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A comparison of approaches in fitting continuum SEDs

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Research in Astronomy and Astrophysics 2013年第4期13卷 420-434页

作者： Yao Liu david Madlener Sebastian wolf Hong-chi Wang Purple Mountain Observatory and Key Laboratory for Radio Astronomy Chinese Academy of Sciences Graduate University of chinese Academy of Sciences Institut fr Theoretische Physik und Astrophysik Universitt zu Kiel

We present a detailed comparison of two approaches, the use of a precalculated database and simulated annealing （SA）, for fitting the continuum spectral energy distribution （SED） of astrophysical objects whose appearance is dominated by surrounding dust. While pre-calculated databases are commonly used to model SED data, only a few studies to date employed SA due to its unclear accuracy and convergence time for this specific problem. From a methodological point of view, different approaches lead to different fitting quality, demand on computational resources and calculation time. We compare the fitting quality and computational costs of these two approaches for the task of SED fitting to provide a guide to the practitioner to find a compromise between desired accuracy and available resources. To reduce uncertainties inherent to real datasets, we introduce a reference model resembling a typical circumstellar system with 10 free parameters. We derive the SED of the reference model with our code Mc3 D at 78 logarithmically distributed wavelengths in the range [0.3 μm, 1.3 mini and use this setup to simulate SEDs for the database and SA. Our result directly demonstrates the applicability of SA in the field of SED modeling, since the algorithm regularly finds better solutions to the optimization problem than a precalculated database. As both methods have advantages and shortcomings, a hybrid approach is preferable. While the database provides an approximate fit and overall probability distributions for all parameters deduced using Bayesian analysis, SA can be used to improve upon the results returned by the model grid.

关键词： methods numerical - radiative transfer - protoplanetary disks

Primary Non-HFE Hemochromatosis:A Review

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Journal of clinical and Translational Hepatology 2023年第4期11卷 925-931页

作者： Alla Turshudzhyan david c.Wu George Y.Wu Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterFarmingtonCTUSA

Iron homeostasis is a complex process in which iron uptake and use are tightly *** Type 1 or HFE hemochromatosis results from homozygous mutations in the gene that encodes human homeostatic iron regulator(known as human factors engineering,HFE)protein,a regulator of hepcidin,and makes up approximately 90%of all hemochromatosis ***,four types of hemochromatosis do not involve the HFE *** are non-HFE hemochromatosis type 2A(HFE2,encoding HJV),type 2B(HAMP,encoding hepcidin),type 3(TFR2,encoding transferring receptor-2),and types 4A and B(SLc40A1,encoding *** hemochromatosis is extremely *** allele frequencies have been estimated to be 74/100,000 for type 2A,20/100,000 for type 2B,30/100,000 for type 3,and 90/100,000 for type 4 *** guidelines recommend that the diagnosis be made by ruling out HFE mutations,history,physical examination,laboratory values(ferritin and transferrin saturation),magnetic resonance or other imaging,and liver biopsy if *** less common,non-HFE hemochromatosis can cause iron overload as severe as the HFE *** most cases,treatment involves phlebotomy and is successful if started before irreversible damage *** diagnosis and treatment are important because it prevents chronic liver *** review updates the mutations and their pathogenetic consequences,the clinical picture,diagnostic guidelines,and treatment of hemochromatosis.

关键词： Non-HFE Hemochromatosis cirrhosis Iron homeostasis

PcR-HRM for Genomic Surveillance of SARS-coV-2: A Variant Detection Tool in côte d’Ivoire, West Africa

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American Journal of Molecular Biology 2024年第3期14卷 166-185页

作者： Aboubacar Sylla Solange Kakou-Ngazoa Tata Gniré Safiatou coulibaly Yakoura Karidja Ouattara Mireille Sylvie Kouamé-Sina Zeinab Ouattara david Ngolo coulibaly Brice Kouakou Bla Mireille Dosso Molecular Biology Platform Pasteur Institute Cte dIvoire Abidjan Cte dIvoire Laboratory of Biology and Health UFR Biosciences University Flix Houphout Boigny Abidjan Cte dIvoire Genetic and cancer Laboratory Molecular Genetics Platform Pasteur Institute Cte dIvoire Abidjan Cte dIvoire Epidemic Virus Department Pasteur Institute Cte dIvoire Abidjan Cte dIvoire

The rise of new viruses, like SARS-coV-2 causing the cOVID-19 outbreak, along with the return of antibiotic resistance in harmful bacteria, demands a swift and efficient reaction to safeguard the health and welfare of the global population. It is crucial to have effective measures for prevention, intervention, and monitoring in place to address these evolving and recurring risks, ensuring public health and international security. In countries with limited resources, utilizing recombinant mutation plasmid technology in conjunction with PcR-HRM could help differentiate the existence of novel variants. cDNA synthesis was carried out on 8 nasopharyngeal samples following viral RNA extraction. The P1 segment of the SARS-coV-2 Spike S protein was amplified via conventional PcR. Subsequently, PcR products were ligated with the pGEM-T Easy vector to generate eight recombinant SARS-coV-2 plasmids. clones containing mutations were sequenced using Sanger sequencing and analyzed through PcR-HRM. The P1 segment of the S gene from SARS-coV-2 was successfully amplified, resulting in 8 recombinant plasmids generated from the 231 bp fragment. PcR-HRM analysis of these recombinant plasmids differentiated three variations within the SARS-coV-2 plasmid population, each displaying distinct melting temperatures. Sanger sequencing identified mutations A112c, G113T, A114G, G214T, and G216c on the P1 segment, validating the PcR-HRM findings of the variations. These mutations led to the detection of L452R or L452M and F486V protein mutations within the protein sequence of the Omicron variant of SARS-coV-2. In summary, PcR-HRM is a vital and affordable tool for distinguishing SARS-coV-2 variants utilizing recombinant plasmids as controls.

关键词： Genomic Surveillance SARS-coV-2 PcR-HRM Variants côte d’Ivoire

Suicide Mortality by Place,Gender,and Age Group-china,2010-2021

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china cDc weekly 2023年第25期5卷 559-564,I0003-I0005页

作者： Min Zhao Li Li Zhenzhen Rao david c.Schwebel Peishan Ning Guoqing Hu Department of Epidemiology and Health Statistics Hunan Provincial Key Laboratory of Clinical EpidemiologyXiangya School of Public HealthCentral South UniversityChangsha CityHunan ProvinceChina Department of Psychology University of Alabama at BirminghamBirminghamAlabamaUSA National clinical Research center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha CityHunan ProvinceChina

ABSTRAcT Introduction:Suicide is an important public health concern in *** examined suicide mortality by place,sex,and age group from 2010 to 2021 to identify and quantify significant suicide mortality changes in ***:We retrieved age-standardized and agespecific suicide mortality rates by place(urban ***)and sex from the chinese Health Statistical Yearbook and population data from the 2010 and 2020 chinese National Population census.

关键词： Place Population Suicide

Screening ionic liquids for efficiently extracting perfluoroalkyl chemicals (PFAcs) from wastewater

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Journal of Environmental Sciences 2023年第5期127卷 866-874页

作者： Kaihang Zhang david Kujawski chris Spurrell Bing Wang John ccrittenden Brook Byers Institute of Sustainable Systems and School of civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA 30332USA Refinery Water Engineering and Associates Hydrocarbon Processing Water and Waste TechnologyInc.HoustonTX 77042USA chevron USA VancouverWA 98664USA School of Municipal and Environmental Engineering Shenyang Jianzhu UniversityShenyang 110000China

Liquid-liquid extraction(LLE)using ionic liquids(ILs)-based methods to remove perfluoroalkyl chemicals(PFAcs),such as perfluorooctanoic acid(PFOA)and perfluorooctane sulfonic acid(PFOS),from wastewater,is an important ***,the lack of physicochemical and LLE data limits the selection of the most suitable ILs for the extraction of *** this work,1763 ILs for PFAcs extraction from water were systematically screened using cOSMOtherm to estimate the infinite dilution activity coefficient(lnγ^(∞))of PFOA and PFOS in water and *** evaluate the accuracy of cOSMOtherm,8 ILs with various lnγ^(∞)values were selected,and their extraction efficiency(E)and distribution coefficient(D_(exp))were measured *** results showed that the predicted lnγ^(∞)decreased as the increase of experimental extraction efficiency of PFOA or PFOS,while the tendency of predicted distribution coefficient(D_(pre))was consistent with the experimental(D_(exp))*** work provides an efficient basis for selecting ILs for the extraction of PFAcs from wastewater.

关键词： conductor-like screening model for real solvents(cOSMO-RS) Ionic liquids Perfluorooctanoic acid(PFOA) Perfluorooctane sulfonic acid(PFOS) Liquid-liquid extraction

Status of cry1Ac and cry2Ab2 resistance in field populations of Helicoverpa zea in Texas, USA

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Insect Science 2022年第2期29卷 487-495页

作者： Joséc.Santiago González david L.Kerns Graham P.Head Fei Yang Department of Entomology Texas A&M UniversityCollege StationTexasUSA Bayer crop Science St.LouisMissouriUSA

Helicoverpa zea is a major target pest of Bt corn and Bt ***-evolved resistance of *** to cry1 and cry2 proteins has been widely reported in the United *** the frequency of resistance alleles in a target insect is critical for Bt resistance *** multiple cases of practical resistance to cry proteins having been documented in ***,there are no data on the current status of alleles conferring resistance to cry1Ac and cry2Ab2 in field populations of this *** 2018‒2019,a total of 106 F2 families for cry1Ac and 120 F2 families for cry2Ab2 were established using mass mating and light trap *** screened 13,568 and 15,360 neonates using a discriminatory dose of cry1Ac and cry2Ab2,*** results showed that 93.4%and 35.0%of the F2 families could survive on the discriminatory dose of cry1Ac and cry2Ab2,*** estimated resistance allele frequency for cry1Ac in *** ranged from 0.4150 to 0.4975 and for cry2Ab2 ranged from 0.1097 and *** data indicate that the frequency of alleles conferring resistance to cry1 and cry2 proteins in *** in Texas are *** addition,our data suggest the resistance to cry1Ac and cry2Ab2 in the screened families of *** varies from recessive to *** information in this study provides precise estimates of cry resistance allele frequencies in *** and increases our understanding of the risks to the sustainability of Bt crops.

关键词： allele frequency Bacillus thuringiensis crylAc cry2Ab2 Helicoverpa zea resistance

Nanoscale chemical segregation to twin interfaces in τ-MnAl-c and resulting effects on the magnetic properties

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Journal of Materials Science & Technology 2023年第3期134卷 22-32页

作者： Panpan Zhao Markus Gusenbauer Harald Oezelt Daniel wolf Thomas Gemming Thomas Schrefl Kornelius Nielsch Thomas George Woodcock Leibniz IFW Dresden Helmholtzstr.20Dresden 01069Germany TU Dresden Institute of Materials ScienceDresden 01062Germany Department for Integrated Sensor Systems Danube University KremsKrems an der Donau 3500Austria

In this study,aberration-corrected scanning transmission electron microscopy coupled with electron energy-loss spectroscopy(STEM-EELS)was used to investigate the atomistic structure and chemical com-position of true twin and order twin boundaries in ferromagneticτ-*** twins and order twins were distinguished based on the diffraction patterns using *** elemental segregation was observed at the coherent true twin boundary but some Mn enrichment within a region of about 1.5-2 nm was found at the incoherent true twin boundary.A transition region with Mn enrichment about 4-6 nm wide was found at the order twin boundary.A carbon cluster with a size of around 5 nm was also found at the twin *** simulations were conducted to study the effect of this chemical seg-regation at twin interfaces on the magnetic *** results showed that the coercivity tends to increase with increasing structural and chemical disorder at the interface.

关键词： τ-MnAl-c Twin boundaries Elemental segregation STEM-EELS Micromagnetic simulations

Nb含量对X70钢级直缝埋弧焊管组织及强韧性的影响

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钢管 2024年第1期53卷 29-34页

作者：何小东张永青 HAN david 陈越峰杨耀彬中国石油集团工程材料研究院有限公司·石油管材及装备材料服役行为与结构安全国家重点实验室陕西西安710077 国际焊接研究中心陕西西安710077 中信金属股份有限公司北京100004

检测了Nb含量为0.046%和0.075%的X70直缝埋弧焊管的强韧性,分析了管体的微观组织。结果表明:随着Nb含量升高,管体的平均晶粒尺寸减小,组织由PF+B_(粒)转变为以B_(粒)为主;管体横向拉伸应力-应变曲线均为典型的“拱顶”型,拉伸性能均满... 详细信息

检测了Nb含量为0.046%和0.075%的X70直缝埋弧焊管的强韧性,分析了管体的微观组织。结果表明:随着Nb含量升高,管体的平均晶粒尺寸减小,组织由PF+B_(粒)转变为以B_(粒)为主;管体横向拉伸应力-应变曲线均为典型的“拱顶”型,拉伸性能均满足要求,但含量为0.075%Nb的管体的横向屈服强度和抗拉强度较高;Nb含量相同时,c含量越高,其屈服强度和抗拉强度越高;含量为0.075%Nb的钢管具有更好的低温冲击韧性,但含量为0.046%Nb的钢管的韧-脆转变曲线具有更高的上平台能。Nb含量较高、c含量较低的钢管的热影响区也具有更好的低温韧性。探讨了c、Nb元素的含量及组织类型、析出相和位错密度对X70管线钢强韧性的影响。

关键词：直缝埋弧焊管管线钢 X70 铌含量微观组织强韧性

补体相关蛋白在HIV/AIDS湿热内蕴证患者中的差异性表达

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中国艾滋病性病 2024年第6期30卷 579-583页

作者：孙雪晴王亚楠张海燕冯龙 david Y.W.Lee 苏铄涵徐立然 Alan Wang 李青雅河南中医药大学中医学院郑州450000 河南中医药大学第一附属医院郑州450000 河南中医药大学医学院郑州450000 Harvard Medical School MA Boston 02115 Faculty of Medicine and Health Sciences of Auckland University New Zealand 6000

目的探讨补体系统相关因子在HIV/AIDS患者中及其与HIV/AIDS湿热内蕴证侯的表达特征。方法共纳入2023年3-5月于广西壮族自治区某地区就诊的HIV/AIDS患者(简称HIV组),其中包括HIV/AIDS湿热内蕴证患者组(简称HIVsr组)与HIV/AIDS无证可辨... 详细信息

目的探讨补体系统相关因子在HIV/AIDS患者中及其与HIV/AIDS湿热内蕴证侯的表达特征。方法共纳入2023年3-5月于广西壮族自治区某地区就诊的HIV/AIDS患者(简称HIV组),其中包括HIV/AIDS湿热内蕴证患者组(简称HIVsr组)与HIV/AIDS无证可辨患者组(简称HIVwz组)及同期在门诊进行体检的健康对照组。收集其基本信息并采集抗凝血液,应用流式细胞术检测T细胞亚群数量,酶联免疫吸附试验检测补体相关因子血浆表达水平,对数据进行统计分析。结果共纳入HIV组45例,其中包括HIVsr组30例与HIVwz组15例,与健康对照组15例。免疫指标对比中,HIVsr组与健康对照组相比TH/TS表达下降(Pc3、c5aR、c5b因子外,c1q、MASP2、MBL等12个因子表达均下降(Pc1q、c5aR、IL-6、TNF-α表达显著降低(Pc3aR与湿热内蕴证证候学量表积分呈负相关(r=-0.613,Pc3aR是量表积分的影响因素。结论补体系统中经典及凝集素通路参与HIV/AIDS患者病理过程,且HIV/AIDS湿热内蕴证患者的证候生物学基础与经典通路相关。c3aR对临床诊断HIV/AIDS湿热内蕴证患者有一定鉴别价值。

关键词：艾滋病湿热内蕴证补体证候诊断