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Seism.c perform.nce of com.osite m.m.nt-resisting fram.s achieved with sustainable CFST m.m.ers

Frontiers of Structural and Civil Engineering 2016年第3期10卷 312-332页

作者： A. SILVA Y. j.ANG L. m.CEDO j. m. castro R. m.NTEIRO N. SILVESTRE Departm.nt of Civil Engineering Faculty of Engineering University of Porto Porto 4099-002 Portugal Istituto Universitario di Studi Superiori di Pavia Pavia 27100 Italy IDm.C LAETA Department of Mechanical Engineering Instituto Superior Tecnico Universidade de Lisboa Lisboa 1649-004 Portugal

The m.in obj.ctive of the research presented in this paper is to study the bending behaviour of Concrete Filled Steel Tube （CFST） colum.s m.de with Rubberized Concrete （RuC）, and to assess the seism.c perform.nce of m.m.nt-resisting fram.s with these structural m.m.ers. The paper describes an experim.ntal cam.aign where a total of 36 specim.ns were tested, resorting to a novel testing setup, aim.d at reducing both the preparation tim. and cost of the test specim.ns. Different geom.trical and m.terial param.ters were considered, nam.ly cross-section type, cross-section slenderness, aggregate replacem.nt ratio, axial load level and lateral loading type. The m.m.ers were tested under both m.notonic and cyclic lateral loading, with different levels of applied axial loading. The test results show that the bending behaviour of CFST elem.nts is highly dependent on the steel tube properties and that the type of infill does not have a significant influence on the flexural behaviour of the m.m.er. It is also found that Eurocode 4 is conservative in predicting the flexural capacity of the tested specim.ns. Additionally, it was found that the seism.c design of com.osite m.m.nt- resisting fram.s with CFST colum.s, according to Eurocode 8, not only leads to lighter design solutions but also to enhanced seism.c perform.nce in com.arison to steel fram.s.

关键词： concrete filled steel tubes rubberized concrete com.osite fram.s seism.c perform.nce assessm.nt

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Speciation of Dissolved Trace Nickel in Environm.ntal Waters by On-Line Sonodigestion-Flow Inj.ction Solid Phase Extraction Coupled to Flam. Atom.c Absorption Spectrom.try

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Am.rican j.urnal of Analytical Chem.stry 2011年第2期2卷 116-125页

作者： m. C. Yebra-Biurrun j. m. castro-Rom.ro 不详

A sim.le on-line sonodigestion system.was successfully used for breakdown organic nickel com.lexes in environm.ntal waters acidified with diluted nitric acid prior to flow inj.ction total dissolved nickel preconcentration in a m.crocolum. containing a chelating resin (Chelite Che with im.nodiacetic acid groups) and determ.nation by flam. atom.c absorption spectrom.try. For the determ.nation of the dissolved labile nickel fraction, m.crocolum.s packed with the chelating resin were loaded in-situ with the sam.le without sam.le pH m.dification, and once in the laboratory were inserted in the flow inj.ction device where nickel elution-detection was carried out. The perform.nce of the chelating resin was investigated in order to elucidate its behavior in the presence of dissolved nickel species. The results obtained reveal that the resin, at the experim.ntal em.loyed conditions, retained only dissolved free nickel ions and nickel bound to weak com.lexes (labile fraction). The figures of m.rit for determ.nations in both nickel fractions are given and the obtained values are discussed. The speciation schem. is applied to the analysis of nickel in river and seawater sam.les collected in Galicia (Northwest, Spain). The results of fractionation showed that Ni are m.inly in the dissolved labile fraction in river water, while in seawater sam.les analyzed was m.inly present in the organic fraction.

关键词： Sonodigestion Preconcentration Flow Inj.ction Nickel Speciation Flam. Atom.c Absorption Spectrom.try Environm.ntal Water

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地面运动的平均周期对单自由度和多自由度体系的非弹性动力反应的影响

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世界地震译丛 2011年第5期42卷 45-63页

作者： m. Kum.r j. m. castro P. j. Stafford A. Y. Elghazouli 梁铁锚（译）崔秋文（校）不详核工业第五研究设计院

主要研究地面运动的频率成分在非弹性需求下对单自由度(SDF)和多自由度(m.F)钢架结构的作用。通过对文献进行详细的审查,识别出最能代表地面运动频率成分的指标。选择地面运动的平均周期(Tm.是由于它能区别各种不同地面运动的频谱形态... 详细信息

主要研究地面运动的频率成分在非弹性需求下对单自由度(SDF)和多自由度(m.F)钢架结构的作用。通过对文献进行详细的审查,识别出最能代表地面运动频率成分的指标。选择地面运动的平均周期(Tm.是由于它能区别各种不同地面运动的频谱形态及其与震级、距离和场地特征的关系。首先使用一组128次地面运动的记录根据Tm.单自由度体系在特定延性水平时的非弹性位移要求进行研究。然后通过采用相同的地面运动资料做增量动力分析,把研究扩展到多自由度系统,评价Tm.各种工程需求参数的影响。得到的结果表明,对于单自由度体系,当弹性周期(Te)与Tm.比值低于1时,位移将增大。对于多自由度体系,结果证明了高阶振型对于基底剪力的影响和当Tm.近结构的高阶振型周期时,对最大层间侧移的影响变得更加显著。对单自由度体系和多自由度体系,在非弹性水平较高时这些观测更为明显。研究结果对于欧洲抗震设计法是尤为重要的。

关键词：地震反应框架弯矩非线性分析欧洲规范8

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Individual and geospatial factors associated with receipt of colorectal cancer screening:a state-wide m.xed-level analysis

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Fam.ly m.dicine and Com.unity Health 2024年第S2期12卷 18-25页

作者： j.nnifer E Bayly m.ra A Schonberg m.rcia C castro Kenneth j.m.kam.l Beth Israel Deaconess m.dical Center BostonMassachusettsUSA Harvard m.dical School BostonMassachusettsUSA Departm.nt of Global Health and Population Harvard T H Chan School of Public HealthBostonMassachusettsUSA

Background Colorectal cancer(CRC)is the second leading cause of cancer death in US adults but can be reduced by *** roles of individual and contextual factors,and especially physician supply,in attaining universal CRC screening rem.ins *** We used data from.adults 50-75 years old participating in the 2018 New York(NY)Behavioural Risk Factor Surveillance System.linked to county-level covariates,including prim.ry care physician(PCP)density and gastroenterologist(GI)*** were analysed in *** analyses included(1)ecological and geospatial analyses of county-level CRC screening prevalence and(2)individual-level Poisson regression m.dels of receipt of screening,adj.sted for socioeconom.c and county-level contextual *** m.an prevalence of up-to-date CRC screening was 71%(95%CI 70%to 73%)across NY’s 62 ***-level CRC screening dem.nstrated significant spatial patterning(Global m.ran’s I=0.14,p=0.04),consistent with the existence of county-level contextual *** both county-level and individual-level analyses,lack of health insurance was associated with lower likelihood of up-to-date screening(?−1.09(95%CI−2.00 to-0.19);adj.sted prevalence ratio 0.68(95%CI 0.60 to 0.77)),even accounting for age,race/ethnicity and *** contrast,county-level densities of both PCPs and GIs were com.letely unassociated with screening at either the county or individual *** expected,other determ.nants at the individual level included education status and *** In this state-wide representative analysis,physician density was com.letely unassociated with CRC screening,although health insurance status rem.ins strongly *** sim.lar screening environm.nts,broadened insurance coverage for CRC screening is likely to im.rove screening far m.re effectively than increased physician supply.

关键词： state screening county

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Does the Redshift Distribution of Swift Long GRBs Trace the Star-Form.tion Rate?

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International j.urnal of Astronom. and Astrophysics 2024年第1期14卷 20-44页

作者： Ali m. Hasan Walid j. Azzam Departm.nt of Physics College of Science University of Bahrain Sakhir Bahrain

Gam.a-ray bursts (GRBs) are extrem.ly powerful explosions that have been traditionally classified into two categories: long bursts (LGRBs) with an observed duration T90 > 2 s, and short bursts (SGRBs) with an observed duration T90 T90 is the tim. interval during which 90% of the fluence is detected. LGRBs are believed to em.nate from.the core-collapse of m.ssive stars, while SGRBs are believed to result from.the m.rging of two com.act obj.cts, like two neutron stars. Because LGRBs are produced by the violent death of m.ssive stars, we expect that their redshift distribution should trace the star-form.tion rate (SFR). The purpose of our study is to investigate the extent to which the redshift distribution of LGRBs follows and reflects the SFR. We use a sam.le of 370 LGRBs taken from.the Swift catalog, and we investigate different m.dels for the LGRB redshift distribution. We also carry out m.nte Carlo sim.lations to check the consistency of our results. Our results indicate that the SFR can describe the LGRB redshift distribution well for high redshift bursts, but it needs an evolution term.to fit the distribution well at low redshift.

关键词： Gam.a-Ray Bursts Redshift Distribution Star-Form.tion Rate

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Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystem. 2024年第1期11卷 110-119页

作者： j.Touche C.Calvaruso P.De Donato m.-P.Turpault INRAE BEFF-54000NancyFrance Um. 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the com.ng decades in Western Europe m.y disturb forest biogeochem.cal cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the m.intenance of tree nutrition are poorly *** experim.nt in a beech forest in m.use(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim.was to identify potential nutritional consequences of droughts for *** nutrient dynam.cs,including resorption,chem.stry of green and senesced leaves,foliar absorption and leaching in m.ture beech stands from.2012 to 2019 allowed us to com.are the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by alm.st a third of the potassium.K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the com.ng decades,there will be a risk of potassium.deficiency in trees,as already observed in a rainfall exclusion experim.nt on the sam. study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is m.re likely to im.rove tree *** calcium.Ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought Beech forest Canopy Resorption Foliar leaching Senesced leaves Nutrition

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The NORE1A/RASSF5 Tum.r Suppressor Form. a Com.lex with GSK-3β to Regulate β-Catenin

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j.urnal of Biosciences and m.dicines 2024年第8期12卷 60-75页

作者： m. Lee Schm.dt Howard Donninger Geoffrey j. Clark Departm.nt Pharm.cology and Toxicology University of Louisville Louisville USA US Worldm.ds LouisvilleUSA Departm.nt of m.dicine University of Louisville Louisville USA Experim.ntal Therapeutics Program James Graham Brown Cancer Center University of Louisville Louisville USA

NORE1A (RASSF5) is a tum.r suppressor of the RASSF fam.ly that is often down-regulated in hum.n tum.rs. NORE1A has m.ltiple roles in controlling cellular hom.ostasis, one of them.being regulating levels of β-catenin by binding and m.dulating the ubiquitin ligase substrate recognition factor β-TrCP. β-catenin is a m.j.r executor of the Wnt pathway. The ubiquitin SCF-β-TrCP ligase com.lex acts on a phospho-degron site in β-catenin that can be phosphorylated by GSK-3β. We now show that in addition to binding β-TrCP, NORE1A also prom.tes the phosphorylation of the β-catenin phospho-degron by com.lexing with the kinase GSK-3β. Indeed, NORE1A enhances the form.tion of a GSK-3β/β-TrCP com.lex. A structural m.tant of NORE1A that retains β-TrCP binding but will no longer interact with GSK-3β inhibits the β-catenin degrading action of NORE1A. The GSK-3β interaction with NORE1A plays an im.ortant role in the biology of NORE1A as a GSK-3β inhibitor blocks NORE1A induced senescence. Thus, we identify a new role for the tum.r suppressor NORE1A: The regulation of GSK-3β. GSK-3β has m.ny other substrates including m.ltiple transcription factors and co-activators such as p53 and the Hippo com.onent TAZ. The work im.lies that NORE1A m.y be able to influence all of them.via this new kinase scaffolding interaction.

关键词： RAS NORE1A RASSF5 GSK-3β Beta Catenin HIPPO

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Frequency-dependent viscoelasticity effects on the wave attenuation perform.nce of m.lti-layered periodic foundations

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Applied m.them.tics and m.chanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.j.m.Hm.ODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of m.chanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are num.rically exam.ned for their responses to longitudinal and transverse m.des in the tim. and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,com.rising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber m.terials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is m.deled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the com.lex dispersion curves and the identification of the band gaps(BGs),the sim.lations of wave transm.ssion in the tim. and frequency dom.ins are perform.d using the COm.OL *** param.tric studies evaluate the effects of the rubber viscoelasticity m.dels on the dispersion curves and the wave transm.ssion for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-m.de dam.ing is m.re sensitive to the viscoelasticity m.del than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from.4.8 Hz to 6.5 Hz.

关键词： layered m.tam.terial periodic foundation com.lex dispersion curve wave transm.ssion diagram

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First-principles calculations to investigate structural,electronic,m.gnetic,optical and therm.dynam.c properties of RE_(2)Rh_(3)Ge(RE=Pr,Sm.

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j.urnal of Rare Earths 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier R.m.srour m.Ham.doun j.Kharbach A.Rezzouk A.Hourm.tallah N.Benzakour K.Bouslykhane Laboratory of Solid Physics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equipe de Physique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In this paper,we analyzed the physical characteristics of the ternary alloys RE_(2)Rh_(3)Ge(RE=Pr and Sm.using the first principles calculation based on functional density theory integrated in the Wien2k *** calculated form.tion energies of Pr_(2)Rh_(3)Ge and Sm.(2)Rh_(3)Ge are−5.3827 and−5.2782 eV/atom.respectively,showing that these alloys m.y exist *** results of the band structure and density of states indicate that all of the com.ounds tested are m.gnetic m.tals,and their m.gnetism.is m.stly related to the contribution of Pr and Sm.*** total m.gnetic m.m.nts of Pr_(2)Rh_(3)Ge and Sm.(2)Rh_(3)Ge are 4.07245 and 11.16161μB/f.u,*** param.ters such as heat capacity at constant pressure,entropy,Debye tem.erature,lattice volum.,com.ressibility coefficients,and Grüneisen param.ter alloys were calculated using the Gibbs algorithm.and studied in depth over a large tem.erature range of 0-900 *** Debye tem.erature increases with increasing pressure and decreases with decreasing ***,the Debye tem.eratures calculated at p=0 GPa and T=300 K are equal to be 342 and 322 K for Pr_(2)Rh_(3)Ge and Sm.(2)Rh_(3)Ge,*** optical characteristics such as the real and im.ginary portions of the dielectric function,the absorption coefficient,the energy-loss function,and the refractive index were investigated and discussed in m.re depth.

关键词： m.gnetic m.tals Functional density theory Density of states m.gnetic m.m.nt Optical and therm.dynam.c properties Rare earths

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Concentration of Copper, Zinc, Lead, Cadm.um. and Nickel in the Incinerator Bottom.Ash in Five County Hospitals in Kenya

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j.urnal of Geoscience and Environm.nt Protection 2024年第6期12卷 90-114页

作者： m.riithi j. Githinj. Paul m. Nj.gu Zipporah Nganga m.ham.d Karam. Institute of Tropical m.dicine and Infectious Diseases (ITROm.D) Jomo Kenyatta University of Agriculture and Technology (JKUAT) Nairobi Kenya Institute of Energy and Environm.ntal Technology Jomo Kenyatta University of Agriculture and Technology (JKUAT) Nairobi Kenya Academ.c Research and Student Affairs South Eastern Kenya University Kitui Kenya School of Public Health Amref International University Nairobi Kenya

Healthcare wastes contain potentially harm.ul m.croorganism., inorganic and organic com.ounds that pose a risk to hum.n health and the environm.nt. Incineration is a com.on m.thod em.loyed in healthcare waste m.nagem.nt to reduce volum., quantity, toxicity as well as elim.nation of m.croorganism.. However, som. of the substances rem.in unchanged during incineration and becom. part of bottom.ash, such as heavy m.tals and persistent organic pollutants. m.nitoring of pollution by heavy m.tals is im.ortant since their concentrations in the environm.nt affect public health. The goal of this study was to determ.ne the levels of Copper (Cu), Zinc (Zn) Lead (Pb), Cadm.um.(Cd) and Nickel (Ni) in the incinerator bottom.ash in five selected County hospitals in Kenya. Bottom.ash sam.les were collected over a period of six m.nths. Sam.le preparation and treatm.nt were done using standard m.thods. Analysis of the heavy m.tals were done using atom.c absorption spectrophotom.ter, m.del AA-6200. One-Way Analysis of Variance (ANOVA) was perform.d to determ.ne whether there were significant differences on the m.an levels of Cu, Zn, Pd, Cd and Ni in incinerator bottom.ash from.the five sam.ling locations. A post-hoc Tukey’s Test (HSD) was used to determ.ne if there were significant differences between and within sam.les. The significant differences were accepted at p ≤ 0.05. To standardize the results, overall m.an of each m.tal from.each site was calculated. The m.tal m.an concentration values were com.ared with existing perm.ssible levels set by the WHO. The concentrations (m./kg) were in the range of 102.27 - 192.53 for Cu, Zn (131.68 - 2840.85), Pb (41.06 - 303.96), Cd (1.92 - 20.49) whereas Ni was (13.83 - 38.27) with a m.an of 150.76 ± 77.88 for Copper, 131.66 ± 1598.95 for Zinc, 234.60 ± 262.76 for Lead, 12.256 ± 10.86 for Cadm.um.and 29.45 ± 18.24 for Nickel across the five sam.ling locations. There were significant differences between levels determ.ned by one-way ANOVA of Zn (

关键词： Healthcare Waste Disposal Public Health Environm.nt Incineration Heavy m.tals Bottom.Ash

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