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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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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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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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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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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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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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Factors Affecting Nurses’ Turnover in Alhassa Governmental Hospitals
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作者 Noora Yousef Al Soqair 《Open Journal of Nursing》 2021年第11期960-980,共21页
Nurse turnover can negatively impact delivering patient care in the health facilities which will affect the patient’s health and reduce the quality of care. The MOH faces a serious challenge or high nursing staff tur... Nurse turnover can negatively impact delivering patient care in the health facilities which will affect the patient’s health and reduce the quality of care. The MOH faces a serious challenge or high nursing staff turnover and the intention to leave the workforce. <strong>Aim:</strong> To explore one of the significant human recourse problems in the MOH and affecting the healthcare system, which is, factors affecting nurses’ turnover in governmental hospitals using Alhassa governmental hospitals as a case study.<strong> Method:</strong> A quantitative research method used to explore the factors affecting nurses’ turnover in the governmental hospitals in Alhassa. <strong>Result:</strong> According to the study finding, management style was a factor more likely to indicate nurses’ turnover. It defines the impact of management style and works environment on nurses’ and clients’ systems. Individual factors were the second influence on their turnover. The balance between nurses’ work and their family need was the first issue that had affected their work. Organization factors are also an influence on the nurses’ turnover in Alhassa region. <strong>Conclusion: </strong>Nurses’ turnover is a significant issue in a human resource in MOH. This study first applied in Alhassa region that highlighted the factors that affect nurses’ turnover. Nurses’ turnover is a continuous problem that occurs in the health facilities related to management method causes, personal causes or organizational causes. Management style was the most influences on nurses’ turnover in this study changing or modifying management style that can intent nurses to continue their work in the hospital in Alhassa region. 展开更多
关键词 Nurse turnover turnover in Healthcare Management Style Individual Factors Organization Factors Work Environment turnover
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The Impact of Turnover Ratios on Jordanian Services Sectors' Performance
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作者 Lina Warrad Rania AlOmari 《Journal of Modern Accounting and Auditing》 2015年第2期77-85,共9页
Profitability ratios are a group of financial ratios that indicate how much profit a business is earning within a certain context, while asset utilization ratios indicate how efficient a business is in operating its a... Profitability ratios are a group of financial ratios that indicate how much profit a business is earning within a certain context, while asset utilization ratios indicate how efficient a business is in operating its assets to generate cash. The difference between profitability ratios and turnover ratios is the fact that turnovers are more specific. While profitability ratios measure overall performance in terms of profits, asset utilization ratios focus on specific measurements within the business) We conduct this study to verify the impact of turnover ratios on Jordanian services sectors' performance during the period from 2009 to 2012. The study showed that there is no significant impact of turnover ratios on Jordanian services sectors' profitability, and by testing the main and sub hypotheses, the study revealed that there is no significant impact of turnover ratios on Jordanian services sectors' return on assets (ROA), there is no significant impact of working capital turnover on Jordanian services sectors' ROA, there is no significant impact of total asset turnover on Jordanian services sectors' ROA, and there is no significant impact of fixed asset turnover on Jordanian services sectors' ROA. Also, the study showed that there is no significant impact of turnover ratios on Jordanian services sectors' return on equity (ROE), there is no significant impact of working capital turnover on Jordanian services sectors' ROE, there is no significant impact of total asset turnover on Jordanian services sectors' ROE, and there is no significant impact of fixed asset turnover on Jordanian services sectors' ROE. Moreover, the study concluded that the educational services sector has the lowest working capital turnover and healthcare services sector has the highest. In addition, we find that the hotels and tourism sector has the lowest total asset turnover ratio, while the utilities and energy sector has the highest and that the hotels and tourism sector has the lowest fixed asset turnover, while the utilities and energy sector has the highest. The transportation sector has the lowest ROA and technology and communication sector has the highest. Finally, we find that transportation sector has the lowest ROE and the technology and communication sector has the highest. 展开更多
关键词 working capital turnover total asset tumover fixed asset turnover return on assets (ROA) retum on equity (ROE) Amman Stock Exchange (ASE)
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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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Effects of Soil Texture and CaCO_3 on Turnover of Organic Material in Chao Soils 被引量:10
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作者 SUNBO LINXIN-XIONG 《Pedosphere》 SCIE CAS CSCD 1993年第2期133-144,共12页
Decomposition experiments of 14C-labelled sickle alfalfa in chao soils of different texture and these soils after removal of CaCO3 were carried out under field and laboratory conditions respectively. The amount of res... Decomposition experiments of 14C-labelled sickle alfalfa in chao soils of different texture and these soils after removal of CaCO3 were carried out under field and laboratory conditions respectively. The amount of residual 14C in, or 14CO2 evolved from, the soils at intervals after the beginning of decomposition were measured and the distribution of native and labelled C between particle size fractions isolated from these soils was edtermined. Results showed that contents of both labelled (14C) and non-labelled (12C) carbon decreased with increasing particle size. The enrichment factor for 14C was higher than that for 12C in the clay fraction, the reverse being true for the silt enrichment factors. The effect of soil texture on the decomposition of plant material could not be observed in chao soils when the clay content was lower than 270g kg-1, while it became obvious once CaCO3 was removed from these soils. The decomposition rate of plant material in the soil from which the native CaCO3 was removed was correlated significantly to both the clay content of the soil and the application rate of CaCO3. A preliminary correction equation describing the effect of clay and CaCO3 on the decomposition of organic material in chao soil was derived from the results obtained. 展开更多
关键词 CaCO_3 CLAY (14)~C labelled sickle alfalfa turnover
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The impact of work support and organizational career growth on nurse turnover intention in China 被引量:12
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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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Assessment of bone turnover and bone quality in type 2 diabetic bone disease: current concepts and future directions 被引量:12
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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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Variation patterns of fine root biomass, production and turnover in Chinese forests 被引量:6
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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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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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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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Clinical benefits of biochemical markers of bone turnover in Egyptian children with chronic liver diseases 被引量:3
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作者 Karam A Mahdy Hanaa H Ahmed +1 位作者 Fathia Mannaa Azza Abdel-Shaheed 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第5期785-790,共6页
AIM: To investigate the association between serum insulin-like growth factor 1 (IGF-1), osteocalcin, and parathyroid hormone (PTH) levels with the etiology and clinical condition of patients with chronic liver di... AIM: To investigate the association between serum insulin-like growth factor 1 (IGF-1), osteocalcin, and parathyroid hormone (PTH) levels with the etiology and clinical condition of patients with chronic liver disease. METHODS: Eighty children with hepatocellular damage were divided into 3 groups according to the etiology of disease infection: bilharziasis (9 patients), hepatitis B virus (HBV, 12 patients) and hepatitis C virus (HCV, 29 patients). The Child score index was found as A in 24 patients, B in 22 patients, C in 4 patients. Thirty healthy children served as control group.HBsAg, HBcAbIgM, HBcAbIgG, and anti-HCV were detected using ELISA technique. HCV-RNA was measured by reverse transcription polymerase chain reaction (RT-PCR). Antibllharzial antibodies were detected by indirect haemagglutination test. Liver function tests were performed using autoanalyser. Serum IGF-1, osteocalcin and PTH levels were measured by ELISA technique. Abdominal ultrasonography was also conducted. RESULTS: Serum IGF-1 level was significantly lower in all patient groups with liver diseases, while serum osteocalcin and PTH levels were significantly elevated in patients with HBV and HCV infections compared with the control group. Serum osteocalcin and PTH concentrations were measured with the severity of liver disease from Child A to C. Child A patients unexpectedly showed significantly reduced IGF-1 levels in comparison to patients staged as Child B or C. Serum osteocalcin level was negatively correlated with albumin (14.7 ± 0.54 vs 3.6 ± 0.10, P 〈 0.05), while that for PTH was positively correlated with total protein (70.1 ± 2.17 vs 6.7 ± 0.10, P 〈 0.05) in patients with HCV infection. 展开更多
关键词 Liver disease Bone turnover Insulin-like growth factor-1 OSTEOCALCIN Parathyroid hormone
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Organizational commitment and turnover intention among rural nurses in the Philippines: Implications for nursing management 被引量:3
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作者 Leodoro J.Labrague Denise M.McEnroe-Petitte +3 位作者 Konstantinos Tsaras Jonas P.Cruz Paolo C.Colet Donna S.Gloe 《International Journal of Nursing Sciences》 2018年第4期403-408,共6页
Objectives:The unrelenting migration trend of Filipino nurses to other countries has threatened the quality of patient care services in the country.This study explored the extent of nurses'organizational commitmen... Objectives:The unrelenting migration trend of Filipino nurses to other countries has threatened the quality of patient care services in the country.This study explored the extent of nurses'organizational commitment and turnover intention in the Philippines.Furthermore,predictors of nurses'organizational commitment and turnover intention were identified.Methods:A cross-sectional research design was adopted for this study.Two hundred nurses from nine rural hospitals in the Central Philippines were asked to participate in the study and 166 nurses responded(an 83%response rate).Two standardized instruments were used:the Organizational Commitment Questionnaire and the Six-item Turnover Intention Inventory Scale.Results:Findings revealed that Philippine nurses were moderately committed(3.13±0.24)to and were undecided(2.42±0.67)whether or not to leave their organization.Nurses'age(P=0.006),gender,(t=-2.25,P=0.026),education(t=2.38,P<0.001),rank(t=4.38,P<0.001),and work experience(t=2.18,P=0.031)correlated significantly with organizational commitment,while nurses'age(P=0.028)and education(t=1.99,P=0.048)correlated significantly with turnover intention.An inverse relationship was identified between the organizational commitment and turnover intention(r=-0.22,P=0.005).Conclusion:The findings of this study highlight the need for formulation and implementation of interventions to promote life-long commitment in nurses and to reduce turnover rates. 展开更多
关键词 Hospitals RURAL Nurses Organizational commitment Philippines turnover intention
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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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Estimation of Turnover and Equilibrium of Soil Organic Matter Using a Mathematical Approach 被引量:2
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作者 WU Chun-Yan CHEN Yi WANG Jia-Yu WANG Sheng-Jia 《Pedosphere》 SCIE CAS CSCD 2006年第5期634-645,共12页
The methods based on N uptake of aerial-plants, soil organic matter (SOM) dynamics, Jenny's equation, and actual measurement of long-term field experiments in Jiaxing, Quzhou, Huangyan and Hangzhou of Zhejiang Pro... The methods based on N uptake of aerial-plants, soil organic matter (SOM) dynamics, Jenny's equation, and actual measurement of long-term field experiments in Jiaxing, Quzhou, Huangyan and Hangzhou of Zhejiang Province, China were used to determine the organic mineralization rate being helpful in estimating the organic requirement for SOM equilibrium. The results showed that the estimated mineralization ratios of SOM for Jiaxing and Quzhou were, respectively, 0.0404 and 0.0508 based on N uptake of aerial-plants in non-fertilized plots; 0.0405 and 0.012 using SOM dynamics in non-fertilized plots; and 0.0413 and 0.0513 using the actual investigated data and Jenny's equation. With Jenny's equation, soil organic C balance in manure + N-P-K plots was estimated at nearly 28.8 g kg-1 for Jiaxing and 32.4 g kg-1 for Quzhou with predicted SOM linearly related to the actual investigated values (r2 = 0.9640 for Jiaxing and 0.8541 for Quzhou). To maintain the SOM balance in the non-fertilized plots the recommended rate of organic materials was 3 000-6 600 kg ha-1, and the relevant rates of farm yard manure (FYM) in the manure and N-P-K plots were estimated at 3 375 (dry) and 17670 kg ha-1 (wet) for Jiaxing, 1845 (dry) and 6090 kg ha-1 (wet) for Quzhou. 展开更多
关键词 EQUILIBRIUM mathematic modeling rice fields soil organic matter (SOM) turnover
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