Survey of low energy plasma electrons in Saturn's magnetosphere: Voyagers 1 and 2

The low energy plasma electron environment within Saturn's magnetosphere was surveyed by the Plasma Science Experiment (PLS) during the Voyager encounters with Saturn. Over the full energy range of the PLS instrument (10 eV to 6 keV) the electron distribution functions are clearly non-Maxwellian in character; they are composed of a cold (thermal) component with Maxwellian shape and a hot (suprathermal) non-Maxwellian component. A large scale positive radial gradient in electron temperature is observed, increasing from less than 1 eV in the inner magnetosphere to as high as 800 eV in the outer magnetosphere. Three fundamentally different plasma regimes were identified from the measurements: (1) the hot outer magnetosphere, (2) the extended plasma sheet, and (3) the inner plasma torus

Comment on "Are periodic solar wind number density structures formed in the solar corona?" by N. M. Viall et al., 2009, Geophys. Res. Lett., 36, L23102, doi:10.1029/2009GL041191

Location of formation of periodic solar wind number density structures is discussed. Observation of proton and alpha anticorrelation in these structures [Viall et al., 2009] indicates that taking into account that bulk velocity of aplha-particles is higher than that of proton the place of formation for these structures should be located at distance less 0.002 AU from place of observation.Comment: 6 pages, submitted in GR

Effect of a new motorway on social-spatial patterning of road traffic accidents: a retrospective longitudinal natural experimental study

Background: The World Health Organisation reports that road traffic accidents (accidents) could become the seventh leading cause of death globally by 2030. Accidents often occur in spatial clusters and, generally, there are more accidents in less advantaged areas. Infrastructure changes, such as new roads, can affect the locations and magnitude of accident clusters but evidence of impact is lacking. A new 5-mile motorway extension was opened in 2011 in Glasgow, Scotland. Previous research found no impact on the number of accidents but did not consider their spatial location or socio-economic setting. We evaluated impacts on these, both locally and city-wide. Methods: We used STATS19 data covering the period 2008 to 2014 and describing the location and details of all reported accidents involving a personal injury. Poisson-based continuous scan statistics were used to detect spatial clusters of accidents and any change in these over time. Change in the socio-economic distribution of accident cluster locations during the study period was also assessed. Results: In each year accidents were strongly clustered, with statistically significant clusters more likely to occur in socio-economically deprived areas. There was no significant shift in the magnitude or location of accident clusters during motorway construction or following opening, either locally or city-wide. There was also no impact on the socio-economic patterning of accident cluster locations. Conclusions: Although urban infrastructure changes occur constantly, all around the world, this is the first study to evaluate the impact of such changes on road accident clusters. Despite expectations to the contrary from both proponents and opponents of the M74 extension, we found no beneficial or adverse change in the socio-spatial distribution of accidents associated with its construction, opening or operation. Our approach and findings can help inform urban planning internationallyThis study was funded by the NIHR Public Health Research programme (project number 11/3005/07: see http://www.nets.nihr.ac. uk/projects/phr/11300507). This article presents independent research funded by the National Institute for Health Research (NIHR). The views and opinions expressed herein are those of the authors and do not necessarily reflect those of the NIHR PHR programme or the Department of Health. The researchers were independent of the funders; the funders had no role in study design, data collection and analysis, the decision to publish, or the preparation of the manuscript. JO, RM and DO are also funded by the Medical Research Council (MRC) as part of the Neighbourhoods and Communities Programme (MC_UU_12017/8) of the MRC/CSO Social and Public Health Sciences Research Unit and the Physical Activity and Public Health Programme (MC_UU_12015/6) of the MRC Epidemiology Unit

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

Effects of new urban motorway infrastructure on road traffic accidents in the local area: a retrospective longitudinal study in Scotland.

BACKGROUND: The M74 motorway extension, Glasgow, opened in June 2011. One justification for construction was an expectation that it would reduce road traffic accidents (RTAs) on local non-motorway roads. This study evaluated the impact of the extension on the number of RTAs, stratifying by accident severity. METHODS: Data for the period 1997-2014 were extracted from a UK database of reported RTAs involving a personal injury. RTA severity was defined by the level of injury: minor, severe or fatal. RTAs were assigned to (1) the local area surrounding the motorway extension, (2) a comparator area surrounding an existing motorway or (3) a control area elsewhere in the conurbation. Interrupted time-series regression with autoregressive integrated moving average (ARIMA) errors was used to determine longitudinal between-area differences in change in the number of RTAs, which might indicate an intervention effect. RESULTS: Glasgow and surrounding local authorities saw a 50.6% reduction in annual RTAs (n: 5901 to 2914) between 1997 and 2014. In the intervention area, the number of recorded RTAs decreased by 50.7% (n: 758 to 374), and that of fatal/severe RTAs by 57.4% (n: 129 to 55), with similar reductions in the comparator/control areas. The interrupted time-series analysis showed no significant between-area differences in temporal trends. The reduction of pedestrian casualties was attenuated in the intervention area relative to Glasgow and surrounding authorities. CONCLUSIONS: Reduction in RTAs was not associated with the motorway extension. Our findings suggest that in planning future investment, it should not be taken for granted that new road infrastructure alone will reduce RTAs in local areas. Urbanisation is proceeding rapidly worldwide, and evidence of infrastructure changes is lacking; this novel study provides important findings for future developments.This study was funded by the NIHR Public Health Research programme (project number 11/3005/07: see http://www.nets.nihr.ac.uk/projects/phr/11300507). DO is funded by the MRC Medical Research Council (MC_UP_12015/6)

Interplanetary and Geomagnetic Consequences of Interacting CMEs of 13-14 June 2012

We report on the kinematics of two interacting CMEs observed on 13 and 14 June 2012. Both CMEs originated from the same active region NOAA 11504. After their launches which were separated by several hours, they were observed to interact at a distance of 100 Rs from the Sun. The interaction led to a moderate geomagnetic storm at the Earth with Dst index of approximately, -86 nT. The kinematics of the two CMEs is estimated using data from the Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) onboard the Solar Terrestrial Relations Observatory (STEREO). Assuming a head-on collision scenario, we find that the collision is inelastic in nature. Further, the signatures of their interaction are examined using the in situ observations obtained by Wind and the Advance Composition Explorer (ACE) spacecraft. It is also found that this interaction event led to the strongest sudden storm commencement (SSC) (approximately 150 nT) of the present Solar Cycle 24. The SSC was of long duration, approximately 20 hours. The role of interacting CMEs in enhancing the geoeffectiveness is examined.Comment: 17 pages, 5 figures, Accepted in Solar Physics Journa

Accretion of Planetary Material onto Host Stars

Accretion of planetary material onto host stars may occur throughout a star's life. Especially prone to accretion, extrasolar planets in short-period orbits, while relatively rare, constitute a significant fraction of the known population, and these planets are subject to dynamical and atmospheric influences that can drive significant mass loss. Theoretical models frame expectations regarding the rates and extent of this planetary accretion. For instance, tidal interactions between planets and stars may drive complete orbital decay during the main sequence. Many planets that survive their stars' main sequence lifetime will still be engulfed when the host stars become red giant stars. There is some observational evidence supporting these predictions, such as a dearth of close-in planets around fast stellar rotators, which is consistent with tidal spin-up and planet accretion. There remains no clear chemical evidence for pollution of the atmospheres of main sequence or red giant stars by planetary materials, but a wealth of evidence points to active accretion by white dwarfs. In this article, we review the current understanding of accretion of planetary material, from the pre- to the post-main sequence and beyond. The review begins with the astrophysical framework for that process and then considers accretion during various phases of a host star's life, during which the details of accretion vary, and the observational evidence for accretion during these phases.Comment: 18 pages, 5 figures (with some redacted), invited revie

The obesity and inflammatory marker haptoglobin attracts monocytes via interaction with chemokine (C-C motif) receptor 2 (CCR2)

<p>Abstract</p> <p>Background</p> <p>Obesity is a chronic low inflammatory state. In the obesity condition the white adipose tissue (WAT) is massively infiltrated with monocytes/macrophages, and the nature of the signals recruiting these inflammatory cells has yet to be fully elucidated. Haptoglobin (Hp) is an inflammatory marker and its expression is induced in the WAT of obese subjects. In an effort to elucidate the biological significance of Hp presence in the WAT and of its upregulation in obesity we formulated the hypothesis that Hp may serve as a macrophage chemoattractant.</p> <p>Results</p> <p>We demonstrated by chemotaxis assay that Hp is able to attract chemokine (C-C motif) receptor 2 (CCR2)-transfected pre-B lymphocytes and monocytes in a dose-dependent manner. Moreover, Hp-mediated migration of monocytes is impaired by CCR2-specific inhibition or previous cell exposure to monocyte chemoattractant protein 1 (MCP1) (also known as CCR2 ligand or chemokine (C-C motif) ligand 2 (CCL2)). Downstream effects of Hp/CCR2 interaction were also investigated: flow cytometry proved that monocytes treated with Hp show reduced CCR2 expression on their surface; Hp interaction induces calcium release that is reduced upon pretreatment with CCR2 antagonist; extracellular signal-regulated kinase (ERK)1/2, a signal transducer activated by CCR2, is phosphorylated following Hp treatment and this phosphorylation is reduced when cells are pretreated with a specific CCR2 inhibitor. Consistently, blocking the ERK1/2 pathway with U0126, the selective inhibitor of the ERK upstream mitogen-activated protein (MAP)-ERK kinase (MEK), results in a dramatic reduction (by almost 100%) of the capability of Hp to induce monocyte migration.</p> <p>Conclusions</p> <p>Our data show that Hp is a novel monocyte chemoattractant and that its chemotactic potential is mediated, at least in part. by its interaction with CCR2.</p