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Long-term monitoring of cycles in Clethrionomys rutilus in the Yukon boreal forest

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Integrative Zoology 2024年第1期19卷 27-36页

作者： Charles j.k.EBS Alice j.k.NNEY B.Scott GILBERT Rudy BOONSTRA Department of Zoology University of British ColumbiaVancouverBritish ColumbiaCanada Renewable Resources Management Program Yukon UniversityWhitehorseYukonCanada Department of Biological Sciences University of Toronto ScarboroughTorontoOntarioCanada

Baseline studies of small rodent populations in undisturbed ecosystems are *** report here 50 years of mon-itoring and experimentation in Yukon of a dominant rodent species in the North American boreal forest,the red-backed vole Clethrionomys *** voles breed in summer,weigh 20–25 g,and reach a maximum density of 20 to 25 per *** populations have shown consistent 3–4-year cycles for the last 50 years with the only change being that peak densities averaged 8/ha until 2000 and 18/ha since that *** the last 25 years,we have measured food resources,predator numbers,and winter weather,and for 1-year social interactions,to estimate their contribution to changes in the rate of summer increase and the rate of overwinter *** these potential limiting factors could contribute to changes in density,and we measured their relative contributions statistically with multiple *** rate of winter decline in density was related to both food supply and winter *** rate of summer increase was related to summer berry crops and white spruce cone *** measure of predator numbers was related to winter or summer changes in vole *** was a large signal of climate change effects in these *** is no density dependence in summer population growth and only a weak one in winter population *** of our results provide a clear understanding of what generates 3–4-year cycles in these voles,and the major missing piece may be an understanding of social interactions at high density.

关键词： boreal forest climate change density dependence population cycles predation winter severity

Therapeutic and regenerative potential of different sources of mesenchymal stem cells for cardiovascular diseases

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BIOCELL 2024年第4期48卷 559-569页

作者： YARA ALZGHOUL HALA j.BANI ISSA AHMAD k.SANAjLEH TAQWA ALABDUH FATIMAH RABABAH MAHA AL-SHDAIFAT EjLAL ABU-EL-RUB FATIMAH ALMAHASNEH RAMADA R.kHASAWNEH AYMAN ALZU’BI HUTHAIFA MAGABLEH Department of Basic Medical Sciences Faculty of MedicineYarmouk UniversityIrbidJordan

Mesenchymalstemcells(MSCs)*** the internal cardiac microenvironment to facilitate their immunomodulatory and differentiation abilities,which are essential to restore heart *** can be easily isolated from different sources,including bone marrow,adipose tissues,umbilical cord,and dental *** from various sources differ in their regenerative and therapeutic abilities for cardiovascular *** this review,we will summarize the therapeutic potential of each MSC source for heart diseases and highlight the possible molecular mechanisms of each source to restore cardiac function.

关键词： Bone marrow mesenchymal stem cells Adipose tissue mesenchymal stem cells Dental pulp stem cells Umbilical cord mesenchymal stem cells Cardiomyocytes Regeneration Myocardial infarction Mesenchymal stem cells Differentiation Immunomodulation

The Generalized Stackelberg Equilibrium of the Two-Person Stopping Game

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journal of the Operations Research Society of China 2024年第1期12卷 155-168页

作者： Marek Skarupski krzysztof j.Szajowski Faculty of Pure and Applied Mathematics Wroclaw University of Science and Technology50-370WrocƚawDolonoslaskiePoland

In modeling the bilateral selection of states of the process,Dynkin(Dokl Akad Nauk USSR 185:241–288,1969)proposed a two-person game in which players use stopping moments as *** purpose of this work is to present a model of the game in which the players have different information about the process itself,as well as various laws to stop the process and accept its *** game model uses the stochastic process apparatus,in particular,the ability to create different filters for the same *** sets of stopping moments based on different filters are not identical,which allows us to model different sets of strategies for *** show that the follower,by observing the behavior of a rational leader,can recover information that is lost due to the lack of complete observation of the state of the *** the competition of two opponents for the maximum of the ***,one of whom has access to full information and the other only knows their relative ranks,we found the generalized Stackelberg *** the priority of a player observing the relative ranks is less than 50%,then that player modifies his strategy based on the behavior of the second *** a player with full information,information about the behavior of the player observing the relative ranks is useless.

关键词： No-zero-sum game Optional stopping Equilibrium Filtration

Extracellular vesicles and angiotensin-converting enzyme 2 in COVID-19 disease

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作者： (英)j.k. 罗琳

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BIOCELL 2024年第1期48卷 1-8页

作者： YU LIU ROBERT j.k.SPER NATALIE j.S.CHOI Department of Family and Community Medicine Northwestern University Feinberg School of MedicineChicagoIllinois

Extracellular vesicles(EVs)are membranous vesicular structures released from almost all eukaryotic cell types under different physiological or pathological *** evidence demonstrates that EVs can serve as mediators of intercellular communication between donor and recipient cells or microorganism-infected and noninfected *** disease 2019(COVID-19)disease is caused by infection of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)of host cells in the respiratory system and various extra-pulmonary tissue/organs,resulting in complications of multiple organ *** the cell surface receptor,angiotensin-converting enzyme 2(ACE2)mediates cellular entry of SARS-CoV-2 into the host cells in patients with *** studies have found that ACE2 can be released with EVs,which have been shown to interfere with the entry of the virus into host cells and thus may be involved in COVID-19 *** addition,ACE2,neprilysin(NEP),and thimet oligopeptidase(TOP)are the key enzymes that regulate angiotensin metabolism by converting angiotensin II or angiotensin I to angiotensin 1-7,the latter of which has protective effects in counterbalancing the harmful effects of angiotensin II in COVID-19 *** review summarizes the recent research progress regarding EV-associated ACE2,NEP,and TOP and the perspectives of their potential involvement in the pathophysiology of COVID-19 disease.

关键词： Extracellular vesicles COVID-19 Angiotensin converting enzyme 2 Thimet oligopeptidase

Invasive ant learning is not affected by seven potential neuroactive chemicals

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Current Zoology 2024年第1期70卷 87-97页

作者： Henrique Galante Tomer j.Czaczkes Department of Zoology and Evolutionary Biology Animal Comparative Economics LaboratoryUniversity of Regensburg93053 Regensburg Germany

Argentine ants Linepithema humile are one of the most damaging invasive alien species *** or disrupting cognitive abilities,such as learning,has the potential to improve management efforts,for example by increasing preference for a bait,or improving ants'ability to learn its characteristics or ***-feeding insects are often the victims of psychoactive manipulation,with plants lacing their nectar with secondary metabolites such as alkaloids and non-protein amino acids which often alter learning,foraging,or ***,the effect of neuroactive chemicals has seldomly been explored in ***,we test the effects of seven potential neuroactive chemicals-two alkaloids:caffeine and nicotine;two biogenic amines:dopamine and octopamine,and three nonprotein amino acids:β-alanine,GABA and taurineon the cognitive abilities of invasive *** using bifurcation *** results confirm that these ants are strong associative learners,requiring as little as one experience to develop an ***,we show no short-term effect of any of the chemicals tested on spatial learning,and in addition no effect of caffeine on short-term olfactory *** lack of effect is surprising,given the extensive reports of the tested chemicals affecting learning and foraging in *** mismatch could be due to the heavy bias towards bees in the literature,a positive result publicationbias,ordifferences inmethodology.

关键词： associativelearning caffeine memory neuroactivechemicals

Resistive field generation in intense proton beam interaction with solid targets

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作者： (英)j.k. 罗琳

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Matter and Radiation at Extremes 2024年第1期9卷 35-43页

作者： W.Q.Wang j.j.Honrubia Y.Yin X.H.Yang F.Q.Shao Department of Physics National University of Defense TechnologyHunanChina ETSI Aeronáutica y del Espacio Universidad Politécnica de MadridMadridSpain Department of Nuclear Science and Technology National University of Defense TechnologyHunanChina

The Brown-Preston-Singleton(BPS)stopping power model is added to our previously developed hybrid code to model ion beam-plasma *** simulations show that both resistive field and ion scattering effects are important for proton beam transport in a solid target,in which they compete with each *** the target is not completely ionized,the self-generated resistive field effect dominates over the ion scattering ***,when the target is completely ionized,this situation is ***,it is found that Ohmic heating is important for higher current densities and materials with high *** energy fraction deposited as Ohmic heating can be as high as 20%-30%.Typical ion divergences with half-angles of about 5°-10°will modify the proton energy deposition substantially and should be taken into account.

关键词： interaction beam intense

Effects of Current Stressing on Shear Properties of Sn-3.8Ag-0.7Cu Solder joints

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journal of Materials Science & Technology 2010年第8期26卷 737-742页

作者： X.j. Wang Q.L. Zeng Q.S. Zhu Z.G. Wang j.k. Shang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Department of Materials Science and Engineering University of Illinois at Urbana-Champaign Urbana IL 61801 USA

Effects of electromigration on microstructure, shear strength, and fracture behavior of solder joints were investigated by single-ball shear samples of eutectic Sn-3.8Ag-0.7Cu （SAC） joined by Cu plates at two sides. The electromigration tests were conducted at a current density of about 1.1×10^3 A/cm2 and a working temperature of about 83℃. The results showed that the shear strength and flow stress decreased greatly after current stressing. Such a decrease was associated with no significant loss of the fracture strain at short electromigration but a great reduction in the fracture strain after long-term current stressing. The variation of the fracture strain with the electromigration time was shown to result from the shift of the fracture surface from the center of the solder towards the intermetallic compound （IMC） interface at the cathode.

关键词： Strength Fracture strain Voids Solder