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Construction Method for Performance Management Curriculum Content System Based on Knowledge Graph
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作者 Miaomiao Ma Xia Mu 《教育研究前沿(中英文版)》 2024年第3期8-12,共5页
Performance Management is the core course of human resource management major,but its knowledge points lack multi-dimensional correlations.There are problems such as scattered content and unclear system,and it is urgen... Performance Management is the core course of human resource management major,but its knowledge points lack multi-dimensional correlations.There are problems such as scattered content and unclear system,and it is urgent to reconstruct the content system of the course.Knowledge graph technology can integrate massive and scattered information into an organic structure through semantic correlation and reasoning.The application of knowledge graph to education and teaching can promote scientific and personalized teaching evaluation and better realize individualized teaching.This paper systematically combs the knowledge points of Performance Management course and forms a comprehensive knowledge graph.The knowledge point is associated with specific questions to form the problem map of the course,and then the knowledge point is further associated with the ability target to form the ability map of the course.Then,the knowledge point is associated with teaching materials,question bank and expansion resources to form a systematic teaching database,thereby giving the method of building the content system of Performance Management course based on the knowledge map.This research can be further extended to other core management courses to realize the deep integration of knowledge graph and teaching. 展开更多
关键词 Knowledge Graph Construction Method Curriculum content system Performance Management Course
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A Collaborative Broadcast Content Recording System Using Distributed Personal Video Recorders
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作者 Eunsam Kim Choonhwa Lee 《Computers, Materials & Continua》 2025年第2期2555-2581,共27页
Personal video recorders (PVRs) have altered the way users consume television (TV) content by allowing users to record programs and watch them at their convenience, overcoming the constraints of live broadcasting. How... Personal video recorders (PVRs) have altered the way users consume television (TV) content by allowing users to record programs and watch them at their convenience, overcoming the constraints of live broadcasting. However, standalone PVRs are limited by their individual storage capacities, restricting the number of programs they can store. While online catch-up TV services such as Hulu and Netflix mitigate this limitation by offering on-demand access to broadcast programs shortly after their initial broadcast, they require substantial storage and network resources, leading to significant infrastructural costs for service providers. To address these challenges, we propose a collaborative TV content recording system that leverages distributed PVRs, combining their storage into a virtual shared pool without additional costs. Our system aims to support all concurrent playback requests without service interruption while ensuring program availability comparable to that of local devices. The main contributions of our proposed system are fourfold. First, by sharing storage and upload bandwidth among PVRs, our system significantly expands the overall recording capacity and enables simultaneous recording of multiple programs without the physical constraints of standalone devices. Second, by utilizing erasure coding efficiently, our system reduces the storage space required for each program, allowing more programs to be recorded compared to traditional replication. Third, we propose an adaptive redundancy scheme to control the degree of redundancy of each program based on its evolving playback demand, ensuring high-quality playback by providing sufficient bandwidth for popular programs. Finally, we introduce a contribution-based incentive policy that encourages PVRs to actively participate by contributing resources, while discouraging excessive consumption of the combined storage pool. Through extensive experiments, we demonstrate the effectiveness of our proposed collaborative TV program recording system in terms of storage efficiency and performance. 展开更多
关键词 Collaborative recording TV content personal video recorder erasure coding REPLICATION
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Effects of Soil Selenium(Se)Content and Exogenous Se Supplementation on Crop Se Content
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作者 Mengyin LI Xiaotao ZHU +2 位作者 Shaoying LIAN Hanfang LI Jinmin ZHANG 《Agricultural Biotechnology》 2026年第1期39-41,共3页
[Objectives]This study was conducted to investigate the effects of soil selenium(Se)content and exogenous Se supplementation on crop Se levels and provide a theoretical basis for the production of Se-enriched agricult... [Objectives]This study was conducted to investigate the effects of soil selenium(Se)content and exogenous Se supplementation on crop Se levels and provide a theoretical basis for the production of Se-enriched agricultural products.[Methods]Thirty three representative townships in Xiayi County,Ningling County,and Yongcheng City were selected.Soil Se content and its impact on wheat Se level were measured.The effects of exogenous Se supplementation on the Se content of crops including soybean,wheat,peanut,corn,sweet potato,grape,crisp pear and apple were also investigated.[Results]Showed that the soil Se content in 18 townships of Xiayi County ranged from 0.08 to 0.34 mg/kg,and Se-adequate areas,Se-deficient areas and severely Se-deficient areas accounted for 27.78%,66.67%,and 0.055%of the total,respectively.In Ningling County,the soil Se content in 11 townships ranged from 0.13 to 0.23 mg/kg,and among them,Se-adequate areas and Se-deficient areas comprised 18.18%and 81.82%,respectively.In Yongcheng City,the soil Se content in 4 townships ranged from 0.16 to 0.23 mg/kg,and Se-adequate areas and Se-deficient areas constituted 75.00%and 25.00%,respectively.The soil Se content in 33 townships across Xiayi County,Ningling County,and Yongcheng City ranged from 0.07 to 0.34 mg/kg.However,the Se levels in wheat from all 33 townships fail to meet the standard for Se-enriched agricultural products.It indicates that relying solely on soil Se supply is insufficient for crops to achieve the Se level required for Se-enriched agricultural products.Exogenous Se supplementation could effectively increase the Se content in soybean,wheat,peanut,corn,sweet potato,grape,crisp pear,and apple.Among these,soybean,wheat and peanut showed the highest Se levels after supplementation,all exceeding 0.10 mg/kg and meeting the industry standard for Se-enriched agricultural products.[Conclusions]The results of this study indicates that exogenous Se supplementation can serve as a key measure for producing Se-enriched agricultural products. 展开更多
关键词 Exogenous Se SOIL CROP Se content
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Content validation of the Global Adolescent and Child Physical Activity Questionnaire(GAC-PAQ)in low-,middle-,and high-income countries across 6 continents
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作者 Richard Larouche Saulo Neves de Oliveira +45 位作者 Mahdi Rostami Haji Abadi Judy K.Benavides-Castro Olga L.Sarmiento Garazi Angulo Garay Gabriela Argumedo Joseph O.Ashaolu Ameneh Baghestani Jasmin Bhawra Javier Brazo-Sayavera Nutnaree Choonak Christine Delisle Nystrom Seth Evance Zdenek Hamrik Alejandra Jáuregui Piyakrita Kaewpikul Piyawat Katewongsa Anuradha Khadilkar Geoff Kira McPherry Kuntembwe Yang Liu Marie Lof Tom Loney Maria Lundgren Rubina Mandlik Martine Matapo-Kolisko Chidvilas More Tawonga W.Mwase-Vuma Nattaporn Nilwatta Adewale L.Oyeyemi Susan Paudel Nanthawan Pomkai Justin Richards Diego Augusto Santos Silva Melody Smith Narayan Subedi Dyah Anantalia Widyastari Oliver W.A.Wilson SaloméAubert Valerie Carson Rachel C.Colley Dale W.Esliger Nicholas Kuzik Taru Manyanga John J.Reilly Leigh M.Vanderloo Mark S.Tremblay 《Journal of Sport and Health Science》 2026年第2期52-67,共16页
Background:Investigators from low-,middle-,and high-income countries representing 6 continents contributed to the development of the Global Adolescent and Child Physical Activity Questionnaire(GAC-PAQ).The GAC-PAQ is ... Background:Investigators from low-,middle-,and high-income countries representing 6 continents contributed to the development of the Global Adolescent and Child Physical Activity Questionnaire(GAC-PAQ).The GAC-PAQ is designed to assess physical activity(PA)across all key domains(i.e.,school,chores,work/volunteering,transport,free time,outdoor time).It aimed to address multiple gaps in global PA surveillance(e.g.,omission of important PA domains,insufficient cultural adaptation,underrepresentation of rural areas in questionnaire validation studies).The purpose of this study was to assess the content validity of the GAC-PAQ among PA experts,8-to 17-year-olds,and one of their parents/guardians,and to discuss changes made to the questionnaire based on participants'feedback.Methods:Sixty-two experts in PA measurement and/or surveillance from 24 countries completed an online survey that included both closed-and open-ended questions about the content validity of the GAC-PAQ.The proportion of experts who agreed or strongly agreed with the items was calculated.Child-parent/guardian dyads from 15 countries(n=250;10-40 per country)participated in a structured cognitive interview to assess the clarity of the questions and response options,and they were encouraged to provide suggestions to improve clarity and facilitate completion of the questionnaire.Participating countries are:Aotearoa New Zealand,Brazil,Canada,China,Colombia,Czech Republic,India,Malawi,Mexico,Nepal,Nigeria,Spain,Sweden,Thailand,and the United Arab Emirates.Interviews were conducted in 13 different languages and structured by PA domain.Generic images were included to help participants in answering questions about PA intensity.Results:Expert agreement with the items for each domain exceeded 75%,and their qualitative feedback was used to revise the questionnaire before cognitive interviews.In general,participants found the questionnaire to be comprehensive.Adolescents(12-17 years)found it easier than children(8-11 years)to answer the questions.Several children struggled to answer questions about the duration and intensity of activities and/or concepts related to travel modes,active trips,and organized activities.Many parents/guardians were unsure about the frequency,duration,and intensity of their children's or adolescents'PA at school and/or recommended using more culturally relevant and appropriate images.Some participants misunderstood the concept of activities that“make you stronger”(intended to assess resistance activities)and/or struggled to differentiate between work,volunteering,and chores.Conclusion:Participants'feedback was used to develop a revised,simplified,and culturally adapted GAC-PAQ,which will be pilot-tested in all15 countries in an App that will include country-specific images and narration in local languages.Further research is needed to assess the reliability and validity of the revised GAC-PAQ. 展开更多
关键词 Measurement Surveillance content validity Global health Cultural adaptation
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Particle size ratios and ice content effects on rock-ice avalanche propagation and deposition:Flume experiments and DEM simulations
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作者 LUO Xin YANG Qingqing +1 位作者 HUO Zihao QIN Yao 《Journal of Mountain Science》 2026年第1期221-236,共16页
Rock-ice avalanches in cold high-mountain regions pose severe hazards due to their high mobility,yet the quantitative controls of particle-size ratio and ice content remain insufficiently constrained.This study invest... Rock-ice avalanches in cold high-mountain regions pose severe hazards due to their high mobility,yet the quantitative controls of particle-size ratio and ice content remain insufficiently constrained.This study investigates their coupled effects using inclinedflume experiments and Discrete Element Method(DEM)simulations,covering three gravel sizes(2-5 mm,5-7 mm,7-10 mm)and four ice-content levels(0%,20%,40%,60%).Run-out distance,velocity,energy components,flow regime(Savage number),and segregation indexαwere quantified.Increasing ice content significantly enhances mobility,but with diminishing marginal effectiveness.From 0%to 40%ice content,run-out distance increases by 41%-86%,whereas the additional increase from 40%to 60%contributes only 12%-23%.Particle-size ratio strongly governs segregation intensity.Fine-gravel groups reach segregation indices ofα=0.92-0.98,indicating nearly complete upward migration of ice,whereas medium-gravel and coarse-gravel groups exhibit much weaker segregation,stabilizing atα=0.68-0.74 and 0.60-0.69.Savage number analyses reveal marked flow-regime transitions.At 0%ice content,Savage numbers reach 1.0-1.5,indicating a collisional regime.Increasing ice content suppresses collisionality,with Savage numbers decreasing to 0.03-0.07 at 60%ice content,consistent with dense-regime flow.DEM energy analyses confirm this regime shift:for finegravel mixtures,collision energy decreases by 14%,while sliding-friction energy increases by 33%as ice content increases from 0%to 60%,reflecting enhanced overburden effects imposed by upward-segregated ice layers.Medium and coarse mixtures exhibit weaker or opposite energy-shift patterns,demonstrating strong size dependence.Mechanistically,large particle-size contrasts promote strong segregation and form dense basal rock layers that increase basal friction and reduce mobility.When particle sizes are similar or ice content is high,segregation remains limited,allowing ice to mix into the basal layer,thereby reducing basal friction and enhancing mobility.This research quantitatively demonstrates how composition controls particle spatial distribution,flow regime,and energy dissipation,offering new mechanistic insights into the propagation and deposition behaviors of rock-ice avalanches and improving hazard assessment in vulnerable high-mountain regions. 展开更多
关键词 Rock-ice avalanche DEM Flume experiment Ice content Particle size ratio SEGREGATION
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Analysis of Histochemical Localization and Content Influencing Factors of Saponins in Pseudostellaria heterophylla
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作者 Huiqing PAN Yanda ZHANG +3 位作者 Zhenhua WANG Qi ZHAO Zuyun YE Xin WANG 《Medicinal Plant》 2026年第1期5-9,19,共6页
This paper provides a systematic review of the histochemical localization,content characteristics,and influencing factors of saponins in Pseudostellaria heterophylla based on an extensive literature survey.It provides... This paper provides a systematic review of the histochemical localization,content characteristics,and influencing factors of saponins in Pseudostellaria heterophylla based on an extensive literature survey.It provides an in-depth analysis and summary of the effects of biological factors,environmental conditions,agronomic practices,processing methods,and continuous cropping obstacles on the synthesis of P.heterophylla saponins,as well as their underlying mechanisms.Based on identified gaps in the current literature,future research directions and prospects are proposed.The findings of this review offer valuable insights for advancing the understanding of the saponin biosynthesis mechanisms in P.heterophylla and for enhancing its quality. 展开更多
关键词 Pseudostellaria heterophylla SAPONIN Histochemical localization content influencing factors Research progress
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Effects of Different Moisture Content on the Quality Characteristics of Sichuan Sausage during Frozen Storage
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作者 Qi ZHOU Jiamin ZHANG +2 位作者 Lili JI Wei WANG Ting BAI 《Agricultural Biotechnology》 2026年第1期26-35,共10页
Sichuan sausages with moisture contents of 40%,45%,50%,and 60% were stored at-18℃for durations of 0,2,4,6,and 8 weeks to evaluate the effect of moisture content on the quality attributes of Sichuan sausages during fr... Sichuan sausages with moisture contents of 40%,45%,50%,and 60% were stored at-18℃for durations of 0,2,4,6,and 8 weeks to evaluate the effect of moisture content on the quality attributes of Sichuan sausages during frozen storage.Product indicators including pH,colour,thiobarbituric acid reactive substances(TBARS),total volatile basic nitrogen(TVB-N),texture,electronic nose(E-nose)response,and water-holding capacity(thawing and cooking losses)were determined.The results indicated that as storage time increased,water retention in Sichuan sausages with different moisture contents decreased,while the degree of protein and lipid oxidation increased.This led to an increase in pH value,a colour shift from red-bright to grey-brown,and a deterioration in palatability.Among the samples,sausages with 50% moisture content exhibited the lowest thawing and cooking losses,indicating superior water-holding capacity.After 8 weeks of storage,TBARS and TVB-N values for the 50% moisture group were 19.5%and 2.5%lower,respectively,than those of the 40%and 45%moisture groups,indicating a reduced degree of oxidation.Furthermore,Sichuan sausage with 50%moisture content demonstrated an appropriate pH and colour difference,along with excellent texture and flavour,as evidenced by its higher toughness and satisfactory hardness.In conclusion,Sichuan sausage with 50% moisture content demonstrated the highest overall quality under frozen storage conditions. 展开更多
关键词 Sichuan sausage Moisture content Storage time Quality characteristics
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Impact of heatwave and thinning on tree growth and soil water content in young lodgepole pine forests
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作者 Yiping Hou Xiaohua Wei +4 位作者 Zhipeng Xu Sheena A.Spencer Ming Qiu Shixuan Lyu Wenfei Liu 《Forest Ecosystems》 2026年第1期83-94,共12页
Extreme climate events(e.g.,heatwaves and droughts)are becoming increasingly frequent due to global climate change,which inevitably affects tree growth and various other ecological processes.While the impacts of droug... Extreme climate events(e.g.,heatwaves and droughts)are becoming increasingly frequent due to global climate change,which inevitably affects tree growth and various other ecological processes.While the impacts of droughts on these processes have been widely evaluated,the effects of heatwaves on tree growth and soil water content(SWC)remain poorly understood,particularly those related to thinning treatment.In this study,we evaluated the impacts of the 2021 Pacific Northwest Heatwave and thinning on forest growth and SWC,as well as assessed how thinning might mitigate the heatwave's impacts in lodgepole pine forests in British Columbia,Canada.We measured meteorological data(air temperature,rainfall,solar radiation(SR),relative humidity(RH),and wind speed(W_(s)),sap flow,SWC,soil temperature(T_(s)),and tree diameters at the breast height(DBH)during the growing season(June–September)in the control(27,000 stems·ha^(-1)),lightly thinned(4,500 stems·ha^(-1)),and heavily thinned(1,100 stems·ha^(-1))experimental plots from 2018 to 2024.We found that thinning persistently and significantly(p<0.05)increased individual tree growth,with the most pronounced effects in the heavily thinned stands.The 2021 Pacific Northwest Heatwave led to an exceptionally hot growing season,significantly(p<0.05)reducing forest growth and SWC across all plots.Forest growth recovered in 2022 in the thinned plots but remained suppressed in the unthinned plots,suggesting that thinning effectively mitigated the impact of the heatwave on forest growth,while the heatwave's impacts were persistent in the unthinned plots.Our study highlights that thinning is a practical management strategy for improving tree growth and supporting climate change adaptation to extreme climate events. 展开更多
关键词 HEATWAVE THINNING Forest growth Soil water content Climate change adaptation Lodgepole pine Forest management
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Evaluation of the susceptibility to landslide geological disasters based on different slope units and an information content random forest model:a case study of the Longhua District,Shenzhen
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作者 XIONG Haoyu RAN Xiangjin XUE Linfu 《Global Geology》 2026年第1期86-100,共15页
Slope units are divided according to the real topography and have clear geological characteristics,making them ideal units for evaluating the susceptibility to geological disasters.Based on the results of automaticall... Slope units are divided according to the real topography and have clear geological characteristics,making them ideal units for evaluating the susceptibility to geological disasters.Based on the results of automatically and manually corrected hydrological slope unit division,the Longhua District,Shenzhen City,Guangdong Province,was selected as the study area.A total of 15 influencing factors,namely Fluctuation,slope,slope aspect,curvature,topographic witness index(TWI),stream power index(SPI),topographic roughness index(TRI),annual average rainfall,distance to water system,engineering rock group,distance to fault,land use,normalized difference vegetation index(NDVI),nighttime light,and distance to road,were selected as evaluation indicators.The information volume model(IV)and random points were used to select non-geological disaster units,and then the random forest model(RF)was used to evaluate the susceptibility to geological disasters.The automatic slope unit and the hydrological slope unit were compared and analyzed in the random forest and information volume random forest models.The results show that the area under the curve(AUC)values of the automatic slope unit evaluation results are 0.931 for the IV-RF model and 0.716 for the RF model,which are 0.6%(IV-RF model)and 1.9%(RF model)higher than those for the hydrological slope unit.Based on a comparison of the evaluation methods based on the two types of slope units,the hydrological slope unit evaluation method based on manual correction is highly subjective,is complicated to operate,and has a low evaluation accuracy,whereas the evaluation method based on automatic slope unit division is efficient and accurate,is suitable for large-scale efficient geological disaster evaluation,and can better deal with the problem of geological disaster susceptibility evaluation. 展开更多
关键词 geological hazards slope unit information content random forest model susceptibility assessment SHENZHEN
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Quantifying and predicting trait combinations to enhance ecological multifunctionality of urban broad-leaf forest tree species:leaf carbon content is an essential trait
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作者 Ruiting Wang Sheng Xu +3 位作者 Kexin Gao Yixin Zhang Yan Li Xingyuan He 《Journal of Forestry Research》 2026年第1期98-110,共13页
Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify... Urban forests are highly multifunctional and provide numerous ecological functions.Plant functional traits individually or jointly influence the ecological multifunctionality of tree species(TS-EMF)and can also modify TSEMF in response to environmental changes.However,there has been limited exploration of multitrait combinations for predicting TS-EMF across seasons and of trait thresholds that enhance TS-EMF.Here,for 10 dominant tree species in urban forests of Northeast China,14 traits were measured and four aboveground and three belowground ecological functions assessed in three seasons.Ecological functions and TS-EMF differed significantly throughout the seasons(P<0.05).Synergistic relationships were found between carbon sequestration and oxygen release,between cooling and humidification,and between organic carbon accumulation and nutrient cycling.Notably,aboveground multifunctionality played a leading role in TS-EMF.With seasonal changes,resource allocation shifted toward traits related to resource acquisition rather than conservation to maintain TS-EMF.The combination of traits that predicted TS-EMF varied by type,accounting for up to 66.45%of the variation.TS-EMF was primarily driven by leaf structure in spring and by nutrient accumulation in autumn.Leaf carbon content(LCC)consistently served as a stabilizing factor for predicting TS-EMF across seasons.At 36.5-36.8 mg g^(-1),LCC had its optimal effect on TS-EMF.Other traits in combination that positively influence total TS-EMF include leaf nitrogen content(3.43-3.45 mg g^(-1)),leaf phosphorus content(0.80-0.83 mg g^(-1)),and leaf area(65.86-68.43 cm^(2)).Within these specified trait thresholds,Morus alba and Quercus mongolica were identified as key species.These findings suggest that the trade-off between various ecological functions can be managed by altering plant traits across seasons.This approach could provide a theoretical foundation for enhancing the TS-EMF of urban forests through trait-based management,offering practical guidance for selecting tree species. 展开更多
关键词 Ecological multifunctionality of tree species Traits combination Urban forests Leaf carbon content
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Content Determination of Zhuang Medicine Sauropus spatulifolius Beille from Guangxi
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作者 Lixin SUN Yongshan JIN +8 位作者 Wenjing YANG Aipeng LI Yarong WEI Liangna SU Chengxu CHEN Fangyuan SHEN Yanmin LU Suoyi HUANG Lixiang LU 《Medicinal Plant》 2026年第1期1-4,共4页
[Objectives]To determine the content of Zhuang medicine Sauropus spatulifolius Beille from Guangxi.[Methods]The amino acid content of S.spatulifolius Beille was determined by ultraviolet spectrophotometry(UVs).The con... [Objectives]To determine the content of Zhuang medicine Sauropus spatulifolius Beille from Guangxi.[Methods]The amino acid content of S.spatulifolius Beille was determined by ultraviolet spectrophotometry(UVs).The content of kaempferol-3-O-gentiobioside in S.spatulifolius Beille was determined by liquid chromatography-mass spectrometry(LC-MS).Pesticide residues in S.spatulifolius Beille were detected by gas chromatography-mass spectrometry(GC-MS).Heavy metal elements arsenic(As),cadmium(Cd),and lead(Pb)in S.spatulifolius Beille were detected by inductively coupled plasma mass spectrometry(ICP-MS).[Results]The amino acid content in S.spatulifolius Beille was 3.233 mg/g,with a relative standard deviation(RSD)of 0.36%.The content of kaempferol-3-O-gentiobioside was 1.15μg/mL.No pesticide residues or heavy metals were detected in the S.spatulifolius Beille medicinal material.[Conclusions]This study improves the quality control system for S.spatulifolius Beille and provides a reference basis for the quality standard control of Zhuang medicine S.spatulifolius Beille from Guangxi. 展开更多
关键词 Zhuang medicine Sauropus spatulifolius Beille Liquid chromatography-mass spectrometry(LC-MS) Gas chromatography-mass spectrometry(GC-MS) Inductively coupled plasma mass spectrometry(ICP-MS) content determination
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Rapid vision-based system for secondary copper content estimation 被引量:2
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作者 张宏伟 葛志强 +2 位作者 袁小锋 宋执环 叶凌箭 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第8期2665-2676,共12页
A vision-based color analysis system was developed for rapid estimation of copper content in the secondary copper smelting process. Firstly, cross section images of secondary copper samples were captured by the design... A vision-based color analysis system was developed for rapid estimation of copper content in the secondary copper smelting process. Firstly, cross section images of secondary copper samples were captured by the designed vision system. After the preprocessing and segmenting procedures, the images were selected according to their grayscale standard deviations of pixels and percentages of edge pixels in the luminance component. The selected images were then used to extract the information of the improved color vector angles, from which the copper content estimation model was developed based on the least squares support vector regression (LSSVR) method. For comparison, three additional LSSVR models, namely, only with sample selection, only with improved color vector angle, without sample selection or improved color vector angle, were developed. In addition, two exponential models, namely, with sample selection, without sample selection, were developed. Experimental results indicate that the proposed method is more effective for improving the copper content estimation accuracy, particularly when the sample size is small. 展开更多
关键词 secondary copper copper content estimation sample selection color vector angle least squares support vector regression
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Effects of Relative Soil Water Content on Antioxidant Enzyme System in Malus sieversii(Lebed.) Roem 被引量:1
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作者 徐佳宁 刘钢 王文军 《Agricultural Science & Technology》 CAS 2016年第6期1281-1284,共4页
By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechan... By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechanism of M. sieversii to changes of relative soil water content. According to the results, with the decrease of relative soil water content, MDA content in M. sieversii leaves increased by mem- brane lipid peroxidation. Cells resist water stress-induced membrane lipid peroxidation and clear the increased reactive oxygen species by improving soluble protein content and SOD, POD, CAT and APX activities. However, various enzymes were involved in the response to water stress under different moisture conditions. In addition, the results indicated that M. sieversii had a good adaptability to higher relative soil water contents. 展开更多
关键词 Malus sieversii (Lebed.) Roem. Relative soil water content Membrane lipid peroxidation Antioxidant enzyme system
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Content analysis of systematic reviews on effectiveness ofTraditional Chinese Medicine 被引量:7
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作者 Junwen Wang Meng Cui +5 位作者 Hongguan Jiao Yuanyuan Tong Jun Xu Yingkai Zhao Mei Han Jianping Liu 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第2期156-163,共8页
OBJECTIVE:To evaluate evidence for the efficacy of Traditional Chinese Medicine(TCM) in systematic reviews.METHODS:Chinese(TCM Periodical Literature Database,Chinese Biological Medicine database,Chinese Medical Curren... OBJECTIVE:To evaluate evidence for the efficacy of Traditional Chinese Medicine(TCM) in systematic reviews.METHODS:Chinese(TCM Periodical Literature Database,Chinese Biological Medicine database,Chinese Medical Current Contents,China Hospital Knowledge Database journal fulltext database,Virtual Machining and Inspection System,and Wanfang) and English(Cochrane Database of Systematic Reviews,PubMed and Embase) databases were searched.RESULTS:Three thousand,nine hundred and fifty-five articles were initially identified,606 of which met the inclusion criteria,including 251 in English(83 from the Cochrane Database) and 355 in Chinese.The number of articles published each year increased between 1989 and 2009.Cardiocerebrovascular disease was the most studied target disease.Intervention measures included TCM preparations(177 articles),acupuncture(133 articles) and combinations of TCM and Western Medicine(38 articles).Control measures included positive medical(177 articles),basic treatment(100 articles),placebo(219 articles),and blank and mutual(107 articles).All articles included at least one reference;the greatest number was 268.Six of 10 articles with high quality references demonstrated curative effectsagainst target diseases including upper respiratory tract infection,dementia and depression.Interventions that were not recommended were tripterygium for rheumatoid arthritis and TCM syndrome differentiation for pediatric nocturia.In 10.4% of the studies,the authors concluded that the intervention had a curative effect.The assessors agreed with the authors' conclusions in 88.32% of cases,but rejected 8.94%(54 articles).CONCLUSION:1) Training in systematic review methods,including topic selection,study design,methods and technology,should be improved.2) Upper respiratory tract infection,dementia and depression may become the predominant diseases treated by TCM,and the corresponding interventions could be developed into practical applications.3) Use of non-recommended interventions should be controlled,and there should be more research on side effects. 展开更多
关键词 Evidence-based medicine systematicreview Traditional Chinese Medicine Curative ef-fect content analysis
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Effect of sex and rearing system on the quality and mineral content of fiber from raeini cashmere goats 被引量:8
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作者 Mehrdad Shamsaddini-Bafti Mahnaz Salehi +3 位作者 Ali Maghsoudi Ali Mostafa Tehrani Farhad Mirzaei Syed Mojtaba Syed Momen 《Journal of Animal Science and Biotechnology》 SCIE CAS 2012年第3期160-165,共6页
The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (... The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (〈1.5 years of age, n=48) were selected from flocks raised at a government breeding station or raised commercially under either rural or nomadic conditions. The staple length, cashmere fiber diameter, coefficient of variation for fiber diameter, percentage of cashmere in a fleece, percentage of guard hair in a fleece and cashmere tenacity averaged 4.6 ±0.1 cm, 18.0 ±0.1 um, 20.9±0.4%, 66.1 ± 1.5%, 33.8± 1.5% and 1.8±0.2 gf/tex, respectively. The sulfur, copper and zinc content of the cashmere averaged 2.8 ± 0.1%, 0.00065 ± 0.00002% and 0.01276 ± 0.00025%, respectively. Rearing method significantly affected staple length, coefficient of variation of fiber diameter, cashmere tenacity and copper content. Males had a higher coefficient of variation of fiber diameter and cashmere tenacity than females (P 〈 0.05). 展开更多
关键词 cashmere fiber mineral contents Raeini goat
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Analysis of the Conditional Correlations from Different Genetic Systems Between the Protein Content and the Appearance Quality Traits of Indica Rice 被引量:4
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作者 Guoke Ge Xi Zheng +2 位作者 Jianguo Wu Zihong Ye Chunhai Shi 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第2期129-137,共9页
A factorial mating design in two environments was conducted using 7 cytoplasmic male sterile lines(A)and 5 restorer lines(R)along with their F1(A×R)and F2 populations.The unconditional and conditional analyses of... A factorial mating design in two environments was conducted using 7 cytoplasmic male sterile lines(A)and 5 restorer lines(R)along with their F1(A×R)and F2 populations.The unconditional and conditional analyses of genetic models and the corresponding statistic methods,including endospermic,cytoplasmic,and maternal plant genetic systems,were used to analyze the genetic relationships between protein content(PC)and the appearance quality traits of indica rice(Oryza sativa L.).The results from unconditional analysis indicated that PC was significantly correlated with the appearance quality traits of rice,except for the brown rice thickness(BRT).Only the genetic covariance between PC and the brown rice width(BRW)was positively correlative,whereas all the other pairwise traits were negatively correlative.The results from conditional analysis revealed that the weight of brown rice(WBR)or the amylose content(AC)could significantly affect the relationships between PC and the appearance quality traits of indica rice.The conditional analysis showed that WBR might negatively affect the relationships between PC and the brown rice length(BRL),BRW,or BRT through the geuotype x environmental(GE)interaction effects,but positively affected the relationships between PC and the ratio of brown rice length to width(RLW)or the ratio of brown rice length to thickness(RLT).The amylase content could positively affect the relationships between PC and BRL,RLW,RLT through the cytoplasmic effects and maternal additive effects,but negatively affected the relationships between PC and BRW. 展开更多
关键词 indica rice(Oryza sativa L.) COVARIANCE unconditional and conditional analysis methods protein content amylose content appearance quality
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Systematic analysis of components and contents in Houttuynia cordata Thunb 被引量:5
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作者 Xin-Yi Dong Yi Jin Li-Ping Yang 《Traditional Medicine Research》 2017年第4期176-188,共13页
Objective:This study aims to provide the material basis for the molecular mechanism of Yuxingcao(Houttuynia cordata Thunb,HCT)through the method of evidence-based study to summarize the natural constituents isolated f... Objective:This study aims to provide the material basis for the molecular mechanism of Yuxingcao(Houttuynia cordata Thunb,HCT)through the method of evidence-based study to summarize the natural constituents isolated from HCT.Methods:We searched CNKI,Wanfang,VIP,Pubmed and relevant conference compilations.The keywords were'Yuxingcao or Houttuynia cordata Thunb'and'components'or'ingredients'or'constituent'or'volatile oil'or'flavonoids'or'terpene'or'content',both in Chinese and English.According to the inclusion and exclusion criteria,the reported compositions and contents have been summarized,and SPSS software was used to draw the boxplot of contents.Results:A total of 603 natural compounds in 11 categories were obtained from pooled articles.In the diverse components,the number of aliphatic compounds(n=259)and terpenoids(n=158)are more than those of flavonoids(n=26),alkaloids(n=42)and aromatics(n=42).While,in the part of volatile oils of HCT,the largest components are aliphatic compounds(mainly distributed on the ground)and terpenoids(mainly distributed in the underground).Although,methyl n-nonylketone is distributed in the whole herb plant,a large proportion is present in the underground parts.As for non-volatiles,the flavonoid content(mainly distributed on the ground)was the highest,among which quercetin and its glycosyl derivatives were the prominent.Conclusion:The results of this study provide a more comprehensive material basis for the further study of HCT.It is also helpful to explain the mechanisms of anti-oxidant,anti-inflammatory,anti-bacterial,anti-viral and anti-cancer effects from the molecular target and molecular network levels. 展开更多
关键词 Houttuynia cordata Thunb INGREDIENT content Aliphatics TERPENOIDS FLAVONOIDS
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Effect of cobalt content on electrochemical performance of La-Mg-Ni system (Ce_2Ni_7-type) electrode alloys 被引量:3
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作者 王新林 董小平 +2 位作者 张羊换 郭世海 吕反修 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期284-290,共7页
In order to improve the cyclic stability of La-Mg-Ni system (Ce2Ni7-type) alloy electrode, small amount of Co was added in La0.75Mg0.25Ni3.5 alloy. The effect of Co on electrochemical performance and microstructure ... In order to improve the cyclic stability of La-Mg-Ni system (Ce2Ni7-type) alloy electrode, small amount of Co was added in La0.75Mg0.25Ni3.5 alloy. The effect of Co on electrochemical performance and microstructure of the alloys were investigated in detail. XRD results showed that the alloys had multiphase structure composed of (La, Mg)2Ni7, LaNi5 and small amount of LaNi2 phases. The discharge capacity of the alloys first increased and then decreased with increasing Co content. At a discharge current density of 900 mA/g, the HRD of the alloy electrodes increased from 81.3% (x=0) to 89.2 % (x=0.2), and then reduced to 87.8 % (x=0.6). After 60 charge/discharge cycles, the capacity retention rate of the alloys enhanced from 52.67% to 61.32%, and the capacity decay rate of the alloys decreased from 2.60 to 2.05 mAh/g per cycle with increasing Co content. The obtained results by XPS and XRD showed that the fundamental reasons for the capacity decay of the La-Mg-Ni system (Ce2Ni7-type) alloy electrodes were corrosion and oxidation as well as passivation of Mg and Lain alkaline solution. 展开更多
关键词 Co content Ce2Ni7-type La-Mg-Ni system alloy electrochemical performance rare earths
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Content Addressable Storage Optimization for Desktop Virtualization Based Disaster Backup Storage System 被引量:3
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作者 Ruan Li Xiao Lim in Zhu Mingfa 《China Communications》 SCIE CSCD 2012年第7期1-13,共13页
This paper proposes a content addres sable storage optimization method, VDeskCAS, for desktop virtualization storage based disaster backup storage system. The method implements a blocklevel storage optimization, by em... This paper proposes a content addres sable storage optimization method, VDeskCAS, for desktop virtualization storage based disaster backup storage system. The method implements a blocklevel storage optimization, by employing the algorithms of chunking image file into blocks, the blockffmger calculation and the block dedup li cation. A File system in Use Space (FUSE) based storage process for VDeskCAS is also introduced which optimizes current direct storage to suit our content addressable storage. An interface level modification makes our system easy to extend. Experiments on virtual desktop image files and normal files verify the effectiveness of our method and above 60% storage volume decrease is a chieved for Red Hat Enterprise Linux image files. Key words: disaster backup; desktop virtualization; storage optimization; content addressable storage 展开更多
关键词 disaster backup desktop virtualization storage optimization content addressable storage
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Effects of the Dicranopteris linearis root system and initial moisture content on the soil disintegration characteristics of gully erosion 被引量:3
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作者 HE Ling DENG Yu-Song +3 位作者 TANG Qiu-yue LIAO Da-lan WANG Chao DUAN Xiao-qian 《Journal of Mountain Science》 SCIE CSCD 2022年第12期3548-3567,共20页
Benggang erosion is caused by a special type of gully erosion in southern China that seriously endangers the local ecology and environment.In this study,typical Benggang collapsing-wall soils were used as the study ar... Benggang erosion is caused by a special type of gully erosion in southern China that seriously endangers the local ecology and environment.In this study,typical Benggang collapsing-wall soils were used as the study area to investigate the effects of different initial moisture contents and dicranopteris linearis root weight densities,as well as their interactions on disintegration in orthogonal test method.The results showed that the rate of soil disintegration decreased as a linear function of the initial moisture content.The soil disintegration rate tended to rise and then fall as the root weight density increased,reflecting an optimum root weight density of 0.75-1.00 g/100 cm3.The incorporation of dicranopteris linearis roots was most effective for soil consolidation in the shallow layers of soil.In addition,the disintegration rate of the collapsing-wall soils increases as the soil layer deepened.The dicranopteris linearis root system and initial moisture content had an interactive effect that was more pronounced in deeper soils.However,the combined effect of these processes was always dominated by the initial moisture content.Moderate initial soil moisture content(0.20-0.24 g/g)and the addition of a high root density in dicranopteris linearis(0.75-1.00 g/100 cm3)were the optimal combinations that reduced the disintegration rate.In conclusion,maintaining a suitable natural moisture content in collapsing-wall soils and taking measures that use plants to consolidate soil can effectively prevent and control the occurrence of Benggang erosion.The results of this study provided further insight into the factors that influence soil disintegration and offered a scientific basis for soil erosion management in the southern China. 展开更多
关键词 Collapsing wall Initial moisture content Interactive effect Root weight density Soil disintegration
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