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国际医学放射学杂志 2021年第5期 612-613页

作者： L.j.Oostveen F.j.A.Meijer F.de Lange e.j.smit S.A.Pegge S.C.A.Steens 余子意

摘要目的在大脑平扫CT(NCCT)中,对比商用的深度学习重建算法(DLR)、混合迭代重建(Hybrid-IR)算法和基于模型的迭代重建(MBIR)算法的影像质量和重建时间。方法

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《耳鸣患者皮层和皮层下听觉区超高场MRI的研究》摘译

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听力学及言语疾病杂志 2024年第4期32卷 384-385页

作者：申丽君文之(摘译) 曹永茂(审校) Berlot e Arts R smit j 武汉大学人民医院耳鼻咽喉头颈外科武汉430060 武汉大学人民医院放射科

耳鸣研究的难点之一在于难以将耳鸣感知与其他合并症进行区分,例如听力损失和声音耐受性降低(DST)经常同时出现。在研究耳鸣动物模型时,区分起来尤其困难。对耳鸣患者研究时往往未能充分控制混杂因素。最近的研究表明,在仔细控制听力损... 详细信息

耳鸣研究的难点之一在于难以将耳鸣感知与其他合并症进行区分,例如听力损失和声音耐受性降低(DST)经常同时出现。在研究耳鸣动物模型时,区分起来尤其困难。对耳鸣患者研究时往往未能充分控制混杂因素。最近的研究表明,在仔细控制听力损失和DST后,耳鸣组和对照组之间先前存在的差异消失了。另一个难点是非侵入性测量技术的空间分辨率有限。为了检测诸如内侧膝状体(MGB)和下丘(IC)等皮层下听觉结构的频率响应特异性,需要高空间分辨率。由于这些结构仅为几立方毫米(例如内侧膝状体为4 mm×5 mm×4.5 mm),常规磁场(3T及以下)下的功能磁共振成像(fMRI)的空间分辨率为2 mm×2 mm×2 mm,无法检查这些微小结构中频率响应的特异性。7T的超高场(UHF)磁共振成像(MRI)提供的灵敏度有足够的分辨率显示微小的听觉皮层下结构的响应,便于详细描述其频率拓扑。本实验研究旨在UHF-MRI应用于耳鸣患者探索耳鸣的机制。

关键词：内侧膝状体立方毫米耳鸣患者混杂因素听力损失皮层下高空间分辨率动物模型

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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

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

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National Science Review 2024年第07期 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.

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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

exploring the effects of anthropogenic disturbance on predator inspection activity in Trinidadian guppies

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Current Zoology 2024年第1期70卷 109-111页

作者： Alix j.P Brusseau Laurence e.A.Feyten Adam L.Crane Grant e.Brown Department of Biology Concordia UniversityMontrealQCH4B 1R6Canada Department of Biomedical Sciences WCVMUniversity of SaskatchewanSaskatoonSKCanada

Prey animals are often faced with uncertainty due to having imperfect information regarding current local conditions,including predation risks and the availability of reliable foraging opportunities(Dall 2010).As this uncertainty increases,the probability of making costly behavioral errors also increases,leading to more risk averse behavioral tactics(Feyten et al.2019).For example,Trinidadian guppies Poecilia reticulata are far more risk averse when faced with multiple unknown sources of risk assessment information than when faced with a mix of known and unknown cues(Feyten et al.2019).Prey can reduce uncertainty by gathering and integrating private and social information regarding current risk levels within microhabitats(Dall 2010;Munoz and Blumstein 2012).

关键词： human disturbance information availability information reliability predator-prey interactions risk assessment uncertainty

Malargüe Site Remediation: A Successful Solution for Uranium Mill Tailings

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原子能科学技术 2024年

作者： BARARI e DíAZ j G GIOMIA KeMPF R A National Atomic energy Commission Av.Del Libertador 8250 Ciudad Autónoma de Buenos AiresC1429BNP Argentina

Comisión Nacional de energía Atómica(CNeA) has the responsibility for restoring uranium mining facilities once the operations have finished. CNeA, 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 ores. The Malargüe Site is located within the Province of Mendoza in the city of Malargüe. It is the first site to successfully complete its remediation. The activities consist of relocation of tailings to an engineering repository. The tailings management(encapsulation) and rehabilitation of the area was finished in june 2017. The remediation alternative for the ore tailings was selected after conducting comparative studies and submitted the project to the society for consideration. The 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 routes. To 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 222Ra is an alpha emitter with a half-life of four days, which produces its own radioactive progeny. Radon progeny are solids, and when a 222Ra nucleus emits an alpha particle into the air, the resulting 218Po nucleus, momentarily electrically charged, adheres to any dust particle. Remediation prevents the discharge into the air containing radon and also containing dust particles charged with intensely radioactive radon progeny. The tasks mentioned make it possible to decrease radon emanation, reduce radiological risks to the

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源自大脑CT灌注数据的非时变重建的高质量CT血管成像

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国际医学放射学杂志 2012年第3期 284-284页

作者： e.j.smit e.Vonken I.C.van der Schaaf A.M.Mendrik j.W.Dankbaar A.D.Horsch 范璐 Department of Radiology University Medical Center UtrechtHeidelberglaan 100PO Box 855003508 GA Utrechtthe Netherlands

目的提出一个简单且稳定的,由CT灌注数据重建出高质量CT血管影像的成像技术,并与当前使用的CT血管成像技术进行对比。材料与方法本研究为包括连续25例脑卒中病人在内的回顾性研究,经学术审查委员会批准,通过用先前时间滤过的时间敏感技... 详细信息

目的提出一个简单且稳定的,由CT灌注数据重建出高质量CT血管影像的成像技术,并与当前使用的CT血管成像技术进行对比。材料与方法本研究为包括连续25例脑卒中病人在内的回顾性研究,经学术审查委员会批准,通过用先前时间滤过的时间敏感技术由CT灌注数据产生

关键词：血管成像滤过 CT 动脉期