545 research outputs found

    How Do Adolescents Spell Time Use?

    Get PDF
    We investigate how household disadvantage affects the time use of 15-18 year-olds using 2003-2006 data from the American Time Use Survey. Applying competing-risk hazard models, we distinguish between the incidence and duration of activities and incorporate the daily time constraint. We find that teens living in disadvantaged households spend less time in non-classroom schooling activities than other teens. Girls spend some of this time in work activities, suggesting they are taking on adult roles. However we find more evidence of substitution into unsupervised activities, suggesting that it may be less structured environments that reduce educational investment.event history models, adolescence, time use

    How do Adolescents Spell Time Use?

    Get PDF
    We investigate how household disadvantage affects the time use of 15-18 year-olds using 2003- 2006 data from the American Time Use Survey. Applying competing-risk hazard models, we distinguish between the incidence and duration of activities and incorporate the daily time constraint. We find that teens living in disadvantaged households spend less time in nonclassroom schooling activities than other teens. Girls spend some of this time in work activities, suggesting they are taking on adult roles. However we find more evidence of substitution into unsupervised activities, suggesting that it may be less structured environments that reduce educational investment.Time use, adolescence, event history models

    "Parental Child Care in Single Parent, Cohabiting, and Married Couple Families: Time Diary Evidence from the United States and the United Kingdom"

    Get PDF
    This study uses time diary data from the 2003 American Time Use Survey and the United Kingdom Time Use Survey 2000 to examine the time that single, cohabiting, and married parents devote to caring for their children. Time spent in market work, in child care as a primary activity, and in child care as a passive activity are jointly modeled using a correlated, censored regression model. Separate estimates are provided by gender, by country, and by weekend/weekday day. We find no evidence that these time allocation decisions differ for cohabiting and married parents, but there is evidence that single persons allocate time differently - as might be expected, given different household time constraints. In the U.S. single fathers spend significantly more time in primary child care on weekdays and substantially less time in passive child care on weekends than their married or cohabiting counterparts, while in the UK single fathers spend significantly more time in passive child care on weekdays. Single fathers in each country report less time at work on weekdays than their married or cohabiting counterparts. In the U.S., single mothers work more than married or cohabiting mothers on weekdays, while single mothers in the United Kingdom work less than married or cohabiting mothers on all days.

    Differences in level of confidence in diabetes care between different groups of trainees: the TOPDOC diabetes study

    Get PDF
    Background There is an increasing prevalence of diabetes. Doctors in training, irrespective of specialty, will have patients with diabetes under their care. The aim of this further evaluation of the TOPDOC Diabetes Study data was to identify if there was any variation in confidence in managing diabetes depending on the geographical location of trainees and career aspirations. Methods An online national survey using a pre-validated questionnaire was administered to trainee doctors. A 4-point confidence rating scale was used to rate confidence in managing aspects of diabetes care and a 6-point scale used to quantify how often trainees would contribute to the management of patients with diabetes. Responses were grouped depending on which UK country trainees were based and their intended career choice. Results Trainees in Northern Ireland reported being less confident in IGT diagnosis, use of IV insulin and peri-operative management and were less likely to adjust oral treatment, contact specialist, educate lifestyle, and optimise treatment. Trainees in Scotland were less likely to contact a specialist, but more likely to educate on lifestyle, change insulin, and offer follow-up advice. In Northern Ireland, Undergraduate (UG) and Postgraduate (PG) training in diagnosis was felt less adequate, PG training in emergencies less adequate, and reporting of need for further training higher. Trainees in Wales felt UG training to be inadequate. In Scotland more trainees felt UG training in diagnosis and optimising treatment was inadequate. Physicians were more likely to report confidence in managing patients with diabetes and to engage in different aspects of diabetes care. Aspiring physicians were less likely to feel the need for more training in diabetes care; however a clear majority still felt they needed more training in all aspects of care. Conclusions Doctors in training have poor confidence levels dealing with diabetes related care issues. Although there is variability between different groups of trainees according to geographical location and career aspirations, this is a UK wide issue. There should be a UK wide standardised approach to improving training for junior doctors in diabetes care with local training guided by specific needs.</p

    Gas-grain simulation facility: Aerosol and particle research in microgravity

    Get PDF
    This document reports on the proceedings of the Gas-Grain Simulation Facility (GGSF) Science Workshop which was co-hosted by NASA Ames Research Center and Desert Research Institute, University of Nevada System, and held in Las Vegas, Nevada, on May 4-6, 1992. The intent of the workshop was to bring together the science community of potential GGSF experimenters, Science Working Group and staff members, and the Phase A contractor to review the Phase A design with the science participants and to facilitate communication between the science community and the hardware developers. The purpose of this report is to document the information disseminated at the workshop, to record the participants' review of the Phase A GGSF design concept and the current science and technical requirements for the Facility, and to respond to any questions or concerns that were raised at the Workshop. Recommendations for the future based on numerous discussions with the participants are documented, as well as science presentations and poster sessions that were given at the Workshop and a summary of 21 candidate experiments

    On the exact electric and magnetic fields of an electric dipole

    Full text link
    We derive from Jefimenko's equations a multipole expansion in order to obtain the exact expressions for the electric and magnetic fields of an electric dipole with an arbitrary time dependence. A few comments are also made about the usual expositions found in most common undergraduate and graduate textbooks as well as in the literature on this topic

    Testing the performance of risk prediction models to determine progression to referable diabetic retinopathy in an Irish type 2 diabetes cohort

    Get PDF
    Background /aims: To evaluate the performance of existing prediction models to determine risk of progression to referable diabetic retinopathy (RDR) using data from a prospective Irish cohort of people with type 2 diabetes (T2D). Methods: A cohort of 939 people with T2D followed prospectively was used to test the performance of risk prediction models developed in Gloucester, UK, and Iceland. Observed risk of progression to RDR in the Irish cohort was compared with that derived from each of the prediction models evaluated. Receiver operating characteristic curves assessed models' performance. Results: The cohort was followed for a total of 2929 person years during which 2906 screening episodes occurred. Among 939 individuals followed, there were 40 referrals (4%) for diabetic maculopathy, pre-proliferative DR and proliferative DR. The original Gloucester model, which includes results of two consecutive retinal screenings; a model incorporating, in addition, systemic biomarkers (HbA1c and serum cholesterol); and a model including results of one retinopathy screening, HbA1c, total cholesterol and duration of diabetes, had acceptable discriminatory power (area under the curve (AUC) of 0.69, 0.76 and 0.77, respectively). The Icelandic model, which combined retinopathy grading, duration and type of diabetes, HbA1c and systolic blood pressure, performed very similarly (AUC of 0.74). Conclusion: In an Irish cohort of people with T2D, the prediction models tested had an acceptable performance identifying those at risk of progression to RDR. These risk models would be useful in establishing more personalised screening intervals for people with T2D

    The genome as a record of environmental exposure.

    Get PDF
    Whole genome sequencing of human tumours has revealed distinct patterns of mutation that hint at the causative origins of cancer. Experimental investigations of the mutations and mutation spectra induced by environmental mutagens have traditionally focused on single genes. With the advent of faster cheaper sequencing platforms, it is now possible to assess mutation spectra in experimental models across the whole genome. As a proof of principle, we have examined the whole genome mutation profiles of mouse embryo fibroblasts immortalised following exposure to benzo[a]pyrene (BaP), ultraviolet light (UV) and aristolochic acid (AA). The results reveal that each mutagen induces a characteristic mutation signature: predominantly G→T mutations for BaP, C→T and CC→TT for UV and A→T for AA. The data are not only consistent with existing knowledge but also provide additional information at higher levels of genomic organisation. The approach holds promise for identifying agents responsible for mutations in human tumours and for shedding light on the aetiology of human cancer

    The driver landscape of sporadic chordoma.

    Get PDF
    Chordoma is a malignant, often incurable bone tumour showing notochordal differentiation. Here, we defined the somatic driver landscape of 104 cases of sporadic chordoma. We reveal somatic duplications of the notochordal transcription factor brachyury (T) in up to 27% of cases. These variants recapitulate the rearrangement architecture of the pathogenic germline duplications of T that underlie familial chordoma. In addition, we find potentially clinically actionable PI3K signalling mutations in 16% of cases. Intriguingly, one of the most frequently altered genes, mutated exclusively by inactivating mutation, was LYST (10%), which may represent a novel cancer gene in chordoma.Chordoma is a rare often incurable malignant bone tumour. Here, the authors investigate driver mutations of sporadic chordoma in 104 cases, revealing duplications in notochordal transcription factor brachyury (T), PI3K signalling mutations, and mutations in LYST, a potential novel cancer gene in chordoma
    • …
    corecore