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广西崇左更新世长臂猿化石新材料（英文）

古脊椎动物学报 2018年第3期56卷 248-263页

作者：张颖奇金昌柱王元 alejandra ortiz 何锴 Terry HARRISON 中国科学院古脊椎动物与古人类研究所中国科学院脊椎动物演化与人类起源重点实验室北京100044 中国科学院生物演化与环境卓越创新中心北京100044 现代古生物学和地层学国家重点实验室中国科学院南京地质古生物研究所南京210008 美国亚利桑那州立大学人类演化与社会变化学院人类起源研究所坦佩AZ85287 中国科学院昆明动物研究所昆明650223 日本京都大学博物馆京都606-8417 美国纽约大学人类学系人类起源研究中心纽约NY10003

近年,在对广西崇左地区第四纪洞穴堆积调查的过程中,从年代贯穿更新世的8个地点采集到了33颗长臂猿游离牙齿化石。记述了这些新发现的长臂化石,并初步确定了其分类位置。形态和测量的对比表明,这些牙齿不超过现生长臂猿种内变异的范围,... 详细信息

近年,在对广西崇左地区第四纪洞穴堆积调查的过程中,从年代贯穿更新世的8个地点采集到了33颗长臂猿游离牙齿化石。记述了这些新发现的长臂化石,并初步确定了其分类位置。形态和测量的对比表明,这些牙齿不超过现生长臂猿种内变异的范围,且都可以归入一个种内。它们与冠长臂猿属(Nomascus)共有的特征组合表明,这些化石可以归入该属。这些特征包括:上臼齿相对宽,舌侧齿带及唇侧齿带痕迹保留率高;M3长度几乎与M1相等;下臼齿狭窄,并保留唇侧齿带退化痕迹。崇左地区的化石长臂猿的臼齿平均比冠长臂猿属中现生种类稍显大。但是崇左地区的游离牙齿化石材料提供的证据并不足以支持将其归入该属中的某一具体种类。与中国南方更新世其他同时代的大型猿类猩猩(Pongo)和巨猿(Gigantopithecus)不同,长臂猿的牙齿大小并没有随时间发生变化。尽管冠长臂猿属在现今的崇左地区并没有分布,但是在历史时期该属曾经广泛分布于中国南方地区。

关键词：广西崇左更新世冠长臂猿属分类学游离牙齿演化牙齿大小

On Rigid 2-Step Nilpotent Lie Algebras

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Algebra Colloquium 2018年第2期25卷 349-360页

作者： Maria alejandra Alvarez Departamento de Matematicas Facultad de Ciencias Basicas Universidad de Antofagasta Casilla 170 Antofagasta Chile

In this note we consider 2-step nilpotent Lie algebras and give a criterion for the rigidity of this class in the variety N2n of 2-step nilpotent Lie algebras of dimension n. We apply this criterion to prove that ever... 详细信息

关键词： nilpotent Lie algebras variety of Lie algebras deformations cohomology,nilradicals

Changes in niche differentiation and environmental filtering over a hydric stress gradient

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Journal of Plant Ecology 2020年第2期13卷 185-194页

作者： alejandra Martínez-Blancas Carlos Martorell Departamento de Ecología y Recursos Naturales Facultad de CienciasUniversidad Nacional Autónoma de MéxicoCoyoacán04510 Ciudad de MéxicoMexico Posgrado en Ciencias Biológicas Universidad Nacional Autónoma de MéxicoAv.Ciudad Universitaria 3000C.P.04510CoyoacánCiudad de MéxicoMexico

Aims Diversity in communities is determined by species’ability to coexist with each other and to overcome environmental stress that may act as an environmental *** differentiation(ND)results in stronger intra-than interspecific competition and promotes *** stress affects interactions,the strength of ND may change along stress gradients.A greater diversity of plant growth forms has been observed in stressful habitats,such as deserts and alpine regions,suggesting greater ND when stress is *** tested the hypothesis that niche differences and environmental filters become stronger with *** In a semiarid grassland in southern Mexico,we sowed six annual species in the field along a hydric stress *** were grown alone(without interactions),with conspecific neighbors(intraspecific interactions)or with heterospecific neighbors(interspecific interactions).We analyzed how the ratio of intra-to interspecific competition changed along the gradient to assess how water availability determines the strength of *** also determined if hydric stress represented an environmental *** Findings We observed stronger intra-than interspecific competition,especially where hydric stress was ***,we found ND in at least some portion of the gradient for all but one *** species were hindered by stress,but others were favored by it perhaps because it eliminates soil *** strong ND was slightly more frequent with stress,our species sample was small and there were exceptions to the general pattern,so further research is needed to establish if this is a widespread phenomenon in nature.

关键词： hydrological niche species interactions environmental constraints species coexistence stabilizing mechanisms equalizing mechanisms

Oligo-carrageenan kappa increases C, N and S assimilation, auxin and gibberellin contents, and growth in Pinus radiata trees

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Journal of Forestry Research 2015年第3期26卷 635-640页

作者： Silvia Saucedo Rodrigo A. Contreras alejandra Moenne University of Santiago of Chile Santiago Chile Facultad de Ciencias Agrarias Universidad Te'cnica Estatal de Quevedo 63 Quevedo Ecuador

Oligo-carrageenans （OCs） obtained from pure carrageenans extracted from marine red algae stimulate growth by enhancing photosynthesis and basal metabolism in tobacco plants and Eucalyptus trees. In addition, OCs stimulate secondary metabolism, increasing the level of metabolites involved in defense against pathogens. In this work, we analyzed the effect of OC kappa on the increase in height, in activities of basal metabolism enzymes in- volved in carbon, nitrogen and sulphur assimilation, ribu- lose 1,5 biphosphate carboxylase/oxygenase （rubisco）, glutamate dehydrogenase （GDH） and O-acetylserine thiol- lyase （OASTL）, and in the level of growth-promoting hormones, the auxin indole acetic acid （IAA） and the gibberellin GA3, in pine （Pinus radiata） trees treated with OC kappa at concentrations of 1 and 5 mg mL-1 and cultivated for 9 months without additional treatment. Pines treated with OC kappa at 1 mg mL-1 showed a similar increase in height but displayed a higher increased in total chlorophyll, activities of rubisco, GDH and OASTL and level of IAA and GA3 than those treated with OC kappa at 5 mg mL-1. Thus, OC kappa stimulates growth and basal metabolism and increases the level of growth-promoting hormones in pine trees, mainly at 1 mg mL-1.

关键词： Auxin Basal metabolism C, N and Sassimilation Gibberellin Oligo-carrageenan kappaPinus radiata

Social Isolation in Male Rats During Adolescence Inhibits the Wnt/β-Catenin Pathway in the Prefrontal Cortex and Enhances Anxiety and Cocaine-Induced Plasticity in Adulthood

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Neuroscience Bulletin 2020年第6期36卷 611-624页

作者： Santiago Cuesta Alejandrina Funes alejandra M.Pacchioni Area Toxicologia Departamento de Ciencias de los Alimentos y del MedioambienteFacultad de Ciencias Bioquimicas y FarmaceuticasUniversidad Nacional de RosarioSuipacha 5312000 RosarioSanta FeArgentina Consejo Nacional de Investigaciones Cientificas y Tecnicas RosarioArgentina Present Address:Department of Microbiology University of Texas Southwestern Medical CenterDallasTX 75390USA

In adult animals,it is well established that stress has a proactive effect on psychostimulant ***,whether only a short period of stress during adolescence can also affect cocaine responses later in life and what mechanisms are involved are ***,we showed that 5 days of social isolation during rat adolescence had a long-term impact on anxiety-like behaviors,cocaine-induced conditioned place preference,and the expression of sensitization during *** the molecular level,social isolation decreased the activity of the Wnt/β-catenin pathway in the prefrontal cortex(PFC).Furthermore,after the expression of cocaine sensitization,isolated rats showed an increase in this pathway in the nucleus ***,these findings suggest that,adolescent social isolation by altering the Wnt/β-catenin pathway in the developing PFC might increase the cocaine responses during adulthood,introducing this pathway as a novel neuroadaptation in the cortical-accumbens connection that may mediate a stress-induced increase in vulnerability to drugs.

关键词： Social isolation Adolescence Cocaine vulnerability Wnt/(i-catenin pathway

In the beginning,there was only bare regolith-then some plants arrived and changed the regolith

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Journal of Plant Ecology 2020年第5期13卷 511-516页

作者： Jun Zhou alejandra Zúñiga-Feest Hans Lambers Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Laboratorio de Biología Vegetal Instituto de Ciencias Ambientales y EvolutivasFacultad de CienciasUniversidad Austral de ChileValdiviaChile School of Biological Sciences The University of Western Australia35 Stirling HighwayCrawley(Perth)WA 6009Australia College of Resources and Environmental Sciences National Academy of Agriculture Green DevelopmentKey Laboratory of Plant-Soil InteractionsMinistry of EducationChina Agricultural University100193 BeijingChina

Pedogenesis along chronosequences has received attention from soil scientists for decades,following the pioneering work of Walker and Syers(1976),who showed a general pattern of the availability of nitrogen(N)and phosphorus(P)subsequently confirmed for a range of chronosequences(Huggett 1998;Turner and Condron 2013;Vitousek and Farrington 1997).Much more recently,changes of plant nutrient-acquisition strategies with soil development have drawn attention,first with a conceptual model(Lambers et al.2008),which was subsequently confirmed with solid experimental data collected along the Jurien Bay chronosequence in south-western Australia(Zemunik et al.2015).The original conceptual model has since been amended,to explain why presumably less-effective mycorrhizal P-acquisition strategies coexist with more-effective strategies based on the release carboxylates(organic anions)(Lambers et al.2018).Mycorrhizas may not be effective at acquiring P from severely P-impoverished soils,but they do boost the defence against pathogens,which strongly affect the growth of non-mycorrhizal carboxylate-releasing Proteaceae(Albornoz et al.2017;Lalibertéet al.2015).What has received little or no attention is the P-acquisition strategies of species that are the first to colonize the bare regolith of the earliest stage of chronosequences(Figs 1 and 2).When the soil P availability is relatively high such as along the Jurien Bay chronosequence(Turner et al.2018),there is little point searching for specialized strategies,but along many chronosequences,*** the case(Egli et al.2012;Richardson et al.2004;Zhou et al.2019).

关键词： soil fir Richardson

Microbial symphony orchestrated by mucosal IgA

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Cellular & Molecular Immunology 2022年第4期19卷 456-457页

作者： alejandra Reyes-Ruiz Jordan D.Dimitrov Centre de Recherche des Cordeliers INSERMCNRSSorbonne UniversitéUniversitéde Paris75006ParisFrance

The ability of an organism to handle the beauty and cruelty of existence is largely due to a complex network of molecular and cellular interactions and processes named the immune *** components of this network are antibodies(Abs)that have key roles in immune defense and *** biological functions of Abs include neutralizing pathogens by blocking functionally important molecules and/or to eliciting lethal effector functions by bridging the recognition of pathogens with binding to different innate immune receptors.

关键词： bridging neutral network

Biological processes and signal transduction pathwaysregulated by the protein methyltransferase SETD7 and theirsignificance in cancer

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Signal Transduction and Targeted Therapy 2018年第1期3卷 137-150页

作者： Ines de Albuquerque Almeida Batista Luisa alejandra Helguero Institute for Biomedicine(iBiMED) Department of Medical SciencesUniversity of AveiroAveiroPortugal

Protein methyltransferases have been shown to methylate histone and non-histone proteins,leading to regulation of several biological processes that control cell *** the past few years,the histone-lysine N-methyltransferase SETD7(SETD7;also known as SET7/9,KIAA1717,KMT7,SET7,SET9)has emerged as an important regulator of at least 30 non-histone proteins and a potential target for the treatment of several human *** review discusses current knowledge of the structure and subcellular localization of SETD7,as well as its function as a histone and non-histone *** work also underlines the putative contribution of SETD7 to the regulation of gene expression,control of cell proliferation,differentiation and endoplasmic reticulum stress,which indicate that SETD7 is a candidate for novel targeted therapies with the aim of either stimulating or inhibiting its activity,depending on the cell signaling context.

关键词： homeostasis stimulating signal

Molecular phylogeny of the genus Sticta (lichenized Ascomycota: Lobariaceae) in Colombia

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Fungal Diversity 2014年第1期64卷 205-231页

作者： Bibiana Moncada Robert Lücking alejandra Suárez Licenciatura en Biología Universidad Distrital Francisco Joséde CaldasCra.4 No.26B-54Torre de LaboratoriosHerbarioBogotáColombia Department of Botany The Field Museum1400 South Lake Shore DriveChicagoIL 60605USA

We present a molecular phylogenetic study of the lichen genus Sticta focusing on Colombia,using the ITS fungal barcoding gene for a total of 370 ingroup OTUs,with 322 newly generated *** topology resulting from a maximum likelihood approach does not support current species concepts in Sticta,which use a morphological concept,but in contrast shows that similar morphodemes evolved multiple times independently within the *** a consequence,currently applied names such as *** and *** comprise numerous(up to more than 20)unrelated species-level lineages,which can be distinguished also phenotypically using previously unrecognized characters such as lobe configuration,lobe surface structure,tomentum type,and anatomy of the basal membrane of the *** conclude that the genus Sticta contains about four to five times the number of species currently *** Colombia alone,approximately 150 species of Sticta are present.

关键词： Lichen-forming fungi Morphological species concept Parallel evolution