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Deterministic processes drive turnover-dominated beta diversity of breeding birds along the central Himalayan elevation gradient

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Avian Research 2024年第2期15卷 163-171页

作者： Zhifeng Ding Jianchao Liang Le Yang Cong Wei huijian hu Xingfeng Si Guangdong Key Laboratory of Animal Conservation and Resource Utilization Institute of ZoologyGuangdong Academy of SciencesGuangzhouGuangdong510260China Tibet Plateau Institute of Biology Lhasa850001China Zhejiang Zhoushan Island Ecosystem Observation and Research Station Institute of Eco-ChongmingZhejiang Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai200241China

Beta diversity,the variation of community composition among sites,bridges alpha and gamma diversity and can reveal the mechanisms of community assembly through applying distance-decay models and/or partitioning beta diversity into turnover and nestedness components from functional and phylogenetic perspectives.Mountains as the most natural experiment system provide good opportunities for exploring beta diversity patterns and the underlying ecological processes.Here,we simultaneously consider distance-decay models and multiple di-mensions of beta diversity to examine spatial variations of bird communities,and to evaluate the relative importance of niche-based and neutral community assembly mechanisms along a 3600-m elevational gradient in the central Himalayas,China.Our results showed that species turnover dominates taxonomic,functional,and phylogenetic beta diversity.We observed strongest evidence of spatial distance decays in taxonomic similarities of birds,followed by its phylogenetic and functional analogues.Turnover component was highest in taxonomic beta diversity,while nestedness component was highest in functional beta diversity.Further,all correlations of assemblage similarity with climatic distance were higher than that with spatial distances.Standardized values of overall taxonomic,functional,and phylogenetic beta diversity and their turnover components increase with increasing elevational distance,while the standardized values of taxonomic and phylogenetic nestedness decreased with increasing elevational distance.Our results highlighted the niche-based deterministic processes in shaping elevational bird diversity patterns that were determined by the relative roles of decreasing trend of environmental filtering and increasing trend of limiting similarity along elevation distances.

关键词： Beta diversity Bird Community assembly Functional trait Himalaya Nestedenss Phylogenetic distance Turnover

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SIRT1 activation synergizes with FXR agonism in hepatoprotection via governing nucleocytoplasmic shuttling and degradation of FXR

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Acta Pharmaceutica Sinica B 2023年第2期13卷 559-576页

作者： Shuang Cui huijian hu An Chen Ming Cui Xiaojie Pan Pengfei Zhang Guangji Wang Hong Wang Haiping Hao State Key Laboratory of Natural Medicines Key Laboratory of Drug Metabolism&PharmacokineticsChina Pharmaceutical UniversityNanjing 210009China

Farnesoid X receptor(FXR)is widely accepted as a promising target for various liver diseases;however,panels of ligands in drug development show limited clinical benefits,without a clear mechanism.Here,we reveal that acetylation initiates and orchestrates FXR nucleocytoplasmic shuttling and then enhances degradation by the cytosolic E3 ligase CHIP under conditions of liver injury,which represents the major culprit that limits the clinical benefits of FXR agonists against liver diseases.Upon inflammatory and apoptotic stimulation,enhanced FXR acetylation at K217,closed to the nuclear location signal,blocks its recognition by importin KPNA3,thereby preventing its nuclear import.Concomitantly,reduced phosphorylation at T442 within the nuclear export signals promotes its recognition by exportin CRM1,and thereby facilitating FXR export to the cytosol.Acetylation governs nucleocytoplasmic shuttling of FXR,resulting in enhanced cytosolic retention of FXR that is amenable to degradation by CHIP.SIRT1 activators reduce FXR acetylation and prevent its cytosolic degradation.More importantly,SIRT1 activators synergize with FXR agonists in combating acute and chronic liver injuries.In conclusion,these findings innovate a promising strategy to develop therapeutics against liver diseases by combining SIRT1 activators and FXR agonists.

关键词： FXR Nuclear receptor Acetylation Phosphorylation Nucleocytoplasmic shuttling Degradation Nonalcoholic steatohepatitis Combinatorial drugs

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Bird diversity and the conservation value of a new Ramsar site:Guangdong Haifeng Wetlands, China

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Integrative Zoology 2011年第3期6卷 266-278页

作者： Junhua hu Zhigang JIANG Chunlan ZHANG Feng XIAO huijian hu Chengdu Institute of Biology Chinese Academy of SciencesChengduChina Institute of Zoology Chinese Academy of SciencesBeijingChina South China Institute of Endangered Animals GuangzhouChina

Wetlands are critical habitats for birds.However,wetlands are being degraded at an accelerating rate due to global human activity,and a disproportionate fraction of wetland-dependent bird species are in decline.We evaluated the conservation value of a new Ramsar site,Guangdong Haifeng Wetlands,China,for birds,by comparing bird communities(using line transect data)in 3 different districts:Gongping,Dongguan Lian’anwei and Dahu.We recorded 139 species of birds,including 26 species that are protected at a national level.Dahu had the highest species richness and diversity,whereas Dongguan Lian’anwei had the highest abundance of birds and the lowest species diversity.Finally,Gongping had both the lowest species richness and the lowest abundance.The ende-mism of constituent species differed among districts,and the bird communities were complementary.There were significant seasonal differences in the species richness and the number of individuals.Spring had the highest species richness and diversity.The present study identifies the high conservation value of Haifeng Wetlands for both waterbirds and terrestrial birds.Our findings suggest that conservation efforts in Haifeng Wetlands and other wetlands should focus not only on wintering migratory birds,but also on resident birds.To accomplish effective conservation,we should consider the reserve and surrounding wetlands as a whole,incorporating ecological research,education and local economic development.

关键词： assemblage conservation Important Birds Area seasonal variation

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Bird guild loss and its determinants on subtropical land-bridge islands, China

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Chinese Birds 2015年第2期6卷 99-106页

作者： Zhifeng Ding Kenneth James Feeley huijian hu Ping Ding The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education College of Life Sciences Zhejiang UniversityZijin’gang Campus Guangdong Entomological Institute & South China Institute of Endangered Animals Department of Biological Sciences Florida International University Center for Tropical Plant Conservation Fairchild Tropical Botanic Garden

Background: The guild concept is useful for understanding the community structure in a land-bridge island system,but most fragmentation studies have focused only on the importance of island area and isolation, other island attributes such as perimeter-area ratio(PAR) were overlooked or understudied.Methods: We have adopted a guild approach to investigate the impacts of island attributes on bird guild richness on a set of 41 recently isolated land-bridge islands in the Thousand Island Lake(TIL), China.Results: We found insectivores had the largest number of species(34 species), fol owed by understory foraging guilds(28 species), omnivores(27 species) and canopy guilds(25 species). Furthermore, our data showed that migrants and residents responded equal y to island area, insectivores and understory guilds were sensitive to island area but omnivores and canopy guilds were not very sensitive. Most guild richness was determined by island area, except for omnivores and canopy guilds.Conclusions: Although PAR or habitat diversity found to be important for bird species richness, our results highlight the importance of island area in maintaining bird diversity in fragmented island systems.

关键词： Bird guilds Island area Land-bridge islands PAR Thousand Island Lake z values

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Attracted by the same sex, or repelled by the opposite sex? -Sexual segregation in Pere David's deer

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Chinese Science Bulletin 2000年第6期45卷 485-491页

作者： Zhigang Jiang Bingwan Liu Yan Zeng Gengxin Han huijian hu Institute of Zoology Chinese Academy of Sciences Beijing 100080 China

Sexual segregation behavior has attracted deep interest of zoologists in recent years. People have put forward many hypotheses to explain the phenomenon. We recommended two indices for measuring the intensity of aggregation and sexual segregation in animals, and applied those measurements to the study of aggregation and sexual segregation in free-ranging Pere David’s deer. We quantified the aggregation and segregation behavior with those methods and compared the intensities of sexual segregation in different seasons with statistic means. At the same time, the Nutritional Strategy Hypothesis, the Social-factor Hypothesis and Reproductive Strategy Hypothesis were tested in the study. We discovered that aggregation in free ranging Pere David’s deer was high in winter but low in summer. Sexual segregation in free ranging Pere Danid’s deer is caused by the reproductive strategy of different sexes, the highest degree of sexual segregation was found in the breeding season not the non-breeding season in the

关键词： milu index of aggregation intensity index of sexual segregation.

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南岭哺乳类和鸟类物种丰富度空间分布格局及其影响因子

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生物多样性 2024年第1期32卷 49-59页

作者：王丽媛胡慧建姜杰胡一鸣广东省科学院动物研究所广东省动物保护与资源利用重点实验室广东省野生动物保护与利用公共实验室广州510260 中山大学生态学院广东深圳518107 广东省林业调查规划院广州510520

作为华南地区的最大山脉和重要自然地理界线,南岭是物种丰富度研究的热点区域之一。但是已有的物种丰富度相关研究集中在局部区域和单个生物类群,缺乏对于整个南岭区域哺乳类和鸟类物种丰富度空间分布格局及其影响因子的研究。本研究利... 详细信息

作为华南地区的最大山脉和重要自然地理界线,南岭是物种丰富度研究的热点区域之一。但是已有的物种丰富度相关研究集中在局部区域和单个生物类群,缺乏对于整个南岭区域哺乳类和鸟类物种丰富度空间分布格局及其影响因子的研究。本研究利用南岭区域123种哺乳类和524种鸟类的地理分布数据,构建了整个南岭山脉的哺乳类和鸟类的物种丰富度空间分布格局。此外,我们利用路径分析和空间误差模型,探讨多种环境因子(气候、生产力、人类活动、生境异质性和海拔)对南岭哺乳类和鸟类物种丰富度空间分布格局的影响。南岭地区哺乳类和鸟类物种丰富度空间分布格局差异较大:哺乳类物种丰富度热点区域在南岭地区的西南部山地,丰富度空间分布格局总体自西向东递减;鸟类物种丰富度热点区域在南岭地区的东南部低地,丰富度空间分布格局总体自东南向西北递减。路径分析和空间误差模型显示,温度相关因子对于南岭哺乳类和鸟类物种丰富度空间分布格局影响最大。在温度相关的两个因子中,年均温与哺乳类物种丰富度呈负相关,与鸟类却呈正相关;气温年较差与哺乳类呈正相关,与鸟类却呈负相关。年均温和气温年较差对哺乳类和鸟类影响的差异可能是由哺乳类和鸟类在生理适应性和行为策略上的差异所导致。

关键词：南岭哺乳类鸟类物种丰富度分布格局影响因子

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Brood sex ratio in the Yellow-bellied Prinia(Prinia flaviventris)

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Avian Research 2017年第2期8卷 76-82页

作者： Zhifeng Ding Fang Ji Qiuli huang Longwu Wang Aiwu Jiang Chunlan Zhang Yongjun Feng Yuan Tian huijian hu Wei Liang Guangdong Key Laboratory of Animal Conservation and Resource Utilization Guangdong Public Laboratory of Wild Animal Conservation and UtilizationGuangdong Institute of Applied Biological ResourcesGuangzhou 510260China Ministry of Education Key Laboratory for Tropical Plant and Animal Ecology College of Life SciencesHainan Normal UniversityHaikou 571158China School of Life Sciences Guizhou Normal UniversityGuiyang 550001China College of Forestry Guangxi UniversityNanning 530004China

Background:The adjustment of sex ratios in birds can occur at the egg and nestling stages. Previous studies showed that the sex ratio was affected by environmental factors and parental condition; it may result in seasonal and ecosystem differences.Methods:In this study, the brood sex ratio of the Yellow-bellied Prinia(Prinia flaviventris) in the Nonggang area, Guangxi, southwestern China, was investigated during the breeding season from May to June in 2013 using PCR amplification from whole-genome DNA extracted from blood samples. A total of 31 nests of Yellow-bellied Prinia, including 132 brood fledglings and 31 pairs, were sampled.Results:The results showed that the brood sex ratio of the Yellow-bellied Prinia was 1:1, and sex ratios of different nests were evenly distributed within the study area. No significant relationship was found between parental quality and nest characteristics with the brood sex ratio.Conclusions:The present study indicated that no brood sex ratio bias in the Yellow-bellied Prinia highlighted the complexity of sex ratio adjustment in birds. In spite of our negative results, the lack of an association between brood sex ratio and parental quality and environmental factors in the Yellow-bellied Prinia provides valuable information on the adjustment of sex ratios in birds.

关键词： Brood sex ratio Parental quality Yellow-bellied Prinia Prinia flaviventris Sex ratio adjustment

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江西桃红岭保护区同域分布有蹄类动物活动节律差异

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野生动物学报 2024年第2期45卷 242-250页

作者：孔凡前沈博文李笑颖周鸭仙李言阔李佳琦万雅琼詹建文刘武华胡慧建刘丙万马钲焱江西庐山国家级自然保护区管理局九江332000 东北林业大学野生动物与自然保护地学院哈尔滨150040 江西师范大学生命科学学院南昌330022 生态环境部南京环境科学研究所南京210042 江西桃红岭梅花鹿国家级自然保护区管理局九江332700 广东省科学院动物研究所广州510260

为探究同域分布的有蹄类动物活动节律及其季节性差异,2017年3月—2019年5月,利用红外相机技术在江西桃红岭梅花鹿国家级自然保护区对有蹄类动物开展野外监测。在15208个相机有效工作日中,共拍摄到梅花鹿(Cervus nippon)、野猪(Sus scro... 详细信息

为探究同域分布的有蹄类动物活动节律及其季节性差异,2017年3月—2019年5月,利用红外相机技术在江西桃红岭梅花鹿国家级自然保护区对有蹄类动物开展野外监测。在15208个相机有效工作日中,共拍摄到梅花鹿(Cervus nippon)、野猪(Sus scrofa)和小麂(Muntiacus reevesi)3种有蹄类动物,相对丰富度依次为3.90%、9.72%和39.59%。年活动格局分析表明,梅花鹿和野猪在4月相对丰富度最高,小麂在5月和7月相对丰富度最高,三者均在12月相对丰富度最低。核密度估计和重叠系数的分析结果表明:(1)在日活动节律上,梅花鹿属于夜间活动为主、晨昏活动为辅类型,野猪与小麂同属于以晨昏活动为主、昼间活动为辅类型。(2)梅花鹿日活动节律存在明显的季节性变化,春季与夏季的重叠系数最高(Δ=0.83)。野猪与小麂日活动节律无明显的季节性变化。(3)不同物种日活动节律的重叠系数存在差异。野猪与小麂的日活动模式高度重叠,但与梅花鹿的活动高峰基本错开。研究揭示了3种有蹄类动物的活动节律及其季节性差异,为深入开展同域分布有蹄类物种的共存机制奠定了基础。

关键词：红外相机技术桃红岭保护区有蹄类活动节律季节性差异

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Mo_(2)C/Cu共负载TiO_(2)光催化CO_(2)还原性能

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洁净煤技术 2023年第5期29卷 56-67页

作者：李扬蔚慧健靳立军杨赫李德康胡浩权大连理工大学化工学院煤化工研究设计所辽宁大连116024

光能驱动CO_(2)还原技术有望减少CO_(2)排放并同时提供高价值化学燃料,缓解能源转型带来的压力。发展高活性光催化剂是实现该技术应用的关键,负载贵金属是提高其光催化效率的有效途径,但由于贵金属成本昂贵、储量稀少等原因,限制了其大... 详细信息

光能驱动CO_(2)还原技术有望减少CO_(2)排放并同时提供高价值化学燃料,缓解能源转型带来的压力。发展高活性光催化剂是实现该技术应用的关键,负载贵金属是提高其光催化效率的有效途径,但由于贵金属成本昂贵、储量稀少等原因,限制了其大规模使用。因此,发展贵金属替代品对光催化CO_(2)还原具有重要意义。Mo_(2)C是一种具有与贵金属相似的电子结构的过渡金属碳化物,采用尿素还原方式制备了Mo_(2)C和Cu共负载TiO_(2)光催化剂,结合物理化学性质分析,对其在紫外光下的光催化活性进行评价。结果表明,在TiO_(2)上负载Mo_(2)C后,在CO_(2)催化转化过程中显著促进H_(2)和CH_(4)的产生,而Mo_(2)C和Cu共沉淀可抑制H_(2)产生并促进CO_(2)进一步转化为CH_(4);光照4 h后,其CH_(4)累计产量达76.1μmol/g,为纯TiO_(2)的5.6倍。Cu沉积可促进CO_(2)吸附并抑制水蒸气吸附,从而减少H_(2)生成。Mo_(2)C和Cu的共沉积可有效减小TiO_(2)带隙宽度、抑制光生电子与空穴对的复合并促进光生电荷在催化剂表面的分离与转移,从而提高其光催化反应的活性。

关键词：光催化还原二氧化碳氧化钛类贵金属铜

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TBM滚刀贯入度对破岩效能的影响规律研究

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铁道科学与工程学报 2023年第12期20卷 4755-4768页

作者：冀国栋付柏毅章慧健耿麒王立川王灿林胡恒千中铁十八局集团有限公司天津300222 天津大学建筑工程学院天津300072 西南交通大学土木工程学院四川成都610031 长安大学工程机械学院陕西西安710061 中铁十八局集团市政工程有限公司天津300350 中铁十八局集团隧道工程有限公司重庆400700

合理设置TBM贯入度参数对于特定地质条件下的掘进效率至关重要。为研究TBM盘型滚刀在不同贯入度下的破岩效果,采用自主研发的滚刀破岩缩尺试验平台,在不同边界条件下对花岗岩开展盘型滚刀线性切割试验,通过使用FEM(finite element meth... 详细信息

合理设置TBM贯入度参数对于特定地质条件下的掘进效率至关重要。为研究TBM盘型滚刀在不同贯入度下的破岩效果,采用自主研发的滚刀破岩缩尺试验平台,在不同边界条件下对花岗岩开展盘型滚刀线性切割试验,通过使用FEM(finite element method)和SPH(smooth particle hydrodynamics)相耦合的数值模拟方法重现相关试验以验证模型的合理性,并在此基础上建立原尺双滚刀回旋破岩三维数值模型,研究TBM盘型滚刀不同贯入度下对花岗岩的破岩效果。研究结果表明:有侧限条件下滚刀受力和岩碴体积往往更大,且相邻贯入度之间的法向力和岩碴体积增长幅度随着贯入度的增大而减小,但无侧限条件下的破岩效率更高;滚刀破岩过程是阶跃性的,岩碴的产生主要集中在滚刀荷载跌落阶段,无论刀侧是否存在限制,刀下岩石均被碾压至极细的粉末,刀侧岩石崩出,且岩碴的大小与滚刀荷载跌落幅度正相关;刀下岩石破坏区域近似呈“V”形,随着贯入度的增大,滚刀间的“V”形破坏区域持续向安装半径内侧倾斜;滚刀破岩效率随着贯入度的增大先提高后减小,针对试验岩样,最佳贯入度为2~4mm;本研究所采用滚刀破岩缩尺试验与FEM-SPH数值模拟相结合的方法可以很好地重现花岗岩破裂过程,且两者切削力相对误差均在10%以内,可以为后续TBM滚刀破岩研究提供一定参考。

关键词： TBM滚刀滚刀破岩实验数值模拟贯入度比能

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