60 research outputs found
Fluctuations in the current and energy densities around a magnetic flux carrying cosmic string
We calculate the fluctuations in the current and energy densities for the
case of a quantized, minimally coupled, massless, complex scalar field around a
straight and infinitesimally thin cosmic string carrying magnetic flux. At zero
temperature, we evaluate the fluctuations in the current and energy densities
for arbitrary flux and deficit angle. At a finite temperature, we evaluate the
fluctuations in the energy density for the special case wherein the flux is
absent and the deficit angle equals . We find that, quite generically, the
dimensionless ratio of the variance to the mean-squared values of the current
and energy densities are of order unity which suggests that the fluctuations
around cosmic strings can be considered to be large.Comment: RevTeX, 13 Pages, 3 Figure
Recommended from our members
HEALTHCARE-ASSOCIATED INFECTIONS IN PAEDIATRIC AND NEONATAL INTENSIVE CARE UNITS: IMPACT OF UNDERLYING RISK FACTORS AND ANTIMICROBIAL RESISTANCE ON 30-DAY CASE-FATALITY
Objectives.
Our aims were (i) to describe trends in the epidemiology of Healthcare-associated Infections (HAIs) in paediatric/neonatal ICUs and (ii) to evaluate risk factors and impact of Multidrug-Resistance (MDR) in children admitted to ICUs.
Design.
Multicentre, retrospective, cohort study
with a nested case-control study conducted between January 2010 and December 2014.
Setting.
Three tertiary-care paediatric hospitals in Italy and Brazil with a total of 97 ICU beds.
Patients.
Inclusion criteria were (i) admission to ICU during the study period (ii) age at onset <18 years and (iii) microbiologically-confirmed HAI.
Results.
538 HAIs in 454 children were included. 93.3% of patients had comorbidities. Bloodstream infections (BSIs) were the leading pattern (45.4%). The cumulative incidence of HAI was 3.6/100 ICU-admission and the crude 30-day fatality rate was 5.7/1,000-admission. The most frequently
isolated pathogens were Enterobacteriaceae, followed by
Pseudomonas aeruginosa and Staphylococcus aureus.44% of isolates were MDR. Two multivariate logistic regressions were performed. Factors independently associated with an MDR
-HAI were Country, previous antibiotics, transplantation, major surgery, and colonisation by an MDR strain. Factors independently associated with 30-day case-fatality were Country, previous transplantation, fungal infection, BSI, LRTI, and infection caused by MDR strains.
Conclusions.
Infection control and prevention should be a primary focus to limit the spread of MDR strains and improve the outcome of hospitalised patients. Targeted surveillance programmes
collecting neonatal and paediatric HAI/BSI data and outcomes would allow global benchmarking between centres. The next step is to identify simple methods to monitor key HAIs and integrate these into affordable intervention programmes
Dados agronômicos de seis genótipos de sorgo (Sorghum bicolor (L.) Moench) para a produção de silagem.
Foram utilizados seis genótipos de sorgo (Sorghum bicolor (L) Moench) de porte alto e colmo seco, colhidos no estádio de grão leitoso/pastoso, com o objetivo de avaliar a altura média das plantas, número de plantas por hectare, proporção panícula/folha/ colmo, dados de produção de matéria verde, matéria seca e matéria seca digestível por hectare. Os híbridos 1 e 2 são as testemunhas comerciais (BRS610 e VOLUMAX, respectivamente), enquanto que os outros quatro são novos materiais desenvolvidos pela EMBRAPA Milho e Sorgo. Utilizou-se o teste SNK para comparação entre médias, com um delineamento experimental inteiramente ao acaso. Houve grande variação no número de plantas por hectare nos genótipos avaliados. Eles não apresentaram diferença estatística na produção de Matéria Verde/hectare. Os híbridos apresentaram correlação positiva entre produção de MS/ha e altura das plantas [r= 0,52 (p= 0,05)]. O híbrido 2 apresentou maior produção de Matéria Seca e Matéria Seca Digestível/ha. Não houve diferença estatística nas proporções de panícula/folha/colmo, com valores que oscilaram de 42,61 a 55,14; 20,75 a 25.73 e 22,85 a 32,75% na MS, respectivamente
Electron reconstruction and identification efficiency measurements with the ATLAS detector using the 2011 LHC proton–proton collision data
Many of the interesting physics processes to be measured at the LHC have a signature involving one or more isolated electrons. The electron reconstruction and identification efficiencies of the ATLAS detector at the LHC have been evaluated using proton–proton collision data collected in 2011 at s√=7 TeV and corresponding to an integrated luminosity of 4.7 fb −1. Tag-and-probe methods using events with leptonic decays of W and Z bosons and J/ψ mesons are employed to benchmark these performance parameters. The combination of all measurements results in identification efficiencies determined with an accuracy at the few per mil level for electron transverse energy greater than 30 GeV
Electronic structure and magnetic properties of selected lanthanide and actinide intermetallic Laves-phase alloys
The electronic structure and magnetic properties of some yttrium and uranium Laves-phase pseudobinary alloys with 3d elements have been calculated. The calculations were done by simulating the electronic structure of the alloy by that of an ordered compound with the same stoichiometry. In general a good agreement between the experimental and theoretical magnetic moment was found, indicating that the spurious long-range order of the calculations is of minor importance. A comparison between the present supercell cluster approach and the virtual-crystal approximation for the electronic structure and cohesive properties is presented for Y(Fe0.75Co0.25)2 and U(Fe0.5Ni0.5)2
- …