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121.
北京雾灵山自然保护区冬春季地面活动鸟兽红外相机初步调查 总被引:4,自引:0,他引:4
为了解北京雾灵山自然保护区野生动物资源现状,于2014年11月至2015年4月,在保护区内放置30台红外相机开展调查。结果共记录鸟类5目14科27种,兽类4目8科10种,其中勺鸡(Pucrasia macrolopha)、红角鸮(Otus sunia)、纵纹腹小鸮(Athene noctua)和中华斑羚(Naemorhedus griseus)为国家Ⅱ级重点保护野生动物。鸟类物种数月变化剧烈。相对丰富度最高的6种动物为狍(Capreolus pygargus)(60.19)、红嘴蓝鹊(Urocissa erythrorhyncha)(34.14)、星鸦(Nucifraga caryocatactes)(27.78)、岩松鼠(Sciurotamias davidianus)(23.34)、松鸦(Garrulus glandarius)(23.34)、中华斑羚(21.99)。对狍、岩松鼠、中华斑羚进行日活动节律分析,狍属晨昏活动型;中华斑羚有两个活动高峰;岩松鼠的日活动高峰集中在晨间,为单峰型。本研究提供了北京雾灵山部分鸟兽资源的最新动态现状及活动节律信息,同时表明红外相机在拍摄地栖性鸟类、大中型兽类、夜行性动物方面具有优势,而对于非地栖鸟类和小型兽类,红外相机有一定局限性。本研究为应用红外相机技术开展森林野生动物多样性监测提供了经验。 相似文献
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Break the pattern: breakpoints in beta diversity of vertebrates are general across clades and suggest common historical causes
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Adrián Castro‐Insua Carola Gómez‐Rodríguez Andrés Baselga 《Global Ecology and Biogeography》2016,25(11):1279-1283
The use of correlative analyses might be insufficient to understand the processes that control biodiversity, because the variables accounting for different hypotheses (e.g. current climate, past climate change, post‐glacial dispersal limitation) are mutually correlated. We suggest here that, in order to gain insight, it could be useful to search for latitudinal thresholds that could provide information about qualitative changes in the way biodiversity varies in space. Such tipping points could inform about higher‐level processes that are not reflected in correlative analyses. We test whether similar breakpoints in latitudinal beta‐diversity patterns exist for different vertebrate groups with diverse life histories and dispersal abilities. In birds, bats and non‐volant mammals we find breakpoints similar to those of amphibians. Differences in species composition are mainly due to species replacement from the equator to the breakpoint, but are dominated by nested species losses from the breakpoint to higher latitudes. Thus, marked thresholds discriminate two world regions where different processes appear to drive biodiversity. 相似文献
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Jingyi Zhou Gangyang Wang Yinze Chen Hongxia Wang Yingqi Hua Zhengdong Cai 《Journal of cellular and molecular medicine》2019,23(8):4854-4865
In the tumour microenvironment (TME), immunogenic cell death (ICD) plays a major role in stimulating the dysfunctional antitumour immune system. Chronic exposure of damage‐associated molecular patterns (DAMPs) attracts receptors and ligands on dendritic cells (DCs) and activates immature DCs to transition to a mature phenotype, which promotes the processing of phagocytic cargo in DCs and accelerates the engulfment of antigenic components by DCs. Consequently, via antigen presentation, DCs stimulate specific T cell responses that kill more cancer cells. The induction of ICD eventually results in long‐lasting protective antitumour immunity. Through the exploration of ICD inducers, recent studies have shown that there are many novel modalities with the ability to induce immunogenic cancer cell death. In this review, we mainly discussed and summarized the emerging methods for inducing immunogenic cancer cell death. Concepts and molecular mechanisms relevant to antitumour effects of ICD are also briefly discussed. 相似文献
126.
Tripartite motif(TRIM) proteins were shown to play an important role in innate antiviral immunity. FinTRIM(ftr) is a new subset of TRIM genes that do not possess obvious orthologs in higher vertebrates. However, little is known about its function. In this study, we used bioinformatic analysis to examine the phylogenetic relationships and conserved domains of zebrafish(Danio rerio) ftr01, ftr42, and ftr58, as well as qualitative real-time PCR to examine their expression patterns in zebrafish embryonic fibroblast(ZF4) cells and zebrafish tissues. Sequence analysis showed that the three finTRIMs are highly conserved, and all contain a RING domain, B-box domain, and SPRY-PRY domain. In addition, ftr42 and ftr58 had one coiled-coil domain(CCD), whereas ftr01 had two CCDs. Tissue expression analysis revealed that the m RNA level of ftr01 was the highest in the liver, whereas those of ftr42 and ftr58 were the highest in the gill; the expression of thesefinTRIMs was clearly upregulated not in the eyes, but in the liver, spleen, kidney, gill, and brain of zebrafish following spring viremia of carp virus(SVCV) infection. Similarly, the expression of these three finTRIM genes also increased in ZF4 cells after SVCV infection. Our study revealed that ftr01, ftr42, and ftr58 may play an important role in antiviral immune responses, and these findings validate the need for more in-depth research on the finTRIM family in the future. 相似文献
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《Fungal Ecology》2019
Laboulbeniales (Ascomycota: Laboulbeniomycetes) are obligate ectoparasitic fungi of arthropods with a worldwide distribution. Their effects on host physiology and behaviour as well as their ecology have recently gained wider attention. One aspect that is virtually unknown regarding Laboulbeniales and arthropod-associated fungi in general, is how abiotic factors shape the distribution of these parasites. We used ant- and bat fly-associated Laboulbeniales to study whether climatic elements play a role in the distribution of fungal species. We collected uninfected and Laboulbeniales-infected insects belonging to three species: bat flies Nycteribia schmidlii and Penicillidia conspicua (Diptera: Nycteribiidae) and the ant Myrmica scabrinodis (Hymenoptera: Formicidae). We used climatic variables and performed statistical analyses to explain the distribution of Laboulbeniales infection. Our results show a higher likelihood of Laboulbeniales presence in habitats with low annual mean temperature and humidity, suggesting that climatic elements can considerably shape the distribution of Laboulbeniales species. 相似文献
129.
Caterina R. Giner Vanessa Balagu Anders K. Krabberd Isabel Ferrera Albert Re Esther Garcs Josep M. Gasol Ramiro Logares Ramon Massana 《Molecular ecology》2019,28(5):923-935
How much temporal recurrence is present in microbial assemblages is still an unanswered ecological question. Even though marked seasonal changes have been reported for whole microbial communities, less is known on the dynamics and seasonality of individual taxa. Here, we aim at understanding microbial recurrence at three different levels: community, taxonomic group and operational taxonomic units (OTUs). For that, we focused on a model microbial eukaryotic community populating a long‐term marine microbial observatory using 18S rRNA gene data from two organismal size fractions: the picoplankton (0.2–3 µm) and the nanoplankton (3–20 µm). We have developed an index to quantify recurrence in particular taxa. We found that community structure oscillated systematically between two main configurations corresponding to winter and summer over the 10 years studied. A few taxonomic groups such as Mamiellophyceae or MALV‐III presented clear recurrence (i.e., seasonality), whereas 13%–19% of the OTUs in both size fractions, accounting for ~40% of the relative abundance, featured recurrent dynamics. Altogether, our work links long‐term whole community dynamics with that of individual OTUs and taxonomic groups, indicating that recurrent and non‐recurrent changes characterize the dynamics of microbial assemblages. 相似文献
130.
Thioredoxins (TRXs) are distributed ubiquitously in prokaryotic and eukaryotic organisms. Plants have the most complex forms
of TRXs. The functional roles of such TRXs have been studied in abiotic stress but their roles in plant defense responses
against biotic stresses have been less well studied. Here, we identified an h-type TRX gene from pepper, CaTRXh1, and characterized its possible effect on Type II nonhost resistance, which entails localized programmed cell death in response
to nonhost pathogens. Peptide sequences of CaTRXh1 showed a high degree of similarity with TRXhs from tobacco and Arabidopsis thaliana. Southern blot analyses revealed that CaTRXh1 was present as a single copy in the pepper genome. Intriguingly, leaf infiltration by Xanthomonas axonopodis pv. glycines 8ra, eliciting a visible type II nonhost hypersensitive response (HR), and its type III secretion-system null mutant 8–13,
eliciting a type I nonhost non-HR, both induced CaTRXh1 at a level similar to that of pathogenesis-related protein 4, an HR marker gene in pepper. More surprisingly, expression
of CaTRXh1 was significantly increased when X. axonopodis pv. vesicatoria race 3 infiltrated the leaf of a pepper cultivar containing a resistance gene, but not with infiltration of a susceptible
pepper cultivar. Taken together, our study suggests that the expression of CaTRXh1 has a critical role in HR-mediated active defense responses in pepper.
GenBank accession number: EF371503. 相似文献