33 research outputs found

    Anomalous dimensions and phase transitions in superconductors

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    The anomalous scaling in the Ginzburg-Landau model for the superconducting phase transition is studied. It is argued that the negative sign of the η\eta exponent is a consequence of a special singular behavior in momentum space. The negative sign of η\eta comes from the divergence of the critical correlation function at finite distances. This behavior implies the existence of a Lifshitz point in the phase diagram. The anomalous scaling of the vector potential is also discussed. It is shown that the anomalous dimension of the vector potential ηA=4d\eta_A=4-d has important consequences for the critical dynamics in superconductors. The frequency-dependent conductivity is shown to obey the scaling σ(ω)ξz2\sigma(\omega)\sim\xi^{z-2}. The prediction z3.7z\approx 3.7 is obtained from existing Monte Carlo data.Comment: RevTex, 20 pages, no figures; small changes; version accepted in PR

    Clustering Algorithms: Their Application to Gene Expression Data

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    Gene expression data hide vital information required to understand the biological process that takes place in a particular organism in relation to its environment. Deciphering the hidden patterns in gene expression data proffers a prodigious preference to strengthen the understanding of functional genomics. The complexity of biological networks and the volume of genes present increase the challenges of comprehending and interpretation of the resulting mass of data, which consists of millions of measurements; these data also inhibit vagueness, imprecision, and noise. Therefore, the use of clustering techniques is a first step toward addressing these challenges, which is essential in the data mining process to reveal natural structures and iden-tify interesting patterns in the underlying data. The clustering of gene expression data has been proven to be useful in making known the natural structure inherent in gene expression data, understanding gene functions, cellular processes, and subtypes of cells, mining useful information from noisy data, and understanding gene regulation. The other benefit of clustering gene expression data is the identification of homology, which is very important in vaccine design. This review examines the various clustering algorithms applicable to the gene expression data in order to discover and provide useful knowledge of the appropriate clustering technique that will guarantee stability and high degree of accuracy in its analysis procedure

    Impact of clinical phenotypes on management and outcomes in European atrial fibrillation patients: a report from the ESC-EHRA EURObservational Research Programme in AF (EORP-AF) General Long-Term Registry

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    Background: Epidemiological studies in atrial fibrillation (AF) illustrate that clinical complexity increase the risk of major adverse outcomes. We aimed to describe European AF patients\u2019 clinical phenotypes and analyse the differential clinical course. Methods: We performed a hierarchical cluster analysis based on Ward\u2019s Method and Squared Euclidean Distance using 22 clinical binary variables, identifying the optimal number of clusters. We investigated differences in clinical management, use of healthcare resources and outcomes in a cohort of European AF patients from a Europe-wide observational registry. Results: A total of 9363 were available for this analysis. We identified three clusters: Cluster 1 (n = 3634; 38.8%) characterized by older patients and prevalent non-cardiac comorbidities; Cluster 2 (n = 2774; 29.6%) characterized by younger patients with low prevalence of comorbidities; Cluster 3 (n = 2955;31.6%) characterized by patients\u2019 prevalent cardiovascular risk factors/comorbidities. Over a mean follow-up of 22.5 months, Cluster 3 had the highest rate of cardiovascular events, all-cause death, and the composite outcome (combining the previous two) compared to Cluster 1 and Cluster 2 (all P <.001). An adjusted Cox regression showed that compared to Cluster 2, Cluster 3 (hazard ratio (HR) 2.87, 95% confidence interval (CI) 2.27\u20133.62; HR 3.42, 95%CI 2.72\u20134.31; HR 2.79, 95%CI 2.32\u20133.35), and Cluster 1 (HR 1.88, 95%CI 1.48\u20132.38; HR 2.50, 95%CI 1.98\u20133.15; HR 2.09, 95%CI 1.74\u20132.51) reported a higher risk for the three outcomes respectively. Conclusions: In European AF patients, three main clusters were identified, differentiated by differential presence of comorbidities. Both non-cardiac and cardiac comorbidities clusters were found to be associated with an increased risk of major adverse outcomes

    Shear Localization in Dynamic Deformation: Microstructural Evolution

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    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Influence of certain eco-physiological factors on predation efficiency of Gambusia affinis (Baird and Girard) on Culicine mosquito larvae

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    The effect of light, water temperature and pH on the predation efficiency of Gambusia affinis (Baird and Girard) on Culex pipiens L. (Diptera: Culicidae) mosquito larvae was studied under laboratory conditions. Significant predation rate was recorded in light than in darkness for both male and females, despite fish size. The temperature 30°C showed the most favorable degree for predation compared with 25 and 35°C. Also, the predatory efficiency of G. affinis on mosquito larvae was significant at pH 9 than on 7 and 12.  The present results should be taken in consideration in biological control of mosquito larvae

    Using fenugreek seeds powder as a feed additive in rations of Sharabi local cows and its effect on milk production and chemical composition

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    This study was conducted on nine Sharabi dairy cows at same weights (390±35 kg) and production season (second and third) and cows during first month of calving which were chosen from Sharabi cows farm, Al- Rashedia Station, Department of Agricultural Researches, Nineveh. They were divided into three groups. The fenugreek seed powder was used as a feed additives to the basal ration at a level 50 or 100 g./cow /day for 2nd and 3rd groups, respectively, while the1st group was left as a control ration. Cows were fed individually on basal ration according to developing of body weight and milk production during six weeks, milk production and chemical composition were measured. The results indicated that the amount of feed intake was significantly (P≤0.05) increased for 3rd group, also the normal and adjusted milk yield, fat percentage, value of ration /kg normal milk and milk adjusted were increased significantly (P≤0.05), also the cost for production of one kg of milk was reduced mathematically for 2nd and 3rd groups as compared to those in the 1st group. In conclusion, using 100 g of fenugreek seed powder per cow per day had improved milk production and fat percentage of milk for Sharabi cows

    Corticosteroide

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