2,055 research outputs found
Measurement of the production of a W boson in association with a charm quark in pp collisions at âs = 7 TeV with the ATLAS detector
The production of a W boson in association with a single charm quark is studied using 4.6 fbâ1 of pp collision data at sâ = 7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96+0.26â0.30 at Q 2 = 1.9 GeV2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio Ï(W + +cÂŻÂŻ)/Ï(W â + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the sâsÂŻÂŻÂŻ quark asymmetry
The most creative organization in the world? The BBC, 'creativity' and managerial style
The managerial styles of two BBC directors-general, John Birt and Greg Dyke, have often been contrasted but not so far analysed from the perspective of their different views of 'creative management'. This article first addresses the orthodox reading of 'Birtism'; second, it locates Dyke's 'creative' turn in the wider context of fashionable neo-management theory and UK government creative industries policy; third, it details Dyke's drive to change the BBC's culture; and finally, it concludes with some reflections on the uncertainties inherent in managing a creative organisation
emiT: an apparatus to test time reversal invariance in polarized neutron decay
We describe an apparatus used to measure the triple-correlation term (\D
\hat{\sigma}_n\cdot p_e\times p_\nu) in the beta-decay of polarized neutrons.
The \D-coefficient is sensitive to possible violations of time reversal
invariance. The detector has an octagonal symmetry that optimizes
electron-proton coincidence rates and reduces systematic effects. A beam of
longitudinally polarized cold neutrons passes through the detector chamber,
where a small fraction beta-decay. The final-state protons are accelerated and
focused onto arrays of cooled semiconductor diodes, while the coincident
electrons are detected using panels of plastic scintillator. Details regarding
the design and performance of the proton detectors, beta detectors and the
electronics used in the data collection system are presented. The neutron beam
characteristics, the spin-transport magnetic fields, and polarization
measurements are also described.Comment: 15 pages, 13 figure
Dendritic immune cell densities in the central cornea associated with soft contact lens types and lens care solution types: a pilot study
Cutibacterium acnes biofilm forming clinical isolates modify the formation and structure of Staphylococcus aureus biofilms, increasing their susceptibility to antibiotics
Cutibacterium acnes (formally Propionibacterium acnes) is frequently identified within surgical device related infections. It is often co-isolated from infection sites with other opportunistic pathogens. Recent studies have demonstrated that C. acnes is able to form biofilms and when co-cultured with Staphylococcus spp. both inhibitory and stimulatory effects have been reported across several studies. Here, we investigated the biofilm-forming ability of 100 clinical C. acnes isolates from various infection sites in human patients, both deep tissue and superficial, followed by an investigation of how the supernatants of C. acnes cultures influenced the attachment and maturation of S. aureus NCTC 6571 biofilms. All of the C. acnes isolates were able to form biofilms in vitro, although biofilm biomass varied between isolates. Nineteen isolates were weakly adherent, 33 were moderately adherent and the majority (48) showed strong adherence. The presence of C. acnes sterile supernatants reduced the biomass of S. aureus cultures, with a > 90% reduction observed in the presence of several of the C. acnes isolates. We observed that this decrease was not due to C. acnes affecting S. aureus viability, nor due to the presence of propionic acid. Biofilm maturation was however delayed over a 24-hour period as was biofilm surface structure, although initial (up to 8âŻh) surface attachment was not affected. We hypothesis that this defective biofilm maturation is the cause of the observed biomass decrease. In turn, these altered biofilms showed a greater susceptibility to antibiotic treatments. In contrast the presence of C. acnes supernatant in planktonic (defined as a free moving, non-surface attached population within the liquid column) S. aureus cultures increased antibiotic tolerance, via a currently undefined mechanism. This study suggests that complex interactions between C. acnes and other opportunistic pathogens are likely to exist during colonisation and infection events. Further investigation of these interactions may lead to increased treatment options and a better prognosis for patients
Hidrogenionic potential (pH) of the attractant, trap density and control threshold for Ceratitis capitata (Diptera: tephritidae) on Hamlin oranges in SĂŁo Paulo central region, Brazil
This study evaluated the effect of initial pH values of 4.5, 6.5 and 8.5 of the attractant
(protein bait) MilhocinaÂź and borax (sodium borate) in the feld, on the capture of fruit ïŹies in McPhail
traps, using 1, 2, 4 and 8 traps per hectare, in order to estimate control thresholds in a Hamlin orange grove
in the central region of the state of SĂŁo Paulo. The most abundant fruit ïŹy species was Ceratitis capitata,
comprising almost 99% of the fruit ïŹies captured, of which 80% were females. The largest captures of C.
capitata were found in traps baited with MilhocinaÂź and borax at pH 8.5. Captures per trap for the four
densities were similar, indicating that the population can be estimated with one trap per hectare in areas
with high populations. It was found positive relationships between captures of C. capitata and the number
of Hamlin oranges damaged, 2 and 3 weeks after capture. It was obtained equations that correlate captures
and damage levels which can be used to estimate control thresholds. The average loss caused in Hamlin
orange fruits by C. capitata was 2.5 tons per hectare or 7.5% of production.Esta pesquisa teve como objetivos: avaliar o efeito do pH inicial, 4.5; 6.5 e 8.5, do atrativo
proteico MilhocinaÂź e bĂłrax (tetraborato de sĂłdio) na captura de moscas-das-frutas em armadilhas McPhail;
estudar densidades de armadilhas, 1; 2; 4 e 8 por hectare, para estimar nĂveis de controle em laranja cv.
Hamlin, na região central de São Paulo. A espécie predominante, com 99% das moscas-das-frutas capturadas,
foi Ceratitis capitata, sendo 80% de fĂȘmeas. As maiores capturas de C. capitata ocorreram nas armadilhas
com MilhocinaÂź e bĂłrax em pH 8.5. As capturas, nas 4 densidades, foram semelhantes, indicando que a
população pode ser estimada com uma armadilha por hectare em åreas de altas populaçÔes. Houve relaçÔes
positivas entre capturas de C. capitata e o nĂșmero de frutos danificados, 2 e 3 semanas apĂłs a captura. Assim,
foram obtidas equaçÔes que relacionam a captura e o dano, possibilitando estimar nĂveis de controle desse
inseto. As perdas médias causadas por C. capitata em laranja cv. Hamlin chegaram a 2,5 toneladas de frutos
por hectare ou 7,5% da produção.info:eu-repo/semantics/publishedVersio
Affordances, constraints and information flows as âleverage pointsâ in design for sustainable behaviour
Copyright @ 2012 Social Science Electronic PublishingTwo of Donella Meadows' 'leverage points' for intervening in systems (1999) seem particularly pertinent to design for sustainable behaviour, in the sense that designers may have the scope to implement them in (re-)designing everyday products and services. The 'rules of the system' -- interpreted here to refer to affordances and constraints -- and the structure of information flows both offer a range of opportunities for design interventions to in fluence behaviour change, and in this paper, some of the implications and possibilities are discussed with reference to parallel concepts from within design, HCI and relevant areas of psychology
Development, validation, and proof-of-concept implementation of a two-year risk prediction model for undiagnosed atrial fibrillation using common electronic health data (UNAFIED)
Background: Many patients with atrial fibrillation (AF) remain undiagnosed despite availability of interventions to reduce stroke risk. Predictive models to date are limited by data requirements and theoretical usage. We aimed to develop a model for predicting the 2-year probability of AF diagnosis and implement it as proof-of-concept (POC) in a production electronic health record (EHR).
Methods: We used a nested case-control design using data from the Indiana Network for Patient Care. The development cohort came from 2016 to 2017 (outcome period) and 2014 to 2015 (baseline). A separate validation cohort used outcome and baseline periods shifted 2 years before respective development cohort times. Machine learning approaches were used to build predictive model. Patients â„ 18 years, later restricted to age â„ 40 years, with at least two encounters and no AF during baseline, were included. In the 6-week EHR prospective pilot, the model was silently implemented in the production system at a large safety-net urban hospital. Three new and two previous logistic regression models were evaluated using receiver-operating characteristics. Number, characteristics, and CHA2DS2-VASc scores of patients identified by the model in the pilot are presented.
Results: After restricting age to â„ 40 years, 31,474 AF cases (mean age, 71.5 years; female 49%) and 22,078 controls (mean age, 59.5 years; female 61%) comprised the development cohort. A 10-variable model using age, acute heart disease, albumin, body mass index, chronic obstructive pulmonary disease, gender, heart failure, insurance, kidney disease, and shock yielded the best performance (C-statistic, 0.80 [95% CI 0.79-0.80]). The model performed well in the validation cohort (C-statistic, 0.81 [95% CI 0.8-0.81]). In the EHR pilot, 7916/22,272 (35.5%; mean age, 66 years; female 50%) were identified as higher risk for AF; 5582 (70%) had CHA2DS2-VASc score â„ 2.
Conclusions: Using variables commonly available in the EHR, we created a predictive model to identify 2-year risk of developing AF in those previously without diagnosed AF. Successful POC implementation of the model in an EHR provided a practical strategy to identify patients who may benefit from interventions to reduce their stroke risk
Role of Mutant CFTR in Hypersusceptibility of Cystic Fibrosis Patients to Lung Infections
Cystic fibrosis (CF) patients are hypersusceptible to chronic Pseudomonas aeruginosa lung infections. Cultured human airway epithelial cells expressing the ÎF508 allele of the cystic fibrosis transmembrane conductance regulator (CFTR) were defective in uptake of P. aeruginosa compared with cells expressing the wild-type allele. Pseudomonas aeruginosa lipopolysaccharide (LPS)âcore oligosaccharide was identified as the bacterial ligand for epithelial cell ingestion; exogenous oligosaccharide inhibited bacterial ingestion in a neonatal mouse model, resulting in increased amounts of bacteria in the lungs. CFTR may contribute to a host-defense mechanism that is important for clearance of P. aeruginosa from the respiratory tract
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