1,155 research outputs found

    Imprints of dynamical dark energy on weak-lensing measurements

    Full text link
    We show that simple models of scalar-field dark energy leave a generic enhancement in the weak-lensing power spectrum when compared to the LCDM prediction. In particular, we calculate the linear-scale enhancement in the convergence (or cosmic-shear) power spectrum for two best-fit models of scalar-field dark energy, namely, the Ratra-Peebles and SUGRA-type quintessence. Our calculations are based on linear perturbation theory, using gauge-invariant variables with carefully defined adiabatic initial conditions. We find that geometric effects enhance the lensing power spectrum on a broad range of scales, whilst the clustering of dark energy gives rise to additional power on large scales. The dark-energy power spectrum for these models are also explicitly obtained. On degree scales, the total enhancement may be as large as 30-40% for sources at redshift ~1. We argue that there are realistic prospects for detecting such an enhancement using the next generation of large telescopes.Comment: 10 pages, 8 figures, replacement matches version published in MNRA

    Pharmacological Inhibition of Soluble Epoxide Hydrolase Ameliorates Diet-Induced Metabolic Syndrome in Rats

    Get PDF
    The signs of metabolic syndrome following chronic excessive macronutrient intake include body weight gain, excess visceral adipose deposition, hyperglycaemia, glucose and insulin intolerances, hypertension, dyslipidaemia, endothelial damage, cardiovascular hypertrophy, inflammation, ventricular contractile dysfunction, fibrosis, and fatty liver disease. Recent studies show increased activity of soluble epoxide hydrolase (sEH) during obesity and metabolic dysfunction. We have tested whether sEH inhibition has therapeutic potential in a rat model of diet-induced metabolic syndrome. In these high-carbohydrate, high-fat-fed rats, chronic oral treatment with trans-4-[4-(3-adamantan-1-ylureido)-cyclohexyloxy]-benzoic acid (t-AUCB), a potent sEH inhibitor, alleviated the signs of metabolic syndrome in vivo including glucose, insulin, and lipid abnormalities, changes in pancreatic structure, increased systolic blood pressure, cardiovascular structural and functional abnormalities, and structural and functional changes in the liver. The present study describes the pharmacological responses to this selective sEH inhibitor in rats with the signs of diet-induced metabolic syndrome

    Non-pharmacological interventions for adults with intellectual disabilities and depression

    Get PDF
    Background: Although high rates of depression symptoms are reported in adults with intellectual disabilities (IDs), there is a lack of knowledge about non-pharmacological treatment options for depression in this population. The first research question of this paper is: Which non-pharmacological interventions have been studied in adults with ID and depression? The second research question is: What were the results of these non-pharmacological interventions?. Method: Systematic review of the literature with an electronic search in six databases has been completed with hand searches. Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines have been followed. Selected studies met predefined inclusion criteria. Results: Literature search resulted in 4267 papers of which 15 met the inclusion criteria. Five different types of non-pharmacological interventions have been studied: cognitive behavioural therapy, behavioural therapy, exercise intervention, social problem-solving skills programme and bright light therapy. Conclusion: There are only a few studies of good quality evaluating non-pharmacological interventions for adults with ID and depression. Some of these studies, especially studies on cognitive behavioural therapy, show good results in decreasing depressive symptoms. High-quality randomised controlled trials evaluating non-pharmacological

    Thermal Properties of Graphene, Carbon Nanotubes and Nanostructured Carbon Materials

    Full text link
    Recent years witnessed a rapid growth of interest of scientific and engineering communities to thermal properties of materials. Carbon allotropes and derivatives occupy a unique place in terms of their ability to conduct heat. The room-temperature thermal conductivity of carbon materials span an extraordinary large range - of over five orders of magnitude - from the lowest in amorphous carbons to the highest in graphene and carbon nanotubes. I review thermal and thermoelectric properties of carbon materials focusing on recent results for graphene, carbon nanotubes and nanostructured carbon materials with different degrees of disorder. A special attention is given to the unusual size dependence of heat conduction in two-dimensional crystals and, specifically, in graphene. I also describe prospects of applications of graphene and carbon materials for thermal management of electronics.Comment: Review Paper; 37 manuscript pages; 4 figures and 2 boxe

    An essential role for dNTP homeostasis following CDK-induced replication stress

    Get PDF
    Replication stress is a common feature of cancer cells, and thus a potentially important therapeutic target. Here, we show that cyclindependent kinase (CDK)-induced replication stress, resulting from Wee1 inactivation, is synthetic lethal with mutations disrupting dNTP homeostasis in fission yeast. Wee1 inactivation leads to increased dNTP demand and replication stress through CDK-induced firing of dormant replication origins. Subsequent dNTP depletion leads to inefficient DNA replication, DNA damage and to genome instability. Cells respond to this replication stress by increasing dNTP supply through histone methyltransferase Set2-dependent MBF-induced expression of Cdc22, the catalytic subunit of ribonucleotide reductase (RNR). Disrupting dNTP synthesis following Wee1 inactivation, through abrogating Set2-dependent H3K36 trimethylation or DNA integrity checkpoint inactivation results in critically low dNTP levels, replication collapse and cell death, which can be rescued by increasing dNTP levels. These findings support a ‘dNTP supply and demand’ model in which maintaining dNTP homeostasis is essential to prevent replication catastrophe in response to CDK-induced replication stress

    Empirical validation of a usability inspection method for model-driven Web development

    Full text link
    Web applications should be usable in order to be accepted by users and to improve their success probability. Despite the fact that this requirement has promoted the emergence of several usability evaluation methods, there is a need for empirically validated methods that provide evidence about their effectiveness and that can be properly integrated into early stages of Web development processes. Model-driven Web development processes have grown in popularity over the last few years, and offer a suitable context in which to perform early usability evaluations due to their intrinsic traceability mechanisms. These issues have motivated us to propose a Web Usability Evaluation Process (WUEP) which can be integrated into model-driven Web development processes. This paper presents a family of experiments that we have carried out to empirically validate WUEP. The family of experiments was carried out by 64 participants, including PhD and Master¿s computer science students. The objective of the experiments was to evaluate the participants¿ effectiveness, efficiency, perceived ease of use and perceived satisfaction when using WUEP in comparison to an industrial widely used inspection method: Heuristic Evaluation (HE). The statistical analysis and meta-analysis of the data obtained separately from each experiment indicated that WUEP is more effective and efficient than HE in the detection of usability problems. The evaluators were also more satisfied when applying WUEP, and found it easier to use than HE. Although further experiments must be carried out to strengthen these results, WUEP has proved to be a promising usability inspection method for Web applications which have been developed by using model-driven development processes.The authors would like to thank all the participants in the experiments, along with the usability experts that supported certain tasks of the evaluation design stage, and of which the control group was composed. This research work is funded by the MULTIPLE project (TIN2009-13838) and the FPU program (AP2007-03731) from the Spanish Ministry of Science and Education.Fernández Martínez, A.; Abrahao Gonzales, SM.; Insfrán Pelozo, CE. (2013). Empirical validation of a usability inspection method for model-driven Web development. Journal of Systems and Software. 86(1):161-186. https://doi.org/10.1016/j.jss.2012.07.043S16118686

    Genotypes and Toxin Gene Profiles of Staphylococcus aureus Clinical Isolates from China

    Get PDF
    A total of 108 S. aureus isolates from 16 major hospitals located in 14 different provinces in China were characterized for the profiles of 18 staphylococcal enterotoxin (SE) genes, 3 exfoliatin genes (eta, etb and etd), and the toxic shock syndrome toxin gene (tsst) by PCR. The genomic diversity of each isolate was also evaluated by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and accessory gene regulator (agr) typing. Of these strains, 90.7% (98/108) harbored toxin genes, in which tsst was the most prevalent toxin gene (48.1%), followed by sea (44.4%), sek (42.6%) and seq (40.7%). The see and etb genes were not found in any of the isolates tested. Because of high-frequency transfer of toxin gene-containing mobile genetic elements between S. aureus strains, a total of 47 different toxin gene combinations were detected, including a complete egc cluster in 19 isolates, co-occurrence of sea, sek and seq in 38 strains, and sec and sel together in 11 strains. Genetic typing by PFGE grouped all the strains into 25 clusters based on 80% similarity. MLST revealed 25 sequence types (ST) which were assigned into 16 clonal complexes (CCs) including 2 new singletons. Among these, 11 new and 6 known STs were first reported in the S. aureus strains from China. Overall, the genotyping results showed high genetic diversity of the strains regardless of their geographical distributions, and no strong correlation between genetic background and toxin genotypes of the strains. For genotyping S. aureus, PFGE appears to be more discriminatory than MLST. However, toxin gene typing combined with PFGE or MLST could increase the discriminatory power of genotyping S. aureus strains
    corecore