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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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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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Novel Early-Warning Model for Customer Churn of Credit Card Based on GSAIBAS-Cat Boost
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作者 Yaling Xu Congjun Rao +1 位作者 Xinping Xiao Fuyan Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第12期2715-2742,共28页
As the banking industry gradually steps into the digital era of Bank 4.0,business competition is becoming increasingly fierce,and banks are also facing the problem of massive customer churn.To better maintain their cu... As the banking industry gradually steps into the digital era of Bank 4.0,business competition is becoming increasingly fierce,and banks are also facing the problem of massive customer churn.To better maintain their customer resources,it is crucial for banks to accurately predict customers with a tendency to churn.Aiming at the typical binary classification problem like customer churn,this paper establishes an early-warning model for credit card customer churn.That is a dual search algorithm named GSAIBAS by incorporating Golden Sine Algorithm(GSA)and an Improved Beetle Antennae Search(IBAS)is proposed to optimize the parameters of the CatBoost algorithm,which forms the GSAIBAS-CatBoost model.Especially,considering that the BAS algorithm has simple parameters and is easy to fall into local optimum,the Sigmoid nonlinear convergence factor and the lane flight equation are introduced to adjust the fixed step size of beetle.Then this improved BAS algorithm with variable step size is fused with the GSA to form a GSAIBAS algorithm which can achieve dual optimization.Moreover,an empirical analysis is made according to the data set of credit card customers from Analyttica official platform.The empirical results show that the values of Area Under Curve(AUC)and recall of the proposedmodel in this paper reach 96.15%and 95.56%,respectively,which are significantly better than the other 9 common machine learning models.Compared with several existing optimization algorithms,GSAIBAS algorithm has higher precision in the parameter optimization for CatBoost.Combined with two other customer churn data sets on Kaggle data platform,it is further verified that the model proposed in this paper is also valid and feasible. 展开更多
关键词 Customer churn early-warning model IBAS GSAIBAS-CatBoost
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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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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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Variation patterns of fine root biomass, production and turnover in Chinese forests 被引量:5
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作者 Shaozhong Wang Zhengquan Wang Jiacun Gu 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第6期1180-1189,共10页
China's forests cover 208.3 million ha and span a wide range of climates and a large variety of forest types, including tropical, temperate, and boreal forests. However, the variation patterns of fine root (< 2... China's forests cover 208.3 million ha and span a wide range of climates and a large variety of forest types, including tropical, temperate, and boreal forests. However, the variation patterns of fine root (< 2 mm in diameter) biomass, production, and turnover from the south to the north are unclear. This study summarizes fine root biomass (FRB), production (FRP) and turnover rate (FRT) in China's forests as reported by 140 case studies published from 1983 to 2014. The results showed that the mean values of FRB, FRP and FRT in China's forests were 278 g m(-2), 366 g m(-2) a(-1), and 1.19 a(-1), respectively. Compared with other studies at the regional or global scales, FRB in China's forests was lower, FRP was similar to estimates at the global scale, but FRT was much higher. FRB, FRP, and FRT in China's forests increased with increasing mean annual precipitation (MAP), indicating that fine root variables were likely related to MAP, rather than mean annual temperature or latitude. This is possibly due to the small variation in temperature but greater variation in precipitation during the growing season. These findings suggest that spatiotemporal variation in precipitation has a more profound impact on fine root dynamics in China's forests, and this will impact carbon and nutrient cycles driven by root turnover in the future. 展开更多
关键词 Fine root biomass Fine root production Fine root turnover Climate change
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Trends of soil organic matter turnover in the salt marsh of the Yangtze River estuary 被引量:6
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作者 CHEN Qingqiang GU Hequan ZHOU Juzhen MENG Yi HU Kelin 《Journal of Geographical Sciences》 SCIE CSCD 2007年第1期101-113,共13页
Characteristics and tidal flat trends of soil organic matter (SOM) turnover were studied for the Chongmingdongtan Salt Marsh in the Yangtze River estuary, based on analyses of stable carbon isotope composition (δ^... Characteristics and tidal flat trends of soil organic matter (SOM) turnover were studied for the Chongmingdongtan Salt Marsh in the Yangtze River estuary, based on analyses of stable carbon isotope composition (δ^13C), grain sizes and contents of particulate organic carbon (POC), total nitrogen (TN) and inorganic carbon (TIC) for three cores excavated from high tidal flat, middle tidal flat and bare flat. Results demonstrate that correlations between soil POC contents and δ^13C values of the salt marsh cores were similar to those between soil organic carbon (SOC) contents and δ^13C values of the upper soil layers of mountainous soil profiles with different altitudes. SOM of salt marsh was generally younger than 100 years, and originated mainly from topsoil erosions in catchments of the Yangtze River. Correlations of TN content with C/N ratio, POC content with TIC content and POC content with δ^13C values for the cores suggest that turnover degrees of SOM from the salt marsh are overall low, and trends of SOM turnover are clear from the bare flat to the high tidal flat. Bare flat samples show characteristics of original sediments, with minor SOM turnover. Turnover processes of SOM have occurred and are discernable in the high and middle tidal flats, and the mixing degrees of SOM compartments with different turnover rates increase with evolution of the muddy tidal flat. The exclusive strata structure of alternate muddy laminae and silty laminae originated from dynamic depositional processes on muddy tidal flat was a great obstacle to vertical migration of dissolved materials, and SOM turnover was then constrained. The muddy tidal flat processes exerted direct influences on sequestration and turnover of SOM in the salt marsh, and had great constraints on the spatial and temporal characteristics of SOM turnover of the Chongmingdongtan Salt Marsh in the Yangtze River estuary. 展开更多
关键词 salt marsh soil organic carbon carbon cycling soil organic matter turnover the Yangtze River estuary
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A cross-sectional study on nurse turnover intention and influencing factors in Jiangsu Province, China 被引量:16
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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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Pool Sizes and Turnover of Soil Organic Carbon of Farmland Soil in Karst Area of Guilin 被引量:3
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作者 YANG Hui CAO Jianhua +2 位作者 ZHANG Liankai HOU Yanlin MAO Lifeng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第1期39-45,共7页
The three-pool and first-order model separates the mineralizable organic carbon into active,slow,and passive carbon pools.This paper used the model and decomposition curves of the soil organic carbon to fit the active... The three-pool and first-order model separates the mineralizable organic carbon into active,slow,and passive carbon pools.This paper used the model and decomposition curves of the soil organic carbon to fit the active pool and its decomposition rate,slow pool and its decomposition rate.The results showed that the size of the active pool from different profiles accounted for 2.09%-3.08% of the total soil organic carbon and the mean residue time was 3.57-17.21 days.And the size of the slow pool accounted for 3.19%-43.55% and the mean residue time was 1.12-4.94 years.Acid hydrolysis(6M HCl) was used to fractionate the passive organic carbon,which accounted for 50.83%-94.44% of the total soil organic carbon. 展开更多
关键词 karst area FARMLAND soil organic carbon pool turnover time
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An experimental analysis on the turnover time of railway freight transportation based on the impact strength of factors 被引量:4
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作者 张光远 DING Xiao-dong +1 位作者 鲁工圆 于洋 《Journal of Chongqing University》 CAS 2017年第3期113-123,共11页
Based on the factors impact strength model(FISM), we studied on calculation formulas of influence strength and key elements of FISM, and analyzed the turnover time of railway freight transportation of China. The resul... Based on the factors impact strength model(FISM), we studied on calculation formulas of influence strength and key elements of FISM, and analyzed the turnover time of railway freight transportation of China. The results show that wagon transfer time is the most critical factor among the three subjective factors of wagons turnover time. The FISM based analysis of wagon transfer time show that the wagon turnover time is significantly correlated with transit time with resorting. Among the seven factors of detention time of transit time with resorting, the time of waiting to departing, converging, and waiting to break-up are key factors, while the time of make-up, break-up, arrival and departure are general factors. We carried out one empirical research based on the data of Baoji East Railway Station in 2015. The results of empirical research and FISM are consistent completely. 展开更多
关键词 railway transportation wagon turnover time impact strength wagon transfer time correlation coefficient method
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The impact of work support and organizational career growth on nurse turnover intention in China 被引量:11
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作者 Yang Yang Yan-Hui Liu +1 位作者 Jing-Ying Liu Hong-Fu Zhang 《International Journal of Nursing Sciences》 2015年第2期134-139,共6页
Objective:The paper aimed to explore the impact of work support and potential for career advancement on the nurse turnover intention in order to find an effective approach to curb high turnover.Methods:A cross-section... Objective:The paper aimed to explore the impact of work support and potential for career advancement on the nurse turnover intention in order to find an effective approach to curb high turnover.Methods:A cross-sectional survey of 526 nurses from eight teaching hospitals in Tianjin,China,was conducted to test the hypothesized multilevel model.The organizational career growth scale,work support scale,and the nurse turnover intention scale were used to measure the effect of organizational career growth and work support on nurse turnover intention.Finally,SPSS 17.0 and AMOS 17.0 software were used to analyse the relationship of these variables.Results:The score of the three scales nurse turnover,organizational career growth,and work support were 1.98±0.60,2.40±0.50,and 4.06±0.98,respectively.The total and direct effects of work support on turnover intention were0.361(p<0.01)and0.147(p<0.01),respectively.The indirect effect was0.169 with a 95%bootstrap confidence interval of0.257 to0.102.Conclusion:The study showed a lack of work support negatively and directly associated with nurse turnover intention.Additional opportunities for career growth within the organization may strengthen the effect of work support and consequently increase the retention of qualified nursing staff. 展开更多
关键词 NURSE Organizational career growth turnover intention Work support
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Deformation early-warning index for heightened gravity dam during impoundment period 被引量:9
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作者 Bo Chen Zi-shen Huang +1 位作者 Teng-fei Bao Zheng Zhu 《Water Science and Engineering》 EI CAS CSCD 2021年第1期54-64,共11页
The mechanical parameters of materials in a dam body and dam foundation tend to change when dams are reinforced in aging processes.It is important to use an early-warning index to reflect the safety status of dams,par... The mechanical parameters of materials in a dam body and dam foundation tend to change when dams are reinforced in aging processes.It is important to use an early-warning index to reflect the safety status of dams,particularly of heightened projects in the impoundment period.Herein,a new method for monitoring the safety status of heightened dams is proposed based on the deformation monitoring data of a dam structure,a statistical model,and finite-element numerical simulation.First,a fast optimization inversion method for estimation of dam mechanical parameters was developed,which used the water pressure component extracted from a statistical model,an improved inversion objective function,and a genetic optimization iterative algorithm.Then,a finite element model of a heightened concrete gravity dam was established,and the deformation behavior of the dam with rising water levels in the impoundment period was simulated.Subsequently,mechanical parameters of aged dam parts were calculated using the fast optimization inversion method with simulated deformation and the water pressure deformation component obtained by the statistical model under the same conditions of water pressure change.Finally,a new earlywarning index of dam deformation was constructed by means of the forward-simulated deformation and other components of the statistical model.The early-warning index is useful for forecasting dam deformation under different water levels,especially high water levels. 展开更多
关键词 Concrete gravity dam Parameter inverse analysis Structural health monitoring early-warning index Finite element simulation
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Assessment of bone turnover and bone quality in type 2 diabetic bone disease: current concepts and future directions 被引量:10
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作者 Mishaela R Rubin Janina M Patsch 《Bone Research》 SCIE CAS CSCD 2016年第1期1-9,共9页
Substantial evidence exists that in addition to the well-known complications of diabetes, increased fracture risk is an important morbidity. This risk is probably due to altered bone properties in diabetes. Circulatin... Substantial evidence exists that in addition to the well-known complications of diabetes, increased fracture risk is an important morbidity. This risk is probably due to altered bone properties in diabetes. Circulating biochemical markers of bone turnover have been found to be decreased in type 2 diabetes (T2D) and may be predictive of fractures independently of bone mineral density (BMD). Serum sclerostin levels have been found to be increased in T2D and appear to be predictive of fracture risk independent of BMD. Bone imaging technologies, including trabecular bone score (TBS) and quantitative CT testing have revealed differences in diabetic bone as compared to non-diabetic individuals. Specifically, high resolution peripheral quantitative CT (HRpQCT) imaging has demonstrated increased cortical porosity in diabetic postmenopausal women. Other factors such as bone marrow fat saturation and advanced glycation endproduct (AGE) accumulation might also relate to bone cell function and fracture risk in diabetes. These data have increased our understanding of how T2D adversely impacts both bone metabolism and fracture risk. 展开更多
关键词 BONE Assessment of bone turnover and bone quality in type 2 diabetic bone disease TYPE
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Job burnout and turnover intention among nurses in China:the mediating effects of positive emotion 被引量:1
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作者 Li-Feng Yang Jing-Ying Liu Yan-Hui Liu 《Frontiers of Nursing》 CAS 2018年第1期43-47,共5页
Objective: The aim of this study was to explore whether positive emotion mediates the relationship between job burnout and turnover intentions among Chinese nurses.Methods: A cross-sectional survey was conducted in th... Objective: The aim of this study was to explore whether positive emotion mediates the relationship between job burnout and turnover intentions among Chinese nurses.Methods: A cross-sectional survey was conducted in the present study. Full-time registered nurses(n = 150) from Grade A hospitals in Tianjin were surveyed. Pearson correlation, hierarchical regression analyses, and the Sobel test were used in the study.Results: The results illustrated that positive emotion mediated the relationship between burnout and nurses' turnover intention.Conclusions: Nursing administrators should pay more attention to the benefits of positive emotions on working motivation.It is helpful to relieve burnout in the working process so that nurses are willing to remain in their current employment. 展开更多
关键词 POSITIVE EMOTION BURNOUT turnover intentions
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Correlation of Serum Leptin Level with Bone Mineral Density and Bone Turnover Markers in Chinese Adolescent Dancers 被引量:1
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作者 LI-CHEN YANG YAN LAN +3 位作者 JING HU YAN-HUA YANG QIAN ZHANG JIAN-HUA PIAO 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第5期369-373,共5页
Objective To investigate plasma leptin concentrations in adolescent female dancers and to determine whether leptin has some effects on their bone mineral density (BMD) and bone turnover markers. Methods Sixty dancer... Objective To investigate plasma leptin concentrations in adolescent female dancers and to determine whether leptin has some effects on their bone mineral density (BMD) and bone turnover markers. Methods Sixty dancers aged 15-17 years and 77 healthy controls were enrolled in the study. Bone mineral density (BMD) and body composition were detected by dual energy X-ray absorptiometry. Serum leptin concentrations were measured by radioimmunoassay (RIA). Two bone turnover markers, bone-specific alkaline phosphatase (BAP) and tartrate-resistant acid phosphatase(TRACP), were determined by ELISA. Results The dancers had a lower fat mass and a lower leptin level than the controls, while they had a relatively higher BMD of the total body and legs after adjustment for BMI and age. The levels of bone resorption and formation of markers were higher in the dancers than in the controls. Leptin was positively correlated with BMI, body weight, fat mass, and percentage of body fat. In dancers, Leptin was positively correlated with the BMD of the total body and the left leg. However, after adjustment for BMI, no correlation of serum leptin concentrations with BMD values was found in either dancers or controls. Nor correlation was found between leptin and bone turnover markers after adjustment for BMI. Conelusion The leptin profile is different between the controls and the dancers with a lower BMI and a lower fat mass. Circulating plasma leptin level depends on BMI and is not a direct determinant of BMD in Chinese adolescent dancers. 展开更多
关键词 LEPTIN Bone mineral density Bone turnover marker Adolescent dancer China
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Abusive supervision and turnover intention: Mediating effects of psychological empowerment of nurses 被引量:4
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作者 Dongmei Lyu Lingling Ji +2 位作者 Qiulan Zheng Bo Yu Yuying Fan 《International Journal of Nursing Sciences》 CSCD 2019年第2期198-203,共6页
Objective: This study aims to determine the mediating effects of psychological empowerment on abusive supervision and turnover intention as perceived by nurses to provide information to change the status of nurse turn... Objective: This study aims to determine the mediating effects of psychological empowerment on abusive supervision and turnover intention as perceived by nurses to provide information to change the status of nurse turnover.Methods: A cross-sectional survey (a questionnaire examining perceptions of abusive supervision,measurement of psychological empowerment,and questionnaire for turnover intention) was used to collect data.A total of 1127 clinical nurses,who were recruited through convenience sampling,participated in the survey.Results: Nurses' average perceived abusive supervision,psychological empowerment,and turnover intention scores were 1.62 ± 0.95,3.24 ± 0.83,and 14.17 ± 3.78,respectively.Psychological empowerment was found to mediate the relationship between abusive supervision and turnover intention (P< 0.01).Turnover intention tends to be stronger and psychological empowerment reduced when nurse managers adopt an abusive leadership style.Conclusions: Nurses' psychological empowerment is an intermediary variable that predicts the relationship between abusive supervision and turnover intention.Nurse managers should manage abusive supervision to increase nurses' psychological empowerment and decrease turnover intention. 展开更多
关键词 Abusive supervision Nurse administrators PERCEPTION Psychological empowerment Surveys and questionnaires turnover intention
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Reduced turnover rate of topsoil organic carbon in old-growth forests:a case study in subtropical China 被引量:5
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作者 Xin Xiong Juxiu Liu +5 位作者 Guoyi Zhou Qi Deng Huiling Zhang Guowei Chu Ze Meng Deqiang Zhang 《Forest Ecosystems》 SCIE CSCD 2021年第4期778-788,共11页
Background:Old-growth forests are irreplaceable with respect to climate change mitigation and have considerable carbon(C)sink potential in soils.However,the relationship between the soil organic carbon(SOC)turnover ra... Background:Old-growth forests are irreplaceable with respect to climate change mitigation and have considerable carbon(C)sink potential in soils.However,the relationship between the soil organic carbon(SOC)turnover rate and forest development is poorly understood,which hinders our ability to assess the C sequestration capacity of soil in old-growth forests.Methods:In this study,we evaluated the SOC turnover rate by calculating the isotopic enrichment factor β(defined as the slope of the regression between ^(13)C natural abundance and log-transformed C concentrations)along 0-30 cm soil profiles in three successional forests in subtropical China.A lower β(steeper slope)is associated with a higher turnover rate.The three forests were a 60-year-old P.massoniana forest(PF),a 100-year-old coniferous and broadleaved mixed forest(MF),and a 400-year-old monsoon evergreen broadleaved forest(BF).We also analyzed the soil physicochemical properties in these forests to examine the dynamics of SOC turnover during forest succession and the main regulators.Results:The β value for the upper 30-cm soils in the BF was significantly(p<0.05)higher than that in the PF,in addition to the SOC stock,although there were nonsignificant differences between the BF and MF.The β value was significantly(p<0.05)positively correlated with the soil recalcitrance index,total nitrogen,and available nitrogen contents but was significantly(p<0.01)negatively correlated with soil pH.Conclusions:Our results demonstrate that SOC has lower turnover rates in old-growth forests,accompanied by higher soil chemical recalcitrance,nitrogen status,and lower soil pH.This finding helps to elucidate the mechanism underlying C sequestration in old-growth forest soils,and emphasizes the important value of old-growth forests among global C sinks. 展开更多
关键词 Forest succession Old-growth forests Soil organic carbon turnover rate 13C natural abundance
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A new early-warning prediction system for monitoring shear force of fault plane in the active fault 被引量:2
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作者 Manchao He Yu Wang Zhigang Tao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2010年第3期223-231,共9页
The most common method used to describe earthquake activity is based on the changes in physical parameters of the earth's surface such as displacement of active fault and seismic wave.However,such approach is not suc... The most common method used to describe earthquake activity is based on the changes in physical parameters of the earth's surface such as displacement of active fault and seismic wave.However,such approach is not successful in forecasting the movement behaviors of faults.In the present study,a new mechanical model of fault activity,considering the shear strength on the fault plane and the influence of the resistance force,is established based on the occurrence condition of earthquake.A remote real-time monitoring system is correspondingly developed to obtain the changes in mechanical components within fault.Taking into consideration the local geological conditions and the history of fault activity in Zhangjiakou of China,an active fault exposed in the region of Zhangjiakou is selected to be directly monitored by the real-time monitoring technique.A thorough investigation on local fault structures results in the selection of two suitable sites for monitoring potential active tectonic movements of Zhangjiakou fault.Two monitoring curves of shear strength,recorded during a monitoring period of 6 months,turn out to be steady,which indicates that the potential seismic activities hardly occur in the adjacent region in the near future.This monitoring technique can be used for early-warning prediction of the movement of active fault,and can help to further gain an insight into the interaction between fault activity and relevant mechanisms. 展开更多
关键词 active faults monitoring EARTHQUAKE early-warning system shear strength
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Risk Early-Warning Method for Natural Disasters Based on Integration of Entropy and DEA Model 被引量:4
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作者 Fengshan Wang Yan Cao Meng Liu 《Applied Mathematics》 2011年第1期23-32,共10页
Risk early-warning of natural disasters is a very intricate non-deterministic prediction, and it was difficult to resolve the conflicts and incompatibility of the risk structure. Risk early-warning factors of natural ... Risk early-warning of natural disasters is a very intricate non-deterministic prediction, and it was difficult to resolve the conflicts and incompatibility of the risk structure. Risk early-warning factors of natural disasters were differentiated into essential attributes and external characters, and its workflow mode was established on risk early-warning structure with integrated Entropy and DEA model, whose steps were put forward. On the basis of standard risk early-warning DEA model of natural disasters, weight coefficient of risk early-warning factors was determined with Information Entropy method, which improved standard risk early-warning DEA model with non-Archimedean infinitesimal, and established risk early-warning preference DEA model based on integrated entropy weight and DEA Model. Finally, model was applied into landslide risk early-warning case in earthquake-damaged emergency process on slope engineering, which exemplified the outcome could reflect more risk information than the method of standard DEA model, and reflected the rationality, feasibility, and impersonality, revealing its better ability on comprehensive safety and structure risk. 展开更多
关键词 ENTROPY Data Envelopment Analysis Comprehensive INTEGRATION ESSENTIAL ATTRIBUTE Risk early-warning Natural DISASTER
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