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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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Dietary xylo‑oligosaccharides and arabinoxylans improved growth efficiency by reducing gut epithelial cell turnover in broiler chickens 被引量:1
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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 被引量:1
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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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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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Effects of improved amino acid balance diet on lysine mammary utilization, whole body protein turnover and muscle protein breakdown on lactating sows
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作者 Sai Zhang Juan C.Marini +4 位作者 Vengai Mavangira Andrew Claude Julie Moore Mahmoud A.Mohammad Nathalie L.Trottier 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2031-2043,共13页
Background The study objective was to test the hypothesis that low crude protein(CP)diet with crystalline amino acids(CAA)supplementation improves Lys utilization efficiency for milk production and reduces protein tur... Background The study objective was to test the hypothesis that low crude protein(CP)diet with crystalline amino acids(CAA)supplementation improves Lys utilization efficiency for milk production and reduces protein turnover and muscle protein breakdown.Eighteen lactating multiparous Yorkshire sows were allotted to 1 of 2 isocaloric diets(10.80 MJ/kg net energy):control(CON;19.24%CP)and reduced CP with“optimal”AA profile(OPT;14.00%CP).Sow body weight and backfat were recorded on d 1 and 21 of lactation and piglets were weighed on d 1,14,18,and 21 of lactation.Between d 14 and 18,a subset of 9 sows(CON=4,OPT=5)was infused with a mixed solution of 3-[methyl-2H3]histidine(bolus injection)and[13C]bicarbonate(priming dose)first,then a constant 2-h[13C]bicarbonate infusion followed by a 6-h primed constant[1-13C]lysine infusion.Serial blood and milk sampling were performed to determine plasma and milk Lys enrichment,Lys oxidation rate,whole body protein turnover,and muscle protein breakdown.Results Over the 21-d lactation period,compared to CON,sows fed OPT had greater litter growth rate(P<0.05).Compared to CON,sows fed OPT had greater efficiency of Lys(P<0.05),Lys mammary flux(P<0.01)and whole-body protein turnover efficiency(P<0.05).Compared to CON,sows fed OPT tended to have lower whole body protein breakdown rate(P=0.069).Muscle protein breakdown rate did not differ between OPT and CON(P=0.197).Conclusion Feeding an improved AA balance diet increased efficiency of Lys and reduced whole-body protein turnover and protein breakdown.These results imply that the lower maternal N retention observed in lactating sows fed improved AA balance diets in previous studies may be a result of greater partitioning of AA towards milk rather than greater body protein breakdown. 展开更多
关键词 Amino acid Efficiency Lactating sows Protein breakdown Protein turnover Reduced protein diet
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Nurses’job embeddedness and turnover intention:A systematic review and meta-analysis
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作者 Xin Wang Ming Liu +3 位作者 Angela Y.M.Leung Xiaoyan Jin Hongxia Dai Shaomei Shang 《International Journal of Nursing Sciences》 CSCD 2024年第5期563-570,I0003,共9页
Objective:This study aimed to review the relationship between job embeddedness and turnover intentions among nurses and explore the effects of the Job Embeddedness Scale,number of years in the career,education,and mar... Objective:This study aimed to review the relationship between job embeddedness and turnover intentions among nurses and explore the effects of the Job Embeddedness Scale,number of years in the career,education,and marital status on this relationship.Methods:The review was conducted by searching the China Knowledge Resource Integrated Database(CNKI),Weipu Database(CQVIP),China Biology Medicine(CBM),Wanfang Database,PubMed,Web of Science,Embase,CINAHL,and APA-PsycNet for articles on nurses’job embeddedness and turnover from intention up to March 2024.The research quality was evaluated using the Agency for Healthcare Research and Quality(AHRQ)assessment criteria.The review protocol has been registered on PROSPERO[CRD42023483947].Results:The results of this review included 47 studies consisting of 15,742 nurses from seven countries worldwide.A moderate negative correlation was found between job embeddedness and turnover intention(r=0.487).Furthermore,on-the-job embeddedness(r=0.527)was more negatively associated with turnover intention than off-the-job embeddedness(r=0.234).The highest negative correlation was found between sacrifice and turnover intention(r=0.460),while the lowest was for the link(r=0.185).Furthermore,the relationship between job embeddedness and its dimensions with turnover intention was affected by different job embeddedness scales,number of years in the career,education,and marital status(P<0.05).Conclusion:This systematic review and meta-analysis analyzed the relationships between nurses’job embeddedness,dimensions,and turnover intention.Meanwhile,subgroup analysis and meta-regression explored the factors influencing these relationships.It is an important reference for nurse managers to promote nurse retention. 展开更多
关键词 Job embeddedness META-ANALYSIS Nurses Turnover intention
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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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Unveiling osteoprotective potential of biologically active naringenin in rats with dexamethasone-induced osteoporosis
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作者 Tejal R.Waykar Satish K.Mandlik Deepa S.Mandlik 《Digital Chinese Medicine》 CAS CSCD 2024年第2期171-183,共13页
Objective To investigate the protective effects of naringenin(NRG)against dexamethasone(DEX)-induced osteoporosis(OP)in rats.Methods Molecular docking of NRG was done with AutoDock Vina 1.2.0 software.Forty-eight fema... Objective To investigate the protective effects of naringenin(NRG)against dexamethasone(DEX)-induced osteoporosis(OP)in rats.Methods Molecular docking of NRG was done with AutoDock Vina 1.2.0 software.Forty-eight female Wistar rats were randomly divided into six groups(n=8 each):normal control(NC),DEX(7 mg/kg,i.m.),NRG-low(NRG-L;25 mg/kg,i.g.),NRG-medium(NRG-M;50 mg/kg,i.g.),NRG-high(NRG-H;100 mg/kg,i.g.),and alendronate(ALN;0.25 mg/d,i.g.)groups.OP was induced by administering DEX once a week for five weeks in all groups except NC group.Begining in the third week after the initial DEX administration,the rats in NRG-L,NRG-M,NRG-H,and ALN groups received the corresponding treatments daily for three weeks,while NC and DEX groups received no additional treatment.Serum samples were collected at the end of the experiment for biochemical,bone turnover,antioxidant,lipid profile,and inflammatory cytokine analyses.Femur bones underwent physical parameter testing and histopathological examination.Results The molecular docking results illustrated that NRG docked with calcitonin(CT),lowdensity lipoprotein(LDL),bone morphogenetic protein(BMP),vascular endothelial growth factor(VEGF)receptor,forkhead transcription factors,and osteoprogenitor cells showed good binding energy.In rats administered with 25,50,and 100 mg/kg NRG,there was a significant enhancement in serum biochemical indices,characterized by a reduction in tartrate-resistant acid phosphatase(TRAP),parathyroid hormone(PTH),and an elevation in osteocalcin(OC)and CT levels(P<0.05,P<0.01,and P<0.001,respectively).Despite no significant changes in thickness,weight,and length(P>0.05),there was a marked increase in bone mineral density(BMD)(P<0.01,P<0.001,and P<0.001,respectively).Antioxidant enzyme markers showed significant upregulation,with higher glutathione,superoxide dismutase,and catalase,and a concurrent decrease in malondialdehyde(MDA)(P<0.05,P<0.01,and P<0.001,respectively).The lipid profile also improved significantly,with lower cholesterol(CH),triglycerides(TG),and low-density lipoprotein(LDL)levels,and an increase in high-density lipoprotein(HDL)level(P<0.05,P<0.01,and P<0.001,respectively).Inflammatory cytokine levels were reduced,as evidenced by decreases in tumor necrosis factor(TNF),interleukin(IL)-6,and IL-1β(P<0.05,P<0.01,and P<0.001,respectively).Furthermore,histological alterations revealed obvious improvements,and the body weight of rats treated with NRG showed an increase compared with DEX group.Conclusion These findings imply that NRG exhibited a protective effect against DEX-induced OP in rats as it promotes the bone formation process by increasing the number of bone turnover markers including OC and CT,and restoring of antioxidant status,lipid metabolism,and inflammatory markers. 展开更多
关键词 NARINGENIN OSTEOPOROSIS DEXAMETHASONE Bone turnover markers Inflammatory cytokines
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Evaluation of New Graduate Nursing Orientation Program
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作者 Elizabeth Arroyo 《Open Journal of Nursing》 2024年第8期433-446,共14页
The study site is a holistic patient-centered organization that has developed a 16-week long orientation program for new graduate nurses entering the hospital setting. The purpose of the program is for new graduate nu... The study site is a holistic patient-centered organization that has developed a 16-week long orientation program for new graduate nurses entering the hospital setting. The purpose of the program is for new graduate nurses to gain the confidence, competence, and critical thinking skills for providing safe patient care. The issue occurring within the organization is that there is an increasing rise in the number of turnover rates of new graduates leaving the hospital, thus making evaluating the program a necessity to problem-solving. There has been no evaluation of the program in the past five years to reveal why the increase in the recent turnover rates. The data collected during the interview process was coded and categorized into three main sections: organizational, substantive, and theoretical. The evaluator used an organizational category to investigate for board areas or issues within the problem attempting to be solved. The evaluator concluded from the results and findings that the issue, a poor preceptor-preceptee relationship was seen by all stakeholders involved. The literature presented concludes that continuous evaluation of orientation programs is crucial for the professional and personal growth of new graduate nurses in the hospital. 展开更多
关键词 New Graduate Nurses PRECEPTORS TURNOVER ORIENTATION
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Factors Promoting Retention of Nurses in Three Private Hospitals of Lahore: A Cross Sectional Descriptive Survey
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作者 Zainab Suleman Najma Balquees Anwar +3 位作者 Sadaf Younis Alya Bilquees Anwar Naeema Khan Syed Saemul Hassan 《Open Journal of Nursing》 2024年第7期344-367,共24页
Introduction: Pakistan has a large number of professional nurses but a higher rate of turnover contributes towards the shortage of nurses which is intensified by nurses’ immigration, lack of recruitment of new nurses... Introduction: Pakistan has a large number of professional nurses but a higher rate of turnover contributes towards the shortage of nurses which is intensified by nurses’ immigration, lack of recruitment of new nurses and retirement of senior nurses. Aim: The study aimed at examining the factors that increase retention of nurses. Research Method: The study is descriptive cross sectional with a sample of 150 nurses including both the genders, from 3 private hospitals located in Pakistan. A convenient sampling technique was used. The data collection was done through close ended questionnaires based on 20 questions. Data collection was done quantitatively and then data was entered in SPSS. Correlation and regression tests were performed. Findings: The analysis revealed that 91.3% nurses are loyal to their hospitals but, 8.7%nurses can switch the hospital for different reasons. It was also found that the idea of leaving the job based on the intention of moving to abroad and public sector was higher than the retirement and other causes. Resultantly, enhancements in nurses’ work environments have the ability to decrease nurses’ job burnout and turnover and increase patients’ satisfaction. Recommendations: Hospital leaders should implement effective strategies to encourage nurses to continue their job by motivation, strengthening management skills within the hospital and improving a positive work environment by promoting teamwork, continuous learning, trust, respect and flexible arrangements which can lead towards achieving better results.However, further studies quantitatively and qualitatively can explore more factors related to dissatisfaction of nurses. Health systems policy makers should lead by developing related strategies for the retention of nurses. 展开更多
关键词 Retention of Nurses Shortage of Nurses TURNOVER Workforce
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Vietnam's textile and garment export turnover hits 44 billion USD in 2024
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《China Textile》 2024年第6期42-42,共1页
Vietnam's textile and garment industry has fulfilled its 44-billion-USD export turnover target in 2024,an increase of over 11%compared to 2023,thanks to efforts in market diversification,technological innovation,a... Vietnam's textile and garment industry has fulfilled its 44-billion-USD export turnover target in 2024,an increase of over 11%compared to 2023,thanks to efforts in market diversification,technological innovation,and effectively capitalising on the shift in orders. 展开更多
关键词 TURNOVER VIETNAM GARMENT
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Soil Carbon Balance in a Native Temperate Grassland in the Xilin River Basin of Inner Mongolia 被引量:3
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作者 李凌浩 韩兴国 +8 位作者 王其兵 白文明 白永飞 闫志丹 陈全胜 张焱 杨晶 李鑫 宋世环 《Acta Botanica Sinica》 CSCD 2002年第6期740-742,共3页
Based on historical data and field investigation, some major fluxes and reserves of carbon were estimated, and a tentative analysis of the soil carbon balance was made in a native grassland community in the Xilin Rive... Based on historical data and field investigation, some major fluxes and reserves of carbon were estimated, and a tentative analysis of the soil carbon balance was made in a native grassland community in the Xilin River basin of Inner Mongolia. Major results were reported as follows: 1) Annual average carbon input from above-ground biomass production was 79.8 g C(.)m(-2.)a(-1), and from root biomass to 30 cm. depth averaged 311.9 g C(.)m(-2.)a(-1). The summed mean annual carbon input of shoot and root materials in the study site was approximately 391.7 g C(.)m(-2.)a(-1). 2) The annual amount of above-ground biomass consumed by insects averaged 14.7 g C(.)m(-2.)a(-1), and the carbon output by leaching or light-chemical oxidation was 3.2 g C(.)m(-2.)a(-1) The annual evolution rate of CO2 from net soil respiration averaged 346.9 g C(.)m(-2.)a(-1), and the summed mean annual output was approximately 364.8 g C(.)m(-2.)a(-1). 3) A mature, steady-state system could be assumed for the community for which growth and decay were approximately in balance, with a net carbon accumulation of about 26.9 g C(.)m(-2.)a(-1). Based on the soil organic carbon density of the field, the turnover Irate of soil carbon in 0 - 30 cm depth was calculated to be 6.2%, with a turnover time of 16 years. 展开更多
关键词 Leymus chinensis steppe carbon balance soil respiration turnover rate net primary productivity (NPP)
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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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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:4
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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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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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Matrix metalloproteinase-2 and tissue inhibitor of metallo-proteinase-2 in colorectal carcinoma invasion and metastasis 被引量:21
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作者 Bing-HuiLi PengZhao Shi-ZhengLiu Yue-MingYu MeiHan Jin-KunWen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第20期3046-3050,共5页
AIM: To explore the relationship between matrix metallopr- oteinase-2 (MMP-2) and tissue inhibitor of metallopr- oteinase-2 (TIMP-2) in the development of colorectal carcinoma and to provide a valuable marker for clin... AIM: To explore the relationship between matrix metallopr- oteinase-2 (MMP-2) and tissue inhibitor of metallopr- oteinase-2 (TIMP-2) in the development of colorectal carcinoma and to provide a valuable marker for clinical diagnosis. METHODS: Twenty-five patients with colorectal carcinoma underwent surgical resection. Samples were taken from tumor sites and normal tissues. MMP-2 activity was determined by gelatin zymography. Western blot and ABC immunohist-ochemical staining were used to detect the expression levels of MMP-2 and TIMP-2 in normal and colorectal carcinoma tissues. Statistical analyses were performed using the Student's t test and one-way ANOVA. P<0.05 was considered statistically .significant. All the statistical analyses were performed using SPSS 10.0 software. RESULTS: MMP-2 activity could be detected in both normal and colorectal carcinoma tissues. MMP-2 activity in colorectal carcinoma tissues was much higher than that in normal tissues (P<0.05, t=3.916,4.227). MMP-2 activity was positively related to the colorectal carcinoma invasion depth, lymph node metastasis and Duke's stage. Western blot and ABC immunohistochemical staining demonstrated that the expression level of MMP-2 in colorectal carcinoma tissues was much higher than that in normal tissues (P<0.05, t = 9.429), but the expression level of TIMP-2 in colorectal carcinoma tissues was much lower than that in normal tissues (P<0.05, t = 7.329). The MMP-2/TIMP-2 ratio of colorectal carcinoma was much higher than that of normal tissues. With the progression of invasion depth, lymph node metastasis and tumor Duke's stage, the activity and expression level of MMP-2 and TIMP-2 gradually increased, but the MMP-2/TIMP-2 ratio gradually decreased. CONCLUSION: The balance between MMP-2 and TIMP-2 plays a crucial role in the process of colorectal carcinoma invasion and metastasis. 展开更多
关键词 Extracellular matrix turnover Colorectal carcinoma METASTASIS
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Correlation between growth differentiation factor-15 and collagen metabolism indicators in patients with myocardial infarction and heart failure 被引量:15
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作者 Fang-Fang WANG Bao-Xia CHEN +3 位作者 Hai-Yi YU Lin MI Zi-Jian LI Wei GAO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第1期88-93,共6页
BackgroundGrowth differentiation factor (GDF)-15, a divergent member of the transforming growth factor beta super-family does appear to be up-regulated in response to experimental pressure overload and progression o... BackgroundGrowth differentiation factor (GDF)-15, a divergent member of the transforming growth factor beta super-family does appear to be up-regulated in response to experimental pressure overload and progression of heart failure (HF). HF frequently develops after myocardial infarction (MI), contributing to worse outcome. The aim of this study is to assess the correlation between GDF-15 levels and markers related to collagen turnover in different stages of HF.MethodsThe study consists of a cohort of 179 patients, including stable angina pectoris patients (AP group,n= 50), old MI patients without HF (OMI group,n = 56), old MI patients with HF (OMI-HF group,n= 38) and normal Control group (n = 35). Both indicators reflecting the synthesis and degradation rates of collagen including precollagen I N-terminal peptide (PINP), type I collagen carboxy-terminal peptide (ICTP), precollagen III N-terminal peptide (PIIINP) and GDF-15 were measured using an enzyme-linked inmunosorbent assay.ResultsThe plasma GDF-15 level was higher in OMI-HF group (1373.4 ± 275.4 ng/L) than OMI group (1036.1 ± 248.6 ng/L), AP group (784.6 ± 222.4 ng/L) and Control group (483.8 ± 186.4 ng/L) (P〈 0.001). The indi-cators of collagen turnover (ICTP, PINP, PIIINP) all increased in the OMI-HF group compared with Control group (3.03 ± 1.02μg/Lvs. 2.08 ± 0.95μg/L, 22.2 ± 6.6μg/Lvs. 16.7 ± 5.1μg/L and 13.2 ± 7.9μg/Lvs. 6.4 ± 2.1μg/L, respectively;P〈 0.01). GDF-15 positively cor-related with ICTP and PIIINP (r = 0.302,P〈 0.001 andr= 0.206,P= 0.006, respectively). GDF-15 positively correlated to the echocardio-graphic diastolic indicators E/Em and left atrial pressure (r= 0.349 and r= 0.358, respectively;P〈 0.01), and inversely correlated to the systolic indicators left ventricular ejection fraction and the average of peak systolic myocardial velocities (Sm) (r=-0.623 and r=-0.365, respectively;P〈 0.01).ConclusionPlasma GDF-15 is associated with the indicators of type I and III collagen turnover. 展开更多
关键词 Biomarkers Collagen turnover Growth differentiation factor- 15 Heart failure Myocardial infarction
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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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Global comparisons of beta diversity among mammals,birds,reptiles,and amphibians across spatial scales and taxonomic ranks 被引量:11
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作者 Hong QIAN 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期509-514,共6页
Beta diversity is the change in species composition among areas in a geographic region. The proportion of species shared between two areas often decreases when the distance separating them increases, leading to an inc... Beta diversity is the change in species composition among areas in a geographic region. The proportion of species shared between two areas often decreases when the distance separating them increases, leading to an increase in beta diversity. This study compares beta diversity among four classes of terrestrial vertebrates (mammals, birds, reptiles, and amphibians) at both regional (biogeographic realm) and global extents, using the same sets of faunal sample units for all four groups in each comparison. Beta diversity is lower for the two endothermic taxa (birds and mammals) than for the two ectothermic taxa (reptiles and amphibians) in all six biogeographic realms examined. When the four taxa in the six biogeographic realms are combined, beta diversity at the species rank is higher than that of the genus rank by a factor of 1.24, and is higher than that of the family rank by a factor of 1.85. The ratio of beta diversity at the genus rank to that at the family rank is 1.50. Beta diversity is slightly higher for ecoregions of 5000-99,999 km^2 than for ecoregions of 100,000-5,000,000 km^2. 展开更多
关键词 β-diversity dispersal limitation Jaccard index species turnover terrestrial vertebrates.
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