Carlo data but flight dynamics engineers lack the time and resources to analyze it all. The growing amounts of data combined with the diminished available time of engineers motivates the need to automate the analysis process. Pattern recognition algorithms are an innovative way of analyzing flight dynamics data efficiently. They can search large data sets for specific patterns and highlight critical variables so analysts can focus their analysis efforts. This work combines a few tractable pattern recognition algorithms with basic flight dynamics concepts to build a practical analysis tool for Monte Carlo simulations. Current results show that this tool can quickly and automatically identify individual design parameters, and most importantly, specific combinations of parameters that should be avoided in order to prevent specific system failures. The current version uses a kernel density estimation algorithm and a sequential feature selection algorithm combined with a k-nearest neighbor classifier to find and rank important design parameters. This provides an increased level of confidence in the analysis and saves a significant amount of time.

  8. A gender-based analysis of work patterns, fatigue, and work/life balance among physicians in postgraduate training.

    PubMed

    Gander, Philippa; Briar, Celia; Garden, Alexander; Purnell, Heather; Woodward, Alistair

    2010-09-01

    To document fatigue in New Zealand junior doctors in hospital-based clinical training positions and identify work patterns associated with work/life balance difficulties. This workforce has had a duty limitation of 72 hours/week since 1985. The authors chose a gender-based analytical approach because of the increasing proportion of female medical graduates. The authors mailed a confidential questionnaire to all 2,154 eligible junior doctors in 2003. The 1,412 respondents were working > or = 40 hours/week (complete questionnaires from 1,366: response rate: 63%; 49% women). For each participant, the authors calculated a multidimensional fatigue risk score based on sleep and work patterns. Women were more likely to report never/rarely getting enough sleep (P < .05), never/rarely waking refreshed (P < .001), and excessive sleepiness (P < .05) and were less likely to live with children up to 12 years old (P < .001). Fatigue risk scores differed by specialty but not by gender.Fatigue risk scores in the highest tertile were an independent risk factor for reporting problems in social life (odds ratio: 3.83; 95% CI: 2.79-5.28), home life (3.37; 2.43-4.67), personal relationships (2.12; 1.57-2.86), and other commitments (3.06; 2.23-4.19).Qualitative analyses indicated a common desire among men and women for better work/life balance and for part-time work, particularly in relation to parenthood. Limitation of duty hours alone is insufficient to manage fatigue risk and difficulties in maintaining work/life balance. These findings have implications for schedule design, professional training, and workforce planning.

  9. Time-Varying Networks of Inter-Ictal Discharging Reveal Epileptogenic Zone.

    PubMed

    Zhang, Luyan; Liang, Yi; Li, Fali; Sun, Hongbin; Peng, Wenjing; Du, Peishan; Si, Yajing; Song, Limeng; Yu, Liang; Xu, Peng

    2017-01-01

    The neuronal synchronous discharging may cause an epileptic seizure. Currently, most of the studies conducted to investigate the mechanism of epilepsy are based on EEGs or functional magnetic resonance imaging (fMRI) recorded during the ictal discharging or the resting-state, and few studies have probed into the dynamic patterns during the inter-ictal discharging that are much easier to record in clinical applications. Here, we propose a time-varying network analysis based on adaptive directed transfer function to uncover the dynamic brain network patterns during the inter-ictal discharging. In addition, an algorithm based on the time-varying outflow of information derived from the network analysis is developed to detect the epileptogenic zone. The analysis performed revealed the time-varying network patterns during different stages of inter-ictal discharging; the epileptogenic zone was activated prior to the discharge onset then worked as the source to propagate the activity to other brain regions. Consistence between the epileptogenic zones detected by our proposed approach and the actual epileptogenic zones proved that time-varying network analysis could not only reveal the underlying neural mechanism of epilepsy, but also function as a useful tool in detecting the epileptogenic zone based on the EEGs in the inter-ictal discharging.

  10. Work-related behavior and experience patterns of entrepreneurs compared to teachers and physicians.

    PubMed

    Voltmer, Edgar; Spahn, Claudia; Schaarschmidt, Uwe; Kieschke, Ulf

    2011-06-01

    This study examined the status of health-related behavior and experience patterns of entrepreneurs in comparison with teachers and physicians to identify specific health risks and resources. Entrepreneurs (n = 632), teachers (n = 5,196), and physicians (n = 549) were surveyed in a cross-sectional design. The questionnaire Work-related Behavior and Experience Patterns (AVEM) was used for all professions and, in addition, two scales (health prevention and self-confidence) from the Checklist for Entrepreneurs in the sample of entrepreneurs. The largest proportion of the entrepreneurs (45%) presented with a healthy pattern (compared with 18.4% teachers and 18.3% physicians). Thirty-eight percent of entrepreneurs showed a risk pattern of overexertion and stress, followed by teachers (28.9%) and physicians (20.6%). Unambitious or burnout patterns were seen in only 9.3/8.2% of entrepreneurs, respectively, and 25.3/27.3% of teachers, and 39.6/21.5% of physicians. While the distribution of patterns in teachers and physicians differed significantly between genders, a gender difference was not found among entrepreneurs. Entrepreneurs with the risk pattern of overexertion scored significantly (P < 0.01) lower in self-confidence and health care than those with the healthy pattern. The development of a successful enterprise depends, in part, on the health of the entrepreneur. The large proportion of entrepreneurs with the healthy pattern irrespective of gender may support the notion that self-selection effects of healthy individuals in this special career might be important. At the same time, a large proportion was at risk for overexertion and might benefit from measures to cope with professional demands and stress and promote a healthy behavior pattern.

  11. The importance of employment status in determining exit rates from nursing.

    PubMed

    Daniels, Frieda; Laporte, Audrey; Lemieux-Charles, Louise; Baumann, Andrea; Onate, Kanecy; Deber, Raisa

    2012-01-01

    To mitigate nurse shortages, health care decision makers tend to employ retention strategies that assume nurses employed in full-time, part-time, or casual positions and working in different sectors have similar preferences for work. However, this assumption has not been validated in the literature. The relationship between a nurse's propensity to exit the nurse profession in Ontario and employment status was explored by building an extended Cox Proportional Hazards Regression Model using a counting process technique. The differential exit patterns between part-time and casual nurses suggest that the common practice of treating part-time and casual nurses as equivalent is misleading. Health care decision makers should consider nurse retention strategies specifically targeting casual nurses because this segment of the profession is at the greatest risk of leaving. Nurse executives and nurse managers should investigate the different work preferences of part-time and casual nurses to devise tailored rather than "one-size fits all" nurse retention strategies to retain casual nurses.

  12. Patterns of Change in Adolescent Dating Victimization and Aggression During Middle School.

    PubMed

    Goncy, Elizabeth A; Farrell, Albert D; Sullivan, Terri N

    2018-03-01

    Although mounting evidence suggests dating victimization and aggression begin in early adolescence, little work has examined the pattern of these behaviors across this age. This longitudinal study examined trajectories of dating victimization and aggression across middle school using 12 waves of data. A sample of early adolescents (N = 1369, 52.3% girls; 83% African American; 15% Hispanic or Latino) residing in an urban, economically disadvantaged area participated in this study. Youth completed measures of dating victimization and aggression quarterly across the 3 years of middle school. Although results indicated a general trend of increasing dating victimization and aggression across middle school, variation existed for boys and girls. Specifically, girls showed increasing patterns of both, whereas boys remained relatively stable across time. Dating victimization and aggression were also highly correlated across time. These findings support the implementation and refinement of prevention programming aimed at preventing and reducing dating aggression and victimization in middle school.

  13. Model for screened, charge-regulated electrostatics of an eye lens protein: Bovine gammaB-crystallin

    PubMed Central

    Wahle, Christopher W.; Martini, K. Michael; Hollenbeck, Dawn M.; Langner, Andreas; Ross, David S.; Hamilton, John F.; Thurston, George M.

    2018-01-01

    We model screened, site-specific charge regulation of the eye lens protein bovine gammaB-crystallin (γ B) and study the probability distributions of its proton occupancy patterns. Using a simplified dielectric model, we solve the linearized Poisson-Boltzmann equation to calculate a 54 × 54 work-of-charging matrix, each entry being the modeled voltage at a given titratable site, due to an elementary charge at another site. The matrix quantifies interactions within patches of sites, including γB charge pairs. We model intrinsic pK values that would occur hypothetically in the absence of other charges, with use of experimental data on the dependence of pK values on aqueous solution conditions, the dielectric model, and literature values. We use Monte Carlo simulations to calculate a model grand-canonical partition function that incorporates both the work-of-charging and the intrinsic pK values for isolated γB molecules and we calculate the probabilities of leading proton occupancy configurations, for 4 < pH < 8 and Debye screening lengths from 6 to 20 Å. We select the interior dielectric value to model γB titration data. At pH 7.1 and Debye length 6.0 Å, on a given γB molecule the predicted top occupancy pattern is present nearly 20% of the time, and 90% of the time one or another of the first 100 patterns will be present. Many of these occupancy patterns differ in net charge sign as well as in surface voltage profile. We illustrate how charge pattern probabilities deviate from the multinomial distribution that would result from use of effective pK values alone and estimate the extents to which γB charge pattern distributions broaden at lower pH and narrow as ionic strength is lowered. These results suggest that for accurate modeling of orientation-dependent γB-γB interactions, consideration of numerous pairs of proton occupancy patterns will be needed. PMID:29346981

  14. Model for screened, charge-regulated electrostatics of an eye lens protein: Bovine gammaB-crystallin.

    PubMed

    Wahle, Christopher W; Martini, K Michael; Hollenbeck, Dawn M; Langner, Andreas; Ross, David S; Hamilton, John F; Thurston, George M

    2017-09-01

    We model screened, site-specific charge regulation of the eye lens protein bovine gammaB-crystallin (γB) and study the probability distributions of its proton occupancy patterns. Using a simplified dielectric model, we solve the linearized Poisson-Boltzmann equation to calculate a 54×54 work-of-charging matrix, each entry being the modeled voltage at a given titratable site, due to an elementary charge at another site. The matrix quantifies interactions within patches of sites, including γB charge pairs. We model intrinsic pK values that would occur hypothetically in the absence of other charges, with use of experimental data on the dependence of pK values on aqueous solution conditions, the dielectric model, and literature values. We use Monte Carlo simulations to calculate a model grand-canonical partition function that incorporates both the work-of-charging and the intrinsic pK values for isolated γB molecules and we calculate the probabilities of leading proton occupancy configurations, for 4

  15. Model for screened, charge-regulated electrostatics of an eye lens protein: Bovine gammaB-crystallin

    NASA Astrophysics Data System (ADS)

    Wahle, Christopher W.; Martini, K. Michael; Hollenbeck, Dawn M.; Langner, Andreas; Ross, David S.; Hamilton, John F.; Thurston, George M.

    2017-09-01

    We model screened, site-specific charge regulation of the eye lens protein bovine gammaB-crystallin (γ B ) and study the probability distributions of its proton occupancy patterns. Using a simplified dielectric model, we solve the linearized Poisson-Boltzmann equation to calculate a 54 ×54 work-of-charging matrix, each entry being the modeled voltage at a given titratable site, due to an elementary charge at another site. The matrix quantifies interactions within patches of sites, including γ B charge pairs. We model intrinsic p K values that would occur hypothetically in the absence of other charges, with use of experimental data on the dependence of p K values on aqueous solution conditions, the dielectric model, and literature values. We use Monte Carlo simulations to calculate a model grand-canonical partition function that incorporates both the work-of-charging and the intrinsic p K values for isolated γ B molecules and we calculate the probabilities of leading proton occupancy configurations, for 4

  16. Patterns of task and network actions performed by navigators to facilitate cancer care.

    PubMed

    Clark, Jack A; Parker, Victoria A; Battaglia, Tracy A; Freund, Karen M

    2014-01-01

    Patient navigation is a widely implemented intervention to facilitate access to care and reduce disparities in cancer care, but the activities of navigators are not well characterized. The aim of this study is to describe what patient navigators actually do and explore patterns of activity that clarify the roles they perform in facilitating cancer care. We conducted field observations of nine patient navigation programs operating in diverse health settings of the national patient navigation research program, including 34 patient navigators, each observed an average of four times. Trained observers used a structured observation protocol to code as they recorded navigator actions and write qualitative field notes capturing all activities in 15-minute intervals during observations ranging from 2 to 7 hours; yielding a total of 133 observations. Rates of coded activity were analyzed using numerical cluster analysis of identified patterns, informed by qualitative analysis of field notes. Six distinct patterns of navigator activity were identified, which differed most relative to how much time navigators spent directly interacting with patients and how much time they spent dealing with medical records and documentation tasks. Navigator actions reveal a complex set of roles in which navigators both provide the direct help to patients denoted by their title and also carry out a variety of actions that function to keep the health system operating smoothly. Working to navigate patients through complex health services entails working to repair the persistent challenges of health services that can render them inhospitable to patients. The organizations that deploy navigators might learn from navigators' efforts and explore alternative approaches, structures, or systems of care in addressing both the barriers patients face and the complex solutions navigators create in helping patients.

  17. Assessing the degree of plug flow in oxidation flow reactors (OFRs): a study on a potential aerosol mass (PAM) reactor

    NASA Astrophysics Data System (ADS)

    Mitroo, Dhruv; Sun, Yujian; Combest, Daniel P.; Kumar, Purushottam; Williams, Brent J.

    2018-03-01

    Oxidation flow reactors (OFRs) have been developed to achieve high degrees of oxidant exposures over relatively short space times (defined as the ratio of reactor volume to the volumetric flow rate). While, due to their increased use, attention has been paid to their ability to replicate realistic tropospheric reactions by modeling the chemistry inside the reactor, there is a desire to customize flow patterns. This work demonstrates the importance of decoupling tracer signal of the reactor from that of the tubing when experimentally obtaining these flow patterns. We modeled the residence time distributions (RTDs) inside the Washington University Potential Aerosol Mass (WU-PAM) reactor, an OFR, for a simple set of configurations by applying the tank-in-series (TIS) model, a one-parameter model, to a deconvolution algorithm. The value of the parameter, N, is close to unity for every case except one having the highest space time. Combined, the results suggest that volumetric flow rate affects mixing patterns more than use of our internals. We selected results from the simplest case, at 78 s space time with one inlet and one outlet, absent of baffles and spargers, and compared the experimental F curve to that of a computational fluid dynamics (CFD) simulation. The F curves, which represent the cumulative time spent in the reactor by flowing material, match reasonably well. We value that the use of a small aspect ratio reactor such as the WU-PAM reduces wall interactions; however sudden apertures introduce disturbances in the flow, and suggest applying the methodology of tracer testing described in this work to investigate RTDs in OFRs to observe the effect of modified inlets, outlets and use of internals prior to application (e.g., field deployment vs. laboratory study).

  18. A Canadian perspective on anterior cervical discectomies: practice patterns and preferences

    PubMed Central

    Bennardo, Michael; Farrokhyar, Forough; Martyniuk, Amanda; Reddy, Kesava

    2018-01-01

    Background The purpose of this study is to elucidate the current practice patterns of Canadian neurosurgeons with regards to anterior cervical discectomy (ACD). Methods A one-page questionnaire was sent out using SurveyMonkey to all neurosurgeon members of the Canadian Neurological Sciences Federation (CNSF). End points were surgeon preference for ACD surgical method, graft source, the length of collar usage and the recommended time before returning to work. Results Response rate was 74.0%. Of the responders, 75.0% performed single level ACD and 18.3% had completed spine fellowships. The majority (68.2%) chose ACD with fusion and plating (ACDFP) as their preferred method with allograft being the most popular choice of fusion material (44.3%). Most of the respondents did not prescribe collars (60.9%) and when they did, hard collar was prescribed most often (76.9%) and AspenTM collar was the most popular choice (67.7%). The majority of surgeons chose ‘other’ as their response for length of time for collar use (40.0%) while allowing them to take their collars off at night (78.1%). Most of the surgeons recommended physiotherapy post-operatively (58.1%) and time to physiotherapy was 6–8 weeks. Recommended back to work time was 6 weeks for 44.9% of respondents. In the cross analysis, surgeons who performed ACDF were more likely to prescribe collars (50%, P=0.01) versus surgeons who performed ACDFP (21.7%, P=0.01). Conclusions Our survey is an up to date description of current practice patterns for ACD amongst Canadian neurosurgeons. PMID:29732425

  19. a Three-Step Spatial-Temporal Clustering Method for Human Activity Pattern Analysis

    NASA Astrophysics Data System (ADS)

    Huang, W.; Li, S.; Xu, S.

    2016-06-01

    How people move in cities and what they do in various locations at different times form human activity patterns. Human activity pattern plays a key role in in urban planning, traffic forecasting, public health and safety, emergency response, friend recommendation, and so on. Therefore, scholars from different fields, such as social science, geography, transportation, physics and computer science, have made great efforts in modelling and analysing human activity patterns or human mobility patterns. One of the essential tasks in such studies is to find the locations or places where individuals stay to perform some kind of activities before further activity pattern analysis. In the era of Big Data, the emerging of social media along with wearable devices enables human activity data to be collected more easily and efficiently. Furthermore, the dimension of the accessible human activity data has been extended from two to three (space or space-time) to four dimensions (space, time and semantics). More specifically, not only a location and time that people stay and spend are collected, but also what people "say" for in a location at a time can be obtained. The characteristics of these datasets shed new light on the analysis of human mobility, where some of new methodologies should be accordingly developed to handle them. Traditional methods such as neural networks, statistics and clustering have been applied to study human activity patterns using geosocial media data. Among them, clustering methods have been widely used to analyse spatiotemporal patterns. However, to our best knowledge, few of clustering algorithms are specifically developed for handling the datasets that contain spatial, temporal and semantic aspects all together. In this work, we propose a three-step human activity clustering method based on space, time and semantics to fill this gap. One-year Twitter data, posted in Toronto, Canada, is used to test the clustering-based method. The results show that the approximate 55% spatiotemporal clusters distributed in different locations can be eventually grouped as the same type of clusters with consideration of semantic aspect.

  20. Patterns of Activity in A Global Model of A Solar Active Region

    NASA Technical Reports Server (NTRS)

    Bradshaw, S. J.; Viall, N. M.

    2016-01-01

    In this work we investigate the global activity patterns predicted from a model active region heated by distributions of nanoflares that have a range of frequencies. What differs is the average frequency of the distributions. The activity patterns are manifested in time lag maps of narrow-band instrument channel pairs. We combine hydrodynamic and forward modeling codes with a magnetic field extrapolation to create a model active region and apply the time lag method to synthetic observations. Our aim is not to reproduce a particular set of observations in detail, but to recover some typical properties and patterns observed in active regions. Our key findings are the following. (1) Cooling dominates the time lag signature and the time lags between the channel pairs are generally consistent with observed values. (2) Shorter coronal loops in the core cool more quickly than longer loops at the periphery. (3) All channel pairs show zero time lag when the line of sight passes through coronal loop footpoints. (4) There is strong evidence that plasma must be re-energized on a timescale comparable to the cooling timescale to reproduce the observed coronal activity, but it is likely that a relatively broad spectrum of heating frequencies are operating across active regions. (5) Due to their highly dynamic nature, we find nanoflare trains produce zero time lags along entire flux tubes in our model active region that are seen between the same channel pairs in observed active regions.

  1. Analysis of the physical activity patterns of a rural Afrikaner population in the south-western Cape.

    PubMed

    Noakes, T D; Benade, A J; Jooste, P L; van Zyl, F

    1986-06-21

    To determine whether low levels of energy expenditure at work or in leisure-time might contribute to the high prevalence of coronary heart disease among white rural Afrikaners, 7188 whites of both sexes in three rural communities were questioned about their physical activities. From these data, the percentage of the population at different ages participating in sedentary, moderate or vigorous activity at work or light, moderate or vigorous leisure-time activity was calculated. Total energy expenditure at work or in leisure-time was also calculated. At all ages, less than 1% of both men and women performed workday activities requiring high energy output. Beginning after the age of 24 years, there was a dramatic fall in the percentage of both men and women participating in either moderate or vigorous leisure-time physical activity. After the age of 44 years, less than 26% of men and 16% of women exceeded the coronary 'protective threshold' of 8400 kJ leisure-time energy expenditure per week. Thus the population studied is characterized by very low levels of energy expenditure particularly at work, but also during leisure-time.

  2. Stable and Dynamic Coding for Working Memory in Primate Prefrontal Cortex

    PubMed Central

    Watanabe, Kei; Funahashi, Shintaro; Stokes, Mark G.

    2017-01-01

    Working memory (WM) provides the stability necessary for high-level cognition. Influential theories typically assume that WM depends on the persistence of stable neural representations, yet increasing evidence suggests that neural states are highly dynamic. Here we apply multivariate pattern analysis to explore the population dynamics in primate lateral prefrontal cortex (PFC) during three variants of the classic memory-guided saccade task (recorded in four animals). We observed the hallmark of dynamic population coding across key phases of a working memory task: sensory processing, memory encoding, and response execution. Throughout both these dynamic epochs and the memory delay period, however, the neural representational geometry remained stable. We identified two characteristics that jointly explain these dynamics: (1) time-varying changes in the subpopulation of neurons coding for task variables (i.e., dynamic subpopulations); and (2) time-varying selectivity within neurons (i.e., dynamic selectivity). These results indicate that even in a very simple memory-guided saccade task, PFC neurons display complex dynamics to support stable representations for WM. SIGNIFICANCE STATEMENT Flexible, intelligent behavior requires the maintenance and manipulation of incoming information over various time spans. For short time spans, this faculty is labeled “working memory” (WM). Dominant models propose that WM is maintained by stable, persistent patterns of neural activity in prefrontal cortex (PFC). However, recent evidence suggests that neural activity in PFC is dynamic, even while the contents of WM remain stably represented. Here, we explored the neural dynamics in PFC during a memory-guided saccade task. We found evidence for dynamic population coding in various task epochs, despite striking stability in the neural representational geometry of WM. Furthermore, we identified two distinct cellular mechanisms that contribute to dynamic population coding. PMID:28559375

  3. Extreme ultraviolet patterning of tin-oxo cages

    NASA Astrophysics Data System (ADS)

    Haitjema, Jarich; Zhang, Yu; Vockenhuber, Michaela; Kazazis, Dimitrios; Ekinci, Yasin; Brouwer, Albert M.

    2017-07-01

    We report on the extreme ultraviolet (EUV) patterning performance of tin-oxo cages. These cage molecules were already known to function as a negative tone photoresist for EUV radiation, but in this work, we significantly optimized their performance. Our results show that sensitivity and resolution are only meaningful photoresist parameters if the process conditions are optimized. We focus on contrast curves of the materials using large area EUV exposures and patterning of the cages using EUV interference lithography. It is shown that baking steps, such as postexposure baking, can significantly affect both the sensitivity and contrast in the open-frame experiments as well as the patterning experiments. A layer thickness increase reduced the necessary dose to induce a solubility change but decreased the patterning quality. The patterning experiments were affected by minor changes in processing conditions such as an increased rinsing time. In addition, we show that the anions of the cage can influence the sensitivity and quality of the patterning, probably through their effect on physical properties of the materials.

  4. Stress in Professional Classes: Causes, Manifestations, Coping.

    ERIC Educational Resources Information Center

    Endres, Fred F.

    1992-01-01

    Investigates whether students in professional journalism and mass communication classes experience class-related stress, what factors contribute to the stress, and whether that stress changes over time. Finds that students perceive stress in their professional course work, and reveals general stress patterns over the 15-week semester. (SR)

  5. Civic Engagement Patterns of Undocumented Mexican Students

    ERIC Educational Resources Information Center

    Perez, William; Espinoza, Roberta; Ramos, Karina; Coronado, Heidi; Cortes, Richard

    2010-01-01

    This study examined the civic engagement of undocumented Mexican students. Civic engagement was defined as providing a social service, activism, tutoring, and functionary work. Survey data results (n = 126) suggest that despite high feelings of rejection because of their undocumented status, part-time employment, and household responsibilities,…

  6. Dynamics of salivary proteins and metabolites during extreme endurance sports - a case study.

    PubMed

    Zauber, Henrik; Mosler, Stephan; von Heßberg, Andreas; Schulze, Waltraud X

    2012-07-01

    As noninvasively accessible body fluid, saliva is of growing interest in diagnostics. To exemplify the diagnostic potential of saliva, we used a mass spectrometry-based approach to gain insights into adaptive physiological processes underlying long-lasting endurance work load in a case study. Saliva was collected from male and female athlete at four diurnal time points throughout a 1060 km nonstop cycling event. Total sampling time covered 180 h comprising 62 h of endurance cycling as well as reference samples taken over 3 days before the event, and over 2 days after. Altogether, 1405 proteins and 62 metabolites were identified in these saliva samples, of which 203 could be quantified across the majority of the sampling time points. Many proteins show clear diurnal abundance patterns in saliva. In many cases, these patterns were disturbed and altered by the long-term endurance stress. During the stress phase, metabolites of energy mobilization, such as creatinine and glucose were of high abundance, as well as metabolites with antioxidant functions. Lysozyme, amylase, and proteins with redox-regulatory function showed significant increase in average abundance during work phase compared to rest or recovery phase. The recovery phase was characterized by an increased abundance of immunoglobulins. Our work exemplifies the application of high-throughput technologies to understand adaptive processes in human physiology. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Mistimed food intake and sleep alters 24-hour time-of-day patterns of the human plasma proteome.

    PubMed

    Depner, Christopher M; Melanson, Edward L; McHill, Andrew W; Wright, Kenneth P

    2018-06-05

    Proteomics holds great promise for understanding human physiology, developing health biomarkers, and precision medicine. However, how much the plasma proteome varies with time of day and is regulated by the master circadian suprachiasmatic nucleus brain clock, assessed here by the melatonin rhythm, is largely unknown. Here, we assessed 24-h time-of-day patterns of human plasma proteins in six healthy men during daytime food intake and nighttime sleep in phase with the endogenous circadian clock (i.e., circadian alignment) versus daytime sleep and nighttime food intake out of phase with the endogenous circadian clock (i.e., circadian misalignment induced by simulated nightshift work). We identified 24-h time-of-day patterns in 573 of 1,129 proteins analyzed, with 30 proteins showing strong regulation by the circadian cycle. Relative to circadian alignment, the average abundance and/or 24-h time-of-day patterns of 127 proteins were altered during circadian misalignment. Altered proteins were associated with biological pathways involved in immune function, metabolism, and cancer. Of the 30 circadian-regulated proteins, the majority peaked between 1400 hours and 2100 hours, and these 30 proteins were associated with basic pathways involved in extracellular matrix organization, tyrosine kinase signaling, and signaling by receptor tyrosine-protein kinase erbB-2. Furthermore, circadian misalignment altered multiple proteins known to regulate glucose homeostasis and/or energy metabolism, with implications for altered metabolic physiology. Our findings demonstrate the circadian clock, the behavioral wake-sleep/food intake-fasting cycle, and interactions between these processes regulate 24-h time-of-day patterns of human plasma proteins and help identify mechanisms of circadian misalignment that may contribute to metabolic dysregulation.

  8. Estimation of Dynamic Sparse Connectivity Patterns From Resting State fMRI.

    PubMed

    Cai, Biao; Zille, Pascal; Stephen, Julia M; Wilson, Tony W; Calhoun, Vince D; Wang, Yu Ping

    2018-05-01

    Functional connectivity (FC) estimated from functional magnetic resonance imaging (fMRI) time series, especially during resting state periods, provides a powerful tool to assess human brain functional architecture in health, disease, and developmental states. Recently, the focus of connectivity analysis has shifted toward the subnetworks of the brain, which reveals co-activating patterns over time. Most prior works produced a dense set of high-dimensional vectors, which are hard to interpret. In addition, their estimations to a large extent were based on an implicit assumption of spatial and temporal stationarity throughout the fMRI scanning session. In this paper, we propose an approach called dynamic sparse connectivity patterns (dSCPs), which takes advantage of both matrix factorization and time-varying fMRI time series to improve the estimation power of FC. The feasibility of analyzing dynamic FC with our model is first validated through simulated experiments. Then, we use our framework to measure the difference between young adults and children with real fMRI data set from the Philadelphia Neurodevelopmental Cohort (PNC). The results from the PNC data set showed significant FC differences between young adults and children in four different states. For instance, young adults had reduced connectivity between the default mode network and other subnetworks, as well as hyperconnectivity within the visual system in states 1 and 3, and hypoconnectivity in state 2. Meanwhile, they exhibited temporal correlation patterns that changed over time within functional subnetworks. In addition, the dSCPs model indicated that older people tend to spend more time within a relatively connected FC pattern. Overall, the proposed method provides a valid means to assess dynamic FC, which could facilitate the study of brain networks.

  9. Local Material as a Character of Contemporary Interior Design in Indonesia

    NASA Astrophysics Data System (ADS)

    Susanto, Dalhar; Puti Angelia, Dini; Ningsih, Tria Amalia

    2017-12-01

    Excellent design needs to fulfill universal requirements (utility, aesthetic, ergonomic, durability, and safe). Besides of all the requirements, an excellent design has to be shown its distinctiveness, uniqueness, and identity. To create an excellent design, we can use one of locality approach, it means local material utilization. From time to time, the material is linking each other in unity with environment context, human, knowledge, culture, social, economy, user needs and material availability. The aspects are the important part to get the reflective identity and local values in architecture and interior design work in Indonesia. It can be proofed by some of the architecture and interior work precedent, like traditional or vernacular in Nusantara or contemporary interior design work from Indonesian designer who has recognized to promote the locality value. However interior design works in Indonesia cannot be shown the characteristic of Indonesia identity and locality currently, it is different than another country work, like Japan, Italy, or Scandinavia. Interior design work from these countries can be easily known with accentuating of characteristic their places, such as material, color, detail, or geometry pattern in the product that has been produced. Meanwhile, some of the region in Indonesia are tropical climate and brought about much of local material and it has potential to make a unique work which has the local identity. This paper will discuss the result of a searching potential of local material usefulness as interior design identity in Indonesia. This research is done by typology method, which means discover the presence of some of the architecture elements appears to be related material. The elements are the pattern, color, craftsmanship, building element, object, and type of material in some of the contemporary interior design work in Indonesia were considered superior and capable of lifting elements recognized locality.

  10. Promoting wellbeing in young unemployed adults: the importance of identifying meaningful patterns of time use.

    PubMed

    Scanlan, Justin Newton; Bundy, Anita C; Matthews, Lynda R

    2011-04-01

    This study set out to explore the differences in time use between 'unemployed', 'unemployed but in education' and part-time and full-time employed 18- to 25-year-old Australians. Unemployed individuals generally experience poor health and this may be related to the way they use their time. Activity-based interventions may be one health-promoting strategy. This knowledge is important for all occupational therapists, as many service users are likely to be unemployed. Time use of unemployed 18- to 25-year-olds (measured using the Modified Occupational Questionnaire) was compared with the time use of part- and full-time employed 18- to 25-year-olds (from the 2006 Australian Time Use Survey). Individuals in the 'unemployed' groups spent significantly less time engaged in work-related activities than their employed peers. This time was reallocated mainly to recreation and leisure and household work (for both men and women) and child care and sleeping (women only). Recreation and leisure activities were generally passive, home-based activities such as watching television or 'doing nothing'. Individuals in the 'unemployed but in education' groups also spent less time in employment-related activities, but the majority of this time was reallocated to education activities. Individuals in the 'unemployed' groups spent large amounts of time engaged in potentially non-directed use of time (e.g. watching television or 'doing nothing'). Such patterns of time use have previously been associated with poor health. To support the health of unemployed individuals more effectively, occupational therapy interventions must focus on enhancing the quality of time use for this population. © 2010 The Authors. Australian Occupational Therapy Journal © 2010 Australian Association of Occupational Therapists.

  11. Harmonic Fluxes and Electromagnetic Forces of Concentric Winding Brushless Permanent Magnet Motor

    NASA Astrophysics Data System (ADS)

    Ishibashi, Fuminori; Takemasa, Ryo; Matsushita, Makoto; Nishizawa, Takashi; Noda, Shinichi

    Brushless permanent magnet motors have been widely used in home applications and industrial fields. These days, high efficiency and low noise motors are demanded from the view point of environment. Electromagnetic noise and iron loss of the motor are produced by the harmonic fluxes and electromagnetic forces. However, order and space pattern of these have not been discussed in detail. In this paper, fluxes, electromagnetic forces and magneto-motive forces of brushless permanent magnet motors with concentric winding were analyzed analytically, experimentally and numerically. Time harmonic fluxes and time electromagnetic forces in the air gap were measured by search coils on the inner surface of the stator teeth and analyzed by FEM. Space pattern of time harmonic fluxes and time electromagnetic forces were worked out with experiments and FEM. Magneto motive forces due to concentric winding were analyzed with equations and checked by FEM.

  12. Within-couple specialisation in paid work: A long-term pattern? A dual trajectory approach to linking lives.

    PubMed

    Langner, Laura Antonia

    2015-06-01

    Research on the division of labour has mainly focussed on transitions between individuals' labour market states during the first years of parenthood. A common conclusion has been that couples specialize--women in unpaid and men in paid work--either due to gender ideologies or a comparative advantage in the labour market. But what happens later in life? The German Socio-Economic Panel now provides researchers with a continuous measure of working hours across decades of couples' lives, enabling a dual trajectory analysis to explore couples' long-term specialisation patterns. I focus on the career trajectories of West German couples, and specifically, due to the relatively low institutional and normative support for female employment during its members' early years, on the 1956-65 female birth cohort. Even in this setting and with a conservative estimate, a surprisingly small number of couples--only a fifth--adopt full specialisation in later life. A sizable proportion--a third--moves into dual full-time employment. This trend is even more common among highly educated couples: half of those couples move into dual full-time employment. I find that highly educated women are not only less likely to permanently specialise but also more likely to try working full-time, possibly because their partners' comparative advantages are lower. But despite high opportunity costs, 45% of highly educated parents never try to pursue a dual career either because of a satiation of material wants or because of low societal support for maternal employment. The latter phenomenon is further underscored by the finding that many couples' increase in working hours occurs only when a youngest child is a teenager. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Infraslow Electroencephalographic and Dynamic Resting State Network Activity.

    PubMed

    Grooms, Joshua K; Thompson, Garth J; Pan, Wen-Ju; Billings, Jacob; Schumacher, Eric H; Epstein, Charles M; Keilholz, Shella D

    2017-06-01

    A number of studies have linked the blood oxygenation level dependent (BOLD) signal to electroencephalographic (EEG) signals in traditional frequency bands (δ, θ, α, β, and γ), but the relationship between BOLD and its direct frequency correlates in the infraslow band (<1 Hz) has been little studied. Previously, work in rodents showed that infraslow local field potentials play a role in functional connectivity, particularly in the dynamic organization of large-scale networks. To examine the relationship between infraslow activity and network dynamics in humans, direct current (DC) EEG and resting state magnetic resonance imaging data were acquired simultaneously. The DC EEG signals were correlated with the BOLD signal in patterns that resembled resting state networks. Subsequent dynamic analysis showed that the correlation between DC EEG and the BOLD signal varied substantially over time, even within individual subjects. The variation in DC EEG appears to reflect the time-varying contribution of different resting state networks. Furthermore, some of the patterns of DC EEG and BOLD correlation are consistent with previous work demonstrating quasiperiodic spatiotemporal patterns of large-scale network activity in resting state. These findings demonstrate that infraslow electrical activity is linked to BOLD fluctuations in humans and that it may provide a basis for large-scale organization comparable to that observed in animal studies.

  14. Infraslow Electroencephalographic and Dynamic Resting State Network Activity

    PubMed Central

    Grooms, Joshua K.; Thompson, Garth J.; Pan, Wen-Ju; Billings, Jacob; Schumacher, Eric H.; Epstein, Charles M.

    2017-01-01

    Abstract A number of studies have linked the blood oxygenation level dependent (BOLD) signal to electroencephalographic (EEG) signals in traditional frequency bands (δ, θ, α, β, and γ), but the relationship between BOLD and its direct frequency correlates in the infraslow band (<1 Hz) has been little studied. Previously, work in rodents showed that infraslow local field potentials play a role in functional connectivity, particularly in the dynamic organization of large-scale networks. To examine the relationship between infraslow activity and network dynamics in humans, direct current (DC) EEG and resting state magnetic resonance imaging data were acquired simultaneously. The DC EEG signals were correlated with the BOLD signal in patterns that resembled resting state networks. Subsequent dynamic analysis showed that the correlation between DC EEG and the BOLD signal varied substantially over time, even within individual subjects. The variation in DC EEG appears to reflect the time-varying contribution of different resting state networks. Furthermore, some of the patterns of DC EEG and BOLD correlation are consistent with previous work demonstrating quasiperiodic spatiotemporal patterns of large-scale network activity in resting state. These findings demonstrate that infraslow electrical activity is linked to BOLD fluctuations in humans and that it may provide a basis for large-scale organization comparable to that observed in animal studies. PMID:28462586

  15. Not all hours are equal: could time be a social determinant of health?

    PubMed

    Strazdins, Lyndall; Welsh, Jennifer; Korda, Rosemary; Broom, Dorothy; Paolucci, Francesco

    2016-01-01

    Time can be thought of as a resource that people need for good health. Healthy behaviour, accessing health services, working, resting and caring all require time. Like other resources, time is socially shaped, but its relevance to health and health inequality is yet to be established. Drawing from sociology and political economy, we set out the theoretical basis for two measures of time relevant to contemporary, market-based societies. We measure amount of time spent on care and work (paid and unpaid) and the intensity of time, which refers to rushing, effort and speed. Using data from wave 9 (N = 9177) of the Household, Income and Labour Dynamics of Australia Survey we found that time poverty (> 80 h per week on care and work) and often or always rushing are barriers to physical activity and rushing is associated with poorer self-rated and mental health. Exploring their social patterning, we find that time-poor people have higher incomes and more time control. In contrast, rushing is linked to being a woman, lone parenthood, disability, lack of control and work-family conflicts. We supply a methodology to support quantitative investigations of time, and our findings underline time's dimensionality, social distribution and potential to influence health. © 2015 The Authors. Sociology of Health & Illness published by John Wiley & Sons Ltd on behalf of Foundation for SHIL.

  16. Comparative study on luminescence extraction strategies of LED by large-scale fabrication of nanopillar and nanohole structures

    NASA Astrophysics Data System (ADS)

    Guo, Wei; Li, Junmei; Sheikhi, Moheb; Jiang, Jie’an; Yang, Zhenhai; Li, Hongwei; Guo, Shiping; Sheng, Jiang; Sun, Jie; Bo, Baoxue; Ye, Jichun

    2018-06-01

    Light extraction and current injection are two important considerations in the development of high efficiency light-emitting-diodes (LEDs), but usually cannot be satisfied simultaneously in nanostructure patterned devices. In this work, we investigated near-UV LEDs with nanopillar and nanohole patterns to improve light extraction efficiency. Photoluminescence (PL) intensities were enhanced by 8.0 and 4.1 times for nanopillar and nanohole LEDs compared to that of planar LED. Nanopillar LED exhibits higher PL emission than that of the nanohole LED, attributing to a convex shape sidewall for more effective outward light scattering, and reduction of quantum-confined-stark-effect owing to strain relaxation. However, nanopillar LED exhibits lower electroluminescence intensity than the nanohole sample, which calls for further optimization in carrier distributions. Experimental results were further supported by near-field electric field simulations. This work demonstrates the difference in optical and electrical behaviors between the nanopillar and nanohole LEDs, paving the way for detailed understanding on luminescence extraction mechanisms of nanostructure patterned UV emitters.

  17. Work-related behaviour and experience pattern in nurses: impact on physical and mental health.

    PubMed

    Schulz, M; Damkröger, A; Voltmer, E; Löwe, B; Driessen, M; Ward, M; Wingenfeld, K

    2011-06-01

    Nursing is associated with high levels of emotional strain and heavy workloads. Changing working conditions raise the importance of investigating job satisfaction, stress and burnout and its consequences for nurses. The aim of the study was to investigate whether work-related behaviour and experience patterns are associated with mental and physical health status in nurses. A sample of 356 nurses in four German hospitals were interviewed using questionnaires regarding work-related behaviour and experience patterns, work stress, depression, anxiety and physical symptoms ('Work-related Behaviour and Experience Pattern'--AVEM and ERI). The main result of this study is that unhealthy work-related behaviour and experience patterns (i.e. the excessive ambitious type and the resigned type) are associated with reduced mental and physical health. Preventive, as well as intervention, strategies are needed that focus both on the individual as well as on working conditions. © 2011 Blackwell Publishing.

  18. Effectively identifying user profiles in network and host metrics

    NASA Astrophysics Data System (ADS)

    Murphy, John P.; Berk, Vincent H.; Gregorio-de Souza, Ian

    2010-04-01

    This work presents a collection of methods that is used to effectively identify users of computers systems based on their particular usage of the software and the network. Not only are we able to identify individual computer users by their behavioral patterns, we are also able to detect significant deviations in their typical computer usage over time, or compared to a group of their peers. For instance, most people have a small, and relatively unique selection of regularly visited websites, certain email services, daily work hours, and typical preferred applications for mandated tasks. We argue that these habitual patterns are sufficiently specific to identify fully anonymized network users. We demonstrate that with only a modest data collection capability, profiles of individual computer users can be constructed so as to uniquely identify a profiled user from among their peers. As time progresses and habits or circumstances change, the methods presented update each profile so that changes in user behavior can be reliably detected over both abrupt and gradual time frames, without losing the ability to identify the profiled user. The primary benefit of our methodology allows one to efficiently detect deviant behaviors, such as subverted user accounts, or organizational policy violations. Thanks to the relative robustness, these techniques can be used in scenarios with very diverse data collection capabilities, and data privacy requirements. In addition to behavioral change detection, the generated profiles can also be compared against pre-defined examples of known adversarial patterns.

  19. Analysis of work zone rear-end crash risk for different vehicle-following patterns.

    PubMed

    Weng, Jinxian; Meng, Qiang; Yan, Xuedong

    2014-11-01

    This study evaluates rear-end crash risk associated with work zone operations for four different vehicle-following patterns: car-car, car-truck, truck-car and truck-truck. The deceleration rate to avoid the crash (DRAC) is adopted to measure work zone rear-end crash risk. Results show that the car-truck following pattern has the largest rear-end crash risk, followed by truck-truck, truck-car and car-car patterns. This implies that it is more likely for a car which is following a truck to be involved in a rear-end crash accident. The statistical test results further confirm that rear-end crash risk is statistically different between any two of the four patterns. We therefore develop a rear-end crash risk model for each vehicle-following pattern in order to examine the relationship between rear-end crash risk and its influencing factors, including lane position, the heavy vehicle percentage, lane traffic flow and work intensity which can be characterized by the number of lane reductions, the number of workers and the amount of equipment at the work zone site. The model results show that, for each pattern, there will be a greater rear-end crash risk in the following situations: (i) heavy work intensity; (ii) the lane adjacent to work zone; (iii) a higher proportion of heavy vehicles and (iv) greater traffic flow. However, the effects of these factors on rear-end crash risk are found to vary according to the vehicle-following patterns. Compared with the car-car pattern, lane position has less effect on rear-end crash risk in the car-truck pattern. The effect of work intensity on rear-end crash risk is also reduced in the truck-car pattern. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Post-Fordist reconfigurations of gender, work and life: theory and practice.

    PubMed

    Gray, Breda; Ciolfi, Luigina; de Carvalho, Aparecido Fabiano Pinatti; D'Andrea, Anthony; Wixted, Lisa

    2017-12-01

    Based on an in-depth study with 56 informants (25 women and 31 men), across the ICT (information and communication technology), creative and academic sectors in one city/regional hub in Ireland, this article investigates the so-called revolution in work/life practices associated with the post-Fordist labour processes of the Knowledge Economy from the perspectives of workers themselves. Recent theorizations of post-Fordist work patterns emphasize a rearranging of work and life place boundaries; a reconfiguring of work and life time boundaries; and a dissolving of the gendered boundaries of work and life (production and social reproduction) (Adkins and Dever ; Morini and Fumagalli ; Gill and Pratt ; Weeks ; Hardt and Negri ). Our findings suggest that, instead of dissolving boundaries, workers constantly struggle to draw boundaries between what counts as work and as life, and that this varies primarily in relation to gender and stage in a gendered life trajectory. Work extensification is compensated for via a perceived freedom to shape one's own life, which is articulated in terms of individualized boundary-drawing. While younger men embraced 'always on' work, they also articulated anxieties about how these work habits might interfere with family aspirations. This was also true for younger women who also struggled to make time for life in the present. For mothers, boundary drawing was articulated as a necessity but was framed more in terms of personal choice by fathers. Although all participants distinguished between paid work and life as distinct sites of value, boundaries were individually drawn and resist any easy mapping of masculinity and femininity onto the domains of work and life. Instead, we argue that it is the process of boundary drawing that reveals gendered patterns. The personalized struggles of these relatively privileged middle-class workers centre on improving the quality of their lives, but raise important questions about the political possibilities within and beyond the world of post-Fordist labour. © London School of Economics and Political Science 2017.

  1. Circadian and ultradian rhythms in the feeding behaviour and nutrient intakes of oil refinery operators with shift-work every 3--4 days.

    PubMed

    Reinberg, A; Migraine, C; Apfelbaum, M; Brigant, L; Ghata, J; Vieux, N; Laporte, A; Nicolai

    1979-03-01

    Seven healthy adult men, five shift-workers and two non-shift-workers (from 21 to 36 years; mean = 26.4) volunteered to record what and when they ate, both at work and at home, every day, during eight consecutive weeks (Oct. - Dec. 1974). 1) All the subjects maintained the timing of main-meal (lunch and supper) during all shifts. 2) The major intake of protein and lipid was concentrated on the two main meals during all shifts. 3) Only the pattern of carbohydrate intake was modified by the shift-work: e.g. night-shift is associated with nibbling behaviour. 4) However, shift-work and in particular the occurence of nibbling behaviour did not result in change either in the mean 24 h caloric intake, or in the percentage of protein calories. 5) The comparison between the constancy of the timing of major meals and the shift of the timing of circadian rhythm acrophases of the 5 shift-workers leads to conclude that meal timing had a poor synchronizing effect, if any.

  2. Collective iteration behavior for online social networks

    NASA Astrophysics Data System (ADS)

    Liu, Jian-Guo; Li, Ren-De; Guo, Qiang; Zhang, Yi-Cheng

    2018-06-01

    Understanding the patterns of collective behavior in online social network (OSNs) is critical to expanding the knowledge of human behavior and tie relationship. In this paper, we investigate a specific pattern called social signature in Facebook and Wiki users' online communication behaviors, capturing the distribution of frequency of interactions between different alters over time in the ego network. The empirical results show that there are robust social signatures of interactions no matter how friends change over time, which indicates that a stable commutation pattern exists in online communication. By comparing a random null model, we find the that commutation pattern is heterogeneous between ego and alters. Furthermore, in order to regenerate the pattern of the social signature, we present a preferential interaction model, which assumes that new users intend to look for the old users with strong ties while old users have tendency to interact with new friends. The experimental results show that the presented model can reproduce the heterogeneity of social signature by adjusting 2 parameters, the number of communicating targets m and the max number of interactions n, for Facebook users, m = n = 5, for Wiki users, m = 2 and n = 8. This work helps in deeply understanding the regularity of social signature.

  3. A longitudinal comparison of age patterns and rates of suicide in Hong Kong, Taiwan and Japan and two Western countries.

    PubMed

    Snowdon, John; Chen, Ying-Yeh; Zhong, Baoliang; Yamauchi, Takashi

    2018-01-01

    Suicide data relating to 1979-2014 were obtained from three East Asian jurisdictions (Taiwan, Hong Kong, Japan) and two 'Western' countries (Australia, New Zealand). Rates and age patterns of suicide have changed markedly since 1979. Graphs of these patterns largely remained either upward-sloping, bimodal or flat (uniform) over the 36 years, male commonly differing from female, and East Asian patterns more like each other than those of the Western countries. Japan's male middle-aged suicide rate reached a peak in 1999-2003, which, like increased rates among working age males in Hong Kong and Taiwan, has been attributed largely to consequences of Asian financial crises. Male to female ratios of suicide rates have remained higher in the Western countries, but late life suicide rates have decreased to varying extents in all five jurisdictions. Identifying reasons for differences between jurisdictions in their suicide rates and patterns at particular times, and over time, is likely to point to factors (period, cohort, psychosocial or cultural) that protect against or foster suicidal ideation. This avenue of research may assist in identifying ways of preventing suicide. Copyright © 2017. Published by Elsevier B.V.

  4. The Cluster Variation Method: A Primer for Neuroscientists.

    PubMed

    Maren, Alianna J

    2016-09-30

    Effective Brain-Computer Interfaces (BCIs) require that the time-varying activation patterns of 2-D neural ensembles be modelled. The cluster variation method (CVM) offers a means for the characterization of 2-D local pattern distributions. This paper provides neuroscientists and BCI researchers with a CVM tutorial that will help them to understand how the CVM statistical thermodynamics formulation can model 2-D pattern distributions expressing structural and functional dynamics in the brain. The premise is that local-in-time free energy minimization works alongside neural connectivity adaptation, supporting the development and stabilization of consistent stimulus-specific responsive activation patterns. The equilibrium distribution of local patterns, or configuration variables , is defined in terms of a single interaction enthalpy parameter ( h ) for the case of an equiprobable distribution of bistate (neural/neural ensemble) units. Thus, either one enthalpy parameter (or two, for the case of non-equiprobable distribution) yields equilibrium configuration variable values. Modeling 2-D neural activation distribution patterns with the representational layer of a computational engine, we can thus correlate variational free energy minimization with specific configuration variable distributions. The CVM triplet configuration variables also map well to the notion of a M = 3 functional motif. This paper addresses the special case of an equiprobable unit distribution, for which an analytic solution can be found.

  5. The Cluster Variation Method: A Primer for Neuroscientists

    PubMed Central

    Maren, Alianna J.

    2016-01-01

    Effective Brain–Computer Interfaces (BCIs) require that the time-varying activation patterns of 2-D neural ensembles be modelled. The cluster variation method (CVM) offers a means for the characterization of 2-D local pattern distributions. This paper provides neuroscientists and BCI researchers with a CVM tutorial that will help them to understand how the CVM statistical thermodynamics formulation can model 2-D pattern distributions expressing structural and functional dynamics in the brain. The premise is that local-in-time free energy minimization works alongside neural connectivity adaptation, supporting the development and stabilization of consistent stimulus-specific responsive activation patterns. The equilibrium distribution of local patterns, or configuration variables, is defined in terms of a single interaction enthalpy parameter (h) for the case of an equiprobable distribution of bistate (neural/neural ensemble) units. Thus, either one enthalpy parameter (or two, for the case of non-equiprobable distribution) yields equilibrium configuration variable values. Modeling 2-D neural activation distribution patterns with the representational layer of a computational engine, we can thus correlate variational free energy minimization with specific configuration variable distributions. The CVM triplet configuration variables also map well to the notion of a M = 3 functional motif. This paper addresses the special case of an equiprobable unit distribution, for which an analytic solution can be found. PMID:27706022

  6. Opting Out and Leaning In: The Life Course Employment Profiles of Early Baby Boom Women in the United States.

    PubMed

    García-Manglano, Javier

    2015-12-01

    Most literature on female employment focuses on the intersection between women's labor supply and family events such as marriage, divorce, or childbearing. Even when using longitudinal data and methods, most studies estimate average net effects over time and assume homogeneity among women. Less is known about diversity in women's cumulative work patterns over the long run. Using group-based trajectory analysis, I model the employment trajectories of early Baby Boom women in the United States from ages 20 to 54. I find that women in this cohort can be classified in four ideal-type groups: those who were consistently detached from the labor force (21 %), those who gradually increased their market attachment (27 %), those who worked intensely in young adulthood but dropped out of the workforce after midlife (13 %), and those who were steadily employed across midlife (40 %). I then explore a variety of traits associated with membership in each of these groups. I find that (1) the timing of family events (marriage, fertility) helps to distinguish between groups with weak or strong attachment to the labor force in early adulthood; (2) external constraints (workplace discrimination, husband's opposition to wife's work, ill health) explain membership in groups that experienced work trajectory reversals; and (3) individual preferences influence labor supply across women's life course. This analysis reveals a high degree of complexity in women's lifetime working patterns, highlighting the need to understand women's labor supply as a fluid process.

  7. The course of the working alliance during virtual reality and exposure group therapy for social anxiety disorder.

    PubMed

    Ngai, Irene; Tully, Erin C; Anderson, Page L

    2015-03-01

    Psychoanalytic theory and some empirical research suggest the working alliance follows a "rupture and repair" pattern over the course of therapy, but given its emphasis on collaboration, cognitive behavioral therapy may yield a different trajectory. The current study compares the trajectory of the working alliance during two types of cognitive behavioral therapy for social anxiety disorder - virtual reality exposure therapy (VRE) and exposure group therapy (EGT), one of which (VRE) has been proposed to show lower levels of working alliance due to the physical barriers posed by the technology (e.g. no eye contact with therapist during exposure). Following randomization, participants (N = 63) diagnosed with social anxiety disorder received eight sessions of manualized EGT or individual VRE and completed a standardized self-report measure of working alliance after each session. Hierarchical linear modeling showed overall high levels of working alliance that changed in rates of growth over time; that is, increases in working alliance scores were steeper at the beginning of therapy and slowed towards the end of therapy. There were no differences in working alliance between the two treatment groups. Results neither support a rupture/repair pattern nor the idea that the working alliance is lower for VRE participants. Findings are consistent with the idea that different therapeutic approaches may yield different working alliance trajectories.

  8. Comparison of accelerometer-measured sedentary behavior, and light- and moderate-to-vigorous-intensity physical activity in white- and blue-collar workers in a Japanese manufacturing plant.

    PubMed

    Fukushima, Noritoshi; Kitabayashi, Makiko; Kikuchi, Hiroyuki; Sasai, Hiroyuki; Oka, Koichiro; Nakata, Yoshio; Tanaka, Shigeho; Inoue, Shigeru

    2018-05-25

    The times spent in sedentary behavior (SB) and moderate-to-vigorous physical activity (MVPA) are independently associated with health outcomes; however, objective data on physical activity levels including SB among different occupations is limited. We compared accelerometer-measured times spent in SB, light-intensity physical activity (LPA), and MVPA, and the patterns associated with prolonged bouts of SB between white- and blue-collar workers. The study population consisted of 102 full-time plant workers (54 white-collar and 48 blue-collar) who wore a triaxial accelerometer during waking hours for 5 working days. Accelerometer-measured activity levels were categorized as SB (≤1.5 metabolic equivalents (METs)), LPA (1.6-2.9 METs), and MVPA (≥3.0 METs). A sedentary bout was defined as consecutive minutes during which the accelerometer registered less than ≤1.5 METs. Accelerometer variables were compared between white- and blue-collar workers through analysis of covariance. During working hours, white-collar workers spent significantly more time in SB and less time in LPA than blue-collar workers (SB: 6.4 h vs. 4.8 h, 73% vs. 55% of total work time; LPA: 1.9 h vs. 3.5 h, 22% vs. 40% of total work time, p<.001), whereas the MVPA time was similar between the groups. White-collar workers spent significantly more SB time in prolonged sedentary bouts (≥30 min) compared to blue-collar workers. During leisure time, the SB, LPA, and MVPA times were similar between the groups. White-collar workers have significantly longer SB times than blue-collar workers during work hours, and do not compensate for their excess SB during work by reducing SB during leisure time.

  9. Event models and the fan effect.

    PubMed

    Radvansky, G A; O'Rear, Andrea E; Fisher, Jerry S

    2017-08-01

    The current study explored the persistence of event model organizations and how this influences the experience of interference during retrieval. People in this study memorized lists of sentences about objects in locations, such as "The potted palm is in the hotel." Previous work has shown that such information can either be stored in separate event models, thereby producing retrieval interference, or integrated into common event models, thereby eliminating retrieval interference. Unlike prior studies, the current work explored the impact of forgetting up to 2 weeks later on this pattern of performance. We explored three possible outcomes across the various retention intervals. First, consistent with research showing that longer delays reduce proactive and retroactive interference, any retrieval interference effects of competing event models could be reduced over time. Second, the binding of information into events models may weaken over time, causing interference effects to emerge when they had previously been absent. Third, and finally, the organization of information into event models could remain stable over long periods of time. The results reported here are most consistent with the last outcome. While there were some minor variations across the various retention intervals, the basic pattern of event model organization remained preserved over the two-week retention period.

  10. Work, family and daily mobility: a new approach to the problem through a mobility survey.

    PubMed

    Olabarria, Marta; Pérez, Katherine; Santamariña-Rubio, Elena; Aragay, Josep Maria; Capdet, Mayte; Peiró, Rosana; Rodríguez-Sanz, Maica; Artazcoz, Lucía; Borrell, Carme

    2013-01-01

    To analyze gender inequalities in socioeconomic factors affecting the amount of time spent travelling for work-related and home-related reasons among working individuals aged between 30 and 44 years old during a weekday in Catalonia (Spain). A cross-sectional study was conducted. Data were obtained from employed individuals aged between 30 and 44 years of age who reported travelling on the day prior to the interview in the Catalan Mobility Survey 2006 (N = 23,424). Multivariate logistic regression models were adjusted to determine the factors associated with longer time spent travelling according to the reason for travelling (work- or home-related journeys). Odds ratios and 95% confidence intervals are presented. A higher proportion of men travelled and spent more time travelling for work-related reasons, while a higher proportion of women travelled and spend more time travelling for home-related reasons. A higher educational level was associated with greater time spent travelling for work-related reasons in both men and women but was related to an increase in travelling time for home-related reasons only in men. In women, a larger household was associated with greater travel time for home-related reasons and with less travel time for work-related reasons. This study confirms the different mobility patterns in men and women, related to their distinct positions in the occupational, family and domestic spheres. Gender inequalities in mobility within the working population are largely determined by the greater responsibility of women in the domestic and family sphere. This finding should be taken into account in the design of future transport policies. Copyright © 2012 SESPAS. Published by Elsevier Espana. All rights reserved.

  11. Optical Computing 88. Book of Summaries. August 29 - September 2, 1988.

    DTIC Science & Technology

    1988-09-02

    useveravlabW le.faomputpaeconsiof alineaavalaachpidode array driving anOff c1iP etsuaialdreetiama shift regste. 7M two suell.chamasl acoso *optc devices...LSI), automated systems have been demanded for the inspection of patterned wafers to replace the time-consuming and pains taking labor work. The

  12. Innovations in Site Characterization Case Study: The Role of a Conceptual Site Model for Expedited Site Characterization Using the Triad Approach at the Poudre River Site, Fort Collins, Colorado

    EPA Pesticide Factsheets

    This case study examines how systematic planning, an evolving conceptual site model (CSM), dynamic work strategies, and real time measurement technologies can be used to unravel complex contaminant distribution patterns...

  13. Managerial Attention Patterns: A Micro-Behavioral Analysis.

    ERIC Educational Resources Information Center

    Sproull, Lee S.

    This paper describes a study of managerial behavior in educational organizations that focused on managerial attention as an organizational coupling mechanism. Structured observation was used to collect minute-by-minute time allocation protocols for five first-line education program managers over 20 working days, and these protocols were analyzed…

  14. Developmental regulation of DNA replication timing at the human beta globin locus.

    PubMed

    Simon, I; Tenzen, T; Mostoslavsky, R; Fibach, E; Lande, L; Milot, E; Gribnau, J; Grosveld, F; Fraser, P; Cedar, H

    2001-11-01

    The human beta globin locus replicates late in most cell types, but becomes early replicating in erythroid cells. Using FISH to map DNA replication timing around the endogenous beta globin locus and by applying a genetic approach in transgenic mice, we have demonstrated that both the late and early replication states are controlled by regulatory elements within the locus control region. These results also show that the pattern of replication timing is set up by mechanisms that work independently of gene transcription.

  15. Spatial and polarization entanglement of lasing patterns and related dynamic behaviors in laser-diode-pumped solid-state lasers.

    PubMed

    Otsuka, K; Chu, S-C; Lin, C-C; Tokunaga, K; Ohtomo, T

    2009-11-23

    To provide the underlying physical mechanism for formations of spatial- and polarization-entangled lasing patterns (namely, SPEPs), we performed experiments using a c-cut Nd:GdVO(4) microchip laser with off-axis laser-diode pumping. This extends recent work on entangled lasing pattern generation from an isotropic laser, where such a pattern was explained only in terms of generalized coherent states (GCSs) formed by mathematical manipulation. Here, we show that polarization-resolved transverse patterns can be well explained by the transverse mode-locking of distinct orthogonal linearly polarized Ince-Gauss (IG) mode pairs rather than GCSs. Dynamic properties of SPEPs were experimentally examined in both free-running and modulated conditions to identify long-term correlations of IG mode pairs over time. The complete chaos synchronization among IG mode pairs subjected to external perturbation is also demonstrated.

  16. Justice as a dynamic construct: effects of individual trajectories on distal work outcomes.

    PubMed

    Hausknecht, John P; Sturman, Michael C; Roberson, Quinetta M

    2011-07-01

    Despite an amassing organizational justice literature, few studies have directly addressed the temporal patterning of justice judgments and the effects that changes in these perceptions have on important work outcomes. Drawing from Gestalt characteristics theory (Ariely & Carmon, 2000, 2003), we examine the concept of justice trajectories (i.e., levels and trends of individual fairness perceptions over time) and offer empirical evidence to highlight the value of considering fairness within a dynamic context. Participants included 523 working adults who completed surveys about their work experiences on 4 occasions over the course of 1 year. Results indicate that justice trends explained additional variance in distal work outcomes (job satisfaction, organizational commitment, and turnover intentions) after controlling for end-state levels of justice, demonstrating the cumulative effects of justice over time. Findings also reveal that change in procedural justice perceptions affected distal work outcomes more strongly than any other justice dimension. Implications for theory and future investigations of justice as a dynamic construct are discussed.

  17. [Health impact assessment of "white-collar exemption" in Japan].

    PubMed

    Fujino, Yoshihisa; Matsuda, Shinya

    2007-03-01

    This work conducted a health impact assessment (HIA) of the Japanese Government's proposal concerning the introduction of so called "white-collar exemption" into the Japanese labor market. We adopted the Merseyside model and performed a rapid health impact assessment to assess the potential health effects of white-collar exemption. In this HIA, several health determinants which may possibly be affected, both positively and negatively, were identified based on experts' judgments. Literature evidence was assessed using PubMed and other databases. In addition, we searched for the opinions of those affected by white-collar exemption from internet web sites, and six concerns were identified. Long working hours were identified as the most serious concern by both experts and those affected. White-collar exemption may increase irregular working patterns which may be related to sleep disorder, stress, and cardiovascular disease. Family function and social participation will also be affected by irregular working patterns. On the other hand, in terms of stress, white-collar exemption may benefit from a higher degree of job control. There are possibilities that white-collar exemption may enable an improved work-life balance and enable access of some groups of the population, such as people with disabilities or parents looking after children, greater access to the labour market. However, it is uncertain whether the benefits of white-collar exemption would overcome those of the current free-time or flex-time systems. The present work provides a wide range of health impacts of white-collar exemption, and will hopefully attract the attentions of decision-makers and those likely to be affected in order to contribute to policy-making.

  18. Sand moulds milling for one-of-a-kind pieces

    NASA Astrophysics Data System (ADS)

    Rodríguez, A.; Calleja, A.; Olvera, D.; Peñafiel, F. J.; López de Lacalle, L. N.

    2012-04-01

    Time to market is a critical measurement for today's foundry market. Combining 3D digitizing and sand blocks milling is possible to reduce this time. Avoiding the use of a wood pattern, this technique is useful for art pieces or unique parts, when only one component is necessary. The key of the proposed methodology is to achieve enough tool life with conventional tool qualities, avoiding the risk of sand destruction or damage. A special study of tool wear is presented in this work, studying different tool materials and different sand types. Two examples of unique parts are also presented in this work following the proposed methodology in order to reduce time and cost for the rapid reproduction of very short batches.

  19. Busman’s stomach and the embodiment of modernity

    PubMed Central

    Hayward, Rhodri

    2017-01-01

    Abstract This paper examines the relationship between the gastric illness, ‘busman’s stomach’ and the Coronation bus strike of May 1937 in which 27,000 London busworkers walked out for better working conditions and a seven-and-half-hour day. It explores the way in which new patterns of somatisation, gastroenterological techniques, psychological theories and competing understandings of time worked together to create new political institutions and new forms of political action in inter-war Britain. PMID:28216996

  20. Positional error and time-activity patterns in near-highway proximity studies: an exposure misclassification analysis

    PubMed Central

    2013-01-01

    Background The growing interest in research on the health effects of near-highway air pollutants requires an assessment of potential sources of error in exposure assignment techniques that rely on residential proximity to roadways. Methods We compared the amount of positional error in the geocoding process for three different data sources (parcels, TIGER and StreetMap USA) to a “gold standard” residential geocoding process that used ortho-photos, large multi-building parcel layouts or large multi-unit building floor plans. The potential effect of positional error for each geocoding method was assessed as part of a proximity to highway epidemiological study in the Boston area, using all participants with complete address information (N = 703). Hourly time-activity data for the most recent workday/weekday and non-workday/weekend were collected to examine time spent in five different micro-environments (inside of home, outside of home, school/work, travel on highway, and other). Analysis included examination of whether time-activity patterns were differentially distributed either by proximity to highway or across demographic groups. Results Median positional error was significantly higher in street network geocoding (StreetMap USA = 23 m; TIGER = 22 m) than parcel geocoding (8 m). When restricted to multi-building parcels and large multi-unit building parcels, all three geocoding methods had substantial positional error (parcels = 24 m; StreetMap USA = 28 m; TIGER = 37 m). Street network geocoding also differentially introduced greater amounts of positional error in the proximity to highway study in the 0–50 m proximity category. Time spent inside home on workdays/weekdays differed significantly by demographic variables (age, employment status, educational attainment, income and race). Time-activity patterns were also significantly different when stratified by proximity to highway, with those participants residing in the 0–50 m proximity category reporting significantly more time in the school/work micro-environment on workdays/weekdays than all other distance groups. Conclusions These findings indicate the potential for both differential and non-differential exposure misclassification due to geocoding error and time-activity patterns in studies of highway proximity. We also propose a multi-stage manual correction process to minimize positional error. Additional research is needed in other populations and geographic settings. PMID:24010639

  1. Positional error and time-activity patterns in near-highway proximity studies: an exposure misclassification analysis.

    PubMed

    Lane, Kevin J; Kangsen Scammell, Madeleine; Levy, Jonathan I; Fuller, Christina H; Parambi, Ron; Zamore, Wig; Mwamburi, Mkaya; Brugge, Doug

    2013-09-08

    The growing interest in research on the health effects of near-highway air pollutants requires an assessment of potential sources of error in exposure assignment techniques that rely on residential proximity to roadways. We compared the amount of positional error in the geocoding process for three different data sources (parcels, TIGER and StreetMap USA) to a "gold standard" residential geocoding process that used ortho-photos, large multi-building parcel layouts or large multi-unit building floor plans. The potential effect of positional error for each geocoding method was assessed as part of a proximity to highway epidemiological study in the Boston area, using all participants with complete address information (N = 703). Hourly time-activity data for the most recent workday/weekday and non-workday/weekend were collected to examine time spent in five different micro-environments (inside of home, outside of home, school/work, travel on highway, and other). Analysis included examination of whether time-activity patterns were differentially distributed either by proximity to highway or across demographic groups. Median positional error was significantly higher in street network geocoding (StreetMap USA = 23 m; TIGER = 22 m) than parcel geocoding (8 m). When restricted to multi-building parcels and large multi-unit building parcels, all three geocoding methods had substantial positional error (parcels = 24 m; StreetMap USA = 28 m; TIGER = 37 m). Street network geocoding also differentially introduced greater amounts of positional error in the proximity to highway study in the 0-50 m proximity category. Time spent inside home on workdays/weekdays differed significantly by demographic variables (age, employment status, educational attainment, income and race). Time-activity patterns were also significantly different when stratified by proximity to highway, with those participants residing in the 0-50 m proximity category reporting significantly more time in the school/work micro-environment on workdays/weekdays than all other distance groups. These findings indicate the potential for both differential and non-differential exposure misclassification due to geocoding error and time-activity patterns in studies of highway proximity. We also propose a multi-stage manual correction process to minimize positional error. Additional research is needed in other populations and geographic settings.

  2. Patterned titania nanostructures produced by electrochemical anodization of titanium sheet

    NASA Astrophysics Data System (ADS)

    Dong, Junzhe; Ariyanti, Dessy; Gao, Wei; Niu, Zhenjiang; Weil, Emeline

    2017-07-01

    A two-step anodization method has been used to produce patterned arrays of TiO2 on the surface of Ti sheet. Hexagonal ripples were created on Ti substrate after removing the TiO2 layer produced by first-step anodization. The shallow concaves were served as an ideal position for the subsequent step anodization due to their low electrical resistance, resulting in novel hierarchical nanostructures with small pits inside the original ripples. The mechanism of morphology evolution during patterned anodization was studied through changing the anodizing voltages and duration time. This work provides a new idea for controlling nanostructures and thus tailoring the photocatalytic property and wettability of anodic TiO2.

  3. Impact of a workplace 'sit less, move more' program on efficiency-related outcomes of office employees.

    PubMed

    Puig-Ribera, Anna; Bort-Roig, Judit; Giné-Garriga, Maria; González-Suárez, Angel M; Martínez-Lemos, Iván; Fortuño, Jesús; Martori, Joan C; Muñoz-Ortiz, Laura; Milà, Raimon; Gilson, Nicholas D; McKenna, Jim

    2017-05-16

    Few studies have examined the impact of 'sit less, move more' interventions on workplace performance. This study assessed the short and mid-term impacts of and patterns of change within, a 19-week workplace web-based intervention (Walk@WorkSpain; W@WS; 2010-11) on employees´ presenteeism, mental well-being and lost work performance. A site randomised control trial recruited employees at six Spanish university campuses (n = 264; 42 ± 10 years; 171 female), assigned by worksite and campus to an Intervention (IG; used W@WS; n = 129; 87 female) or an active Comparison group (A-CG; pedometer, paper diary and self-reported sitting time; n = 135; 84 female). A linear mixed model assessed changes between the baseline, ramping (8 weeks), maintenance (11 weeks) and follow-up (two months) phases for the IG versus A-CG on (i) % of lost work productivity (Work Limitations Questionnaire; WLQ); (ii) three scales for presenteeism (WLQ) assessing difficulty meeting scheduling demands (Time), performing cognitive and inter-personal tasks (Mental-Interpersonal) and decrements in meeting the quantity, quality and timeliness of completed work (Output); and (iii) mental well-being (Warwick-Edinburgh Mental Well-being Scale). T-tests assessed differences between groups for changes on the main outcomes. In the IG, a multivariate logistic regression model identified patterns of response according to baseline socio-demographic variables, physical activity and sitting time. There was a significant 2 (group) × 2 (program time points) interaction for the Time (F [3]=8.69, p = 0.005), Mental-Interpersonal (F [3]=10.01, p = 0.0185), Output scales for presenteeism (F [3]=8.56, p = 0.0357), and for % of lost work performance (F [3]=10.31, p = 0.0161). Presenteeism and lost performance rose significantly in both groups across all study time points; after baseline performance was consistently better in the IG than in the A-CG. Better performance was linked to employees being more active (Time, p = 0.041) and younger (Mental-interpersonal, p = 0.057; Output, p = 0.017). Higher total sitting time during nonworking days (Mental-interpersonal, p = 0.019) and lower sitting time during workdays (WLQ Index, p = 0.013) also improved performance. Versus an active comparison condition, a 'sit less, move more` workplace intervention effectively reduced an array of markers of lost workday productivity. NCT02960750 ; Date of registration: 07/11/2016.

  4. Reorientation Timescales and Pattern Dynamics for Titan's Dunes: Does the Tail Wag the Dog or the Dragon?

    NASA Astrophysics Data System (ADS)

    Hayes, A. G.; Ewing, R. C.; Cassini Radar Science Team, T.

    2011-12-01

    Fields of bedform patterns persist across many orders of magnitude, from cm-scale sub-aqueous current ripples to km-scale aeolian dunes, and form with surprisingly little difference in expression despite a range of formative environments. Because of the remarkable similarity between and among patterns, extracting information about climate and environment from these patterns is a challenge. For example, crest orientation is not diagnostic of a particular flow regime; similar patterns form under many different flow configurations. On Titan, these challenges have played out with many attempts to reconcile dune-field patterns with modeled and expected wind regimes. We propose that thinking about the change in dune orientation, rather than the orientation itself, can provide new insights on the long-term stability of the dune-field patterns and the formative wind regime. In this work, we apply the re-orientation model presented by Werner and Kocurek [Geology, 1997] to the equatorial dune fields of Titan. We measure variations in pattern parameters (crest spacing, crest length and defect density, which is the number of defect pairs per total crest length) both within and between Titan's dune fields to describe pattern maturity and identify areas where changes in dune orientation are likely to occur (or may already be occurring). Measured defect densities are similar to Earth's largest linear dune fields, such as the Namib Sand Sea and the Simpson Desert. We use measured defect densities in the Werner and Kocurek model to estimate crestline reorientation rates. We find reorientation timescales varying from ten to a hundred thousand times the average migration timescale (time to migrate a bedform one meter, ~1 Titan year according to Tokano (Aeolian Research, 2010)). Well organized patterns have the longest reorientation time scales (~10^5 migration timescales), while the topographically or spatially isolated patches of dunes show the shortest reorientation times (~10^3 migration timescales). In addition, comparisons between spacing and defect density of Titan's dunes and some of the largest fields observed on Earth and Mars reveal that dune patterns on all three planets are geometrically similar, suggesting that growth and organization share common pattern dynamics. Our results suggest that Titan's dunes may react to gross bedform transport averaged over orbital timescales, relaxing the requirement that a single modern wind regime is required to produce the observed pattern.

  5. Increasing Spontaneous Retinal Activity before Eye Opening Accelerates the Development of Geniculate Receptive Fields

    PubMed Central

    Davis, Zachary W.; Chapman, Barbara

    2015-01-01

    Visually evoked activity is necessary for the normal development of the visual system. However, little is known about the capacity for patterned spontaneous activity to drive the maturation of receptive fields before visual experience. Retinal waves provide instructive retinotopic information for the anatomical organization of the visual thalamus. To determine whether retinal waves also drive the maturation of functional responses, we increased the frequency of retinal waves pharmacologically in the ferret (Mustela putorius furo) during a period of retinogeniculate development before eye opening. The development of geniculate receptive fields after receiving these increased neural activities was measured using single-unit electrophysiology. We found that increased retinal waves accelerate the developmental reduction of geniculate receptive field sizes. This reduction is due to a decrease in receptive field center size rather than an increase in inhibitory surround strength. This work reveals an instructive role for patterned spontaneous activity in guiding the functional development of neural circuits. SIGNIFICANCE STATEMENT Patterned spontaneous neural activity that occurs during development is known to be necessary for the proper formation of neural circuits. However, it is unknown whether the spontaneous activity alone is sufficient to drive the maturation of the functional properties of neurons. Our work demonstrates for the first time an acceleration in the maturation of neural function as a consequence of driving patterned spontaneous activity during development. This work has implications for our understanding of how neural circuits can be modified actively to improve function prematurely or to recover from injury with guided interventions of patterned neural activity. PMID:26511250

  6. Neuromorphic Hardware Architecture Using the Neural Engineering Framework for Pattern Recognition.

    PubMed

    Wang, Runchun; Thakur, Chetan Singh; Cohen, Gregory; Hamilton, Tara Julia; Tapson, Jonathan; van Schaik, Andre

    2017-06-01

    We present a hardware architecture that uses the neural engineering framework (NEF) to implement large-scale neural networks on field programmable gate arrays (FPGAs) for performing massively parallel real-time pattern recognition. NEF is a framework that is capable of synthesising large-scale cognitive systems from subnetworks and we have previously presented an FPGA implementation of the NEF that successfully performs nonlinear mathematical computations. That work was developed based on a compact digital neural core, which consists of 64 neurons that are instantiated by a single physical neuron using a time-multiplexing approach. We have now scaled this approach up to build a pattern recognition system by combining identical neural cores together. As a proof of concept, we have developed a handwritten digit recognition system using the MNIST database and achieved a recognition rate of 96.55%. The system is implemented on a state-of-the-art FPGA and can process 5.12 million digits per second. The architecture and hardware optimisations presented offer high-speed and resource-efficient means for performing high-speed, neuromorphic, and massively parallel pattern recognition and classification tasks.

  7. A Smartphone App Reveals Erratic Diurnal Eating Patterns in Humans that Can Be Modulated for Health Benefits.

    PubMed

    Gill, Shubhroz; Panda, Satchidananda

    2015-11-03

    A diurnal rhythm of eating-fasting promotes health, but the eating pattern of humans is rarely assessed. Using a mobile app, we monitored ingestion events in healthy adults with no shift-work for several days. Most subjects ate frequently and erratically throughout wakeful hours, and overnight fasting duration paralleled time in bed. There was a bias toward eating late, with an estimated <25% of calories being consumed before noon and >35% after 6 p.m. "Metabolic jetlag" resulting from weekday/weekend variation in eating pattern akin to travel across time zones was prevalent. The daily intake duration (95% interval) exceeded 14.75 hr for half of the cohort. When overweight individuals with >14 hr eating duration ate for only 10-11 hr daily for 16 weeks assisted by a data visualization (raster plot of dietary intake pattern, "feedogram") that we developed, they reduced body weight, reported being energetic, and improved sleep. Benefits persisted for a year. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Microwave-assisted extraction of polycyclic aromatic compounds from coal.

    PubMed

    Kerst, M; Andersson, J T

    2001-08-01

    Microwave-assisted extraction (MAE) of polycyclic aromatic compounds (PACs) from coal is shown to give the same pattern of compounds as Soxhlet extraction. MAE requires only 10 mL solvent and 10 min extraction time whereas Soxhlet uses 200 mL and takes 24 h. Although the yields were lower, dichloromethane (DCM) was preferred to pyridine, N-methyl-2-pyrrolidone (NMP), and NMP with CS2 because the pattern of the PACs is shown to be independent of solvent and DCM is a much more convenient solvent to work with.

  9. Job satisfaction among Australian doctors: the use of latent class analysis.

    PubMed

    Joyce, Catherine; Wang, Wei Chun

    2015-10-01

    To identify patterns of job satisfaction among Australian doctors using latent class analysis, and to determine the relationships of these patterns to personal and professional characteristics so as to improve satisfaction and minimize medical wastage. MABEL (Medicine in Australia: Balancing Employment and Life) data in 2011 were used. The study collected information on 5764 doctors about their job satisfaction, demographic characteristics, their health, country of medical training, opportunities for professional development and social interaction, taking time off work, views of patients' expectations, unpredictable working hours, hours worked per week, preference to reduce hours and intention to leave the medical workforce. Four latent classes of job satisfaction were identified: 5.8% had high job satisfaction; 19.4% had low satisfaction with working hours; 16.1% had high satisfaction with working hours but felt undervalued; and 6.5% had low job satisfaction. Low job satisfaction was associated with reporting poor health, having trained outside Australia, having poor opportunities for professional development and working longer hours. Low satisfaction was associated with a preference to reduce work hours and an intention to leave the medical workforce. To improve job satisfaction and minimize medical wastage, policies need to address needs of overseas trained doctors, provide continuing professional development and provide good health care for doctors. © The Author(s) 2015.

  10. Developing professional status: an investigation into the working patterns, working relationships and vision for the future of UK clinical dental technicians.

    PubMed

    Leyssen, W; Clark, R K F; Gallagher, J E; Radford, D R

    2013-01-01

    To investigate the working patterns and patient base of registered clinical dental technicians (CDTs); their relationships with dentists and other professionals in the dental team; their willingness to work within the NHS and their expectations for the future as a new professional group. Face-to-face qualitative interviews of registered CDTs, selected because of their geographic representation and mode of working, informed the development of a postal questionnaire survey of all early registrants with the General Dental Council (GDC). The majority of CDTs reported working part-time, often combining clinical practice with their role as a dental technician. They reported both positive and negative working relationships with dentists and dental technicians, demonstrating collaboration and/or competition depending on whether the scope of CDTs was respected and patient care was shared or lost. CDTs role in the NHS was limited because they did not have the status of becoming a recognised provider of dental care. There was a desire to expand their scope of practice in future. CDTs are embracing their new status as an occupational group within dentistry. Core features of becoming a professional group were exhibited including the importance of social and financial status and the need to negotiate their current and future roles in the healthcare system.

  11. Bayesian Ising approximation for learning dictionaries of multispike timing patterns in premotor neurons

    NASA Astrophysics Data System (ADS)

    Hernandez Lahme, Damian; Sober, Samuel; Nemenman, Ilya

    Important questions in computational neuroscience are whether, how much, and how information is encoded in the precise timing of neural action potentials. We recently demonstrated that, in the premotor cortex during vocal control in songbirds, spike timing is far more informative about upcoming behavior than is spike rate (Tang et al, 2014). However, identification of complete dictionaries that relate spike timing patterns with the controled behavior remains an elusive problem. Here we present a computational approach to deciphering such codes for individual neurons in the songbird premotor area RA, an analog of mammalian primary motor cortex. Specifically, we analyze which multispike patterns of neural activity predict features of the upcoming vocalization, and hence are important codewords. We use a recently introduced Bayesian Ising Approximation, which properly accounts for the fact that many codewords overlap and hence are not independent. Our results show which complex, temporally precise multispike combinations are used by individual neurons to control acoustic features of the produced song, and that these code words are different across individual neurons and across different acoustic features. This work was supported, in part, by JSMF Grant 220020321, NSF Grant 1208126, NIH Grant NS084844 and NIH Grant 1 R01 EB022872.

  12. The impact of shift patterns on junior doctors' perceptions of fatigue, training, work/life balance and the role of social support

    PubMed Central

    Brown, M; Rapport, F; Hutchings, H; Dahlgren, A; Davies, G; Ebden, P

    2010-01-01

    Background The organisation of junior doctors' work hours has been radically altered following the partial implementation of the European Working Time Directive. Poorly designed shift schedules cause excessive disruption to shift workers' circadian rhythms. Method Interviews and focus groups were used to explore perceptions among junior doctors and hospital managers regarding the impact of the European Working Time Directive on patient care and doctors' well-being. Results Four main themes were identified. Under “Doctors shift rotas”, doctors deliberated the merits and demerits of working seven nights in row. They also discussed the impact on fatigue of long sequences of day shifts. “Education and training” focused on concerns about reduced on-the-job learning opportunities under the new working time arrangements and also about the difficulties of finding time and energy to study. “Work/life balance” reflected the conflict between the positive aspects of working on-call or at night and the impact on life outside work. “Social support structures” focused on the role of morale and team spirit. Good support structures in the work place counteracted and compensated for the effects of negative role stressors, and arduous and unsocial work schedules. Conclusions The impact of junior doctors' work schedules is influenced by the nature of specific shift sequences, educational considerations, issues of work/life balance and by social support systems. Poorly designed shift rotas can have negative impacts on junior doctors' professional performance and educational training, with implications for clinical practice, patient care and the welfare of junior doctors. PMID:21127102

  13. The impact of shift patterns on junior doctors' perceptions of fatigue, training, work/life balance and the role of social support.

    PubMed

    Brown, M; Tucker, P; Rapport, F; Hutchings, H; Dahlgren, A; Davies, G; Ebden, P

    2010-12-01

    The organisation of junior doctors' work hours has been radically altered following the partial implementation of the European Working Time Directive. Poorly designed shift schedules cause excessive disruption to shift workers' circadian rhythms. Interviews and focus groups were used to explore perceptions among junior doctors and hospital managers regarding the impact of the European Working Time Directive on patient care and doctors' well-being. Four main themes were identified. Under "Doctors shift rotas", doctors deliberated the merits and demerits of working seven nights in row. They also discussed the impact on fatigue of long sequences of day shifts. "Education and training" focused on concerns about reduced on-the-job learning opportunities under the new working time arrangements and also about the difficulties of finding time and energy to study. "Work/life balance" reflected the conflict between the positive aspects of working on-call or at night and the impact on life outside work. "Social support structures" focused on the role of morale and team spirit. Good support structures in the work place counteracted and compensated for the effects of negative role stressors, and arduous and unsocial work schedules. The impact of junior doctors' work schedules is influenced by the nature of specific shift sequences, educational considerations, issues of work/life balance and by social support systems. Poorly designed shift rotas can have negative impacts on junior doctors' professional performance and educational training, with implications for clinical practice, patient care and the welfare of junior doctors.

  14. Utilizing Electronic Medical Records to Discover Changing Trends of Medical Behaviors Over Time*

    PubMed Central

    Yin, Liangying; Dong, Wei; He, Chunhua; Duan, Huilong

    2017-01-01

    Summary Objectives Medical behaviors are playing significant roles in the delivery of high quality and cost-effective health services. Timely discovery of changing frequencies of medical behaviors is beneficial for the improvement of health services. The main objective of this work is to discover the changing trends of medical behaviors over time. Methods This study proposes a two-steps approach to detect essential changing patterns of medical behaviors from Electronic Medical Records (EMRs). In detail, a probabilistic topic model, i.e., Latent Dirichlet allocation (LDA), is firstly applied to disclose yearly treatment patterns in regard to the risk stratification of patients from a large volume of EMRs. After that, the changing trends by comparing essential/critical medical behaviors in a specific time period are detected and analyzed, including changes of significant patient features with their values, and changes of critical treatment interventions with their occurring time stamps. Results We verify the effectiveness of the proposed approach on a clinical dataset containing 12,152 patient cases with a time range of 10 years. Totally, 135 patients features and 234 treatment interventions in three treatment patterns were selected to detect their changing trends. In particular, evolving trends of yearly occurring probabilities of the selected medical behaviors were categorized into six content changing patterns (i.e, 112 growing, 123 declining, 43 up-down, 16 down-up, 35 steady, and 40 jumping), using the proposed approach. Besides, changing trends of execution time of treatment interventions were classified into three occurring time changing patterns (i.e., 175 early-implemented, 50 steady-implemented and 9 delay-implemented). Conclusions Experimental results show that our approach has an ability to utilize EMRs to discover essential evolving trends of medical behaviors, and thus provide significant potential to be further explored for health services redesign and improvement. PMID:28474729

  15. Understanding human dynamics in microblog posting activities

    NASA Astrophysics Data System (ADS)

    Jiang, Zhihong; Zhang, Yubao; Wang, Hui; Li, Pei

    2013-02-01

    Human activity patterns are an important issue in behavior dynamics research. Empirical evidence indicates that human activity patterns can be characterized by a heavy-tailed inter-event time distribution. However, most researchers give an understanding by only modeling the power-law feature of the inter-event time distribution, and those overlooked non-power-law features are likely to be nontrivial. In this work, we propose a behavior dynamics model, called the finite memory model, in which humans adaptively change their activity rates based on a finite memory of recent activities, which is driven by inherent individual interest. Theoretical analysis shows a finite memory model can properly explain various heavy-tailed inter-event time distributions, including a regular power law and some non-power-law deviations. To validate the model, we carry out an empirical study based on microblogging activity from thousands of microbloggers in the Celebrity Hall of the Sina microblog. The results show further that the model is reasonably effective. We conclude that finite memory is an effective dynamics element to describe the heavy-tailed human activity pattern.

  16. Conceptual recurrence plots: revealing patterns in human discourse.

    PubMed

    Angus, Daniel; Smith, Andrew; Wiles, Janet

    2012-06-01

    Human discourse contains a rich mixture of conceptual information. Visualization of the global and local patterns within this data stream is a complex and challenging problem. Recurrence plots are an information visualization technique that can reveal trends and features in complex time series data. The recurrence plot technique works by measuring the similarity of points in a time series to all other points in the same time series and plotting the results in two dimensions. Previous studies have applied recurrence plotting techniques to textual data; however, these approaches plot recurrence using term-based similarity rather than conceptual similarity of the text. We introduce conceptual recurrence plots, which use a model of language to measure similarity between pairs of text utterances, and the similarity of all utterances is measured and displayed. In this paper, we explore how the descriptive power of the recurrence plotting technique can be used to discover patterns of interaction across a series of conversation transcripts. The results suggest that the conceptual recurrence plotting technique is a useful tool for exploring the structure of human discourse.

  17. Cognition-emotion interactions: patterns of change and implications for math problem solving

    PubMed Central

    Trezise, Kelly; Reeve, Robert A.

    2014-01-01

    Surprisingly little is known about whether relationships between cognitive and emotional states remain stable or change over time, or how different patterns of stability and/or change in the relationships affect problem solving abilities. Nevertheless, cross-sectional studies show that anxiety/worry may reduce working memory (WM) resources, and the ability to minimize the effects anxiety/worry is higher in individuals with greater WM capacity. To investigate the patterns of stability and/or change in cognition-emotion relations over time and their implications for problem solving, 126 14-year-olds’ algebraic WM and worry levels were assessed twice in a single day before completing an algebraic math problem solving test. We used latent transition analysis to identify stability/change in cognition-emotion relations, which yielded a six subgroup solution. Subgroups varied in WM capacity, worry, and stability/change relationships. Among the subgroups, we identified a high WM/low worry subgroup that remained stable over time and a high WM/high worry, and a moderate WM/low worry subgroup that changed to low WM subgroups over time. Patterns of stability/change in subgroup membership predicted algebraic test results. The stable high WM/low worry subgroup performed best and the low WM capacity-high worry “unstable across time” subgroup performed worst. The findings highlight the importance of assessing variations in cognition-emotion relationships over time (rather than assessing cognition or emotion states alone) to account for differences in problem solving abilities. PMID:25132830

  18. Dynamics of Conflicts in Wikipedia

    PubMed Central

    Yasseri, Taha; Sumi, Robert; Rung, András; Kornai, András; Kertész, János

    2012-01-01

    In this work we study the dynamical features of editorial wars in Wikipedia (WP). Based on our previously established algorithm, we build up samples of controversial and peaceful articles and analyze the temporal characteristics of the activity in these samples. On short time scales, we show that there is a clear correspondence between conflict and burstiness of activity patterns, and that memory effects play an important role in controversies. On long time scales, we identify three distinct developmental patterns for the overall behavior of the articles. We are able to distinguish cases eventually leading to consensus from those cases where a compromise is far from achievable. Finally, we analyze discussion networks and conclude that edit wars are mainly fought by few editors only. PMID:22745683

  19. Physician job satisfaction as a public health issue.

    PubMed

    Kravitz, Richard L

    2012-12-14

    In Hirschman's classic formulation, physicians can signal discontent with their conditions of work by "exiting" (leaving the profession or not entering it in the first place) or by giving "voice" to their concerns (e.g. complaining, protesting, bargaining collectively, or conducting work actions and strikes). This Commentary reviews the findings of a survey of Israeli neonatologists by Moshe et al. Survey respondents were satisfied with their careers but not with salary, patient care demands, and leisure time, a pattern that has been seen in other countries, particularly within "small, acute care specialties" (SACS). One question for policymakers is how to help physicians in SACS maintain work-life balance and avoid burnout while providing superb patient care. The Commentary considers several possible solutions while advocating for rigorous and comprehensive monitoring of physician satisfaction over time.

  20. Factors contributing to employment patterns after liver transplantation.

    PubMed

    Beal, Eliza W; Tumin, Dmitry; Mumtaz, Khalid; Nau, Michael; Tobias, Joseph D; Hayes, Don; Washburn, Kenneth; Black, Sylvester M

    2017-06-01

    Many liver transplant recipients return to work, but their patterns of employment are unclear. We examine patterns of employment 5 years after liver transplantation. First-time liver transplant recipients ages 18-60 years transplanted from 2002 to 2009 and surviving at least 5 years were identified in the United Network for Organ Sharing registry. Recipients' post-transplant employment status was classified as follows: (i) never employed; (ii) returned to work within 2 years and remained employed (continuous employment); (iii) returned to work within 2 years, but was subsequently unemployed (intermittent employment); or (iv) returned to work ≥3 years post-transplant (delayed employment). Of 28 306 liver recipients identified during the study period, 12 998 survived at least 5 years and contributed at least 1 follow-up of employment status. A minority of patients (4654; 36%) were never employed, while 3780 (29%) were continuously employed, 3027 (23%) were intermittently employed, and 1537 (12%) had delayed employment. In multivariable logistic regression analysis, predictors of intermittent and delayed employment included lower socioeconomic status, higher local unemployment rates, and post-transplant comorbidities or complications. Never, intermittent, and delayed employment are common after liver transplantation. Socioeconomic and labor market characteristics may add to clinical factors that limit liver transplant recipients' continuous employment. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. A novel grey-fuzzy-Markov and pattern recognition model for industrial accident forecasting

    NASA Astrophysics Data System (ADS)

    Edem, Inyeneobong Ekoi; Oke, Sunday Ayoola; Adebiyi, Kazeem Adekunle

    2017-10-01

    Industrial forecasting is a top-echelon research domain, which has over the past several years experienced highly provocative research discussions. The scope of this research domain continues to expand due to the continuous knowledge ignition motivated by scholars in the area. So, more intelligent and intellectual contributions on current research issues in the accident domain will potentially spark more lively academic, value-added discussions that will be of practical significance to members of the safety community. In this communication, a new grey-fuzzy-Markov time series model, developed from nondifferential grey interval analytical framework has been presented for the first time. This instrument forecasts future accident occurrences under time-invariance assumption. The actual contribution made in the article is to recognise accident occurrence patterns and decompose them into grey state principal pattern components. The architectural framework of the developed grey-fuzzy-Markov pattern recognition (GFMAPR) model has four stages: fuzzification, smoothening, defuzzification and whitenisation. The results of application of the developed novel model signify that forecasting could be effectively carried out under uncertain conditions and hence, positions the model as a distinctly superior tool for accident forecasting investigations. The novelty of the work lies in the capability of the model in making highly accurate predictions and forecasts based on the availability of small or incomplete accident data.

  2. Work-related behaviour and experience patterns of physicians compared to other professions.

    PubMed

    Voltmer, Edgar; Kieschke, Ulf; Spahn, Claudia

    2007-08-11

    To identify health risk factors and resources of physicians in comparison with other professions. Data of cross-sectional mail surveys conducted among German physicians (n = 344), teachers (n = 5169), policemen (n = 851), prison officers (n = 3653), and starting entrepreneurs (n = 632) were analysed regarding eleven health-relevant dimensions and four behaviour patterns examined by the questionnaire "Work-Related Behaviour and Experience Pattern (AVEM)". Only 17% of the physicians showed healthy behaviour and experience patterns. With 43%, they scored highest in terms of reduced working motivation. Together with the teachers, they also had the highest scores for resignation and burnout (27%). Satisfaction with life and work as well as social support showed medium scores. Starting entrepreneurs showed the healthiest patterns (45%), but also the highest risk pattern for overexertion (38%). It was possible to identify clear risk patterns for profession-related psychosocial symptoms and impairments. The high scores for reduced working motivation demonstrate the need for interventions to improve organisation of health care and individual coping strategies.

  3. Spatiotemporal patterns of population distribution as crucial element for risk management

    NASA Astrophysics Data System (ADS)

    Gokesch, Karin; Promper, Catrin; van Westen, Cees J.; Glade, Thomas

    2014-05-01

    The spatiotemporal distribution and presence of the population in a certain area is a crucial element within natural hazard risk management, especially in the case of rapid onset hazard events and emergency management. When fast onset hazards such as earthquakes, flash floods or industrial accidents occur, people may not have adequate time for evacuation and the emergency management requires a fast response and reaction. Therefore, information on detailed distribution of people affected by a certain hazard is important for a fast assessment of the situation including the number and the type of people (distinguishing between elderly or handicapped people, children, working population etc.) affected. This study thus aims at analyzing population distribution on an hourly basis for different days e.g. workday or holiday. The applied method combines the basic assessment of population distribution in a given area with specific location-related patterns of distribution-changes over time. The calculations are based on detailed information regarding the expected presence of certain groups of people, e.g. school children, working or elderly people, which all show different patterns of movement over certain time periods. The study area is the city of Waidhofen /Ybbs located in the Alpine foreland in the Southwest of Lower Austria. This city serves as a regional center providing basic infrastructure, shops and schools for the surrounding countryside. Therefore a lot of small and medium businesses are located in this area showing a rather high variation of population present at different times of the day. The available building footprint information was classified with respect to building type and occupancy type, which was used to estimate the expected residents within the buildings, based on the floorspace of the buildings and the average floorspace per person. Additional information on the distribution and the average duration of stay of the people in these buildings was assessed using general population statistics and specific information about selected buildings, such as schools, hospitals or homes for the elderly, to calculate the distribution patterns for each group of people over time.

  4. Inferring the Limit Behavior of Some Elementary Cellular Automata

    NASA Astrophysics Data System (ADS)

    Ruivo, Eurico L. P.; de Oliveira, Pedro P. B.

    Cellular automata locally define dynamical systems, discrete in space, time and in the state variables, capable of displaying arbitrarily complex global emergent behavior. One core question in the study of cellular automata refers to their limit behavior, that is, to the global dynamical features in an infinite time evolution. Previous works have shown that for finite time evolutions, the dynamics of one-dimensional cellular automata can be described by regular languages and, therefore, by finite automata. Such studies have shown the existence of growth patterns in the evolution of such finite automata for some elementary cellular automata rules and also inferred the limit behavior of such rules based upon the growth patterns; however, the results on the limit behavior were obtained manually, by direct inspection of the structures that arise during the time evolution. Here we present the formalization of an automatic method to compute such structures. Based on this, the rules of the elementary cellular automata space were classified according to the existence of a growth pattern in their finite automata. Also, we present a method to infer the limit graph of some elementary cellular automata rules, derived from the analysis of the regular expressions that describe their behavior in finite time. Finally, we analyze some attractors of two rules for which we could not compute the whole limit set.

  5. Seasonal evolution of S q current system at sub-auroral latitude

    NASA Astrophysics Data System (ADS)

    Vichare, Geeta; Rawat, Rahul; Hanchinal, A.; Sinha, A. K.; Dhar, A.; Pathan, B. M.

    2012-11-01

    The quiet-time (Σ K p ≤ 3) daily variations of the geomagnetic field at the Indian Antarctic station, Maitri (Geographic Coord.: 70.75°S, 11.73°E; Geomagnetic Coord.: 66.84°S, 56.29°E) during two consecutive years of a solar minimum are considered in order to investigate the characteristics of the solar quiet ( S q) current system. The present work reports the signatures of the south limb of the S q current loop of the southern hemisphere over a sub-auroral station. It is observed that the seasonal variation of the S q current strength over Maitri is strongest during the summer months and weakest during the winter months. In spite of the total darkness during the winter months, an S q pattern is identified at Maitri. The range of the horizontal field variation in the daily S q pattern during summer is one order higher than that during winter. An interesting feature regarding the phase of the local time variation in the seasonal pattern is found here. A sharp shift in the time of the peak S q current to later local times (> 1 hour per month) is observed during January-February and July-August, which may correspond to the transition from the complete presence, or absence, of sunlight to partial sunlight. The differences in the incoming solar UV radiation during such transitions can cause a sudden change in the local ionospheric conductivity pattern, and can also trigger some unusual thermo-tidal activity, that might be responsible for modifying the global S q pattern.

  6. Family Kinship Patterns and Female Sex Work in the Informal Urban Settlement of Kibera, Nairobi, Kenya.

    PubMed

    Ngugi, Elizabeth N; Benoit, Cecilia; Hallgrimsdottir, Helga; Jansson, Mikael; Roth, Eric A

    2012-06-01

    A basic ecological and epidemiological question is why some women enter into commercial sex work while other women in the same socio-economic environment never do. To address this question respondent driven sampling principles were adopted to recruit and collect data for 161 female sex workers and 159 same aged women who never engaged in commercial sex in Kibera, a large informal settlement in Nairobi, Kenya. Univariate analysis indicated that basic kinship measures, including number of family members seen during adolescence and at present, not having a male guardian while growing up, and earlier times of ending relationships with both male and female guardians were associated with commercial sex work in Kibera. Multivariate analysis via logistic regression modeling showed that not having a male guardian during childhood, low education attainment and a small number of family members seen at adolescence were all significant predictors of entering sex work. By far the most important predictor of entering sex work was not having any male guardian, e.g., father, uncle, older brother, etc. during childhood. Results are interpreted in light of the historic pattern of sub-Saharan African child fostering and their relevance for young women in Kibera today.

  7. Strategies to keep working among workers with common mental disorders - a grounded theory study.

    PubMed

    Danielsson, Louise; Elf, Mikael; Hensing, Gunnel

    2017-11-28

    Most people with common mental disorders (CMDs) are employed and working, but few studies have looked into how they manage their jobs while ill. This study explores workers' experiences of strategies to keep working while suffering from CMDs. In this grounded theory study, we interviewed 19 women and eight men with depression or anxiety disorders. They were 19-65 years old and had different occupations. Constant comparison method was used in the analysis. We identified a core pattern in the depressed and anxious workers' attempts to sustain their capacities, defined as Managing work space. The core pattern comprised four categories describing different cognitive, behavioral, and social strategies. The categories relate to a process of sustainability. Two categories reflected more reactive and temporary strategies, occurring mainly in the onset phase of illness: Forcing the work role and Warding off work strain. The third category, Recuperating from work, reflected strategies during both onset and recovery phases. The fourth category, Reflexive adaptation, was present mainly in the recovery phase and involved reflective strategies interpreted as more sustainable over time. The results can deepen understanding among rehabilitation professionals about different work-related strategies in depressed and anxious workers. Increased awareness of the meaning and characteristics of strategies can inform a person-oriented approach in rehabilitation. The knowledge can be used in clinical encounters to reflect together with the patient, exploring present options and introducing modifications to their particular work and life context. Implications for rehabilitation Self-managed work functioning in common mental disorders involves diverse strategies. Strategies interpreted as sustainable over time, seem to be reflective in the sense that the worker consciously applies and adapts the strategies. However, at the onset of illness, such reflection is difficult to develop as the worker might not want to realize their reduced functioning. Rehabilitation professionals' awareness of different strategies can facilitate a person-centered approach and understanding of the vocational rehabilitation process.

  8. The Changing Nature and Patterns of Work and Implications for VET. Review of Research.

    ERIC Educational Resources Information Center

    Waterhouse, Peter; Wilson, Bruce; Ewer, Peter

    An overview of recent literature on changes in the nature and patterns of work and their implications for vocational education and training (VET) is offered. Changes in the nature and patterns of work present significant challenges to the VET sector. More women have entered the work force; unemployment has reemerged as a significant factor;…

  9. Multiple bunch HOM evaluation for ERL cavities

    NASA Astrophysics Data System (ADS)

    Xu, Chen; Ben-Zvi, I.; Blaskiewicz, Michael M.; Hao, Yue; Ptitsyn, Vadim

    2017-09-01

    In this work we investigate the effect of the bunch pattern in a linac on the Higher Order Mode (HOM) power generation. The future ERL-based electron-ion collider eRHIC at BNL is used as an illustrative example. This ERL has multiple high current Superconducting Radiofrequency (SRF) 5-cell cavities. The HOM power generated when a single bunch traverses the cavity is estimated by the corresponding loss factor. Multiple re-circulations through the Energy Recovery Linac (ERL) create a specific bunch pattern. In this case the loss factor can be different than the single bunch loss factor. HOM power can vary dramatically when the ERL bunch pattern changes. The HOM power generation can be surveyed in the time and frequency domains. We estimate the average HOM power in a 5-cell cavity with different ERL bunch patterns.

  10. Gender trends in dental practice patterns. A review of current U.S. literature.

    PubMed

    Dolan, T A

    1991-01-01

    This paper reviews three recent reports of national gender trends in dental practice patterns. Although the three independent cross-sectional studies were conducted at different points in time, used different sampling strategies, and used similar but independent survey instruments, findings were consistent across studies. In summary: Women dentists are less likely to be married and have fewer children. Women are more likely to assume child rearing and household responsibilities. Women are less likely to be practice owners. Women worked slightly fewer hours per week and weeks per year, and were more likely to take a leave of absence for illness or child rearing. However, women dentists demonstrate a far greater professional work commitment than was previously reported in the literature. Women earn significantly less income from the practice of dentistry, even after controlling for age, practice ownership, hours worked per week, and other personal characteristics. The most current "Gender Wage Gap" estimates range from 57.7% for specialists to 75.4% for general practitioners (8). delta.

  11. Patterns of paid and unpaid work: the influence of power, social context, and family background.

    PubMed

    McMullin, Julie Ann

    2005-01-01

    Over the last several decades there have been changes in how paid and unpaid labour is divided between men and women: The rate of women's participation in the labour force women has increased as has men's participation in household labour. Although a plethora of research has addressed these changes by analysing couple and individual data, few have examined them within the context of multi-generational families. Using a case study analysis of a three-generation family, this paper shows that gender, class, social context, and family background influence how paid and unpaid work is divided within families. The case study shows that the social context of a given time conditions the options women and men have available to them in negotiating the balance of work and family responsibilities. Yet within this context, family background also matters. Negative childhood experiences were an impetus for adult children negotiating patterns of paid and unpaid labour that were different from those of their parents.

  12. Work overcommitment: Is it a trait or a state?

    PubMed

    du Prel, Jean-Baptist; Runeson-Broberg, Roma; Westerholm, Peter; Alfredsson, Lars; Fahlén, Göran; Knutsson, Anders; Nordin, Maria; Peter, Richard

    2018-01-01

    Effort-reward imbalance (ERI) is a well-tested work-related stress model with three components, the two extrinsic components "efforts" and "rewards" and the one intrinsic component "overcommitment". While an imbalance between "efforts" and "rewards" leads to strain reactions, "work-related overcommitment" (OC) has been described as a personal characteristic with a set of attitudes, behaviours, and emotions reflecting excessive striving combined with a strong desire for approval. However, the question whether OC is a personality trait or a response pattern sensitive to changes in the work context (state) is still open. 2940 Swedish industrial employees were included in this longitudinal analysis of the WOLF-Norrland data over 5 years. A change of OC index or its subscales were regressed against a change of freedom of choice at work, extra work, and ERI adjusted for age, sex, and education. While OC was insensitive to changes in freedom of choice at work and extra work, it was clearly associated with changes of work-related stress over time. Three of four OC subscales exhibited statistically significant associations with ERI. For the first time, we studied fundamental characteristics of OC as an independent personality variable (trait) or an outcome variable subject to changes in the work environment (state). The association between external ERI and OC over time supports our hypothesis of OC being a state. Further investigations are needed to establish OC as a trait or a state.

  13. Monitoring the Relationship Between Changes in Cerebral Oxygenation and Electroencephalography Patterns During Cardiopulmonary Resuscitation: A Feasibility Study.

    PubMed

    Reagan, Elizabeth M; Nguyen, Robert T; Ravishankar, Shreyas T; Chabra, Vikram; Fuentes, Barbara; Spiegel, Rebecca; Parnia, Sam

    2018-05-01

    To date, no studies have examined real-time electroencephalography and cerebral oximetry monitoring during cardiopulmonary resuscitation as markers of the magnitude of global ischemia. We therefore sought to assess the feasibility of combining cerebral oximetry and electroencephalography in patients undergoing cardiopulmonary resuscitation and further to evaluate the electroencephalography patterns during cardiopulmonary resuscitation and their relationship with cerebral oxygenation as measured by cerebral oximetry. Extended case series of in-hospital and out-of-hospital cardiac arrest subjects. Tertiary Medical Center. Inclusion criteria: Convenience sample of 16 patients undergoing cardiopulmonary resuscitation during working hours between March 2014 and March 2015, greater than or equal to 18 years. A portable electroencephalography (Legacy; SedLine, Masimo, Irvine, CA) and cerebral oximetry (Equanox 7600; Nonin Medical, Plymouth, MN) system was used to measure cerebral resuscitation quality. Real-time regional cerebral oxygen saturation and electroencephalography readings were observed during cardiopulmonary resuscitation. The regional cerebral oxygen saturation values and electroencephalography patterns were not used to manage patients by clinical staff. In total, 428 electroencephalography images from 16 subjects were gathered; 40.7% (n = 174/428) were artifactual, therefore 59.3% (n = 254/428) were interpretable. All 16 subjects had interpretable images. Interpretable versus noninterpretable images were not related to a function of time or duration of cardiopulmonary resuscitation but to artifacts that were introduced to the raw data such as diaphoresis, muscle movement, or electrical interference. Interpretable data were able to be obtained immediately after application of the electrode strip. Seven distinct electroencephalography patterns were identified. Voltage suppression was commonest and seen during 78% of overall cardiopulmonary resuscitation time and in 15 of 16 subjects at some point during their cardiopulmonary resuscitation. Other observed patterns and their relative prevalence in relation to overall cardiopulmonary resuscitation time were theta background activity 8%, delta background activity 5%, bi frontotemporal periodic discharge 4%, burst suppression 2%, spike and wave 2%, and rhythmic delta activity 1%. Eight of 16 subjects had greater than one interpretable pattern. At regional cerebral oxygen saturation levels less than or equal to 19%, the observed electroencephalography pattern was exclusively voltage suppression. Delta background activity was only observed at regional cerebral oxygen saturation levels greater than 40%. The remaining patterns were observed throughout regional cerebral oxygen saturation categories above a threshold of 20%. Real-time monitoring of cerebral oxygenation and function during cardiac arrest resuscitation is feasible. Although voltage suppression is the commonest electroencephalography pattern, other distinct patterns exist that may correlate with the quality of cerebral resuscitation and oxygen delivery.

  14. Contribution of urban expansion and a changing climate to decline of a butterfly fauna.

    PubMed

    Casner, Kayce L; Forister, Matthew L; O'Brien, Joshua M; Thorne, James; Waetjen, David; Shapiro, Arthur M

    2014-06-01

    Butterfly populations are naturally patchy and undergo extinctions and recolonizations. Analyses based on more than 2 decades of data on California's Central Valley butterfly fauna show a net loss in species richness through time. We analyzed 22 years of phenological and faunistic data for butterflies to investigate patterns of species richness over time. We then used 18-22 years of data on changes in regional land use and 37 years of seasonal climate data to develop an explanatory model. The model related the effects of changes in land-use patterns, from working landscapes (farm and ranchland) to urban and suburban landscapes, and of a changing climate on butterfly species richness. Additionally, we investigated local trends in land use and climate. A decline in the area of farmland and ranchland, an increase in minimum temperatures during the summer and maximum temperatures in the fall negatively affected net species richness, whereas increased minimum temperatures in the spring and greater precipitation in the previous summer positively affected species richness. According to the model, there was a threshold between 30% and 40% working-landscape area below which further loss of working-landscape area had a proportionally greater effect on butterfly richness. Some of the isolated effects of a warming climate acted in opposition to affect butterfly richness. Three of the 4 climate variables that most affected richness showed systematic trends (spring and summer mean minimum and fall mean maximum temperatures). Higher spring minimum temperatures were associated with greater species richness, whereas higher summer temperatures in the previous year and lower rainfall were linked to lower richness. Patterns of land use contributed to declines in species richness (although the pattern was not linear), but the net effect of a changing climate on butterfly richness was more difficult to discern. © 2014 Society for Conservation Biology.

  15. Sex Differences in Occupational Attainment: A Twelve-Nation Study.

    ERIC Educational Resources Information Center

    Roos, Patricia A.

    Differences in the occupational attainment patterns of men and women were investigated by using data from 12 industrial societies. The sample consisted of employed persons 20 to 64 years of age working full- or part-time in the United States, Australia, Denmark, Finland, West Germany, Great Britain, Netherlands, Northern Ireland, Norway, Sweden,…

  16. Adapting Collaboration Dialogue in Response to Intelligent Tutoring System Feedback

    ERIC Educational Resources Information Center

    Olsen, Jennifer K.; Aleven, Vincent; Rummel, Nikol

    2015-01-01

    To be able to provide better support for collaborative learning in Intelligent Tutoring Systems, it is important to understand how collaboration patterns change. Prior work has looked at the interdependencies between utterances and the change of dialogue over time, but it has not addressed how dialogue changes during a lesson, an analysis that…

  17. Towards an Ethics of Engagement in Education in Global Times

    ERIC Educational Resources Information Center

    Christie, Pam

    2005-01-01

    Starting from the observation that patterns of educational inequality are widely known but largely invisible in public debates on education, this article argues for the importance of an ethics of education which challenges simple acceptance of "things as they are". It suggests possibilities for working with discourses of ethics, rights and…

  18. Local Life Circumstances and Offending Specialization/Versatility: Comparing Opportunity and Propensity Models

    ERIC Educational Resources Information Center

    McGloin, Jean Marie; Sullivan, Christopher J.; Piquero, Alex R.; Pratt, Travis C.

    2007-01-01

    Research has consistently indicated that most offenders demonstrate diversity over the life course. Even so, recent work suggests that offenders tend to illustrate specialization in the short-term, though this specialization diminishes as the "time window" for examining an offending career increases. To examine why this pattern emerges, the…

  19. School Engagement among Urban Youth of Color: Criterion Pattern Effects of Vocational Exploration and Racial Identity

    ERIC Educational Resources Information Center

    Perry, Justin C.

    2008-01-01

    School engagement is a multifaceted psychosocial process that functions as a key mediator of academic achievement, motivation, and school dropout. This study investigated the effects of vocational exploration and racial identity on behavioral (attendance, attention, time spent on class work) and psychological (identification with school) factors…

  20. A comparative study between nonlinear regression and artificial neural network approaches for modelling wild oat (Avena fatua) field emergence

    USDA-ARS?s Scientific Manuscript database

    Non-linear regression techniques are used widely to fit weed field emergence patterns to soil microclimatic indices using S-type functions. Artificial neural networks present interesting and alternative features for such modeling purposes. In this work, a univariate hydrothermal-time based Weibull m...

  1. An Introductory-Geology Exercise on the Polar-Reversal Time Scale.

    ERIC Educational Resources Information Center

    Shea, James Herbert

    1986-01-01

    Presents a three-part exercise which provides undergraduates with opportunities to work with data related to the earth's magnetic field. Includes student materials for activities in determining the history of the earth's magnetic field, in finding the general pattern of declination, and for looking for a polar reversal history. (ML)

  2. Finding More Joy in Teaching Children

    ERIC Educational Resources Information Center

    Baumgartner, Jennifer J.; DiCarlo, Cynthia F.; Apavaloaie, Loredana

    2011-01-01

    Early childhood professionals are familiar with finding and appreciating daily moments of joy. Teachers smile inside and out when toddlers are able to pull up their own pants, preschoolers write their names for the first time, or kindergarteners figure out how to make complicated patterns with blocks. Working with young children can also be very…

  3. Mexican American Adolescents’ Sleep Patterns: Contextual Correlates and Implications for Health and Adjustment in Young Adulthood

    PubMed Central

    Kuo, Sally I-Chun; Updegraff, Kimberly A.; Zeiders, Katharine H.; McHale, Susan M.; Umaña-Taylor, Adriana J.; De Jesús, Sue A. Rodríguez

    2014-01-01

    Late adolescence is a period of substantial risk for unhealthy sleep patterns. This study investigated the contextual correlates and health and adjustment implications of sleep patterns among Mexican American youth (N = 246; 51% female). We focused on Mexican American youth because they represent a large and rapidly increasing subgroup of the U.S. population that is at higher risk for health and adjustment problems; this higher risk may be explained, in part, by sleep patterns. Using data from 7 phone diary interviews conducted when youth averaged 18 years of age, we assessed average nighttime sleep duration and night-to-night variability in sleep duration. Guided by socio-ecological models, we first examined how experiences in the family context (time spent and quality of relationships with parents, parents’ familism values) and in extra-familial contexts (school, work, peers) were related to sleep duration and variability. The findings revealed that time spent in school, work, and with peers linked to less sleep. Further, conflict with mothers was related to greater sleep variability. Next, we tested the implications of sleep in late adolescence for health (perceived physical health, body mass index) and adjustment (depressive symptoms, risky behaviors) in young adulthood. These findings indicated that more sleep variability predicted relative decreases in health and increases in risky behaviors, and shorter sleep duration predicted relative decreases in poorer perceived health for males. The discussion highlights the significance of the transition to young adulthood as a target for sleep research and the importance of studying sleep within its socio-cultural context. PMID:25047598

  4. Corral framework: Trustworthy and fully functional data intensive parallel astronomical pipelines

    NASA Astrophysics Data System (ADS)

    Cabral, J. B.; Sánchez, B.; Beroiz, M.; Domínguez, M.; Lares, M.; Gurovich, S.; Granitto, P.

    2017-07-01

    Data processing pipelines represent an important slice of the astronomical software library that include chains of processes that transform raw data into valuable information via data reduction and analysis. In this work we present Corral, a Python framework for astronomical pipeline generation. Corral features a Model-View-Controller design pattern on top of an SQL Relational Database capable of handling: custom data models; processing stages; and communication alerts, and also provides automatic quality and structural metrics based on unit testing. The Model-View-Controller provides concept separation between the user logic and the data models, delivering at the same time multi-processing and distributed computing capabilities. Corral represents an improvement over commonly found data processing pipelines in astronomysince the design pattern eases the programmer from dealing with processing flow and parallelization issues, allowing them to focus on the specific algorithms needed for the successive data transformations and at the same time provides a broad measure of quality over the created pipeline. Corral and working examples of pipelines that use it are available to the community at https://github.com/toros-astro.

  5. Short-term changes in running mechanics and foot strike pattern after introduction to minimalistic footwear.

    PubMed

    Willson, John D; Bjorhus, Jordan S; Williams, D S Blaise; Butler, Robert J; Porcari, John P; Kernozek, Thomas W

    2014-01-01

    Minimalistic footwear has garnered widespread interest in the running community, based largely on the premise that the footwear may reduce certain running-related injury risk factors through adaptations in running mechanics and foot strike pattern. To examine short-term adaptations in running mechanics among runners who typically run in conventional cushioned heel running shoes as they transition to minimalistic footwear. A 2-week, prospective, observational study. A movement science laboratory. Nineteen female runners with a rear foot strike (RFS) pattern who usually train in conventional running shoes. The participants trained for 20 minutes, 3 times per week for 2 weeks by using minimalistic footwear. Three-dimensional lower extremity running mechanics were analyzed before and after this 2-week period. Hip, knee, and ankle joint kinematics at initial contact; step length; stance time; peak ankle joint moment and joint work; impact peak; vertical ground reaction force loading rate; and foot strike pattern preference were evaluated before and after the intervention. The knee flexion angle at initial contact increased 3.8° (P < .01), but the ankle and hip flexion angles at initial contact did not change after training. No changes in ankle joint kinetics or running temporospatial parameters were observed. The majority of participants (71%), before the intervention, demonstrated an RFS pattern while running in minimalistic footwear. The proportion of runners with an RFS pattern did not decrease after 2 weeks (P = .25). Those runners who chose an RFS pattern in minimalistic shoes experienced a vertical loading rate that was 3 times greater than those who chose to run with a non-RFS pattern. Few systematic changes in running mechanics were observed among participants after 2 weeks of training in minimalistic footwear. The majority of the participants continued to use an RFS pattern after training in minimalistic footwear, and these participants experienced higher vertical loading rates. Continued exposure to these greater loading rates may have detrimental effects over time. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  6. Personal exposure to ultrafine particles: the influence of time-activity patterns.

    PubMed

    Buonanno, G; Stabile, L; Morawska, L

    2014-01-15

    Exposure to ultrafine particles (UFPs) is deemed to be a major risk affecting human health. Therefore, airborne particle studies were performed in the recent years to evaluate the most critical micro-environments, as well as identifying the main UFP sources. Nonetheless, in order to properly evaluate the UFP exposure, personal monitoring is required as the only way to relate particle exposure levels to the activities performed and micro-environments visited. To this purpose, in the present work, the results of experimental analysis aimed at showing the effect of the time-activity patterns on UFP personal exposure are reported. In particular, 24 non-smoking couples (12 during winter and summer time, respectively), comprised of a man who worked full-time and a woman who was a homemaker, were analyzed using personal particle counter and GPS monitors. Each couple was investigated for a 48-h period, during which they also filled out a diary reporting the daily activities performed. Time activity patterns, particle number concentration exposure and the related dose received by the participants, in terms of particle alveolar-deposited surface area, were measured. The average exposure to particle number concentration was higher for women during both summer and winter (Summer: women 1.8 × 10(4) part. cm(-3); men 9.2 × 10(3) part. cm(-3); Winter: women 2.9 × 10(4) part. cm(-3); men 1.3 × 10(4) part. cm(-3)), which was likely due to the time spent undertaking cooking activities. Staying indoors after cooking also led to higher alveolar-deposited surface area dose for both women and men during the winter time (9.12 × 10(2) and 6.33 × 10(2) mm(2), respectively), when indoor ventilation was greatly reduced. The effect of cooking activities was also detected in terms of women's dose intensity (dose per unit time), being 8.6 and 6.6 in winter and summer, respectively. On the contrary, the highest dose intensity activity for men was time spent using transportation (2.8 in both winter and summer). © 2013.

  7. What do ICU doctors do? A multisite time and motion study of the clinical work patterns of registrars.

    PubMed

    Li, Ling; Hains, Isla; Hordern, Toni; Milliss, David; Raper, Ray; Westbrook, Johanna

    2015-09-01

    To quantify the time that intensive care unit registrars spend on different work tasks with other health professionals and patients and using information resources, and to compare them with those of clinicians in general wards and the emergency department (ED). A prospective, observational time-and-motion study of two ICUs with a total of 71 beds at two major teaching hospitals in Sydney. Twenty-six registrars were observed between 08:00 and 18:00 on weekdays for a total of 160.52 hours. Proportions of time spent on different tasks, using specific information resources, working with other health professionals and patients, and rates of multitasking and interruptions. A total of 12 043 distinct tasks were observed. Registrars spent 69.2% of time working at patients' bedsides, 49.6% in professional communication and 39.0% accessing information resources. Half of their time (53.8%) was spent with other ICU doctors and 29.2% with nurses. Compared with doctors and nurses on general wards, and doctors in the ED, ICU registrars were more likely to multitask (40.1 times/hour [24.4% of their time]). ICU registrars had a higher interruption rate than ward clinicians, (4.2 times/hour), but a lower rate than ED doctors. Face-to-face communication and information seeking consume a vast proportion of ICU registrars' time. Multitasking and handling frequent interruptions characterise their work, and such behaviours may create an increased risk of task errors. Electronic clinical information systems may be particularly beneficial in this information-rich environment.

  8. Decoding the spatial signatures of multi-scale climate variability - a climate network perspective

    NASA Astrophysics Data System (ADS)

    Donner, R. V.; Jajcay, N.; Wiedermann, M.; Ekhtiari, N.; Palus, M.

    2017-12-01

    During the last years, the application of complex networks as a versatile tool for analyzing complex spatio-temporal data has gained increasing interest. Establishing this approach as a new paradigm in climatology has already provided valuable insights into key spatio-temporal climate variability patterns across scales, including novel perspectives on the dynamics of the El Nino Southern Oscillation or the emergence of extreme precipitation patterns in monsoonal regions. In this work, we report first attempts to employ network analysis for disentangling multi-scale climate variability. Specifically, we introduce the concept of scale-specific climate networks, which comprises a sequence of networks representing the statistical association structure between variations at distinct time scales. For this purpose, we consider global surface air temperature reanalysis data and subject the corresponding time series at each grid point to a complex-valued continuous wavelet transform. From this time-scale decomposition, we obtain three types of signals per grid point and scale - amplitude, phase and reconstructed signal, the statistical similarity of which is then represented by three complex networks associated with each scale. We provide a detailed analysis of the resulting connectivity patterns reflecting the spatial organization of climate variability at each chosen time-scale. Global network characteristics like transitivity or network entropy are shown to provide a new view on the (global average) relevance of different time scales in climate dynamics. Beyond expected trends originating from the increasing smoothness of fluctuations at longer scales, network-based statistics reveal different degrees of fragmentation of spatial co-variability patterns at different scales and zonal shifts among the key players of climate variability from tropically to extra-tropically dominated patterns when moving from inter-annual to decadal scales and beyond. The obtained results demonstrate the potential usefulness of systematically exploiting scale-specific climate networks, whose general patterns are in line with existing climatological knowledge, but provide vast opportunities for further quantifications at local, regional and global scales that are yet to be explored.

  9. Sleep patterns and sleepiness among young students: A longitudinal study before and after admission as trainees and apprentices.

    PubMed

    Fischer, Frida Marina; Wey, Daniela; Valente, Daniel; Luz, Andréa Aparecida da; Pinheiro, Fernando; Fonseca, Barbara Cristina; Silva-Costa, Aline; Moreno, Claudia Roberta; Menna-Barreto, Luiz; Teixeira, Liliane Reis

    2015-05-01

    In developing countries, youngsters start to work during the high school years. Several studies have shown the difficulties associated with double shift, i.e. to work and study concomitantly, and its negative health consequences. Work and study time, as social synchronizers, have significant effects on the sleep-wake cycle (SWC). The purpose of this study was to evaluate sleep patterns and sleepiness in young students before and after entering the workforce as apprentices or trainees. Participants were 40 adolescents (26 males), 15-18 years old (mean = 15.8 years old) engaged in a first-job program at a non-governmental organization (NGO) while attending evening high school in the outskirts of the city of São Paulo, Brazil. The participants wore actigraphs (Ambulatory Monitoring, Inc.) and registered subjective sleepiness on KSS (Karolinska Sleepiness Scale) along 7 consecutive days, before and after admission to the job. Descriptive analyses were performed, and the variables were tested by means of the t-test and repeated measures ANOVA taking factors day of the week and time of the day into consideration. The participants' sleep duration on weekdays exhibited significant difference before and after starting work (F = 4.55; p = 0.04); the mean sleep duration was 492 min (SD = 44 min) before admission to the job to decrease to 405 min (SD = 58 min) after starting work. The mid-sleep time exhibited significant difference on weekdays before and after starting work (04:57 h; SD = 45 min versus 03:30 h; SD = 54 min; F = 4.91; p = 0.03). Finally, also sleepiness on weekdays (F = 6.41; p = 0.04) and at the waking time (F = 10.75; p < 0.01) exhibited significant difference before and after admission to the job. This article emphasizes the fact that social synchronizers like working during the day and studying in the evening changed the participants' SWC and were associated with sleep restriction. Brazilian governmental incentives notwithstanding, simultaneous performance of several activities by young workers should be considered as an occupational health hazard. Employment policies targeting young workers should take the dual shift - study and work - and its effects on the sleep-wake cycle into account.

  10. Emergence of flagellar beating from the collective behavior of individual ATP-powered dyneins

    NASA Astrophysics Data System (ADS)

    Namdeo, S.; Onck, P. R.

    2016-10-01

    Flagella are hair-like projections from the surface of eukaryotic cells, and they play an important role in many cellular functions, such as cell-motility. The beating of flagella is enabled by their internal architecture, the axoneme, and is powered by a dense distribution of motor proteins, dyneins. The dyneins deliver the required mechanical work through the hydrolysis of ATP. Although the dynein-ATP cycle, the axoneme microstructure, and the flagellar-beating kinematics are well studied, their integration into a coherent picture of ATP-powered flagellar beating is still lacking. Here we show that a time-delayed negative-work-based switching mechanism is able to convert the individual sliding action of hundreds of dyneins into a regular overall beating pattern leading to propulsion. We developed a computational model based on a minimal representation of the axoneme consisting of two representative doublet microtubules connected by nexin links. The relative sliding of the microtubules is incorporated by modeling two groups of ATP-powered dyneins, each responsible for sliding in opposite directions. A time-delayed switching mechanism is postulated, which is key in converting the local individual sliding action of multiple dyneins into global beating. Our results demonstrate that an overall nonreciprocal beating pattern can emerge with time due to the spatial and temporal coordination of the individual dyneins. These findings provide insights in the fundamental working mechanism of axonemal dyneins and could possibly open new research directions in the field of flagellar motility.

  11. Emergence of flagellar beating from the collective behavior of individual ATP-powered dyneins.

    PubMed

    Namdeo, S; Onck, P R

    2016-10-01

    Flagella are hair-like projections from the surface of eukaryotic cells, and they play an important role in many cellular functions, such as cell-motility. The beating of flagella is enabled by their internal architecture, the axoneme, and is powered by a dense distribution of motor proteins, dyneins. The dyneins deliver the required mechanical work through the hydrolysis of ATP. Although the dynein-ATP cycle, the axoneme microstructure, and the flagellar-beating kinematics are well studied, their integration into a coherent picture of ATP-powered flagellar beating is still lacking. Here we show that a time-delayed negative-work-based switching mechanism is able to convert the individual sliding action of hundreds of dyneins into a regular overall beating pattern leading to propulsion. We developed a computational model based on a minimal representation of the axoneme consisting of two representative doublet microtubules connected by nexin links. The relative sliding of the microtubules is incorporated by modeling two groups of ATP-powered dyneins, each responsible for sliding in opposite directions. A time-delayed switching mechanism is postulated, which is key in converting the local individual sliding action of multiple dyneins into global beating. Our results demonstrate that an overall nonreciprocal beating pattern can emerge with time due to the spatial and temporal coordination of the individual dyneins. These findings provide insights in the fundamental working mechanism of axonemal dyneins and could possibly open new research directions in the field of flagellar motility.

  12. Time of Day and Day of Week Trends in EMS Demand.

    PubMed

    Cantwell, Kate; Morgans, Amee; Smith, Karen; Livingston, Michael; Spelman, Tim; Dietze, Paul

    2015-01-01

    We examined temporal variations in overall Emergency Medical Services (EMS) demand, as well as medical and trauma cases separately. We analyzed cases according to time of day and day of week to determine whether population level demand demonstrates temporal patterns that will increase baseline knowledge for EMS planning. We conducted a secondary analysis of data from the Ambulance Victoria data warehouse covering the period 2008-2011. We included all cases of EMS attendance which resulted in 1,203,803 cases for review. Data elements comprised age, gender, date and time of call to the EMS emergency number along with the clinical condition of the patient. We employed Poisson regression to analyze case numbers and trigonometric regression to quantify distribution patterns. EMS demand exhibited a bimodal distribution with the highest peak at 10:00 and a second smaller peak at 19:00. The highest number of cases occurred on Fridays, and the lowest on Tuesdays and Wednesdays. However, the distribution of cases throughout the day differed by day of week. Distribution patterns on Fridays, Saturdays and Sundays differed significantly from the rest of the week (p < 0.001). When categorized into medical or trauma cases, medical cases were more frequent during working hours and involved patients of higher mean age (57 years vs. 49 years for trauma, p < 0.001). Trauma cases peaked on Friday and Saturday nights around midnight. Day of week EMS demand distribution patterns reveal differences that can be masked in aggregate data. Day of week EMS demand distribution patterns showed not only which days have differences in demand but the times of day at which the demand changes. Patterns differed by case type as well. These differences in distribution are important for EMS demand planning. Increased understanding of EMS demand patterns is imperative in a climate of ever-increasing demand and fiscal constraints. Further research is needed into the effect of age and case type on EMS demand.

  13. Effects of parents and Brown-headed Cowbirds (Molothrus ater) on nest predation risk for a songbird

    PubMed Central

    Latif, Quresh S; Heath, Sacha K; Rotenberry, John T

    2012-01-01

    Nest predation limits avian fitness, so ornithologists study nest predation, but they often only document patterns of predation rates without substantively investigating underlying mechanisms. Parental behavior and predator ecology are two fundamental drivers of predation rates and patterns, but the role of parents is less certain, particularly for songbirds. Previous work reproduced microhabitat-predation patterns experienced by Yellow Warblers (Setophaga petechia) in the Mono Lake basin at experimental nests without parents, suggesting that these patterns were driven by predator ecology rather than predator interactions with parents. In this study, we further explored effects of post-initiation parental behavior (nest defense and attendance) on predation risk by comparing natural versus experimental patterns related to territory density, seasonal timing of nest initiation, and nest age. Rates of parasitism by Brown-headed Cowbirds (Molothrus ater) were high in this system (49% nests parasitized), so we also examined parasitism-predation relationships. Natural nest predation rates (NPR) correlated negatively with breeding territory density and nonlinearly (U-shaped relationship) with nest-initiation timing, but experimental nests recorded no such patterns. After adjusting natural-nest data to control for these differences from experimental nests other than the presence of parents (e.g., defining nest failure similarly and excluding nestling-period data), we obtained similar results. Thus, parents were necessary to produce observed patterns. Lower natural NPR compared with experimental NPR suggested that parents reduced predation rates via nest defense, so this parental behavior or its consequences were likely correlated with density or seasonal timing. In contrast, daily predation rates decreased with nest age for both nest types, indicating this pattern did not involve parents. Parasitized nests suffered higher rates of partial predation but lower rates of complete predation, suggesting direct predation by cowbirds. Explicit behavioral research on parents, predators (including cowbirds), and their interactions would further illuminate mechanisms underlying the density, seasonal, and nest age patterns we observed. PMID:23301174

  14. Comparison of extrinsic and intrinsic neuromodulation in two central pattern generator circuits in invertebrates.

    PubMed

    Katz, P S

    1998-05-01

    There are many sources of modulatory input to CPGs and other types of neuronal circuits. These inputs can change the properties of cells and synapses and dramatically alter the production of motor patterns. Sometimes this enables the production of motor patterns by the circuit. At other times, the modulation allows alternate motor patterns to be produced by a single circuit. Modulatory neurones have fast as well as slow actions. In some cases, such as with GPR, the two types of effects are due to the release of co-transmitters. In other cases, such as with the DSIs, a single substance can act at different receptors to cause fast and slow postsynaptic actions. The effect of a neuromodulatory neurone is determined by the type of receptor on the target neurone. Thus a single modulatory neurone evokes a suite of actions in a circuit and thereby produces a co-ordinated output. Extrinsic and intrinsic sources of neuromodulation have different sets of constraints acting upon them. For example, extrinsic neuromodulation can easily be used for motor pattern selection; a different pattern is produced depending upon which modulatory inputs are active. However, intrinsic neuromodulation is not well suited to that task. Instead, it is useful for self-organizing properties and experience-dependent effects. One clear conclusion from this work and other work in the field is that neuromodulation by neurones intrinsic and extrinsic to CPGs is not uncommon (Katz, 1995; Katz & Frost, 1996). It is part of the normal process of motor pattern generation. As such, it needs to be considered when discussing mechanisms for neuronal circuit actions.

  15. Finite-time barriers to reaction front propagation

    NASA Astrophysics Data System (ADS)

    Locke, Rory; Mahoney, John; Mitchell, Kevin

    2015-11-01

    Front propagation in advection-reaction-diffusion systems gives rise to rich geometric patterns. It has been shown for time-independent and time-periodic fluid flows that invariant manifolds, termed burning invariant manifolds (BIMs), serve as one-sided dynamical barriers to the propagation of reaction front. More recently, theoretical work has suggested that one-sided barriers, termed burning Lagrangian Coherent structures (bLCSs), exist for fluid velocity data prescribed over a finite time interval, with no assumption on the time-dependence of the flow. In this presentation, we use a time-varying fluid ``wind'' in a double-vortex channel flow to demonstrate that bLCSs form the (locally) most attracting or repelling fronts.

  16. Blood drop patterns: Formation and applications.

    PubMed

    Chen, Ruoyang; Zhang, Liyuan; Zang, Duyang; Shen, Wei

    2016-05-01

    The drying of a drop of blood or plasma on a solid substrate leads to the formation of interesting and complex patterns. Inter- and intra-cellular and macromolecular interactions in the drying plasma or blood drop are responsible for the final morphologies of the dried patterns. Changes in these cellular and macromolecular components in blood caused by diseases have been suspected to cause changes in the dried drop patterns of plasma and whole blood, which could be used as simple diagnostic tools to identify the health of humans and livestock. However, complex physicochemical driving forces involved in the pattern formation are not fully understood. This review focuses on the scientific development in microscopic observations and pattern interpretation of dried plasma and whole blood samples, as well as the diagnostic applications of pattern analysis. Dried drop patterns of plasma consist of intricate visible cracks in the outer region and fine structures in the central region, which are mainly influenced by the presence and concentration of inorganic salts and proteins during drying. The shrinkage of macromolecular gel and its adhesion to the substrate surface have been thought to be responsible for the formation of the cracks. Dried drop patterns of whole blood have three characteristic zones; their formation as functions of drying time has been reported in the literature. Some research works have applied engineering treatment to the evaporation process of whole blood samples. The sensitivities of the resultant patterns to the relative humidity of the environment, the wettability of the substrates, and the size of the drop have been reported. These research works shed light on the mechanisms of spreading, evaporation, gelation, and crack formation of the blood drops on solid substrates, as well as on the potential applications of dried drop patterns of plasma and whole blood in diagnosis. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  17. Pediatrician's practice choices: differences between part-time and full-time practice.

    PubMed

    Fritz, N E; Lantos, J D

    1991-10-01

    A national survey was used to study the differences in career and family patterns of pediatricians who work part-time (PT) vs those who work full-time (FT). A questionnaire mailed to 375 members of the American Academy of Pediatrics asked about age, marital status, number of children, type of practice, hours worked in particular duties, and attitudes about their choices. Sixty-five percent (n = 216) of the questionnaires were completed. The mean age of both the PT and FT women was 40 years, and FT men averaged 46 years. Thirty-seven percent of women had worked PT at some point in their careers; 21% were currently working PT. Only 70% of the FT women were married compared with 97% and 95% of PT women and FT men. The FT women had significantly fewer children (mean 1.27, compared with 2.34 for PT women and 2.39 for FT men). Part-time women in academic medicine tended to do little research or administrative work, but they had more teaching responsibilities. Almost all the PT women were happy with their decisions and careers despite the feeling among many that they had made career compromises. Many of the FT pediatricians wanted to work less. It is concluded that many women, particularly those with children, choose PT work in order to combine career and family duties. These choices may lead to different career paths for women pediatricians. By recognizing these different career paths, it may be possible for academic institutions to benefit from the unique contributions that PT women pediatricians can make.

  18. Radiofrequency identification: exploiting an old technology for measuring nurse time and motion.

    PubMed

    Jones, Terry L

    2012-09-01

    A national campaign is underway to increase the amount of time staff nurses spend at the bedside of hospitalized patients through redesign of the work environment. This kind of work redesign requires robust data depicting what nurses do and how they spend their time. Historically, these kinds of data have been difficult, costly, and time consuming to collect. Wireless capture of data on the movement of humans within the work environment (ie, time and motion) is now possible through radiofrequency identification technology. When small tracking devices the size of a quarter are affixed to their clothing, the movement of nurses throughout a patient care unit can be monitored. The duration and frequency of patient interaction are captured along with the duration of time spent in other locations of interest to include nurses' station, supply room, medication room, doctors' station, electronic documentation stations, family waiting rooms, and the hallway. Patterns of nurse movement and time allocation can be efficiently identified, and the effects of staffing practices, workflows, and unit layout evaluated. Integration of radiofrequency identification time and motion data with other databases enables nurse leaders to link nursing time to important cost and quality outcomes. Nurse leaders should explore the usefulness of radiofrequency identification technology in addressing data needs for nurse time and motion.

  19. Baselining PMU Data to Find Patterns and Anomalies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Amidan, Brett G.; Follum, James D.; Freeman, Kimberly A.

    This paper looks at the application of situational awareness methodologies with respect to power grid data. These methodologies establish baselines that look for typical patterns and atypical behavior in the data. The objectives of the baselining analyses are to provide: real-time analytics, the capability to look at historical trends and events, and reliable predictions of the near future state of the grid. Multivariate algorithms were created to establish normal baseline behavior and then score each moment in time according to its variance from the baseline. Detailed multivariate analytical techniques are described in this paper that produced ways to identify typicalmore » patterns and atypical behavior. In this case, atypical behavior is behavior that is unenvisioned. Visualizations were also produced to help explain the behavior that was identified mathematically. Examples are shown to help describe how to read and interpret the analyses and visualizations. Preliminary work has been performed on PMU data sets from BPA (Bonneville Power Administration) and EI (Eastern Interconnect). Actual results are not fully shown here because of confidentiality issues. Comparisons between atypical events found mathematically and actual events showed that many of the actual events are also atypical events; however there are many atypical events that do not correlate to any actual events. Additional work needs to be done to help classify the atypical events into actual events, so that the importance of the events can be better understood.« less

  20. Modeling eye gaze patterns in clinician-patient interaction with lag sequential analysis.

    PubMed

    Montague, Enid; Xu, Jie; Chen, Ping-Yu; Asan, Onur; Barrett, Bruce P; Chewning, Betty

    2011-10-01

    The aim of this study was to examine whether lag sequential analysis could be used to describe eye gaze orientation between clinicians and patients in the medical encounter. This topic is particularly important as new technologies are implemented into multiuser health care settings in which trust is critical and nonverbal cues are integral to achieving trust. This analysis method could lead to design guidelines for technologies and more effective assessments of interventions. Nonverbal communication patterns are important aspects of clinician-patient interactions and may affect patient outcomes. The eye gaze behaviors of clinicians and patients in 110 videotaped medical encounters were analyzed using the lag sequential method to identify significant behavior sequences. Lag sequential analysis included both event-based lag and time-based lag. Results from event-based lag analysis showed that the patient's gaze followed that of the clinician, whereas the clinician's gaze did not follow the patient's. Time-based sequential analysis showed that responses from the patient usually occurred within 2 s after the initial behavior of the clinician. Our data suggest that the clinician's gaze significantly affects the medical encounter but that the converse is not true. Findings from this research have implications for the design of clinical work systems and modeling interactions. Similar research methods could be used to identify different behavior patterns in clinical settings (physical layout, technology, etc.) to facilitate and evaluate clinical work system designs.

  1. Modeling Eye Gaze Patterns in Clinician-Patient Interaction with Lag Sequential Analysis

    PubMed Central

    Montague, E; Xu, J; Asan, O; Chen, P; Chewning, B; Barrett, B

    2011-01-01

    Objective The aim of this study was to examine whether lag-sequential analysis could be used to describe eye gaze orientation between clinicians and patients in the medical encounter. This topic is particularly important as new technologies are implemented into multi-user health care settings where trust is critical and nonverbal cues are integral to achieving trust. This analysis method could lead to design guidelines for technologies and more effective assessments of interventions. Background Nonverbal communication patterns are important aspects of clinician-patient interactions and may impact patient outcomes. Method Eye gaze behaviors of clinicians and patients in 110-videotaped medical encounters were analyzed using the lag-sequential method to identify significant behavior sequences. Lag-sequential analysis included both event-based lag and time-based lag. Results Results from event-based lag analysis showed that the patients’ gaze followed that of clinicians, while clinicians did not follow patients. Time-based sequential analysis showed that responses from the patient usually occurred within two seconds after the initial behavior of the clinician. Conclusion Our data suggest that the clinician’s gaze significantly affects the medical encounter but not the converse. Application Findings from this research have implications for the design of clinical work systems and modeling interactions. Similar research methods could be used to identify different behavior patterns in clinical settings (physical layout, technology, etc.) to facilitate and evaluate clinical work system designs. PMID:22046723

  2. The Ultrasonic Directional Tidal Breathing Pattern Sensor: Equitable Design Realization Based on Phase Information

    PubMed Central

    Sinharay, Arijit; Rakshit, Raj; Chakravarty, Tapas; Ghosh, Deb; Pal, Arpan

    2017-01-01

    Pulmonary ailments are conventionally diagnosed by spirometry. The complex forceful breathing maneuver as well as the extreme cost of spirometry renders it unsuitable in many situations. This work is aimed to facilitate an emerging direction of tidal breathing-based pulmonary evaluation by designing a novel, equitable, precise and portable device for acquisition and analysis of directional tidal breathing patterns, in real time. The proposed system primarily uses an in-house designed blow pipe, 40-kHz air-coupled ultrasound transreceivers, and a radio frequency (RF) phase-gain integrated circuit (IC). Moreover, in order to achieve high sensitivity in a cost-effective design philosophy, we have exploited the phase measurement technique, instead of selecting the contemporary time-of-flight (TOF) measurement; since application of the TOF principle in tidal breathing assessments requires sub-micro to nanosecond time resolution. This approach, which depends on accurate phase measurement, contributed to enhanced sensitivity using a simple electronics design. The developed system has been calibrated using a standard 3-L calibration syringe. The parameters of this system are validated against a standard spirometer, with maximum percentage error below 16%. Further, the extracted respiratory parameters related to tidal breathing have been found to be comparable with relevant prior works. The error in detecting respiration rate only is 3.9% compared to manual evaluation. These encouraging insights reveal the definite potential of our tidal breathing pattern (TBP) prototype for measuring tidal breathing parameters in order to extend the reach of affordable healthcare in rural regions and developing areas. PMID:28800103

  3. Global temperature patterns 6000 years ago. Progress report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Webb, T. III

    The overall goal is to illustrate the climatic patterns of 5000 to 7000 years ago over as wide an area of the northern hemisphere as possible. Mapping of the patterns in selected climatic variables at 5000 to 7000 years ago that can be reconstructed from pollen and marine-plankton data is planned. Multivariate statistical methods permit using the modern distribution of these data in order to transform their fossil remains into climate estimates of past times. Given these goals and methods, research during the first eight months focused on assembling the available modern and fossil data from each of the mainmore » areas under study. Two workshop conferences were held to help organize the joint work.« less

  4. Interfacial patterns in magnetorheological fluids: Azimuthal field-induced structures.

    PubMed

    Dias, Eduardo O; Lira, Sérgio A; Miranda, José A

    2015-08-01

    Despite their practical and academic relevance, studies of interfacial pattern formation in confined magnetorheological (MR) fluids have been largely overlooked in the literature. In this work, we present a contribution to this soft matter research topic and investigate the emergence of interfacial instabilities when an inviscid, initially circular bubble of a Newtonian fluid is surrounded by a MR fluid in a Hele-Shaw cell apparatus. An externally applied, in-plane azimuthal magnetic field produced by a current-carrying wire induces interfacial disturbances at the two-fluid interface, and pattern-forming structures arise. Linear stability analysis, weakly nonlinear theory, and a vortex sheet approach are used to access early linear and intermediate nonlinear time regimes, as well as to determine stationary interfacial shapes at fully nonlinear stages.

  5. Workplace harassment patterning, gender, and utilization of professional services: findings from a US national study.

    PubMed

    Shannon, Candice A; Rospenda, Kathleen M; Richman, Judith A

    2007-03-01

    This study constitutes the first national longitudinal survey to address the relationship between workplace harassment and service utilization. We examine how patterns of sexual harassment and generalized workplace harassment are linked to utilization of mental health, health, legal, spiritual, and work-related services, and whether and how gender influences these relationships. Data derive from a random digit dial telephone survey with a continental US sample of employed adults. Eligibility criteria were being 18 years of age or over, and being employed at least 20 h per week at some time in the 12 months prior to the wave 1 survey. Out of 4116 households with eligible individuals, 2151 agreed to participate at wave 1. At wave 2, 1418 participated, thus, the overall response rate was 34.5%. We show that the patterning of workplace harassment over two time points (chronic, remission, onset, never harassed) is associated with the use of different types of services. Gender partially moderated the relationship between workplace harassment and services.

  6. Enhanced pattern resolution, swelling-behaviour and biocompatibility of bioimprinted casein microdevices

    NASA Astrophysics Data System (ADS)

    Hashemi, Azadeh; de Decker, Fanny; Orcheston-Findlay, Louise; Ali, M. Azam; Alkaisi, Maan M.; Nock, Volker

    2017-11-01

    This work introduces casein microstructures with surface features as a biodegradable biomedical platform technology for enhancing tissue-engineering applications. An optimized fabrication process is presented to reduce the hydrophobicity of intermediate polydimethylsiloxane (PDMS) molds and to transfer high-resolution regular and biomimetic features onto the surface of casein devices. Four different cross-linking reagents, glutaraldehyde, formaldehyde, citric acid and transglutaminase (TG) were investigated to increase the degradation time of casein and their influence on swelling and biocompatibility of the films was studied. TG was found to be the only cross-linker to effectively increase the degradation time and show reduced film swelling after immersion into media, while remaining compatible with cell-culture. The maximum expansion of the films cross-linked via TG was 33% after 24 hours of immersion in cell-culture media. C2C12 cells were successfully cultured on the patterned films for up to 72 hours. The patterned biodegradable casein substrates presented here have promising applications in stem-cell engineering, regenerative medicine, and implantable devices.

  7. TopoToolbox: using sensor topography to calculate psychologically meaningful measures from event-related EEG/MEG.

    PubMed

    Tian, Xing; Poeppel, David; Huber, David E

    2011-01-01

    The open-source toolbox "TopoToolbox" is a suite of functions that use sensor topography to calculate psychologically meaningful measures (similarity, magnitude, and timing) from multisensor event-related EEG and MEG data. Using a GUI and data visualization, TopoToolbox can be used to calculate and test the topographic similarity between different conditions (Tian and Huber, 2008). This topographic similarity indicates whether different conditions involve a different distribution of underlying neural sources. Furthermore, this similarity calculation can be applied at different time points to discover when a response pattern emerges (Tian and Poeppel, 2010). Because the topographic patterns are obtained separately for each individual, these patterns are used to produce reliable measures of response magnitude that can be compared across individuals using conventional statistics (Davelaar et al. Submitted and Huber et al., 2008). TopoToolbox can be freely downloaded. It runs under MATLAB (The MathWorks, Inc.) and supports user-defined data structure as well as standard EEG/MEG data import using EEGLAB (Delorme and Makeig, 2004).

  8. Limited Engagements? Women’s and Men’s Work/Volunteer Time in the Encore Life Course Stage

    PubMed Central

    Moen, Phyllis; Flood, Sarah

    2013-01-01

    Americans are living healthier and longer lives, but the shifting age distribution is straining existing and projected social welfare protections for older adults (e.g., Social Security, Medicare). One solution is to delay retirement. Another is an alternative to “total leisure” retirement -- an “encore” stage of paid or unpaid engagement coming after career jobs but before infirmities associated with old age. We draw on gendered life-course themes together with data from the American Time Use Survey (2003–2009) to examine the real time American men and women ages 50–75 apportion to paid work and unpaid volunteer work on an average day, as well as factors predicting their time allocations. We find that while full-time employment declines after the 50s, many Americans allot time to more limited engagements – working part time, being self-employed, volunteering, helping out – through and even beyond their 60s. Caring for a child or infirm adult reduces the odds of paid work but not volunteering. While time working for pay declines with age (though more slowly for men than women), time volunteering does not. Older men and women in poor health, without a college degree, with a disability or SSI income are the least likely to be publicly engaged. This social patterning illustrates that while the ideal of an encore of paid or unpaid voluntary, flexible, and meaningful engagement is an emerging reality for some, it appears less attainable for others. This suggests the importance of organizational and public policy innovations offering all Americans a range of encore opportunities. PMID:24273348

  9. Maternal employment, acculturation, and time spent in food-related behaviors among Hispanic mothers in the United States. Evidence from the American Time Use Survey.

    PubMed

    Sliwa, Sarah A; Must, Aviva; Peréa, Flavia; Economos, Christina D

    2015-04-01

    Employment is a major factor underlying im/migration patterns. Unfortunately, lower diet quality and higher rates of obesity appear to be unintended consequences of moving to the US. Changes in food preparation practices may be a factor underlying dietary acculturation. The relationships between employment, acculturation, and food-related time use in Hispanic families have received relatively little attention. We used cross-sectional data collected from Hispanic mothers (ages 18-65) with at least one child <13 years old participating in the 2003-2011 American Time Use Survey (n = 3622) to estimate the relationship between employment, acculturation (US-born vs. im/migrant), and time spent in food preparation and family dinner. Regression models were estimated separately for the employed and the non-working and were adjusted for Hispanic origin group, socio-demographic and household characteristics. Working an eight-hour day was associated with spending 38 fewer minutes in food preparation (-38.0 ± SE 4.8, p < 001). Although being US-born was associated with spending fewer minutes in food preparation, this relationship varied by origin group. Acculturation did not appear to modify the relationship between hours worked and time spent in food preparation or family dinner. Mothers who worked late hours spent less time eating the evening meal with their families (-9.8 ± SE 1.3). Although an eight-hour workday was associated with a significant reduction in food preparation time, an unexpected result is that, for working mothers, additional time spent in paid work is not associated with the duration of family dinner later that day. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Use Patterns of Leave-on Personal Care Products among Swiss-German Children, Adolescents, and Adults

    PubMed Central

    Manová, Eva; von Goetz, Natalie; Keller, Carmen; Siegrist, Michael; Hungerbühler, Konrad

    2013-01-01

    In order to model exposure to ingredients contained in personal care products (PCPs) and assess their potential risks to human health, access to reliable PCP use data, including co-use patterns, is essential. A postal questionnaire survey was conducted to determine the use patterns of eight leave-on PCP categories among the German-speaking population of Switzerland (N = 1,196; ages 0–97 years), providing for the first time in Europe PCP use data for children <12 years of age. The majority of respondents (99%) reported having used at least one of the investigated PCP categories in the past year. Co-use of two or more PCP categories at the same time was common and more complex amongst adults. Regular use of face cream and body lotion was very high in the youngest group of children aged 0–4 years (more than 79% respondents) who may be more vulnerable to certain adverse effects of some PCP ingredients. A comparison with previously collected information on PCP use patterns in Germany and the Netherlands indicates differences in PCP use patterns among European consumers and suggests that surrogate PCP use data from other countries must be used with caution. This work extends the existing knowledge of PCP use patterns and will be useful for new exposure assessments for ingredients contained in PCPs used by the young consumers. PMID:23823714

  11. Gene expression analysis of the ovary of hybrid females of Xenopus laevis and X. muelleri

    PubMed Central

    2008-01-01

    Background Interspecific hybrids of frogs of the genus Xenopus result in sterile hybrid males and fertile hybrid females. Previous work has demonstrated a dramatic asymmetrical pattern of misexpression in hybrid males compared to the two parental species with relatively few genes misexpressed in comparisons of hybrids and the maternal species (X. laevis) and dramatically more genes misexpressed in hybrids compared to the paternal species (X. muelleri). In this work, we examine the gene expression pattern in hybrid females of X. laevis × X. muelleri to determine if this asymmetrical pattern of expression also occurs in hybrid females. Results We find a similar pattern of asymmetry in expression compared to males in that there were more genes differentially expressed between hybrids and X. muelleri compared to hybrids and X. laevis. We also found a dramatic increase in the number of misexpressed genes with hybrid females having about 20 times more genes misexpressed in ovaries compared to testes of hybrid males and therefore the match between phenotype and expression pattern is not supported. Conclusion We discuss these intriguing findings in the context of reproductive isolation and suggest that divergence in female expression may be involved in sterility of hybrid males due to the inherent sensitivity of spermatogenesis as defined by the faster male evolution hypothesis for Haldane's rule. PMID:18331635

  12. Spatially aggregated multiclass pattern classification in functional MRI using optimally selected functional brain areas.

    PubMed

    Zheng, Weili; Ackley, Elena S; Martínez-Ramón, Manel; Posse, Stefan

    2013-02-01

    In previous works, boosting aggregation of classifier outputs from discrete brain areas has been demonstrated to reduce dimensionality and improve the robustness and accuracy of functional magnetic resonance imaging (fMRI) classification. However, dimensionality reduction and classification of mixed activation patterns of multiple classes remain challenging. In the present study, the goals were (a) to reduce dimensionality by combining feature reduction at the voxel level and backward elimination of optimally aggregated classifiers at the region level, (b) to compare region selection for spatially aggregated classification using boosting and partial least squares regression methods and (c) to resolve mixed activation patterns using probabilistic prediction of individual tasks. Brain activation maps from interleaved visual, motor, auditory and cognitive tasks were segmented into 144 functional regions. Feature selection reduced the number of feature voxels by more than 50%, leaving 95 regions. The two aggregation approaches further reduced the number of regions to 30, resulting in more than 75% reduction of classification time and misclassification rates of less than 3%. Boosting and partial least squares (PLS) were compared to select the most discriminative and the most task correlated regions, respectively. Successful task prediction in mixed activation patterns was feasible within the first block of task activation in real-time fMRI experiments. This methodology is suitable for sparsifying activation patterns in real-time fMRI and for neurofeedback from distributed networks of brain activation. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Motif-Synchronization: A new method for analysis of dynamic brain networks with EEG

    NASA Astrophysics Data System (ADS)

    Rosário, R. S.; Cardoso, P. T.; Muñoz, M. A.; Montoya, P.; Miranda, J. G. V.

    2015-12-01

    The major aim of this work was to propose a new association method known as Motif-Synchronization. This method was developed to provide information about the synchronization degree and direction between two nodes of a network by counting the number of occurrences of some patterns between any two time series. The second objective of this work was to present a new methodology for the analysis of dynamic brain networks, by combining the Time-Varying Graph (TVG) method with a directional association method. We further applied the new algorithms to a set of human electroencephalogram (EEG) signals to perform a dynamic analysis of the brain functional networks (BFN).

  14. Team-level flexibility, work-home spillover, and health behavior.

    PubMed

    Moen, Phyllis; Fan, Wen; Kelly, Erin L

    2013-05-01

    Drawing on two waves of survey data conducted six months apart in 2006, this study examined the impacts of a team-level flexibility initiative (ROWE--results only work environment) on changes in the work-home spillover and health behavior of employees at the Midwest headquarters of a large U.S. corporation. Using cluster analysis, we identified three distinct baseline spillover constellations: employees with high negative spillover, high positive spillover, and low overall spillover. Within-team spillover measures were highly intercorrelated, suggesting that work teams as well as individuals have identifiable patterns of spillover. Multilevel analyses showed ROWE reduced individual- and team-level negative work-home spillover but not positive work-home spillover or spillover from home-to-work. ROWE also promoted employees' health behaviors: increasing the odds of quitting smoking, decreasing smoking frequency, and promoting perceptions of adequate time for healthy meals. Trends suggest that ROWE also decreased the odds of excessive drinking and improved sleep adequacy and exercise frequency. Some health behavior effects were mediated via reduced individual-level negative work-home spillover (exercise frequency, adequate time for sleep) and reduced team-level negative work-home spillover (smoking frequency, exercise frequency, and adequate time for sleep). While we found no moderating effects of gender, ROWE especially improved the exercise frequency of singles and reduced the smoking frequency of employees with low overall spillover at baseline. Copyright © 2013. Published by Elsevier Ltd.

  15. [Associations among physical condition, life hour, and dietary intake male Japanese shift workers: physical condition and lifestyle survey of male Japanese shift workers].

    PubMed

    Fukumura, Tomoe; Yoshita, Katsushi; Tabata, Masaji

    2015-01-01

    The purpose of this study was to understand the actual state of life hours (working time, sleep time, and time of meal intake) and dietary habits of male shift work employees, and to elucidate the impact of working arrangements and dietary habits on their physical condition and health problems. The subjects were 187 male employees (aged 18-64 years) working for an industrial company in Toyama prefecture. We used a self-administered questionnaire to assess dietary habit, lifestyle habits, and life hours at the time of a periodic health examination in April 2013. The subjects were grouped based on their working condition (i.e., day shift, late shift, and late-night shift) into two groups of day shift (n = 107) and shiftwork (n = 80). The proportion of time spent sleeping and feeding was determined in half hour increments, and the incidences of skipping meals (breakfast, lunch and dinner) and midnight snack intake were calculated for each working condition. We also examined the association between the frequency of eating and physical condition for each working condition. The state of life hours of the shiftwork group during the day was similar to that of the day shift group. However, the workers' state of life hours, incidences of skipping meals, and midnight snack intake varied considerably when working at the other shift times. In the shiftwork group, regardless of the working patterns, the BMI and % body fat of the group that ate more than three times a day were significantly lower than those of the group that ate less than twice a day. The results of the present study suggest that it is difficult to ensure the time and opportunity for meals for shift workers. We consider that it is necessary to prevent them skipping of meals, and to support a proper dietary intake during the night.

  16. Emergency Radiology Practice Patterns: Shifts, Schedules, and Job Satisfaction.

    PubMed

    Hanna, Tarek N; Shekhani, Haris; Lamoureux, Christine; Mar, Hanna; Nicola, Refky; Sliker, Clint; Johnson, Jamlik-Omari

    2017-03-01

    To assess the practice environment of emergency radiologists with a focus on schedule, job satisfaction, and self-perception of health, wellness, and diagnostic accuracy. A survey drawing from prior radiology and health care shift-work literature was distributed via e-mail to national societies, teleradiology groups, and private practices. The survey remained open for 4 weeks in 2016, with one reminder. Data were analyzed using hypothesis testing and logistic regression modeling. Response rate was 29.6% (327/1106); 69.1% of respondents (n = 226) were greater than 40 years old, 73% (n = 240) were male, and 87% (n = 284) practiced full time. With regard to annual overnight shifts (NS): 36% (n = 118) did none, 24.9% (n = 81) did 182 or more, and 15.6% (n = 51) did 119. There was a significant association between average NS worked per year and both perceived negative health effects (P < .01) and negative impact on memory (P < .01). There was an inverse association between overall job enjoyment and number of annual NS (P < .05). The odds of agreeing to the statement "I enjoy my job" for radiologists who work no NS is 2.21 times greater than for radiologists who work at least 119 NS, when shift length is held constant. Radiologists with 11+ years of experience who work no NS or 1 to 100 NS annually have lower odds of feeling overwhelmed when compared with those working the same number of NS with <10 years' experience. There is significant variation in emergency radiology practice patterns. Annual NS burden is associated with lower job satisfaction and negative health self-perception. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  17. Working and caring for a child with chronic illness: A review of current literature.

    PubMed

    Kish, A M; Newcombe, P A; Haslam, D M

    2018-05-01

    Advances in medical knowledge have contributed to the increase in the number of children living with some form of long-term chronic illness or condition. As a consequence of these advancements, treatments that are more accessible and easier to administer, usually within a child's home, have been developed. However, this may mean that parents take on greater treatment responsibility and require extra time and energy to meet these tasks, additional to other responsibilities. This review paper aims to summarize and critique existing literature on working parents of children with a chronic condition, by focusing on patterns of parent work, the challenges experienced, and the flow-on consequences to well-being. Employing a narrative, meta-synthesis of the current literature, this review identified 3 key themes related to working parents of children with chronic illness. The paper first identifies that although employment is less common, these parents are not necessarily nonworking. Second, these parents experience numerous challenges including balancing work and family, time constraints, stress, and feelings of "doing it all." And third, the above challenges lead to additional impacts on parental quality of life. This review summarizes what is currently known about work patterns, challenges, and consequences in parents of children with chronic conditions. Employment is clearly impacted for these parents. Although workplace challenges have been extensively researched, other challenges (eg, personal and family) and impacts on their well-being have not. This review discusses the present standing of this research. It outlines the strengths and limitations of the current literature, makes recommendations for future research, and suggests theoretical and practical implications of the further findings. © 2018 John Wiley & Sons Ltd.

  18. Modelling fatigue and the use of fatigue models in work settings.

    PubMed

    Dawson, Drew; Ian Noy, Y; Härmä, Mikko; Akerstedt, Torbjorn; Belenky, Gregory

    2011-03-01

    In recent years, theoretical models of the sleep and circadian system developed in laboratory settings have been adapted to predict fatigue and, by inference, performance. This is typically done using the timing of prior sleep and waking or working hours as the primary input and the time course of the predicted variables as the primary output. The aim of these models is to provide employers, unions and regulators with quantitative information on the likely average level of fatigue, or risk, associated with a given pattern of work and sleep with the goal of better managing the risk of fatigue-related errors and accidents/incidents. The first part of this review summarises the variables known to influence workplace fatigue and draws attention to the considerable variability attributable to individual and task variables not included in current models. The second part reviews the current fatigue models described in the scientific and technical literature and classifies them according to whether they predict fatigue directly by using the timing of prior sleep and wake (one-step models) or indirectly by using work schedules to infer an average sleep-wake pattern that is then used to predict fatigue (two-step models). The third part of the review looks at the current use of fatigue models in field settings by organizations and regulators. Given their limitations it is suggested that the current generation of models may be appropriate for use as one element in a fatigue risk management system. The final section of the review looks at the future of these models and recommends a standardised approach for their use as an element of the 'defenses-in-depth' approach to fatigue risk management. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Sleep Patterns and Fatigue in New Mothers and Fathers

    PubMed Central

    Gay, Caryl L.; Lee, Kathryn A.; Lee, Shih-Yu

    2005-01-01

    The purpose of this study was to describe the sleep patterns and fatigue of both mothers and fathers before and after childbirth. The authors used wrist actigraphy and questionnaires to estimate sleep and fatigue in 72 couples during their last month of pregnancy and 1st month postpartum. Both parents experienced more sleep disruption at night during the postpartum period as compared to the last month of pregnancy. Compared to fathers, with their stable 24-h sleep patterns over time, mothers had less sleep at night and more sleep during the day after the baby was born. Sleep patterns were also related to parents’work status and type of infant feeding. Both parents self-reported more sleep disturbance and fatigue during the 1st month postpartum than during pregnancy. Mothers reported more sleep disturbance than fathers, but there was no gender difference in ratings of fatigue. At both time points, fathers obtained less total sleep than mothers when sleep was objectively measured throughout the entire 24-h day. Further research is needed to determine the duration of sleep loss for both mothers and fathers, to evaluate the effect of disrupted sleep and sleep loss on psychosocial functioning and job performance, and to develop interventions for improving sleep patterns of new parents. PMID:15068660

  20. CO2 time series patterns in contrasting headwater streams of North America

    USGS Publications Warehouse

    Crawford, John T.; Stanley, Emily H.; Dornblaser, Mark M.; Striegl, Robert G.

    2017-01-01

    We explored the underlying patterns of temporal stream CO2 partial pressure (pCO2) variability using highfrequency sensors in seven disparate headwater streams distributed across the northern hemisphere. We also compared this dataset of [40,000 pCO2 records with other published records from lotic systems. Individual stream sites exhibited relatively distinct pCO2 patterns over time with few consistent traits across sites. Some sites showed strong diel variability, some exhibited increasing pCO2 with increasing discharge, whereas other streams had reduced pCO2 with increasing discharge or no clear response to changes in flow. The only ‘‘universal’’ signature observed in headwater streams was a late summer pCO2 maxima that was likely driven by greatest rates of organic matter respiration due to highest annual temperatures. However, we did not observe this seasonal pattern in a southern hardwood forest site, likely because the region was transitioning from a severe drought. This work clearly illustrates the heterogeneous nature of headwater streams, and highlights the idiosyncratic nature of a non-conservative solute that is jointly influenced by physics, hydrology, and biology. We suggest that future researchers carefully select sensor locations (within and among streams) and provide additional contextual information when attempting to explain pCO2 patterns.

  1. Early work patterns for gynaecological cancer survivors in the USA.

    PubMed

    Nachreiner, N M; Ghebre, R G; Virnig, B A; Shanley, R

    2012-01-01

    Little is known about the balance between work demands and treatment plans for >4.3 million working-age cancer survivors in the USA. To describe changes in work status for gynaecological cancer survivors during the first 6 months following diagnosis and their experience with their employers' programmes and policies. One hundred and ten gynaecological cancer survivors who were working at the time of their cancer diagnosis completed a survey. Case record reviews documented their clinical characteristics and treatment details. Ninety-five women (86%) had surgery; 81 (74%) received chemotherapy, radiotherapy or both in addition to surgery. Nine per cent of women said that they changed their treatment plan because of their jobs; in contrast, 62% of women said that they changed their work situation to accommodate their treatment plan. Overall, the most common month for women to stop working was Month 1 (41%), to decrease hours was Month 2 (32%) and to increase hours was Month 6 (8%). Twenty-eight per cent of women were aware of employer policies that assisted the return to work process; 70% of women were familiar with the Family and Medical Leave Act (FMLA) and 56% with the Americans with Disabilities Act (ADA). Only 26% completed a formal request for work accommodations. After 6 months, 56 of 83 women (67%) remained working or had returned to work. Work patterns varied for these gynaecological cancer survivors over the first 6 months following diagnosis. Opportunities exist to improve communication about work and treatment expectations between cancer survivors, occupational health professionals, employers and treating clinicians.

  2. 76 FR 35801 - Examinations of Work Areas in Underground Coal Mines and Pattern of Violations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-20

    ..., 1219-AB73 Examinations of Work Areas in Underground Coal Mines and Pattern of Violations AGENCY: Mine... public hearings on the Agency's proposed rules for Examinations of Work Areas in Underground Coal Mines... Underground Coal Mines' submissions, and with ``RIN 1219-AB73'' for Pattern of Violations' submissions...

  3. Lifetime Achievement Patterns, Retirement and Life Satisfaction of Gifted Aged Women.

    ERIC Educational Resources Information Center

    Holahan, Carole Kovalic

    1981-01-01

    Investigated the relationship of lifetime achievement patterns and retirement, to life satisfaction for gifted aging women (N=352). Results showed a significant interaction between marital status and work pattern on overall life satisfaction suggesting an additive negative effect of loss of spouse and a work history of working for income alone.…

  4. Application of a VLSI vector quantization processor to real-time speech coding

    NASA Technical Reports Server (NTRS)

    Davidson, G.; Gersho, A.

    1986-01-01

    Attention is given to a working vector quantization processor for speech coding that is based on a first-generation VLSI chip which efficiently performs the pattern-matching operation needed for the codebook search process (CPS). Using this chip, the CPS architecture has been successfully incorporated into a compact, single-board Vector PCM implementation operating at 7-18 kbits/sec. A real time Adaptive Vector Predictive Coder system using the CPS has also been implemented.

  5. Management, Governance and Leadership: A Guide for College and University Administrators.

    ERIC Educational Resources Information Center

    Millett, John D.

    Perspectives on management, governance, and leadership of the university are presented. The following organizational characteristics are discussed: sense of purpose, work specialization, work technology, pattern of cooperation, pattern of management, pattern of governance, and pattern of leadership. The following purposes of American colleges and…

  6. Patterns of activity and use of time in rural Bangladesh: class, gender, and seasonal variations.

    PubMed

    Zaman, H

    1995-04-01

    Tarapur is a village in the district of Rajshahi, Bangladesh, covering an area of 821.05 acres. 342 households with a total population of 1981 were identified in the village by the 1985 census. The author investigated the use of time during 1984 and 1985 in busy, intermediate, and slack seasons among the village population to examine the variation in time use by gender and social class. Activity patterns were found to vary from one season to another, and also across social classes. The study highlights the need to refine some of the conceptual and methodological issues in the collection of data on women and work. The study also presents useful data on home-based production and market-oriented work. It could be useful to adopt an anthropological approach in order to understand the allocation of time by men and women from the perspective of household production and the local economy and culture. Study findings focus upon the following policy issues: the need for a better understanding and recognition of the significant role of women in field agriculture and postharvest processing, creation of further nontraditional employment and business opportunities for poor women in rural areas, and consciousness-raising and the challenge of cultural barriers affecting women. Rural women, especially those in need of employment and involved in market-oriented production, should be the target of mainstream development activities in future planning.

  7. Influence of moderate training on gait and work capacity of fibromyalgia patients: a preliminary field study.

    PubMed

    Tiidus, Peter M; Pierrynowski, Michael; Dawson, Kimberley A

    2002-12-01

    This field study examined the influence of moderate intensity training on gait patterns and work capacity of individuals with fibromyalgia syndrome (FS). FS is a chronic condition of unknown etiology, characterized by muscle tenderness, pain and stiffness and often accompanied by depression and fatigue which seems to occur primarily in middle aged females. There is no known cure for FS but treatment often includes a prescription of mild exercise. Few studies have evaluated the effectiveness of mild exercise on work capacity and gait patterns in FS patients. Participants were 14 females (age 47.0 ± 7.6 y) who participated in a 10 wk community based aerobic, strength and stretching program designed for FS individuals. Subjects were evaluated pre- and post-program and at a 2 month follow up. Work capacity was estimated by a sub-maximal PWC 170 cycle ergometer test and a Borg perceived exertion scale. Gait was assessed using OptoTrack three dimensional kinematics with 16 channel analogue data acquisition system. Trunk flexibility was also assessed. No significant change in estimated work capacity or flexibility was seen between pre- post- and follow up times. Nevertheless, a significant increase in self selected walking speed (p < 0.05) and a trend toward a more normal gait pattern that was sustained in the follow up testing was noted. We had previously also reported a significant improvement in muscle pain and other fibromyalgia symptoms in this population consequent to the training program. It was concluded that mild exercise training that does not influence work capacity or trunk flexibility can nevertheless positively influence gait mechanics and fibromyalgia symptoms in female FS patients.

  8. Influence of Moderate Training on Gait and Work Capacity of Fibromyalgia Patients: A Preliminary Field Study

    PubMed Central

    Tiidus, Peter M.; Pierrynowski, Michael; Dawson, Kimberley A.

    2002-01-01

    This field study examined the influence of moderate intensity training on gait patterns and work capacity of individuals with fibromyalgia syndrome (FS). FS is a chronic condition of unknown etiology, characterized by muscle tenderness, pain and stiffness and often accompanied by depression and fatigue which seems to occur primarily in middle aged females. There is no known cure for FS but treatment often includes a prescription of mild exercise. Few studies have evaluated the effectiveness of mild exercise on work capacity and gait patterns in FS patients. Participants were 14 females (age 47.0 ± 7.6 y) who participated in a 10 wk community based aerobic, strength and stretching program designed for FS individuals. Subjects were evaluated pre- and post-program and at a 2 month follow up. Work capacity was estimated by a sub-maximal PWC 170 cycle ergometer test and a Borg perceived exertion scale. Gait was assessed using OptoTrack three dimensional kinematics with 16 channel analogue data acquisition system. Trunk flexibility was also assessed. No significant change in estimated work capacity or flexibility was seen between pre- post- and follow up times. Nevertheless, a significant increase in self selected walking speed (p < 0.05) and a trend toward a more normal gait pattern that was sustained in the follow up testing was noted. We had previously also reported a significant improvement in muscle pain and other fibromyalgia symptoms in this population consequent to the training program. It was concluded that mild exercise training that does not influence work capacity or trunk flexibility can nevertheless positively influence gait mechanics and fibromyalgia symptoms in female FS patients. PMID:24748843

  9. Work step indication with grid-pattern projection for demented senior people.

    PubMed

    Uranishi, Yuki; Yamamoto, Goshiro; Asghar, Zeeshan; Pulli, Petri; Kato, Hirokazu; Oshiro, Osamu

    2013-01-01

    This paper proposes a work step indication method for supporting daily work with a grid-pattern projection. To support an independent life of demented senior people, it is desirable that an instruction is easy to understand visually and not complicated. The proposed method in this paper uses a range image sensor and a camera in addition to a projector. A 3D geometry of a target scene is measured by the range image sensor, and the grid-pattern is projected onto the scene directly. Direct projection of the work step is easier to be associated with the target objects around the assisted person, and the grid-pattern is a solution to indicate the spatial instruction. A prototype has been implemented and has demonstrated that the proposed grid-pattern projection is easy to show the work step.

  10. Influence of changing work patterns on training in anaesthesia: an analysis of activity in a UK teaching hospital from 1996 to 2004.

    PubMed

    Underwood, S M; McIndoe, A K

    2005-11-01

    We aimed to assess the influence of reduced working hours on training in a UK teaching hospital as the specialist registrar grade was introduced in 1996, the New Deal was implemented in 2001 and the Working Time Directive (WTD) took effect for doctors in training in 2004. We analysed data from operating theatres in our hospital looking at grade of anaesthetist, time of day, emergency category, and specialty for more than 50,000 cases. Although direct supervision of trainees increased from 32 to 37 to 47%, senior house officer (SHO) and specialist registrar (SpR) caseload reduced by 20 and 21%, respectively, while that of the consultants rose. The reduction in total operating theatre cases for our trainees was evident across the epochs analysed, case numbers fell after introduction of the New Deal as well as more recently following the WTD, particularly for SHOs who are now doing a larger proportion of their work at night. SHOs and SpRs are doing more obstetric cases than in previous times but these are regional and not general anaesthetics.

  11. Radiofrequency Identification

    PubMed Central

    Jones, Terry L.

    2017-01-01

    A national campaign is underway to increase the amount of time staff nurses spend at the bedside of hospitalized patients through redesign of the work environment. This kind of work redesign requires robust data depicting what nurses do and how they spend their time. Historically, these kinds of data have been difficult, costly, and time consuming to collect. Wireless capture of data on the movement of humans within the work environment (ie, time and motion) is now possible through radiofrequency identification technology. When small tracking devices the size of a quarter are affixed to their clothing, the movement of nurses throughout a patient care unit can be monitored. The duration and frequency of patient interaction are captured along with the duration of time spent in other locations of interest to include nurses’ station, supply room, medication room, doctors’ station, electronic documentation stations, family waiting rooms, and the hallway. Patterns of nurse movement and time allocation can be efficiently identified, and the effects of staffing practices, workflows, and unit layout evaluated. Integration of radiofrequency identification time and motion data with other databases enables nurse leaders to link nursing time to important cost and quality outcomes. Nurse leaders should explore the usefulness of radiofrequency identification technology in addressing data needs for nurse time and motion. PMID:22592451

  12. Food reward without a timing component does not alter the timing of activity under positive energy balance.

    PubMed

    van der Vinne, V; Akkerman, J; Lanting, G D; Riede, S J; Hut, R A

    2015-09-24

    Circadian clocks drive daily rhythms in physiology and behavior which allow organisms to anticipate predictable daily changes in the environment. In most mammals, circadian rhythms result in nocturnal activity patterns although plasticity of the circadian system allows activity patterns to shift to different times of day. Such plasticity is seen when food access is restricted to a few hours during the resting (light) phase resulting in food anticipatory activity (FAA) in the hours preceding food availability. The mechanisms underlying FAA are unknown but data suggest the involvement of the reward system and homeostatic regulation of metabolism. We previously demonstrated the isolated effect of metabolism by inducing diurnality in response to energetic challenges. Here the importance of reward timing in inducing daytime activity is assessed. The daily activity distribution of mice earning palatable chocolate at their preferred time by working in a running wheel was compared with that of mice receiving a timed palatable meal at noon. Mice working for chocolate (WFC) without being energetically challenged increased their total daily activity but this did not result in a shift to diurnality. Providing a chocolate meal at noon each day increased daytime activity, identifying food timing as a factor capable of altering the daily distribution of activity and rest. These results show that timing of food reward and energetic challenges are both independently sufficient to induce diurnality in nocturnal mammals. FAA observed following timed food restriction is likely the result of an additive effect of distinct regulatory pathways activated by energetic challenges and food reward. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  13. Stability and Hopf bifurcation in a simplified BAM neural network with two time delays.

    PubMed

    Cao, Jinde; Xiao, Min

    2007-03-01

    Various local periodic solutions may represent different classes of storage patterns or memory patterns, and arise from the different equilibrium points of neural networks (NNs) by applying Hopf bifurcation technique. In this paper, a bidirectional associative memory NN with four neurons and multiple delays is considered. By applying the normal form theory and the center manifold theorem, analysis of its linear stability and Hopf bifurcation is performed. An algorithm is worked out for determining the direction and stability of the bifurcated periodic solutions. Numerical simulation results supporting the theoretical analysis are also given.

  14. Online Activity Levels Are Related to Caffeine Dependency.

    PubMed

    Phillips, James G; Landhuis, C Erik; Shepherd, Daniel; Ogeil, Rowan P

    2016-05-01

    Online activity could serve in the future as behavioral markers of emotional states for computer systems (i.e., affective computing). Hence, this study considered relationships between self-reported stimulant use and online study patterns. Sixty-two undergraduate psychology students estimated their daily caffeine use, and this was related to study patterns as tracked by their use of a Learning Management System (Blackboard). Caffeine dependency was associated with less time spent online, lower rates of file access, and fewer online activities completed. Reduced breadth or depth of processing during work/study could be used as a behavioral marker of stimulant use.

  15. Enabling the First Ever Measurement of Coherent Neutrino Scattering Through Background Neutron Measurements.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reyna, David; Betty, Rita

    Using High Performance Computing to Examine the Processes of Neurogenesis Underlying Pattern Separation/Completion of Episodic Information - Sandia researchers developed novel methods and metrics for studying the computational function of neurogenesis,thus generating substantial impact to the neuroscience and neural computing communities. This work could benefit applications in machine learning and other analysis activities. The purpose of this project was to computationally model the impact of neural population dynamics within the neurobiological memory system in order to examine how subareas in the brain enable pattern separation and completion of information in memory across time as associated experiences.

  16. Matrices pattern using FIB; 'Out-of-the-box' way of thinking.

    PubMed

    Fleger, Y; Gotlib-Vainshtein, K; Talyosef, Y

    2017-03-01

    Focused ion beam (FIB) is an extremely valuable tool in nanopatterning and nanofabrication for potentially high-resolution patterning, especially when refers to He ion beam microscopy. The work presented here demonstrates an 'out-of-the-box' method of writing using FIB, which enables creating very large matrices, up to the beam-shift limitation, in short times and with high accuracy unachievable by any other writing technique. The new method allows combining different shapes in nanometric dimensions and high resolutions for wide ranges. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  17. On Using the Weimer Statistical Model for Real-Time Ionospheric Specifications and Forecasts

    NASA Astrophysics Data System (ADS)

    Bekerat, H. A.; Schunk, R. W.; Scherliess, L.

    2002-12-01

    The Weimer statistical model (Weimer, 2001) for the high-latitude convection pattern was tested with regard to its ability to produce real-time convection patterns. This work is being conducted under the polar section of GAIM (Global Assimilation of Ionospheric Measurements). The method adopted involves the comparison of the cross-track ion drift velocities measured by DMSP satellites with those calculated from the Weimer model. Starting with a Weimer pattern obtained using real-time IMF and solar wind data at the time of a DMSP satellite pass in the high-latitude ionosphere, the cross-track ion drift velocities along the DMSP track were calculated from the Weimer convection model and compared to those measured by the DMSP satellite. Then, in order to improve the agreement between the measurement and the model, two of the input parameters to the model, the IMF clock-angle and the solar wind speed, were varied to get the pattern that gives the best agreement with the DMSP satellite measurements. Four months of data (March, July, September, and December 1998) were used to test the Weimer model. The result shows that the agreement between the measurement and the Weimer model is improved by using this procedure. The Weimer model is good in a statistical sense, it was able to produce the large-scale structure in most cases. However, it is not good enough to be used for real-time ionospheric specifications and forecasts because it failed to produce a lot of the mesoscale structure measured along most DMSP satellite passes. Reference Weimer, D. R., J. Geophys. Res., 106, 407,2001

  18. Discovering significant evolution patterns from satellite image time series.

    PubMed

    Petitjean, François; Masseglia, Florent; Gançarski, Pierre; Forestier, Germain

    2011-12-01

    Satellite Image Time Series (SITS) provide us with precious information on land cover evolution. By studying these series of images we can both understand the changes of specific areas and discover global phenomena that spread over larger areas. Changes that can occur throughout the sensing time can spread over very long periods and may have different start time and end time depending on the location, which complicates the mining and the analysis of series of images. This work focuses on frequent sequential pattern mining (FSPM) methods, since this family of methods fits the above-mentioned issues. This family of methods consists of finding the most frequent evolution behaviors, and is actually able to extract long-term changes as well as short term ones, whenever the change may start and end. However, applying FSPM methods to SITS implies confronting two main challenges, related to the characteristics of SITS and the domain's constraints. First, satellite images associate multiple measures with a single pixel (the radiometric levels of different wavelengths corresponding to infra-red, red, etc.), which makes the search space multi-dimensional and thus requires specific mining algorithms. Furthermore, the non evolving regions, which are the vast majority and overwhelm the evolving ones, challenge the discovery of these patterns. We propose a SITS mining framework that enables discovery of these patterns despite these constraints and characteristics. Our proposal is inspired from FSPM and provides a relevant visualization principle. Experiments carried out on 35 images sensed over 20 years show the proposed approach makes it possible to extract relevant evolution behaviors.

  19. Integration of population mobility in the evaluation of air quality measures on local and regional scales

    NASA Astrophysics Data System (ADS)

    Dhondt, S.; Beckx, C.; Degraeuwe, B.; Lefebvre, W.; Kochan, B.; Bellemans, T.; Int Panis, L.; Macharis, C.; Putman, K.

    2012-11-01

    By focussing on air pollutant concentration levels only, the variation in population mobility is not taken into account when assessing the exposure. Transportation policies have an impact on both concentration levels and mobility patterns. The impact of a fuel price increase policy on population exposure to elemental carbon (EC) was evaluated and compared to the base scenario (current situation), taking into account time-activity patterns - including time in commute. We assessed the effect on exposure of both the change in concentrations and whereabouts. The decrease in exposure due to the fuel price increase using residential information only was limited to areas near highways and urban centres. Integrating population movement, exposures to EC were higher and the decrease in exposure was no longer limited to areas near traffic hotspots. For inhabitants of urban areas, the exposure integrating time-activity patterns was more similar to the residential exposure, as they spent more time in their own neighbourhood. For people living further away from traffic hotspots, the estimated impact of the policy was higher than expected for residential exposure. These people profited both from the higher decrease in concentrations at their work/shop/leisure destinations in more urban areas and, as they have to travel longer, also had a larger gain from the high decrease in concentrations during transport. Therefore, the impact of changing concentrations is underestimated when using residential exposure only. These results show the importance of taking into activity-travel patterns when planning future actions.

  20. Cost-effective, transfer-free, flexible resistive random access memory using laser-scribed reduced graphene oxide patterning technology.

    PubMed

    Tian, He; Chen, Hong-Yu; Ren, Tian-Ling; Li, Cheng; Xue, Qing-Tang; Mohammad, Mohammad Ali; Wu, Can; Yang, Yi; Wong, H-S Philip

    2014-06-11

    Laser scribing is an attractive reduced graphene oxide (rGO) growth and patterning technology because the process is low-cost, time-efficient, transfer-free, and flexible. Various laser-scribed rGO (LSG) components such as capacitors, gas sensors, and strain sensors have been demonstrated. However, obstacles remain toward practical application of the technology where all the components of a system are fabricated using laser scribing. Memory components, if developed, will substantially broaden the application space of low-cost, flexible electronic systems. For the first time, a low-cost approach to fabricate resistive random access memory (ReRAM) using laser-scribed rGO as the bottom electrode is experimentally demonstrated. The one-step laser scribing technology allows transfer-free rGO synthesis directly on flexible substrates or non-flat substrates. Using this time-efficient laser-scribing technology, the patterning of a memory-array area up to 100 cm(2) can be completed in 25 min. Without requiring the photoresist coating for lithography, the surface of patterned rGO remains as clean as its pristine state. Ag/HfOx/LSG ReRAM using laser-scribing technology is fabricated in this work. Comprehensive electrical characteristics are presented including forming-free behavior, stable switching, reasonable reliability performance and potential for 2-bit storage per memory cell. The results suggest that laser-scribing technology can potentially produce more cost-effective and time-effective rGO-based circuits and systems for practical applications.

  1. Depletion force induced collective motion of microtubules driven by kinesin

    NASA Astrophysics Data System (ADS)

    Inoue, Daisuke; Mahmot, Bulbul; Kabir, Arif Md. Rashedul; Farhana, Tamanna Ishrat; Tokuraku, Kiyotaka; Sada, Kazuki; Konagaya, Akihiko; Kakugo, Akira

    2015-10-01

    Collective motion is a fascinating example of coordinated behavior of self-propelled objects, which is often associated with the formation of large scale patterns. Nowadays, the in vitro gliding assay is being considered a model system to experimentally investigate various aspects of group behavior and pattern formation by self-propelled objects. In the in vitro gliding assay, cytoskeletal filaments F-actin or microtubules are driven by the surface immobilized associated biomolecular motors myosin or dynein respectively. Although the F-actin/myosin or microtubule/dynein system was found to be promising in understanding the collective motion and pattern formation by self-propelled objects, the most widely used biomolecular motor system microtubule/kinesin could not be successfully employed so far in this regard. Failure in exhibiting collective motion by kinesin driven microtubules is attributed to the intrinsic properties of kinesin, which was speculated to affect the behavior of individual gliding microtubules and mutual interactions among them. In this work, for the first time, we have demonstrated the collective motion of kinesin driven microtubules by regulating the mutual interaction among the gliding microtubules, by employing a depletion force among them. Proper regulation of the mutual interaction among the gliding microtubules through the employment of the depletion force was found to allow the exhibition of collective motion and stream pattern formation by the microtubules. This work offers a universal means for demonstrating the collective motion using the in vitro gliding assay of biomolecular motor systems and will help obtain a meticulous understanding of the fascinating coordinated behavior and pattern formation by self-propelled objects.Collective motion is a fascinating example of coordinated behavior of self-propelled objects, which is often associated with the formation of large scale patterns. Nowadays, the in vitro gliding assay is being considered a model system to experimentally investigate various aspects of group behavior and pattern formation by self-propelled objects. In the in vitro gliding assay, cytoskeletal filaments F-actin or microtubules are driven by the surface immobilized associated biomolecular motors myosin or dynein respectively. Although the F-actin/myosin or microtubule/dynein system was found to be promising in understanding the collective motion and pattern formation by self-propelled objects, the most widely used biomolecular motor system microtubule/kinesin could not be successfully employed so far in this regard. Failure in exhibiting collective motion by kinesin driven microtubules is attributed to the intrinsic properties of kinesin, which was speculated to affect the behavior of individual gliding microtubules and mutual interactions among them. In this work, for the first time, we have demonstrated the collective motion of kinesin driven microtubules by regulating the mutual interaction among the gliding microtubules, by employing a depletion force among them. Proper regulation of the mutual interaction among the gliding microtubules through the employment of the depletion force was found to allow the exhibition of collective motion and stream pattern formation by the microtubules. This work offers a universal means for demonstrating the collective motion using the in vitro gliding assay of biomolecular motor systems and will help obtain a meticulous understanding of the fascinating coordinated behavior and pattern formation by self-propelled objects. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr02213d

  2. 3D Tracking via Shoe Sensing.

    PubMed

    Li, Fangmin; Liu, Guo; Liu, Jian; Chen, Xiaochuang; Ma, Xiaolin

    2016-10-28

    Most location-based services are based on a global positioning system (GPS), which only works well in outdoor environments. Compared to outdoor environments, indoor localization has created more buzz in recent years as people spent most of their time indoors working at offices and shopping at malls, etc. Existing solutions mainly rely on inertial sensors (i.e., accelerometer and gyroscope) embedded in mobile devices, which are usually not accurate enough to be useful due to the mobile devices' random movements while people are walking. In this paper, we propose the use of shoe sensing (i.e., sensors attached to shoes) to achieve 3D indoor positioning. Specifically, a short-time energy-based approach is used to extract the gait pattern. Moreover, in order to improve the accuracy of vertical distance estimation while the person is climbing upstairs, a state classification is designed to distinguish the walking status including plane motion (i.e., normal walking and jogging horizontally), walking upstairs, and walking downstairs. Furthermore, we also provide a mechanism to reduce the vertical distance accumulation error. Experimental results show that we can achieve nearly 100% accuracy when extracting gait patterns from walking/jogging with a low-cost shoe sensor, and can also achieve 3D indoor real-time positioning with high accuracy.

  3. Rolling up of Large-scale Laminar Vortex Ring from Synthetic Jet Impinging onto a Wall

    NASA Astrophysics Data System (ADS)

    Xu, Yang; Pan, Chong; Wang, Jinjun; Flow Control Lab Team

    2015-11-01

    Vortex ring impinging onto a wall exhibits a wide range of interesting behaviors. The present work devotes to an experimental investigation of a series of small-scale vortex rings impinging onto a wall. These laminar vortex rings were generated by a piston-cylinder driven synthetic jet in a water tank. Laser Induced Fluorescence (LIF) and Particle Image Velocimetry (PIV) were used for flow visualization/quantification. A special scenario of vortical dynamic was found for the first time: a large-scale laminar vortex ring is formed above the wall, on the outboard side of the jet. This large-scale structure is stable in topology pattern, and continuously grows in strength and size along time, thus dominating dynamics of near wall flow. To quantify its spatial/temporal characteristics, Finite-Time Lyapunov Exponent (FTLE) fields were calculated from PIV velocity fields. It is shown that the flow pattern revealed by FTLE fields is similar to the visualization. The size of this large-scale vortex ring can be up to one-order larger than the jet vortices, and its rolling-up speed and entrainment strength was correlated to constant vorticity flux issued from the jet. This work was supported by the National Natural Science Foundation of China (Grants No.11202015 and 11327202).

  4. Defect reduction of high-density full-field patterns in jet and flash imprint lithography

    NASA Astrophysics Data System (ADS)

    Singh, Lovejeet; Luo, Kang; Ye, Zhengmao; Xu, Frank; Haase, Gaddi; Curran, David; LaBrake, Dwayne; Resnick, Douglas; Sreenivasan, S. V.

    2011-04-01

    Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash Imprint Lithography (J-FIL) involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the fluid which then quickly flows into the relief patterns in the mask by capillary action. Following this filling step, the resist is crosslinked under UV radiation, and then the mask is removed leaving a patterned resist on the substrate. Acceptance of imprint lithography for manufacturing will require demonstration that it can attain defect levels commensurate with the defect specifications of high end memory devices. Typical defectivity targets are on the order of 0.10/cm2. This work summarizes the results of defect inspections focusing on two key defect types; random non-fill defects occurring during the resist filling process and repeater defects caused by interactions with particles on the substrate. Non-fill defectivity must always be considered within the context of process throughput. The key limiting throughput step in an imprint process is resist filling time. As a result, it is critical to characterize the filling process by measuring non-fill defectivity as a function of fill time. Repeater defects typically have two main sources; mask defects and particle related defects. Previous studies have indicated that soft particles tend to cause non-repeating defects. Hard particles, on the other hand, can cause either resist plugging or mask damage. In this work, an Imprio 500 twenty wafer per hour (wph) development tool was used to study both defect types. By carefully controlling the volume of inkjetted resist, optimizing the drop pattern and controlling the resist fluid front during spreading, fill times of 1.5 seconds were achieved with non-fill defect levels of approximately 1.2/cm2. Longevity runs were used to study repeater defects and a nickel contamination was identified as the key source of particle induced repeater defects.

  5. Associations between hours worked, symptoms and health resource utilization among full-time male Japanese workers.

    PubMed

    Sato, Keiko; Yamazaki, Shin; Hayashino, Yasuaki; Takegami, Misa; Tokuda, Yasuharu; Takahashi, Osamu; Shimbo, Takuro; Hinohara, Shigeaki; Fukui, Tsuguya; Fukuhara, Shunichi

    2011-01-01

    To investigate the association between hours worked, symptoms experienced, and health resource utilization. Data were collected from a nationally representative sample of households in Japan. We studied full-time male workers aged 18-65 yr who worked 100 h or more per month. First, we examined the association between hours worked and symptoms experienced. Second, we examined the association between hours worked and the type of health resource utilized, such as physician visits, over-the-counter (OTC) medication use, dietary supplement use, and complementary and alternative medicine (CAM) provider visits. We used a multivariable negative binominal model in each analysis. Of the 762 male workers, 598 reported experiencing symptoms at least once a month. We categorized participants based on the number of hours worked per month (h/mo): 100-200 h/mo, 201-250 h/mo, and over 250 h/mo. Compared with those working 201-250 h/mo, those working 100-200 h/mo had more frequent physician visits (rate ratio:1.67, 95% CI: 1.17 to 2.38) and those working over 250 h/mo had significantly lower rates of CAM provider visits and tended to use dietary supplements for symptoms. Participants who worked 201-250 h/mo used OTC medication most frequently. No significant association was observed between the number of hours worked and number of symptoms experienced. The more hours worked by full-time male workers, the more likely they were to use health resources that had a lower time requirement. Greater attention should be paid to patterns of health resource utilization among workers and their consequent influence on long-term health status.

  6. U.S. Department of Energy, Illness and Injury Surveillance Program, Worker Health Summary, 1995-2004

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    U.S. Department of Energy, Office of Health, Safety and Security, Office of Illness and Injury Prevention Programs

    The Department of Energy’s (DOE) Illness and Injury Surveillance Program has created an opportunity to assess illness and injury rates and patterns among workers at participating sites for well over a decade. The Worker Health Summary introduces an additional perspective on worker health with the introduction of analyses comparing the experience of sites in different program offices and a focus on time trends covering a decade of worker illness and injury experience. These analyses by program office suggest that illness and injury patterns among National Nuclear Security Administration (NNSA) workers diverge in many ways from those seen among Environmental Managementmore » (EM) and Science workers for reasons not yet understood. These differences will receive further investigation in future special focus studies, as will other findings of interest. With the time depth now available in our data, the Worker Health Summary reveals an additional nuance in worker health trends: changing health patterns in a specialized and skilled but aging work force. Older workers are becoming an increasing percentage of the work force, and their absence rates for diseases such as diabetes and hypertension are increasing as well. The impact of these emerging health issues, if properly addressed, can be managed to maintain or even enhance worker health and productivity. Prevention strategies designed to reduce the toll of these health conditions appear warranted, and this report gives us an indication of where to focus them. The analyses that follow reflect the Illness and Injury Surveillance Program’s continued commitment to apply a public health perspective in protecting the health of DOE’s work force.« less

  7. A longitudinal study of the relationship between work engagement and symptoms of anxiety and depression.

    PubMed

    Innstrand, Siw Tone; Langballe, Ellen Melbye; Falkum, Erik

    2012-02-01

    This longitudinal study examined the dynamic relationship between work engagement (vigour and dedication) and symptoms of anxiety and depression. A sample of 3475 respondents from eight different occupational groups (lawyers, physicians, nurses, teachers, church ministers, bus drivers, people working in advertising and people working in information technology) in Norway supplied data at two points in time with a 2-year time interval. The advantages of longitudinal design were utilized, including testing of reversed causation and controlling for unmeasured third variables. In general, the results showed that the hypothesized normal causal relationship was superior to a reversed causation model. In other words, this study supported the assumption that work engagement is more likely to be the antecedent for symptoms of depression and anxiety than the outcome. In particular, the vigour facet of work engagement provides lower levels of depression and anxiety 2 years later. However, additional analyses modelling unmeasured third variables indicate that unknown third variables may have created some spurious effects on the pattern of the observed relationship. Implications of the findings are discussed in the paper. Copyright © 2011 John Wiley & Sons, Ltd.

  8. Shift workers have similar leisure-time physical activity levels as day workers but are more sedentary at work.

    PubMed

    Hulsegge, Gerben; Gupta, Nidhi; Holtermann, Andreas; Jørgensen, Marie Birk; Proper, Karin I; van der Beek, Allard J

    2017-03-01

    Objective Physical inactivity has been hypothesized as an underlying factor for the association between shift work and adverse health outcomes. We compared leisure-time and occupational physical activity and sedentary behavior between day, night, and non-night shift workers. Methods We identified 612 day workers, 139 night shift workers and 61 non-night shift workers aged 18-65 years (54% men) in two Danish studies: the New method for Objective Measurements of physical Activity in Daily living (NOMAD) and the Danish Physical ACTivity cohort with Objective measurements (DPhacto) between 2011-2013. Sedentary behavior, light, and moderate-to-vigorous physical activity were measured using an accelerometer. Physical activity was expressed as percentage of leisure and work time spent in each activity. Linear regression analyses were used to test differences in physical activity and sedentary behavior between day, night, and non-night shift workers. Results No differences in leisure-time sedentary behavior and physical activity were observed between day and shift workers (P>0.05). Non-night shift workers spent 7.2% [95% confidence interval (95% CI) 2.3-12.1) more time in occupational sedentary behavior than day workers and 5.9% (95% CI -10.1- -1.7) and 1.9% (95% CI -3.7- -0.2) less time in occupational light and moderate-to-vigorous physical activity, respectively. Compared to day workers, night shift workers spent 4.3% (95% CI 2.4-6.1) more time at work in uninterrupted sedentary periods of ≥30 minutes. Conclusions Shift workers had similar leisure-time physical activity patterns as day workers, but were more sedentary at work. Future research should elucidate whether occupational physical inactivity and sedentary behavior contributes to shift work-related adverse health effects.

  9. A sequential coalescent algorithm for chromosomal inversions

    PubMed Central

    Peischl, S; Koch, E; Guerrero, R F; Kirkpatrick, M

    2013-01-01

    Chromosomal inversions are common in natural populations and are believed to be involved in many important evolutionary phenomena, including speciation, the evolution of sex chromosomes and local adaptation. While recent advances in sequencing and genotyping methods are leading to rapidly increasing amounts of genome-wide sequence data that reveal interesting patterns of genetic variation within inverted regions, efficient simulation methods to study these patterns are largely missing. In this work, we extend the sequential Markovian coalescent, an approximation to the coalescent with recombination, to include the effects of polymorphic inversions on patterns of recombination. Results show that our algorithm is fast, memory-efficient and accurate, making it feasible to simulate large inversions in large populations for the first time. The SMC algorithm enables studies of patterns of genetic variation (for example, linkage disequilibria) and tests of hypotheses (using simulation-based approaches) that were previously intractable. PMID:23632894

  10. Microenvironments engineered by inkjet bioprinting spatially direct adult stem cells toward muscle- and bone-like subpopulations.

    PubMed

    Phillippi, Julie A; Miller, Eric; Weiss, Lee; Huard, Johnny; Waggoner, Alan; Campbell, Phil

    2008-01-01

    In vivo, growth factors exist both as soluble and as solid-phase molecules, immobilized to cell surfaces and within the extracellular matrix. We used this rationale to develop more biologically relevant approaches to study stem cell behaviors. We engineered stem cell microenvironments using inkjet bioprinting technology to create spatially defined patterns of immobilized growth factors. Using this approach, we engineered cell fate toward the osteogenic lineage in register to printed patterns of bone morphogenetic protein (BMP) 2 contained within a population of primary muscle-derived stem cells (MDSCs) isolated from adult mice. This patterning approach was conducive to patterning the MDSCs into subpopulations of osteogenic or myogenic cells simultaneously on the same chip. When cells were cultured under myogenic conditions on BMP-2 patterns, cells on pattern differentiated toward the osteogenic lineage, whereas cells off pattern differentiated toward the myogenic lineage. Time-lapse microscopy was used to visualize the formation of multinucleated myotubes, and immunocytochemistry was used to demonstrate expression of myosin heavy chain (fast) in cells off BMP-2 pattern. This work provides proof-of-concept for engineering spatially controlled multilineage differentiation of stem cells using patterns of immobilized growth factors. This approach may be useful for understanding cell behaviors to immobilized biological patterns and could have potential applications for regenerative medicine.

  11. The improvement of GaN-based light-emitting diodes using nanopatterned sapphire substrate with small pattern spacing

    NASA Astrophysics Data System (ADS)

    Zhang, Yonghui; Wei, Tongbo; Wang, Junxi; Lan, Ding; Chen, Yu; Hu, Qiang; Lu, Hongxi; Li, Jinmin

    2014-02-01

    Self-assembly SiO2 nanosphere monolayer template is utilized to fabricate nanopatterned sapphire substrates (NPSSs) with 0-nm, 50-nm, and 120-nm spacing, receptively. The GaN growth on top of NPSS with 0-nm spacing has the best crystal quality because of laterally epitaxial overgrowth. However, GaN growth from pattern top is more difficult to get smooth surface than from pattern bottom. The rougher surface may result in a higher work voltage. The stimulation results of finite-difference time-domain (FDTD) display that too large or too small spacing lead to the reduced light extracted efficiency (LEE) of LEDs. Under a driving current 350 mA, the external quantum efficiencies (EQE) of GaN-based LEDs grown on NPSSs with 0-nm, 50-nm, and 120-nm spacing increase by 43.3%, 50.6%, and 39.1%, respectively, compared to that on flat sapphire substrate (FSS). The optimized pattern spacing is 50 nm for the NPSS with 600-nm pattern period.

  12. Some Things Never Change: Gender Segregation in Higher Education across Eight Nations and Three Decades

    ERIC Educational Resources Information Center

    Barone, Carlo

    2011-01-01

    This article examines the overall strength, the qualitative pattern, and the evolution over time of gender segregation in higher education across eight European countries. Although previous studies have focused primarily on the divide between humanistic and scientific fields, this work indicates that this divide accounts for no more than half of…

  13. Hippocampus and Medial Prefrontal Cortex Contributions to Trace and Contextual Fear Memory Expression over Time

    ERIC Educational Resources Information Center

    Beeman, Christopher L.; Bauer, Philip S.; Pierson, Jamie L.; Quinn, Jennifer J.

    2013-01-01

    Previous work has shown that damage to the dorsal hippocampus (DH) occurring at recent, but not remote, timepoints following acquisition produces a deficit in trace conditioned fear memory expression. The opposite pattern has been observed with lesions to the medial prefrontal cortex (mPFC). The present studies address: (1) whether these lesion…

  14. Parenting in the '80s. . . Student Guide. Brookhaven College Child Development Program.

    ERIC Educational Resources Information Center

    Linn, Hilda; And Others

    This guide was developed to accompany a series of 16 seminars on parenting offered by the Brookhaven College Child Development Program to help meet the concerns and needs of working parents in a time of changing lifestyles and family patterns. In addition to providing an overview of each seminar topic, the guide contains informational essays…

  15. Covering #SAE: A Mobile Reporting Class's Changing Patterns of Interaction on Twitter over Time

    ERIC Educational Resources Information Center

    Jones, Julie

    2015-01-01

    This study examined the social network that emerged on Twitter surrounding a mobile reporting class as they covered a national breaking news event. The work introduces pedagogical strategies that enhance students' learning opportunities. Through NodeXL and social network cluster analysis, six groups emerged from the Twitter interactions tied to…

  16. Background for Community-Level Work on Physical Health and Safety in Adolescence: Reviewing the Literature on Contributing Factors.

    ERIC Educational Resources Information Center

    Hatcher, Juliet L.; Scarpa, Juliet

    Although adolescence is characterized by general good health, this developmental stage is a key time for promoting a healthy lifestyle and preventing health-compromising behaviors and injuries. This paper presents a selective review of research into factors predicting health and safety behavior patterns and injury occurrence, focusing on…

  17. Alcohol and Other Drug Use among College Students in New York State: Findings From a Statewide College Survey (1996).

    ERIC Educational Resources Information Center

    Lucey, Richard, Jr.; Marel, Rozanne; Smith, R. B.; Frank, Blanche; Schmeidler, James

    This survey examined alcohol and other drug use among full- and part-time undergraduate students from 18 colleges in New York State. Students (n=4,646) completed questionnaires on demographics; working and living arrangements; academics; perceptions of campus substance abuse policies; drinking behavior and substance abuse patterns; and…

  18. NRH Neuroscience Research Center

    DTIC Science & Technology

    2005-06-01

    Gait Educationtf E Advanced gait 20-Patient * Community mobility Patient Assessmentt 21-Family/ caregiver ~( Formal assessment) 22-Staff Home Evaluation...interventions used. client diagnostic groups, which are termed practice patterns. Time for formal assessments, home evaluation, and work site The practice...18. Visual training 19. Sensory training Gait Education Interventions: 20. Patient 21. Family/ Caregiver Advanced Gait 22. Staff 23. Prescription

  19. Imagined and Emerging Career Patterns: Perceptions of Doctoral Students and Research Staff

    ERIC Educational Resources Information Center

    McAlpine, Lynn; Turner, Gill

    2012-01-01

    Increasingly, research staff positions rather than lectureships are the reality for social sciences PhD graduates wishing academic work. Within this context, our longitudinal study examined how social science doctoral students and research staff in two UK universities imagined their futures in and out of academia. The variation over time in how…

  20. Masked Symptoms: Mid-Life Women, Health, and Work

    ERIC Educational Resources Information Center

    Abramson, Zelda

    2007-01-01

    Data from the Canadian Labour Force Survey (1997) reveal that relatively few mid-life women offer ill health as a reason for leaving their job or downshifting to part-time employment, implying that the role of ill health may be inconsequential in effecting changing patterns in mid-life women's labour force activity. In contrast, interviews with 30…

  1. Timing Is Everything: Temporal Variation and Measures of School Quality. WCER Working Paper No. 2015-4

    ERIC Educational Resources Information Center

    Goff, Peter T.; Kam, Jihye; Kraszewski, Jacek

    2015-01-01

    Survey tools are used in education to direct policy, drive leadership decisions, and inform research. Increasingly survey measures of school climate and perspectives of leadership are incorporated into measures of school and principal quality. This study examines the role of temporal variations in survey response patterns using the data from the…

  2. Sheep laterality.

    PubMed

    Anderson, Dean M; Murray, Leigh W

    2013-01-01

    Turning preferences among 309 white-faced ewes were individually evaluated in an enclosed, artificially lit T-maze, followed by each ewe choosing either a right or left return alley to return to peers. Data recorded included time in the start box, time in the T-maze, exit arm chosen to leave the T-maze, and return alley. Right and left arms of the T-maze were chosen 65.7% and 34.3% of the time, respectively, while right and left return alleys were chosen 32.4% and 67.6%, respectively. Exit arm and return alley were not independently chosen (p <.0001), with observed counts being higher than expected under independence when ewes made the same choice for exit and alley (RR or LL turn patterns) and being lower than expected for alternating choices (RL or LR). Out of the 309 ewes, 28.2% and 30.1% chose RR and LL turn patterns, respectively, while 37.5% chose the RL turn pattern, but only 13 (4.2%) chose the LR turning pattern. Overall, ewes that initially turned right when presented a second turning opportunity had a slight preference to alternate their turning direction, while ewes that initially turned left tended to continue turning left when given another chance to turn. Exit arm and return alley laterality was not related (α =.05) to time of day the test was administered, ewe's age or genetics, most recent liveweight, or most recent shorn fleece weight. The mean time spent in the start box (21 s) was not related to exit arm (p =.947) or return alley (p =.779). Mean time (15 s) spent in the T-maze was not related to exit arm (p =.086) or return alley (p =.952). More research will be required to understand sheep turning laterality and how it can impact working facilities and research equipment.

  3. Spatiotemporal modelling and mapping of the bubonic plague epidemic in India.

    PubMed

    Yu, Hwa-Lung; Christakos, George

    2006-03-17

    This work studies the spatiotemporal evolution of bubonic plague in India during 1896-1906 using stochastic concepts and geographical information science techniques. In the past, most investigations focused on selected cities to conduct different kinds of studies, such as the ecology of rats. No detailed maps existed incorporating the space-time dependence structure and uncertainty sources of the epidemic system and providing a composite space-time picture of the disease propagation characteristics. Informative spatiotemporal maps were generated that represented mortality rates and geographical spread of the disease, and epidemic indicator plots were derived that offered meaningful characterizations of the spatiotemporal disease distribution. The bubonic plague in India exhibited strong seasonal and geographical features. During its entire duration, the plague continued to invade new geographical areas, while it followed a re-emergence pattern at many localities; its rate changed significantly during each year and the mortality distribution exhibited space-time heterogeneous patterns; prevalence usually occurred in the autumn and spring, whereas the plague stopped moving towards new locations during the summers. Modern stochastic modelling and geographical information science provide powerful means to study the spatiotemporal distribution of the bubonic plague epidemic under conditions of uncertainty and multi-sourced databases; to account for various forms of interdisciplinary knowledge; and to generate informative space-time maps of mortality rates and propagation patterns. To the best of our knowledge, this kind of plague maps and plots become available for the first time, thus providing novel perspectives concerning the distribution and space-time propagation of the deadly epidemic. Furthermore, systematic maps and indicator plots make possible the comparison of the spatial-temporal propagation patterns of different diseases.

  4. Spatiotemporal modelling and mapping of the bubonic plague epidemic in India

    PubMed Central

    Yu, Hwa-Lung; Christakos, George

    2006-01-01

    Background This work studies the spatiotemporal evolution of bubonic plague in India during 1896–1906 using stochastic concepts and geographical information science techniques. In the past, most investigations focused on selected cities to conduct different kinds of studies, such as the ecology of rats. No detailed maps existed incorporating the space-time dependence structure and uncertainty sources of the epidemic system and providing a composite space-time picture of the disease propagation characteristics. Results Informative spatiotemporal maps were generated that represented mortality rates and geographical spread of the disease, and epidemic indicator plots were derived that offered meaningful characterizations of the spatiotemporal disease distribution. The bubonic plague in India exhibited strong seasonal and geographical features. During its entire duration, the plague continued to invade new geographical areas, while it followed a re-emergence pattern at many localities; its rate changed significantly during each year and the mortality distribution exhibited space-time heterogeneous patterns; prevalence usually occurred in the autumn and spring, whereas the plague stopped moving towards new locations during the summers. Conclusion Modern stochastic modelling and geographical information science provide powerful means to study the spatiotemporal distribution of the bubonic plague epidemic under conditions of uncertainty and multi-sourced databases; to account for various forms of interdisciplinary knowledge; and to generate informative space-time maps of mortality rates and propagation patterns. To the best of our knowledge, this kind of plague maps and plots become available for the first time, thus providing novel perspectives concerning the distribution and space-time propagation of the deadly epidemic. Furthermore, systematic maps and indicator plots make possible the comparison of the spatial-temporal propagation patterns of different diseases. PMID:16545128

  5. Time-activity relationships to VOC personal exposure factors

    NASA Astrophysics Data System (ADS)

    Edwards, Rufus D.; Schweizer, Christian; Llacqua, Vito; Lai, Hak Kan; Jantunen, Matti; Bayer-Oglesby, Lucy; Künzli, Nino

    Social and demographic factors have been found to play a significant role in differences between time-activity patterns of population subgroups. Since time-activity patterns largely influence personal exposure to compounds as individuals move across microenvironments, exposure subgroups within the population may be defined by factors that influence daily activity patterns. Socio-demographic and environmental factors that define time-activity subgroups also define quantifiable differences in VOC personal exposures to different sources and individual compounds in the Expolis study. Significant differences in exposures to traffic-related compounds ethylbenzene, m- and p-xylene and o-xylene were observed in relation to gender, number of children and living alone. Categorization of exposures further indicated time exposed to traffic at work and time in a car as important determinants. Increased exposures to decane, nonane and undecane were observed for males, housewives and self-employed. Categorization of exposures indicated exposure subgroups related to workshop use and living downtown. Higher exposures to 3-carene and α-pinene commonly found in household cleaning products and fragrances were associated with more children, while exposures to traffic compounds ethylbenzene, m- and p-xylene and o-xylene were reduced with more children. Considerable unexplained variation remained in categorization of exposures associated with home product use and fragrances, due to individual behavior and product choice. More targeted data collection methods in VOC exposure studies for these sources should be used. Living alone was associated with decreased exposures to 2-methyl-1-propanol and 1-butanol, and traffic-related compounds. Identification of these subgroups may help to reduce the large amount of unexplained variation in VOC exposure studies. Further they may help in assessing impacts of urban planning that result in changes in behavior of individuals, resulting in shifts in the patterns of exposure experienced by the population.

  6. Comment on short-term variation in subjective sleepiness.

    PubMed

    Eriksen, Claire A; Akerstedt, Torbjörn; Kecklund, Göran; Akerstedt, Anna

    2005-12-01

    Subjective sleepiness at different times is often measured in studies on sleep loss, night work, or drug effects. However, the context at the time of rating may influence results. The present study examined sleepiness throughout the day at hourly intervals and during controlled activities [reading, writing, walking, social interaction (discussion), etc.] by 10-min. intervals for 3 hr. This was done on a normal working day preceded by a scheduled early rising (to invite sleepiness) for six subjects. Analysis showed a significant U-shaped pattern across the day with peaks in the early morning and late evening. A walk and social interaction were associated with low sleepiness, compared to sedentary and quiet office work. None of this was visible in the hourly ratings. There was also a pronounced afternoon increase in sleepiness, that was not observable with hourly ratings. It was concluded that there are large variations in sleepiness related to time of day and also to context and that sparse sampling of subjective sleepiness may miss much of this variation.

  7. A Temporal Mining Framework for Classifying Un-Evenly Spaced Clinical Data: An Approach for Building Effective Clinical Decision-Making System.

    PubMed

    Jane, Nancy Yesudhas; Nehemiah, Khanna Harichandran; Arputharaj, Kannan

    2016-01-01

    Clinical time-series data acquired from electronic health records (EHR) are liable to temporal complexities such as irregular observations, missing values and time constrained attributes that make the knowledge discovery process challenging. This paper presents a temporal rough set induced neuro-fuzzy (TRiNF) mining framework that handles these complexities and builds an effective clinical decision-making system. TRiNF provides two functionalities namely temporal data acquisition (TDA) and temporal classification. In TDA, a time-series forecasting model is constructed by adopting an improved double exponential smoothing method. The forecasting model is used in missing value imputation and temporal pattern extraction. The relevant attributes are selected using a temporal pattern based rough set approach. In temporal classification, a classification model is built with the selected attributes using a temporal pattern induced neuro-fuzzy classifier. For experimentation, this work uses two clinical time series dataset of hepatitis and thrombosis patients. The experimental result shows that with the proposed TRiNF framework, there is a significant reduction in the error rate, thereby obtaining the classification accuracy on an average of 92.59% for hepatitis and 91.69% for thrombosis dataset. The obtained classification results prove the efficiency of the proposed framework in terms of its improved classification accuracy.

  8. Continuity of care in community midwifery.

    PubMed

    Bowers, John; Cheyne, Helen; Mould, Gillian; Page, Miranda

    2015-06-01

    Continuity of care is often critical in delivering high quality health care. However, it is difficult to achieve in community health care where shift patterns and a need to minimise travelling time can reduce the scope for allocating staff to patients. Community midwifery is one example of such a challenge in the National Health Service where postnatal care typically involves a series of home visits. Ideally mothers would receive all of their antenatal and postnatal care from the same midwife. Minimising the number of staff-handovers helps ensure a better relationship between mothers and midwives, and provides more opportunity for staff to identify emerging problems over a series of home visits. This study examines the allocation and routing of midwives in the community using a variant of a multiple travelling salesmen problem algorithm incorporating staff preferences to explore trade-offs between travel time and continuity of care. This algorithm was integrated in a simulation to assess the additional effect of staff availability due to shift patterns and part-time working. The results indicate that continuity of care can be achieved with relatively small increases in travel time. However, shift patterns are problematic: perfect continuity of care is impractical but if there is a degree of flexibility in the visit schedule, reasonable continuity is feasible.

  9. Incoherent optical generalized Hough transform: pattern recognition and feature extraction applications

    NASA Astrophysics Data System (ADS)

    Fernández, Ariel; Ferrari, José A.

    2017-05-01

    Pattern recognition and feature extraction are image processing applications of great interest in defect inspection and robot vision among others. In comparison to purely digital methods, the attractiveness of optical processors for pattern recognition lies in their highly parallel operation and real-time processing capability. This work presents an optical implementation of the generalized Hough transform (GHT), a well-established technique for recognition of geometrical features in binary images. Detection of a geometric feature under the GHT is accomplished by mapping the original image to an accumulator space; the large computational requirements for this mapping make the optical implementation an attractive alternative to digital-only methods. We explore an optical setup where the transformation is obtained, and the size and orientation parameters can be controlled, allowing for dynamic scale and orientation-variant pattern recognition. A compact system for the above purposes results from the use of an electrically tunable lens for scale control and a pupil mask implemented on a high-contrast spatial light modulator for orientation/shape variation of the template. Real-time can also be achieved. In addition, by thresholding of the GHT and optically inverse transforming, the previously detected features of interest can be extracted.

  10. Prosodic domain-initial effects on the acoustic structure of vowels

    NASA Astrophysics Data System (ADS)

    Fox, Robert Allen; Jacewicz, Ewa; Salmons, Joseph

    2003-10-01

    In the process of language change, vowels tend to shift in ``chains,'' leading to reorganizations of entire vowel systems over time. A long research tradition has described such patterns, but little is understood about what factors motivate such shifts. Drawing data from changes in progress in American English dialects, the broad hypothesis is tested that changes in vowel systems are related to prosodic organization and stress patterns. Changes in vowels under greater prosodic prominence correlate directly with, and likely underlie, historical patterns of shift. This study examines acoustic characteristics of vowels at initial edges of prosodic domains [Fougeron and Keating, J. Acoust. Soc. Am. 101, 3728-3740 (1997)]. The investigation is restricted to three distinct prosodic levels: utterance (sentence-initial), phonological phrase (strong branch of a foot), and syllable (weak branch of a foot). The predicted changes in vowels /e/ and /ɛ/ in two American English dialects (from Ohio and Wisconsin) are examined along a set of acoustic parameters: duration, formant frequencies (including dynamic changes over time), and fundamental frequency (F0). In addition to traditional methodology which elicits list-like intonation, a design is adapted to examine prosodic patterns in more typical sentence intonations. [Work partially supported by NIDCD R03 DC005560-01.

  11. Self-similar transmission patterns induced by magnetic field effects in graphene

    NASA Astrophysics Data System (ADS)

    Rodríguez-González, R.; Rodríguez-Vargas, I.; Díaz-Guerrero, D. S.; Gaggero-Sager, L. M.

    2018-07-01

    In this work we study the propagation of Dirac electrons through Cantor-like structures in graphene. In concrete, we are considering structures with magnetic and electrostatic barriers arrange in Cantor-like fashion. The Dirac-like equation and the transfer matrix approach have been used to obtain the transmission properties. We found self-similar patterns in the transmission probability or transmittance once the magnetic field is incorporated. Moreover, these patterns can be connected with other ones at different scales through well-defined scaling rules. In particular, we have found two scaling rules that become a useful tool to describe the self-similarity of our system. The first expression is related to the generation and the second one to the length of the Cantor-like structure. As far as we know it is the first time that a special self-similar structure in conjunction with magnetic field effects give rise to self-similar transmission patterns. It is also important to remark that according to our knowledge it is fundamental to break some symmetry of graphene in order to obtain self-similar transmission properties. In fact, in our case the time-reversal symmetry is broken by the magnetic field effects.

  12. Working the night shift: a necessary time for training or a risk to health and safety?

    PubMed

    Morrison, I; Flower, D; Hurley, J; McFadyen, R J

    2013-01-01

    The European Working Time Directive (EWTD) limits excessive night shifts and restricts the working week to no more than 48 hours. The underlying rationale is to minimise the health risks to all workers. Here we debate the impact of night rotas for doctors-in-training on patient safety and medical education; when the EWTD was agreed these topics may not have been considered, either systematically or objectively. The impacts of diurnal rhythms on human functions affect all night workers, but the nature of rostered medical and surgical work has little precedent in other industries or even in the contracts of other healthcare staff. For example, rostered night duties need to be distinguished from permanent night shift work. On-call medical night work from training doctors is generally required for short periods and usually involves fewer patients. It is an important time in training, where clinical responsibility and decision-making can be matured in a supervised setting. To comply with the EWTD most hospitals have adopted rota patterns that aim to cover the clinical needs, while ensuring no doctor works for more than 48 hours in an average working week. To monitor this process longterm studies are necessary to evaluate effects on a doctor's health and on patient care generally. The EWTD has also led to a loss of continuity of patient care; does this really matter?

  13. Team-level flexibility, work–home spillover, and health behavior

    PubMed Central

    Moen, Phyllis; Fan, Wen; Kelly, Erin L.

    2013-01-01

    Drawing on two waves of survey data conducted six months apart in 2006, this study examined the impacts of a team-level flexibility initiative (ROWE – Results Only Work Environment) on changes in the work-home spillover and health behavior of employees at the Midwest headquarters of a large US corporation. Using cluster analysis, we identified three distinct baseline spillover constellations: employees with high negative spillover, high positive spillover, and low overall spillover. Within-team spillover measures were highly intercorrelated, suggesting that work teams as well as individuals have identifiable patterns of spillover. Multilevel analyses showed ROWE reduced individual- and team-level negative work-home spillover but not positive work-home spillover or spillover from home-to-work. ROWE also promoted employees’ health behaviors: increasing the odds of quitting smoking, decreasing smoking frequency, and promoting perceptions of adequate time for healthy meals. Trends suggest that ROWE also decreased the odds of excessive drinking and improved sleep adequacy and exercise frequency. Some health behavior effects were mediated via reduced individual-level negative work-home spillover (exercise frequency, adequate time for sleep) and reduced team-level negative work-home spillover (smoking frequency, exercise frequency, and adequate time for sleep). While we found no moderating effects of gender, ROWE especially improved the exercise frequency of singles and reduced the smoking frequency of employees with low overall spillover at baseline. PMID:23517706

  14. Metabolic and mechanical aspects of foot landing type, forefoot and rearfoot strike, in human running.

    PubMed

    Ardigò, L P; Lafortuna, C; Minetti, A E; Mognoni, P; Saibene, F

    1995-09-01

    The study was undertaken to assess the metabolic and the mechanical aspects of two different foot strike patterns in running, i.e. forefoot and rearfoot striking (FFS and RFS), and to understand whether there is some advantage for a runner to use one or the other of the two landing styles. Eight subjects performed two series of runs (FFS and RFS) on a treadmill at an average speed of 2.50, 2.78, 3.06, 3.33, 3.61, 3.89, 4.17 m s-1. Step frequency, oxygen uptake, mechanical work, and its two components, external and internal, were measured. No differences were found for step frequency, mechanical internal work per unit time and oxygen uptake, while external and total mechanical work per unit time were significantly higher, 7-12%, for FFS. The higher external work was the result of an increase of the work performed against both gravitational and inertial forces. As the energy expenditure was the same it has been speculated that a higher storage and release of energy takes place in the elastic structures of the lower leg with FFS. In a different series of experiments on six subjects contact time, time of deceleration and time of acceleration were measured by means of a video camera while running on the treadmill at 2.50, 3.33 and 4.17 m s-1, both FFS and RFS. Time of deceleration is similar for FFS and RFS, but contact time and time of acceleration are shorter, respectively 12 and 25%, for FFS.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Template-guided highly aligned, nano-scale wrinkle structure on a large-area

    NASA Astrophysics Data System (ADS)

    Lim, Jongcheon; Kim, Pilnam

    This study presents a novel technique to induce aligned, nano-scale wrinkle on a polysiloxane-based UV curable resin. There have been studies on generating randomized sub-micron wrinkle using oxygen plasma treatment which causes equibiaxial compressive stress on the film surface. Few works have been reported on how to control the surface wrinkle orientation. Currently available approaches for regulating the wrinkle pattern typically require polydimethylsiloxane (PDMS)-based bilayer system under uniaxial stress condition which hampers various technological applications. Here, we demonstrate a method to generate aligned wrinkle with UV curable polymers. Highly regular array of nanoscale wrinkles were formed by elastic buckling of bilayered UV curable resin, resulting from a combination of confinement effect and anchor-guided propagation of structure. The wrinkle tends to align uniformly lateral to the template pattern as the resin filled in the pattern forms more convex meniscus. The wavelength of the wrinkle was controlled by UV exposure time yielding as small as 170nm. From our results, we suggest the confinement provided by the template pattern may have affected the direction of thin film's expansion yielding unidirectional compressive stress. This work was supported by Samsung Research Funding Center of Samsung Electronics under Project Number SRFC-IT1402-02.

  16. Patterns of Alcohol Use and Consequences Among Empirically Derived Sexual Minority Subgroups

    PubMed Central

    Talley, Amelia E.; Sher, Kenneth J.; Steinley, Douglas; Wood, Phillip K.; Littlefield, Andrew K.

    2012-01-01

    Objective: The current study develops an empirically determined classification of sexual orientation developmental patterns based on participants’ annual reports of self-identifications, sexual attractions, and sexual behaviors during the first 4 years of college. A secondary aim of the current work was to examine trajectories of alcohol involvement among identified subgroups. Method: Data were drawn from a subsample of a longitudinal study of incoming first-time college students at a large, public university (n = 2,068). Longitudinal latent class analysis was used to classify sexual minority participants into empirically derived subgroups based on three self-reported facets of sexual orientation. Multivariate repeated-measures analyses were conducted to examine how trajectories of alcohol involvement varied by sexual orientation class membership. Results: Four unique subclasses of sexual orientation developmental patterns were identified for males and females: one consistently exclusively heterosexual group and three sexual minority groups. Despite generally similar alcohol use patterns among subclasses, certain sexual minority subgroups reported elevated levels of alcohol-related negative consequences and maladaptive motivations for use throughout college compared with their exclusively heterosexual counterparts. Conclusions: Elevations in coping and conformity motivations for alcohol use were seen among those subgroups that also evidenced heightened negative alcohol-related consequences. Implications and limitations of the current work are discussed. PMID:22333337

  17. Retrospective lifetime dietary patterns predict cognitive performance in community-dwelling older Australians.

    PubMed

    Hosking, Diane E; Nettelbeck, Ted; Wilson, Carlene; Danthiir, Vanessa

    2014-07-28

    Dietary intake is a modifiable exposure that may have an impact on cognitive outcomes in older age. The long-term aetiology of cognitive decline and dementia, however, suggests that the relevance of dietary intake extends across the lifetime. In the present study, we tested whether retrospective dietary patterns from the life periods of childhood, early adulthood, adulthood and middle age predicted cognitive performance in a cognitively healthy sample of 352 older Australian adults >65 years. Participants completed the Lifetime Diet Questionnaire and a battery of cognitive tests designed to comprehensively assess multiple cognitive domains. In separate regression models, lifetime dietary patterns were the predictors of cognitive factor scores representing ten constructs derived by confirmatory factor analysis of the cognitive test battery. All regression models were progressively adjusted for the potential confounders of current diet, age, sex, years of education, English as native language, smoking history, income level, apoE ɛ4 status, physical activity, other past dietary patterns and health-related variables. In the adjusted models, lifetime dietary patterns predicted cognitive performance in this sample of older adults. In models additionally adjusted for intake from the other life periods and mechanistic health-related variables, dietary patterns from the childhood period alone reached significance. Higher consumption of the 'coffee and high-sugar, high-fat extras' pattern predicted poorer performance on simple/choice reaction time, working memory, retrieval fluency, short-term memory and reasoning. The 'vegetable and non-processed' pattern negatively predicted simple/choice reaction time, and the 'traditional Australian' pattern positively predicted perceptual speed and retrieval fluency. Identifying early-life dietary antecedents of older-age cognitive performance contributes to formulating strategies for delaying or preventing cognitive decline.

  18. Considerations for fine hole patterning for the 7nm node

    NASA Astrophysics Data System (ADS)

    Yaegashi, Hidetami; Oyama, Kenichi; Hara, Arisa; Natori, Sakurako; Yamauchi, Shohei; Yamato, Masatoshi; Koike, Kyohei

    2016-03-01

    One of the practical candidates to produce 7nm node logic devices is to use the multiple patterning with 193-immersion exposure. For the multiple patterning, it is important to evaluate the relation between the number of mask layer and the minimum pitch systematically to judge the device manufacturability. Although the number of the time of patterning, namely LE(Litho-Etch) ^ x-time, and overlay steps have to be reduced, there are some challenges in miniaturization of hole size below 20nm. Various process fluctuations on contact hole have a direct impact on device performance. According to the technical trend, 12nm diameter hole on 30nm-pitch hole will be needed on 7nm node. Extreme ultraviolet lithography (EUV) and Directed self-assembly (DSA) are attracting considerable attention to obtain small feature size pattern, however, 193-immersion still has the potential to extend optical lithography cost-effectively for sub-7nm node. The objective of this work is to study the process variation challenges and resolution in post-processing for the CD-bias control to meet sub-20nm diameter contact hole. Another pattern modulation is also demonstrated during post-processing step for hole shrink. With the realization that pattern fidelity and pattern placement management will limit scaling long before devices and interconnects fail to perform intrinsically, the talk will also outline how circle edge roughness (CER) and Local-CD uniformity can correct efficiency. On the other hand, 1D Gridded-Design-Rules layout (1D layout) has simple rectangular shapes. Also, we have demonstrated CD-bias modification on short trench pattern to cut grating line for its fabrication.

  19. Predicting Forearm Physical Exposures During Computer Work Using Self-Reports, Software-Recorded Computer Usage Patterns, and Anthropometric and Workstation Measurements.

    PubMed

    Huysmans, Maaike A; Eijckelhof, Belinda H W; Garza, Jennifer L Bruno; Coenen, Pieter; Blatter, Birgitte M; Johnson, Peter W; van Dieën, Jaap H; van der Beek, Allard J; Dennerlein, Jack T

    2017-12-15

    Alternative techniques to assess physical exposures, such as prediction models, could facilitate more efficient epidemiological assessments in future large cohort studies examining physical exposures in relation to work-related musculoskeletal symptoms. The aim of this study was to evaluate two types of models that predict arm-wrist-hand physical exposures (i.e. muscle activity, wrist postures and kinematics, and keyboard and mouse forces) during computer use, which only differed with respect to the candidate predicting variables; (i) a full set of predicting variables, including self-reported factors, software-recorded computer usage patterns, and worksite measurements of anthropometrics and workstation set-up (full models); and (ii) a practical set of predicting variables, only including the self-reported factors and software-recorded computer usage patterns, that are relatively easy to assess (practical models). Prediction models were build using data from a field study among 117 office workers who were symptom-free at the time of measurement. Arm-wrist-hand physical exposures were measured for approximately two hours while workers performed their own computer work. Each worker's anthropometry and workstation set-up were measured by an experimenter, computer usage patterns were recorded using software and self-reported factors (including individual factors, job characteristics, computer work behaviours, psychosocial factors, workstation set-up characteristics, and leisure-time activities) were collected by an online questionnaire. We determined the predictive quality of the models in terms of R2 and root mean squared (RMS) values and exposure classification agreement to low-, medium-, and high-exposure categories (in the practical model only). The full models had R2 values that ranged from 0.16 to 0.80, whereas for the practical models values ranged from 0.05 to 0.43. Interquartile ranges were not that different for the two models, indicating that only for some physical exposures the full models performed better. Relative RMS errors ranged between 5% and 19% for the full models, and between 10% and 19% for the practical model. When the predicted physical exposures were classified into low, medium, and high, classification agreement ranged from 26% to 71%. The full prediction models, based on self-reported factors, software-recorded computer usage patterns, and additional measurements of anthropometrics and workstation set-up, show a better predictive quality as compared to the practical models based on self-reported factors and recorded computer usage patterns only. However, predictive quality varied largely across different arm-wrist-hand exposure parameters. Future exploration of the relation between predicted physical exposure and symptoms is therefore only recommended for physical exposures that can be reasonably well predicted. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  20. Lifetime achievement patterns, retirement and life satisfaction of gifted aged women.

    PubMed

    Holahan, C K

    1981-11-01

    The relationship of lifetime achievement patterns and retirement to life satisfaction for gifted aging women was investigated. Participants were 352 women in Terman's study of the gifted who were surveyed in 1977 at a mean age of 66. Lifetime achievement pattern was defined by either homemaker, job, or career work history. Dependent variables included health, happiness, life satisfaction, work attitudes, ambitions and aspirations, and participation in leisure activities. Results showed variations on life satisfaction measures as a function of lifetime career, with job holders generally less satisfied. There was a significant interaction between marital status and work pattern on overall life satisfaction suggesting an additive negative effect on the older woman of loss of spouse and a work history of working for income alone. Activity involvement varied as a function of retirement status and was differentially related to life satisfaction as a function of retirement status and career pattern.

  1. Robust reconstruction of time-resolved diffraction from ultrafast streak cameras

    PubMed Central

    Badali, Daniel S.; Dwayne Miller, R. J.

    2017-01-01

    In conjunction with ultrafast diffraction, streak cameras offer an unprecedented opportunity for recording an entire molecular movie with a single probe pulse. This is an attractive alternative to conventional pump-probe experiments and opens the door to studying irreversible dynamics. However, due to the “smearing” of the diffraction pattern across the detector, the streaking technique has thus far been limited to simple mono-crystalline samples and extreme care has been taken to avoid overlapping diffraction spots. In this article, this limitation is addressed by developing a general theory of streaking of time-dependent diffraction patterns. Understanding the underlying physics of this process leads to the development of an algorithm based on Bayesian analysis to reconstruct the time evolution of the two-dimensional diffraction pattern from a single streaked image. It is demonstrated that this approach works on diffraction peaks that overlap when streaked, which not only removes the necessity of carefully choosing the streaking direction but also extends the streaking technique to be able to study polycrystalline samples and materials with complex crystalline structures. Furthermore, it is shown that the conventional analysis of streaked diffraction can lead to erroneous interpretations of the data. PMID:28653022

  2. Personnel resources in physical therapy: an analysis of supply, career patterns, and methods to enhance availability.

    PubMed

    Gwyer, J

    1995-01-01

    Describing the ever-changing supply and demand for physical therapy personnel in the United States is an intricate, complex, and profoundly significant task for the profession. In this article, a review of data relating to the supply of physical therapy personnel in the work force and their typical career patterns is presented. The estimates of the numbers of physical therapists and physical therapist assistants are discussed, as are problems associated with such estimates. Studies of career patterns of physical therapists are compared. Changes in the participation rates of women in the physical therapy work force over the last three decades are described. Career expectations, defined as both length and pattern of work-force participation, of entering physical therapy professionals are presented. Strategies to adjust the work-force participation of personnel through changes in the educational process, career patterns, and practice patterns are discussed.

  3. A continuous time-resolved measure decoded from EEG oscillatory activity predicts working memory task performance.

    PubMed

    Astrand, Elaine

    2018-06-01

    Working memory (WM), crucial for successful behavioral performance in most of our everyday activities, holds a central role in goal-directed behavior. As task demands increase, inducing higher WM load, maintaining successful behavioral performance requires the brain to work at the higher end of its capacity. Because it is depending on both external and internal factors, individual WM load likely varies in a continuous fashion. The feasibility to extract such a continuous measure in time that correlates to behavioral performance during a working memory task remains unsolved. Multivariate pattern decoding was used to test whether a decoder constructed from two discrete levels of WM load can generalize to produce a continuous measure that predicts task performance. Specifically, a linear regression with L2-regularization was chosen with input features from EEG oscillatory activity recorded from healthy participants while performing the n-back task, [Formula: see text]. The feasibility to extract a continuous time-resolved measure that correlates positively to trial-by-trial working memory task performance is demonstrated (r  =  0.47, p  <  0.05). It is furthermore shown that this measure allows to predict task performance before action (r  =  0.49, p  <  0.05). We show that the extracted continuous measure enables to study the temporal dynamics of the complex activation pattern of WM encoding during the n-back task. Specifically, temporally precise contributions of different spectral features are observed which extends previous findings of traditional univariate approaches. These results constitute an important contribution towards a wide range of applications in the field of cognitive brain-machine interfaces. Monitoring mental processes related to attention and WM load to reduce the risk of committing errors in high-risk environments could potentially prevent many devastating consequences or using the continuous measure as neurofeedback opens up new possibilities to develop novel rehabilitation techniques for individuals with degraded WM capacity.

  4. A continuous time-resolved measure decoded from EEG oscillatory activity predicts working memory task performance

    NASA Astrophysics Data System (ADS)

    Astrand, Elaine

    2018-06-01

    Objective. Working memory (WM), crucial for successful behavioral performance in most of our everyday activities, holds a central role in goal-directed behavior. As task demands increase, inducing higher WM load, maintaining successful behavioral performance requires the brain to work at the higher end of its capacity. Because it is depending on both external and internal factors, individual WM load likely varies in a continuous fashion. The feasibility to extract such a continuous measure in time that correlates to behavioral performance during a working memory task remains unsolved. Approach. Multivariate pattern decoding was used to test whether a decoder constructed from two discrete levels of WM load can generalize to produce a continuous measure that predicts task performance. Specifically, a linear regression with L2-regularization was chosen with input features from EEG oscillatory activity recorded from healthy participants while performing the n-back task, n\\in [1,2] . Main results. The feasibility to extract a continuous time-resolved measure that correlates positively to trial-by-trial working memory task performance is demonstrated (r  =  0.47, p  <  0.05). It is furthermore shown that this measure allows to predict task performance before action (r  =  0.49, p  <  0.05). We show that the extracted continuous measure enables to study the temporal dynamics of the complex activation pattern of WM encoding during the n-back task. Specifically, temporally precise contributions of different spectral features are observed which extends previous findings of traditional univariate approaches. Significance. These results constitute an important contribution towards a wide range of applications in the field of cognitive brain–machine interfaces. Monitoring mental processes related to attention and WM load to reduce the risk of committing errors in high-risk environments could potentially prevent many devastating consequences or using the continuous measure as neurofeedback opens up new possibilities to develop novel rehabilitation techniques for individuals with degraded WM capacity.

  5. Time-activity patterns of pregnant women and changes during the course of pregnancy.

    PubMed

    Nethery, Elizabeth; Brauer, Michael; Janssen, Patti

    2009-03-01

    Numerous studies suggest that in utero exposures to environmental contaminants are associated with fetal development, congenital anomalies, learning difficulties or other health impacts later in life. Although location and time-activity data have been used to model exposure to specific contaminants in epidemiological studies, little information is available about time-activity patterns of pregnant women. We measured changes in location-based activity patterns over the course of pregnancy (48-h periods, during two or three trimesters) using a self-reported time-activity log among a nonrandom sample of pregnant women (n=62). We assessed the influence of demographics and personal factors on changes in activity over pregnancy using mixed effects regression models. Increasing weeks of pregnancy was a significant predictor for increased time spent at home (1 h/day increase for each trimester of pregnancy), after adjusting for income (2.6 more h/day at home in lowest income group), work status (3.5 more h/day at home for nonworkers) and other children in the family (1.5 more h/day at home with other children). No other measured activities (time outdoors, time in transit modalities or time in other indoor locations) were related to weeks of pregnancy. As our results indicate that pregnant women tend to spend more time at home during the latter stages of pregnancy, future exposure and epidemiological research should consider the potential increase in home-based exposures (i.e., indoor air pollution or chemicals in the home) late in pregnancy, and increased confidence in exposure proxies based on home locations or characteristics during the same period.

  6. Leadership and Presenteeism among Scientific Staff: The Role of Accumulation of Work and Time Pressure

    PubMed Central

    Dietz, Carolin; Scheel, Tabea

    2017-01-01

    The present study examines the joint roles of leadership and stressors for presenteeism of scientific staff. Leaders may have an impact on employees' health, both directly through interpersonal interactions and by shaping their working conditions. In the field of science, this impact could be special because of the mentoring relationships between the employees (e.g., PhD students) and their supervisors (e.g., professors). Based on the job demands-resources framework (JD-R), we hypothesized that the pressure to be present at the workplace induced by supervisors (supervisorial pressure) is directly related to employees' presenteeism as well as indirectly via perceptions of time pressure. The conservation of resources theory (COR) states that resource loss resulting from having to deal with job demands weakens the resource pool and therefore the capacity to deal with other job demands. Thus, we hypothesized that accumulation of work moderates the relationship between supervisorial pressure and time pressure, such that the relationship is stronger when accumulation of work is high compared to if accumulation of work is low. Cross-sectional data were obtained from 212 PhD students and postdocs of 30 scientific institutions in Germany. Analysis was performed using the SPSS macro PROCESS (Hayes, 2013). Supervisorial pressure was directly associated with higher presenteeism of employees and indirectly through increased time pressure. Moreover, supervisorial pressure and accumulation of work interacted to predict time pressure, but in an unexpected way. The positive relationship between supervisorial pressure and time pressure is stronger when accumulation is low compared to if accumulation of work is high. It seems possible that job stressors do not accumulate but substitute each other. Threshold models might explain the findings. Moreover, specific patterns of interacting job demands for scientific staff should be considered in absence management. PMID:29123497

  7. Pattern Formation

    NASA Astrophysics Data System (ADS)

    Hoyle, Rebecca

    2006-03-01

    From the stripes of a zebra and the spots on a leopard's back to the ripples on a sandy beach or desert dune, regular patterns arise everywhere in nature. The appearance and evolution of these phenomena has been a focus of recent research activity across several disciplines. This book provides an introduction to the range of mathematical theory and methods used to analyse and explain these often intricate and beautiful patterns. Bringing together several different approaches, from group theoretic methods to envelope equations and theory of patterns in large-aspect ratio-systems, the book also provides insight behind the selection of one pattern over another. Suitable as an upper-undergraduate textbook for mathematics students or as a fascinating, engaging, and fully illustrated resource for readers in physics and biology, Rebecca Hoyle's book, using a non-partisan approach, unifies a range of techniques used by active researchers in this growing field. Accessible description of the mathematical theory behind fascinating pattern formation in areas such as biology, physics and materials science Collects recent research for the first time in an upper level textbook Features a number of exercises - with solutions online - and worked examples

  8. Keeping the feet of the gods and the saints warm: mundane pragmatics in times of suffering and uncertainty.

    PubMed

    van Dongen, Els

    2008-12-01

    In this article the author writes about mundane pragmatics, or everyday deeds, in times of suffering and uncertainty. Such pragmatics differ from cultural practices such as biomedical therapies or individual health-seeking behaviour patterns. Medical anthropologists and others working in the field of health and illness often overlook such pragmatics. However, these actions are of great social value and express the connectedness and bonds between people. They also express our deep beliefs, hopes, powerlessness and vulnerability.

  9. Variation in marital quality in a national sample of divorced women.

    PubMed

    James, Spencer L

    2015-06-01

    Previous work has compared marital quality between stably married and divorced individuals. Less work has examined the possibility of variation among divorcés in trajectories of marital quality as divorce approaches. This study addressed that hole by first examining whether distinct trajectories of marital quality can be discerned among women whose marriages ended in divorce and, second, the profile of women who experienced each trajectory. Latent class growth analyses with longitudinal data from a nationally representative sample were used to "look backward" from the time of divorce. Although demographic and socioeconomic variables from this national sample did not predict the trajectories well, nearly 66% of divorced women reported relatively high levels of both happiness and communication and either low or moderate levels of conflict. Future research including personality or interactional patterns may lead to theoretical insights about patterns of marital quality in the years leading to divorce. (c) 2015 APA, all rights reserved).

  10. An Exploration of Smoking-to-Vaping Transition Attempts Using a "Smart" Electronic Nicotine Delivery System.

    PubMed

    Blank, Mei-Ling; Hoek, Janet; George, Mark; Gendall, Philip; Conner, Tamlin S; Thrul, Johannes; Ling, Pamela M; Langlotz, Tobias

    2018-06-06

    Electronic nicotine delivery systems (ENDS) are used to aid smoking cessation attempts; however, many smokers continue to smoke while using an ENDS (dual use). Although uncertainty remains regarding whether specific ENDS patterns hinder or support successful smoking cessation, recent advances in "smart" technology allow passive and active recording of behaviors in real time, enabling more detailed insights into how smoking and vaping patterns may coevolve. We describe patterns of ENDS initiation, and subsequent use, including any changes in cigarette consumption, among daily smokers using a "smart" ENDS (S-ENDS) to quit smoking. An 8-week long mixed-methods feasibility study used Bluetooth-enabled S-ENDS that passively recorded real-time device use by participants (n = 11). Daily surveys administered via smartphones collected data on self-reported cigarette consumption. All 11 participants were dual users, at least initially, during their quit attempt. We observed three provisional vaping and smoking patterns: immediate and intensive ENDS initiation coupled with immediate, dramatic, and sustained smoking reduction, leading to smoking abstinence; gradual ENDS uptake with gradual smoking reductions, leading to daily dual use throughout the study period; and ENDS experimentation with return to exclusive smoking. For six participants, the patterns observed in week 1 were similar to the vaping and smoking patterns observed throughout the rest of the study period. Technological advances now allow fine-grained description of ENDS use and smoking patterns. Larger and longer studies describing smoking-to-vaping patterns, and estimating associations with smoking outcomes, could inform ENDS-specific cessation advice promoting full transition from smoking to exclusive ENDS use. The use of an S-ENDS that recorded real-time device use among daily smokers engaged in a quit attempt provides insight into patterns and trajectories of dual use (continuing to smoke while using ENDS), and the possible associations between ENDS initiation, subsequent use, and smoking cessation outcomes. Such work could support more targeted cessation counseling and technical advice for smokers using ENDS to quit smoking, reduce the risk of users developing long-term dual use patterns, and enhance the contributions ENDS may make to reducing smoking prevalence.

  11. Two-Dimensional Optical CDMA System Parameters Limitations for Wavelength Hopping/Time-Spreading Scheme based on Simulation Experiment

    NASA Astrophysics Data System (ADS)

    Kandouci, Chahinaz; Djebbari, Ali

    2018-04-01

    A new family of two-dimensional optical hybrid code which employs zero cross-correlation (ZCC) codes, constructed by the balanced incomplete block design BIBD, as both time-spreading and wavelength hopping patterns are used in this paper. The obtained codes have both off-peak autocorrelation and cross-correlation values respectively equal to zero and unity. The work in this paper is a computer experiment performed using Optisystem 9.0 software program as a simulator to determine the wavelength hopping/time spreading (WH/TS) OCDMA system performances limitations. Five system parameters were considered in this work: the optical fiber length (transmission distance), the bitrate, the chip spacing and the transmitted power. This paper shows for what sufficient system performance parameters (BER≤10-9, Q≥6) the system can stand for.

  12. Interruptions and multitasking in surgery: a multicentre observational study of the daily work patterns of doctors and nurses.

    PubMed

    Bellandi, Tommaso; Cerri, Alessandro; Carreras, Giulia; Walter, Scott; Mengozzi, Cipriana; Albolino, Sara; Mastrominico, Eleonora; Renzetti, Fernando; Tartaglia, Riccardo; Westbrook, Johanna

    2018-01-01

    The aim of this study was to obtain baseline data on doctors' and nurses' work activities and rates of interruptions and multitasking to improve work organisation and processes. Data were collected in six surgical units with the WOMBAT (Work Observation Method by Activity Timing) tool. Results show that doctors and nurses received approximately 13 interruptions per hour, or one interruption every 4.5 min. Compared to doctors, nurses were more prone to interruptions in most activities, while doctors performed multitasking (33.47% of their time, 95% CI 31.84-35.17%) more than nurses (15.23%, 95% CI 14.24-16.25%). Overall, the time dedicated to patient care is relatively limited for both professions (37.21%, 95% CI 34.95-39.60% for doctors, 27.22%, 95% CI 25.18-29.60% for nurses) compared to the time spent for registration of data and professional communication, that accounts for two-thirds of doctors' time and nearly half of nurses' time. Further investigation is needed on strategies to manage job demands and professional communications. Practitioner Summary: This study offers further findings on the characteristics and frequency of multitasking and interruptions in surgery, with a comparison of how they affect doctors and nurses. Further investigation is needed to improve the management of job demands and communications according to the results.

  13. Working at the microscope: analysis of the activities involved in diagnostic pathology.

    PubMed

    Randell, Rebecca; Ruddle, Roy A; Quirke, Phil; Thomas, Rhys G; Treanor, Darren

    2012-02-01

    To study the current work practice of histopathologists to inform the design of digital microscopy systems. Four gastrointestinal histopathologists were video-recorded as they undertook their routine work. Analysis of the video data shows a range of activities beyond viewing slides involved in reporting a case. There is much overlapping of activities, supported by the 'eyes free' nature of the pathologists' interaction with the microscope. The order and timing of activities varies according to consultant. In order to support the work of pathologists adequately, digital microscopy systems need to provide support for a range of activities beyond viewing slides. Digital microscopy systems should support multitasking, while also providing flexibility so that pathologists can adapt their use of the technology to their own working patterns. © 2011 Blackwell Publishing Ltd.

  14. [Work-related behaviour and experience patterns and mental health: a study in psychotherapy trainees].

    PubMed

    Grundmann, Johanna; Sude, Kerstin; Löwe, Bernd; Wingenfeld, Katja

    2013-03-01

    In view of the fact that many reports have been published that emphasize the difficult conditions of the German psychotherapy training, the aim of this study was to investigate psychotherapy trainees´ work stress as well as work-related psychosocial risks and resources. Variables of interest were work-related behaviour and experience patterns (AVEM), effort-reward-imbalance, chronic stress and health-related quality of life. 321 participants completed an online survey. The distribution of work-related behaviour and experience patterns as well as the results regarding work overload and mental health are evidence of psychotherapy trainees' strain. AVEM-risk patterns are associated with effort-reward-imbalance, chronic stress and reduced mental health. These results clearly support claims for a modification of the psychotherapy training in Germany. © Georg Thieme Verlag KG Stuttgart · New York.

  15. A study examining the impact of 12-hour shifts on critical care staff.

    PubMed

    Richardson, Annette; Turnock, Christopher; Harris, Liz; Finley, Alison; Carson, Sarah

    2007-11-01

    Twelve-hour shifts contribute to flexible patterns of work, but the effects on delivery of direct care and staff fatigue are important topics for deeper examination. To examine the impact and implications of 12-hour shifts on critical care staff. A staged dual approach using two focus groups (n = 16) and questionnaires (n = 147) with critical care staff from three critical care units. Positive effects were found with planning and prioritizing care, improved relationships with patients/relatives, good-quality time off work and ease of travelling to work. Less favourable effects were with caring for patients in isolation cubicles and the impact on staff motivation and tiredness. Acceptable patterns of work were suggested for 'numbers of consecutive shifts' and 'rest periods between shifts'. Most participants believed 12-hour shifts should continue. The challenge is to ensure existing systems and practices develop to improve on the less positive effects of working 12-hour shifts. This study provides nurse managers with important and relevant staff views on the impact of working 12-hour shifts. In particular to those working within a critical care environment and suggests the challenge is to ensure existing systems and practices develop to improve on the less encouraging effects of working 12-hour shifts. It adds an understanding of the senior nurse's view on the positive and negative effects of managing and organizing staff off duty to safely run a department with 12-hour shifts.

  16. Perceptual and Physiological Responses to Jackson Pollock's Fractals

    PubMed Central

    Taylor, Richard P.; Spehar, Branka; Van Donkelaar, Paul; Hagerhall, Caroline M.

    2011-01-01

    Fractals have been very successful in quantifying the visual complexity exhibited by many natural patterns, and have captured the imagination of scientists and artists alike. Our research has shown that the poured patterns of the American abstract painter Jackson Pollock are also fractal. This discovery raises an intriguing possibility – are the visual characteristics of fractals responsible for the long-term appeal of Pollock's work? To address this question, we have conducted 10 years of scientific investigation of human response to fractals and here we present, for the first time, a review of this research that examines the inter-relationship between the various results. The investigations include eye tracking, visual preference, skin conductance, and EEG measurement techniques. We discuss the artistic implications of the positive perceptual and physiological responses to fractal patterns. PMID:21734876

  17. Inertia-induced dendriticlike patterns in lifting Hele-Shaw flows

    NASA Astrophysics Data System (ADS)

    Anjos, Pedro H. A.; Dias, Eduardo O.; Miranda, José A.

    2017-01-01

    The lifting Hele-Shaw cell problem is a variant of the classical constant-gap Hele-Shaw situation in which the cell gap width is time dependent. Experiments on Newtonian fluid flows in lifting Hele-Shaw cells with large lifting velocities reveal the development of dendriticlike fingered structures that compete among themselves. The usual Darcy law description of the problem, where inertial effects are neglected, has not been able to explain the origin of these competing sidebranched patterns. In this work we use a generalized Darcy law and a perturbative mode-coupling theory to investigate the impact of inertia on the pattern-forming dynamics of the system. Two main results are deduced: Inertia induces a mechanism for finger sidebranching formation and favors the intensification of finger competition events.

  18. The use of functional data analysis to study variability in childrens speech: Further data

    NASA Astrophysics Data System (ADS)

    Koenig, Laura L.; Lucero, Jorge C.

    2002-05-01

    Much previous research has reported increased token-to-token variability in children relative to adults, but the sources and implications of this variability remain matters of debate. Recently, functional data analysis has been used as a tool to gain greater insight into the nature of variability in children's and adults' speech data. In FDA, signals are time-normalized using a smooth function of time. The magnitude of the time-warping function provides an index of phasing (temporal) variability, and a separate index of amplitude variability is calculated from the time-normalized signal. Here, oral airflow data are analyzed from 5-year-olds, 10-year-olds, and adult women producing laryngeal and oral fricatives (/h, s, z/). The preliminary FDA results show that children generally have higher temporal and amplitude indices than adults, suggesting greater variability both in gestural timing and magnitude. However, individual patterns are evident in the relative magnitude of the two indices, and in which consonants show the highest values. The time-varying patterns of flow variability over time in /s/ are also explored as a method of inferring relative variability among laryngeal and oral gestures. [Work supported by NIH and CNPq, Brazil.

  19. Finding a Fit or Developing It: Implicit Theories About Achieving Passion for Work.

    PubMed

    Chen, Patricia; Ellsworth, Phoebe C; Schwarz, Norbert

    2015-10-01

    "Passion for work" has become a widespread phrase in popular discourse. Two contradictory lay perspectives have emerged on how passion for work is attained, which we distill into the fit and develop implicit theories. Fit theorists believe that passion for work is achieved through finding the right fit with a line of work; develop theorists believe that passion is cultivated over time. Four studies examined the expectations, priorities, and outcomes that characterize these implicit theories. Our results show that these beliefs elicit different motivational patterns, but both can facilitate vocational well-being and success. This research extends implicit theory scholarship to the work domain and provides a framework that can fruitfully inform career advising, life coaching, mentorship, and employment policies. © 2015 by the Society for Personality and Social Psychology, Inc.

  20. Directed self assembly of block copolymers using chemical patterns with sidewall guiding lines, backfilled with random copolymer brushes.

    PubMed

    Pandav, Gunja; Durand, William J; Ellison, Christopher J; Willson, C Grant; Ganesan, Venkat

    2015-12-21

    Recently, alignment of block copolymer domains has been achieved using a topographically patterned substrate with a sidewall preferential to one of the blocks. This strategy has been suggested as an option to overcome the patterning resolution challenges facing chemoepitaxy strategies, which utilize chemical stripes with a width of about half the period of block copolymer to orient the equilibrium morphologies. In this work, single chain in mean field simulation methodology was used to study the self assembly of symmetric block copolymers on topographically patterned substrates with sidewall interactions. Random copolymer brushes grafted to the background region (space between patterns) were modeled explicitly. The effects of changes in pattern width, film thicknesses and strength of sidewall interaction on the resulting morphologies were examined and the conditions which led to perpendicular morphologies required for lithographic applications were identified. A number of density multiplication schemes were studied in order to gauge the efficiency with which the sidewall pattern can guide the self assembly of block copolymers. The results indicate that such a patterning technique can potentially utilize pattern widths of the order of one-two times the period of block copolymer and still be able to guide ordering of the block copolymer domains up to 8X density multiplication.

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