799,021 research outputs found

    Association between active commuting and incident cardiovascular disease, cancer, and mortality: prospective cohort study

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    Objective: To investigate the association between active commuting and incident cardiovascular disease (CVD), cancer, and all cause mortality. Design: Prospective population based study. Setting: UK Biobank. Participants: 263 450 participants (106 674 (52%) women; mean age 52.6), recruited from 22 sites across the UK. The exposure variable was the mode of transport used (walking, cycling, mixed mode v non-active (car or public transport)) to commute to and from work on a typical day. Main outcome measures: Incident (fatal and non-fatal) CVD and cancer, and deaths from CVD, cancer, or any causes. Results: 2430 participants died (496 were related to CVD and 1126 to cancer) over a median of 5.0 years (interquartile range 4.3-5.5) follow-up. There were 3748 cancer and 1110 CVD events. In maximally adjusted models, commuting by cycle and by mixed mode including cycling were associated with lower risk of all cause mortality (cycling hazard ratio 0.59, 95% confidence interval 0.42 to 0.83, P=0.002; mixed mode cycling 0.76, 0.58 to 1.00, P<0.05), cancer incidence (cycling 0.55, 0.44 to 0.69, P<0.001; mixed mode cycling 0.64, 0.45 to 0.91, P=0.01), and cancer mortality (cycling 0.60, 0.40 to 0.90, P=0.01; mixed mode cycling 0.68, 0.57 to 0.81, P<0.001). Commuting by cycling and walking were associated with a lower risk of CVD incidence (cycling 0.54, 0.33 to 0.88, P=0.01; walking 0.73, 0.54 to 0.99, P=0.04) and CVD mortality (cycling 0.48, 0.25 to 0.92, P=0.03; walking 0.64, 0.45 to 0.91, P=0.01). No statistically significant associations were observed for walking commuting and all cause mortality or cancer outcomes. Mixed mode commuting including walking was not noticeably associated with any of the measured outcomes. Conclusions: Cycle commuting was associated with a lower risk of CVD, cancer, and all cause mortality. Walking commuting was associated with a lower risk of CVD independent of major measured confounding factors. Initiatives to encourage and support active commuting could reduce risk of death and the burden of important chronic conditions

    The effect of thermal cycling on the high-temperature creep behaviour of a single crystal nickel-based superalloy

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    Isothermal and thermal cycling creep behaviours of a single crystal nickel-based superalloy have been studied by means of tensile tests at 1150 °C and 80 MPa. We have demonstrated that thermal cycling creep rates are faster than isothermal creep rates and that lifetimes at high temperatures are shorter for creep tests under thermal cycling conditions. Furthermore, it is shown that thermal cycling creep lifetime increases as the thermal cycle frequency decreases

    Individual, social and physical environmental correlates of 'never' and 'always' cycling to school among 10 to 12 year old children living within a 3.0 km distance from school

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    BACKGROUND: Cycling to school has been identified as an important target for increasing physical activity levels in children. However, knowledge about correlates of cycling to school is scarce as many studies did not make a distinction between walking and cycling to school. Moreover, correlates of cycling to school for those who live within a distance, that in theory would allow cycling to school, stay undiscovered. Therefore, this study examined individual, social and physical environmental correlates of never and always cycling to/from school among 10 to 12 year old Belgian children living within a 3.0 km distance from school. METHODS: 850 parents completed a questionnaire to assess personal, family, behavioral, cognitive, social and physical environmental factors related to the cycling behavior of their children. Parents indicated on a question matrix how many days a week their child (1) walked, (2) cycled, was (3) driven by car or (4) public transport to and from school during fall, winter and spring. Multivariate logistic regression analyses were conducted to examine the correlates. RESULTS: Overall, 39.3% of children never cycled to school and 16.5% of children always cycled to school. Children with high levels of independent mobility and good cycling skills perceived by their parents were more likely to always cycle to school (resp. OR 1.06; 95% CI 1.04-1.15 and OR 1.08; 95% CI 1.01-1.16) and less likely to never cycle to school (resp. OR 0.84; 95% CI 0.78-0.91 and OR 0.77; 95% CI 0.7-0.84). Children with friends who encourage them to cycle to school were more likely to always cycle to school (OR 1.08; 95% CI 1.01-1.15) and less likely to never cycle to school (OR 0.9; 95% CI 0.83-1.0). In addition, children with parents who encourage them to cycle to school were less likely to never cycle to school (OR 0.78; 95% CI 0.7-0.87). Regarding the physical environmental factors, only neighborhood traffic safety was significantly associated with cycling: i.e., children were more likely to always cycle to school if neighborhood traffic was perceived as safe by their parents (OR 1.18; 95% CI 1.07-1.31). CONCLUSION: Individual, social and physical environmental factors were associated with children's cycling behavior to/from school. However, the contribution of the physical environment is limited and highlights the fact that interventions for increasing cycling to school should not focus solely on the physical environment

    Qualitative accounts of urban commuter cycling

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    Purpose ‐ The purpose of this paper is to explore the live experiences of urban commuter cycling (UCC). Design/methodology/approach ‐ In semi-structured interviews, participants described day-to-day experiences of UCC in a single English city. Verbatim transcripts were coded using the themes of time, space, body and human relations, and interpreted through the principles of hermeneutic phenomenology. Findings ‐ The nine participants (seven males, two females) were aged 27 to 54. Each regularly commuted by bicycle at least three times per week for "18 months" to "27 years". Strong influences on commuter cycling included the weather, daily tasks, cycling infrastructure, driver behaviour and the value of cycling for physical and mental well being. The contest for space was central to the UCC experience, with UCCs sensing they lacked respect despite feeling that they were "embodying citizenship" by enacting public policy. Due to their regular negative experiences, many UCCs were now willing to quit cycling and commute by car. Research limitations/implications ‐ Findings are limited to regular commuter cyclists and do little to describe the passage into regular cycling. Practical applications ‐ This paper highlights that cycle promoters and health educators may profit from focusing on road user interactions during the rush hour. Originality/value ‐ This paper addresses the untold day-to-day experiences of UCCs

    Separator for alkaline batteries

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    Separator compositions have been tested as components of three-plate silver-zinc oxide cells in a standard cycling test. Six materials meet imposed requirements, giving cycling performance superior to cellophane

    Evolution of interfacial dislocation network during anisothermal high-temperature creep of a nickel-based superalloy

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    The effect of thermal cycling creep on the dislocation networks at the γ/γ′ interfaces in the MC2 superalloy is investigated. Tensile creep tests were performed under thermal cycling and isothermal conditions at low stress (80 MPa) and high temperature (1150 °C). In these conditions γ′ rafts may dissolve and reprecipitate during thermal cycling creep. The difference between the effects of isothermal and thermal cycling conditions on the γ/γ′ interface dislocation networks, characterized by transmission electron microscopy, is exposed, as well as their evolution during the cycle

    Understanding walking and cycling:summary of key findings and recommendations

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    It is widely recognized that there is a need to increase levels of active and sustainable travel in British urban areas. The Understanding Walking and Cycling (UWAC) project, funded by the EPSRC, has examined the factors influencing everyday travel decisions and proposes a series of policy measures to increase levels of walking and cycling for short trips in urban areas. A wide range of both quantitative and qualitative data were collected in four English towns (Lancaster, Leeds, Leicester and Worcester), including a questionnaire survey, spatial analysis of the built environment, interviews (static and whilst mobile) and detailed ethnographies. Key findings of the research are that whilst attitudes to walking and cycling are mostly positive or neutral, many people who would like to engage in more active travel fail to do so due to a combination of factors. These can be summarised as: Concerns about the physical environment, especially with regard to safety when walking or cycling; The difficulty of fitting walking and cycling into complex household routines (especially with young children); The perception that walking and cycling are in some ways abnormal things to do. It is suggested that policies to increase levels of walking and cycling should focus not only on improving infrastructure (for instance through fully segregated cycle routes along main roads and restriction on vehicle speeds), but also must tackle broader social, economic, cultural and legal factors that currently inhibit walking and cycling. Together, such changes can create an environment in which driving for short trips in urban areas is seen as abnormal and walking or cycling seem the obvious choices. A joint project by by Lancaster University, Oxford Brookes University and the University of Leeds

    Voltage bias induced modification of all oxide Pr0.5Ca0.5MnO3/SrTi0.95Nb.05O3 junctions

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    In this paper we report what happens to a pristine oxide junction Pr0.5Ca0.5MnO3/SrTi0.95Nb.05O3 (PCMO/Nb:STO), when it is subjected to cycling of voltage bias of moderate value ({\pm}4V). It is found that the initial cycling leads to formation of a permanent state of lower resistance where the lower resistance arises predominantly due to development of a shunt across the device film (PCMO). On successive voltage cycling with increasing magnitude, this state transforms into states of successive lower resistance that can be transformed back to the initial stable state on cycling to below a certain bias. A simple model based on p-n junction with shunt has been used to obtain information on the change of the junction on voltage cycling. It has been shown that the observation can be explained if the voltage cycling leads to lowering of barrier at the interface and also reduction in series resistance. It is suggested that this lowering can be related to the migration of oxygen ions and vacancies at the junction region. Cross-sectional imaging of the junction shows formation of permanent filamentary bridges across the thickness of the PCMO after the pristine p-n junction is first taken through a voltage cycle, which would explain appearance of a finite shunt across the p-n junction.Comment: 12 pages,7figure
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