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Late Olenekian Radiolarians from Bedded Chert of Ashio Terrane, Northeast Japan, and Faunal Turnovers in Western Panthalassa during Early Triassic 被引量:1
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作者 NoritoshiSuzuki NatsumiAkiba 《Journal of China University of Geosciences》 SCIE CSCD 2002年第2期124-140,T001,共18页
Late Olenekian assemblages in the western Panthalassa have been recovered from bedded radiolarian chert sequences of an accretionary complex, the Ashio belt. These faunas are documented and considered in terms of radi... Late Olenekian assemblages in the western Panthalassa have been recovered from bedded radiolarian chert sequences of an accretionary complex, the Ashio belt. These faunas are documented and considered in terms of radiolarian diversity and faunal turnover during the latest Permian to Middle Triassic time. The fauna includes 30 radiolarians belonging to Spumellaria or Entactinaria, with two relicts from the Late Permian. This late Olenekian fauna is markedly different from Permian and Anisian faunas, respectively, and is herein named the Minowa fauna. Study of the literature indicates that radiolarian provinces were significantly disconnected between the western Panthalassa and eastern Tethys during late Olenekian time. Furthermore, 121 of 143 species disappeared during late Olenekian time, and in turn 118 new species appeared in the western Panthalassa around the Olenekian Anisian boundary. It is concluded that faunal turnover occurred at least three times between the latest Permian and Middle Triassic. The first turnover is the Paleozoic type radiolarian extinction at the Permian Triassic boundary, the second is the diversification of spheroidal Spumellaria and Entactinaria between early and late Olenekian time, and the third is a faunal turnover from the Minowa fauna to the true Mesozoic type radiolarian faunas that are characterized by multi segmented Nassellaria. 展开更多
关键词 RADIOLARIA Early Triassic Middle Triassic faunal turnover mass extinction Minowa radiolarian fauna.
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Calcium-fortified fresh milk ameliorates postmenopausal osteoporosis via regulation of bone metabolism and gut microbiota in ovariectomized rats 被引量:1
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作者 Qishan Wang Bin Liu +5 位作者 Xianping Li Junying Zhao Zongshen Zhang Weicang Qiao Xinyue Wei Lijun Chen 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1258-1270,共13页
The aging of the global population has made postmenopausal osteoporosis prevention essential;however,pharmacological treatments are limited.Herein,we evaluate the effect of calcium-fortified fresh milk(FM)in ameliorat... The aging of the global population has made postmenopausal osteoporosis prevention essential;however,pharmacological treatments are limited.Herein,we evaluate the effect of calcium-fortified fresh milk(FM)in ameliorating postmenopausal osteoporosis in a rat model established using bilateral ovariectomy.After 3 months of FM(containing vitamin D,and casein phosphopeptides,1000 mg Ca/100 g)or control milk(110 mg Ca/100 g milk)supplementation,bone changes were assessed using dual-energy X-ray absorptiometry,microcomputed tomography,and bone biomechanical testing.The results revealed that FM can regulate bone metabolism and gut microbiota composition,which act on bone metabolism through pathways associated with steroid hormone biosynthesis,relaxin signaling,serotonergic synapse,and unsaturated fatty acid biosynthesis.Furthermore,FM administration significantly increased bone mineral content and density in the lumbar spine and femur,as well as femoral compressive strength,while improving femoral trabecular bone parameters and microarchitecture.Mechanistically,we found that the effects may be due to increased levels of estrogen,bone formation marker osteocalcin,and procollagen typeⅠN-propeptide,and decreased expression of the bone resorption marker C-telopiptide and tartrate-resistant acid phosphatase 5b.Overall,the findings suggest that FM is a potential alternative therapeutic option for ameliorating postmenopausal osteoporosis. 展开更多
关键词 Dairy products CALCIUM Vitamin D Bone turnover markers Gut microbiota Postmenopausal osteoporosis
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Dietary xylo‑oligosaccharides and arabinoxylans improved growth efficiency by reducing gut epithelial cell turnover in broiler chickens
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作者 Carla Castro Shahram Niknafs +3 位作者 Gemma Gonzalez‑Ortiz Xinle Tan Michael R.Bedford Eugeni Roura 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1325-1335,共11页
Background One of the main roles of the intestinal mucosa is to protect against environmental hazards.Supple-mentation of xylo-oligosaccharides(XOS)is known to selectively stimulate the growth of beneficial intestinal... Background One of the main roles of the intestinal mucosa is to protect against environmental hazards.Supple-mentation of xylo-oligosaccharides(XOS)is known to selectively stimulate the growth of beneficial intestinal bacteria and improve gut health and function in chickens.XOS may have an impact on the integrity of the intestinal epithelia where cell turnover is critical to maintain the compatibility between the digestive and barrier functions.The aim of the study was to evaluate the effect of XOS and an arabinoxylan-rich fraction(AXRF)supplementation on gut func-tion and epithelial integrity in broiler chickens.Methods A total of 128 broiler chickens(Ross 308)were assigned into one of two different dietary treatments for a period of 42 d:1)control diet consisting of a corn/soybean meal-based diet;or 2)a control diet supplemented with 0.5%XOS and 1%AXRF.Each treatment was randomly distributed across 8 pens(n=8)with 8 chickens each.Feed intake and body weight were recorded weekly.On d 42,one male chicken per pen was selected based on aver-age weight and euthanized,jejunum samples were collected for proteomics analysis.Results Dietary XOS/AXRF supplementation improved feed efficiency(P<0.05)from d 1 to 42 compared to the con-trol group.Proteomic analysis was used to understand the mechanism of improved efficiency uncovering 346 dif-ferentially abundant proteins(DAP)(Padj<0.00001)in supplemented chickens compared to the non-supplemented group.In the jejunum,the DAP translated into decreased ATP production indicating lower energy expenditure by the tissue(e.g.,inhibition of glycolysis and tricarboxylic acid cycle pathways).In addition,DAP were associated with decreased epithelial cell differentiation,and migration by reducing the actin polymerization pathway.Put-ting the two main pathways together,XOS/AXRF supplementation may decrease around 19%the energy required for the maintenance of the gastrointestinal tract.Conclusions Dietary XOS/AXRF supplementation improved growth efficiency by reducing epithelial cell migration and differentiation(hence,turnover),actin polymerization,and consequently energy requirement for maintenance of the jejunum of broiler chickens. 展开更多
关键词 ACTIN ARABINOXYLANS BROILER Cell turnover Energy metabolism JEJUNUM Xylo-oligosaccharides
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Life forms affect beta-diversity patterns of larch forests in China
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作者 Wenjing Fang Qiong Cai +3 位作者 Chengjun Ji Jiangling Zhu Zhiyao Tang Jingyun Fang 《Plant Diversity》 SCIE CAS CSCD 2024年第1期49-58,共10页
Beta-diversity reflects the spatial changes in community species composition which helps to understand how communities are assembled and biodiversity is formed and maintained. Larch(Larix) forests, which are coniferou... Beta-diversity reflects the spatial changes in community species composition which helps to understand how communities are assembled and biodiversity is formed and maintained. Larch(Larix) forests, which are coniferous forests widely distributed in the mountainous and plateau areas in North and Southwest China, are critical for maintaining the environmental conditions and species diversity. Few studies of larch forests have examined the beta-diversity and its constituent components(species turnover and nestedness-resultant components). Here, we used 483 larch forest plots to determine the total betadiversity and its components in different life forms(i.e., tree, shrub, and herb) of larch forests in China and to evaluate the main drivers that underlie this beta-diversity. We found that total betadiversity of larch forests was mainly dependent on the species turnover component. In all life forms,total beta-diversity and the species turnover component increased with increasing geographic, elevational, current climatic, and paleoclimatic distances. In contrast, the nestedness-resultant component decreased across these same distances. Geographic and environmental factors explained 20%-25% of total beta-diversity, 18%-27% of species turnover component, and 4%-16% of nestedness-resultant component. Larch forest types significantly affected total beta-diversity and species turnover component. Taken together, our results indicate that life forms affect beta-diversity patterns of larch forests in China, and that beta-diversity is driven by both niche differentiation and dispersal limitation. Our findings help to greatly understand the mechanisms of community assemblies of larch forests in China. 展开更多
关键词 BETA-DIVERSITY Species turnover Nestedness-resultant Geographic distance Climatic distance Larch forest
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Deterministic processes drive turnover-dominated beta diversity of breeding birds along the central Himalayan elevation gradient
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作者 Zhifeng Ding Jianchao Liang +3 位作者 Le Yang Cong Wei Huijian Hu Xingfeng Si 《Avian Research》 SCIE CSCD 2024年第2期163-171,共9页
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 d... 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. 展开更多
关键词 Beta diversity BIRD Community assembly Functional trait HIMALAYA Nestedenss Phylogenetic distance TURNOVER
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Hydrogen evolution reaction activity enhancement from active site turnover mechanism
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作者 Jiacheng Wang Tongqing Yang +4 位作者 Xiyue Li Haiqin Zhang Yixue Zhang Yan He Hongyao Xue 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期629-638,共10页
Although heteroatom doping is an effective way to improve the catalytic activity of transition metal phosphides(TMPs),the mechanism of activity enhancement needs to be further refined.To this end,we synthesized a Co-d... Although heteroatom doping is an effective way to improve the catalytic activity of transition metal phosphides(TMPs),the mechanism of activity enhancement needs to be further refined.To this end,we synthesized a Co-doped Ni_(2)P catalyst as a research model and found that the introduction of heterogeneous Co reconstructed the charge distribution around the P site,which effectively enhanced the hydrogen evolution reaction(HER)activity of the pure Ni_(2)P.Based on in-situ Raman real-time monitoring technology,we monitored for the first time that Co doping triggered a switch of the active site(from the original Co-active site to the P-active site),which promoted the adsorption of H_(2)O to enhance the HER activity.The density functional theory(DFT)calculations indicated that the P site of Co-Ni_(2)P expressed the highest activity and the Ni site of pure Ni_(2)P expressed the highest activity,which further confirms the in-situ Raman monitoring results.The active site turnover mechanism discovered in this study will undoubtedly provide more rational and targeted ideas for future catalyst design. 展开更多
关键词 In-situ Raman observation Heteroatom doping Activesites turnover Hydrogen production
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某三级专科医院护士人格特质与离职意愿的相关性 被引量:1
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作者 刘光辉 严非 +3 位作者 程骋 归纯漪 聂雯瑾 包江波 《中国卫生资源》 CSCD 北大核心 2023年第1期127-132,共6页
目的调查上海市某三级专科医院护士离职意愿现状,探讨护士人格特质、工作支持和工作满意度与离职意愿的关系及人格特质对离职意愿的影响。方法2022年1—2月对上海市某三级专科医院的全体护士进行调查,采用自编社会人口学资料调查表、中... 目的调查上海市某三级专科医院护士离职意愿现状,探讨护士人格特质、工作支持和工作满意度与离职意愿的关系及人格特质对离职意愿的影响。方法2022年1—2月对上海市某三级专科医院的全体护士进行调查,采用自编社会人口学资料调查表、中国大五人格问卷简式版量表、工作支持量表、工作满意度量表、离职意愿量表调查。用SPSS 24.0对数据进行统计学分析,用t检验和方差分析进行单因素组间比较,采用分层逐步回归分析离职意愿的影响因素。结果共回收473份问卷。受调查护士离职意愿总分为(14.03±3.76)分;大五人格各维度得分从高到低依次为宜人性(35.72±5.71)分、严谨性(34.13±6.03)分、开放性(29.94±6.64)分、外向性(28.29±6.27)分、神经质(24.84±7.58)分;工作支持得分为(71.05±15.34)分、工作满意度得分为(30.60±6.26)分。不同年龄、职称、工作年限、夜班频次以及有无编制的护士的离职意愿得分差异有统计学意义(P<0.05)。Pearson相关分析结果显示:神经质与离职意愿呈正相关;严谨性、宜人性、外向性、工作支持、工作满意度与离职意愿呈负相关。分层逐步回归分析结果显示,宜人性能够解释护士离职意愿0.7%的变异。结论上海市某三级专科医院护士离职意愿水平较高。护士的人格特质、工作支持和工作满意度会影响护士的离职意愿,具有宜人性的个体表现出较低的离职意愿。 展开更多
关键词 护士nurse 大五人格big-five personality 离职意愿turnover intention 工作支持work support 工作满意度job satisfaction
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Association of bone turnover biomarkers with severe intracranial and extracranial artery stenosis in type 2 diabetes mellitus patients 被引量:1
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作者 Si-Cong Si Wei Yang +3 位作者 Hong-Yu Luo Yi-Xin Ma Huan Zhao Jia Liu 《World Journal of Diabetes》 SCIE 2023年第5期594-605,共12页
BACKGROUND Intracranial and extracranial artery stenosis is associated with cerebral infarction.Vascular calcification and atherosclerosis are the main causes of stenosis and major risk factors for cardiovascular and ... BACKGROUND Intracranial and extracranial artery stenosis is associated with cerebral infarction.Vascular calcification and atherosclerosis are the main causes of stenosis and major risk factors for cardiovascular and cerebrovascular events in patients with type 2 diabetes mellitus(T2DM).Bone turnover biomarkers(BTMs)are associated with vascular calcification,atherosclerosis,glucose,and lipid metabolism.AIM To investigate the association of circulating BTM levels with severe intracranial and extracranial artery stenosis in patients with T2DM.METHODS For this cross-sectional study including 257 T2DM patients,levels of the BTMs serum osteocalcin(OC),C-terminal cross-linked telopeptide of type I collagen(CTX),and procollagen type I N-peptide were measured by electrical chemiluminescent immunoassay,and artery stenosis was assessed by color Doppler and transcranial Doppler.Patients were grouped according to the existence and location(intracranial vs.extracranial)of artery stenosis.Correlations between BTM levels,previous stroke,stenosis location,and glucose and lipid metabolism were analyzed.RESULTS T2DM patients with severe artery stenosis had a higher frequency of previous stroke and levels of all three tested BTMs(all P<0.05)than patients without.Some differences in OC and CTX levels were observed according to the location of artery stenosis.Significant associations were also observed between BTM levels and some glucose and lipid homeostasis parameters.On multivariate logistic regression analysis,all BTMs were significant predictors of artery stenosis in T2DM patients with and without adjustment for confounding factors(all P<0.001),and receiver operating characteristic curve analysis demonstrated the ability of BTM levels to predict artery stenosis in T2DM patients.CONCLUSION BTM levels were found to be independent risk factors for severe intracranial and extracranial artery stenosis and were differentially associated with glucose and lipid metabolism in patients with T2DM.Therefore,BTMs may be promising biomarkers and potential therapeutic targets for artery stenosis. 展开更多
关键词 Bone turnover biomarkers Type 2 diabetes mellitus OSTEOCALCIN C-terminal cross-linked telopeptide of type I collagen Procollagen type I N-peptide Intracranial and extracranial artery stenosis
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Shared-role of vegetation types,elevation and soil affecting plant diversity in an old-tropical mountain hotspot
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作者 Priscilla P.LOIOLA Leonor Patrícia Cerdeira MORELLATO +4 位作者 Maria Gabriela Gutierrez CAMARGO Vitor A.KAMIMURA Jacqueline S.MATTOS Annia Susin STREHER Soizig LE STRADIC 《Journal of Mountain Science》 SCIE CSCD 2023年第7期1842-1853,共12页
Despite the exceptional species richness and endemism,the environmental drivers of plant diversity along old tropical mountains remain underexplored.The respective importance of vegetation types,elevation,slope,and so... Despite the exceptional species richness and endemism,the environmental drivers of plant diversity along old tropical mountains remain underexplored.The respective importance of vegetation types,elevation,slope,and soil to drive diversity across life-forms is poorly addressed.Here,we tested whether environmental variables drove local and regional plant diversity along an old tropical mountain according to the three main life-forms:graminoids,herbaceous and woody species.We sampled all Angiosperm species on 180 plots across five elevations,at the tropical old-mountain region of Serra do Cipó,South-eastern Brazil.We assessed soil,slope,and vegetation types,and calculated richness and beta-diversity,applying generalized least square models,linear mixed-models and partial Mantel tests to test for relationships.Richness of graminoids and herbaceous species increased with greater elevation and more nutrient-impoverished soils,while woody richness showed the inverse pattern.Beta-diversity was primarily driven by species turnover,correlated with elevation and soil and higher in less dominant vegetation types,with unique species.Despite the limited elevational range in these old mountains,it still played an important role in filtering woody species,while fostering graminoid and herbaceous species.Conservation and restoration actions need to foster the high regional diversity supported by the old mountain heterogeneous landscape and the diversity of life-forms,especially the dominant and highly diverse grassy component. 展开更多
关键词 BETA-DIVERSITY Campos rupestres CERRADO Grassland HERBACEOUS Species turnover
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Influence of local and landscape environmental factors on alpha and beta diversity of macroinvertebrates in Andean rivers
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作者 DIAZ-ROJAS Camila A PEDROZA-RAMOS Adriana X +1 位作者 BARRERA-HERRERA July A ROA-FUENTES Camilo A 《Journal of Mountain Science》 SCIE CSCD 2023年第9期2487-2501,共15页
Research on macroinvertebrate community structure in Andean rivers has been oriented towards describing patterns of alpha and gamma diversity by taking into account environmental predictors at local spatial scales(e.g... Research on macroinvertebrate community structure in Andean rivers has been oriented towards describing patterns of alpha and gamma diversity by taking into account environmental predictors at local spatial scales(e.g.,micro-and mesohabitats).However,the patterns of beta diversity and the importance of landscape-scale variables have been evaluated to a lesser extent.The objective of this study was to describe the patterns of alpha and beta diversity of benthic macroinvertebrates in the Andean rivers of the Orinoco basin and their relationship with local and landscape environmental variation.A stratified random sampling of macroinvertebrates was carried out at 40 sites(comprising an altitudinal range of between 500 and 2900 m.a.s.l.),local and landscape variables were measured.Our results showed that the variation of alpha diversity was influenced by local and landscape variables,which are directly and indirectly related to the contribution of sediments,substrate composition and flow velocity,providing a heterogeneity of habitats.Global beta diversity was explained by the combined effect of local and landscape variables.Regarding the beta diversity phenomena,turnover was predominant while nestedness presented a minor contribution and both were explained in greater proportion by local descriptors and some landscape variables,specifically those of a geomorphological nature.Our results concur with the view of an environmental and spatial hierarchy within the river habitat and highlight the influence of multiple scales on macroinvertebrate diversity.The above suggests that both local and landscape scales must necessarily be considered for environmental management and the conservation of Andean lotic ecosystems. 展开更多
关键词 Andean lotic systems Andean agroecosystems Instream habitat Landcover TURNOVER NESTEDNESS
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Eff ects of stand condition and root density on fi ne-root dynamics across root functional groups in a subtropical montane forest
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作者 Lin Huang Rudong Zhao +3 位作者 Xiaoxiang Zhao Qiuxiang Tian Pengyun Yue Feng Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期665-675,共11页
Fine roots play key roles in belowground C cycling in terrestrial ecosystems.Based on their distinct functions,fi ne roots are either absorptive fi ne roots(AFRs)or transport fi ne roots(TFRs).However,the function-bas... Fine roots play key roles in belowground C cycling in terrestrial ecosystems.Based on their distinct functions,fi ne roots are either absorptive fi ne roots(AFRs)or transport fi ne roots(TFRs).However,the function-based fi ne root dynamics of trees and their responses to forest stand properties remain unclear.Here,we studied the dynamics of AFRs and TFRs and their responses to stand conditions and root density in a subtropical montane mixed forest based on a 2-a root window experiment.Mean(±SE)annual production,mortality,and turnover rate of AFRs were 7.87±0.17 m m^(−2)a^(−1),8.13±0.20 m m^(−2)a^(−1)and 2.96±0.24 a^(−1),respectively,compared with 7.09±0.17 m m^(−2)a^(−1),4.59±0.17 m m^(−2)a^(−1),and 2.01±0.22 a^(−1),respectively,for TFRs.The production and mortality of fi ne roots were signifi cantly higher in high root-density sites than in low-root density sites,whereas the turnover of fi ne roots was faster in the low root-density sites.Furthermore,root density had a larger positive eff ect than other environmental factors on TFR production but had no obvious impact on AFR production.Tree species diversity had an apparent positive eff ect on AFR production and was the crucial driver of AFR production,probably due to a complementary eff ect,but had no evident impact on TFR.Both tree density and tree species diversity were positively correlated with the mortality of AFRs and negatively related to the turnover of TFRs,suggesting that higher root density caused stronger competition for rooting space and that plants tend to reduce maintenance costs by decreasing TFR turnover.These fi ndings illustrated the importance of root functional groups in understanding root dynamics and their responses to changes in environmental conditions. 展开更多
关键词 Root functional group Root production Root mortality Root turnover Stand condition Badagongshan mountain
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Applying zeta diversity to understand species turnover patterns of small mammals in the Mountains of Southwest China
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作者 Jin-Zhao Ke Zhi-Xin Wen +4 位作者 Ming-Qiang Wang Anderson Feijó Tian Tian Lin Xia Qi-Sen Yang 《Zoological Research》 SCIE CSCD 2023年第5期939-942,共4页
DEAR EDITOR,Mountainous regions are generally characterized by high species turnover,yet studies applying novel conceptual frameworks to analyze the spatial structure and organization of montane biota along elevationa... DEAR EDITOR,Mountainous regions are generally characterized by high species turnover,yet studies applying novel conceptual frameworks to analyze the spatial structure and organization of montane biota along elevational gradients remain scarce.Based on the zeta diversity framework—a novel turnover metric that focuses on average number of species shared across sites—and a comprehensive presence-absence dataset of small mammals collected from 22 elevational gradients in the Mountains of Southwest China(MSC). 展开更多
关键词 MAMMALS MOUNTAINS TURNOVER
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Patterns of species richness and beta diversity of vascular plants along elevation gradient in Brazilian páramo
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作者 CORDEIRO Anais de Almeida Campos KLANDERUD Kari +1 位作者 VILLA Pedro Manuel NERI Andreza Viana 《Journal of Mountain Science》 SCIE CSCD 2023年第7期1911-1920,共10页
Understanding the relationships between plant diversity and the environment is an important step towards conservation of species and ecosystems.In this study,we hypothesize that community species richness decreases an... Understanding the relationships between plant diversity and the environment is an important step towards conservation of species and ecosystems.In this study,we hypothesize that community species richness decreases and species composition change along the elevation gradient,with a greater contribution of species turnover than nestedness to beta diversity.We surveyed plant species in 300 plots(1 m×1 m)in four elevational bands(2100 m,2300m,2500 m,and 2700 m)in the CaparaóNational Park,Southeastern Brazil.The samples presented a great number of species(97 spp.,59 genera,27families),however,74%of the species were considered rare with their relative abundance being<1%.Among the four bands along the gradient,we detected two distinct communities with few species in common.The transition between the two communities occurred at 2500 m,and this elevation band also had the highest species richness in total.A non-metric multidimensional scaling(NMDS)showed floristic differences between the bands even though they had similar richness.In 89%of the plot pairs,using pairwise comparison of species composition,only half of the species that occurred in one did occur in the other plot.The dissimilarity among the plots and elevational band reflects a significant contribution of spatial species turnover to the species richness and beta diversity on the Caparaómountain.Beta diversity increased with spatial scale(from plot to elevational-band).The dissimilarity(βSOR=0.907)in the area was due almost exclusively to spatial species turnover(βSIM=0.879),with very low contribution of species nestedness(βSNE=0.028).Our research showed that species richness does not decrease with elevation in the study area,but the floristic composition changes.The clear distinction of species along the gradient show that spatial species turnover is the major diversitygenerating process in the studied area. 展开更多
关键词 High altitude grassland Species turnover Partitioning diversity Campo de altitude Tropical mountains
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Mental Health Intervention in the Workplace amidst the COVID-19 Pandemic
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作者 Tayarka Kendrick James B. Artley Bahaudin G. Mujtaba 《Health》 CAS 2023年第4期289-311,共23页
The purpose of this project is to examine why the mental health of employees should be prioritized in the workplace. Most employees have likely experienced a visible illness or injury at some point during their career... The purpose of this project is to examine why the mental health of employees should be prioritized in the workplace. Most employees have likely experienced a visible illness or injury at some point during their careers. It is easier to identify these physical ailments that may adversely affect an employee’s performance at work, such as a broken leg or the common cold. However, there are conditions that are much less visible that negatively impact employees every day, and mental health is one of them. A person’s mental health is a significant factor in their work life that should not be ignored. While it may be difficult to recognize when someone is struggling with depression, anxiety, or another form of mental illness on the surface, employers should not automatically assume their entire staff is okay. As a result of the COVID-19 pandemic coupled with an increase in civil unrest in society, employers must reevaluate the way they conduct business, starting with the treatment of their employees. To aid employers with prioritizing mental health at work, this paper’s objectives are to address the stigma associated with mental health issues/illness, develop recommendations for inclusive work environments, increase an employer’s investment in mental health, reduce employee turnover, and normalize respect in the workplace. The findings are discussed, and recommendations are provided. Employers who intentionally prioritize and invest in their employees’ mental health will significantly reduce the costs associated with attracting and recruiting new staff due to high turnover rates. Additionally, their reputation as a preferred employer will increase. 展开更多
关键词 Mental Health Stress Depression Employee Turnover COVID-19 Pandemic Disability Stigma RESIGNATION Quiet Quitting
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Improved Catalytic Reaction of Biotemplated Palladium Nanoparticles through Immobilized Metal Affinity Purification
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作者 Shadrach Ibinola Hazim Aljewari +1 位作者 Imann Mosleh Robert Beitle 《Advances in Nanoparticles》 CAS 2023年第1期22-31,共10页
To investigate the effect purification plays on nanoparticle (NP) synthesis and catalytic activity, three copies of Pd4 (TSNAVHPTLRHL) fused to the N-terminus of Green Fluorescent Protein (GFP) was produced recombinan... To investigate the effect purification plays on nanoparticle (NP) synthesis and catalytic activity, three copies of Pd4 (TSNAVHPTLRHL) fused to the N-terminus of Green Fluorescent Protein (GFP) was produced recombinantly and its characteristics pre and post purification was assessed. An E. coli expression system was employed, and purification was performed with Immobilized Metal Affinity Column (IMAC). Transmission electron microscopy (TEM) was utilized to examine the morphology of NPs synthesized with an enriched protein sample and ImageJ was used to determine the average size to be 2.44 nm. The turnover frequency of fabricated NP from the purified protein was analyzed by a model Suzuki-Miyaura coupling reactions and determined to be 33,000 hr<sup>-1</sup>. This value is three times higher than the turnover frequency when crude lysate containing (Pd4)<sub>3</sub>-GFP was used during NP synthesis. This result shows that enrichment enhanced the catalytic activity of NP. 展开更多
关键词 Protein Expression Nanoparticle Synthesis Turnover Frequency SUZUKI-MIYAURA
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The Impact of Saudi Nurses’ Happiness on Their Turnover Intentions
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作者 Hana K. Alotheimin Olfat Salem 《Open Journal of Nursing》 2023年第11期800-810,共11页
Highly happy nurses are more productive, engaged and loyal. If nurses are satisfied, then their intention to leave is low. Aim: to investigate the impact of Saudi nurses’ happiness on their intention to turnover in t... Highly happy nurses are more productive, engaged and loyal. If nurses are satisfied, then their intention to leave is low. Aim: to investigate the impact of Saudi nurses’ happiness on their intention to turnover in the Kingdom of Saudi Arabia. Research Hypothesis: H0. There is no relationship between the nurses’ happiness on their intention to turnover among Saudi nurses. H1. The happy Saudi nurses will have a lower turnover intention among Saudi nurses in the Medina region. Design: Quantitative, cross-sectional, and correlational study designs have been used. Setting: Big public hospital in Medina from June to October 2022. Sample: A quota, convenience sample of 281 Saudi nurses. Tools: A. Oxford happiness inventory to measure the nurses’ happiness. B. Turnover Intention Scale to evaluate the Saudi nurses’ intention to leave their current job. Results: More than half of the nurses had moderate happiness, but more than 75% of the Saudi nurses had a desire to leave. The relationship between happiness and turnover intentions is negative. Conclusion: Magnet-like work environments in Saudi Arabia are critical to recruit and retain nurses with critical nursing shortages. Recommendations: Encourage governmental policy-makers to formulate national policies and KPIs in order to make them happy and retain them. . 展开更多
关键词 Saudi Nurses HAPPINESS Turnover Intention
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An Analysis of Amazon’s High Turnover Rate
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作者 Tian Chen 《Proceedings of Business and Economic Studies》 2023年第3期31-38,共8页
Amazon’s internal and external environments were analyzed using PEST and SWOT models.Taking into account of relevant literature on strategic human resource management(SHRM)and models like the Harvard model and the hu... Amazon’s internal and external environments were analyzed using PEST and SWOT models.Taking into account of relevant literature on strategic human resource management(SHRM)and models like the Harvard model and the human resource management/industrial relation(HRM/IR)model,the reasons for Amazon’s employee high turnover rate were analyzed.In this paper,several solutions to this issue are indicated,including improving incentive policies and organizing training.At the end of this paper,my personal experiences and the lessons learned throughout the course are summarized. 展开更多
关键词 High turnover rate INCENTIVE Emotional identity
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心理契约对基层全科医师工作绩效的影响机制:离职倾向的中介调节作用 被引量:2
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作者 时婷婷 缪清清 +8 位作者 曹欣 付钰赛 詹祥 张子楠 李富 陈家应 胡丹 杨帆 唐卫卫 《中国卫生资源》 北大核心 2022年第6期847-852,共6页
目的 分析心理契约对基层全科医师工作绩效的影响机制,探析离职倾向在其中的中介调节作用,为基层全科医师队伍建设提供依据。方法 采用问卷调查对南京市浦口区基层医疗卫生机构的全科医师进行调研,收集其社会人口学信息,测量其心理契约... 目的 分析心理契约对基层全科医师工作绩效的影响机制,探析离职倾向在其中的中介调节作用,为基层全科医师队伍建设提供依据。方法 采用问卷调查对南京市浦口区基层医疗卫生机构的全科医师进行调研,收集其社会人口学信息,测量其心理契约、工作绩效和离职倾向水平,拟合多重线性回归模型分析作用机制和中介调节效应,验证本研究的4个研究假设。结果 基层全科医师心理契约对工作绩效存在正向促进作用(b=0.554,P<0.001)。纳入离职倾向后,心理契约和队伍稳定性对于工作绩效均存在正向促进作用(b=0.285、0.357,P<0.001)。纳入心理契约和离职倾向的交互项后,交互项的偏回归系数差异具有统计学意义(b=-0.013,P=0.006),说明低离职倾向抑制了心理契约提升工作绩效的正向作用。结论 应重视基层全科医师内在情感(即心理契约)的激励作用,采用多举措降低离职意愿,提升职业认同,避免发生“出工不出力”现象,促进工作绩效提升和基层全科医师队伍稳定。 展开更多
关键词 基层primary 全科医师general practitioner 工作绩效work performance 心理契约psychological contract 离职倾向turnover intention 中介调节作用mediated moderation effect
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上海某区区属公立医疗卫生机构护理人员离职倾向及其影响因素 被引量:2
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作者 李星星 王伟 +3 位作者 臧召燕 王艺园 孙艳春 严非 《中国卫生资源》 北大核心 2022年第2期193-198,共6页
目的 调查上海某区区属公立医疗卫生机构在岗护理人员的离职倾向并分析其影响因素,为提升护理队伍的稳定性提供参考。方法 采用一般情况调查表和离职倾向量表对上海某区区属公立医疗卫生机构中一半的护理人员进行匿名问卷调查,共收集问... 目的 调查上海某区区属公立医疗卫生机构在岗护理人员的离职倾向并分析其影响因素,为提升护理队伍的稳定性提供参考。方法 采用一般情况调查表和离职倾向量表对上海某区区属公立医疗卫生机构中一半的护理人员进行匿名问卷调查,共收集问卷3 756份,最终纳入分析3 206份。结果 调查对象的离职倾向得分中位数(第25百分位数,第75百分位数)为11.0(6.0,14.0)分,离职倾向总体较高。不同机构类型、年龄、婚姻状况、最高学历、工作年数、聘用形式、职称、月均收入的护理人员的离职倾向得分差异分别有统计学意义(P<0.05)。多因素分析结果显示,机构类型、年龄和月均收入是影响护理人员离职倾向的主要因素(P<0.05)。结论 上海某区区属公立医疗卫生机构在岗护理人员离职倾向总体较高。就职于二级综合医院、年轻、低收入的护理人员应成为重点关注人群。建议二级医疗机构结合政策导向发展自身:营造良好的组织氛围,变革领导方式;合理开源,公平分配绩效,以提升护理人员的职业认同感、拓宽护理人员的发展路径,提高护理人员的收入。 展开更多
关键词 护理人员nursing staff 离职倾向turnover intention 影响因素influencing factor 公立医疗卫生机构public medical and healthcare institution
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A cross-sectional study on nurse turnover intention and influencing factors in Jiangsu Province, China 被引量:17
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作者 Hongying Chen Guohong Li +2 位作者 Mengting Li Lei Lyu Tiantian Zhang 《International Journal of Nursing Sciences》 2018年第4期396-402,共7页
Background:Nurses'turnover has been a major concern globally,which is strongly influenced by nurses'intent to leave.However,only a few large sample studies on the predictive factors associated with nurses'... Background:Nurses'turnover has been a major concern globally,which is strongly influenced by nurses'intent to leave.However,only a few large sample studies on the predictive factors associated with nurses'turnover intention were conducted in Jiangsu Province.This study mainly aims to examine the level and factors that influence nurses to leave their work in Jiangsu Province of Eastern China.Methods:A cross-sectional survey of 1978 nurses was conducted at 48 hospitals in 14 key cities throughout Jiangsu Province.The turnover intention in nurses was measured by the scale of intent to leave the profession.The work environment of nurses was measured by the Chinese version of the Practice Environment Scale.A multiple linear regression model was applied to analyse the factors associated with turnover intention.Results:The resignation rate of nurses in the hospitals of Jiangsu Province ranged from 0.64%to 12.71%in 2016.The mean scores were 15.50±3.44 for turnover intention,and 3.06±0.51 for work environment.Involvement in hospital affairs,resource adequacy,age,professional title,year(s)working,employment type and education level were the predictors of nurse intent to leave(P<0.05).Conclusion:The work environment of nurses in hospitals must be improved in staffing and resource and nurses'involvement in hospital affairs.The current study corroborates that nurses have high turnover intention.Thus,effective measures are needed to improve nurse accomplishment,professional status,participation in hospital affairs and career planning to reduce their turnover intention. 展开更多
关键词 China NURSE Root cause analysis Turnover intention Work environment
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