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Multi-nutrient fertilization-based analysis of fruit quality and mineral element composition during fruit development in Merlot wine grapevines
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作者 Xiaolong Wang Xuedong Shao +7 位作者 Zhengwen Zhang Xiaomin Zhong Xiaohao Ji Xiangbin Shi Chang Liu Zhiqiang Wang Fengzhi Liu Haibo Wang 《Journal of Integrative Agriculture》 2025年第4期1503-1514,共12页
Mineral elements play a crucial role in plant growth and development.Ensuring the proper supply of these elements in the soil to maintain the optimum range within plants is necessary for achieving optimal fruit yield ... Mineral elements play a crucial role in plant growth and development.Ensuring the proper supply of these elements in the soil to maintain the optimum range within plants is necessary for achieving optimal fruit yield and quality.Unfortunately,the application of NPKCaMg fertilizers to fruit trees is often either insufficient or excessive,leading to environmental degradation and reduced fruit yield and quality.To assess the impacts of different fertilizers on the biological traits of grapes and their responses to nutritional elements,Merlot grapevines were subjected to multi-nutrient fertilization over four consecutive growing seasons from 2018 to 2021 in Penglai District,Yantai,China.Principal component analysis revealed that the T11 treatment,consisting of N_(3)P_(3)K_(1)Ca_(2)Mg_(4),was the most suitable fertilizer type and application design among the treatments.The application of T11 resulted in a significantly lower(24.29–35.20%)fertilizer usage,and it resulted in increases in several important traits such as100-grain weight(HGW),number of seeds(SN),total soluble solids(TSS),total seed phenols(SP),seed flavanols(SFI),and seed tannins(ST)by 3.28–12.84%,3.76–20.03%,1.11–14.95%,2.16–23.69%,11.00–32.78%,and1.07–23.35%,respectively,compared to the T14(N_(4)P_(2)K_(3)Ca_(1)Mg_(4)),T16(N_(4)P_(4)K_(1)Ca_(3)Mg_(2)),T13(N_(4)P_(1)K_(4)Ca_(2)Mg_(3)),and T15(N_(4)P_(3)K_(2)Ca_(4)Mg_(1))treatments.Flowering and fruiting processes exhibited a considerable demand for NPK,with higher requirements for K and B during fruit growth and development compared to the other macroelements and micronutrients,respectively.Excessive K in soil enhanced the competitive inhibition of Ca uptake by Merlot grapevines.The optimal ranges of mineral element contents for total peel phenols(PP),peel flavanols(PFI),total peel flavonoids(PFD),total seed phenols(SP),and seed tannins(ST)were primarily influenced by grape variety and nutritional analysis method.In conclusion,the careful selection of NPKCaMg fertilizer and its precise application to soil at an optimum range of mineral elements is critical for grapevine growth and development. 展开更多
关键词 fruit quality mineral element optimum range MERLOT
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Quality Control Technology for Hourly Routine Meteorological Element Data Files
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作者 Hui LIANG Xianqiang SU +1 位作者 Qingyun ZHU Xiao HUANG 《Meteorological and Environmental Research》 2025年第3期10-15,共6页
[Objective]In response to the issue of insufficient integrity in hourly routine meteorological element data files,this paper aims to improve the availability and reliability of data files,and provide high-quality data... [Objective]In response to the issue of insufficient integrity in hourly routine meteorological element data files,this paper aims to improve the availability and reliability of data files,and provide high-quality data file support for meteorological forecasting and services.[Method]In this paper,an efficient and accurate method for data file quality control and fusion processing is developed.By locating the missing measurement time,data are extracted from the"AWZ.db"database and the minute routine meteorological element data file,and merged into the hourly routine meteorological element data file.[Result]Data processing efficiency and accuracy are significantly improved,and the problem of incomplete hourly routine meteorological element data files is solved.At the same time,it emphasizes the importance of ensuring the accuracy of the files used and carefully checking and verifying the fusion results,and proposes strategies to improve data quality.[Conclusion]This method provides convenience for observation personnel and effectively improves the integrity and accuracy of data files.In the future,it is expected to provide more reliable data support for meteorological forecasting and services. 展开更多
关键词 Integral point Meteorological elements Data file quality control
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Correlation Analysis between Quality Characteristics and Fruit Mineral Element Contents in 'Fuji' Apples
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作者 张强 李兴亮 +3 位作者 李民吉 周贝贝 张军科 魏钦平 《Agricultural Science & Technology》 CAS 2017年第2期212-218,共7页
[Objective] The aims were to explore the relationship between the contents of fruit mineral elements and quality features of the 'Fuji' apple, screen major mineral elements of the fruit affecting fruit quality featu... [Objective] The aims were to explore the relationship between the contents of fruit mineral elements and quality features of the 'Fuji' apple, screen major mineral elements of the fruit affecting fruit quality features, and set up optimum proposals of fruit mineral elements for good fruit qualities, so as to provide a theoretical basis for the reasonable orchard soil and foliar fertilizer applications to increase fruit quality and reduce the physiological diseases related to the 'Fuji' apple. [Methods] The fruit mineral elements and quality indicators of 'Fuji" apples were in- vestigated and analyzed, which were collected from the 153 commercial apple or- chards of "Fuji' apple located in 51 counties. The variable importance for projection (VlP) of partial least squares regression (PLS) method was used to analyze the model effect and weight analysis impact of the fruit mineral element contents to fruit quality, screen out major factors of fruit mineral elements influencing the different fruit qualities, and set up the regression equation of the fruit qualities and major fruit mineral elements. Linear programming was used to obtain optimum proposals of the fruit mineral elements to achieve good 'Fuji' apple qualities. [Results] The mineral elements content and quality characteristics in "Fuji' apple fruit had great differences in the different produce regions in which the maximum content of nitro- gen, iron, zinc and boron in the 'Fuji' fruit were12.06, 6.17, 7.7, and 10.08 times greater than the minimum respectively, and the differences for titratable acid and the SSC/TA ratio were 2.33 and 2.16 times respectively. The correlation analysis between the fruit mineral element contents and qualities showed that the nitrogen content of fruit had a significantly negative correlation with the soluble solid content, SSC/TA ratio and red color area, while the calcium and iron contents in the fruit were in significantly positive correlation with the soluble solid content and SSC/TA ratio. The model effect and weight analysis showed that the content of nitrogen and iron in the fruit had a greater influence on the integral fruit quality, followed by phosphorus, potassium and calcium. The variable importance for projection (VlP) technology of PLS found that the mean fruit weight was primarily affected by nitro- gen, phosphorus and potassium, and the soluble solid was primarily affected by ni- trogen, calcium and iron, while the red color area was primarily affected by nitro- gen, potassium, calcium, iron and zinc. The regression equation between fruit quality and mineral element contents showed that the mean fruit weight had a greater pos- itive effect coefficient with the content of phosphorus and potassium, and a greater negative effect coefficient with the content of nitrogen in the fruit. Moreover, the sol- uble solid had the largest negative effect coefficient with nitrogen and largest posi- tive effect coefficient with calcium and iron in the fruit. [Conclusion] The maximum content of soluble solid and titratable acid were 1.5 times more than the minimum, and nitrogen, iron, zinc and boron were 6 times more than in the 'Fuji' apple fruit in the different produce regions. Therefore, it is a key technological measure to improve the overall qualities of the "Fuji' apple by decreasing the content of nitrogen, and increasing the contents of iron, phosphorus, potassium and calcium in the fruit. 展开更多
关键词 "Fuji' apple Fruit mineral element Fruit quality Partial least squares regression (PLS) Optimum proposals
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Comprehensive Evaluation on the Irrigation Water Quality in Turpan City Based on Matter Element Analysis Method 被引量:1
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作者 阿不都沙拉木.加拉力丁 王欣 师芸宏 《Agricultural Science & Technology》 CAS 2016年第1期239-244,共6页
Matter-element analysis method was used to construct the comprehensive matter-element model for the evaluation of the quality of various kinds of irrigation water in Turpan City to evaluate the quality of irrigation w... Matter-element analysis method was used to construct the comprehensive matter-element model for the evaluation of the quality of various kinds of irrigation water in Turpan City to evaluate the quality of irrigation water(such as river water,spring water, Karez well water, pumped well water) in Turpan City, Xinjiang. The results showed that the quality of the irrigation water was the best in October,which was in Grade I or Grade 2; in May, the quality of some of the irrigation water became poorer to Grade II, which was easy to soil salinization; in March, the detected qualities of the water samples water from the Meiyaogou basin were all in Grade IV, which was not suitable for farmland irrigation. The comparison on the evaluation results of matter-element analysis and fuzzy evaluation method showed that the results of the 2 methods were almost consistent with each other, and showed good uniformity. 展开更多
关键词 Matter element analysis Irrigation water Water quality evaluation Turpan City
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Correlation of Plant Morphological and Grain Quality Traits with Mineral Element Contents in Yunnan Rice 被引量:5
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作者 ZENG Ya-wen SHEN Shi-quan +4 位作者 WANG Lu-xiang LIU Jia-fu Pu Xiao-ying Du Juan Qiu Min 《Rice science》 SCIE 2005年第2期101-106,共6页
Correlations between four grain quality, 24 plant morphological traits and eight element contents of 653 accessions from Yunnan rice were analyzed. P, K, Ca and Mg contents of core collection were closely correlated t... Correlations between four grain quality, 24 plant morphological traits and eight element contents of 653 accessions from Yunnan rice were analyzed. P, K, Ca and Mg contents of core collection were closely correlated to the most plant morphological and grain quality traits, and there were highly significant correlations (P 〈0.01) among some traits including P content to number of stems and tillers, K content and amylose content, Ca content and plant height, Mg content and protein content. Mn, Zn, Cu and Fe contents of core collection were closely related to a few traits, such as Fe content and gel consistency (-0.1121^**), Zn content and seed setting rate (-0.1411^**), Cu content and number of grains per panicle (-0.1398^**), Mn content and plant height (-0.2492^**). 展开更多
关键词 mineral elements morphological traits cooking quality core collection Yunnan Province RICE
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Influence of Geometric Design Variable and Bone Quality on Stress Distribution for Zirconia Dental Implants-A 3D Finite Element Analysis 被引量:2
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作者 Duraisamy Velmurugan Masilamany Santha Alphin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2018年第11期125-141,共17页
This study aims to investigate the effects of variable thread pitch on stress distribution in bones of different bone qualities under two different loading conditions(Vertical,and Horizontal)for a Zirconia dental impl... This study aims to investigate the effects of variable thread pitch on stress distribution in bones of different bone qualities under two different loading conditions(Vertical,and Horizontal)for a Zirconia dental implant.For this purpose,a three dimensional finite element model of the mandibular premolar section and three single threaded implants of 0.8 mm,1.6 mm,2.4 mm pitch was designed.Finite element analysis software was used to develop the model and three different bone qualities(Type II,Type III,and Type IV)were prepared.A vertical load of 200 N,and a horizontal load of 100 N was applied at the abutment surface.The von-Mises stress criterion was used to analyze the results.The crestal bony-region of the mandibular section was subjected to maximum von-Mises stresses for all bone qualities.The outcome of this study indicates that,horizontal loading had more influence on stress distribution than vertical loading,regardless of the bone qualities and pitch values.Varying the dental implant pitch does not cause any decrease in stress distribution in bone,when the bone density decreased.The study concluded that implants with minimum pitch values induced lesser stress values at the implant-bone interface. 展开更多
关键词 BONE quality FINITE element ANALYSIS IMPLANT stress.
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APPLICATION OF SUB-ELEMENT AND MICRO-ELEMENT IN BEM WITH ROLLER BEARING LOAD 被引量:5
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作者 ShuXuedao XingXidong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第3期423-426,共4页
Aiming at the discontinuous traction on contact elements of roller bearing,new concepts of sub- and micro-element are put forward. In the sub-element and micro-element,traction influence coefficient has been modified,... Aiming at the discontinuous traction on contact elements of roller bearing,new concepts of sub- and micro-element are put forward. In the sub-element and micro-element,traction influence coefficient has been modified, which is calculated by the former boundary elementmethod (BEM) with roller bearing load. Hence, three-dimensional distribution of load on rollerbearing is calculated accurately. In practice, it has been proved that this method has highercalculation accuracy. An effective numerical method is offered for analyzing load characteristics ofroller bearing to improve service longevity of roller bearing and operation efficiency of rollingmill. 展开更多
关键词 sub-element Micro-element BEM
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Regression Analysis of Nutrient Elements between Soil and Tobacco Leaves and Their Influences on Aroma Quality of Flue-cured Tobacco 被引量:1
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作者 Xueqin XU Xiaolan LI +2 位作者 Zhiyan CHEN Defen ZENG Aifei XU 《Agricultural Science & Technology》 CAS 2014年第3期493-498,共6页
This study aimed to analyze the relationship between nutrient elements K, Ca, Mg, Cu, Mn, Zn and Fe in tobacco-planting soils and tobacco leaves from six main tobacco-producing areas, and to investigate the influences... This study aimed to analyze the relationship between nutrient elements K, Ca, Mg, Cu, Mn, Zn and Fe in tobacco-planting soils and tobacco leaves from six main tobacco-producing areas, and to investigate the influences of these elements on chemical composition and aroma components in tobacco leaves. Results showed that there were certain relationship between contents of nutrient elements in tobacco-planting soils and contents of corresponding elements in tobacco leaves; various elements exhibited different influences on the aroma quality of flue-cured tobacco. Based on the actual situation of nutrient contents in soils from different tobaccoproducing areas, contents of various elements in tobacco leaves should be regulated by soil fertilization and foliar spraying, thereby improving the aroma quality of flue-cured tobacco. 展开更多
关键词 SOIL TOBACCO Nutrient elements Regression analysis Aroma quality
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Evaluation on environmental quality for heavy metal elements of Xihe soil 被引量:1
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作者 Aijun WU 《Global Geology》 2008年第4期209-213,共5页
According to "Environmental quality standard for soil" and using As,Cd,Cr,Cu,Hg,Ni,Pb,Zn elements as evaluation index,the author evaluated soil environmental quality in Xihe area of Shenyang.The results show... According to "Environmental quality standard for soil" and using As,Cd,Cr,Cu,Hg,Ni,Pb,Zn elements as evaluation index,the author evaluated soil environmental quality in Xihe area of Shenyang.The results show that the soil in Xihe area is polluted rifely by heavy metal elements.The polluted areas are mainly distributed near the upstreams of Xihe River,Shenxin River and Shenliao irrigation canal.There exist large distinctions among the heavy metal elements to the pollution degree.Cd pollution area is the biggest and the most serious in pollution degree. 展开更多
关键词 Xihe SOIL heavy metal element environmental quality
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Water quality evaluation based on improved fuzzy matter-element method 被引量:23
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作者 Dongjun Liu Zhihong Zou 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第7期1210-1216,共7页
For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. Th... For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. The coefficient of variation of each indicator is used to determine the weight instead of traditional calculating superscales method. On the other hand, fuzzy matter-elements are constructed, and normal membership degrees are used instead of traditional trapezoidal ones. The composite fuzzy matter-elements with associated coefficient are constructed through associated transformation. The levels of natural water quality are determined according to the principle of maximum correlation. The improved fuzzy matter-element evaluation method is applied to evaluate water quality of the Luokou mainstream estuary at the first ten weeks in 2011 with the coefficient of variatiola method determining the weights. Water quality of Luokou mainstream estuary is dropping from level I to level II. The results of the improved evaluation method are basically the same as the official water quality. The variation coefficient method can reduce the workload, and overcome the adverse effects from abnormal values, compared with the traditional calculating superscales method. The results of improved fuzzy matter- element evaluation method are more credible than the ones of the traditional evaluation method. The improved evaluation method can use information of monitoring data more scientifically and comprehensively, and broaden a new evaluation method for water quality assessment. 展开更多
关键词 water quality improved fuzzy matter-element evaluation method synthetic evaluation variation coefficient method normal membership Key words: water quality improved fuzzy matter-element evaluation method synthetic evaluation variation coefficient method normal membership
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Selection of raw materials and control of trace elements for production of high-quality SG iron
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作者 Jia-xin Bai 《China Foundry》 SCIE 2019年第2期79-87,共9页
During the production of SG iron, the selection of raw materials and control of chemical composition are most important. From the very early days of SG iron production, the effects of trace elements on graphite form a... During the production of SG iron, the selection of raw materials and control of chemical composition are most important. From the very early days of SG iron production, the effects of trace elements on graphite form and matrix structure have been studied, and the allowable concentration limits for their detrimental influence has been decreased year by year, during the last fifty years. This paper has reviewed some of the suggested SG iron trace elements in the literature and in several Chinese foundries. It was found that for most SG iron castings, rare earth elements are still required to neutralize the harmful effects of trace elements and improve SG iron quality. It also found that the use of high purity and ultra-high purity base iron melts enabled integrated, safety-critical and complicated SG iron castings of varying thickness, and heavy-section, to be produced successfully. These SG iron castings have surprisingly good structures, and their mechanical and dynamic properties are vastly superior to those specified in current international SG iron standards. Further study is required on the effects of using high purity and ultra-high purity base melts on the structure and properties of SG iron. 展开更多
关键词 trace elements anti-nodulizing and PEARLITE factors chunky graphite HIGH and ultra-high PURITY pig IRON HIGH quality SG IRON
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Estimating and Plotting of Groundwater Quality Using WQI UA and GIS in Assiut Governorate, Egypt 被引量:2
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作者 Mohamed R. El Tahlawi Mohamed Abo-El Kassem +1 位作者 Gamal. Y. Baghdadi Hussein A. Saleem 《World Journal of Engineering and Technology》 2016年第1期59-70,共12页
This paper aims to turn complex groundwater data into comprehensible information by indexing the different factors numerically comparative to the standards of World Health Organization (WHO) to produce Water Quality I... This paper aims to turn complex groundwater data into comprehensible information by indexing the different factors numerically comparative to the standards of World Health Organization (WHO) to produce Water Quality Index (WQI). Water Quality Index (WQI) has been used to assess groundwater quality and Geographic Information Systems (GIS) has been used to create maps representing the spatial distribution of groundwater categories in Assiut governorate, Egypt. Water Quality Index has been computed by Un-weighted Arithmetic Water Quality Index (WQIUA) method and applied on 796 wells over eight years from 2006 to 2013. The results showed that WQIUA values for drinking purposes were high and most of them reached higher or close to 100, which indicated that the groundwater was polluted and unsafe for drinking. On the other hand, the quality index of groundwater for irrigation purposes in most of the study area ranges between 55.78 and 78.38 (poor and very poor category);this means that groundwater is moderately polluted and rather suitable for irrigation. 展开更多
关键词 Un-Weighted Arithmetic Water quality Index (WQI<sub> UA sub>) Groundwater Pollution Geographic Information Systems (GIS)
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2D Finite Element Analysis of Asynchronous Machine Influenced Under Power Quality Perturbations
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作者 Jasmin Pamela S R.Saranya +5 位作者 V.Indragandhi R.Raja Singh V.Subramaniyaswamy Yuvaraja Teekaraman Shabana Urooj Norah Alwadai 《Computers, Materials & Continua》 SCIE EI 2022年第3期5745-5763,共19页
Asynchronous machines are predominantly preferred in industrial sectors for its reliability.Power quality perturbations have a greater impact on industries;among the different power quality events,voltage fluctuations... Asynchronous machines are predominantly preferred in industrial sectors for its reliability.Power quality perturbations have a greater impact on industries;among the different power quality events,voltage fluctuations are the most common and that may cause adverse effect on machine’s operation since they are longer enduring.The article discusses a numerical technique for evaluating asynchronous motors while taking into account magnetic saturation,losses,leakage flux,and voltage drop.A 2D linear analysis involving a multi-slice time stepping finite element model is used to predict the end effects.As an outcome,the magnetic saturation and losses are estimated using amodified 2D nonlinear time-stepping finite element formulation.The method takes the electromagnetic fields at the ends of the motor into account using limited computer resources.The proposed method will greatly reduce computation timewith limited computer resources for analyzing themachine’s performance with high precision.The analyzed findings assist in preventing voltage variance issues in the power network system and provide suggestions for developing a robust system. 展开更多
关键词 Asynchronous machine finite element model analysis voltage variations power quality multi-slice model
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Diagnosis Delay and Assessment of the Quality of Life of Patients with Endometriosis Using the Endometriosis Health Profile 5 Questionnaire in a Sub-Saharan Population
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作者 Monzango Sibo Mboloko Esimo +16 位作者 Mputu Lobota Itewa Monka Kitenge Kia Kayembe Tambola Grace Samba Kevine Maesheka Patrick Ntanga Kabuya Amba Naomie Maxime Fastrez Buka Ikoko Ndjukendi Ally Sangana Georges Barhayiga Berthe Mbanzulu Pita Longo Mbenza Clément Ferrier Emile Darai 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第5期907-917,共11页
Context: Endometriosis is a pathology that directly affects the daily lives of women with frequent impairment of their quality of life. In our environment, medical, socio-cultural, financial factors and factors relate... Context: Endometriosis is a pathology that directly affects the daily lives of women with frequent impairment of their quality of life. In our environment, medical, socio-cultural, financial factors and factors related to the organization of the health care system greatly delay its diagnosis. The objectives of the present study were to determine the diagnosis delay and to assess the quality of life before surgery of women with endometriosis using the specific Endometriosis Health Profile 5 (EHP-5) questionnaire. Methods: We carried out a descriptive, observational, retrospective study in 8 medical centers in the City of Kinshasa, from January 2019 to October 2022. A total of 80 women with endometriosis confirmed by laparoscopy (16 diagnostic and 64 operative laparoscopies) and histopathology were interviewed. We used the revised American Society for Reproductive Medicine (rASMR) classification, the Endometriosis Fertility Index (EFI) score was calculated for infertile women and the EHP-5 questionnaire to assess quality of life. Our data was entered and analyzed using Statistical Analysis Software 16.1 (STATA 16.1). Results: Diagnosis delay of endometriosis was on average 12 ± 4.3 years. The overall mean EHP-5 score of all patients showed a severe deterioration in quality of life (604 ± 235). A negative relationship was observed between the age of the patient, the diagnostic delay, and the alteration of the quality of life in patients over 36 years old and those with about 11 years of diagnostic delay presenting the slight alteration. Patients with a high social level had very severe quality impairment. Women on hormonal treatment, those with a history of pregnancy, childbirth, miscarriage and abortion had a slight and significant deterioration in quality of life (p 0.05). Conclusion: Despite some limitations, our preliminary study highlights that in sub-Saharan Africa, the diagnosis of endometriosis is delayed and associated with a severe alteration in quality of life. Moreover, diagnosis of endometriosis seems to be restricted to women with high social levels. Therefore, further efforts are required to develop a health policy to decrease delay for diagnosis with potential benefits on symptoms, quality of life, fertility while limiting stigma and psychological effects of this debilitating pathology. 展开更多
关键词 Diagnosis Delay EHP-5 ENDOMETRIOSIS quality of Life sub-Saharan
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COMPUTATION OF STRESS INTENSITY FACTORS BY THE SUB-REGION MIXED FINITE ELEMENT METHOD OF LINES
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作者 Yuan Si Xu Yongjun WILLIAMS F W 《Acta Mechanica Solida Sinica》 SCIE EI 2007年第2期149-162,共14页
Based on the sub-region generalized variationM principle, a sub-region mixed version of the newly-developed semi-analytical 'finite element method of lines' (FEMOL) is proposed in this paper for accurate and effic... Based on the sub-region generalized variationM principle, a sub-region mixed version of the newly-developed semi-analytical 'finite element method of lines' (FEMOL) is proposed in this paper for accurate and efficient computation of stress intensity factors (SIFs) of two-dimensional notches/cracks. The circular regions surrounding notch/crack tips are taken as the complementary energy region in which a number of leading terms of singular solutions for stresses are used, with the sought SIFs being among the unknown coefficients. The rest of the arbitrary domain is taken as the potential energy region in which FEMOL is applied to obtain approximate displacements. A mixed system of ordinary differential equations (ODEs) and algebraic equations is derived via the sub-region generalized variational principle. A singularity removal technique that eliminates the stress parameters from the mixed equation system eventually yields a standard FEMOL ODE system, the solution of which is no longer singular and is simply and efficiently obtained using a standard general-purpose ODE solver. A number of numerical examples, including bi-material notches/cracks in anti-plane and plane elasticity, are given to show the generally excellent performance of the proposed method. 展开更多
关键词 stress intensity factors finite element method of lines sub-region generalized variational principle ordinary differential equation solver
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Object-Based Classification of Urban Distinct Sub-Elements Using High Spatial Resolution Orthoimages and DSM Layers
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作者 Ali Nouh Mabdeh A'kif Al-Fugara Mu’men Al jarah 《Journal of Geographic Information System》 2018年第4期323-343,共21页
This paper aims to assess the ways in which multi-resolution object-based classification methods can be used to group urban environments made up of a mixture of buildings, sub-elements such as car parks, roads, shades... This paper aims to assess the ways in which multi-resolution object-based classification methods can be used to group urban environments made up of a mixture of buildings, sub-elements such as car parks, roads, shades and pavements and foliage such as grass and trees. This involves using both unmanned aerial vehicles (UAVs) which provide high-resolution mosaic Orthoimages and generate a Digital Surface Model (DSM). For the study area chosen for this paper, 400 Orthoimages with a spatial resolution of 7 cm each were used to build the Orthoimages and DSM, which were georeferenced using well distributed network of ground control points (GCPs) of 12 reference points (RMSE = 8 cm). As these were combined with onboard RTK-GNSS-enabled 2-frequency receivers, they were able to provide absolute block orientation which had a similar accuracy range if the data had been collected by traditional indirect sensor orientation. Traditional indirect sensor orientation involves the GNSS receiver in the UAV receiving a differential signal from the base station through a communication link. This allows for the precise position of the UAV to be established, as the RTK uses correction, allowing position, velocity, altitude and heading to tracked, as well as the measurement of raw sensor data. By assessing the results of the confusion matrices, it can be seen that the overall accuracy of the object-oriented classification was 84.37%. This has an overall Kappa of 0.74 and the data that had poor classification accuracy included shade, parking lots and concrete pavements. These had a producer accuracy (precision) of 81%, 74% and 74% respectively, while lakes and solar panels each scored 100% in comparison, meaning that they had good classification accuracy. 展开更多
关键词 OBJECT-ORIENTED Classification Real Time KINEMATICS DSM UAV Orthoimages MOSAIC URBAN DISTINCT sub-elements
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Effects of Traditional Chinese Medicine Five-element Music Combined with Acupoint Application on Perioperative Sleep Quality in Patients Undergoing Joint Replacement Surgery 被引量:1
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作者 Gu Lidan Wang Qiuju 《World Journal of Integrated Traditional and Western Medicine》 2019年第1期45-49,共5页
OBJECTIVE: To explore the effects of traditional Chinese medicine(TCM) five-element music combined with acupoint application on perioperative sleep quality in patients undergoing joint replacement surgery. METHODS: In... OBJECTIVE: To explore the effects of traditional Chinese medicine(TCM) five-element music combined with acupoint application on perioperative sleep quality in patients undergoing joint replacement surgery. METHODS: In this study, a total of 122 patients with joint replacement surgery in Beijing Jishuitan Hospital were targeted from 2015 to 2018. All patients were grouped by random number table method. Among them, 61 patients with routine nursing were included in the control group. On this basis, the other 61 patients with acupoint application and TCM five-element music therapy were included as the observation group. 2 weeks later, the Pittsburgh Sleep Quality Index(PSQI) was used to evaluate sleep quality in all patients. The sleep improvement of the 2 groups was evaluated, and the patient was assessed for anxiety and depression, and the curative efficacy was evaluated. RESULTS: After 2 weeks of nursing, the PSQI of the patients improved significantly. The PSQI of the observation group was only 6.6 ± 2.4, and the control group decreased to 9.9 ± 2.7. The observation group was better than the control group, and the difference was statistically significant(P < 0.05). Comparing the 2 groups, the anxiety score of the observation group decreased to 4.8 ± 1.6, which was significantly lower than that of 6.9 ± 2.2 in the control group. The depression score of the observation group decreased to 4.6 ± 1.3, which was significantly lower than that of 6.8 ± 2.3 in the control group. In the control group, the negative emotion scores after nursing were better than those before nursing, and the difference was statistically significant(P < 0.05). Comparing the 2 groups, the effective rate of sleep improvement in the observation group was 96.6%, and the cure rate was as high as 49.1%. The control group was 82.0%, and the cure rate was 18.0%. The observation group was better than the control group, and the difference was statistically significant(P < 0.05). CONCLUSION: The combination of TCM five-element music with acupoint application can improve the perioperative sleep quality of patients undergoing joint replacement surgery, and it can help patients to relieve negative emotions. It is worth promoting. 展开更多
关键词 Traditional Chinese medicine five-element MUSIC ACUPOINT application Joint REPLACEMENT surgery SLEEP quality
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发展农业新质生产力,赋能农业高质量发展 被引量:11
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作者 闫亚飞 崔俊辉 《中国科学院院刊》 北大核心 2025年第3期561-570,共10页
科技创新驱动生产力发展,进而形成新质生产力,这是我国基于现阶段实践发展与战略部署提出的新概念。加快农业领域科技创新,驱动形成农业新质生产力是推进我国农业高质量发展的迫切需求和关键着力点。立足现实来看,当前我国农业高质量发... 科技创新驱动生产力发展,进而形成新质生产力,这是我国基于现阶段实践发展与战略部署提出的新概念。加快农业领域科技创新,驱动形成农业新质生产力是推进我国农业高质量发展的迫切需求和关键着力点。立足现实来看,当前我国农业高质量发展还面临着自然禀赋较差,关键技术“卡脖子”,农业人才短缺,农业生产方式落后,农业体制机制不完善等问题。鉴于此,文章研究认为,以农业新质生产力赋能农业高质量发展的实现路径应当是:强化耕地保护,利用技术创新促进耕地的量和质双提升,维护好耕地生态环境,进一步保障粮食安全;加快农业科技创新发展,提升农业产业效能;以科技创新完善农业生产方式,推动实现农业绿色发展;推进农业与数字产业的深度融合,提升产业链供应链韧性;提升农业人才质量,建设多层次、多元化人才队伍;优化农业发展体制机制建设,促进科技创新良性循环,优化市场资源配置。 展开更多
关键词 农业新质生产力 高质量发展 科技创新 要素配置
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数据要素赋能、质态变迁与制造业新质生产力 被引量:8
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作者 宋炜 王杰 +1 位作者 周勇 董明放 《科技进步与对策》 北大核心 2025年第1期21-29,共9页
新发展格局下,制造业新质生产力不仅取决于数据要素赋能,而且受到开放型经济新体制中质态变迁的影响。利用2010—2022年中国制造业面板数据,探讨数据要素赋能与质态变迁对制造业新质生产力的影响。在区分数据要素赋能类型的基础上纳入... 新发展格局下,制造业新质生产力不仅取决于数据要素赋能,而且受到开放型经济新体制中质态变迁的影响。利用2010—2022年中国制造业面板数据,探讨数据要素赋能与质态变迁对制造业新质生产力的影响。在区分数据要素赋能类型的基础上纳入质态变迁,结果发现,数据要素偏向型赋能引致的质态变迁无法持续承接全球价值链中高端技术革命性突破,会阻碍制造业创新发展,因而对制造业新质生产力的促进作用不显著。数据要素增强型赋能引致的质态变迁能够大幅提升制造业生产系统的复杂性,以及制造业创新系统的前沿性,促进创新发展动力演化,对中国制造业新质生产力发挥显著正向作用。 展开更多
关键词 数据要素偏向型赋能 数据要素增强型赋能 质态变迁 制造业新质生产力
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数据要素和传统要素协同配置与企业新质生产力 被引量:2
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作者 韩永彩 程丽雯 钟昌标 《工业技术经济》 北大核心 2025年第4期80-89,共10页
新质生产力强调生产要素和生产资料的有机协同,以数据要素为“催化剂”,实现新旧生产要素的创新性配置。本文利用2015~2023年中国A股上市公司数据,探究数据要素与传统要素协同促进新质生产力的机制。结果显示:数据-传统要素协同不仅具... 新质生产力强调生产要素和生产资料的有机协同,以数据要素为“催化剂”,实现新旧生产要素的创新性配置。本文利用2015~2023年中国A股上市公司数据,探究数据要素与传统要素协同促进新质生产力的机制。结果显示:数据-传统要素协同不仅具有新质生产力提升的直接效应,还具有以底层基础效能提升下的“量变”递进到上层建筑结构优化下的“质变”的间接路径;数据-劳动力协同对新质生产力的提升效应强于数据-资本协同;高新技术企业和非重污染企业提升效应更强。此结果纠正了企业发展新质生产力“一味求新”的误区,引导企业遵循比较优势,打造“以传统要素创造新型要素、以新型要素改造传统要素”的要素协同机制,为循序渐进发展新质生产力提供新思路。 展开更多
关键词 新质生产力 数据要素 资本要素 劳动力要素 协同 比较优势 渐进式发展 量变到质变
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