1,235 research outputs found
Neighbourhood, Route and Workplace-Related Environmental Characteristics Predict Adults' Mode of Travel to Work
Commuting provides opportunities for regular physical activity which can reduce the risk of chronic disease. Commuters' mode of travel may be shaped by their environment, but understanding of which specific environmental characteristics are most important and might form targets for intervention is limited. This study investigated associations between mode choice and a range of objectively assessed environmental characteristics.Participants in the Commuting and Health in Cambridge study reported where they lived and worked, their usual mode of travel to work and a variety of socio-demographic characteristics. Using geographic information system (GIS) software, 30 exposure variables were produced capturing characteristics of areas around participants' homes and workplaces and their shortest modelled routes to work. Associations between usual mode of travel to work and personal and environmental characteristics were investigated using multinomial logistic regression.Of the 1124 respondents, 50% reported cycling or walking as their usual mode of travel to work. In adjusted analyses, home-work distance was strongly associated with mode choice, particularly for walking. Lower odds of walking or cycling rather than driving were associated with a less frequent bus service (highest versus lowest tertile: walking OR 0.61 [95% CI 0.20–1.85]; cycling OR 0.43 [95% CI 0.23–0.83]), low street connectivity (OR 0.22, [0.07–0.67]; OR 0.48 [0.26–0.90]) and free car parking at work (OR 0.24 [0.10–0.59]; OR 0.55 [0.32–0.95]). Participants were less likely to cycle if they had access to fewer destinations (leisure facilities, shops and schools) close to work (OR 0.36 [0.21–0.62]) and a railway station further from home (OR 0.53 [0.30–0.93]). Covariates strongly predicted travel mode (pseudo r-squared 0.74).Potentially modifiable environmental characteristics, including workplace car parking, street connectivity and access to public transport, are associated with travel mode choice, and could be addressed as part of transport policy and infrastructural interventions to promote active commuting
Equity impacts of cycling investment in England: a natural experimental study using longitudinally linked individual-level census data.
BACKGROUND: Cycling is beneficial for health and the environment but the evidence on the overall and differential impacts of interventions to promote cycling is limited. Here we assess the equity impacts of funding awarded to support cycling in 18 urban areas between 2005 and 2011. METHODS: We used longitudinally linked 2001 and 2011 census data from 25,747 individuals in the Office for National Statistics Longitudinal Study of England and Wales. Logistic regression was used to assess the impacts of funding on commute mode as the interaction between time and area (intervention/comparison) in individual-level difference-in-difference analyses, adjusting for a range of potential confounding factors. Differential impacts were examined by age, gender, education and area-level deprivation, and uptake and maintenance of cycling were examined separately. RESULTS: Difference-in-difference analyses showed no intervention impact on cycle commuting prevalence in the whole sample (AORÂ =Â 1.08; 95% CI 0.92, 1.26) or among men (AORÂ =Â 0.91; 95% CI 0.76, 1.10) but found an intervention effect among women (AORÂ =Â 1.56; 95% CI 1.16, 2.10). The intervention promoted uptake of cycling commuting in women (AORÂ =Â 2.13; 95% CI 1.56, 2.91) but not men (AORÂ =Â 1.19; 95% CI 0.93, 1.51). Differences in intervention effects by age, education and area-level deprivation were less consistent and more modest in magnitude. CONCLUSIONS: Living in an intervention area was associated with greater uptake of cycle commuting among women but not men. Potential gender differences in the determinants of transport mode choice should be considered in the design and evaluation of future interventions to promote cycling
Assessing the impact of road traffic on cycling for leisure and cycling to work.
BACKGROUND: To explore the relationship between leisure and commuter cycling with objectively measured levels of road traffic and whether any relationship was affected by traffic levels directly outside of home or in local neighbourhood. FINDINGS: We conducted a secondary analysis of data from the UK European Prospective Investigation of Cancer (EPIC) Norfolk cohort in 2009. We used a geographical information system (GIS) and gender specific multivariate models to relate 13 927 participants' reported levels of cycling with an index of road traffic volume (Road Traffic Volume Index Score--RTVIS). RTVIS were calculated around each participants home, using four distance based buffers, (0.5 km, 1 km, 2 km and 3.2 km). Models were adjusted for age, social status, education, car access and deprivation. Both genders had similar decreases in leisure cycling as traffic volumes increased at greater distances from home (OR 0.42, (95% CI 0.32-0.52, p < 0.001) for women and OR 0.41, (95% CI 0.33-0.50, p < 0.001) for men in the highest quartile at 3.2 km). There was no effect of traffic volumes at any distance on commuter cycling. CONCLUSIONS: Traffic volumes appear to have greater impact on leisure cycling than commuter cycling. Future research should investigate the importance of traffic on different types of cycling and include psychosocial correlates.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
What Outcomes are Important for Gout Patients? In-Depth Qualitative Research into the Gout Patient Experience to Determine Optimal Endpoints for Evaluating Therapeutic Interventions
BACKGROUND AND OBJECTIVES: Characterized by sudden onset of severe joint pain, swelling, redness, and tenderness to touch, gout \u27flare ups\u27 have a substantial impact on quality of life (QoL). This research employed a patient-centered approach to explore the symptoms and impacts of gout, and assess the content validity of existing patient-reported outcomes (PROs).
METHODS: Qualitative interviews were conducted with 30 US gout patients (non-tophaceous: n = 20, tophaceous: n = 10) and five expert rheumatologists. Each interview included both concept elicitation (CE) questioning to learn about the patient experience and cognitive debriefing to assess the content validity of three PRO instruments (HAQ-DI, GAQ, and TIQ-20). Nine of the patients provided further real-time qualitative data through a smart phone application. All qualitative data were subject to thematic analysis using Atlas.ti. Two patient advisors and three expert clinicians were engaged as advisors at key stages throughout the research.
RESULTS: Interview and real-time data identified the same core symptoms and proximal impact concepts. Severe pain (typically in joints of extremities) was described as the cardinal symptom, often accompanied by swelling, redness, heat, sensitivity to touch, and stiffness. Domains of QoL impacted included physical functioning, sleep, daily activities, and work. The PRO instruments were generally well-understood by patients, but each included items with questionable relevance to at least some of the sample, dependent on the specific joints affected.
CONCLUSIONS: Gout patients experience severe pain in affected joints, resulting in substantial limitations in physical functioning. Both the HAQ-DI and the TIQ-20 are useful for specific research purposes in the gout population, although modifications are recommended
The Complete Star Formation History of the Universe
The determination of the star-formation history of the Universe is a key goal
of modern cosmology, as it is crucial to our understanding of how structure in
the Universe forms and evolves. A picture has built up over recent years,
piece-by-piece, by observing young stars in distant galaxies at different times
in the past.
These studies indicated that the stellar birthrate peaked some 8 billion
years ago, and then declined by a factor of around ten to its present value.
Here we report on a new study which obtains the complete star formation history
by analysing the fossil record of the stellar populations of 96545 nearby
galaxies. Broadly, our results support those derived from high-redshift
galaxies elsewhere in the Universe. We find, however, that the peak of star
formation was more recent - around 5 billion years ago. Our study also shows
that the bigger the stellar mass of the galaxy, the earlier the stars were
formed. This striking result indicates a very different formation history for
high- and low-mass formation.Comment: Accepted by Nature. Press embargo until publishe
Recommended from our members
Using natural experimental studies to guide public health action: turning the evidence-based medicine paradigm on its head.
Despite smaller effect sizes, interventions delivered at population level to prevent non-communicable diseases generally have greater reach, impact and equity than those delivered to high-risk groups. Nevertheless, how to shift population behaviour patterns in this way remains one of the greatest uncertainties for research and policy. Evidence about behaviour change interventions that are easier to evaluate tends to overshadow that for population-wide and system-wide approaches that generate and sustain healthier behaviours. Population health interventions are often implemented as natural experiments, which makes their evaluation more complex and unpredictable than a typical randomised controlled trial (RCT). We discuss the growing importance of evaluating natural experiments and their distinctive contribution to the evidence for public health policy. We contrast the established evidence-based practice pathway, in which RCTs generate 'definitive' evidence for particular interventions, with a practice-based evidence pathway in which evaluation can help adjust the compass bearing of existing policy. We propose that intervention studies should focus on reducing critical uncertainties, that non-randomised study designs should be embraced rather than tolerated and that a more nuanced approach to appraising the utility of diverse types of evidence is required. The complex evidence needed to guide public health action is not necessarily the same as that which is needed to provide an unbiased effect size estimate. The practice-based evidence pathway is neither inferior nor merely the best available when all else fails. It is often the only way to generate meaningful evidence to address critical questions about investing in population health interventions.DO, JP and NW are supported by the Medical Research Council (Unit Programme numbers MC_UU_12015/6 and MC_UU_12015/1). The paper was initially developed in the course of a visiting appointment as Thought Leader in Residence at the School of Public Health at the University of Sydney, for which the intellectual environment and financial support provided by the Prevention Research Collaboration is gratefully acknowledged. It was further developed under the auspices of the Centre for Diet and Activity Research (CEDAR), a UKCRC Public Health Research Centre of Excellence at the University of Cambridge, for which funding from the British Heart Foundation, Economic and Social Research Council, Medical Research Council, National Institute for Health Research and the Wellcome Trust, under the auspices of the United Kingdom Clinical Research Collaboration, is gratefully acknowledge
Magnitude and Sign Correlations in Heartbeat Fluctuations
We propose an approach for analyzing signals with long-range correlations by
decomposing the signal increment series into magnitude and sign series and
analyzing their scaling properties. We show that signals with identical
long-range correlations can exhibit different time organization for the
magnitude and sign. We find that the magnitude series relates to the nonlinear
properties of the original time series, while the sign series relates to the
linear properties. We apply our approach to the heartbeat interval series and
find that the magnitude series is long-range correlated, while the sign series
is anticorrelated and that both magnitude and sign series may have clinical
applications.Comment: 4 pages,late
Fate of conjugated natural and synthetic steroid estrogens in crude sewage and activated sludge batch studies
This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Environmental Science & Technology, copyright © American Chemical Society after peer review. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/es801952h.Steroids are excreted from the human body in the conjugated form but are present in sewage influent and effluent as the free steroid, the major source of estrogenic activity observed in water courses. The fate of sulfate and glucuronide conjugated steroid estrogens was investigated in batch studies using activated sludge grown on synthetic sewage in a laboratory-scale Husmann simulation and crude sewage from the field. A clear distinction between the fate of sulfate and glucuronide conjugates was observed in both matrices, with sulfated conjugates proving more recalcitrant and glucuronide deconjugation preferential in crude sewage. For each conjugate, the free steroid was observed in the biotic samples. The degree of free steroid formation was dependent on the conjugate moiety, favoring the glucuronide. Subsequent degradation of the free steroid (and sorption to the activated sludge solid phase) was evaluated. Deconjugation followed the first order reaction rate with rate constants for 17α-ethinylestradiol 3-glucuronide, estriol 16α-glucuronide, and estrone 3-glucuronide determined as 0.32, 0.24, and 0.35 h respectively. The activated sludge solid retention time over the range of 3−9 days had 74 to 94% of sulfate conjugates remaining after 8 h. In contrast, a correlation between increasing temperature and decreasing 17α-ethinylestradiol 3-glucuronide concentrations in the activated sludge observed no conjugate present in the AS following 8 h at 22 °C Based on these batch studies and literature excretion profiles, a hypothesis is presented on which steroids and what form (glucuronide, sulfate, or free) will likely enter the sewage treatment plant.EPSR
Simultaneous X-Ray and TeV Gamma-Ray Observations of the TeV Blazar Markarian 421 during February and May 2000
In this paper we present the results of simultaneous observations of the TeV
blazar Markarian 421 (Mrk 421) at X-ray and TeV Gamma-ray energies with the
Rossi X-Ray Timing Explorer (RXTE) and the stereoscopic Cherenkov Telescope
system of the HEGRA (High Energy Gamma Ray Astronomy) experiment, respectively.
The source was monitored from February 2nd to February 16th and from May 3rd to
May 8th, 2000. We discuss in detail the temporal and spectral properties of the
source. Remarkably, the TeV observations of February 7th/8th showed
statistically significant evidence for substantial TeV flux variability on 30
min time scale. We show the results of modeling the data with a time dependent
homogeneous Synchrotron Self-Compton (SSC) model. The X-ray and TeV gamma-ray
emission strengths and energy spectra together with the rapid flux variability
strongly suggest that the emission volume is approaching the observer with a
Doppler factor of 50 or higher. The different flux variability time scales
observed at X-rays and TeV Gamma-rays indicate that a more detailed analysis
will require inhomogeneous models with several emission zones.Comment: Accepted for Publication in ApJ, 21 Pages, 5 Figure
- …