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Effect of Elevated cO_2 and Drought on Soil Microbial communities Associated with Andropogon gerardii

Journal of Integrative Plant Biology 2008年第11期50卷 1406-1415页

作者： Issmat I. Kassem Puneet Joshi Yon Sigler scott Heckathorn Qi Wang Department of Environmental Sciences University of Toledo Ohio 43606 USA Department of civil Engineering University of Toledo Ohio 43606 USA

Our understanding of the effects of elevated atmospheric cO2, singly and in combination with other environmental changes, on plant-soil interactions is incomplete. Elevated cO2 effects on c4 plants, though smaller than on c3 species, are mediated mostly via decreased stomatal conductance and thus water loss. Therefore, we characterized the interactive effect of elevated cO2 and drought on soil microbial communities associated with a dominant c4 prairie grass, Andropogon gerardii Vitman. Elevated cO2 and drought both affected resources available to the soil microbial community. For example, elevated cO2 increased the soil c：N ratio and water content during drought, whereas drought alone decreased both. Drought significantly decreased soil microbial biomass. In contrast, elevated cO2 increased biomass while ameliorating biomass decreases that were induced under drought. Total and active direct bacterial counts and carbon substrate use （overall use and number of used sources） increased significantly under elevated cO2. Denaturing gradient gel electrophoresis analysis revealed that drought and elevated cO2, singly and combined, did not affect the soil bacteria community structure. We conclude that elevated cO2 alone increased bacterial abundance and microbial activity and carbon use, probably in response to increased root exudation. Elevated cO2 also limited drought-related impacts on microbial activity and biomass, which likely resulted from decreased plant water use under elevated cO2. These are among the first results showing that elevated cO2 and drought work in opposition to modulate plant-associated soil-bacteria responses, which should then influence soil resources and plant and ecosystem function.

关键词： denaturing gradient gel electrophoresis drought elevated cO2 soil microbial communities.

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跨音速转子叶顶泄漏流/主流交界面的前移机制

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工程热物理学报 2011年第6期32卷 929-932页

作者：杜娟林峰陈静宜 Mark H Ross Joshua D cameron scott c Morris 中国科学院工程热物理研究所北京100190 中国科学院先进能源与动力重点实验室北京100190 Hessert Laboratory Department of Mechanical and Aerospace EngineeringUniversity of Notre Dame

采用数值计算和实验研究相结合的方法,研究了跨音速转子叶顶泄漏流与主流交界面轴向位置随流量的变化规律和机制。该跨音转子是美国圣母大学一级半跨音速压气机转子。研究发现机匣壁面脉线分布能够定性反映壁面轴向剪切应力分布,可用来... 详细信息

采用数值计算和实验研究相结合的方法,研究了跨音速转子叶顶泄漏流与主流交界面轴向位置随流量的变化规律和机制。该跨音转子是美国圣母大学一级半跨音速压气机转子。研究发现机匣壁面脉线分布能够定性反映壁面轴向剪切应力分布,可用来识别叶顶泄漏流与主流的交界面位置。通过机匣壁面的脉线分布,可以看出机匣壁面存在两条零剪切应力线。第一条零剪切应力线表示来流与叶顶泄漏流之间交界面的时间和周向平均轴向位置,在小流量工况下交界面靠近顶部叶片的前缘。计算和实验结果都表明,随着质量流量的减小,叶顶泄漏流与主流交界面的轴向位置不断向叶片前缘移动。在近失速点,交界面到达叶片前缘,泄漏流即将溢出。泄漏流与主流的轴向动量比随流量减小不断增大的变化规律进一步说明,间隙区域泄漏流与主流的轴向动量平衡是导致交界面不断前移直至溢出的内在机制。

关键词：叶顶泄漏流/主流交界面轴向剪切应力跨音速压气机转子

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Passive expansion of sub-maximally dilated transjugular intrahepatic portosystemic shunts and assessment of clinical outcomes

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World Journal of Hepatology 2017年第12期9卷 603-612页

作者： Michael c Hsu charles N Weber S William Stavropoulos Timothy W clark scott O Trerotola Richard D Shlansky Goldberg Michael c Soulen Gregory J Nadolski Department of Radiology Division of Interventional RadiologyMount Sinai Hospital Department of Radiology Division of Interventional RadiologyHospital of the University of Pennsylvania

AIM To assess for passive expansion of sub-maximally dilated transjugular intrahepatic portosystemic shunts(TIPS) and compare outcomes with maximally dilated *** Polytetrafluoroethylene covered TIPS(Viatorr) from July 2002 to December 2013 were retrospectively reviewed at two hospitals in a single institution. Two hundred and thirty patients had TIPS maximally dilated to 10 mm(m TIPS), while 43 patients who were at increased risk for hepatic encephalopathy(HE), based on clinical evaluation or low pre-TIPS portosystemic gradient(PSG), had 10 mm TIPS sub-maximally dilated to 8 mm(sm TIPS). Group characteristics(age, gender, Model for End-Stage Liver Disease score, post-TIPS PSG and clinical outcomes were compared between groups, including clinical success(ascites or varices), primary patency,primary assisted patency, and severe post-TIPS HE. A subset of fourteen patients with sm TIPS underwent follow-up computed tomography imaging after TIPS creation, and were grouped based on time of imaging( 6 mo). change in diameter and crosssectional area were measured with 3D imaging software to evaluate for passive *** Patient characteristics were similar between the sm TIPS and m TIPS groups, except for pre-TIPS portosystemic gradient, which was lower in the sm TIPS group(19.4 mm Hg ± 6.8 vs 22.4 mm Hg ± 7.1, P = 0.01). Primary patency and primary assisted patency between sm TIPS and m TIPS was not significantly different(P = 0.64 and 0.55, respectively). Four of the 55 patients(7%) with sm TIPS required TIPS reduction for severe refractory HE, while this occurred in 6 of the 218 patients(3%) with m TIPS(P = 0.12). For the 14 patients with follow-up computed tomography(cT) imaging, the median imaging follow-up was 373 d. There was an increase in median TIPS diameter, median percent diameter change, median area, and median percent area change in patients with cT follow-up greater than 6 mo after TIPS placement compared to follow-up within 6 mo(

关键词： Variceal hemorrhage Portal hypertension Transjugular intrahepatic portosystemic shunts Ascites Sub-maximal dilation Underdilated Passive expansion Hepatic encephalopathy

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Detection,management,and prevention of diabetes-related foot disease in the Australian context

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World Journal of Diabetes 2023年第7期14卷 942-957页

作者： scott McNeil Kate Waller Yves S Poy Lorenzo Olimpia c Mateevici Stacey Telianidis Sara Qi Irina churilov Richard J MacIsaac Anna Galligan High Risk Foot Service St Vincent’s Hospital MelbourneFitzroy 3065VictoriaAustralia Department of Endocrinology and Diabetes St Vincent’s Hospital MelbourneFitzroy 3065VictoriaAustralia Department of Podiatry St Vincent’s Hospital MelbourneFitzroy 3065VictoriaAustralia Infectious Diseases Unit Department of MedicineSt Vincent’s Hospital MelbourneFitzroy 3065VictoriaAustralia Department of Pharmacy St Vincent’s Hospital MelbourneFitzroy 3065Australia Department of Medicine St Vincent’s Hospital MelbourneUniversity of MelbourneFitzroy 3065VictoriaAustralia Department of Vascular Surgery St Vincent’s Hospital MelbourneFitzroy 3065VictoriaAustralia Department of Rehabilitation Medicine St Vincent’s Hospital MelbourneFitzroy 3065VictoriaAustralia the Australian centre for Accelerating Diabetes Innovations School of MedicineUniversity of MelbourneParkville 3010VictoriaAustralia

Diabetes-related foot disease(DFD)is a widely feared complication among people who live with *** Australia and globally,rates of disability,cardiovascular disease,lower extremity amputation,and mortality are significantly increased in patients with *** order to understand and prevent these outcomes,we analyse the common pathogenetic processes of neuropathy,arterial disease,and *** review then summarises important management considerations through the interdisciplinary *** Australian and international guidelines,we offer a stepwise,evidence-based practical approach to the care of patients with DFD.

关键词： Diabetes-related foot disease Foot ulceration Lower extremity amputation Neuropathy Peripheral arterial disease Infection

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Hepatocellular carcinoma incidence post direct-acting antivirals in hepatitis c-related advanced fibrosis/cirrhosis patients in Australia

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Hepatobiliary & Pancreatic Diseases International 2020年第6期19卷 541-546页

作者： Patrick P Y chan Miriam T Levy Nicholas Shackel scott A Davison Emilia Prakoso Department of Gastroenterology and Hepatology Liverpool HospitalElizabeth StreetLiverpoolNSW 2170Australia South Western clinical School University of New South WalesLiverpoolNSW 2170Australia central clinical School-The Faculty of Medicine and Health University of SydneyNSW 2050Australia

Background:Despite efficacy in HcV eradication,direct-acting antiviral(DAA)therapy has raised controversies around their impact on hepatocellular carcinoma(Hcc)*** we reported the first Australian data on Hcc incidence in DAA-treated HcV patients with advanced fibrosis/***:We conducted a retrospective single center study of DAA-treated HcV patients with advanced fibrosis/cirrhosis from April 2015 to December *** with prior Hcc were included if they had complete response to Hcc ***:Among 138 patients who completed DAA therapy,133(96.4%)achieved sustained virologic response(median follow-up 23.8 months).Ten had prior Hcc and 5/10(50.0%)developed recurrence,while de novo Hcc developed in 7/128(5.5%).Median time from DAA to Hcc diagnosis was 34 weeks in recurrent Hcc *** novo 52 weeks(P=0.159).In patients with prior Hcc,those with recurrence(***)had shorter median time between last Hcc treatment and DAA(12 vs.164 weeks,Pc response at 12 weeks(SVR12)(P=0.011),platelets(P=0.005),model for end-stage liver disease(MELD)score(P=0.029),alpha fetoprotein(AFP)(P=0.013),and prior Hcc(Pciated with Hcc *** multivariate analysis,significant factors were prior Hcc(OR=4.80;95%cI:1.47–48.50;P=0.010),failed SVR12(OR=2.83;95%cI:1.71–16.30;P=0.016)and platelets(OR=0.97;95%cI:0.95–0.99;P=0.009).conclusions:Our study demonstrates a high incidence of recurrent Hcc in HcV patients with advanced fibrosis/cirrhosis treated with *** associated with Hcc development post-DAA were more advanced liver disease,failed SVR12 and prior Hcc,with higher rates of recurrence in those who started DAA earlier.

关键词： Direct-acting antiviral cirrhosis Hepatitis-c virus Hepatocellular carcinoma Recurrence

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Elucidating the impact of the ionomer equivalent weight on a platinum group metal-free PEMFc cathode via oxygen limiting current

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SusMat 2023年第1期3卷 72-90页

作者： HaoWang Luigi Osmieri Haoran Yu Michael J.Zachman Jae Hyung Park Nancy N.Kariuki Firat c.cetinbas Sunilkumar Khandavalli scott Mauger Deborah J.Myers David A.cullen Kenneth c.Neyerlin chemistry and Nanoscience center National Renewable Energy LaboratoryGoldenColoradoUSA center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTennesseeUSA chemical Sciences and Engineering Division Argonne National LaboratoryLemontIllinoisUSA Nuclear Science and Engineering Division Argonne National LaboratoryLemontIllinoisUSA

Leveraging the interactions between ionomer and catalyst can increase the performance of proton exchangemembrane fuel *** impacts of the equivalent weight(EW)of perfluorosulfonic acid-based ionomers on the platinum group metal-free electrode structure and fuel cell performance have not been fully *** membrane electrode assemblies(MEAs)were prepared by using a commercial Fe-N-c catalyst,two perfluorosulfonic acid ionomers with different EWs,that is,Aquivion 720(A720)and Nafion 1100(N1100),and two ionomer-tocatalyst(I/c)*** four MEAswere characterized to understand the impact of the ionomer EW and content on the capacitance,proton conductivity,and mass transport on the *** mass transport resistance was measured for the first time using a new oxygen reduction reaction limiting current method enabling to couple the effects of oxygen diffusion with liquid water *** EW ionomer combined with a moderate I/c results in improved performance due to its enhanced proton ***,when used at high I/c,it can cause severewater flooding at high current density due to the enhanced liquid water uptake,especially at high relative humidity,resulting in lower catalyst utilization and higher mass transport resistance.

关键词： ionomer equivalent weight limiting current mass transport oxygen reduction reaction PGMfree catalyst proton exchange membrane fuel cell

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Heterozygous carriers of galactocerebrosidase mutations that cause Krabbe disease have impaired microglial function and defective repair of myelin damage

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Neural Regeneration Research 2018年第3期13卷 393-401页

作者： Nicole J.scott-Hewitt christopher J.Folts Mark D.Noble Department of Biomedical Genetics University of Rochester School of Medicine and Dentistry

This review addresses two puzzling findings related to mutations in galactocerebrosidase （GALc） that cause Krabbe disease （KD）, a severe lysosomal storage disorder characterized by extensive myelin damage in children with mutations in both GALc alleles. First, heterozygous carriers of KD-causing mutations, which include the biological parents of children with KD, exhibit increased risk for developing other diseases. Second, variants in the GALc locus increase the risk of developing multiple sclerosis （MS）, another disease characterized by extensive myelin damage. What explains these correlations？ In studies on cuprizone-induced myelin damage in heterozygous （GALc＋/–） mice carrying one copy of a mutation that causes KD-like disease, the extent of damage was similar in GALc＋/– and wild-type （WT） mice. In contrast, GALc＋/- mice had striking defects in repair of cuprizone-induced damage. We further found unexpected microglial defects in myelin debris clearance and in the ability to up-regulate the Trem2 microglial protein critical for debris uptake. These defects were rescued by exposure to a lysosomal re-acidifying drug discovered in our studies on KD, and which provides multiple clinically relevant benefits in the twitcher （GALc＋/–） mouse model of KD. Thus, heterozygous GALc mutations cause effects on biological function that may help to understand the increased disease risk in heterozygous carriers of such mutations and to understand why GALc variations increase the risk of MS. Our findings indicate that while some genetic risk factors may contribute to complex diseases by increasing the risk of tissue damage, others may do so by compromising tissue repair.

关键词： vulnerability locus multiple sclerosis Krabbe disease galactocerebrosidase microglia myelin repair lysosomal storage disorders heterozygous carriers Trem2 demyelination

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Single Nucleotide Polymorphism Identification in Polyploids： A Review, Example, and Recommendations

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Molecular Plant 2015年第6期8卷 831-846页

作者： Josh clevenger carolina chavarro Stephanie A. Pearl Peggy Ozias-Akins scott A. Jackson center for AppLied Genetic Technologies University of Georgia Athens GA 30602 USA Institute of Plant Breeding Genetics & Genomics University of Georgia Tifton GA 31793 USA These authors contributed equally to this article.

Understanding the relationship between genotype and phenotype is a major biological question and being able to predict phenotypes based on molecular genotypes is integral to molecular breeding. Whole- genome duplications have shaped the history of all flowering plants and present challenges to elucidating the relationship between genotype and phenotype, especially in neopolyploid species. Although single nucleotide polymorphisms （SNPs） have become popular tools for genetic mapping, discovery and appli- cation of SNPs in polyploids has been difficult. Here, we summarize common experimental approaches to SNP calling, highlighting recent polyploid successes. To examine the impact of software choice on these analyses, we called SNPs among five peanut genotypes using different alignment programs （BWA-mem and Bowtie 2） and variant callers （SAMtools, GATK, and Freebayes）. Alignments produced by Bowtie 2 and BWA-mem and analyzed in SAMtools shared 24.5% concordant SNPs, and SAMtools, GATK, and Freebayes shared 1.4% concordant SNPs. A subsequent analysis of simulated Brassica napus chromosome 1A and 1c genotypes demonstrated that, of the three software programs, SAMtools performed with the highest sensitivity and specificity on Bowtie 2 alignments. These results, however, are likely to vary among species, and we therefore propose a series of best practices for SNP calling in polyploids.

关键词： genomics homeolog next-generation sequencing (NGS) peanut polyptoid single nucleotide poly-morphism (SNP)

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Experimental and Modeling Study of Forest Fire Effect on Soil Thermal conductivity

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Pedosphere 2016年第4期26卷 462-473页

作者： Kathleen M.SMITS Elizabeth KIRBY William J.MASSMAN Larry scott BAGGETT center for the Experimental Study of Subsurface Environmental Processes Department of Civil and Environmental EngineeringColorado School of Mines USDA Forest Service Rocky Mountain Research Station

An understanding of soil thermal conductivity after a wildfire or controlled burn is important to land management and post-fire recovery efforts. Although soil thermal conductivity has been well studied for non-fire heated soils, comprehensive data that evaluate the long-term effect of extreme heating from a fire on the soil thermal conductivity are limited. The purpose of this study was to evaluate the long-term impact of fire on the effective thermal conductivity of soils by directly comparing fire-heated and no-fire control soils through a series of laboratory studies. The thermal conductivity was measured for ten soil samples from two sites within the Manitou Experimental Forest, colorado, USA, for a range of water contents from saturation to the residual degree of saturation. The thermal conductivity measured was compared with independent estimates made using three empirical models from literature, including the campbell et al. （1994）, cSt~ and Konrad （2005）, and Massman et al. （2008） models. Results demonstrate that for the test soils studied, the thermal conductivity of the fire-heated soils was slightly lower than that of the control soils for all observed water contents. Modeling results show that the campbell et al. （1994） model gave the best agreement over the full range of water contents when proper fitting parameters were employed. Further studies are needed to evaluate the significance of including the influence of fire burn on the thermal properties of soils in modeling studies.

关键词： controlled burn degree of saturation empirical model water content wildfire

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Machine-learning-based intelligent framework for discovering refractory high-entropy alloys with improved high-temperature yield strength

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npj computational Materials 2022年第1期8卷 2247-2257页

作者： Stephen A.Giles Debasis Sengupta scott R.Broderick Krishna Rajan cFD Research corporation 6820 Moquin Dr.NWHuntsvilleAL35806US Department of Material Design and Innovation University at Buffalo120 Bonner HallBuffaloNY14260USA

Refractory high-entropy alloys(RHEAs)show significant elevated-temperature yield strengths and have potential to use as high-performance materials in gas turbine *** the vast RHEA compositional space experimentally is challenging,and a small fraction of this space has been explored to *** work demonstrates the development of a state-of-the-art machine learning framework coupled with optimization methods to intelligently explore the vast compositional space and drive the search in a direction that improves high-temperature yield *** yield strength model is shown to have a significantly improved predictive accuracy relative to the state-of-the-art approach,and also provides inherent uncertainty quantification through the use of repeated k-fold *** developing and validating a robust yield strength prediction model,the coupled framework is used to discover RHEAs with superior high temperature yield *** have shown that RHEA compositions can be customized to have maximum yield strength at a specific temperature.

关键词： strength alloys entropy

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