399 research outputs found
The impacts of climate change on sea temperature around the UK and Ireland
What is already happening?
• Sea surface temperature (SST) around the UK generally shows a significant warming trend of around 0.3C per decade over the last 40 years.
• Regional variations exist in this trend with surface warming being greatest across the southern North Sea and least across the north-west of the domain.
• Warm-season (Autumn) near-bottom temperatures have increased significantly across the southern North Sea over the last 30 years, but not across other regions of the domain.
• Compared to 1982–1998, the annual number of marine heatwaves increased around the British Isles by an average of four events per year in the period 2000–2016. Larger increases of up to six additional events per year occurred to the north of the British Isles. Smaller changes occurred to the south of the region
Impact of alcohol use disorder severity on human immunodeficiency virus (HIV) viral suppression and CD4 count in three international cohorts of people with HIV.
Alcohol use has been linked to worse human immunodeficiency virus (HIV) immunologic/virologic outcomes, yet few studies have explored the effects of alcohol use disorder (AUD). This study assessed whether AUD severity is associated with HIV viral suppression and CD4 count in the three cohorts of the Uganda Russia Boston Alcohol Network for Alcohol Research Collaboration on HIV/AIDS (URBAN ARCH) Consortium.
People with HIV (PWH) in Uganda (n = 301), Russia (n = 400), and Boston (n = 251), selected in-part based on their alcohol use, were included in analyses. Logistic and linear regressions were used to assess the cross-sectional associations between AUD severity (number of DSM-5 diagnostic criteria) and (1) HIV viral suppression, and (2) CD4 count (cells/mm <sup>3</sup> ) adjusting for covariates. Analyses were conducted separately by site.
The proportion of females was 51% (Uganda), 34% (Russia), and 33% (Boston); mean age (SD) was 40.7 (9.6), 38.6 (6.3), and 52.1 (10.5), respectively. All participants in Uganda and all but 27% in Russia and 5% in Boston were on antiretroviral therapy. In Uganda, 32% met criteria for AUD, 92% in Russia, and 43% in Boston. The mean (SD) number of AUD criteria was 1.6 (2.4) in Uganda, 5.6 (3.3) in Russia, and 2.4 (3.1) in Boston. Most participants had HIV viral suppression (Uganda 92%, Russia 57%, Boston 87%); median (IQR) CD4 count was 673 (506, 866), 351 (201, 542), and 591 (387, 881), respectively. In adjusted models, there were no associations between AUD severity and HIV viral suppression: adjusted odds ratios (AOR) (95%CI) per 1 additional AUD criterion in Uganda was 1.08 (0.87, 1.33); Russia 0.98 (0.92, 1.04); and Boston 0.95 (0.84, 1.08) or CD4 count: mean difference (95%CI) per 1 additional criterion: 5.78 (-7.47, 19.03), -3.23 (-10.91, 4.44), and -8.18 (-24.72, 8.35), respectively.
In three cohorts of PWH, AUD severity was not associated with HIV viral suppression or CD4 count. PWH with AUD in the current era of antiretroviral therapy can achieve virologic control
First Measurement of Z/gamma* Production in Compton Scattering of Quasi-real Photons
We report the first observation of Z/gamma* production in Compton scattering
of quasi-real photons. This is a subprocess of the reaction e+e- to
e+e-Z/gamma*, where one of the final state electrons is undetected.
Approximately 55 pb-1 of data collected in the year 1997 at an e+e-
centre-of-mass energy of 183 GeV with the OPAL detector at LEP have been
analysed. The Z/gamma* from Compton scattering has been detected in the
hadronic decay channel. Within well defined kinematic bounds, we measure the
product of cross-section and Z/gamma* branching ratio to hadrons to be
(0.9+-0.3+-0.1) pb for events with a hadronic mass larger than 60 GeV,
dominated by (e)eZ production. In the hadronic mass region between 5 GeV and 60
GeV, dominated by (e)egamma* production, this product is found to be
(4.1+-1.6+-0.6) pb. Our results agree with the predictions of two Monte Carlo
event generators, grc4f and PYTHIA.Comment: 18 pages, LaTeX, 5 eps figures included, submitted to Physics Letters
Search for Higgs Bosons in e+e- Collisions at 183 GeV
The data collected by the OPAL experiment at sqrts=183 GeV were used to
search for Higgs bosons which are predicted by the Standard Model and various
extensions, such as general models with two Higgs field doublets and the
Minimal Supersymmetric Standard Model (MSSM). The data correspond to an
integrated luminosity of approximately 54pb-1. None of the searches for neutral
and charged Higgs bosons have revealed an excess of events beyond the expected
background. This negative outcome, in combination with similar results from
searches at lower energies, leads to new limits for the Higgs boson masses and
other model parameters. In particular, the 95% confidence level lower limit for
the mass of the Standard Model Higgs boson is 88.3 GeV. Charged Higgs bosons
can be excluded for masses up to 59.5 GeV. In the MSSM, mh > 70.5 GeV and mA >
72.0 GeV are obtained for tan{beta}>1, no and maximal scalar top mixing and
soft SUSY-breaking masses of 1 TeV. The range 0.8 < tanb < 1.9 is excluded for
minimal scalar top mixing and m{top} < 175 GeV. More general scans of the MSSM
parameter space are also considered.Comment: 49 pages. LaTeX, including 33 eps figures, submitted to European
Physical Journal
A Measurement of the Product Branching Ratio f(b->Lambda_b).BR(Lambda_b->Lambda X) in Z0 Decays
The product branching ratio, f(b->Lambda_b).BR(Lambda_b->Lambda X), where
Lambda_b denotes any weakly-decaying b-baryon, has been measured using the OPAL
detector at LEP. Lambda_b are selected by the presence of energetic Lambda
particles in bottom events tagged by the presence of displaced secondary
vertices. A fit to the momenta of the Lambda particles separates signal from B
meson and fragmentation backgrounds. The measured product branching ratio is
f(b->Lambda_b).BR(Lambda_b->Lambda X) = (2.67+-0.38(stat)+0.67-0.60(sys))%
Combined with a previous OPAL measurement, one obtains
f(b->Lambda_b).BR(Lambda_b->Lambda X) = (3.50+-0.32(stat)+-0.35(sys))%.Comment: 16 pages, LaTeX, 3 eps figs included, submitted to the European
Physical Journal
Measurement of the Michel Parameters in Leptonic Tau Decays
The Michel parameters of the leptonic tau decays are measured using the OPAL
detector at LEP. The Michel parameters are extracted from the energy spectra of
the charged decay leptons and from their energy-energy correlations. A new
method involving a global likelihood fit of Monte Carlo generated events with
complete detector simulation and background treatment has been applied to the
data recorded at center-of-mass energies close to sqrt(s) = M(Z) corresponding
to an integrated luminosity of 155 pb-1 during the years 1990 to 1995. If e-mu
universality is assumed and inferring the tau polarization from neutral current
data, the measured Michel parameters are extracted. Limits on non-standard
coupling constants and on the masses of new gauge bosons are obtained. The
results are in agreement with the V-A prediction of the Standard Model.Comment: 32 pages, LaTeX, 9 eps figures included, submitted to the European
Physical Journal
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