Inland culture of shrimp integrated with irrigation could be one of the most feasible livelihood options for many households nearby saline land.Compared with seawater and most of reported brackish water used for shrim...Inland culture of shrimp integrated with irrigation could be one of the most feasible livelihood options for many households nearby saline land.Compared with seawater and most of reported brackish water used for shrimp culture,the sulfate content was higher in both surface and ground water in the central Asia.We evaluated the effects of salinity,the SO_(4)^(2-)/Cl^(-)ratio and their interaction on the growth,oxygen consumption,Na+/K+-ATPase activity,total antioxidant capacity(T-AOC),and hepatopancreas histology of Litopenaeus vannamei reared in artificial seawater.The experiment lasted for 30 d,two salinity levels(20 and 10)and four SO_(4)^(2-)/Cl^(-)ratios(0.14,0.577,1.127,and 2.225 mg/mg)of waters were set.Results show no significant differences in survival among groups.Salinity and its interaction effects with SO_(4)^(2-)/Cl^(-)ratio did not significantly affect the final body weight,weight gain,and specific growth rate of shrimps,whereas the SO_(4)^(2-)/Cl^(-)ratio did(P<0.05).Shrimp mean weight gain and specific growth rate at water SO_(4)^(2-)/Cl^(-)ratio of 2.225 were significantly lower than at ratio of 0.14.At salinity 20,the shrimp final body weight at water SO_(4)^(2-)/Cl^(-)ratio of 2.225 was significantly lower than at other ratios(P<0.05),whereas there was no significant difference in final body weight among treatments at salinity 10(P>0.05).Oxygen consumption,Na^(+)/K^(+)-ATPase activity,and T-AOC increased with increasing SO_(4)^(2-)/Cl^(-)ratio at both salinities.L.vannamei exposed to water SO_(4)^(2-)/Cl^(-)ratio of 2.225 at salinity 20 showed severe histopathological changes.This study indicated that L.vannamei has strong tolerance to sulfate in brackish water environment.The shrimp is more adaptable to SO_(4)^(2-)/Cl^(-)ratios below 2.225 at lower salinity,and the optimal SO_(4)^(2-)/Cl^(-)range for the growth is 0.14–0.577(mg/mg)regardless of salinity level.展开更多
In order to further ensure that the 2030 Agenda for Sustainable Development is to be implemented and the action measures of all countries are consistent, the United Nations has put forward a set of indicators to monit...In order to further ensure that the 2030 Agenda for Sustainable Development is to be implemented and the action measures of all countries are consistent, the United Nations has put forward a set of indicators to monitor and evaluate the progress of global sustainable development. This set of evaluation indicators is aimed for global and regional progress. An important feature of the evaluation indicators is that they are internationally comparable, but due to the large differences in the levels of sustainable development among countries, this framework of evaluation indicators has a disadvantage that it does not apply to tracking the progress of sustainable development at the national level. This paper focuses on the analysis of specific issues in the application of the global sustainable development indicators framework to meet the goals and targets of the UN and builds a system of evaluation indicators to assess the progress of sustainable development at the national level in China, and offers a perspective to assess China’s progress as well.展开更多
In this study,we evaluate the forecast skill of the subseasonal-to-seasonal(S2S)prediction model of the Beijing Climate Center(BCC)for the boreal summer intraseasonal oscillation(BSISO).We also discuss the key factors...In this study,we evaluate the forecast skill of the subseasonal-to-seasonal(S2S)prediction model of the Beijing Climate Center(BCC)for the boreal summer intraseasonal oscillation(BSISO).We also discuss the key factors that inhibit the BSISO forecast skill in this model.Based on the bivariate anomaly correlation coefficient(ACC)of the BSISO index,defined by the first two EOF modes of outgoing longwave radiation and 850-hPa zonal wind anomalies over the Asian monsoon region,we found that the hindcast skill degraded as the lead time increased.The ACC dropped to below 0.5for lead times of 11 days and longer when the predicted BSISO showed weakened strength and insignificant northward propagation.To identify what causes the weakened forecast skill of BSISO at the forecast lead time of 11 days,we diagnosed the main mechanisms responsible for the BSISO northward propagation.The same analysis was also carried out using the observations and the outputs of the four-day forecast lead that successfully predicted the observed northward-propagating BSISO.We found that the lack of northward propagation at the 11-day forecast lead was due to insufficient increases in low-level cyclonic vorticity,moistening and warm temperature anomalies to the north of the convection,which were induced by the interaction between background mean flows and BSISO-related anomalous fields.The BCC S2S model can predict the background monsoon circulations,such as the low-level southerly and the northerly and easterly vertical shears,but has limited capability in forecasting the distributions of circulation and moisture anomalies.展开更多
BACKGROUND： Animal experiments and clinical studies about tissue engineering method applied to repair nerve injury mainly focus on seeking ideal artificial nerve grafts, nerve conduit and seed cells. Autologous nerve...BACKGROUND： Animal experiments and clinical studies about tissue engineering method applied to repair nerve injury mainly focus on seeking ideal artificial nerve grafts, nerve conduit and seed cells. Autologous nerve, allogeneic nerve and xenogeneic nerve are used to bridge nerve defects, it is one of the methods to promote the repair of nerve injury by culturing and growing Schwann cells, which can secrete various neurotrophic factor activities, in the grafts. OBJECTIVE ： To observe the effect of acellular nerve grafts co-cultured with Schwann cells in repairing defects of sciatic nerve. DESIGN： An observational comparative study.SETTING： Tissue Engineering Laboratory of China Medical University.MATERIALS： The experiment was carried out in the Tissue Engineering Laboratory of China Medical University between April 2004 and April 2005. Forty neonatal Sprague-Dawley rats of 5-8 days （either males or females） and 24 male Wistar rats of 180-220 g were provided by the experimental animal center of China Medical University. METHODS： ① Culture of Schwann cells： The bilateral sciatic nerves and branchial plexus were isolated from the 40 neonatal SD rats. The sciatic nerves were enzymatically digested with collagenase and dispase, isolatd, purified and cultured with the method of speed-difference adhersion, and identified with the SABC immunohistochemical method. ② Model establishment： In vitro Schwann cells were microinjected into 10-mm long acellular nerve grafts repairing a surgically created gap in the rat sciatic nerve. According to the different grafted methods, the animals were randomly divided into three groups： autografts （n=8）, acellular nerve grafts （n=8）, or acellular nerve grafts with Schwann cells （n=8）. ③ The regenerated nerve fiber number and average diameter of myeline sheath after culture were statistically anlayzed. MAIN OUTCOME MEASURES： ① The regenerated nerve ultrastructure, total number and density of myelinated nerve fibers, and the thickness of myeline sheath were observed under electron microscope. ② The images were processed with the Mias-1000 imaging analytical system to calculate the number of myelinated nerve fibers, and the thickness of myeline sheath. RESULTS： All the 24 Wistar rats were involved in the analysis of results. ① Results observed under transmission electron microscope： The regenerated myelinated nerve fibers in the group of acellular nerve grafts with Schwann cells were more even than those in the group of acellular nerve grafts, the number of myelinated nerve fibers and thickness of myelin sheath were close to those in the allografts group （P 〉 0.05）, but significantly different from those in the group of acellular nerve grafts （P 〈 0.05）. ② Results observed under scanning electron microscope： A great amount of Schwann cells with two polars were observed in the group of grafts with Schwann cells, the feature of cultured Schwann cells showed shoulder by shoulder, head to head. ③ The number of myelinated nerve fibers and thickness of myelin sheath analyzed by Mias-1000 imaging system in the group of acellular nerve grafts with Schwann cells were close to those in the autografts group （P 〉 0.05）, but significantly different from those in the group of acellular nerve grafts （P 〈 0.05）.CONCLUSION： Host axonal regeneration is significantly increased after implant of acellular nerve grafts. Acellular nerve grafts with Schwann cells offers a novel approach for repairing the gap of nerve defect.展开更多
Service-oriented manufacturing is an emerging innovative development model,and its core is the deep integration of products and services.It has become a hot issue in current research.In order to deeply explore the evo...Service-oriented manufacturing is an emerging innovative development model,and its core is the deep integration of products and services.It has become a hot issue in current research.In order to deeply explore the evolution path of servitization transformation of manufacturing enterprises,ShaanGu Group is taken as a case,and discusses practical application of service-oriented manufacturing model in different development processes of ShaanGu Group.Thus,four stages of transformation of ShaanGu Group through servitization are summarized:specialized after-sales service stage,rental service stage,engineering complete service stage and financial service stage.Through comparative research,it is found that general evolution path of manufacturing enterprises to service transformation is:the primary stage(providing product-oriented product service system)→the intermediate stage(providing application-oriented product service system)→the advanced stage(providing utility-oriented product service system)→the completed stage(providing pure service).On this basis,some suggestions are provided for manufacturing enterprises to integrate productive services in the process of transformation.展开更多
目的:探讨运动锻炼对大学生睡眠质量的干预效果,为相关实践干预提供有力证据,提升大学生的睡眠质量。方法:(1)通过检索中国知网、PubMed、Web of Science等数据库,获取与运动锻炼、大学生及睡眠相关文献,检索时间为1956年1月1日—2024年...目的:探讨运动锻炼对大学生睡眠质量的干预效果,为相关实践干预提供有力证据,提升大学生的睡眠质量。方法:(1)通过检索中国知网、PubMed、Web of Science等数据库,获取与运动锻炼、大学生及睡眠相关文献,检索时间为1956年1月1日—2024年9月22日;(2)采用Cochrane软件对所选文献进行质量评分,判断其是否符合纳入Meta分析的标准;(3)使用Review 5.3软件对运动锻炼干预大学生睡眠质量的相关文献进行质量检验、整体数据分析、亚组分析、敏感性分析和发表偏倚分析。结果:(1)文献特征和风险评估:经过筛选,最终选择出12篇符合纳入标准的高质量文献,总体研究样本数量为687例。Cochrane系统评价体系说明所纳入文献总体质量较高。(2)整体评价:运动锻炼干预大学生睡眠效果的总体效应量SMD=-1.17,95%CI为[-1.64,-0.70],P<0.00001。(3)亚组分析:针对不同运动项目、不同单次运动时间、不同运动频率和不同运动周期对干预大学生睡眠质量的效果进行分析,发现均存在显著的异质性(I2=87%,P<0.00001)。结论:(1)运动锻炼能够有效改善大学生睡眠质量;(2)运动锻炼对大学生睡眠质量的干预效果受到运动项目、单次运动时间、运动频率和运动周期的影响;(3)单次运动46~60 min、3次/周、持续16周的运动锻炼对改善大学生睡眠质量的效果更好。展开更多
基金Supported by the Science and Technology Program of Jungar Banner 2021“Demonstration and Promotion of Shrimp Farming Technology in Saline-alkali Land of Jungar Banner”,Science and Technology Program of Hangjin Banner 2023,Shandong Key Laboratory of Marine Ecological Restoration(No.201917)the Central Public-interest Scientific Institution Basal Research Fund,CAFS(No.2023 TD 58)。
文摘Inland culture of shrimp integrated with irrigation could be one of the most feasible livelihood options for many households nearby saline land.Compared with seawater and most of reported brackish water used for shrimp culture,the sulfate content was higher in both surface and ground water in the central Asia.We evaluated the effects of salinity,the SO_(4)^(2-)/Cl^(-)ratio and their interaction on the growth,oxygen consumption,Na+/K+-ATPase activity,total antioxidant capacity(T-AOC),and hepatopancreas histology of Litopenaeus vannamei reared in artificial seawater.The experiment lasted for 30 d,two salinity levels(20 and 10)and four SO_(4)^(2-)/Cl^(-)ratios(0.14,0.577,1.127,and 2.225 mg/mg)of waters were set.Results show no significant differences in survival among groups.Salinity and its interaction effects with SO_(4)^(2-)/Cl^(-)ratio did not significantly affect the final body weight,weight gain,and specific growth rate of shrimps,whereas the SO_(4)^(2-)/Cl^(-)ratio did(P<0.05).Shrimp mean weight gain and specific growth rate at water SO_(4)^(2-)/Cl^(-)ratio of 2.225 were significantly lower than at ratio of 0.14.At salinity 20,the shrimp final body weight at water SO_(4)^(2-)/Cl^(-)ratio of 2.225 was significantly lower than at other ratios(P<0.05),whereas there was no significant difference in final body weight among treatments at salinity 10(P>0.05).Oxygen consumption,Na^(+)/K^(+)-ATPase activity,and T-AOC increased with increasing SO_(4)^(2-)/Cl^(-)ratio at both salinities.L.vannamei exposed to water SO_(4)^(2-)/Cl^(-)ratio of 2.225 at salinity 20 showed severe histopathological changes.This study indicated that L.vannamei has strong tolerance to sulfate in brackish water environment.The shrimp is more adaptable to SO_(4)^(2-)/Cl^(-)ratios below 2.225 at lower salinity,and the optimal SO_(4)^(2-)/Cl^(-)range for the growth is 0.14–0.577(mg/mg)regardless of salinity level.
文摘In order to further ensure that the 2030 Agenda for Sustainable Development is to be implemented and the action measures of all countries are consistent, the United Nations has put forward a set of indicators to monitor and evaluate the progress of global sustainable development. This set of evaluation indicators is aimed for global and regional progress. An important feature of the evaluation indicators is that they are internationally comparable, but due to the large differences in the levels of sustainable development among countries, this framework of evaluation indicators has a disadvantage that it does not apply to tracking the progress of sustainable development at the national level. This paper focuses on the analysis of specific issues in the application of the global sustainable development indicators framework to meet the goals and targets of the UN and builds a system of evaluation indicators to assess the progress of sustainable development at the national level in China, and offers a perspective to assess China’s progress as well.
基金supported by the National Basic Research Program of China (973 Program) (Grant No.2015CB453200)
文摘In this study,we evaluate the forecast skill of the subseasonal-to-seasonal(S2S)prediction model of the Beijing Climate Center(BCC)for the boreal summer intraseasonal oscillation(BSISO).We also discuss the key factors that inhibit the BSISO forecast skill in this model.Based on the bivariate anomaly correlation coefficient(ACC)of the BSISO index,defined by the first two EOF modes of outgoing longwave radiation and 850-hPa zonal wind anomalies over the Asian monsoon region,we found that the hindcast skill degraded as the lead time increased.The ACC dropped to below 0.5for lead times of 11 days and longer when the predicted BSISO showed weakened strength and insignificant northward propagation.To identify what causes the weakened forecast skill of BSISO at the forecast lead time of 11 days,we diagnosed the main mechanisms responsible for the BSISO northward propagation.The same analysis was also carried out using the observations and the outputs of the four-day forecast lead that successfully predicted the observed northward-propagating BSISO.We found that the lack of northward propagation at the 11-day forecast lead was due to insufficient increases in low-level cyclonic vorticity,moistening and warm temperature anomalies to the north of the convection,which were induced by the interaction between background mean flows and BSISO-related anomalous fields.The BCC S2S model can predict the background monsoon circulations,such as the low-level southerly and the northerly and easterly vertical shears,but has limited capability in forecasting the distributions of circulation and moisture anomalies.
基金the National Natural Science Foundation of China, No. 30070775 a grant from the Scientific Research Foundation of Liaoning Department of Education, No. 2005L5371
文摘BACKGROUND： Animal experiments and clinical studies about tissue engineering method applied to repair nerve injury mainly focus on seeking ideal artificial nerve grafts, nerve conduit and seed cells. Autologous nerve, allogeneic nerve and xenogeneic nerve are used to bridge nerve defects, it is one of the methods to promote the repair of nerve injury by culturing and growing Schwann cells, which can secrete various neurotrophic factor activities, in the grafts. OBJECTIVE ： To observe the effect of acellular nerve grafts co-cultured with Schwann cells in repairing defects of sciatic nerve. DESIGN： An observational comparative study.SETTING： Tissue Engineering Laboratory of China Medical University.MATERIALS： The experiment was carried out in the Tissue Engineering Laboratory of China Medical University between April 2004 and April 2005. Forty neonatal Sprague-Dawley rats of 5-8 days （either males or females） and 24 male Wistar rats of 180-220 g were provided by the experimental animal center of China Medical University. METHODS： ① Culture of Schwann cells： The bilateral sciatic nerves and branchial plexus were isolated from the 40 neonatal SD rats. The sciatic nerves were enzymatically digested with collagenase and dispase, isolatd, purified and cultured with the method of speed-difference adhersion, and identified with the SABC immunohistochemical method. ② Model establishment： In vitro Schwann cells were microinjected into 10-mm long acellular nerve grafts repairing a surgically created gap in the rat sciatic nerve. According to the different grafted methods, the animals were randomly divided into three groups： autografts （n=8）, acellular nerve grafts （n=8）, or acellular nerve grafts with Schwann cells （n=8）. ③ The regenerated nerve fiber number and average diameter of myeline sheath after culture were statistically anlayzed. MAIN OUTCOME MEASURES： ① The regenerated nerve ultrastructure, total number and density of myelinated nerve fibers, and the thickness of myeline sheath were observed under electron microscope. ② The images were processed with the Mias-1000 imaging analytical system to calculate the number of myelinated nerve fibers, and the thickness of myeline sheath. RESULTS： All the 24 Wistar rats were involved in the analysis of results. ① Results observed under transmission electron microscope： The regenerated myelinated nerve fibers in the group of acellular nerve grafts with Schwann cells were more even than those in the group of acellular nerve grafts, the number of myelinated nerve fibers and thickness of myelin sheath were close to those in the allografts group （P 〉 0.05）, but significantly different from those in the group of acellular nerve grafts （P 〈 0.05）. ② Results observed under scanning electron microscope： A great amount of Schwann cells with two polars were observed in the group of grafts with Schwann cells, the feature of cultured Schwann cells showed shoulder by shoulder, head to head. ③ The number of myelinated nerve fibers and thickness of myelin sheath analyzed by Mias-1000 imaging system in the group of acellular nerve grafts with Schwann cells were close to those in the autografts group （P 〉 0.05）, but significantly different from those in the group of acellular nerve grafts （P 〈 0.05）.CONCLUSION： Host axonal regeneration is significantly increased after implant of acellular nerve grafts. Acellular nerve grafts with Schwann cells offers a novel approach for repairing the gap of nerve defect.
基金Western and Frontier Region Project of Humanities and Social Sciences Research of the Ministry of Education(20XJA630001)Research project of Shaanxi Provincial Key Think Tank on Major Theoretical and Practical issues of Philosophy and Social Sciences(2021ZD1011)+2 种基金Research Project on Major Theoretical and Practical Problems in Social Science Circles of Shaanxi Province(2020Z394)Soft Science Project of Xi'an Science and Technology Plan(2019111713RKX001SF005-3)Key Scientific Research Program of Shaanxi Provincial Department of Education(new think tank project)(20JT025).
文摘Service-oriented manufacturing is an emerging innovative development model,and its core is the deep integration of products and services.It has become a hot issue in current research.In order to deeply explore the evolution path of servitization transformation of manufacturing enterprises,ShaanGu Group is taken as a case,and discusses practical application of service-oriented manufacturing model in different development processes of ShaanGu Group.Thus,four stages of transformation of ShaanGu Group through servitization are summarized:specialized after-sales service stage,rental service stage,engineering complete service stage and financial service stage.Through comparative research,it is found that general evolution path of manufacturing enterprises to service transformation is:the primary stage(providing product-oriented product service system)→the intermediate stage(providing application-oriented product service system)→the advanced stage(providing utility-oriented product service system)→the completed stage(providing pure service).On this basis,some suggestions are provided for manufacturing enterprises to integrate productive services in the process of transformation.
文摘目的:探讨运动锻炼对大学生睡眠质量的干预效果,为相关实践干预提供有力证据,提升大学生的睡眠质量。方法:(1)通过检索中国知网、PubMed、Web of Science等数据库,获取与运动锻炼、大学生及睡眠相关文献,检索时间为1956年1月1日—2024年9月22日;(2)采用Cochrane软件对所选文献进行质量评分,判断其是否符合纳入Meta分析的标准;(3)使用Review 5.3软件对运动锻炼干预大学生睡眠质量的相关文献进行质量检验、整体数据分析、亚组分析、敏感性分析和发表偏倚分析。结果:(1)文献特征和风险评估:经过筛选,最终选择出12篇符合纳入标准的高质量文献,总体研究样本数量为687例。Cochrane系统评价体系说明所纳入文献总体质量较高。(2)整体评价:运动锻炼干预大学生睡眠效果的总体效应量SMD=-1.17,95%CI为[-1.64,-0.70],P<0.00001。(3)亚组分析:针对不同运动项目、不同单次运动时间、不同运动频率和不同运动周期对干预大学生睡眠质量的效果进行分析,发现均存在显著的异质性(I2=87%,P<0.00001)。结论:(1)运动锻炼能够有效改善大学生睡眠质量;(2)运动锻炼对大学生睡眠质量的干预效果受到运动项目、单次运动时间、运动频率和运动周期的影响;(3)单次运动46~60 min、3次/周、持续16周的运动锻炼对改善大学生睡眠质量的效果更好。
