The neighbourhood physical environment: Relationships with physical activity and depression in adults in the United Kingdom

Background: The impact of neighbourhood physical environments on physical activity and health is widely acknowledged, with much research conducted to identify key factors. Results have been mixed, partly due to inconsistencies in how neighbourhoods are defined. This thesis examines relationships of physical environments with physical activity, and with depression, exploring influence of neighbourhood operationalisation. Method: Physical activity and depression outcomes were derived from a sample drawn from the seventh wave of the Whitehall II study conducted in 2004/5, and depression outcomes were also taken from the 2008 Health Survey for England. Neighbourhoods were operationalised at three levels of administrative geography and as residential postcode-centred GIS software-computed zones. Four main exposure variables were specified: a greenspace measure was constructed from the Generalised Land Use Database; an objective measure of environmental quality was derived from metadata of the Multiple Environmental Deprivation Index, and a subjective one from the 2008 Place Survey; and a walkability measure was constructed using GIS, drawing on several geographical databases. Multivariate logistic regression was used to measure statistical associations between exposures and outcomes, with adjustment for individual-level sociodemographic factors and area-level deprivation, and multilevel modelling was performed to estimate the contribution of neighbourhood characteristics relative to those of individuals to variation in outcomes. Results: Neighbourhood physical environments accounted for a small proportion of variation in all outcomes. Nevertheless, significant associations were found between all exposure variables and physical activity, independently of individual-level sociodemographic factors and area-level deprivation, the direction dependent on outcome specification. Only objectively measured environmental quality was significantly and independently with depression, with lower quality giving higher odds of this outcome. Strengths of associations were not substantively affected by neighbourhood operationalisation. Conclusion: This thesis increases understanding of physical environment attributes relevant to physical activity and depression in a European context and how neighbourhoods in which they are measured may best be defined

A novel walkability index for London predicts walking time in adults

Objective: To develop a novel walkability index for London and test it through measurement of associations between neighbourhood walkability and walking among adults using data from the Whitehall II Study. Background: Physical activity is essential for health; walking is the easiest way to incorporate it into everyday life. Many studies have reported positive associations between neighbourhood walkability and walking but the majority have focused on cities in North America and Australasia. Urban form with respect to street connectivity, residential density and land use mix – common components of walkability indices – is likely to differ in European cities. Methods: A walkability index for the 633 spatially contiguous census area statistics wards of London was constructed, comprising three core dimensions associated with walking behaviours: residential dwelling density, street connectivity and land use mix. Walkability was expressed as quartile scores, with wards scoring 1 being in the bottom 25% in terms of walkability, and those scoring 4 in the top 25%. A neighbourhood walkability score was assigned to each London-dwelling Whitehall II Study participant (2003-04, N=3020, mean +/-SD age=61.0y +/-6.0) as the walkability score of the ward in which their residential postcode fell. Associations between neighbourhood walkability and weekly walking time were measured using multiple logistic regression. Results: After adjustment for individual level factors and area deprivation, people in the most walkable neighbourhoods were significantly more likely to spend ≥6hr/wk (Odds Ratio 1.4; 95%Confidence Interval 1.1-1.9), than those in the least walkable. Conclusions: The walkability index constructed can predict walking time in adults: living in a more walkable neighbourhood is associated with longer weekly walking time. The index may help urban planners identify and design neighbourhoods in London with characteristics that are potentially more supportive of walking and, thereby, promote public health

Development of a novel walkability index for London, United Kingdom: cross-sectional application to the Whitehall II study

BACKGROUND: Physical activity is essential for health; walking is the easiest way to incorporate activity into everyday life. Previous studies report positive associations between neighbourhood walkability and walking but most focused on cities in North America and Australasia. Urban form with respect to street connectivity, residential density and land use mix-common components of walkability indices-differs in European cities. The objective of this study was to develop a walkability index for London and test the index using walking data from the Whitehall II Study.  METHODS: A neighbourhood walkability index for London was constructed, comprising factors associated with walking behaviours: residential dwelling density, street connectivity and land use mix. Three models were produced that differed in the land uses included. Neighbourhoods were operationalised at three levels of administrative geography: (i) 21,140 output areas, (ii) 633 wards and (iii) 33 local authorities. A neighbourhood walkability score was assigned to each London-dwelling Whitehall II Study participant (2003-04, N = 3020, mean ± SD age = 61.0 years ± 6.0) based on residential postcode. The effect of changing the model specification and the units of enumeration on spatial variation in walkability was examined. RESULTS: There was a radial decay in walkability from the centre to the periphery of London. There was high inter-model correlation in walkability scores for any given neighbourhood operationalisation (0.92-0.98), and moderate-high correlation between neighbourhood operationalisations for any given model (0.39-0.70). After adjustment for individual level factors and area deprivation, individuals in the most walkable neighbourhoods operationalised as wards were more likely to walk >6 h/week (OR = 1.4; 95 % CI: 1.1-1.9) than those in the least walkable. CONCLUSIONS: Walkability was associated with walking time in adults. This walkability index could help urban planners identify and design neighbourhoods in London with characteristics more supportive of walking, thereby promoting public health

Surveillance recommendations based on an exploratory analysis of respiratory syncytial virus reports derived from the European Influenza Surveillance System

BACKGROUND: Respiratory syncytial virus (RSV) is an important pathogen that can cause severe illness in infants and young children. In this study, we assessed whether data on RSV collected by the European Influenza Surveillance Scheme (EISS) could be used to build an RSV surveillance system in Europe. METHODS: Influenza and RSV data for the 2002–2003 winter season were analysed for England, France, the Netherlands and Scotland. Data from sentinel physician networks and other sources, mainly hospitals, were collected. Respiratory specimens were tested for influenza and RSV mainly by virus culture and polymerase chain reaction amplification. RESULTS: Data on RSV were entered timely into the EISS database. RSV contributed noticeably to influenza-like illness: in England sentinel RSV detections were common in all age groups, but particularly in young children with 20 (40.8%) of the total number of sentinel swabs testing positive for RSV. Scotland and France also reported the highest percentages of RSV detections in the 0–4 year age group, respectively 10.3% (N = 29) and 12.2% (N = 426). In the Netherlands, RSV was detected in one person aged over 65 years. CONCLUSION: We recommend that respiratory specimens collected in influenza surveillance are also tested systematically for RSV and emphasize the use of both community derived data and data from hospitals for RSV surveillance. RSV data from the EISS have been entered in a timely manner and we consider that the EISS model can be used to develop an RSV surveillance system equivalent to the influenza surveillance in Europe

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

The Effects of Dietary Carotenoid Supplementation and Retinal Carotenoid Accumulation on Vision-Mediated Foraging in the House Finch

BACKGROUND: For many bird species, vision is the primary sensory modality used to locate and assess food items. The health and spectral sensitivities of the avian visual system are influenced by diet-derived carotenoid pigments that accumulate in the retina. Among wild House Finches (Carpodacus mexicanus), we have found that retinal carotenoid accumulation varies significantly among individuals and is related to dietary carotenoid intake. If diet-induced changes in retinal carotenoid accumulation alter spectral sensitivity, then they have the potential to affect visually mediated foraging performance. METHODOLOGY/PRINCIPAL FINDINGS: In two experiments, we measured foraging performance of house finches with dietarily manipulated retinal carotenoid levels. We tested each bird's ability to extract visually contrasting food items from a matrix of inedible distracters under high-contrast (full) and dimmer low-contrast (red-filtered) lighting conditions. In experiment one, zeaxanthin-supplemented birds had significantly increased retinal carotenoid levels, but declined in foraging performance in the high-contrast condition relative to astaxanthin-supplemented birds that showed no change in retinal carotenoid accumulation. In experiments one and two combined, we found that retinal carotenoid concentrations predicted relative foraging performance in the low- vs. high-contrast light conditions in a curvilinear pattern. Performance was positively correlated with retinal carotenoid accumulation among birds with low to medium levels of accumulation (∼0.5-1.5 µg/retina), but declined among birds with very high levels (>2.0 µg/retina). CONCLUSION/SIGNIFICANCE: Our results suggest that carotenoid-mediated spectral filtering enhances color discrimination, but that this improvement is traded off against a reduction in sensitivity that can compromise visual discrimination. Thus, retinal carotenoid levels may be optimized to meet the visual demands of specific behavioral tasks and light environments

Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal