1,220 research outputs found
Compounding Hazards and Intersecting Vulnerabilities: Experiences and Responses to Extreme Heat During COVID-19
Extreme heat is a major threat to human health worldwide. The COVID-19 pandemic, with its complexity and global reach, created unprecedented challenges for public health and highlighted societal vulnerability to hazardous hot weather. In this study, we used data from a three-wave nationally representative survey of 3036 American adults to examine how the COVID-19 pandemic affected extreme heat vulnerability during the summer of 2020. We used mixed effects models to examine the roles of socio-demographic characteristics and pandemic-related factors in the distribution of negative heat effects and experiences across the United States. The survey findings show that over a quarter of the US population experienced heat-related symptoms during the summer of 2020. Mixed effects models demonstrate that among all socio-economic groups, those who were most vulnerable were women, those in low-income households, unemployed or on furlough, and people who identify as Hispanic or Latino or as other non-white census categories (including Asian, American Indian or Alaska Native, Native Hawaiian or other Pacific Islander, and multi-racial US residents). The study findings indicate that millions of people in the US had difficulty coping with or responding to extreme heat because of the direct and indirect effects of the COVID-19 pandemic. Limited access to cooling as well as COVID-19 related social isolation played a major role in adverse heat health effects. Geographically, the South and the West of the US stood out in terms of self-reported negative heat effects. Overall, the study suggests that the intersection of two health hazards—extreme heat and coronavirus SARS-CoV2—amplified existing systemic vulnerabilities and expanded the demographic range of people vulnerable to heat stress
Tumor necrosis factor-alpha inhibition reduces CXCL-8 levels but fails to prevent fibrin generation and does not improve outcome in a rabbit model of endotoxic shock
The effects of a monoclonal antibody (mAb) to tumor necrosis factor-alpha (TNF-alpha) were examined in a rabbit model of endotoxic shock. Intravenous administration of lipopolysaccharide (100 microg/kg/hr) for 6 hours (n = 11) increased TNF-alpha levels. Fibrinogen was partially consumed, and fibrin deposits were seen in kidney and lungs at 24 hours. Mortality at 24 hours was 64%. Levels of interleukin-8 (aka CXCL-8) were notably increased. Mean arterial pressure (MAP) and leukocyte counts decreased, whereas creatinine levels were enhanced. The anti-TNF-alpha mAb (20 mg/kg i.v. bolus + 5 mg/kg/h i.v. for the first 90 minutes) (n = 10) efficiently inhibited the TNF-activity. Rabbits exhibited lower CXCL-8 levels; MAP improved, the decrease in leukocyte counts was partially prevented and creatinine levels were lower, but fibrinogen, fibrin deposits in kidneys and lungs and mortality, 55%, were similar to the LPS group. Rabbits that did not survive exhibited lower fibrinogen levels, more fibrin in kidneys and lungs and higher CXCL-8 and creatinine levels than survivors, while there were no differences in TNF-alpha, MAP and leukocytes. Thus, the inhibition of TNF-alpha, although beneficial through lowering CXCL-8 levels, is not enough to improve the outcome, which could be partly due to the inability to prevent the fibrin deposits formation in kidneys and lungs
Study of the p p -> p p pi+ pi- Reaction in the Low-Energy Tail of the Roper Resonance
Exclusive measurements of the p p -> p p pi+ pi- reaction have been carried
out at Tp = 775 MeV at CELSIUS using the PROMICE/WASA setup. Together with data
obtained at lower energy they point to a dominance of the Roper excitation in
this process. From the observed interference of its decay routes N* -> N sigma
and N* -> Delta pi -> N sigma their energy-dependent relative branching ratio
is determined
The unidentified TeV source (TeVJ2032+4130) and surrounding field: Final HEGRA IACT-System results
The unidentified TeV source in Cygnus is now confirmed by follow-up
observations from 2002 with the HEGRA stereoscopic system of Cherenkov
Telescopes. Using all data (1999 to 2002) we confirm this new source as steady
in flux over the four years of data taking, extended with radius 6.2 arcmin
(+-1.2 arcmin (stat) +-0.9 arcmin (sys)) and exhibiting a hard spectrum with
photon index -1.9. It is located in the direction of the dense OB stellar
association, Cygnus OB2. Its integral flux above energies E>1 TeV amounts to
\~5% of the Crab assuming a Gaussian profile for the intrinsic source
morphology. There is no obvious counterpart at radio, optical nor X-ray
energies, leaving TeVJ2032+4130 presently unidentified. Observational
parameters of this source are updated here and some astrophysical discussion is
provided. Also included are upper limits for a number of other interesting
sources in the FoV, including the famous microquasar Cygnus X-3.Comment: 7 pages, 3 figures. Accepted for publication in Astronomy &
Astrophysic
Observation of strong final-state effects in pi+ production in pp collisions at 400 MeV
Differential cross sections of the reactions and have been measured at MeV by detecting the charged
ejectiles in the angular range . The
deduced total cross sections agree well with those published previously for
neighbouring energies. The invariant mass spectra are observed to be strongly
affected by production and final-state interaction. The data are
well described by Monte Carlo simulations including both these effects. The
ratio of and cross sections also compares
favourably to a recent theoretical prediction which suggests a dominance of
-production in the relative -state.Comment: 17 pages, 5 figure
Higher Partial Waves in p+p->p+p+eta near Threshold
Exclusive measurements of the production of eta mesons in the p+p->p+p+eta
reaction have been carried out at excess energies of 16 and 37 MeV above
threshold. The deviations from phase space are dominated by the proton-proton
final state interaction and this influences particularly the energy
distribution of the eta meson. However, evidence is also presented at the
higher energy for the existence of an anisotropy in the angular distributions
of the eta meson and also of the final proton-proton pair, probably to be
associated with D-waves in this system interfering with the dominant S-wave
term. The sign of the eta angular anisotropy suggests that rho-exchange is
important for this reaction.Comment: 16 pages, LaTeX2e, 3 EPS Figures, Updated version, Accepted for
publication in Phys. Lett.
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