286 research outputs found

    Important Issues in Implementing Global networks

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    Global communication networks are used by multinational companies for instant access to information and communications. Many advantages can be obtained from implementing a global network; however, many challenges exist in designing and implementing a network that encompasses different countries. This article presents some key issues for the design and implementation of a global network

    CALIBRATION OF PRESSURE SENSORS FOR HAND GRIP MEASUREMENT

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    The purpose of this study was to assess the accuracy of grip force sensors. Methods: Several standard weights were used to calibrate the grip sensor in the static condition, The descriptive statistics and linear regression were used to present the accuracy and errors. Results: Results of this study showed a high level of sensing areas linear relationship under static loading. Conclusion: Data from this study showed high accuracy of the pressure sensor. The pressure sensor could te used for hand grip measurement

    Dealloyed Pt_(2)Os nanoparticles for enhanced oxygen reduction reaction in acidic electrolytes

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    Carbon-supported Pt2Os (Pt_(2)Os/C) nanoparticles in 3.55 nm sizes are synthesized from a wet chemical reflux process. Subsequently, the Pt_(2)Os/C undergoes a dealloying treatment in which multiple cyclic voltammetric scans are imposed to dissolve the Os atoms selectively from the surface of the Pt_(2)Os nanoparticles. X-ray diffraction signals from the dealloyed sample (DA–Pt_(2)Os/C) indicate a fcc phase and composition analysis suggests Pt4Os. Line scans from the scanning transmission electron microscope confirm that the surface of Pt_(4)Os is depleted with the Os atoms. This agrees with our quantum mechanics (Density Funtional theory) calculations, which predict for the Pt_(3)Os composition that the surface skin layer is pure Pt. The DA–Pt_(2)Os/C shows impressive electrocatalytic behaviors (0.29 mA μgPt^(−1) in mass activity and 1.03 mA cmPt^(−2) in specific activity) for the oxygen reduction reaction (ORR) in oxygen-saturated 0.1 M aqueous HClO_4 solution, as compared to those of commercially available Pt/C and as-synthesized Pt_(2)Os/C. In stability test, the DA–Pt_(2)Os/C demonstrates a better retention of ORR activities and a smaller loss of electrochemical active surface area. We verify experimentally that a four-electron step is responsible for the ORR process occurring on the DA–Pt_(2)Os/C

    Association of combination antiretroviral therapy with risk of neurological diseases in patients with HIV/AIDS in Taiwan: a nested case-control study

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    Heterogeneous neurocognitive impairment remains an important issue, even in the era of combination antiretroviral therapy (cART), with an incidence ranging from 15% to 65%. Although ART drugs with higher penetration scores to the central nervous system (CNS) show better HIV replication control in the CNS, the association between CNS penetration effectiveness (CPE) scores and neurocognitive impairment remains inconclusive. To explore whether ART exposure is associated with the risk of neurological diseases among patients with HIV/AIDS, this study in Taiwan involved 2,571 patients with neurological diseases and 10,284 matched, randomly selected patients without neurological diseases between 2010 and 2017. A conditional logistic regression model was used in this study. The parameters for ART exposure included ART usage, timing of exposure, cumulative defined daily dose (DDD), adherence, and cumulative CPE score. Incident cases of neurological diseases, including CNS infections, cognitive disorders, vasculopathy, and peripheral neuropathy, were obtained from the National Health Insurance Research Database in Taiwan. Odds ratios (ORs) for the risk of neurological diseases were conducted using a multivariate conditional logistic regression model. Patients with a history of past exposure (OR: 1.68, 95% confidence interval [CI]:1.22–2.32), low cumulative DDDs (< 2,500) (OR: 1.28, 95% CI: 1.15–1.42), low adherence (0 < adherence (ADH) ≤ 0.8) (OR: 1.46, 95% CI: 1.30–1.64), or high cumulative CPE scores (>14) (OR: 1.34, 95% CI: 1.14–1.57) had a high risk of neurological diseases. When stratified by classes of ART drugs, patients with low cumulative DDDs or low adherence had a high risk of neurological diseases, including NRTIs, PIs, NNRTIs, INSTIs, and multi-drug tablets. Subgroup analyses also suggested that patients with low cumulative DDDs or low adherence had a high risk of neurological diseases when they had high cumulative CPE scores. Patients with high cumulative DDDs or medication adherence were protected against neurological diseases only when they had low cumulative CPE scores (≤ 14). Patients may be at risk for neurological diseases when they have low cumulative DDDs, low adherence, or usage with high cumulative CPE scores. Continuous usage and low cumulative CPE scores of ART drugs may benefit neurocognitive health in patients with HIV/AIDS

    Functional characterization of cellulases identified from the cow rumen fungus Neocallimastix patriciarum W5 by transcriptomic and secretomic analyses

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    <p>Abstract</p> <p>Background</p> <p><it>Neocallimastix patriciarum</it> is one of the common anaerobic fungi in the digestive tracts of ruminants that can actively digest cellulosic materials, and its cellulases have great potential for hydrolyzing cellulosic feedstocks. Due to the difficulty in culture and lack of a genome database, it is not easy to gain a global understanding of the glycosyl hydrolases (<it>GHs</it>) produced by this anaerobic fungus.</p> <p>Results</p> <p>We have developed an efficient platform that uses a combination of transcriptomic and proteomic approaches to <it>N. patriciarum </it>to accelerate gene identification, enzyme classification and application in rice straw degradation. By conducting complementary studies of transcriptome (Roche 454 GS and Illumina GA IIx) and secretome (ESI-Trap LC-MS/MS), we identified 219 putative <it>GH </it>contigs and classified them into 25 <it>GH</it> families. The secretome analysis identified four major enzymes involved in rice straw degradation: β-glucosidase, endo-1,4-β-xylanase, xylanase B and Cel48A exoglucanase. From the sequences of assembled contigs, we cloned 19 putative cellulase genes, including the <it>GH1</it>, <it>GH3</it>, <it>GH5</it>, <it>GH6</it>, <it>GH9</it>, <it>GH18</it>, <it>GH43 </it>and <it>GH48 </it>gene families, which were highly expressed in <it>N. patriciarum </it>cultures grown on different feedstocks.</p> <p>Conclusions</p> <p>These <it>GH </it>genes were expressed in Pichia pastoris and/or Saccharomyces cerevisiae for functional characterization. At least five novel cellulases displayed cellulytic activity for glucose production. One β-glucosidase (W5-16143) and one exocellulase (W5-CAT26) showed strong activities and could potentially be developed into commercial enzymes.</p

    Urinary levels of organophosphate flame retardants metabolites in a young population from Southern Taiwan and potential health effects

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    BackgroundOrganophosphate flame retardants (OPFRs) are widely distributed in the environment and their metabolites are observed in urine, but little is known regarding OPFRs in a broad-spectrum young population from newborns to those aged 18 years.ObjectivesInvestigate urinary levels of OPFRs and OPFR metabolites in Taiwanese infants, young children, schoolchildren, and adolescents within the general population.MethodsDifferent age groups of subjects (n=136) were recruited from southern Taiwan to detect 10 OPFR metabolites in urine samples. Associations between urinary OPFRs and their corresponding metabolites and potential health status were also examined.ResultsThe mean level of urinary Σ10 OPFR in this broad-spectrum young population is 2.25 μg/L (standard deviation (SD) of 1.91 μg/L). Σ10 OPFR metabolites in urine are 3.25 ± 2.84, 3.06 ± 2.21, 1.75 ± 1.10, and 2.32 ± 2.29 μg/L in the age groups comprising of newborns, 1-5 year-olds, 6-10 year-olds, and 11-18 year-olds, respectively, and borderline significant differences were found in the different age groups (p=0.125). The OPFR metabolites of TCEP, BCEP, DPHP, TBEP, DBEP, and BDCPP predominate in urine and comprise more than 90% of the total. TBEP was highly correlated with DBEP in this population (r=0.845, p&lt;0.001). The estimated daily intake (EDI) of Σ5OPFRs (TDCPP, TCEP, TBEP, TNBP, and TPHP) was 2,230, 461, 130, and 184 ng/kg bw/day for newborns, 1-5 yr children, 6-10 yr children, and 11-17 yr adolescents, respectively. The EDI of Σ5OPFRs for newborns was 4.83-17.2 times higher than the other age groups. Urinary OPFR metabolites are significantly correlated with birth length and chest circumference in newborns.ConclusionTo our knowledge, this is the first investigation of urinary OPFR metabolite levels in a broad-spectrum young population. There tended to be higher exposure rates in both newborns and pre-schoolers, though little is known about their exposure levels or factors leading to exposure in the young population. Further studies should clarify the exposure levels and factor relationships
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