279 research outputs found

    ORIGIN AND QUANTIFICATION OF DIFFUSE CO2 AND H2S EMISSION AT CRATER HILLS, YELLOWSTONE NATIONAL PARK

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    At Crater Hills, a thermally-altered area adjoining the Sour Creek resurgent dome that is located within the Yellowstone Caldera, we characterized volatile emissions based upon our soil degassing measurements and soil gas chemistry in 2014 and fumarole gas chemistry in 2007 (Bergfeld et al., 2011). The investigation at Crater Hills on its diffuse gases isotopes and CO2, H2S emission improve our understanding on its gas emission mode – including total emission and spatial distribution, and contribute to a more accurate estimation of total CO2 emission at Yellowstone volcanic system. The total emission of CO2 interpolated by sequential Gaussian simulation method (sGs) was 66 to 109 t d-1 with 95% confidence, which is an underestimation due to the inability to measure a high flux area on a slope as well as the absence of fumarole and pool emissions. Indicated by gas chemistry data of the fumarole at Crater Hills in 2007, the proportion of CO2 derived from magma would be at least 38% if considering the worst and unreasonable scenario; other scenarios give a much higher proportion of magma component, which would be over 50%. Faults or fractures covered by overlying alluvium are very likely to exist at Crater Hills, based on the similarity between the connection of high flux areas and the trend of the regional faults. The estimated emission of H2S was 0.39 t d-1, based on the linear correlation between H2S and CO2. The heat output was also estimated to be ~35MW with average heat flux of ~100 W m-2 based upon CO2-H2O-heat relations. The temperature of liquid-dominated reservoir was estimated to be 270-300 ⁰C estimated by Fournier (1989), and was 213 ⁰C to 217 ⁰C for the vapor-dominated reservoir which is the source for the sampled fumarole gas in 2007

    Learning the hub graphical Lasso model with the structured sparsity via an efficient algorithm

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    Graphical models have exhibited their performance in numerous tasks ranging from biological analysis to recommender systems. However, graphical models with hub nodes are computationally difficult to fit, particularly when the dimension of the data is large. To efficiently estimate the hub graphical models, we introduce a two-phase algorithm. The proposed algorithm first generates a good initial point via a dual alternating direction method of multipliers (ADMM), and then warm starts a semismooth Newton (SSN) based augmented Lagrangian method (ALM) to compute a solution that is accurate enough for practical tasks. The sparsity structure of the generalized Jacobian ensures that the algorithm can obtain a nice solution very efficiently. Comprehensive experiments on both synthetic data and real data show that it obviously outperforms the existing state-of-the-art algorithms. In particular, in some high dimensional tasks, it can save more than 70\% of the execution time, meanwhile still achieves a high-quality estimation.Comment: 28 pages,3 figure

    The contribution of Alu exons to the human proteome.

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    BackgroundAlu elements are major contributors to lineage-specific new exons in primate and human genomes. Recent studies indicate that some Alu exons have high transcript inclusion levels or tissue-specific splicing profiles, and may play important regulatory roles in modulating mRNA degradation or translational efficiency. However, the contribution of Alu exons to the human proteome remains unclear and controversial. The prevailing view is that exons derived from young repetitive elements, such as Alu elements, are restricted to regulatory functions and have not had adequate evolutionary time to be incorporated into stable, functional proteins.ResultsWe adopt a proteotranscriptomics approach to systematically assess the contribution of Alu exons to the human proteome. Using RNA sequencing, ribosome profiling, and proteomics data from human tissues and cell lines, we provide evidence for the translational activities of Alu exons and the presence of Alu exon derived peptides in human proteins. These Alu exon peptides represent species-specific protein differences between primates and other mammals, and in certain instances between humans and closely related primates. In the case of the RNA editing enzyme ADARB1, which contains an Alu exon peptide in its catalytic domain, RNA sequencing analyses of A-to-I editing demonstrate that both the Alu exon skipping and inclusion isoforms encode active enzymes. The Alu exon derived peptide may fine tune the overall editing activity and, in limited cases, the site selectivity of ADARB1 protein products.ConclusionsOur data indicate that Alu elements have contributed to the acquisition of novel protein sequences during primate and human evolution

    Pin on Disc Wear volume Prediction Based on Grey System Theory

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    This paper is a study of pin on disc wear volume, with the MMW-1A vertical friction and wear testing machine as the testing equipment, under different lubrication conditions. In this paper, the pin wear volume GM(1,1) prediction model is built based on the grey system theory, GM(1,1) the model consists of a single variable in the first-order differential equation. The pin wear volume measured compare with GM(1,1) predicted wear volume, The comparison results showed that, the predicted values by the GM(1,1) are very close to the experiment measured values, and the precision of predicted results is quite high

    Continuous Femoral Nerve Block versus Intravenous Patient Controlled Analgesia for Knee Mobility and Long-Term Pain in Patients Receiving Total Knee Replacement: A Randomized Controlled Trial

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    Objectives. To evaluate the comparative analgesia effectiveness and safety of postoperative continuous femoral nerve block (CFNB) with patient controlled intravenous analgesia (PCIA) and their impact on knee function and chronic postoperative pain. Methods. Participants were randomly allocated to receive postoperative continuous femoral nerve block (group CFNB) or intravenous patient controlled analgesia (group PCIA). Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores for knee and incidence of chronic postoperative pain at 3, 6, and 12 months postoperatively were compared. postoperative pain and salvage medication at rest or during mobilization 24 hours, 48 hours, and 7 days postoperatively were also recorded. Results. After discharge from the hospital and rehabilitation of joint function, patients in group CFNB reported significantly improved knee flexion and less incidence of chronic postoperative pain at 3 months and 6 months postoperatively (P<0.05). Analgesic rescue medications were significantly reduced in patients receiving CFNB (P<0.001 and P=0.031, resp.). Conclusion. With standardized rehabilitation therapy, continuous femoral nerve block analgesia reduced the incidence of chronic postoperative pain, improved motility of replaced joints, and reduced the dosages of rescue analgesic medications, suggesting a recovery-enhancing effect of peripheral nerve block analgesia

    Feasibility of peaking carbon emissions of the power sector in China’s eight regions: decomposition, decoupling, and prediction analysis

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    Abstract(#br)Carbon emissions in the power sector are an important part of China’s total carbon emissions and have a significant impact on whether China can achieve the 2030 carbon peak target. Based on the three perspectives of decomposition, decoupling, and prediction, this paper studies the feasibility of carbon emission peaks in eight major regional power sectors in China. First, the generalized Divisia index model (GDIM) is used to decompose the carbon emissions of the eight regional power sectors, and the driving factors and their effects on carbon emissions in the power sector of each region are compared. Then, the decoupling index based on the generalized Divisia index model (GDIM-D) is used to study the decoupling relationship between the carbon emissions of the eight regional..
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