检索结果-南通市图书馆

维普期刊数据库

Insm1:orchestrating cellular mimicry in the thymus medulla

在线全文

学校读者我要写书评

暂无评论

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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.

关键词：

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

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

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

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

关键词：

A Systematic Review of Computer Vision Techniques for Quality Control in end-of-Line Visual Inspection of Antenna Parts

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第8期80卷 2387-2421页

作者： Zia Ullah Lin Qi e.j.Solteiro Pires Arsénio Reis Ricardo Rodrigues Nunes School of electrical and Information engineering Zhengzhou UniversityZhengzhou450001China School of Science and Technology Universidade de Trás-os-Montes e Alto DouroVila Real5000-801Portugal

The rapid evolution of wireless communication technologies has underscored the critical role of antennas in ensuring seamless *** defects,ranging from manufacturing imperfections to environmental wear,pose significant challenges to the reliability and performance of communication *** review paper navigates the landscape of antenna defect detection,emphasizing the need for a nuanced understanding of various defect types and the associated challenges in visual *** review paper serves as a valuable resource for researchers,engineers,and practitioners engaged in the design and maintenance of communication *** insights presented here pave the way for enhanced reliability in antenna systems through targeted defect detection *** this study,a comprehensive literature analysis on computer vision algorithms that are employed in end-of-line visual inspection of antenna parts is *** PRISMA principles will be followed throughout the review,and its goals are to provide a summary of recent research,identify relevant computer vision techniques,and evaluate how effective these techniques are in discovering defects during *** contains articles from scholarly journals as well as papers presented at conferences up until june *** research utilized search phrases that were relevant,and papers were chosen based on whether or not they met certain inclusion and exclusion *** this study,several different computer vision approaches,such as feature extraction and defect classification,are broken down and ***,their applicability and performance are *** review highlights the significance of utilizing a wide variety of datasets and measurement *** findings of this study add to the existing body of knowledge and point researchers in the direction of promising new areas of investigation,such as real-time inspection systems and multispectral *** review,on its whole,of

关键词： Computer vision end-of-line visual inspection of antenna parts machine learning algorithms image processing techniques deep learning models

Physical activity volume,frequency,and intensity:Associations with hypertension and obesity over 21 years in Australian women

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

journal of Sport and Health Science 2024年第5期13卷 631-641页

作者： Gregore I.Mielke Ding Ding Shelley e.Keating Bruno P.Nunes Ruth Brady Wendy j.Brown School of Public Health The University of QueenslandBrisbaneQLD 4006Australia Sydney School of Public Health Faculty of Medicine and HealthThe University of SydneySydneyNSW 2006Australia The Charles Perkins Centre The University of SydneySydneyNSW 2006Australia School of Human Movement and Nutrition Sciences The University of QueenslandBrisbaneQLD 4072Australia School of Nursing Federal University of PelotasPelotasRio Grande do Sul 96010-610Brazil Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4226Australia

Background:Optimal patterns of accrual of recommended levels of physical activity(PA)for prevention of hypertension and obesity are not *** overall aim of this study was to investigate whether different patterns of accumulation of PA are differentially associated with hypertension and obesity in Australian women over 21 ***,we investigated whether,for the same weekly volume of PA,the number of sessions(frequency)and vigorousness of PA(intensity)were associated with a reduction in the occurrence of hypertension and obesity in ***:Data from the 1973-1978 and 1946-1951 cohorts of the Australian Longitudinal Study on Women's Health were analyzed(n=20,588;12%-16%with a Bachelor's or higher degree).Self-reported PA,hypertension,height,and weight were collected using mail surveys every 3 years from 1998/2000 to 2019/*** estimating equation models with a 3-year lag model were used to investigate the association of PA volume(metabolic equivalent min/week)(none;33-499;500-999;≥1000,weekly frequency(none;1-2 times;3-4times;5-7 times;≥8 times),and the proportion of vigorous PA to total volume of PA(none;0%;1%-33%;34%-66%;67%-100%)with odds of hypertension and obesity from 2000 to ***:The cumulative incidence of hypertension was 6%in the 1973-1978 and 23%in the 1946-1951 cohort;27%of women in the 1973-1978;and 15%in the 1946-1951 cohort developed obesity over the ***,a higher volume of PA was associated with reduced odds of hypertension and *** the volume of PA was considered,the odds of hypertension did not vary according to the frequency or intensity of ***,increased proportion of vigorous PA to the total volume of PA was associated with a small additional reduction in the risk of obe ***:PA volume appears to be more important than the pattern of accumulation for the prevention of hypertension and *** more sessions,particularly of vigorous-intensity PA,may provide extr

关键词： Physical activity Frequency Intensity Incidences epidemiology Women

维普期刊数据库

Cavity-agnostic acoustofluidic manipulations enabled by guided flexural waves on a membrane acoustic waveguide actuator

在线全文

学校读者我要写书评

暂无评论

Microsystems & Nanoengineering 2024年第2期10卷 153-171页

作者： Philippe Vachon Srinivas Merugu jaibir Sharma Amit Lal eldwin j.Ng Yul Koh joshua e.-Y.Lee Chengkuo Lee Department of electrical and Computer engineering National University of SingaporeSingaporeSingapore Institute of Microelectronics Agency for ScienceTechnology and Research(A*STAR)SingaporeSingapore SonicMeMS Laboratory School of Electrical and Computer EngineeringCornell UniversityIthacaNYUSA School of electrical and Data engineering University of Technology SydneyUltimoNSWAustralia

This article presents an in-depth exploration of the acoustofluidic capabilities of guided flexural waves(GFWs)generated by a membrane acoustic waveguide actuator(MAWA).By harnessing the potential of GFWs,cavity-agnostic advanced particle manipulation functions are achieved,unlocking new avenues for microfluidic systems and lab-on-a-chip *** localized acoustofluidic effects of GFWs arising from the evanescent nature of the acoustic fields they induce inside a liquid medium are numerically investigated to highlight their unique and promising *** traditional acoustofluidic technologies,the GFWs propagating on the MAWA’s membrane waveguide allow for cavity-agnostic particle manipulation,irrespective of the resonant properties of the fluidic ***,the acoustofluidic functions enabled by the device depend on the flexural mode populating the active region of the membrane *** demonstrations using two types of particles include in-sessile-droplet particle transport,mixing,and spatial separation based on particle diameter,along with streaming-induced counter-flow virtual channel generation in microfluidic PDMS *** experiments emphasize the versatility and potential applications of the MAWA as a microfluidic platform targeted at lab-on-a-chip development and showcase the MAWA’s compatibility with existing microfluidic systems.

关键词： waveguide fluid cavity