190 research outputs found

    Central adiposity and the propensity for rehearsal in children.

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    Background: There is increasing evidence that continuous activation of the hypothalamic-pituitary adrenal axis and the central sympathetic nervous system contributes to the pathogenesis of central adiposity via increased psychological stress. The purpose of this study was to examine the link between central adiposity and the propensity for Chinese children to rehearse emotionally upsetting events, a dimension of psychological stress. Additionally, gender differences in this relationship were explored. Methods: Waist circumference, which is a marker of central adiposity and associated risks of developing cardiovascular disease, was measured and the propensity for rehearsal was assessed twice over two consecutive years in Hong Kong Chinese children (n = 194, aged 7–9 years), using a psychometric tool. Results: Children with waist circumference indicative of a risk of cardiovascular disease displayed higher rehearsal scores than children categorized as “not at risk”, as did boys compared with girls. Our results suggest that central adiposity and the propensity for rehearsal of emotionally upsetting events may be linked in Chinese children. Conclusion: Future prospective studies examining the direction of causality between central adiposity and rehearsal can potentially have valuable clinical implications

    Analysis between Perturb & Observe Controller and Fuzzy Logic Controller for a Photovoltaic System with CUK and SEPIC Converter

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    The power generation is using Photovoltaic (PV) cell is the best alternative developing for fossil fuel since it renewable green power, energy conservation and demand-side management. Solar energy most useful for sustainable development but due to it has a nonlinear current-voltage characteristic. It is difficult to track the maximum power produce by the PV module. This paper presents a comparison between the Single-Ended Primary-Inductor Converter (SEPIC) and CUK converter by using both Fuzzy Logic Controller (FLC) and Perturb & Observe (P&O) methods in maximum power point tracking (MPPT). In this paper, the performance, advantage and disadvantage for both converters and MPPT algorithm are described. A general model of a Photovoltaic system with proposed MPPT controller and converters is implemented in MATLAB/Simulink software. The input parameter of temperature and irradiation level will be under constant and variable level as to prove the system efficiency towards changing conditions. The simulation result will be analyzed in different case studies in order to prove the effectiveness timely response performances, efficiencies of our power of converting over input power of the PV module and the comparison of transient response of voltage ripple of the systems

    Primary recovery of lipase derived from Burkholderia sp. ST8 with aqueous micellar two-phase system

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    The partitioning and recovery of lipase derived from Burkholderia sp. ST8 strain was explored using temperature-induced aqueous micellar two-phase system (AMTPS) composed of single nonionic surfactant. Nonionic surfactant Triton X-114 and Pluronic series (triblock copolymer) were evaluated in terms of their clouding phenomenon (cloud-point temperature) and the performance of the lipase partitioning in these AMTPSs. Pluronic L81 showed the most optimum partition efficiency for the recovery of lipase to the micellar phase of the AMTPS. Based on the AMTPS which consisted of 24 (w/w) Pluronic L81 and 0.5 (w/w) potassium chloride (KCl), the selectivity of lipase partitioned to bottom phase has been enhanced to 0.035 and the lipase was purified 7.2 fold. Furthermore, the lipase from the micellar phase was consecutively extracted to a new aqueous solution, with an aim of removing the surfactant from the purified lipase. It was attained by replacing the aqueous top phase from the primary recovery of AMTPS with a new potassium thiocyanate (KSCN) solution. The lipase was then recovered in the newly formed bottom aqueous phase which culminated in the yield of 89 and partition coefficients of 0.34 and 4.50 for lipase and surfactant, respectively. AMTPS offers a convenient and efficient method for the primary recovery of lipase with low cost, large loading capacity and the potential of linear scale up. © 2011 Elsevier Ltd. All rights reserved

    Dependence of direct detection signals on the WIMP velocity distribution

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    The signals expected in WIMP direct detection experiments depend on the ultra-local dark matter distribution. Observations probe the local density, circular speed and escape speed, while simulations find velocity distributions that deviate significantly from the standard Maxwellian distribution. We calculate the energy, time and direction dependence of the event rate for a range of velocity distributions motivated by recent observations and simulations, and also investigate the uncertainty in the determination of WIMP parameters. The dominant uncertainties are the systematic error in the local circular speed and whether or not the MW has a high density dark disc. In both cases there are substantial changes in the mean differential event rate and the annual modulation signal, and hence exclusion limits and determinations of the WIMP mass. The uncertainty in the shape of the halo velocity distribution is less important, however it leads to a 5% systematic error in the WIMP mass. The detailed direction dependence of the event rate is sensitive to the velocity distribution. However the numbers of events required to detect anisotropy and confirm the median recoil direction do not change substantially.Comment: 21 pages, 7 figures, v2 version to appear in JCAP, minor change

    Dark Matter Direct Detection Signals inferred from a Cosmological N-body Simulation with Baryons

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    We extract at redshift z=0 a Milky Way sized object including gas, stars and dark matter (DM) from a recent, high-resolution cosmological N-body simulation with baryons. Its resolution is sufficient to witness the formation of a rotating disk and bulge at the center of the halo potential. The phase-space structure of the central galactic halo reveals the presence of a dark disk component, that is co-rotating with the stellar disk. At the Earth's location, it contributes to around 25% of the total DM local density, whose value is rho_DM ~ 0.37 GeV/cm^3. The velocity distributions also show strong deviations from pure Gaussian and Maxwellian distributions, with a sharper drop of the high velocity tail. We give a detailed study of the impact of these features on the predictions for DM signals in direct detection experiments. In particular, the question of whether the modulation signal observed by DAMA is or is not excluded by limits set by other experiments (CDMS, XENON and CRESST...) is re-analyzed and compared to the case of a standard Maxwellian halo, in both the elastic and the inelastic scattering scenarios. We find that the compatibility between DAMA and the other experiments is improved. In the elastic scenario, the DAMA modulation signal is slightly enhanced in the so-called channeling region, as a result of several effects. For the inelastic scenario, the improvement of the fit is mainly attributable to the departure from a Maxwellian distribution at high velocity.Comment: 39 page

    Simulated Milky Way analogues: implications for dark matter direct searches

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    We study the implications of galaxy formation on dark matter direct detection using high resolution hydrodynamic simulations of Milky Way-like galaxies simulated within the eagle and apostle projects. We identify MilkyWay analogues that satisfy observational constraints on the Milky Way rotation curve and total stellar mass. We then extract the dark matter density and velocity distribution in the Solar neighbourhood for this set of Milky Way analogues, and use them to analyse the results of current direct detection experiments. For most Milky Way analogues, the event rates in direct detection experiments obtained from the best _t Maxwellian distribution (with peak speed of 223 { 289 km=s) are similar to those obtained directly from the simulations. As a consequence, the allowed regions and exclusion limits set by direct detection experiments in the dark matter mass and spin-independent cross section plane shift by a few GeV compared to the Standard Halo Model, at low dark matter masses. For each dark matter mass, the halo-to-halo variation of the local dark matter density results in an overall shift of the allowed regions and exclusion limits for the cross section. However, the compatibility of the possible hints for a dark matter signal from DAMA and CDMS-Si and null results from LUX and SuperCDMS is not improved

    An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics

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    For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types

    Genetic determinants of heel bone properties: genome-wide association meta-analysis and replication in the GEFOS/GENOMOS consortium

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    Quantitative ultrasound of the heel captures heel bone properties that independently predict fracture risk and, with bone mineral density (BMD) assessed by X-ray (DXA), may be convenient alternatives for evaluating osteoporosis and fracture risk. We performed a meta-analysis of genome-wide association (GWA) studies to assess the genetic determinants of heel broadband ultrasound attenuation (BUA; n = 14 260), velocity of sound (VOS; n = 15 514) and BMD (n = 4566) in 13 discovery cohorts. Independent replication involved seven cohorts with GWA data (in silico n = 11 452) and new genotyping in 15 cohorts (de novo n = 24 902). In combined random effects, meta-analysis of the discovery and replication cohorts, nine single nucleotide polymorphisms (SNPs) had genome-wide significant (P < 5 × 10(-8)) associations with heel bone properties. Alongside SNPs within or near previously identified osteoporosis susceptibility genes including ESR1 (6q25.1: rs4869739, rs3020331, rs2982552), SPTBN1 (2p16.2: rs11898505), RSPO3 (6q22.33: rs7741021), WNT16 (7q31.31: rs2908007), DKK1 (10q21.1: rs7902708) and GPATCH1 (19q13.11: rs10416265), we identified a new locus on chromosome 11q14.2 (rs597319 close to TMEM135, a gene recently linked to osteoblastogenesis and longevity) significantly associated with both BUA and VOS (P < 8.23 × 10(-14)). In meta-analyses involving 25 cohorts with up to 14 985 fracture cases, six of 10 SNPs associated with heel bone properties at P < 5 × 10(-6) also had the expected direction of association with any fracture (P < 0.05), including three SNPs with P < 0.005: 6q22.33 (rs7741021), 7q31.31 (rs2908007) and 10q21.1 (rs7902708). In conclusion, this GWA study reveals the effect of several genes common to central DXA-derived BMD and heel ultrasound/DXA measures and points to a new genetic locus with potential implications for better understanding of osteoporosis pathophysiology

    Tailored design of graphitic biochar for high-efficiency and chemical-free microwave-assisted removal of refractory organic contaminants

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    Energy-saving, chemical-free, and high-efficiency microwave (MW)-assisted water treatment can be greatly facilitated via tailored design of an economical, sustainable, and ‘green’ carbonaceous catalyst. In this study, various biochars (BC) were pyrolyzed from two lignocellulosic waste biomasses, oak (O) and apple tree (A), at a high temperature (900 °C) and under different gases (N2 and CO2). The holistic characterization by advanced spectroscopic techniques demonstrated that CO2 pyrolysis of feedstock with more lignin (i.e., oak), produced biochar with increased aromaticity and degree of carbonization. CO2 modification created a hierarchical porous structure, improved surface hydrophilicity, polarity, and acidity, and provided higher densities of near-surface functionalities of the biochar. Without MW irradiation, ABC-900C (1 g L−1) provided the highest adsorption (52.6%, 1 min) of 2,4-dichlorophenoxy acetic acid (2,4-D) ascribed to large specific surface area, high micropore content, appropriate pore size, and abundant active groups. OBC-900C (1 g L−1) enabled significantly increased 2,4-D removal (81.6%, 1 min) under MW irradiation (90 °C) in contrast with an oil bath (55.7%, 90 °C, 1 min) and room temperature (33.9%, 1 min) conditions, due to its highest graphitization degree and medium-developed microporous structure. The MW-induced thermal effect formed “hot spots” on the biochar surface as evidenced by elevated temperature of the bulk solution and lowered energy consumption of the MW reactor in the presence of OBC-900C, compared to those of the other biochars. The scavenging tests suggested that the generation of highly oxidative hydroxyl (•OH), anionic superoxide (O2 •−), and singlet oxygen (1O2) radicals contributed to the removal of 2,4-D. This study has demonstrated that biochar with customized structure and high organic adsorption capacity can act as an effective MW absorber suitable for rapid and improved removal of toxic organics

    Driver Fusions and Their Implications in the Development and Treatment of Human Cancers.

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    Gene fusions represent an important class of somatic alterations in cancer. We systematically investigated fusions in 9,624 tumors across 33 cancer types using multiple fusion calling tools. We identified a total of 25,664 fusions, with a 63% validation rate. Integration of gene expression, copy number, and fusion annotation data revealed that fusions involving oncogenes tend to exhibit increased expression, whereas fusions involving tumor suppressors have the opposite effect. For fusions involving kinases, we found 1,275 with an intact kinase domain, the proportion of which varied significantly across cancer types. Our study suggests that fusions drive the development of 16.5% of cancer cases and function as the sole driver in more than 1% of them. Finally, we identified druggable fusions involving genes such as TMPRSS2, RET, FGFR3, ALK, and ESR1 in 6.0% of cases, and we predicted immunogenic peptides, suggesting that fusions may provide leads for targeted drug and immune therapy
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