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Associations of PM2.5 Constituents and Sources with Hospital Admissions: Analysis of Four Counties in Connecticut and Massachusetts (USA) for Persons ≥ 65 Years of Age
Background: Epidemiological studies have demonstrated associations between short-term exposure to PM2.5 and hospital admissions. The chemical composition of particles varies across locations and time periods. Identifying the most harmful constituents and sources is an important health and regulatory concern. Objectives: We examined pollutant sources for associations with risk of hospital admissions for cardiovascular and respiratory causes. Methods: We obtained PM2.5 filter samples for four counties in Connecticut and Massachusetts and analyzed them for PM2.5 elements. Source apportionment was used to estimate daily PM2.5 contributions from sources (traffic, road dust, oil combustion, and sea salt as well as a regional source representing coal combustion and other sources). Associations between daily PM2.5 constituents and sources and risk of cardiovascular and respiratory hospitalizations for the Medicare population (> 333,000 persons ≥ 65 years of age) were estimated with time-series analyses (August 2000–February 2004). Results: PM2.5 total mass and PM2.5 road dust contribution were associated with cardiovascular hospitalizations, as were the PM2.5 constituents calcium, black carbon, vanadium, and zinc. For respiratory hospitalizations, associations were observed with PM2.5 road dust, and sea salt as well as aluminum, calcium, chlorine, black carbon, nickel, silicon, titanium, and vanadium. Effect estimates were generally robust to adjustment by co-pollutants of other constituents. An interquartile range increase in same-day PM2.5 road dust (1.71 μg/m3) was associated with a 2.11% (95% CI: 1.09, 3.15%) and 3.47% (95% CI: 2.03, 4.94%) increase in cardiovascular and respiratory admissions, respectively. Conclusions: Our results suggest some particle sources and constituents are more harmful than others and that in this Connecticut/Massachusetts region the most harmful particles include black carbon, calcium, and road dust PM2.5. Citation: Bell ML, Ebisu K, Leaderer BP, Gent JF, Lee HJ, Koutrakis P, Wang Y, Dominici F, Peng RD. 2014. Associations of PM2.5 constituents and sources with hospital admissions: analysis of four counties in Connecticut and Massachusetts (USA) for persons ≥ 65 years of age. Environ Health Perspect 122:138–144; http://dx.doi.org/10.1289/ehp.130665
An observational test for correlations between cosmic rays and magnetic fields
We derive the magnitude of fluctuations in total synchrotron intensity in the
Milky Way and M33, from both observations and theory under various assumption
about the relation between cosmic rays and interstellar magnetic fields. Given
the relative magnitude of the fluctuations in the Galactic magnetic field (the
ratio of the rms fluctuations to the mean magnetic field strength) suggested by
Faraday rotation and synchrotron polarization, the observations are
inconsistent with local energy equipartition between cosmic rays and magnetic
fields. Our analysis of relative synchrotron intensity fluctuations indicates
that the distribution of cosmic rays is nearly uniform at the scales of the
order of and exceeding 100\p, in contrast to strong fluctuations in the
interstellar magnetic field at those scales. A conservative upper limit on the
ratio of the the fluctuation magnitude in the cosmic ray number density to its
mean value is 0.2--0.4 at scales of order 100\,pc. Our results are consistent
with a mild anticorrelation between cosmic-ray and magnetic energy densities at
these scales, in both the Milky Way and M33. Energy equipartition between
cosmic rays and magnetic fields may still hold, but at scales exceeding 1\,kpc.
Therefore, we suggest that equipartition estimates be applied to the observed
synchrotron intensity smoothed to a linear scale of kiloparsec order (in spiral
galaxies) to obtain the cosmic ray distribution and a large-scale magnetic
field. Then the resulting cosmic ray distribution can be used to derive the
fluctuating magnetic field strength from the data at the original resolution.
The resulting random magnetic field is likely to be significantly stronger than
existing estimates.Comment: submitted to MNRA
Assessment of habitat and survey criteria for the great crested newt (Triturus cristatus) in Scotland: a case study on a translocated population
The great crested newt Triturus cristatus has declined across its range due to habitat loss, motivating research into biotic and abiotic species determinants. However, research has focused on populations in England and mainland Europe. We examined habitat and survey criteria for great crested newts in Scotland, with focus on a large, translocated population. Adult counts throughout the breeding season were obtained annually using torchlight surveys, and Habitat Suitability Index (HSI) assessed at created ponds (N = 24) in 2006 (immediately post-translocation) and 2015 (9 years post-translocation). In 2006, ‘best case’ HSI scores were calculated to predict habitat suitability should great crested newts have unrestricted access to terrestrial habitat. Abiotic criteria included in and omitted from current great crested newt survey guidelines were assessed using data recorded in 2015. Some ponds had improved HSI scores in 2015, but overall failure to meet predicted scores suggests management is needed to improve habitat suitability. Great crested newt activity was positively associated with moon visibility and phase, air temperature, and pH, but negatively correlated with water clarity. Importantly, our results indicate there are abiotic determinants specific to Scottish great crested newts. Principally, survey temperature thresholds should be lowered to enable accurate census of Scottish populations
BioEarth: Envisioning and developing a new regional earth system model to inform natural and agricultural resource management
Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign
Abstract: In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting supermassive black hole of mass ∼6.5 × 109 M ⊙. The EHTC also partnered with several international facilities in space and on the ground, to arrange an extensive, quasi-simultaneous multi-wavelength campaign. This Letter presents the results and analysis of this campaign, as well as the multi-wavelength data as a legacy data repository. We captured M87 in a historically low state, and the core flux dominates over HST-1 at high energies, making it possible to combine core flux constraints with the more spatially precise very long baseline interferometry data. We present the most complete simultaneous multi-wavelength spectrum of the active nucleus to date, and discuss the complexity and caveats of combining data from different spatial scales into one broadband spectrum. We apply two heuristic, isotropic leptonic single-zone models to provide insight into the basic source properties, but conclude that a structured jet is necessary to explain M87’s spectrum. We can exclude that the simultaneous γ-ray emission is produced via inverse Compton emission in the same region producing the EHT mm-band emission, and further conclude that the γ-rays can only be produced in the inner jets (inward of HST-1) if there are strongly particle-dominated regions. Direct synchrotron emission from accelerated protons and secondaries cannot yet be excluded
Anaesthesia and sleep
The mechanisms regulating the control of consciousness in both spontaneous sleep–wake behaviour and general anaesthesia remain poorly understood and are a fundamental question in neuroscience. The last 30 years have identified numerous molecular substrates and more recently important monoaminergic neuronal substrates. Future work now needs to concentrate on elucidating the convergence of these neuronal circuits to build a unifying mechanism of consciousness control
Improving quality of life for older people in the community : findings from a local Partnerships for Older People Project innovation and evaluation
Copyright Cambridge University PressPartnerships for Older People Projects (POPP) was a national initiative in England aimed at improving health, well-being and quality of life (QoL) for older people by developing local services. This development paper reports the key findings of a local evaluation in relation to quality of life, well-being and health-related QoL to provide practical understanding at the local level about what this means in relation to the schemes delivered.Peer reviewe
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