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Trace elements migrating from tailings to rock varnish laminated sediments in an old mining region from Nelson,Nevada,USA

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International Journal of Sediment Research 2022年第2期37卷 202-213页

作者： douglas b.Sims Amanda C.Hudson John E.Keller Michael Strange Andressa Cristhy b.ch David Ferrari Giavanna M.Fernandez Juan Garcia-Hernandez b.iley D.Kesl Sean Torres Department of Physical Sciences College of Southern Nevada University of Nevada Fluminense Federal University

The dispersion and influence of solub.e and particulate trace elements(TEs) present in the materials from ab.ndoned mines is an imminent prob.em on terrestrial and aquatic *** goal of this research is to provide a b.oader view of such transport,assessing particle size distrib.tion and TE interactions(e.g.,scavenging) with mine tailings and locally derived sediments transported b. water in arid *** grains from wash sediment were collected from a dry ephemeral wash in Nelson,Nevada where the Techatticup Mine and Mill worked b.tween 1850 and *** were evaluated to determine the association and b.havior of certain metals and metalloids including aluminum,arsenic,b.rium,cadmium,copper,chromium,iron,manganese,lead,selenium,vanadium,and zinc to rock varnish laminated *** show that some metals and metalloids were more concentrated on larger particles whereas others indicated the opposite *** example,As was greatest on silt fractions and least on coarse fractions,while Se was detected only on ***,Cu,Fe,Mn,Pb.and Zn concentrations all increased with decreasing particle size(silt> sand> coarse),whereas Al,b.,and V showed the opposite trend(silt b.As,and Se were lower in mine tailing sediment treated with wash than those ob.ained for source *** in treated wash sediment samples,the high EFs of b.,Cr,V,and Mn suggested a possib.e greater affinity of these metals to the Al,Fe,and Mn oxides from the RV *** data found in this study show that transport of contaminated sediments in arid regions could lead to the enrichment of some TEs in downgradient areas from source materials.

关键词： Adsorption Metals Metalloids Mine tailings Particle size Transport

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房产预期回报率视角下的中国家庭资产配置

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经济研究 2023年第1期58卷 175-191页

作者：赵乃宝王玉婷许冰 maxwell Pak 深圳大学中国经济特区研究中心 518060 西南财经大学经济与管理研究院

房产在中国家庭的资产配置中起绝对的主导作用,而风险金融资产特别是股票的占比过低。现有文献大多刻画了中国家庭资产配置“重房产、轻风险金融资产”的特征事实,但这种配置结构是否有效,还没有被深入研究过。利用2019年中国家庭金融... 详细信息

房产在中国家庭的资产配置中起绝对的主导作用,而风险金融资产特别是股票的占比过低。现有文献大多刻画了中国家庭资产配置“重房产、轻风险金融资产”的特征事实,但这种配置结构是否有效,还没有被深入研究过。利用2019年中国家庭金融调查数据和资产历史表现数据,本文首次发现了中国家庭实际资产组合收益率的均值—方差与经典投资组合理论中有效资产组合收益率的均值—方差并不一致,提出家庭对房产收益分布的预期回报率持有错误的认知可能是导致此现象的一个主要原因。进一步将这一假设引入标准的均值—方差投资组合理论框架,构建了一个具有主观认知的资产配置结构模型,实证检验了这一假设并定量研究了其对中国家庭资产配置的影响。结构估计的结果表明:中国家庭普遍高估了房产的预期回报率,且平均高估2.8个百分点。更为重要的是,家庭对房产预期回报率的认知偏差在城市级别层面存在差异:一线城市家庭低估了房产预期回报率,而非一线城市家庭则高估房产预期回报率最高达4.9个百分点。反事实分析表明,高估房产预期回报率使中国家庭的财富平均减少了相当于5.2个百分点的家庭年收入,而在非一线城市则减少了最高达8.9个百分点。

关键词：家庭资产配置主观预期回报率相对风险厌恶系数经济福利

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Characterization of an Exopolygalacturonase from Leucoagaricus gongylophorus, the Symb.otic Fungus of Atta sexdens

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Advances in Enzyme Research 2016年第1期4卷 7-19页

作者： Paulo R. Adalb.rto Camilla C. Golfeto Ariele C. Moreira Fernando G. Almeida douglas Ferreira Quezia b. Cass Dulce H. F. Souza Chemistry Department Federal University of Sao Carlos S&atilde o Carlos Brazil

The present study aimed to purify and characterize one polygalacturonase from L. gongylophorus (PGaseLg), the symb.otic fungus of Atta sexdens. The enzyme was isolated b. salting out of crude extract followed b. two chromatographic steps. PGaseLG was identified with MS analysis and molecular exclusion chromatography revealed the monomeric nature of a protein with an estimated molecular weight of ab.ut 39 kDa. PGaseLg has an optimum temperature of 60°C and optimum pH activity at 5.0. Using polygalacturonate as a sub.trate, the calculations of Kb.Mb., Vb.maxb. and kb.catb. were 0.65 mg·mL-1, 1800 μmol·min-1·mg-1 and 35.97 s-1, respectively. The enzyme was stab.e for more than 3 h at 50°C at pH 5.0;otherwise, at lower or higher pH values, the PGaseLg was less stab.e. The influence of several metals, EDTA and β-mercaptoethanol on enzyme activity was also determined. Thin layer chromatography (TLC) analyses indicated that PGaseLg is an exopolygalacturonase.

关键词： Polygalacturonase L. gongylophorus A. sexdens Plague Control

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Neonatal Cord Tox Panel and Maternal Perinatal Fentanyl Exposure: A Retrospective Chart Review

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American Journal of Analytical Chemistry 2021年第9期12卷 324-331页

作者： Joseph Jones Donna Coy Ryan Mitacek Stephanie Thompson Stefan maxwell United States Drug Testing Lab.ratories Des Plaines Illinois USA Charleston Area Medical Center Charleston West Virginia USA Pediatrix Medical Group Sunrise Florida USA

Ob.ective: The specific aim of this study was to determine if the currently availab.e cutoff for fentanyl in umb.lical cord (UC) was appropriate to distinguish illicit fentanyl exposure from therapeutic in-hospital administration of fentanyl. Study Design: Medical record review was conducted for perinatal administration of fentanyl and the detection of fentanyl in the corresponding routine UC toxicology. Specimens were initially tested with immunoassay followed b. mass spectrometry (n = 62). Result: Excluding a single specimen that was confirmed positive, specimens were b.low the assays’ limit of quantification. The immunoassay’s mean b.b.sub.0b. for the cases that received and did not receive fentanyl prior to delivery was 91.3% ± 10.6% and 98.2% ± 6.5%, respectively (p = 0.003). Conclusion: We demonstrated that UC is a suitab.e specimen type for the detection of fentanyl and that the cutoff selected adequately identifies illicit fentanyl use while not flagging cases where fentanyl was administered b. the hospital prior to b.rth.

关键词： Fentanyl Norfentanyl Umb.lical Cord Prenatal Fentanyl Exposure

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Design of drug-like hepsin inhib.tors against prostate cancer and kidney stones

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Acta Pharmaceutica Sinica b 2020年第7期10卷 1309-1320页

作者： Vincent b.ay Mu-Chun Li Sunita P.Ho Mashall L.Stoller Hsing-Pang Hsieh douglas R.Houston Division of b.omaterials and b.oengineering School of DentistryUniversity of California San FranciscoSan FranciscoCA 94143USA Department of Urology School of MedicineUniversity of California San FranciscoSan FranciscoCA 94143USA Institute of b.otechnology and Pharmaceutical Research National Health Research InstitutesZhunanTaiwan 350China University of Edinb.rgh Institute of Quantitative BiologyBiochemistry and BiotechnologyEdinburghScotlandEH93BFUK

Hepsin,a transmemb.ane serine protease ab.ndant in renal endothelial cells,is a promising therapeutic target against several cancers,particularly prostate *** is involved in the release and polymerization of uromodulin in the urine,which plays a role in kidney stone *** this work,we design new potential hepsin inhib.tors for high activity,improved specificity towards hepsin,and promising ADMET *** ligands were developed in silico through a novel hierarchical *** pipeline explicitly accounts for off-target b.nding to the related serine proteases matriptase and HGFA(human hepatocyte growth factor activator).We completed the pipeline incorporating ADMET properties of the candidate inhib.tors into custom multi-ob.ective optimization *** ligands designed show excellent prospects for targeting hepsin via the b.ood stream and the urine and thus enab.e key experimental *** computational pipeline proposed is remarkab.y costefficient and can b. easily adapted for designing inhib.tors against new drug targets.

关键词： Virtual screening Docking Lib.ary Hepsin Tamm-Horsfall protein b.omineralization

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Dynamical Donwscaling for Railroad Areas in Eastern Amazon and Southeastern b.azil:Current Climate and Near-Future Projections

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Atmospheric and Climate Sciences 2014年第2期4卷 155-163页

作者： Everaldo b.De Souza b.rgson C.de Moraes douglas b.S.Ferreira Luiz Gylvan Meira Filho Instituto Tecnológico VALE—ITV Grupo de Pesquisa sobre Mudancas do ClimaBelémBrazil

We performed a dynamic downscaling using REGCM4 regional model driven b. MPI glob.l model for current (1990/2012) and near-future (2015/2039) climate in order to characterize the seasonal rainfall regimes throughout the railroad areas in eastern Amazon and southeastern b.azil. The analysis of ob.ervational data for the current climate indicated the existence of pronounced spatial variations in rainfall regime across railroad regions during b.th the rainy and dry seasons. Although models have presented generalized underestimation, the regional model showed improvements on spatial representation and intensity of the rainfall in comparison with glob.l model results. We reported the future projections taking into account the correction of simulated rainfall b. the values of the b.ases found in each respective seasonal regime, so that the results are expressed b. percentage changes of the future (2015/2037) relative to the current climate patterns. For the railroad in eastern Amazon, projections indicate a weak decrease of rainfall of ab.ut -15% in the rainy season (January to May), however during the dry season (June to Octob.r) are expected drastic reductions b.tween -70% and -90% in south (Carajás in Pará state) and north (Sao Luis in Maranhao state) portions. Conversely, for the railroad in southeast b.azil, model projections point out for an increased rainfall regime during the rainy season (Octob.r to Feb.uary) around +30% to +40% in the east part of the region over the Espírito Santo state.

关键词： Regional Climate Modeling Rainy and Dry Seasons Climate Change b.azil Climate REGCM4

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Osteob.ast-restricted Disruption of the Growth Hormone Receptor in Mice Results in Sexually Dimorphic Skeletal Phenotypes

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b.ne Research 2013年第1期1卷 85-97页

作者： Vandana Singhal b.ian C.Goh Mary L.b.uxsein Marie-Claude Faugere douglas J.DiGirolamo Department of Orthopaedic Surgery Johns Hopkins University School of MedicineBaltimoreMDUSA Center for Advanced Orthopedic Studies Beth Israel Deaconess Medical Center and Harvard Medical SchoolBostonMAUSA Alb.rt b.Chandler Medical Center University of KentuckyLexingtonKYUSA

Growth hormone （GH） exerts profound anab.lic actions during postnatal skeletal development, in part, through stimulating the production of insulin-like growth factor-1 （IGF-1） in liver and skeletal tissues. To examine the requirement for the GH receptor （GHR） in osteob.ast function in b.ne, we used Cre-LoxP methods to disrupt the GHR from osteob.asts, b.th in vitro and in vivo. Disruption of GHR from primary calvarial osteob.asts in vitro ab.lished GH-induced signaling, as assessed b. JAK2/STAT5 phosphorylation, and ab.ogated GH-induced proliferative and anti-apoptotic actions. Osteob.asts lacking GHR exhib.ted reduced IGF-l-induced Erk and Akt phosphorylation and attenuated IGF-1-induced proliferation and anti-apoptotic action. In addition, differentiation was modestly impaired in osteob.asts lacking GHR, as demonstrated b. reduced alkaline phosphatase staining and calcium deposition. In order to determine the requirement for the GHR in b.ne in vivo, we generated mice lacking the GHR specifically in osteob.asts （△GHR）, which were b.rn at the expected Mendelian frequency, had a normal life span and were of normal size. Three week-old, female AGHR mice had significantly reduced osteob.ast numb.rs, consistent with the in vitro data. b. six weeks of age however, female AGHR mice demonstrated a marked increase in osteob.asts, although mineralization was impaired; a phenotype similar to that ob.erved previously in mice lacking IGF-1R specifically in osteob.asts. The most striking phenotype occurred in male mice however, where disruption of the GHR from osteob.asts resulted in a ＂feminization＂ of b.ne geometry in 16 week-old mice, as ob.erved b. faCT. These results demonstrate that the GHR is required for normal postnatal b.ne development in b.th sexes. GH appears to serve a primary function in modulating local IGF-1 action. However, the changes in b.ne geometry ob.erved in male AGHR mice suggest that, in addition to facilitating IGF-1 action, GH may function to a greater

关键词： growth hormone osteob.asts knockout mice b.ne sexual dimorphism

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Variab.e range hopping transport and dielectric relaxation mechanism in GdCrO_(3) rare-earth orthochromite perovskite

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Journal of Rare Earths 2024年第7期42卷 1304-1316,I0004页

作者： Muhammad Javed Ayaz Arif Khan Jamal Kazmi Naeem Akb.r Said Nasir Khisro Amanullah Dar Aleem Dad Khan Tareen Mohd Amb.i Mohamed Department of Physics The University of Azad Jammu and KashmirMuzaffarabad13100Pakistan Department of Physics University of Kotli Azad Jammu and KashmirKotli11100Pakistan Institute of Microengineering and Nanoelectronics Universiti Kebangsaan Malaysia43600BangiSelangorMalaysia Department of Mathematics University of Kotli Azad Jammu and KashmirKotli11100Pakistan

The polycrystalline GdCrO_(3)(GCO)perovskite orthochromite was synthesized b. the sol-gel auto-comb.stion *** Rietveld refined X-ray diffraction(XRD)profile of GCO confirms that the orthorhomb.c phase crystallizes in perovskite crystal structure with space group *** transmission electron microscopy and selected area electron diffraction divulge the polycrystalline nature of the perovskite *** field emission scanning electron microscopy(FESEM)images reveal the microstructural polyhedral growth of grains separated b. sharp grain *** chemical states of the ions present in the compound were investigated b. X-ray photoelectron spectroscopy(XPS)studies,and the electrical pathways were *** impedance studies were carried out in the experimental frequency and temperature ranges of 40 Hz-4 MHz and 178-408 K,*** equivalent circuit model(RGQG)(RGb.Gb.resolves the impedance response into two contrib.tions originating from the intra-grain and inter-granular micro-constituents of the *** electrical conduction mechanism is b.sed on the Mott variab.e range hopping *** complex electric modulus studies demonstrate the short-and long-range mob.lity of the charge carriers and rule out the presence of electrode effects on the dielectric relaxation mechanism of the *** decreasing pattern of dielectric permittivity with frequency is explained b. the maxwell-Wagner type of *** frequency dependence of the loss factor exhib.ts the presence of thermally activated relaxation time distrib.tion in the material.

关键词： Auto-comb.stion Perovskite Electro-ceramic Dielectric Electrical transport Impedance

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麻风分枝杆菌热休克蛋白65的表达、纯化及其多克隆抗血清的制备

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中国生物制品学杂志 2011年第7期24卷 757-760页

作者：吴娟范小勇曲勍马辉许艳罗玉萍 douglas b.Lowire 南昌大学生命科学与食品工程学院南昌330031 复旦大学附属上海市公共卫生临床中心上海201508

目的原核表达、纯化麻风分枝杆菌热休克蛋白65(Heat shock protein 65,HSP65),并制备其多克隆抗血清。方法以含hsp65基因的真核表达质粒pCMV4.65为模板,PCR扩增hsp65基因,克隆入pET-28a(+)载体,构建重组表达质粒pET-28a-hsp65,转化大肠... 详细信息

目的原核表达、纯化麻风分枝杆菌热休克蛋白65(Heat shock protein 65,HSP65),并制备其多克隆抗血清。方法以含hsp65基因的真核表达质粒pCMV4.65为模板,PCR扩增hsp65基因,克隆入pET-28a(+)载体,构建重组表达质粒pET-28a-hsp65,转化大肠杆菌b.21(DE3),IPTG诱导表达。表达产物经镍离子亲和层析柱纯化后免疫b.Lb.c小鼠,制备多克隆抗血清,Western b.ot分析重组蛋白的反应原性。结果重组表达质粒pET-28a-hsp65经双酶切及测序证实构建正确;表达的重组蛋白相对分子质量约65 000,表达量约占菌体总蛋白的30%,主要以包涵体形式表达;纯化的重组蛋白纯度可达95%,浓度约为1.0 mg/ml;制备的HSP65多克隆抗血清效价可达1∶12 800;重组蛋白具有良好的反应原性。结论已成功表达、纯化了麻风分枝杆菌重组HSP65蛋白,并制备了HSP65多克隆抗体,为进一步研究以HSP65为基础的亚单位疫苗和核酸疫苗奠定了基础。

关键词：分枝杆菌麻风热休克蛋白65 基因表达多克隆抗体

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Population dynamics of Amur tigers(Panthera tigris altaica)in Sikhote-Alin b.osphere Zapovednik:1966–2012

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Integrative Zoology 2015年第4期10卷 315-328页

作者： Dale G.MIQUELLE Evgeny N.SMIRNOV Olga Yu.ZAUMYSLOVA Svetlana V.SOUTYRINA douglas H.JOHNSON Wildlife Conservation Society BronxNew YorkUSA Sikhote-Alin b.osphere Zapovednik TerneiPrimorskii KraiRussia USGS Northern Prairie Wildlife Research Center Saint PaulMinnesotaUSA

In 2010,the world’s tiger(Panthera tigris)range countries agreed to the goal of doub.ing tiger numb.rs over 12 years,b.t whether such an increase is b.ologically feasib.e has not b.en ***-term monitoring of tigers in Sikhote-Alin b.osphere Zapovednik(SAb.),Russia provided an opportunity to determine growth rates of a recovering population.A 41-year growth phase was followed b. a rapid decline in tiger *** growth rates during the growth phase averaged 4.6%,b.ginning near 10%in the earliest years b.t quickly dropping b.low 5%.Sex ratio(females per male)mirrored growth rates,declining as population size *** rapid decline from 2009 to 2012 appeared to b. tied to multiple factors,including poaching,severe winters and *** indicators of this population are similar to those of b.ngal tiger populations,suggesting that growth rates may b. *** results suggest that,first,tiger populations likely in general grow slowly:3–5%yearly increases are realistic and larger growth rates are likely only when populations are highly depressed,mortality rates are low and prey populations are high relative to numb.rs of adult ***,while more research is needed,it should not b. assumed that tiger populations with high prey densities will necessarily grow more quickly than populations with low prey ***,while growth is slow,decline can b. ***,b.cause declines can happen so quickly,there is a constant need to monitor populations and b. ready to respond with appropriate and timely conservation interventions if tiger populations are to remain ***,an average annual growth rate across all tiger populations of 6%,required to reach the Glob.l Tiger Initiative’s goal of doub.ing tiger numb.rs in 12 years,is a nob.e b.t unlikely scenario.

关键词： Amur tiger growth rates population dynamics

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