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Four late-type Galaxies with Double radio lobes and Properties of Such Galaxies

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research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： Z.S.Yuan X.Y.Gao Z.l.Wen J.l.Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-type galaxies is not fully *** samples are desired for a thorough investigation and *** utilizing the optical data from the newly released Dark Energy Spectroscopic Instrument imaging surveys and the radio sources from the NrAO VlA Sky Survey and the Faint Images of the radio Sky at Twenty-centimeter,we identify four late-type Galaxies with double radio lobes(la Grls):J0217-3645,J0947+6220,J1412+3723 and J1736+*** previously known la Grls,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host ***(25/35)la Grls belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red *** find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio ***,the majority(31/36)of la Grls are either located in a galaxy group or displaying a disturbed *** suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies

A landscape persistence-based methodological framework for assessing ecological stability

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Environmental Science and Ecotechnology 2024年第1期17卷 31-39页

作者： Da lü Yihe lü Guangyao Gao Siqi Sun Yi Wang Bojie Fu State Key laboratory of Urban and regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesPO Box 2871Beijing100085China University of Chinese Academy of Sciences Beijing100049China

Ecological stability is a critical factor in global sustainable development,yet its significance has been *** we introduce a landscape-oriented framework to evaluate ecological stability in the Qingzang Plateau(QP).Our findings reveal a medium-high stability level in the QP,with minimal changes over recent *** driving factors vary across landscape types,with climate and anthropogenic factors emerging as crucial *** anthropogenic factors are strong but unstable due to policy changes and economic development,climatic factors exert a consistent *** on our results,we propose site-specific ecological conservation and restoration *** ecological stability assessment framework provides a practical tool to understand the link between environmental conditions and ecosystems.

关键词： Ecological stability assessment framework landscape changes Nature conservation and ecological restoration Nature-based solutions Qingzang Plateau

Sex-specific life-history trait expression in hybrids of a cave- and surface-dwelling fish (Poecilia mexicana, Poecilidae)

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Current Zoology 2024年第4期70卷 421-429页

作者： rüdiger riesch luis r.Arriaga Ingo Schlupp Department of Biological Sciences Royal Holloway University of LondonEghamTW20 OEXUK CEFE CNRSUnivMontpellierEPHEIRDMontpellierFrance Department of Biology University of OklahomaNormanOK 73019USA

Evaluating the fitness of hybrids can provide important insights into genetic differences between species or diverging *** focused on surface-and cave-ecotypes of the widespread Atlantic molly Poecilia mexicana and raised F1 hybrids of reciprocal crosses to sexual maturity in a common-garden *** were reared in a fully factorial 2 x 2 design consisting of lighting(light ***)and resource availability(high *** food).We quantified survival,ability to realize their full reproductive potential(i.e.,completed maturation for males and 3 consecutive births for females)and essential life-history *** to the performance of pure cave and surface fish from a previous experiment,F1s had the highest death rate and the lowest proportion of fish that reached their full reproductive *** also uncovered an intriguing pattern of sex-specific phenotype expression,because male hybrids expressed cave molly life histories,while female hybrids expressed surface molly life *** results provide evidence for strong selection against hybrids in the cave molly system,but also sug-gest a complex pattern of sex-specific(opposing)dominance,with certain surface molly genes being dominant in female hybrids and certain cavemollygenes beingdominant in malehybrids.

关键词： dominance life-history evolution local adaptation postzygotic isolation selection against hybrids.

Optimal Control of Service rates of Discrete-Time(s,Q)Queueing-Inventory Systems with Finite Buffer

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 261-280页

作者： l.Iniya B.Sivakumar G.Arivarignan School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a Bernoulli process and the service time for the customers are *** the buffer size attains its maximum,any arriving new customers are considered to be *** customers are served one by one according to FCFS rule and each customers request random number of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main objectives of this article are to determine the service rates to be employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed buffer size and to minimize the expected waiting time for a fixed inventory level and fixed buffer *** problems are modelled as Markov decision *** establish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the behaviour of the model.

关键词： Queueing-inventory system discrete time batch demand-Markov decision process

research of surface-enhanced raman scattering on Ag@PMBA@C@Au hybrid nanoparticles

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Optoelectronics letters 2024年第2期20卷 65-69页

作者： TAN Enzhong lÜ Suye liberal Study College Beijing Institute of Petrochemical TechnologyBeijing 102617China

Monodispersed, biocompatible, and readily-functionalized hybrid reporter-embedded core-shell nanopartilces(NPs) have been prepared in a simple route. This composite offers a potential platform for immunochemical detection using surface-enhanced raman scattering(SErS) due to their high sensitivity, good stability and biocompatiblity. This also provides a new platform for insight into SErS enhancement mechanism.

关键词： mechanism. readily SErS

Cognitive function among military veterans with STEM occupations

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Military Medical research 2024年第2期11卷 308-310页

作者： Justin T.McDaniel Kevin N.Hascup Erin r.Hascup Ugochukwu G.Ezigbo Amanda M.Weidhuner Harvey Henson David l.Albright Dale and Deborah Smith Center for Alzheimer's research and trEatment(CArE) Southern Illinois University School of MedicineSpringfieldIL 62794USA STEM Education research Center Southern Illinois UniversityCarbondaleIL 62901USA Department of Political Science The University of AlabamaTuscaloosaAL 35487USA

Dear Editor,There is limited research on the relationship between science,technology,engineering,and mathematics(STEM)occupational history and cognitive function in later life,especially among military veterans,who may be at greater risk for later-life cognitive *** study examines a nationally representative sample of military veterans to address this gap in knowledge.

关键词： Alzheimer's disease Veterans Science technology engineering and mathematics(STEM) Animal fluency test Dementia

Investigation of the effects of radial clearance on the screw conveyor performances for different inclinations

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Particuology 2024年第9期92卷 72-80页

作者： Berna Bolat Birgül Aşçıoğlu Temiztaş Enes Sezer Department of Mechanical Engineering Yıldız Technical University34349BeşiktaşİstanbulTurkey

Screw conveyors are widely used for bulk material *** study investigates the critical role of radial clearance,the gap between the screw and the conveyor body,on performance across various inclination *** Discrete Element Method(DEM)is employed to analyze the effects of different radial clearances on conveyor performance for concrete aggregate and sand as bulk *** efficiencies and capacity losses serve as key performance indicators,quantitatively assessed for each radial clearance and inclination *** validation is conducted to corroborate the *** the study,the optimal radial clearance was identified as 1.5 to 3 times of the particle *** optimal clearance minimizes the material jamming and increases the performance for screw conveyors with different inclinations and bulk material types as a result.

关键词： Screw conveyors radial clearance Discrete element method(DEM) Volumetric efficiency Conveyor performance

Changes in snow cover extent in the Central Taurus Mountains from 1981 to 2021 in relation to temperature, precipitation, and atmospheric teleconnections

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Journal of Mountain Science 2024年第1期21卷 49-67页

作者： Ecmel ErlAT Fulya AYDIN-KANDEMİr Department of Geography Ege UniversityIzmir 35100Türkiye Climate Change and Zero Waste Department Antalya Metropolitan MunicipalityAntalya 07310Türkiye Hydropolitics Association Ankara 06680Türkiye

The snow cover over the Taurus Mountains affects water supply, agriculture, and hydropower generation in the region. In this study, we analyzed the monthly Snow Cover Extent(SCE) from November to April in the Central Taurus Mountains(Bolkar, Aladaglar, Tahtali and Binboga Mountains) from 1981 to 2021. linear trends of snow cover season(November to April) over the last 41 years showed decreases in SCE primarily at lower elevations. The downward trend in SCE was found to be more pronounced and statistically significant for only November and March. SCE in the Central Taurus Mountains has declined about-6.3% per decade for 2500-3000 m in November and about-6.0% per decade for 1000-1500 m and 3000+ m in March over the last 41 years. The loss of SCE has become evident since the 2000s, and the lowest negative anomalies in SCE have been observed in 2014, 2001, and 2007 in the last 41 years, which are consistent with an increase in air temperature and decreased precipitation. SCE was correlated with both mean temperature and precipitation, with temperature having a greater relative importance at all elevated gradients. results showed that there is a strong linear relationship between SCE and the mean air temperature(r =-0.80) and precipitation(r = 0.44) for all elevated gradients during the snow season. The Arctic Oscillation(AO), the North Atlantic Oscillation(NAO), and the Mediterranean Oscillation(MO) winter indices were used to explain the year-to-year variability in SCE over the Central Taurus Mountains. The results showed that the inter-annual variability observed in the winter SCE on the Central Taurus Mountains was positively correlated with the phases of the winter AO, NAO and MO, especially below 2000 m elevation.

关键词： Snow cover extent Atmospheric teleconnection Central Taurus Mountains Air temperature and precipitation Geographic Information Systems Türkiye

Mechanics and physics under supergravity conditions

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Acta Mechanica Sinica 2024年第6期40卷 1-2页

作者： Chaofeng lü Chao Sun Shengqiang Cai Faculty of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China New Cornerstone Science laboratory Center for Combustion EnergyDepartment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Department of Mechanical and Aerospace Engineering University of CaliforniaSan DiegoLa Jolla CA 92093USA

"Supergravity"refers to the conditions where the effective gravity is greater than that of *** conditions are generally relevant to stellar evolution,geophysical movement,astrophysical flows,and *** also frequently occur in various engineering scenarios involving acceleration,such as the launch of space shuttles,operation of rotor engines,impacts and explosions,chemical separation processes,and overloaded testing *** is already demonstrated in physiological experiments that living organisms of animals or plants could be damaged,either temporarily or permanently,when subjected to *** create supergravity conditions for scientific research on the Earth,centrifugal equipment or rapidly rotating devices are omnipresent in various fields,such as aerospace engineering,geophysical science,chemical and biomedical engineering,nuclear engineering,rotating flows,and physical modeling tests.

关键词： geophysical Earth stellar