140 research outputs found

    Temporal Variability of Groundwater Chemistry and Relationship with Water-table Fluctuation in the Jianghan Plain, Central China

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    AbstractSamples were collected every month from 39 monitoring wells over a period of 1 year and three months (from Jan 2013 to Mar 2014) in the Jianghan alluvial plain in the middle reaches of the Yangtze river, central China, to evaluate the temporal variability of groundwater composition for As and other constituents. The concentrations of K,Na,Ca,Mg in groundwater generally varied less than 30%, whereas concentrations of the redox-sensitive components (Fe,NH4-N,S and As) varied greater over time. In wells tapping the confined aquifers with depth of 25m, concentrations of groundwater As were much higher and ranged up to760 ±320μg/L seasonally. Higher As concentration were associated with an increasing percentage of As(III) in rainy season and a decrease towards the end of dry season, indicating a reductive mobilization responding to groundwater level fluctuation

    Application of evolution-based uncertainty design on gear

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    The evolution of mechanical parameters, a factor affecting the mechanical reliability, has gathered more attention nowadays. However, studies on time varying uncertainty can hardly be found. A new method based on evolution-based uncertainty design (EBUD) is applied to the design of gear in this paper. Considering the wear evolution over the lifetime, a tooth wear’s time-varying uncertainty model based on the continuous-time model and Ito lemma is established. Drift and volatility functions dependent on the drift rate and volatility rate of rotational speed and torque are used to express the time-varying uncertainty of tooth thickness. The method can predict the reliability and provide an instruction in reliability improving, maintenance and repair of the gear system

    Mutations in a Highly Conserved Motif of nsp1? Protein Attenuate the Innate Immune Suppression Function of Porcine Reproductive and Respiratory Syndrome Virus

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    Citation: Li Y, Shyu D-L, Shang P, Bai J, Ouyang K, Dhakal S, Hiremath J, Binjawadagi B, Renukaradhya GJ, Fang Y. 2016. Mutations in a highly conserved motif of nsp1? protein attenuate the innate immune suppression function of porcine reproductive and respiratory syndrome virus. J Virol 90:3584–3599. doi:10.1128/JVI.03069-15.Porcine reproductive and respiratory syndrome virus (PRRSV) nonstructural protein 1? (nsp1?) is a multifunctional viral protein, which is involved in suppressing the host innate immune response and activating a unique ?2/?1 programmed ribosomal frameshifting (PRF) signal for the expression of frameshifting products. In this study, site-directed mutagenesis analysis showed that the R128A or R129A mutation introduced into a highly conserved motif (123GKYLQRRLQ131) reduced the ability of nsp1? to suppress interferon beta (IFN-?) activation and also impaired nsp1?'s function as a PRF transactivator. Three recombinant viruses, vR128A, vR129A, and vRR129AA, carrying single or double mutations in the GKYLQRRLQ motif were characterized. In comparison to the wild-type (WT) virus, vR128A and vR129A showed slightly reduced growth abilities, while the vRR129AA mutant had a significantly reduced growth ability in infected cells. Consistent with the attenuated growth phenotype in vitro, pigs infected with nsp1? mutants had lower levels of viremia than did WT virus-infected pigs. Compared to the WT virus in infected cells, all three mutated viruses stimulated high levels of IFN-? expression and exhibited a reduced ability to suppress the mRNA expression of selected interferon-stimulated genes (ISGs). In pigs infected with nsp1? mutants, IFN-? production was increased in the lungs at early time points postinfection, which was correlated with increased innate NK cell function. Furthermore, the augmented innate response was consistent with the increased production of IFN-? in pigs infected with mutated viruses. These data demonstrate that residues R128 and R129 are critical for nsp1? function and that modifying these key residues in the GKYLQRRLQ motif attenuates virus growth ability and improves the innate and adaptive immune responses in infected animals

    Evolutionary genomics of the pandemic 2009 H1N1 influenza viruses (pH1N 1v)

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    There are ongoing health risks posed by the pandemic 2009 H1N1 influenza viruses. This research provides a detailed phylogenetic analysis in 394 sequences of H1N1 viruses, taken from swine, human and avian sources from 1918 to 2009, to estimate a temporal reconstruction of reassortment history of 2009 H1N1 viruses. H1N1 influenza viruses were first isolated from swine in 1930; in Europe, avian H1N1 viruses were first detected in pigs in 1979. Pigs have been considered a possible “mixing vessel” in which genetic material can be exchanged. There is a potential for novel progeny viruses to arise, to which humans would be susceptible

    A multi-ancestry genome-wide study incorporating gene-smoking interactions identifies multiple new loci for pulse pressure and mean arterial pressure

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    Elevated blood pressure (BP), a leading cause of global morbidity and mortality, is influenced by both genetic and lifestyle factors. Cigarette smoking is one such lifestyle factor. Across five ancestries, we performed a genome-wide gene-smoking interaction study of mean arterial pressure (MAP) and pulse pressure (PP) in 129 913 individuals in stage 1 and follow-up analysis in 480 178 additional individuals in stage 2. We report here 136 loci significantly associated with MAP and/or PP. Of these, 61 were previously published through main-effect analysis of BP traits, 37 were recently reported by us for systolic BP and/or diastolic BP through gene-smoking interaction analysis and 38 were newly identified (P <5 x 10(-8), false discovery rate <0.05). We also identified nine new signals near known loci. Of the 136 loci, 8 showed significant interaction with smoking status. They include CSMD1 previously reported for insulin resistance and BP in the spontaneously hypertensive rats. Many of the 38 new loci show biologic plausibility for a role in BP regulation. SLC26A7 encodes a chloride/bicarbonate exchanger expressed in the renal outer medullary collecting duct. AVPR1A is widely expressed, including in vascular smooth muscle cells, kidney, myocardium and brain. FHAD1 is a long non-coding RNA overexpressed in heart failure. TMEM51 was associated with contractile function in cardiomyocytes. CASP9 plays a central role in cardiomyocyte apoptosis. Identified only in African ancestry were 30 novel loci. Our findings highlight the value of multi-ancestry investigations, particularly in studies of interaction with lifestyle factors, where genomic and lifestyle differences may contribute to novel findings.Peer reviewe

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

    A Novel Hybrid Approach to Selecting Marker Genes for Cancer Classification Using Gene Expression Data

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    Abstract—Selecting a subset of marker genes from thousands of genes is an important topic in microarray experiments for diseases classification and prediction. In this paper, we proposed a novel hybrid approach that combines gene ranking, heuristic clustering analysis and wrapper method to select marker genes for tumor classification. In our method, we firstly employed gene filtering to select the informative genes; secondly, we extracted a set of prototype genes as the representative of the informative genes by heuristic K-means clustering; finally, employed SVM-RFE to find marker genes from the representative genes based on recursive feature elimination. The performance of our method was evaluated by AML/ALL microarray dataset. The experimental results revealed that our method could find very small subset of marker genes with minimum redundancy but got better classification accuracy. Keywords-gene expression profiles, feature selection, heuristic clustering, prototype gene, SVM-RFE, cancer classification. I
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