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Water Quality,Influential Factors,and Management Strategies from 2016 to 2020 in the Yangtze River Economic Belt,China
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作者 LIN Lanyu GUO Congrong +6 位作者 CHEN Yanan HE Lihuan YAN Luyu FANG Dekun MA Guangwen ZHANG Fengying LI Mingsheng 《Chinese Geographical Science》 2025年第1期175-186,共12页
The Yangtze River economic belt(YREB),China is important to the Chinese economy and for supporting sustainable development.Clarifying the relationship between water quality indices and socioeconomic indicators could h... The Yangtze River economic belt(YREB),China is important to the Chinese economy and for supporting sustainable development.Clarifying the relationship between water quality indices and socioeconomic indicators could help improve aquatic environment management in the YREB and our understanding of the causes and effects of water quality variations in other large river basins.In this study,river water quality,factors affecting water quality,and management strategies,and correlations between water quality indices and socioeconomic indicators in the YREB during the 13th Five-Year Plan period(2016-2020)were assessed.The single-factor evaluation method,constant price for GDP,and correlation analyses were adopted.The results showed that:1)water quality in the YREB improved during the 13th Five-Year Plan period.The number of aquatic environment sections meeting GradeⅠ-Ⅲwater quality standards increased by 13.1%and the number below Grade V decreased by 2.9%.2)The values of 12 indicators in the YREB exceeded relevant standards.The indicators with highest concentreation were the total phosphorus,chemical oxygen demand,ammonia nitrogen,and permanganate index,which were relatively high in downstream regions in Anhui Province,Jiangsu Province,and Shanghai Municipality.3)Ammonia nitrogen,chemical oxygen demand,and total phosphorus emissions per unit area and water extraction per unit area are relatively high in the three downstream regions mentioned above.4)Increased domestic sewage discharges have increased total wastewater discharges in the YREB.5)River water quality in the YREB strongly correlated with population,economic,and water resource indices and less strongly correlated with government investment,agriculture,meteorology,energy,and forestry indices.This confirmed the need to decrease wastewater discharges and non-point-source pollutant emissions.The aquatic environment could be improved by taking reasonable measures to control population growth,adjusting the industrial structure to accelerate industrial transformation and increase the proportion of tertiary industries,and investing in technological innovations to protect the environment. 展开更多
关键词 water quality factors coping strategies Yangtze River economic belt(YREB) China
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Effects of air damping on quality factors of different probes in tapping mode atomic force microscopy
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作者 Yu Zeng Guo-Lin Liu +1 位作者 Jin-Hao Liu Zheng Wei 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期506-519,共14页
The AFM probe in tapping mode is a continuous process of energy dissipation,from moving away from to intermittent contact with the sample surfaces.At present,studies regarding the energy dissipation mechanism of this ... The AFM probe in tapping mode is a continuous process of energy dissipation,from moving away from to intermittent contact with the sample surfaces.At present,studies regarding the energy dissipation mechanism of this continuous process have only been reported sporadically,and there are no systematic explanations or experimental verifications of the energy dissipation mechanism in each stage of the continuous process.The quality factors can be used to characterize the energy dissipation in TM-AFM systems.In this study,the vibration model of the microcantilever beam was established,coupling the vibration and damping effects of the microcantilever beam.The quality factor of the vibrating microcantilever beam under damping was derived,and the air viscous damping when the probe is away from the sample and the air squeeze film damping when the probe is close to the sample were calculated.In addition,the mechanism of the damping effects of different shapes of probes at different tip–sample distances was analyzed.The accuracy of the theoretical simplified model was verified using both experimental and simulation methods.A clearer understanding of the kinetic characteristics and damping mechanism of the TM-AFM was achieved by examining the air damping dissipation mechanism of AFM probes in the tapping mode,which was very important for improving both the quality factor and the imaging quality of the TM-AFM system.This study’s research findings also provided theoretical references and experimental methods for the future study of the energy dissipation mechanism of micro-nano-electromechanical systems. 展开更多
关键词 TM-AFM quality factors air viscous damping air squeeze film damping
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Dynamic Development Characteristics and Driving Factors of High Quality Development Level in China’s Five Major Urban Agglomerations
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作者 ZOU Weiyong XU Lingli 《Chinese Geographical Science》 SCIE CSCD 2024年第5期777-790,共14页
High-quality development is the primary task of comprehensively building a socialist,modern country,as well as the primary task of building urban agglomerations in China.Based on the five development concepts,this pap... High-quality development is the primary task of comprehensively building a socialist,modern country,as well as the primary task of building urban agglomerations in China.Based on the five development concepts,this paper used the entropy method to measure the High Quality Development Index(HQDI)of the five major urban agglomerations.The results showed that the HQDI of the five major urban agglomerations shows a fluctuating upward trend.First,using the Dagum Gini coefficient to explore the sources of HQDI development differences in urban agglomerations,we found that the main source of HQDI differences in urban agglomerations was inter-regional differences,while intra-regional differences were not important.Second,kernel density estimation was used to test the dynamic evolution trend of HQDI within urban agglomerations.There was a polarisation phenomenon in the HQDI of urban agglomerations,such as the Pearl River Delta urban agglomeration and the Chengdu-Chongqing urban agglomeration.But overall,the degree of imbalance had decreased.Third,using geographic detectors to examine the driving factors of HQDI in urban agglomerations,we found that the main driving forces for improving HQDI in urban agglomerations were economic growth,artificial intelligence technology and fiscal decentralisation.All the interaction factors had greater explanatory power for the spatial differentiation of HQDI,which can be divided into two types:two-factor improvement and non-linear improvement.This study is conducive to improving and enriching the theoretical system for evaluating the high quality development of urban agglomerations,and provides policy references for promoting the high quality development of urban agglomerations. 展开更多
关键词 urban agglomeration High quality Development Index(HQDI) spatio-temporal evolution driving factors
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A Problem Not to Be Ignored: The Influencing Factors of Mobile Phone Addiction and Its Influence on Sleep Quality
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作者 Zihan Ji Lian Zhou 《Health》 2024年第5期459-469,共11页
Background and Objective: With the popularity and widespread use of mobile phones, the effects of mobile phone dependence and addiction on individuals’ physical and mental health have attracted more and more attentio... Background and Objective: With the popularity and widespread use of mobile phones, the effects of mobile phone dependence and addiction on individuals’ physical and mental health have attracted more and more attention. The present study aims to analyze the current state of mobile phone addiction and its impact on sleep quality within the population, while also exploring the influence of related factors on sleep quality. Ultimately, this research will provide a scientific foundation for targeted intervention measures and strategies. Methods: A total of 253 permanent residents in Nanjing were randomly selected as study subjects. The Mobile Phone Addiction Index (MPAI) and Pittsburgh Sleep Quality Index (PSQI) were used to evaluate the degree of smartphone addiction and sleep quality of the study subjects. Body mass index (BMI) was measured according to standardized procedures. Independent sample t-test, Chi-square test, rank sum test and multiple linear regression were used to analyze the correlation between mobile phone addiction and sleep quality, and P Results: 117 people (46.2%) were addicted to mobile phones. Chi-square test showed that the rate of mobile phone addiction in drinking group was significantly higher than that in non-drinking group (P P P P P P P P P P Conclusion: Mobile phone addiction may lead to shorter sleep duration and reduce sleep efficiency. The withdrawal of mobile phone addiction may have a negative impact on sleep quality. According to the characteristics of the population, appropriate comprehensive intervention measures should be taken to build an effective evaluation system, so as to reduce the impact of mobile phone addiction and withdrawal problems on sleep and improve sleep quality. 展开更多
关键词 Mobile Phone Addiction Influencing factors WITHDRAWAL Sleep quality
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Analysis and Strategy Research on Influencing Factors of Classroom Teaching Quality in Higher Vocational Colleges
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作者 Qian Qian Wang Ma.Agatha Anne D.Dizon 《Journal of Contemporary Educational Research》 2024年第4期199-203,共5页
In this study,the questionnaire“Influencing Factors of Classroom Quality in Higher Vocational Education”was self-compiled.By using the questionnaire survey method,the research conclusion was drawn that the main fact... In this study,the questionnaire“Influencing Factors of Classroom Quality in Higher Vocational Education”was self-compiled.By using the questionnaire survey method,the research conclusion was drawn that the main factors affecting the classroom teaching quality in higher vocational education were teaching and student factors,teacher factors,and classroom factors based on 2,683 samples.According to the research results,the measures to improve the quality of classroom teaching are put forward,in order to provide guidance for improving the quality of teaching in higher vocational colleges. 展开更多
关键词 Higher vocational colleges Classroom teaching quality Influencing factor
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Effect of Main Cultivation Factors on Quality Combination Parameters of High-quality Brassica napus Hybrids 被引量:4
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作者 赵继献 王仙平 高志宏 《Agricultural Science & Technology》 CAS 2013年第5期738-749,753,共13页
[Objective] This study aimed to analyze the influence of five cultivation factors including sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount and potash fertilizer amount on the quali... [Objective] This study aimed to analyze the influence of five cultivation factors including sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount and potash fertilizer amount on the quality parameters of Brassica napus hybrid& [Method] Statistical analysis on the data from previous studies and our work was carried out [Result] The contents of erucic acid, thioglycoside, oil, oleic acid and linoleic acid were negatively correlated with the sowing date, while the contents of seed protein, palmitic acid, stearic acid and linolenic acid were positively correlated with the sowing date. The total amount of fat and protein, the ratio of unsaturated fatty acid (UFA) to saturated fatty acid (SFA), the fatty acid (FA) of erucic acid chain, the total amount of oleic acid and linoleic acid were negatively correlated with the sowing date; the UFA content, the unsatu- ration index, the SFA content, the 18-C FA content, and the ratio of UFA to FA in erucic acid chain were positively correlated with the sowing date. The contents of erucic acid, thioglycoside, seed protein, oleic acid, linolenic acid and eicosenoic acid were negatively correlated with the plant density, while the contents of oil, palmitic acid, stearic acid and linoleic acid were positively correlated with the plant density. The total amount of fat and protein (F & P), and the ratio of UFA to FA in erucic acid chain were negatively correlated with the plant density, while the UFA content, the unsaturation index, the SFA content, the ratio of UFA to SFA, the 18-C FA content, the FA in erucic acid chain, and the total amount of oleic acid and linoleic acid were positively correlated with the plant density. The contents of erucic acid, thioglycoside, oil, protein in milled rapeseed, palmitic acid and eicosenoic acid were negatively correlated with the nitrogen fertilizer amount, while the contents of seed protein, oleic acid, stearic acid, linoleic acid and linolenic acid were posi- tively correlated with the nitrogen fertilizer amount; the total F & P, the unsaturation index and the ratio of UFA to FA in erucic acid chain were positively correlated with the nitrogen fertilizer amount, while the UFA content, the SFA content, the FA in erucic acid chain, the total amount of oleic acid and linoleic acid, the ratio of UFA to SFA, and the 18-C FA content were negatively correlated with the nitrogen fertilizer amount The contents of erucic acid, thioglycoside, seed protein, linoleic acid and linolenic acid were negatively correlated with the potash fertilizer amount, while contents of oil, oleic acid, stearic acid and eicosenoic acid were positively correlated with the potash fertilizer amount; the total F & P, the unsaturation index, the SFA, and the ratio of UFA to FA in erucic acid chain were negatively correlated with the potash fertilizer amount There were negative correlations between the contents of erucic acid, thioglycoside, seed protein, palmitic acid, stearic acid, linoleic acid, linolenic acid and phosphate fertilizer amount; positive correlations between the contents of oil, oleic acid, eicosenoic acid and phosphate fertilizer amount The total UFA, the unsaturation index, the 1843 FA, the SFA, the FA in erucic acid chain, and the ratio of UFA to FA in erucic acid chain were negatively correlated with the phosphate fertilizer amount [Conclusion] This study identified the correlations of the five cultivation factors with the quality parameters of high-quality Brassica napus hybrids, to provide theoretical basis for its cultivation. 展开更多
关键词 Cultivation factors quality traits quality combination traits Influence
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Effect of Main Cultivation Factors on Oil Quality and Stability of Brassica napus Hybrids 被引量:1
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作者 赵继献 杜才富 +2 位作者 任廷波 程国平 王仙萍 《Agricultural Science & Technology》 CAS 2014年第5期795-800,共6页
[Objective] This study aimed to analyze the influence of five cultivation factors: sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount and potash fertilizer amount on oil quality and ... [Objective] This study aimed to analyze the influence of five cultivation factors: sowing date, plant density, nitrogen fertilizer amount, phosphate fertilizer amount and potash fertilizer amount on oil quality and stability of Brassica napus hybrids. [Method] Statistical analysis was carried out based on the data from previous studies and our work. [Result] Sowing date had no significant influence on oil quality and stability of B. napus hybrids. The plant density shared a positive correlation with 18-C fatty acid (FA) content, unsaturated fatty acid (UFA) content, total content of linoleic acid and linolenic acid, index of unsaturated fatty acid (IUFA), so a large plant density can improve the oil quality (by increasing18-C FA content, UFA content, total content of linoleic acid and linolenic acid), but reduce the oil stability (by increasing IUFA). The amount of nitrogen fertilizer had no significant influence on the contents of 18-C FA and UFA, but significant positive correlations with the total content of linoleic acid and linolenic acid and IUFA. So, the total content of linoleic acid and linolenic acid can be reduced by increasing nitrogen amount, meanwhile the oil stability was also decreased. Phosphate fertilizer amount did not affect 18-C FA significantly, but was negatively correlated with the UFA content, total content of linoleic acid and linolenic acid, and IUFA. So, increasing the amount of applied phosphate fertilizer can reduce UFA content, total content of linoleic acid and linolenic acid, thereby improving oil stability. Potash fertilizer had no significant influence on the IUFA, a significant positive correlation with 18-C FA content, an insignificant positive correlation with the the UFA content, and a negative correlation with the total content of linoleic acid and linolenic acid. The oil content of rapeseed shared an extremely significant positive correlation with 18-C FA content and UFA content, an negative correlation with the total content of linoleic acid and linolenic acid, and no significant correlation with IUFA. [Conclusion] This study identified the effects of five main cultivation factors on oil quality and stability of B. napus hybrids, and the correlations of oil content with 18-C FA content, UFA content, total content of linoleic acid and linolenic acid, and IUFA. 展开更多
关键词 Brassica napus hybrids Cultivation factors Oil quality Oil stability INFLUENCE
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INTEGRATION OF HUMAN FACTORS ENGINEERING AND QUALITY MANAGEMENT 被引量:1
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作者 卢岚 秦嵩 +1 位作者 陆全 Dessouky MohomedI 《Transactions of Tianjin University》 EI CAS 2001年第3期178-181,共4页
Human factors engineering and quality management are different research branches in the field of industrial engineering.A basis for interaction based on the concepts and techniques of human factors engineering and qua... Human factors engineering and quality management are different research branches in the field of industrial engineering.A basis for interaction based on the concepts and techniques of human factors engineering and quality management with some practical examples of cooperative effect is defined in this paper.The specific challenges about the quality management in manufacturing and service are presented to demonstrate that the human factors analysis of quality problems leads to new tends for integrated development. 展开更多
关键词 human factors engineering quality management integrated development cooperative effect
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Comparison of Mode Quality Factors for Equilateral Triangular, Square and Rhombus Optical Micro-Resonators
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作者 黄永箴 国伟华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第2期117-120,共4页
The mode frequencies and the quality factors for the equilateral triangular resonator (ETR), the square resonator (SR) and the rhombus resonator (RR) are numerically calculated by the finite difference time domai... The mode frequencies and the quality factors for the equilateral triangular resonator (ETR), the square resonator (SR) and the rhombus resonator (RR) are numerically calculated by the finite difference time domain technique and the Padé approximation. The numerical results show that the resonant modes confined in an equilateral triangular cavity have much higher quality factors than those in the square or the rhombus cavities. The modes in the ETR are totally confined in transverse direction while those in the SR and RR are only partly confined. For the ETR with the side length of 4μm and the refractive index of 3 2, the mode quality factor of about 5 5×10 3 at the wavelength of 1 55μm has been obtained. 展开更多
关键词 MICRORESONATOR quality factor resonant frequency finite difference time domain technique semiconductor laser
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Analysis of quality factors for Rayleigh channel waves 被引量:5
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作者 杨小慧 曹思远 +2 位作者 李德春 于鹏飞 张浩然 《Applied Geophysics》 SCIE CSCD 2014年第1期107-114,118,共9页
To facilitate investigation of the effect of imperfect elastic dissipation on the propagation of Rayleigh-type channel waves and use of their quality factors in investigations of the properties of coal seams, a simple... To facilitate investigation of the effect of imperfect elastic dissipation on the propagation of Rayleigh-type channel waves and use of their quality factors in investigations of the properties of coal seams, a simple method for calculating the quality factor QR is proposed in this paper. Introduction of complex velocities into the dispersion function allows calculation of the dispersion function of Rayleigh-type channel waves in coal seams. By the control variable method, we analyzed changes in QR with changes in coal seam thickness and P- and S-wave Q-factors within the coal seam and adjacent rock layers. The numerical results show that the trend of the QR curve is consistent with the group velocity curve. The minimum QR value occurs at the Airy phase frequency; the Airy phase frequency decreases as coal seam thickness increases. The value of QR increases with increasing QS2(quality factor for S wave in coal seam). We can compensate for the absorption of Rayleigh-type channel waves using the computed QR curve. Inversion of the QR curve can also be used to predict the thicknesses and lithologies of coal seams. 展开更多
关键词 Coal seam RAYLEIGH channel wave DISPERSION curve attenuation quality factor
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Estimation of quality factors by energy ratio method 被引量:2
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作者 王宗俊 曹思远 +5 位作者 张浩然 曲英铭 袁殿 杨金浩 张德龙 邵冠铭 《Applied Geophysics》 SCIE CSCD 2015年第1期86-92,122,123,共9页
The quality factor Q, which reflects the energy attenuation of seismic waves in subsurface media, is a diagnostic tool for hydrocarbon detection and reservoir characterization. In this paper, we propose a new Q extrac... The quality factor Q, which reflects the energy attenuation of seismic waves in subsurface media, is a diagnostic tool for hydrocarbon detection and reservoir characterization. In this paper, we propose a new Q extraction method based on the energy ratio before and after the wavelet attenuation, named the energy-ratio method(ERM). The proposed method uses multipoint signal data in the time domain to estimate the wavelet energy without invoking the source wavelet spectrum, which is necessary in conventional Q extraction methods, and is applicable to any source wavelet spectrum; however, it requires high-precision seismic data. Forward zero-offset VSP modeling suggests that the ERM can be used for reliable Q inversion after nonintrinsic attenuation(geometric dispersion, refl ection, and transmission loss) compensation. The application to real zero-offset VSP data shows that the Q values extracted by the ERM and spectral ratio methods are identical, which proves the reliability of the new method. 展开更多
关键词 quality factor Q energy ratio time domain seismic wavelet spectral ratio method
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Factors influencing quality of bowel preparation for colonoscopy 被引量:13
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作者 Ronald V Romero Sanjiv Mahadeva 《World Journal of Gastrointestinal Endoscopy》 CAS 2013年第2期39-46,共8页
Recent technological advances in colonoscopy have led to improvements in both image enhancement and procedural performance.However,the utility of these technological advancements remain dependent on the quality of bow... Recent technological advances in colonoscopy have led to improvements in both image enhancement and procedural performance.However,the utility of these technological advancements remain dependent on the quality of bowel preparation during colonoscopy.Poor bowel preparation has been shown to be associated with lower quality indicators of colonoscopy performance,such as reduced cecal intubation rates,increased patient discomfort and lower adenoma detection.The most popular bowel preparation regimes currently used are based on either Polyethylene glycol-electrolyte,a non-absorbable solution,or aqueous sodium phosphate,a lowvolume hyperosmotic solution.Statements from various international societies and several reviews have suggested that the efficacy of bowel preparation regimes based on both purgatives are similar,although patients' compliance with these regimes may differ somewhat.Many studies have now shown that factors other than the type of bowel preparation regime used,can influence the quality of bowel preparation among adult patients undergoing colonoscopy.These factors can be broadly categorized as either patient-related or procedure-related.Studies from both Asia and the West have identified patient-related factors such as an increased age,male gender,presence of co-morbidity and socioeconomic status of patients to be associated with poor bowel preparation among adults undergoing routine out-patient colonoscopy.Additionally,procedure-related factors such as adherence to bowel preparation instructions,timing of bowel purgative administration and appointment waiting times for colonoscopy are recognized to influence the quality of colon cleansing.Knowledge of these factors should aid clinicians in modifying bowel preparation regimes accordingly,such that the quality of colonoscopy performance and delivery of service to patients can be optimised. 展开更多
关键词 BOWEL PREPARATION COLONOSCOPY RISK factors quality
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Effects of Meteorological Factors on the Yield and Quality of Special Rice in Different Periods after Anthesis 被引量:4
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作者 Ying Xuan Yang Yi +5 位作者 He Liang Shanqing Wei Ligeng Jiang Izhar Ali Saif Ullah Quan Zhao 《Agricultural Sciences》 2019年第4期451-475,共25页
In order to investigate the effect of meteorological factors on the yield and quality of special rice during the filling stage, an experiment was conducted with 10 special rice varieties which were planted in three di... In order to investigate the effect of meteorological factors on the yield and quality of special rice during the filling stage, an experiment was conducted with 10 special rice varieties which were planted in three different regions during spring 2017. The results showed that the quality traits and yields from different regions of the same variety were different, which reached up to a significant level in most varieties. Among the quality traits, the grain chalkiness rate and chalkiness degree were the most sensitive to different climatic factors, and changes were found among them in different regions, while minor variation was found between brown rice rate and white rice rate. The parameters that were severely affected by temperature were gel consistency, gelatinization temperature, brown rice rate and yield during the filling stage. The critically affected factors by heat were brown rice rate, protein content, essential amino acid and amylose content while brown rice rate, chalkiness rate and gelatinization temperature were substantially affected by water factors. Grain yield and quality were closely related to meteorological factors on different stages after heading. Our results revealed that yield and quality of special rice were significantly influenced by meteorological factors during the grain filling stage. 展开更多
关键词 NOODLE RICE FEED RICE METEOROLOGICAL factors quality YIELD
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Subjective sleep quality in perimenopausal women and its related factors 被引量:3
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作者 Jianping Zhang Fen Li Yongjie Lin Qiu Sheng Xuewen Yu Xinwen Zhang 《Journal of Nanjing Medical University》 2007年第2期116-119,共4页
Objective: To evaluate the sleep quality and its related factors among perimenopausal women. Methods: A self-designed questionnaire was administered to 506 perimenopausal women. The questionnaire included the influe... Objective: To evaluate the sleep quality and its related factors among perimenopausal women. Methods: A self-designed questionnaire was administered to 506 perimenopausal women. The questionnaire included the influencing factors on the sleep quality, the Pittsburgh Sleep Quality Index (PSQI), the Zung Self-Rating Depression Scales (SDS), the Zung Self-Rating Anxiety (SAS) and the Modified Kupperman Index (KI). Data were analyzed by SPSSll.5. Results: The mean PSQI was 5.97±4.30. Twenty-four percent of perimenopausal women reported poor sleep. Age and perimenopausal symptoms were significantly correlated with sleep quality. The sleep quality of the 45~49 age group was the poorest and the 40~44 age group was the best. The women who had higher Kupperman index were more likely to be poor sleepers. There was no significant correlation between occupation and sleep quality. Night sweat, depression, anxiety, hot flash, stressful life event, and regular exercise were significantly and independently related with sleep quality. Among them, regular exercise was a protective factor of sleep quality. Conclusion: High incidence of poor sleep quality exists among perimenopausal women. Some effective interventions Should be taken to improve the sleep quality of perimenopausal women. 展开更多
关键词 perimenopausal women sleep quality influencing factor
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Research on quality changes and influencing factors of groundwater in the Guanzhong Basin 被引量:2
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作者 TAO Hong ZHENG Miao-miao +5 位作者 FAN Li-min LI Wen-li DING Jia LI Hui HE Xu-bo TAO Fu-ping 《Journal of Groundwater Science and Engineering》 2017年第3期296-302,共7页
This paper studies the distribution features, the chemical elements beyond standards and the influencing factors of shallow groundwater quality in the Guanzhong Basin through the data monitored in the last twenty year... This paper studies the distribution features, the chemical elements beyond standards and the influencing factors of shallow groundwater quality in the Guanzhong Basin through the data monitored in the last twenty years. The final purpose is to comprehensively evaluate the divisions of groundwater quality in the Guanzhong Basin. Results show that, the groundwater quality is in good shape, and suitable for drinking. Drinking accounts for 16.02% of the total, most of which are distributed in the lubotan of Weibei. Some come from loess plateau of Qian-Liquan County and some are generated by the industrial pollution of Xingping City. Materials exceeding standards include chloride, sulfate, three nitrogen, fluoride, manganese, iron, hexavalent chromium and so on. The main factors influencing the quality of shallow groundwater include groundwater exploitation, natural background value of special components and precipitation, among which the groundwater exploitation poses the greatest impact. The depth of water is positively correlated with the concentration of sulfate, nitrate and total hardness. 展开更多
关键词 Groundwater quality Comprehensive assessment Influencing factor Excessive substance Guanzhong Basin
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Advances in the Study of Protein Quality Traits and Main Influencing Factors of Wheat in China 被引量:2
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作者 李娜娜 蒲艳艳 +5 位作者 孔维国 宫永超 贾文斌 辛富刚 于彦丽 丁汉凤 《Agricultural Science & Technology》 CAS 2015年第8期1653-1659,共7页
Wheat, the third major grain crop in China, is an important source of hu- man proteins. Wheat quality and yield has a direct impact on the development of agricultural economy and food industry. Investigating and impro... Wheat, the third major grain crop in China, is an important source of hu- man proteins. Wheat quality and yield has a direct impact on the development of agricultural economy and food industry. Investigating and improving protein quality of wheat has become a key to solving the contradiction. This paper reviewed the exist- ing literature published at home and abroad, analyzed the present situation and ex- isting problems of wheat protein quality in China, summarized the latest research progress about genetic models, main influencing factors, and correlations between protein quality traits and other traits, discussed current issues in the improvement of wheat protein quality, and proposed suggestions for breeding high-quality wheat, aiming at providing theoretical basis for genetic improvement, planting structure ad- justment and efficient production of high-quality wheat. 展开更多
关键词 WHEAT quality analysis Genetic model Influencing factor quality im-provement ADVANCE
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Epidemiological, Clinical Aspects and Factors Associated with Typical Gastroesophageal Reflux Disease in the General Population of Parakou, Republic of Benin
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作者 Saké Khadidjatou Tamou Sambo Bio Elie +3 位作者 Zinsou Jocelyne Abla Dovonou Comlan Albert Sehonou Jean Kodjoh Nicolas 《Open Journal of Gastroenterology》 CAS 2024年第2期41-58,共18页
Introduction: Gastroesophageal reflux disease (GERD) is a benign and chronic disease that can impair the quality of life. Objective: To study the epidemiological, clinical aspects and factors associated with typical G... Introduction: Gastroesophageal reflux disease (GERD) is a benign and chronic disease that can impair the quality of life. Objective: To study the epidemiological, clinical aspects and factors associated with typical GERD in the general population of Parakou in the Republic of Benin. Methods: This was a descriptive and analytical cross-sectional study with prospective data collection which took place from May 1, 2019 to June 30, 2019. The study population consisted of any subject aged at least 15 years and living in Parakou. Subjects aged at least 15 years, present on the day of the survey and having given their free and informed verbal consent were included. The Short form of QRS®(Reflux-Qual Short form) questionnaire and the “Hospital Anxiety and Depression” score were used to assess the quality of life and anxiety/depression, respectively. The sampling was probabilistic through a 2-stage cluster sampling. The variable of interest was the presence of GERD. Results: Out of 390 subjects surveyed, 28 had symptoms of typical GERD, representing a prevalence of 7.18%. The average age of these subjects was 27.11 ± 7.88 years. Fifteen subjects (53.57%) were male, giving a sex ratio of 1.15. Fourteen (50%) had a secondary level of education, 12 (42.86%) were pupils/students, 18 (64.29%) were single. The monthly income of 22 subjects (78.57%) was lower than the guaranteed interprofessional minimum wage (40,000 FCFA). The average duration of progression of symptoms was 15.89 ± 4.97 months. Symptoms occurred less than twice a week in 22 subjects (78.57%). The clinical manifestations were both diurnal and nocturnal in 12 subjects (42.86%). None of the 28 subjects with GERD had clinical warning signs. Asthma, diabetes, consumption of high fat or spice foods, carbonated drinks, non-steroidal anti-inflammatory drugs, alcoholic beverages and tobacco were statistically associated with the occurrence of GERD. Each of the 28 subjects had at least one associated factor. A significant impair in quality of life was observed in 27 patients (96.43%). Conclusion: Typical GERD is relatively common in the general population of Parakou in the Republic of Benin. It often affects young males. Among the risk factors identified, the most common are carbonated drinks, spicy meals and diabetes. GERD significantly impairs quality of life. Raising awareness about the disease and its associated factors is necessary among the general population. 展开更多
关键词 Gastroesophageal Reflux Disease EPIDEMIOLOGY General Population Associated factors quality of Life Parakou
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Ecological environmental quality evaluation and driving factor analysis of the Lijiang River Basin,based on Google Earth Engine
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作者 WEI Xi YANG Dazhi +2 位作者 CAI Xiangwen SHAO Ya TANG Xiangling 《中国生态农业学报(中英文)》 CAS CSCD 北大核心 2024年第9期1592-1608,共17页
For regional ecological management,it is important to evaluate the quality of ecosystems and analyze the underlying causes of ecological changes.Using the Google Earth Engine(GEE)platform,the remote sensing ecological... For regional ecological management,it is important to evaluate the quality of ecosystems and analyze the underlying causes of ecological changes.Using the Google Earth Engine(GEE)platform,the remote sensing ecological index(RSEI)was calculated for the Lijiang River Basin in Guangxi Zhuang Autonomous Region for 1991,2001,2011,and 2021.Spatial autocorrelation analysis was employed to investigate spatiotemporal variations in the ecological environmental quality of the Lijiang River Basin.Furthermore,geographic detectors were used to quantitatively analyze influencing factors and their interaction effects on ecological environmental quality.The results verified that:1)From 1991 to 2021,the ecological environmental quality of the Lijiang River Basin demonstrated significant improvement.The area with good and excellent ecological environmental quality in proportion increased by 19.69%(3406.57 km^(2)),while the area with fair and poor ecological environmental quality in proportion decreased by 10.76%(1860.36 km^(2)).2)Spatially,the ecological environmental quality of the Lijiang River Basin exhibited a pattern of low quality in the central region and high quality in the periphery.Specifically,poor ecological environmental quality characterized the Guilin urban area,Pingle County,and Lingchuan County.3)From 1991 to 2021,a significant positive spatial correlation was observed in ecological environmental quality of the Lijiang River Basin.Areas with high-high agglomeration were predominantly forests and grasslands,indicating good ecological environmental quality,whereas areas with low-low agglomeration were dominated by cultivated land and construction land,indicating poor ecological environmental quality.4)Annual average precipitation and temperature exerted the most significant influence on the ecological environmental quality of the basin,and their interactions with other factors had the great influence.This study aimed to enhance understanding of the evolution of the ecological environment in the Lijiang River Basin of Guangxi Zhuang Autonomous Region and provide scientific guidance for decision-making and management related to ecology in the region. 展开更多
关键词 Ecological environmental quality Remote sensing ecological index Driving factor Google Earth Engine Lijiang River Basin
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Research Progress of Factors Influencing the Yield and Quality of Flue-cured Tobacco 被引量:2
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作者 杨静 陈杰 +2 位作者 杨如松 唐军 黄浩 《Agricultural Science & Technology》 CAS 2015年第4期820-825,共6页
The key factors infIuencing the yield and quality of fIue-cured tobacco were summarized: the cIimate factors (incIuding temperature, iI umination and mois-ture) and cuItivation factors (incIuding transpIant, ferti... The key factors infIuencing the yield and quality of fIue-cured tobacco were summarized: the cIimate factors (incIuding temperature, iI umination and mois-ture) and cuItivation factors (incIuding transpIant, fertiIization, maturity and harvest). The key factors infIuencing fIue-cured tobacco yield and quality in cuItivation process were eIaborated, so as to provide reference for research advance of fIue-cured to-bacco production technoIogy. 展开更多
关键词 FIue-cured tobacco YleId quality InfIuencing factor
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Factors Affecting Quality and Granulating Property of Pellet Feed 被引量:1
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作者 LI Yan-cong WAN Zhi-sheng +1 位作者 SHAN Hui-yong SONG Xin 《Animal Husbandry and Feed Science》 CAS 2011年第1期5-6,10,共3页
In order to ensure quality of pellet feed and improve production performance of animals, factors affecting the quality and granulating property of pellet feed were analyzed from the aspects of raw materials, process a... In order to ensure quality of pellet feed and improve production performance of animals, factors affecting the quality and granulating property of pellet feed were analyzed from the aspects of raw materials, process and equipments. The effects of these factors on production of pellet feed decline in the following order: composition and proportion of raw materials; material fineness; refining temperature and other refining factors; equipments like ring die and press roller; and cooling and drying conditions 展开更多
关键词 Pellet feed quality Granulating property factors
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