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Effects of Different Seed Coating Agents on the Quality of"Grey-matter"Hybrid Rice Seeds
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作者 Yuan YUAN Manzhuo TANG +7 位作者 Hanyu NING Lianghui JIANG Chunxia LU Yan WANG Chenzhong JIN Jie PENG Xinhua KUANG Yihong HU 《Agricultural Biotechnology》 CAS 2023年第3期119-124,共6页
[Objectives]This study was conducted to select suitable mixed seed coating agents for improving the quality of"grey-matter"hybrid rice seeds.[Methods]Three different mixed seed coating agents(A,B,C)were used... [Objectives]This study was conducted to select suitable mixed seed coating agents for improving the quality of"grey-matter"hybrid rice seeds.[Methods]Three different mixed seed coating agents(A,B,C)were used to coat the seeds of two varieties(Taiyou 390 and Zhenliangyou 8612)of hybrid rice with different"grey-matter"content(5%,15%,25%),and the results were investigated and compared.[Results]The combinations of treatment B(seed coating agent A+Linong)and treatment C(Manshijin+seed coating agent A)could significantly improve indexes including seed germination potential,germination rate,seed vigor,seedling height,fibrous roots and fresh weight of the two varieties with a"grey-matter"content greater than 15%,but had no significant effects on main root length,dry weight,leaf number and tiller number,and the effects of treatment B was better than those of treatment C.That is to say,mixed seed coating agent B(seed coating agent A+Linong)was suitable for use as a seed coating agent to improve the quality of"grey-matter"seeds.[Conclusions]This study provides a reference plan for the safe use of mixed seed batches with"grey-matter"deterioration. 展开更多
关键词 Hybrid rice grey-matter seed Seed coating agent Seed vigor Seedling quality
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Using Grey Target Theory for Power Quality Evaluation Based on Power Quality Monitoring Data 被引量:1
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作者 Qiang Yu Xiankai Chen +2 位作者 Xiaoyue Li Chaoqun Zhou Zhichao Li 《Energy Engineering》 EI 2022年第1期359-369,共11页
Smart grid puts forward higher requirements for power quality.Power quality evaluation can provide a decision-making basis for quality improvement.Based on power quality monitoring data,a grey target method is propose... Smart grid puts forward higher requirements for power quality.Power quality evaluation can provide a decision-making basis for quality improvement.Based on power quality monitoring data,a grey target method is proposed for power quality evaluation.The grey target is composed of power quality evaluation standard and power quality monitoring data to be evaluated.Combining with the characteristics of each power quality evaluation index,the target center of the whole grey target system is found.Then,the power quality monitoring data to be evaluated and the power quality standard mode are compared and analyzed to construct the power quality grey correlation difference information space.Finally,the target center coefficient and target degree of power quality are calculated to realize the comprehensive evaluation of power quality,and the evaluation grade of power quality monitoring data to be evaluated is obtained.Compared with the evaluation results of the existing literature,the effectiveness of the proposed method is verified,which shows that grey target theory is reasonable in the comprehensive evaluation of power quality. 展开更多
关键词 Smart grid power quality evaluation grey target theory monitoring data
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Advanced Grey Relational Analysis Method and Its Application in Water Quality Evaluation of the Lake-type Wetland
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作者 YUAN Yuan WANG Jian 《Journal of Landscape Research》 2017年第4期81-83,87,共4页
Grey relational analysis is one of the most important methods in water quality evaluation system. As the traditional grey relational analysis has the defects of homogenization in static resolution ratio, small discrim... Grey relational analysis is one of the most important methods in water quality evaluation system. As the traditional grey relational analysis has the defects of homogenization in static resolution ratio, small discrimination in correlation degree, and low precision in the weight of impact factors, this paper proposed an advanced grey relational analysis that used dynamic resolution ratio and comprehensive evaluation indicators. This method has been applied in the MIS software which monitors and evaluates the water quality in the lakes of the Four-Lake Basin. Compared with the traditional grey relational analysis and the cluster-factor analysis, this method could effectively enhance the reliability and accuracy of the results. 展开更多
关键词 Water quality evaluation Advanced grey relational analysis WETLAND
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Application of Grey Multi-hierarchy Decision to Evaluation of Stock Quality
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作者 蒋志永 欧阳建新 邓晓岚 《Journal of Southwest Jiaotong University(English Edition)》 2006年第2期187-193,共7页
In order to evaluate stock quality scientifically, a synthetic evaluation system of stock quality is proposed on the basis of fuzzy set theory and grey multi-hierarchy decision method. Then the evaluation system is ap... In order to evaluate stock quality scientifically, a synthetic evaluation system of stock quality is proposed on the basis of fuzzy set theory and grey multi-hierarchy decision method. Then the evaluation system is applied to an example. The results show that the evaluation system can overcome the errors of expert's subjective judgment. 展开更多
关键词 Stock quality grey multi-hierarchy decision Fuzzy set theory
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Fuzzy Comprehensive Evaluation of Air Quality in Shijiazhuang City Based on Grey Correlation
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作者 Zhuhong YUAN Zhenzhen ZHANG +2 位作者 Liu YANG Jing LI Degang JI 《Agricultural Biotechnology》 CAS 2020年第3期119-120,123,共3页
[Objectives]This study was conducted to evaluate the air quality of Shijiazhuang City,in order to facilitate the government to correctly formulate measures to prevent and control air pollution and protect Shijiazhuang... [Objectives]This study was conducted to evaluate the air quality of Shijiazhuang City,in order to facilitate the government to correctly formulate measures to prevent and control air pollution and protect Shijiazhuang's ambient air quality. [Methods] With the air quality data of Shijiazhuang City from February to March in 2019 as the research object,the gray correlation analysis method was used to determine weight A of each pollutant factor first,and then a single factor evaluation matrix R was constructed. The weight A and the single factor evaluation matrix R were synthesized using the M( ·,+) fuzzy composite operator,obtaining a fuzzy matrix B between the factor set and the evaluation level. [Results] The eigenvalue of air quality was calculated according to matrix B: H = 2. 259 5.[Conclusions]The air quality in Shijiazhuang City from February to March was between grade 2 and grade 3,closer to grade 2,indicating that the air quality was good. 展开更多
关键词 Fuzzy comprehensive evaluation grey correlation Air quality Shijiazhuang
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Digital Twin-based Quality Management Method for the Assembly Process of Aerospace Products with the Grey-Markov Model and Apriori Algorithm 被引量:1
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作者 Cunbo Zhuang Ziwen Liu +3 位作者 Jianhua Liu Hailong Ma Sikuan Zhai Ying Wu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2022年第5期66-86,共21页
The assembly process of aerospace products such as satellites and rockets has the characteristics of single-or small-batch production,a long development period,high reliability,and frequent disturbances.How to predict... The assembly process of aerospace products such as satellites and rockets has the characteristics of single-or small-batch production,a long development period,high reliability,and frequent disturbances.How to predict and avoid quality abnormalities,quickly locate their causes,and improve product assembly quality and efficiency are urgent engineering issues.As the core technology to realize the integration of virtual and physical space,digital twin(DT)technology can make full use of the low cost,high efficiency,and predictable advantages of digital space to provide a feasible solution to such problems.Hence,a quality management method for the assembly process of aerospace products based on DT is proposed.Given that traditional quality control methods for the assembly process of aerospace products are mostly post-inspection,the Grey-Markov model and T-K control chart are used with a small sample of assembly quality data to predict the value of quality data and the status of an assembly system.The Apriori algorithm is applied to mine the strong association rules related to quality data anomalies and uncontrolled assembly systems so as to solve the issue that the causes of abnormal quality are complicated and difficult to trace.The implementation of the proposed approach is described,taking the collected centroid data of an aerospace product’s cabin,one of the key quality data in the assembly process of aerospace products,as an example.A DT-based quality management system for the assembly process of aerospace products is developed,which can effectively improve the efficiency of quality management for the assembly process of aerospace products and reduce quality abnormalities. 展开更多
关键词 quality management Digital twin Assembly process Aerospace product grey Markov model Apriori algorithm
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Grey Clustering Evaluation on Regional Eco-environmental Quality Based on Normalized Index Value 被引量:7
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作者 TIAN Wen-xin, LI Zuo-yong, LIU Wei, YU Chun-xue College of Resources and Environmental Sciences, Chengdu University of Information Technology, Chengdu 610225, China 《Meteorological and Environmental Research》 CAS 2011年第4期65-67,71,共4页
[Objective] The aim was to assess regional eco-environmental quality by means of grey clustering method based on normalized index value. [Method] Eco-environmental quality in Chaohu basin was assessed by using grey cl... [Objective] The aim was to assess regional eco-environmental quality by means of grey clustering method based on normalized index value. [Method] Eco-environmental quality in Chaohu basin was assessed by using grey clustering method based on normalized index value, and the evaluation results were compared with those of unascertained measure method to verify the feasibility of grey clustering method used to evaluate regional eco-environmental quality. [Result] In the grey clustering assessment method based on normalized index value, indices whose standard normalized values in the same grade were close to each other were classified into one class and had the same whitening function, which reduced the number of whitening functions. Grey clustering method based on normalized index value was used to assess eco-environmental quality in Chaohu basin, and the evaluation results were basically in accordance with those of unascertained measure method, namely eco-environmental quality in Hefei, Chaohu and Lu’an belonged to the third (pass), fourth (worse) and fifth grade (bad), except for one grade difference in overall basin, and the results showed that the method had practicality and could be applied to assess regional eco-environmental quality. [Conclusion] The study could provide theoretical foundation for the establishment of comprehensive management countermeasures of regional ecological environment. 展开更多
关键词 NORMALIZATION Gray clustering method Eco-environment quality evaluation Chaohu basin China
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New developments in high quality grey cast irons 被引量:8
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作者 Iulian Riposan Mihai Chisamera Stelian Stan 《China Foundry》 SCIE CAS 2014年第4期351-364,共14页
The paper reviews original data obtained by the present authors,revealed in recent separate publications,describing specific procedures for high quality grey irons,and reflecting the forecast needs of the worldwide ir... The paper reviews original data obtained by the present authors,revealed in recent separate publications,describing specific procedures for high quality grey irons,and reflecting the forecast needs of the worldwide iron foundry industry.High power,medium frequency coreless induction furnaces are commonly used in electric melting grey iron foundries.This has resulted in low sulphur(<0.05wt.%)and aluminium(<0.005wt.%)contents in the iron,with a potential for higher superheating(>1,500°C),contributing to unfavourable conditions for graphite nucleation.Thin wall castings are increasingly produced by these electric melt shops with a risk of greater eutectic undercooling during solidification.The paper focused on two groups of grey cast irons and their specific problems:carbides and graphite morphology control in lower carbon equivalent high strength irons(CE=3.4%-3.8%),and austenite dendrite promotion in eutectic and slightly hypereutectic irons(CE=4.1%-4.5%),in order to increase their strength characteristics.There are 3 stages and 3 steps involving graphite formation,iron chemistry and iron processing that appear to be important.The concept in the present paper sustains a threestage model for nucleating flake graphite[(Mn,X)S type nuclei].There are three important groups of elements(deoxidizer,Mn/S,and inoculant)and three technological stages in electric melting of iron(superheat,pre-conditioning of base iron,final inoculation).Attention is drawn to a control factor(%Mn)x(%S)ensuring it equals to 0.03–0.06,accompanied by 0.005wt.%–0.010wt.%Al and/or Zr content in inoculated irons.It was found that iron powder addition promotes austenite dendrite formation in eutectic and slightly eutectic,acting as reinforcement for the eutectic cells.But,there is an accompanying possible negative influence on the characteristics of the(Mn,X)S type graphite nuclei(change the morphology of nuclei from polygonal compact to irregular polygonal,and therefore promote chill tendency in treated irons).A double addition(iron powder+inoculant)appears to be an effective treatment to benefit both austenite and graphite nucleation,with positive effects on the final structure and chill tendency. 展开更多
关键词 grey iron S Al Zr Ti electric melting furnace superheating PRECONDITIONING inoculation graphite nucleation graphite morphology carbides dendritic austenite iron powder
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Automotive Service Quality Investigation Using a Grey-DEMATEL Model
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作者 Phi-Hung Nguyen 《Computers, Materials & Continua》 SCIE EI 2022年第12期4779-4800,共22页
In today’s fast-challenging business environment,automobile manufacturers are required to supply customers with high-quality vehicles at competitive prices.However,existing research on factors influencing service qua... In today’s fast-challenging business environment,automobile manufacturers are required to supply customers with high-quality vehicles at competitive prices.However,existing research on factors influencing service quality lacks a detailed and systematic understanding,and there is no consensus study on causal relationship and measuring the weights of service quality factors in the automotive manufacturing industry.This study provides an integrated technique for evaluating the automotive service quality in the context of VinFast-the Vietnamese leading brand.First,the Grey Theory System(GTS)is utilized to estimate the subjective views of the decision maker(DM)and overcome incomplete and vague decision information.Then,a Decision-Making Trial and Evaluation Laboratory approach integrated with GTS(Grey-DEMATEL)is proposed not only to define the cause-effect factors but also to quantify the causal relationship of proposed criteria,which is based on comprehensive analyses of the current service quality literature and experts’opinions,as well as to capture the criteria weights.The results show that the weights of main criteria can be sorted as follow:Tangibility>Reliability>Assurance>Pricing>Empathy>Responsiveness.Among the proposed sub-criteria,Pricing is the top concern compared to other dimensions,making it a prerequisite for VinFast.The causal relationships of VinFast’s service quality are discovered by the Grey-DEMATEL technique.The findings also indicated a rising need for VinFast to focus on Empathy.Furthermore,the proposed model might be used as a decision support tool to contribute to the literature on service quality,provide recommendations for future study,and assist managers in improving service qualitymore efficiently. 展开更多
关键词 MCDM grey theory DEMATEL SERVQUAL automobile industry
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Assessment of Agricultural Soil Quality Indices Using Mechanistic Models
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作者 Mohammadali Nikpey Javad Robatjazi +3 位作者 Shahabeddin Garmehei Hendra Gonsalve W. Lasar Nguyen Khoi Nghia Benjamin Kwadwo Agyei 《Open Journal of Soil Science》 2024年第6期333-352,共20页
Assessing soil quality is a critical strategy for diagnosing soil status and anticipating concerns in land use systems for agricultural sustainability. In this study, two soil quality assessment indices, the Integrate... Assessing soil quality is a critical strategy for diagnosing soil status and anticipating concerns in land use systems for agricultural sustainability. In this study, two soil quality assessment indices, the Integrated Quality Index (IQI) and Nemoro Quality Index (NQI), were employed using two indicator selection methods: Total Data Set (TDS) and Minimum Data Set (MDS), focusing on agricultural fields in Golestan province, Iran. A total of 89 soil samples were collected and analyzed for particle size distribution, organic carbon, calcium carbonate equivalent (CCE), electrical conductivity (EC), pH, and plant-essential nutrients, including nitrogen, phosphorus, potassium, zinc, copper, manganese, and iron. Principal component analysis (PCA) was used to extract MDS from TDS, and geostatistical adaptation and correlation analyses were performed to determine the optimal soil quality evaluation index. Our results show that the exponential model better suits the spatial structure of soil quality indicators (IQIMDS: 0.955). Conformity and correlation analyses indicate that the IQI index outperformed the NQI index in estimating soil quality. The superiority of the TDS technique over the MDS technique in terms of accuracy (IQITDSs kappa: 0.155). Linear relationships between different methods showed a higher correlation coefficient (R2 = 0.43) through the application of IQI. This study suggests the use of IQIMDS to provide a reliable measurement that is particularly useful in assessing the quality of agricultural soil. 展开更多
关键词 Soil quality Geographic Information System Integrated quality Index Nemoro quality Index
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Comprehensive Evaluation Method for Traffic Flow Data Quality Based on Grey Correlation Analysis and Particle Swarm Optimization
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作者 Wei Ba Baojun Chen Qi Li 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2024年第1期106-128,共23页
Nowadays,data are more and more used for intelligent modeling and prediction,and the comprehensive evaluation of data quality is getting more and more attention as a necessary means to measure whether the data are usa... Nowadays,data are more and more used for intelligent modeling and prediction,and the comprehensive evaluation of data quality is getting more and more attention as a necessary means to measure whether the data are usable or not.However,the comprehensive evaluation method of data quality mostly contains the subjective factors of the evaluator,so how to comprehensively and objectively evaluate the data has become a bottleneck that needs to be solved in the research of comprehensive evaluation method.In order to evaluate the data more comprehensively,objectively and differentially,a novel comprehensive evaluation method based on particle swarm optimization(PSO)and grey correlation analysis(GCA)is presented in this paper.At first,an improved GCA evaluation model based on the technique for order preference by similarity to an ideal solution(TOPSIS)is proposed.Then,an objective function model of maximum difference of the comprehensive evaluation values is built,and the PSO algorithm is used to optimize the weights of the improved GCA evaluation model based on the objective function model.Finally,the performance of the proposed method is investigated through parameter analysis.A performance comparison of traffic flow data is carried out,and the simulation results show that the maximum average difference between the evaluation results and its mean value(MDR)of the proposed comprehensive evaluation method is 33.24%higher than that of TOPSIS-GCA,and 6.86%higher than that of GCA.The proposed method has better differentiation than other methods,which means that it objectively and comprehensively evaluates the data from both the relevance and differentiation of the data,and the results more effectively reflect the differences in data quality,which will provide more effective data support for intelligent modeling,prediction and other applications. 展开更多
关键词 Data quality comprehensive evaluation particle swarm optimization grey correlation analysis traffic flow data
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Effect of low-degree astigmatism on the objective visual quality
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作者 Ling-Ying Ye Shu-Feng Li +2 位作者 Jing-Jing Zuo Jin Li Hui-Xiang Ma 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第6期1086-1093,共8页
AIM:To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System(OQAS).METHODS:This study enrolled 46 participants(aged 23 to 30y,90 eyes)with normal or corr... AIM:To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System(OQAS).METHODS:This study enrolled 46 participants(aged 23 to 30y,90 eyes)with normal or corrected-to-normal vision.The cylindrical lenses(0,0.5,0.75,1.0,and 1.25 D)were placed at the axial direction(180°,45°,90°,and 135°)in front of the eyes with the best correction to form 16 types of regular low-degree astigmatism.OQAS was used to detect the objective visual quality,recorded as the objective scattering index(OSI),OQAS values at contrasts of 100%,20%,and 9%predictive visual acuity(OV100%,OV20%,and OV9%),modulation transfer function cut-off(MTFcut-off)and Strehl ratio(SR).The mixed effect linear model was used to compare objective visual quality differences between groups and examine associations between astigmatic magnitude and objective visual quality parameters.RESULTS:Apparent negative relationships between the magnitude of low astigmatism and objective visual quality were observed.The increase of OSI per degree of astigmatism at 180°,45°,90°,and 135°axis were 0.38(95%CI:0.35,0.42),0.50(95%CI:0.46,0.53),0.49(95%CI:0.45,0.54)and 0.37(95%CI:0.34,0.41),respectively.The decrease of MTFcut-off per degree of astigmatism at 180°,45°,90°,and 135°axis were-10.30(95%CI:-11.43,-9.16),-12.73(95%CI:-13.62,-11.86),-12.75(95%CI:-13.79,-11.70),and-9.97(95%CI:-10.92,-9.03),respectively.At the same astigmatism degree,OSI at 45°and 90°axis were higher than that at 0°and 135°axis,while MTFcut-off were lower.CONCLUSION:Low astigmatism of only 0.50 D can significantly reduce the objective visual quality. 展开更多
关键词 low-degree astigmatism objective visual quality Optical quality Analysis System
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Sleep quality in middle-aged and elderly hemodialysis patients:Impact of a structured nursing intervention program
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作者 Ling-Ling Tao Cai-Hua Zeng +1 位作者 Wen-Juan Mei Yan-Li Zou 《World Journal of Clinical Cases》 SCIE 2024年第25期5713-5719,共7页
BACKGROUND Poor sleep quality is common among hemodialysis patients and can significantly impact their well-being.This study aimed to evaluate the effectiveness of a structured nursing intervention program in improvin... BACKGROUND Poor sleep quality is common among hemodialysis patients and can significantly impact their well-being.This study aimed to evaluate the effectiveness of a structured nursing intervention program in improving sleep quality in middleaged and elderly hemodialysis patients.AIM To evaluate the impact of nursing intervention on sleep quality in hemodialysis patients.METHODS This cross-sectional study was conducted in a tertiary hospital,the First Affiliated Hospital of Nanchang University,in 2023.This study included 105 middle-aged and elderly hemodialysis patients aged≥45 years who underwent maintenance hemodialysis for at least 3 mo,utilizing the Pittsburgh Sleep Quality Index(PSQI)to identify poor sleepers.Those identified underwent a 12-wk nursing intervention program focusing on education,relaxation techniques,and counseling.Post-intervention,sleep quality was reassessed using the PSQI.RESULTS The study found that 68.6%of hemodialysis patients were poor sleepers.Following the 12-wk nursing intervention program,there was a significant decrease in the mean global PSQI score from 8.9±3.2 to 5.1±2.7(P<0.001),indicating improved sleep quality.This demonstrated the effectiveness of the structured nursing intervention in enhancing sleep quality for middle-aged and elderly hemodialysis patients.CONCLUSION The structured nursing intervention program focusing on sleep hygiene education,relaxation techniques,and counseling effectively improved sleep quality among middle-aged and elderly hemodialysis patients.The significant decrease in the mean global PSQI score post-intervention indicates the positive impact of tailored nursing interventions in addressing poor sleep quality in this patient population.These findings emphasize the importance of implementing targeted nursing interventions to enhance the quality of life for hemodialysis patients by addressing the prevalent issue of poor sleep quality. 展开更多
关键词 Hemodialysis patients Nursing intervention Sleep quality ELDERLY Pittsburgh Sleep quality Index Patient wellbeing
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Riparian habitat quality as an indicator of land use/land cover effects on riverine water quality
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作者 Shijie Gu Siyue Li 《Geography and Sustainability》 CSCD 2024年第1期135-143,共9页
Riparian land use/land cover(LULC)plays a crucial role in maintaining riverine water quality by altering the transport of pollutants and nutrients.Nevertheless,establishing a direct relationship between water quality ... Riparian land use/land cover(LULC)plays a crucial role in maintaining riverine water quality by altering the transport of pollutants and nutrients.Nevertheless,establishing a direct relationship between water quality and LULC is challenging due to the multi-indicator nature of both factors.Water quality encompasses a multitude of physical,chemical,and biological parameters,while LULC represents a diverse array of land use types.Riparian habitat quality(RHQ)serves as an indicator of LULC.Yet,it remains to be seen whether RHQ can act as a proxy of LULC for assessing the impact of LULC on riverine water quality.This study examines the interplay between RHQ,LULC and water quality,and develops a comprehensive indicator to predict water quality.We measured several water quality parameters,including pH(potential of hydrogen),TN(total nitrogen),TP(total phosphorus),T_(water)(water temperature),DO(dissolved oxygen),and EC(electrical conductivity)of the Yue and Jinshui Rivers draining to the Han River during 2016,2017 and 2018.The water quality index(WQI)was further calculated.RHQ is assessed by the InVEST(Integrated Valuation of Ecosystem Services and Tradeoffs)model.Our study found noticeable seasonal differences in water quality,with a higher WQI observed in the dry season.The RHQ was strongly correlated with LULC compositions.RHQ positively correlated with WQI,and DO concentration and vegetation land were negatively correlated with T_(water),TN,TP,EC,cropland,and construction land.These correlations were stronger in the rainy season.Human-dominated land,such as construction land and cropland,significantly contributed to water quality degradation,whereas vegetation promoted water quality.Regression models showed that the RHQ explained variations in WQI better than LULC types.Our study concludes that RHQ is a new and comprehensive indicator for predicting the dynamics of riverine water quality. 展开更多
关键词 Water quality index Land use/land cover Riparian habitat quality Drinking water source areas
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Implications of Dynamic Interactions between Meteorological Patterns and Surface Water Quality on Environmental Health—A Case Study of the Nairobi River
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作者 Haron Safari Hongbin Chen +1 位作者 Edwin Kipkirui Duncan Mbuge 《Journal of Geoscience and Environment Protection》 2024年第5期113-146,共34页
Urban areas face significant challenges in maintaining water quality amidst increasing urbanization and changing climatic patterns. This study investigates the complex interplay between meteorological variables and wa... Urban areas face significant challenges in maintaining water quality amidst increasing urbanization and changing climatic patterns. This study investigates the complex interplay between meteorological variables and water quality parameters in Nairobi City, focusing on the impacts of rainfall and temperature on surface water quality. Data from multiple sources, including the Water Resources Authority, Nairobi Water and Sewerage Company, and the World Bank’s Climate Change Knowledge Portal, were analyzed to assess the relationships between meteorological variables (rainfall and temperature) and water quality parameters (such as electroconductivity, biochemical oxygen demand, chloride, and pH). The analysis reveals varying impacts of rainfall and temperature on different water quality parameters. While parameters like iron and pH show strong relationships with both rainfall and temperature, others such as ammonia and nitrate exhibit moderate relationships. Additionally, the study highlights the influence of runoff, urbanization, and industrial activities on water quality, emphasizing the need for holistic management approaches. Recommendations encompass the establishment of annual publications on Nairobi River water quality, online accessibility of water quality data, development of hydrological models, spatial analysis, and fostering cross-disciplinary research collaborations. Implementing these recommendations can enhance water quality management practices, mitigate risks, and safeguard environmental integrity in Nairobi City. 展开更多
关键词 Water quality Meteorological Conditions Urban Environment Environmental Health NAIROBI Water quality Parameters
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Relationship between sleep quality and blood pressure level in nurses performing shift work
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作者 Antonina Tsipkalo Kateryna Kozak Mariya Marushchak 《Frontiers of Nursing》 2024年第1期77-84,共8页
Objective:The aim of the study was to evaluate the quality of sleep in nurses performing shift work in therapeutic and surgical depar tments and to establish possible relationships between level of blood pressure(BP)a... Objective:The aim of the study was to evaluate the quality of sleep in nurses performing shift work in therapeutic and surgical depar tments and to establish possible relationships between level of blood pressure(BP)and quality of sleep.Methods:A total of 20 nurses of the therapeutic depar tments and 20 nurses of the surgical depar tments were enrolled in the study.Sleep quality was assessed using the Pittsburgh Sleep Quality Index(PSQI).BP was measured according to the standard protocol using the Korotkoff method;a sphygmomanometer was used for this twice with an interval of 2 min between 10:00 a.m.and 10:30 a.m.The average value for the 2 indicators was calculated.The diagnosis of essential ar terial hyper tension(AH)was established according to the recommendations of the European Association of Cardiology and the European Association of Hypertension(2018).Results:The overall assessment of the sleep quality of the nurses involved in shift work indicates poor sleep quality;this was true in respondents of both the surgical and therapeutic profiles.However,it was observed that the quality of sleep was significantly lower in nurses of the therapeutic departments.Moreover,poor sleep quality was associated with AH,which was diagnosed in 65%of the nurses of the therapeutic departments and 45%of the nurses of the surgical departments,that is,in almost all of the subjects.Herewith,in the nurses of the therapeutic departments,the level of systolic BP exceeded that of the nurses of the surgical departments.Conclusions:Poor sleep quality is a significant risk factor for AH development and is relevant to nurses performing shift work.Additional clinical studies should be conducted to better understand the mechanisms underlying such adverse cardiometabolic outcomes associated with sleep disorders in the health-sector shift workers. 展开更多
关键词 blood pressure nurses shift work sleep quality Pittsburgh Sleep quality Index
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Grey associated analysis of the underground water quality effected by the leaching water of dumping area or hillock of coal mine 被引量:4
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作者 卢国斌 张浪 刘志斌 《Journal of Coal Science & Engineering(China)》 2003年第2期70-73,共4页
The underground water has been contaminated seriously by the leaching water of dumping area or hillock. To determine the pollution limits of underground water, author took samples in the study area, analyzed samples f... The underground water has been contaminated seriously by the leaching water of dumping area or hillock. To determine the pollution limits of underground water, author took samples in the study area, analyzed samples for water quality, assessed the water quality of each monitoring point by the grey associated analysis method, and gave out the classifications of the underground water quality of the study area. Comparing with fuzzy comprehensive appraisal method, it is demonstrated that grey associated analysis method is applied easily, because of its clear concept, simple and convenient calculation and excellently operation. 展开更多
关键词 灰度关联 环境质量评价 露天采煤 地下水污染
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The impact of Internet access on household dietary quality:Evidence from rural China 被引量:1
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作者 Yi Cui Qiran Zhao +1 位作者 Thomas Glauben Wei Si 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期374-383,共10页
Over the past few decades,the Internet has rapidly diffused across China.The spread of the Internet has had a profound economic and social impact on Chinese rural areas.Existing research shows that Internet access sig... Over the past few decades,the Internet has rapidly diffused across China.The spread of the Internet has had a profound economic and social impact on Chinese rural areas.Existing research shows that Internet access significantly impacts agricultural production and improves smallholder farmers’income.Beyond these,the Internet can affect other dimensions of social welfare.However,research about the impact of Internet access on dietary quality in rural China remains scarce.This study utilizes multi-period panel data from Fixed Observation Point in rural China from 2009 to 2015 to estimate the impact of Internet access on dietary quality and food consumption of rural households and conducts a causal analysis.Regression models with time and household fixed effects allow robust estimation while reducing potential issues of unobserved heterogeneity.The estimates show that Internet access has significantly increased rural household dietary quality(measured by the Chinese Diet Balance Index).Further research finds that Internet access has increased the consumption of animal products,such as aquatic and dairy products.We also examine the underlying mechanisms.Internet access improves dietary quality and food consumption mainly through increasing household income and food expenditure.These results encourage the promotion of Internet access as a valuable tool for nutritional improvements,especially in rural areas. 展开更多
关键词 dietary quality fixed effect model Internet access rural China
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Mitochondrial dysfunction and quality control lie at the heart of subarachnoid hemorrhage 被引量:2
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作者 Jiatong Zhang Qi Zhu +4 位作者 Jie Wang Zheng Peng Zong Zhuang Chunhua Hang Wei Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期825-832,共8页
The dramatic increase in intracranial pressure after subarachnoid hemorrhage leads to a decrease in cerebral perfusion pressure and a reduction in cerebral blood flow.Mitochondria are directly affected by direct facto... The dramatic increase in intracranial pressure after subarachnoid hemorrhage leads to a decrease in cerebral perfusion pressure and a reduction in cerebral blood flow.Mitochondria are directly affected by direct factors such as ischemia,hypoxia,excitotoxicity,and toxicity of free hemoglobin and its degradation products,which trigger mitochondrial dysfunction.Dysfunctional mitochondria release large amounts of reactive oxygen species,inflammatory mediators,and apoptotic proteins that activate apoptotic pathways,further damaging cells.In response to this array of damage,cells have adopted multiple mitochondrial quality control mechanisms through evolution,including mitochondrial protein quality control,mitochondrial dynamics,mitophagy,mitochondrial biogenesis,and intercellular mitochondrial transfer,to maintain mitochondrial homeostasis under pathological conditions.Specific interventions targeting mitochondrial quality control mechanisms have emerged as promising therapeutic strategies for subarachnoid hemorrhage.This review provides an overview of recent research advances in mitochondrial pathophysiological processes after subarachnoid hemorrhage,particularly mitochondrial quality control mechanisms.It also presents potential therapeutic strategies to target mitochondrial quality control in subarachnoid hemorrhage. 展开更多
关键词 mitochondrial biogenesis mitochondrial dynamics mitochondrial dysfunction mitochondrial fission and fusion mitochondrial quality control MITOPHAGY subarachnoid hemorrhage
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Significant genomic introgression from grey junglefowl(Gallus sonneratii)to domestic chickens(Gallus gallus domesticus)
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作者 Xiurong Zhao Junhui Wen +10 位作者 Xinye Zhang Jinxin Zhang Tao Zhu Huie Wang Weifang Yang Guomin Cao Wenjie Xiong Yong Liu Changqing Qu Zhonghua Ning Lujiang Qu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1482-1493,共12页
Background Chicken is one of the most numerous and widely distributed species around the world,and many studies support the multiple ancestral origins of domestic chickens.The research regarding the yellow skin phenot... Background Chicken is one of the most numerous and widely distributed species around the world,and many studies support the multiple ancestral origins of domestic chickens.The research regarding the yellow skin phenotype in domestic chickens(regulated by BCO2)likely originating from the grey junglefowl serves as crucial evidence for demonstrating the multiple origins of chickens.However,beyond the BCO2 gene region,much remains unknown about the introgression from the grey junglefowl into domestic chickens.Therefore,in this study,based on wholegenome data of 149 samples including 4 species of wild junglefowls and 13 local domestic chicken breeds,we explored the introgression events from the grey junglefowl to domestic chickens.Results We successfully detected introgression regions besides BCO2,including two associated with growth trait(IGFBP2 and TKT),one associated with angiogenesis(TIMP3)and two members of the heat shock protein family(HSPB2 and CRYAB).Our findings suggest that the introgression from the grey junglefowl may impact the growth performance of chickens.Furthermore,we revealed introgression events from grey junglefowl at the BCO2 region in multiple domestic chicken breeds,indicating a phenomenon where the yellow skin phenotype likely underwent strong selection and was retained.Additionally,our haplotype analysis shed light on BCO2 introgression event from different sources of grey junglefowl into domestic chickens,possibly suggesting multiple genetic flows between the grey junglefowl and domestic chickens.Conclusions In summary,our findings provide evidences of the grey junglefowl contributing to the genetic diversity of domestic chickens,laying the foundation for a deeper understanding of the genetic composition within domestic chickens,and offering new perspectives on the impact of introgression on domestic chickens. 展开更多
关键词 BCO2 Domestic chickens grey junglefowl INTROGRESSION
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