27 research outputs found

    Software reliability cases: the bridge between hardware, software and system safety and reliability

    Get PDF
    High integrity/high consequence systems must be safe and reliable; hence it is only logical that both software safety and software reliability cases should be developed. Risk assessments in safety cases evaluate the severity of the consequences of a hazard and the likelihood of it occurring. The likelihood is directly related to system and software reliability predictions. Software reliability cases, as promoted by SAE JA 1002 and 1003, provide a practical approach to bridge the gap between hardware reliability, software reliability, and system safety and reliability by using a common methodology and information structure. They also facilitate early insight into whether or not a project is on track for meeting stated safety and reliability goals, while facilitating an informed assessment by regulatory and/or contractual authorities

    Aerobic exercise alone results in clinically significant weight loss for men and women: Midwest Exercise Trial-2

    Get PDF
    This is the peer reviewed version of the following article: Donnelly, J. E., Honas, J. J., Smith, B. K., Mayo, M. S., Gibson, C. A., Sullivan, D. K., Lee, J., Herrmann, S. D., Lambourne, K. and Washburn, R. A. (2013), Aerobic exercise alone results in clinically significant weight loss for men and women: Midwest exercise trial 2. Obesity, 21: E219–E228. doi:10.1002/oby.20145, which has been published in final form at http://doi.org/10.1002/oby.20145. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.Exercise is recommended by public health agencies for weight management; however, the role of exercise is generally considered secondary to energy restriction. Few studies exist that have verified completion of exercise, measured the energy expenditure of exercise, and prescribed exercise with equivalent energy expenditure across individuals and genders. OBJECTIVE The objective of this study was to evaluate aerobic exercise, without energy restriction, on weight loss in sedentary overweight and obese men and women. DESIGN AND METHODS This investigation was a randomized, controlled, efficacy trial in 141 overweight and obese participants (body mass index, 31.0 ± 4.6 kg/m2; age 22.6 ± 3.9 years). Participants were randomized (2:2:1 ratio) to exercise at either 400 kcal/session or 600 kcal/session or to a non-exercise control. Exercise was supervised, 5 days/week, for 10 months. All participants were instructed to maintain usual ad libitum diets. Due to the efficacy design, completion of ≥ 90% of exercise sessions was an a priori definition of per protocol, and these participants were included in the analysis. RESULTS Weight loss from baseline to 10 months for the 400 and 600 kcal/session groups was 3.9 ± 4.9kg (4.3%) and 5.2 ± 5.6kg (5.7%), respectively compared to weight gain for controls of 0.5 ± 3.5kg (0.5%) (p<0.05). Differences for weight loss from baseline to 10 months between the exercise groups and differences between men and women within groups were not statistically significant. CONCLUSIONS Supervised exercise, with equivalent energy expenditure, results in clinically significant weight loss with no significant difference between men and women

    Physical activity and academic achievement across the curriculum (A + PAAC): rationale and design of a 3-year, cluster-randomized trial

    Get PDF
    Abstract Background Improving academic achievement and reducing the rates of obesity in elementary school students are both of considerable interest. Increased physical activity during academic instruction time during school offers a potential intervention to address both issues. A program titled &#8220;Physical Activity Across the Curriculum&#8221; (PAAC) was developed in which classroom teachers in 22 elementary schools were trained to deliver academic instruction using physical activity with a primary aim of preventing increased BMI. A secondary analysis of data assessed the impact of PAAC on academic achievement using the Weschler Individual Achievement Test-II and significant improvements were shown for reading, math and spelling in students who participated in PAAC. Based on the results from PAAC, an adequately powered trial will be conducted to assess differences in academic achievement between intervention and control schools called, &#8220;Academic Achievement and Physical Activity Across the Curriculum (A&#8201;+&#8201;PAAC).&#8221; Methods/design Seventeen elementary schools were cluster randomized to A&#8201;+&#8201;PAAC or control for a 3-year trial. Classroom teachers were trained to deliver academic instruction through moderate-to-vigorous physical activity with a target of 100+ minutes of A&#8201;+&#8201;PAAC activities per week. The primary outcome measure is academic achievement measured by the Weschler Individual Achievement Test-III, which was administered at baseline (Fall 2011) and will be repeated in the spring of each year by assessors blinded to condition. Potential mediators of any association between A&#8201;+&#8201;PAAC and academic achievement will be examined on the same schedule and include changes in cognitive function, cardiovascular fitness, daily physical activity, BMI, and attention-to-task. An extensive process analysis will be conducted to document the fidelity of the intervention. School and student recruitment/randomization, teacher training, and baseline testing for A&#8201;+&#8201;PAAC have been completed. Nine schools were randomized to the intervention and 8 to control. A random sample of students in each school, stratified by gender and grade (A&#8201;+&#8201;PAAC&#8201;=&#8201;370, Control&#8201;=&#8201;317), was selected for outcome assessments from those who provided parental consent/child assent. Baseline data by intervention group are presented. Discussion If successful, the A&#8201;+&#8201;PAAC approach could be easily and inexpensively scaled and disseminated across elementary schools to improve both educational quality and health. Funding source: R01- DK85317. Trial registration: US NIH Clinical Trials, http://NCT01699295.Peer Reviewe

    CD133+ adult human retinal cells remain undifferentiated in Leukaemia Inhibitory Factor (LIF)

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>CD133 is a cell surface marker of haematopoietic stem and progenitor cells. Leukaemia inhibitory factor (LIF), sustains proliferation and not differentiation of embryonic stem cells. We used CD133 to purify adult human retinal cells and aimed to determine what effect LIF had on these cultures and whether they still had the ability to generate neurospheres.</p> <p>Methods</p> <p>Retinal cell suspensions were derived from adult human post-mortem tissue with ethical approval. With magnetic automated cell sorting (MACS) CD133<sup>+ </sup>retinal cells were enriched from post mortem adult human retina. CD133<sup>+ </sup>retinal cell phenotype was analysed by flow cytometry and cultured cells were observed for proliferative capacity, neuropshere generation and differentiation with or without LIF supplementation.</p> <p>Results</p> <p>We demonstrated purification (to 95%) of CD133<sup>+ </sup>cells from adult human postmortem retina. Proliferating cells were identified through BrdU incorporation and expression of the proliferation markers Ki67 and Cyclin D1. CD133<sup>+ </sup>retinal cells differentiated whilst forming neurospheres containing appropriate lineage markers including glia, neurons and photoreceptors. LIF maintained CD133<sup>+ </sup>retinal cells in a proliferative and relatively undifferentiated state (Ki67, Cyclin D1 expression) without significant neurosphere generation. Differentiation whilst forming neurospheres was re-established on LIF withdrawal.</p> <p>Conclusion</p> <p>These data support the evidence that CD133 expression characterises a population of cells within the resident adult human retina which have progenitor cell properties and that their turnover and differentiation is influenced by LIF. This may explain differences in retinal responses observed following disease or injury.</p

    Emergency medicine services: Interprofessional care trends

    No full text
    To understand trends in emergency medicine and interprofessional roles in delivering this care, we analyzed a 10-year period (1995-2004) by provider, patient characteristics, and diagnoses. The focus was on how doctors, physician assistants (PAs) and nurse practitioners (NPs) share emergency medicine visits. The National Hospital Ambulatory Medical Care Survey of over 1 billion weighted emergency room visits for 1995 to 2004 was analyzed. The majority of patients were female (53.2%); the mean age of all patients was 35.3 years old. By 2004, physicians were the provider of record for emergency visits at 92.6%, with PAs at 5.7% and NPs at 1.7%. Emergency visits increased for all three providers over the ten years with PA growth doubling during this same period. Medications were prescribed for three-quarters of the visits and were consistent in the mean number of prescriptions written across the three prescribers. No significant differences emerged when urban and rural settings were compared. Expansion of the roles and interprofessional care provided by NPs and PAs include increasing acceptance, clarification of legal and regulatory aspects of practice, shared roles, team approaches to shortages of fully-trained doctors, and the limitation of working hours of physician postgraduate trainees. The US forecast for emergency department visits is expected to outpace the growth of the population and the supply of emergency medicine providers. In view of an increasing emergency medical demand and a continuing shortage of physician personnel, policies are needed for workforce planning to meet the demand

    Information and communication technology to facilitate learning for students in the health professions: Current uses, gaps, and future directions

    Get PDF
    Changes in the U.S. Healthcare System along with the need for institutions of higher education to prepare a work force ready to address the challenges of today and tomorrow have highlighted the need to incorporate technology in its broadest sense as part of the student learning experience. In health professional education, this becomes challenging as programs have traditionally relied on face-to-face instruction along with internship experiences which provide hands on patient care. In addition, learning activities that incorporate higher order critical thinking must be incorporated in order to meet competency based professional expectations as well as expectations in the work place environment. This article will address current technology use in health professional education programs and identify opportunities to incorporate technology to enhance the student learning experiences with emphasis on the critical thinking, communication, and psychomotor skills required of today’s health professional graduate
    corecore