135 research outputs found
Recommended Strategies for Odor Control in Confinement Beef Cattle Operations
Odors coming off a beef feeding operation are generated from three different sources: the feedlot facility, waste storage, and the land where the manure is applied. In some operations, the feedlot facility may also serve as the primary waste storage area. To reduce the total amount of odor generated from a beef feeding operation, odor generation and emission by each of these three sources needs to be reduced
Hypertension burden in Luxembourg: Individual risk factors and geographic variations, 2013 to 2015 European Health Examination Survey
Hypertension is a modifiable risk factor for cardiovascular disease, but it remains the main cause of death in Luxembourg. We aimed to estimate the current prevalence of hypertension, associated risk factors, and its geographic variation in Luxembourg.Cross-sectional, population-based data on 1497 randomly selected Luxembourg residents aged 25 to 64 years were collected as part of the European Health Examination Survey from 2013 to 2015. Hypertension was defined as systolic/diastolic blood pressure ≥140/90 mm Hg, self-report of a physician diagnosis or on antihypertensive medication. Standard and Bayesian regressions were used to examine associations between hypertension and covariates, and also geographic distribution of hypertension across the country.Nearly 31% of Luxembourg residents were hypertensive, and over 70% of those were either unaware of their condition or not adequately controlled. The likelihood of hypertension was lower in men more physically active (odds ratio [95% credible region] 0.6 [0.4, 0.9]) and consuming alcohol daily (0.3 [0.1, 0.8]), and higher in men with a poor health perception (1.6 [1.0, 2.7]) and in women experiencing depressive symptoms (1.8 [1.3, 2.7]). There were geographic variations in hypertension prevalence across cantons and municipalities. The highest odds ratio was observed in the most industrialized region (South-West) (1.2 [0.9, 1.6]) with a positive effect at 90% credible region.In Luxembourg, the vast majority of people with hypertension are either unaware of their condition or not adequately controlled, which constitutes a major, neglected public health challenge. There are geographic variations in hypertension prevalence in Luxembourg, hence the role of individual and regional risk factors along with public health initiatives to reduce disease burden should be considered
Uniform approximation for diffractive contributions to the trace formula in billiard systems
We derive contributions to the trace formula for the spectral density
accounting for the role of diffractive orbits in two-dimensional billiard
systems with corners. This is achieved by using the exact Sommerfeld solution
for the Green function of a wedge. We obtain a uniformly valid formula which
interpolates between formerly separate approaches (the geometrical theory of
diffraction and Gutzwiller's trace formula). It yields excellent numerical
agreement with exact quantum results, also in cases where other methods fail.Comment: LaTeX, 41 pages including 12 PostScript figures, submitted to Phys.
Rev.
Rough droplet model for spherical metal clusters
We study the thermally activated oscillations, or capillary waves, of a
neutral metal cluster within the liquid drop model. These deformations
correspond to a surface roughness which we characterize by a single parameter
. We derive a simple analytic approximate expression determining
as a function of temperature and cluster size. We then estimate the
induced effects on shell structure by means of a periodic orbit analysis and
compare with recent data for shell energy of sodium clusters in the size range
. A small surface roughness \AA~ is seen to
give a reasonable account of the decrease of amplitude of the shell structure
observed in experiment. Moreover -- contrary to usual Jahn-Teller type of
deformations -- roughness correctly reproduces the shape of the shell energy in
the domain of sizes considered in experiment.Comment: 20 pages, 4 figures, important modifications of the presentation, to
appear in Phys. Rev.
Estimating the number of infections and the impact of non-pharmaceutical interventions on COVID-19 in European countries: technical description update
Following the emergence of a novel coronavirus (SARS-CoV-2) and its spread
outside of China, Europe has experienced large epidemics. In response, many
European countries have implemented unprecedented non-pharmaceutical
interventions including case isolation, the closure of schools and
universities, banning of mass gatherings and/or public events, and most
recently, wide-scale social distancing including local and national lockdowns.
In this technical update, we extend a semi-mechanistic Bayesian hierarchical
model that infers the impact of these interventions and estimates the number of
infections over time. Our methods assume that changes in the reproductive
number - a measure of transmission - are an immediate response to these
interventions being implemented rather than broader gradual changes in
behaviour. Our model estimates these changes by calculating backwards from
temporal data on observed to estimate the number of infections and rate of
transmission that occurred several weeks prior, allowing for a probabilistic
time lag between infection and death.
In this update we extend our original model [Flaxman, Mishra, Gandy et al
2020, Report #13, Imperial College London] to include (a) population saturation
effects, (b) prior uncertainty on the infection fatality ratio, (c) a more
balanced prior on intervention effects and (d) partial pooling of the lockdown
intervention covariate. We also (e) included another 3 countries (Greece, the
Netherlands and Portugal).
The model code is available at
https://github.com/ImperialCollegeLondon/covid19model/
We are now reporting the results of our updated model online at
https://mrc-ide.github.io/covid19estimates/
We estimated parameters jointly for all M=14 countries in a single
hierarchical model. Inference is performed in the probabilistic programming
language Stan using an adaptive Hamiltonian Monte Carlo (HMC) sampler
HIV-1 drug-resistance patterns among patients on failing treatment in a large number of European countries
Background: Information about patterns of HIV-1 drug resistance among treatment-exposed patients is crucial for the development of novel effective drugs. Currently no system exists that monitors patterns of resistance in patients failing therapy. Methods: The study included 1,988 HIV-1 sequences from patients experiencing therapy failure collected between 2000 and 2004 in 15 European countries. Genotypic resistance was interpreted using the ANRS algorithm. Phenotypic resistance was predicted using the Virco geno- to phenotype system. Results: 80.7% of the sequences included at least one drug-resistance mutation. Mutations were found for NRTIs (73.5%), NNRTIs (48.5%), and protease inhibitors (35.8%). Ninety percent of sequences with genotypic resistance harbored M184V, M41L, K103N, D67N, and/or T215Y. Among NRTIs, resistance was most frequently predicted for lamivudine. About half of all sequences had reduced susceptibility for NNRTIs. Resistance to most boosted protease inhibitors was found in < 25%. No sequence had resistance to all currently available drugs. Conclusion: Levels of resistance among patients with therapy failure were high. The patterns of resistance reflect resistance to drugs available for a longer time. Fully suppressive regimens can be designed even for the most mutated HIV because boosted protease inhibitors have remained active against most circulating viruses and new drug classes have become available.</p
Bacterial infection profiles in lung cancer patients with febrile neutropenia
<p>Abstract</p> <p>Background</p> <p>The chemotherapy used to treat lung cancer causes febrile neutropenia in 10 to 40% of patients. Although most episodes are of undetermined origin, an infectious etiology can be suspected in 30% of cases. In view of the scarcity of data on lung cancer patients with febrile neutropenia, we performed a retrospective study of the microbiological characteristics of cases recorded in three medical centers in the Picardy region of northern France.</p> <p>Methods</p> <p>We analyzed the medical records of lung cancer patients with neutropenia (neutrophil count < 500/mm<sup>3</sup>) and fever (temperature > 38.3°C).</p> <p>Results</p> <p>The study included 87 lung cancer patients with febrile neutropenia (mean age: 64.2). Two thirds of the patients had metastases and half had poor performance status. Thirty-three of the 87 cases were microbiologically documented. Gram-negative bacteria (mainly enterobacteriaceae from the urinary and digestive tracts) were identified in 59% of these cases. <it>Staphylococcus </it>species (mainly <it>S. aureus</it>) accounted for a high proportion of the identified Gram-positive bacteria. Bacteremia accounted for 60% of the microbiologically documented cases of fever. 23% of the blood cultures were positive. 14% of the infections were probably hospital-acquired and 14% were caused by multidrug-resistant strains. The overall mortality rate at day 30 was 33% and the infection-related mortality rate was 16.1%. Treatment with antibiotics was successful in 82.8% of cases. In a multivariate analysis, predictive factors for treatment failure were age >60 and thrombocytopenia < 20000/mm<sup>3</sup>.</p> <p>Conclusion</p> <p>Gram-negative species were the most frequently identified bacteria in lung cancer patients with febrile neutropenia. Despite the success of antibiotic treatment and a low-risk neutropenic patient group, mortality is high in this particular population.</p
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