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The role of male contest competition over mates in speciation

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Current Zoology 2012年第3期58卷 493-509页

作者： anna QVARNSTROM Niclas VALLIN Andreas RUDH Animal Ecology/Department of Ecology and Genetics Evolutionary Biology Centre Uppsala University Norbyv~gen 18DSE-752 36 Uppsala Sweden

Research on the role of sexual selection in the speciation process largely focuses on the diversifying role of mate choice. In particular, much attention has been drawn to the fact that population divergence in mate choice and in the male traits subject to choice directly can lead to assortative mating. However, male contest competition over mates also constitutes an important mechanism of sexual selection. We review recent empirical studies and argue that sexual selection through male contest competition can affect speciation in ways other than mate choice. For example, biases in aggression towards similar competitors can lead to disruptive and negative frequency-dependent selection on the traits used in contest competition in a similar way as competition for other types of limited resources. Moreover, male contest abilities often trade-off against other abilities such as parasite resistance, protection against predators and general stress tolerance. Populations experiencing different ecological condi- tions should therefore quickly diverge non-randomly in a number of traits including male contest abilities. In resource based breeding systems, a feedback loop between competitive ability and habitat use may lead to further population divergence. We discuss how population divergence in traits used in male contest competition can lead to the build up of reproductive isolation through a number of different pathways. Our main conclusion is that the role of male contest competition in speciation remains largely scientifically unexplored [Current Zoology 58 （3）： 493-509, 2012].

关键词： Male-male competition Sexual selection Speciation Resource based breeding systems Contest competition Population divergence Reproductive isolation

Biological significance of RNA-seq and single-cell genomic research in woody plants

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Journal of Forestry Research 2019年第5期30卷 1555-1568页

作者： Wei Tang anna Y.Tang College of Arts and Science East Carolina UniversityGreenvilleNC 27858USA University of North Carolina at Chapel Hill 101 Stadium DriveChapel HillNC 27514USA

RNA-seq and single-cell genomic research emerge as an important research area in the recent years due to its ability to examine genetic information of any number of single cells in all living *** knowledge gained from RNA-seq and single-cell genomic research will have a great impact in many aspects of plant *** this review,we summary and discuss the biological significance of RNA-seq and single-cell genomic research in plants including the single-cell DNA-sequencing,RNA-seq and single-cell RNA sequencing in woody plants,methods of RNA-seq and single-cell RNA-sequencing,single-cell RNA-sequencing for studying plant development,and single-cell RNA-sequencing for elucidating cell type *** will focus on RNA-seq and single-cell RNA sequencing in woody plants,understanding of plant development through single-cell RNAsequencing,and elucidation of cell type composition via single-cell *** presented in this review will be helpful to increase our understanding of plant genomic research in a way with the power of plant single-cell RNA-sequencing analysis.

关键词： Cell type composition Genomics Plant development Single-cell RNA-sequencing methods

Secondary release of the peripheral nerve with autologous fat derivates benefits for functional and sensory recovery

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Neural Regeneration Research 2021年第5期16卷 856-864页

作者： Natalia E.Krzesniak anna Sarnowska anna Figiel-Dabrowska Katarzyna Osiak Krystyna Domanska-Janik Bartłomiej H.Noszczyk Department of Plastic and Reconstructive Surgery Center of Postgraduate Medical EducationProf.W.Orlowski Memorial HospitalWarsawPoland 2Mossakowski Medical Research CenterPolish Academy of SciencesWarsawPoland

The reconstruction of nerve continuity after traumatic nerve injury is the gold standard in hand ***,tension-free,end-to-end nerve suture ensures the best *** recovery is mostly promising;however,in a few cases,insufficient outcomes in motor or sensory function are ***-and extra-fascicular scarring accompanies the nerve regeneration process and limits final *** nerve release in those cases is ***,scarring recurrence cannot be eliminated after secondary revision and *** supportive influences of mesenchymal stem cells in the process of nerve regeneration were observed in many preclinical ***,a limited number of studies in humans have analyzed the clinical usage of mesenchymal stem cells in peripheral nerve reconstruction and *** objective of this study was to evaluate the effects of undifferentiated adipose-derived stromal/stem cell injection during a last-chance surgery(neurolysis,nerve release)on a previously reconstructed *** patients(one female,two males;mean age 59±4.5 years at the time of injury),who experienced failure of reconstructions of median and ulnar nerves,were included in this *** the revision surgery,nerve fascicles were released,and adiposederived stromal/stem cells were administered through microinjections along the fascicles and around the adjacent tissues after external *** 36 months of followup,patients noticed gradual signs of sensory and in consequence functional *** adverse effects were *** nerve release with adipose-derived stromal/stem cells support is a promising method in patients who need secondary nerve release after nerve *** method can constitute an alternative procedure in patients experiencing recovery failure and allow improvement in cases of limited nerve *** study protocol was approved by the Institutional Review Board(IRB)at the Centre of Pos

关键词： nerve release neurolysis stem cells adipose-derived stem cells scar threshold sensation pain hypersensitivity forearm

Comprehension of functional support by enculturated chimpanzees Pan troglodytes

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Current Zoology 2011年第4期57卷 429-440页

作者： anna M. YOCOM Sarah T. BOYSEN Department of Psychology The Ohio State University Columbus OH 43210 USA

Studies of causal understanding of tool relationships in captive chimpanzees have yielded disparate findings, particularly those reported by Povinelli ＆ colleagues （2000） for tool tasks by laboratory chimpanzees. The present set of experiments tested nine enculturated chimpanzees on three versions of a support task, as described by Povinelli （2000）, during which food re- wards were presented in different experimental configurations. In Experiment 1, stimulus pairs included a choice between a cloth with a reward on the upper right comer or with a second reward off the cloth, adjacent to a comer, with the second pair comprised of a cloth with food on the upper right comer, and a second cloth with the reward on the substrate, partially covered. All subjects were successful with both test conditions in Experiment 1. In a second study, the experimental choices included one of two possi- ble correct options, paired with one of three incorrect options, with the three incorrect choices all involving varying degrees of perceptual containment. All nine chimpanzees scored significantly above chance across all six conditions. In Experiment 3, four unique conditions were presented, combining one of two possible correct choices with one of two incorrect choices. Six of the subjects scored significantly above chance across the four conditions, and group performance on individual conditions was also significant. Superior performance was demonstrated by female subjects in Experiment 3, similar to sex differences in tool use previously reported for wild chimpanzees and some tool tasks in captive chimpanzees. The present results for Experiments 2 ＆ 3 were significantly differed from those reported by Povinelli et al. （2000） for laboratory-born, peer-reared chimpanzees. One contribution towards the dramatic differences between the two study populations may be the significant rearing and housing differences of the chimpanzee groups. One explanation is that under conditions of enculturat

关键词： Chimpanzees Comparative cognition Tool use Causality

Oligodendrocyte precursor cell maturation: role of adenosine receptors

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Neural Regeneration Research 2021年第9期16卷 1686-1692页

作者： Federica Cherchi anna Maria Pugliese Elisabetta Coppi Department of Neuroscience PsychologyDrug Research and Child Health-Neurofarba-Division of Pharmacology and ToxicologyUniversity of FlorenceFlorenceItaly

Oligodendrocyte-formed myelin sheaths allow fast synaptic transmission in the brain and their degeneration leads to demyelinating diseases such as multiple sclerosis. Remyelination requires the differentiation of oligodendrocyte progenitor cells into mature oligodendrocytes but, in chronic neurodegenerative disorders, remyelination fails due to adverse environment. Therefore, a strategy to prompt oligodendrocyte progenitor cell differentiation towards myelinating oligodendrocytes is required. The neuromodulator adenosine, and its receptors(A1, A(2A), A(2B) and A3 receptors: A1R, A(2A)R, A(2B)R and A3R), are crucial mediators in remyelination processes. It is known that A1Rs facilitate oligodendrocyte progenitor cell maturation and migration whereas the A3Rs initiates apoptosis in oligodendrocyte progenitor cells. Our group of research contributed to the field by demonstrating that A(2A)R and A(2B)R inhibit oligodendrocyte progenitor cell maturation by reducing voltage-dependent K^+ currents necessary for cell differentiation. The present review summarizes the possible role of adenosine receptor ligands as potential therapeutic targets in demyelinating pathologies such as multiple sclerosis.

关键词： adenosine receptors K^+channels oligodendrocyte differentiation oligodendrocyte progenitor cells remyelination

No evidence of contagious yawning in the red-footed tortoise Geochelone carbonaria

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Current Zoology 2011年第4期57卷 477-484页

作者： anna WILKINSON Natalie SEBANZ Isabella MANDL Ludwig HUBER Department of Cognitive Biology University of Vienna Althanstrasse 14 Vienna 1090 Austria Department of Biological Sciences University of Lincoln Lincoln LN2 2LG UK Donders Institute for Brain Cognition and Behavior Centre for Cognition Radboud University Nijmegen P.O. Box 9104 6500 HE Nijmegen The Netherlands

Three hypotheses have attempted to explain the phenomenon of contagious yawning. It has been hypothesized that it is a fixed action pattern for which the releasing stimulus is the observation of another yawn, that it is the result of non-conscious mimicry emerging through close links between perception and action or that it is the result of empathy, involving the ability to engage in mental state attribution. This set of experiments sought to distinguish between these hypotheses by examining contagious yawning in a species that is unlikely to show nonconscious mimicry and empathy but does respond to social stimuli： the red-footed tortoise Geochelone carbonaria. A demonstrator tortoise was conditioned to yawn when presented with a red square-shaped stimulus. Observer tortoises were exposed to three conditions： observation of conditioned yawn, non demonstration control, and stimulus only control. We measured the number of yawns for each observer animal in each condition. There was no difference between conditions. Experiment 2 therefore increased the number of conditioned yawns presented. Again, there was no significant difference between conditions. It seemed plausible that the tortoises did not view the conditioned yawn as a real yawn and therefore a final experiment was run using video recorded stimuli. The observer tortoises were presented with three conditions： real yawn, conditioned yawns and empty background. Again there was no significant difference between conditions. We therefore conclude that the red-footed tortoise does not yawn in response to observing a conspecific yawn. This suggests that contagious yawning is not the result of a fixed action pattern but may involve more complex social processes [Current Zoology 57 （4）： 477-484, 2011].

关键词： Reptile Contagious yawn Empathy Nonconscious mimicry Fixed action pattern

Physiology of gangliosides and the role of antiganglioside antibodies in human diseases

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Cellular & Molecular Immunology 2020年第4期17卷 313-322页

作者： Gianni Cutillo anna-Helena Saariaho Seppo Meri Translational Immunology Research Program and the Department of Bacteriology and Immunology University of HelsinkiHelsinkiFinland Humanitas University MilanRozzanoItaly Helsinki University Hospital Laboratory(HUSLAB) HelsinkiFinland

Gangliosides are structurally and functionally polymorphic sialic acid containing glycosphingolipids that are widely distributed in the human *** play important roles in protecting us against immune attacks,yet they can become targets for autoimmunity and act as receptors for microbes,like the influenza viruses,and toxins,such as the cholera *** expression patterns of gangliosides vary in different tissues,during different life periods,as well as in different *** against gangliosides(AGA)can target immune attack e.g.,against neuronal cells and neutralize their complement inhibitory *** are important especially in acquired demyelinating immune-mediated neuropathies,like Guillain–Barrésyndrome(GBS)and its variant,the Miller–Fisher syndrome(MFS).They can emerge in response to different microbial agents and immunological ***,they can be involved in a variety of *** addition,antibodies against GM3 were found in the sera of patients vaccinated with Pandemrix®,who developed secondary narcolepsy,strongly supporting the autoimmune etiology of the disease.

关键词： ganglioside Guillain-Barre syndrome complement narcolepsy sialic acid

Transformation of the TiNi Alloy Microstructure and the Mechanical Properties Caused by Repeated B2-B190' Martensitic Transformations

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Acta Metallurgica Sinica(English Letters) 2015年第10期28卷 1230-1237页

作者： anna Churakova Dmitry Gunderov Alexander Lukyanov Niklas Nollmann Institute of Molecule and Crystal Physics RAS Ufa State Aviation Technical University Institute of Materials Physics University of Münster

The influences of thermal cycling treatment in the temperature range of B2-B19 martensitic transformations（-150 to 150 °C） on the Ti Ni alloy structure and properties were studied. Different states named the initial coarse-grained（CG） state, the ultrafine-grained（UFG） state after ECAP（with a grain size of 200 nm）, the state after ECAP and cold upsetting by 30% were considered. The results show that the microhardness and the strength increase in all the three *** to the XRD analysis, a more significant increment in the dislocation density, resulting from thermal cycling, is observed in the UFG alloy than in the CG alloy.

关键词： Thermal cycling TiNi alloy Equal-channel angular pressing Martensitic transformation

Seasonal comparison of moss bag technique against vertical snow samples for monitoring atmospheric pollution

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Journal of Environmental Sciences 2016年第3期28卷 128-137页

作者： Hanna Salo anna-Kaisa Berisha Joni M?kinen Department of Geography and Geology University of Turku Centre for Research of Lifelong Learning and Education(CELE) University of Turku

This is the first study seasonally applying Sphagnum papillosum moss bags and vertical snow samples for monitoring atmospheric *** bags,exposed in January,were collected together with snow samples by early March 2012 near the Harjavalta Industrial Park in southwest ***,chemical,scanning electron microscopy-energy dispersive X-ray spectroscopy（SEM-EDX）,K-means clustering,and Tomlinson pollution load index（PLI）data showed parallel spatial trends of pollution dispersal for both *** strengthen previous findings that concentrate and slag handling activities were important（dust）emission sources while the impact from Cu–Ni smelter＇s pipe remained secondary at closer *** significant correlations existed between the variables of snow and moss *** a summary,both methods work well for sampling and are efficient pollutant *** bags can be used also in winter conditions and they provide more homogeneous and better controlled sampling method than snow samples.

关键词： Biomonitoring Industrial pollution Heavy metal Magnetic susceptibility Scanning electron microscopy-energy dispersive X-ray spectroscopy