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基于双能CT的成像对不同经验影像医师诊断骨质疏松性椎骨压缩性骨折骨髓水肿准确度的影响:与MRI比较

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国际医学放射学杂志 2016年第5期 574-575页

作者： M.Kaup j.L.Wichmann j.e.scholtz M.Beeres W.Kromen M.H.Albrecht 樊志红 Department of Diagnostic and Interventional Radiology Clinic of the Goethe University

摘要目的探讨与MR比较,双能CT(DeCT)虚拟去钙成像是否能提高不同经验影像医师对骨质疏松病人急性胸腰椎压缩性骨折的检出率。材料与方法这项回顾性研究经本单位伦理委员会批准,所有病人签署知情同意书。49例疑为急性脊椎骨折的骨质疏松... 详细信息

摘要目的探讨与MR比较,双能CT(DeCT)虚拟去钙成像是否能提高不同经验影像医师对骨质疏松病人急性胸腰椎压缩性骨折的检出率。材料与方法这项回顾性研究经本单位伦理委员会批准,所有病人签署知情同意书。49例疑为急性脊椎骨折的骨质疏松症病人行DeCT和MR检查,得到传统线性混合能量CT和相应的虚拟去钙重建图像。5位不同经验的影像医师观察灰阶CT影像确定有无骨折及期

关键词：骨质疏松医师诊断 MRI 骨髓水肿影像医师胸腰椎压缩性骨折 CT 双能

Are hydrides under high-pressure-high-temperature superconductors?

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National Science Review 2024年第7期11卷 9-12页

作者： j.e.Hirsch Department of Physics University of California

Contrary to the current consensus, I argue that the existing evidence for high-temperature superconductivity in hydrides under high pressure is not compelling. I suggest that the focus of the field should urgently shift to establish unequivocally experimentally whether or not superconductivity in pressurized hydrides exists, instead of continuing to search for new materials that might show elusive signals of unproven superconductivity at ever higher temperatures. The implications of a negative finding for the theoretical understanding of superconductivity are discussed.

关键词： Hydrides

Malargüe Site Remediation:A Successful Solution for Uranium Mill Tailings

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原子能科学技术 2024年第10期58卷 2088-2094页

作者： BARARI e DíAZ j G GIOMIA KeMPF R A National Atomic energy Commission Av.Del Libertador 8250Ciudad Autónoma de Buenos AiresC1429BNPArgentina

Comisión Nacional de energía Atómica (CNeA) has the responsibility for restoring uranium mining facilities once the operations have ***,within its environmental Program and in compliance with its legal responsibilities,decides to implement a restoration project for all sites related to the mining and processing of uranium *** Malargüe Site is located within the Province of Mendoza in the city of Malargü*** is the first site to successfully complete its *** activities consist of relocation of tailings to an engineering *** tailings management(encapsulation) and rehabilitation of the area was finished in june *** remediation alternative for the ore tailings was selected after conducting comparative studies and submitted the project to the society for *** objective of the encapsulation of the mineral tails is to isolate them from the environment,also proceeding with the decontamination and rehabilitation of the area (landscaping,post-closure monitoring and 20 years monitoring period).encapsulation consisted of the construction of a containment cell for the mine tailings,to isolate them and prevent pollutants from entering the environment through the transfer *** clean the impacted areas,the soil was removed,it was incorporated into the encapsulation,and the filling was carried out with natural soils from the *** prevents radon transfer to the environment,as ^(222)Ra is an alpha emitter with a half-life of four days,which produces its own radioactive *** progeny are solids,and when a ^(222)Ra nucleus emits an alpha particle into the air,the resulting ^(218)Po nucleus,momentarily electrically charged,adheres to any dust *** prevents the discharge into the air containing radon and also containing dust particles charged with intensely radioactive radon *** tasks mentioned make it possible to decrease radon emanation,reduce radiological risks to the public and pre

关键词： remediation radionuclide transfer tailings encapsulation solution sustainable

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Annual variation of adult survival of a south-temperate House Wren population in Argentina

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Avian Research 2024年第2期15卷 229-237页

作者： Gustavo j.Fernandez Mariana e.Carro Paulo e.Llambías Grupo de Investigacion en ecofisiología de Fauna Silvestre INIBIOMA-CONICETAsentamiento Universitario San Martín de los Andes(AUSMA)Universidad Nacional Del ComahuePasaje de la Paz 235(8370)San Martín de los AndesNeuquenArgentina Grupo de Investigacion de Biología de Aves IADIZA CCT-MendozaUniversidad Nacional de CuyoAvenida RuizLeal s/n Parque General San Martin5500MendozaArgentina

Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population *** numerous studies on this subject in north-temperate environments,there is a lack of equivalent studies at similar latitudes in the ***,we used a 14-year dataset of capture,banding,and resighting to estimate the annual variation in the apparent adult survival probability of a south-temperate population of House Wrens(Troglodytes aedon bonariae).We evaluated temporal variation in sur-vival and the effect of environmental(climatic)and demographic variables(adult abundance,total number of fledglings produced during each breeding season)on survival *** found that the probability of adult survival decreased as the abundance of breeding adults *** density-dependent effect could be related to the resident lifestyle of southern House Wrens,which could determine an intense competition for territories and resources that ultimately would affect their survival.

关键词： Annual variation CjS Density-dependence Survival Troglodytes aedon bonariae

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Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.D.james j.e.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTeCs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTeC heterogeneity by examining the mechanisms by which mTeCs mimic the peripheral self[1].

关键词： medullary eliminate restricted

Impact of device resistances in the performance of graphene‑based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期17卷 87-97页

作者： O.Castelló Sofía M.López Baptista K.Watanabe T.Taniguchi e.Diez j.e.Velázquez-Pérez Y.M.Meziani j.M.Caridad j.A.Delgado-Notario Department of Applied Physics University of Salamanca37008 SalamancaSpain Unidad de excelencia en Luz y Materia estructurada(LUMeS) University of Salamanca37008 SalamancaSpain Research Center for electronic and Optical Materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for Materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFeTs)have demonstrated an outstanding potential for terahertz(THz)photodetection due to their fast response and *** features are essential to enable emerging THz applications,including 6G wireless communications,quantum information,bioimaging and ***,the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic *** this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFeT *** dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector,*** results can be well understood by a series resistance model,as shown by the excellent agreement found between the experimental data and theoretical *** findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词： Graphene THz Photodetector Field-effect transistor Plasmonic

Comparisons of oxbow lake fish assemblages in relation to bigheaded carp establishment in the lower White River, Arkansas

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ecological Processes 2024年第1期13卷 188-205页

作者： Michael A.eggleton Cody j.Salzmann joseph e.Kaiser Shannon C.F.Smith Department of Aquaculture and Fisheries University of Arkansas at Pine Bluff Arkansas Game and Fish Commission Virginia Institute of Marine Science

Background Since the late 1990s, bigheaded carps(largely silver carp [Hypophthalmichthys molitrix] but also bighead carp [H. nobilis]) have established throughout the lower Mississippi River basin. Using previously studied oxbow lakes in the lower White River basin, Arkansas, we compared current(2017, “post-carp” establishment) fish assemblages to historical(2002, “pre-carp” establishment) fish assemblages. Fish assemblages were comprehensively assessed using multiple gears, including boat electrofishing, mini-fyke nets, and experimental small-mesh gill *** T-tests suggested that fish assemblage indices of richness, diversity, evenness, and dominance were often greater(P e post-carp period as reflected by boat electrofishing and experimental gill nets. However, all indices were generally similar(P > 0.05) between the pre-carp and post-carp period with fish assemblages depicted using mini-fyke nets. Nonmetric multidimensional scaling analyses indicated that fish assemblages differed structurally between pre-carp and post-carp periods. Assemblage differences were linked to both small and large abundance changes for more than 20 species. Abundances of gizzard shad(Dorosoma cepedianum), emerald shiner(Notropis atherinoides), pugnose minnow(Opsopoeodus emiliae), crappies(Pomoxis spp.), bluegill(Lepomis macrochirus), orangespotted sunfish(L. humilis), and yellow bass(Morone mississippiensis) declined between the pre-carp and postcarp periods. Conversely, abundances of weed shiner(N. texanus), pallid shiner(Hybopsis amnis), longear sunfish(L. megalotis), buffalofishes(Ictiobus spp.), and gars(Lepisosteus spp.) generally increased during the same *** Although not possible to conclude assemblage shifts were entirely related to bigheaded carps due to the absence of an appropriate reference system where carps did not establish, the wide establishment of these carps is one of the most pervasive changes to have occurred in the lower White

关键词： Bigheaded carp Silver carp Aquatic nuisance species Fish assemblage Oxbow lake Large river

先进的基于图像虚拟单双能CT腹部血管成像:优化设置千电子伏特提高影像对比度

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国际医学放射学杂志 2016年第4期 461-461页

作者： M.H.Albrecht j.e.scholtz K.Hüsers M.Beeres A.M.Bucher M.Kaup 黄坤 Department of Diagnostic and Interventional Radiology University Hospital Frankfurt

摘要目的比较采用先进的图像虚拟单能成像重建算法(Mono+)的腹部双能CT血管成像(De-CTA)与标准的双能CT血管成像的定量影像特征参数。方法行腹部De-CTA的55例病人[男36例;平均年龄(64.2±12.7)岁]被纳入研究。

关键词：双能腹部血管成像躯干脾动脉肝总动脉 CT CNR Mono CTA