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International journal of Geosciences 2024年第5期15卷 396-415页

作者： Heinz-jürgen brink Independent Researcher Hannover Germany

The rotation of the earth and the related length of the day (LOD) are predominantly affected by tidal dissipation through the Moon and the growth of the earth’s core. Due to the increased concentration of mass around the rotation axis of the spinning earth during the growth of the core the rotation should have been accelerated. Controversially the tidal dissipation by the Moon, which is mainly dependent on the availability of open shallow seas and the kind of Moon escape from a nearby position, acts towards a deceleration of the rotating earth. Measurements of LOD for Phanerozoic and Precambrian times open ways to solve questions concerning the geodynamical history of the earth. These measurements encompass investigations of growth patterns in fossils and depositional patterns in sediments (Cyclostratigraphy, Tidalites, Stromatolites, Rhythmites). These patterns contain information on the LOD and on the changing distance between earth and Moon and can be used as well for a discussion about the growth of the earth’s core. By updating an older paper with its simple approach as well as incorporating newly published results provided by the geoscientific community, a moderate to fast growth of the core in a hot early earth will be favored controversially to the assumption of a delayed development of the core in an originally cold earth. Core development with acceleration of earth’s rotation and the contemporaneous slowing down due to tidal dissipation during the filling of the ocean may significantly interrelate.

关键词： Length of the Day Moon Distance Phanerozoic Geodynamic Cycles Tidal Dissipation earth’s Core

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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Spherical Functions on Fuzzy Lie Group

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Advances in Pure Mathematics 2024年第4期14卷 185-195页

作者： murphy e. egwe Samuel S. Sangodele Department of Mathematics University of Ibadan Ibadan Nigeria

Let G be a locally compact Lie group and its Lie algebra. We consider a fuzzy analogue of G, denoted by called a fuzzy Lie group. Spherical functions on are constructed and a version of the existence result of the Hel... 详细信息

关键词： Fuzzy Spherical Function Fuzzy Lie Group Fuzzy Manifolds

Groupoid Approach to ergodic Dynamical System of Commutative von Neumann Algebra

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Advances in Pure Mathematics 2024年第3期14卷 167-184页

作者： Nicholas O. Okeke murphy e. egwe Physical and Mathematical Sciences Dominican University Ibadan Nigeria Department of Mathematics University of Ibadan Ibadan Nigeria

Given a compact and regular Hausdorff measure space (X, μ), with μ a Radon measure, it is known that the generalised space M(X) of all the positive Radon measures on X is isomorphic to the space of essentially bounded functions L∞(X, μ) on X. We confirm that the commutative von Neumann algebras M⊂B(H), with H=L2(X, μ), are unitary equivariant to the maximal ideals of the commutative algebra C(X). Subsequenly, we use the measure groupoid to formulate the algebraic and topological structures of the commutative algebra C(X) following its action on M(X) and define its representation and ergodic dynamical system on the commutative von Neumann algebras of M of B(H) .

关键词： Measure Groupoid Groupoid equivalence ergodic Action Convolution Algebra von Neumann Algebra Generalized Space

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

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