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Mapping and measuring urban-rural inequalities in accessibility to social infrastructures 被引量:1
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作者 Chenmeng Guo Weiqi Zhou +1 位作者 Chuanbao Jing Dawa Zhaxi 《Geography and Sustainability》 CSCD 2024年第1期41-51,共11页
Equal access to social infrastructures is a fundamental prerequisite for sustainable development,but has long been a great challenge worldwide.Previous studies have primarily focused on the accessibility to social inf... Equal access to social infrastructures is a fundamental prerequisite for sustainable development,but has long been a great challenge worldwide.Previous studies have primarily focused on the accessibility to social infras-tructures in urban areas across various scales,with less attention to rural areas,where inequality can be more severe.Particularly,few have investigated the disparities of accessibility to social infrastructures between urban and rural areas.Here,using the Changsha-Zhuzhou-Xiangtan urban agglomeration,China,as an example,we investigated the inequality of accessibility in both urban and rural areas,and further compared the urban-rural difference.Accessibility was measured by travel time of residents to infrastructures.We selected four types of social infrastructures including supermarkets,bus stops,primary schools,and health care,which were funda-mentally important to both urban and rural residents.We found large disparities in accessibility between urban and rural areas,ranging from 20 min to 2 h.Rural residents had to spend one to two more hours to bus stops than urban residents,and 20 min more to the other three types of infrastructures.Furthermore,accessibility to multiple infrastructures showed greater urban-rural differences.Rural residents in more than half of the towns had no access to any infrastructure within 15 min,while more than 60%of the urban residents could access to all infrastructures within 15 min.Our results revealed quantitative accessibility gap between urban and rural areas and underscored the necessity of social infrastructures planning to address such disparities. 展开更多
关键词 ACCESSIBILITY Social infrastructures urban-rural difference INEQUALITY Regional sustainability
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Geriatric nursing competence of clinical nursing staff at different hospital levels in Chongqing,China:A cross-sectional study
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作者 Jinfeng Long Yaling Li +10 位作者 Wenping Chen Xiaoqun Wu Rongjuan Fu Li Dong Yi Huang Daibi Yi Zhihui Xu Yan Cheng Qun Tan Li Zhang Fu Ding 《International Journal of Nursing Sciences》 CSCD 2024年第4期439-446,I0002,共9页
Objectives:This study aimed to survey the geriatric nursing competencies of clinical nursing staff in Chongqing City,China,and provide suggestions to enhance these competencies.Methods:This study was conducted in 204 ... Objectives:This study aimed to survey the geriatric nursing competencies of clinical nursing staff in Chongqing City,China,and provide suggestions to enhance these competencies.Methods:This study was conducted in 204 hospitals in Southwest China from December 24,2022 to January 7,2023.The“Geriatric Nursing Competence of Clinical Nurse Investigation Tool”was used to explore factors that influence geriatric nurses’competencies via stratified sampling.The survey was conducted by distributing and collecting questionnaires through the online platform Wenjuanxing.Results:A total of 10,692 nurses answered the questionnaires.Of these questionnaires,9,442 were valid.The total geriatric nursing competence score of the clinical nursing staff was 2.29±0.81,the secondary hospital score was 2.23±0.78,and the tertiary hospital’s overall mean score was 2.33±0.83.The factors that influenced secondary hospitals included the department of medicine,age of nurses and total length of career(P<0.05).The factors that influenced tertiary hospitals included the department of medicine,age of nurses,nurses’professional title,and geriatric practical advanced nurses’certification(P<0.05).Conclusions:Geriatric nursing competence among clinical nursing staff is imbalanced at a lower-middle level and is influenced by various factors.Thefindings highlight the need for further clinical training in geriatric nursing.The training of geriatric nurses should focus on necessary clinical skills and on preparing them to adequately manage comprehensive geriatric syndromes. 展开更多
关键词 Aged Clinical nursing different hospital levels Geriatric nursing competence Geriatric advanced practice nurses
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Study of Short Column Behavior Originated from the Level Difference on Sloping Lots during Earthquake (Special Case: Reinforced Concrete Buildings) 被引量:1
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作者 Keyvan Ramin Foroud Mehrabpour 《Open Journal of Civil Engineering》 2014年第1期23-34,共12页
The disorders originated from architectural design in buildings, show in different forms. One of them is the level difference originated from lot’s slope which affects structures through short column phenomenon. The ... The disorders originated from architectural design in buildings, show in different forms. One of them is the level difference originated from lot’s slope which affects structures through short column phenomenon. The great stiffness of short columns enables them to absorb large amounts of structural energy. Inattention of some manuals and regulations such as Earthquake regulations to this phenomenon necessitates paying further attention to it. On this basis, the present study employed experimental modeling and numerical modeling for a four-story reinforced concrete building that involves the analysis of simple 2-D frames of varying floor heights and varying number of bays using a very popular software tool STAAD Pro on both a sloping and a flat lot. Also Sap2000 software had been used to show that the displacement of floors is greater for a flat lot building than a sloping lot building. However, the increase in shear was found to be quite greater in short columns compared to common ones and an enormous moment should be tolerated by sloping lot structures. The greater stiffness of the structure was also revealed by non-linear static (Push-Over) analysis. According to the results, short column are required to have more resistant sections and are suggested to be reinforced with more bars. In addition, more steel should be used as stirrups than as longitudinal bars. Also for existing structures, shear capacity of short columns should be retrofitted by FRP, Steel Jacket or other materials. 展开更多
关键词 SHORT COLUMN Reinforced Concrete level difference SLOPE EARTHQUAKE
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Simulation of the water level influence on the difference within the water-tube tiltmeter in Shuangyang Lake 被引量:1
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作者 Chong Yue Chuncheng Tang +5 位作者 Wei Yan Xiaodong Pan Xueme Li Yuwen Tan Zongfeng Zhang Tianlong Yu 《Earthquake Research Advances》 CSCD 2021年第2期33-39,共7页
This article analyzes the relationship between the water level and the water-tube tilting in Shuangyang lake,based on the differential deformation features reflected by the NS and EW components of the water-tube tiltm... This article analyzes the relationship between the water level and the water-tube tilting in Shuangyang lake,based on the differential deformation features reflected by the NS and EW components of the water-tube tiltmeter.The results show a good spatiotemporal consistency between the variation of water level and the NS tilt component,which is considered to be affected by the magnitude and duration of the water level variation in Shuangyang Lake.The article uses Landsat remote sensing image data to extract the water boundary of Shuan-gyang Lake,and takes advantage of the finite element numerical simulation method to build three-dimensional models for different geological structural conditions of the Shuangyang seismostation.The simulation results show that when the underground medium is granite,the effect of water level variation on the vertical displacement of the surface is non-directional.With a 50-m soil layer in Model 2,the simulated NS tilt variation is equivalent to the actual observed water-tube tiltmeter NS component when the water level variation is 0.44 m and 0.8m.When the variation of water level reaches 2.0m,the simulation result of the NS component is 79.6 ms,which is slightly larger than the observed result of 60.32 ms.However,the simulation results show that the variation of the EW component is significantly smaller than that of the NS one.Due to the fact that the Shuan-gyang lake is long in the NS direction and short in the EW direction,the existence of the soil layer tends to generate ground deformation along the NS direction in the vicinity of the lake after the increase of water level,thereby resulting in the difference of the ground deformation in the two directions. 展开更多
关键词 Water-tube tiltmeter at shuangyang seismostation Water level of shuangyang lake Finite element method difference of the ground deformation
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A new tracking error detection method using amplitude difference detection for signal waveform modulation multi-level discs 被引量:1
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作者 严明铭 裴京 潘龙法 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期319-323,共5页
The sub-land/sub-pit affects the characteristic of the tracking error signal which is generated by the conventional differential phase detection (DPD) method in the signal waveform modulation multi-level (SWML) re... The sub-land/sub-pit affects the characteristic of the tracking error signal which is generated by the conventional differential phase detection (DPD) method in the signal waveform modulation multi-level (SWML) read-only disc. To solve this problem, this paper proposes a new tracking error detection method using amplitude difference. Based on the diffraction theory, the amplitude difference is proportional to the tracking error and is feasible to be used for obtaining the off-track information. The experimental system of the amplitude difference detection method is developed. The experimental results show that the tracking error signal derived from the new method has better performance in uniformity and signal-to-noise ratio than that derived from the conventional DPD method in the SWML read-only disc. 展开更多
关键词 signal waveform modulation multi-level technology tracking error amplitude difference
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Analysis of the Differences in Expenditure Levels of Participants at the 2014 Asian Basketball League in Ho Chi Minh City
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作者 Lam Quang Thanh Nguyen Hoang Mirth Thuan Nguyen Thanh Tu 《Journal of Sports Science》 2016年第6期377-382,共6页
Research focuses on studying the economic impacts of 2014 Asian Basketball League in Ho Chi Minh City (hereinaiter referred as ABL 2014) with respect to direct expenditure of all types of participants, including org... Research focuses on studying the economic impacts of 2014 Asian Basketball League in Ho Chi Minh City (hereinaiter referred as ABL 2014) with respect to direct expenditure of all types of participants, including organizers, coaches/athletes, journalists/communicators, audiences, etc. Research was implemented with 920 subjects, including 48 members of the organizing committee, 56 coaches/athletes, 800 audiences and 16 members of journal and media teams. 展开更多
关键词 differenceS level of expenditure participants.
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Effects of Different Nitrogen Fertilizer Levels on Lodging and Yield of Rice 被引量:5
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作者 杨和川 武立权 +3 位作者 韩新峰 邵辉 柯健 王荣富 《Agricultural Science & Technology》 CAS 2012年第7期1456-1459,共4页
[Objective] This study aimed to investigate the effects of different fertilizer levels on lodging and yield of rice. [Method] A total of four treatments were designed and applied with 6, 9, 12 and 15 kg of nitrogen fe... [Objective] This study aimed to investigate the effects of different fertilizer levels on lodging and yield of rice. [Method] A total of four treatments were designed and applied with 6, 9, 12 and 15 kg of nitrogen fertilizer, respectively. After seedling transplanting, the biological characteristics of rice at different growth stages in each treatment and the biological and economic characteristics of rice after lodging were determined for statistical analysis. [Result] Application with 15 kg of nitrogen fertilizer had significant promotion effect on the increase of rice yield; compared with the control (6 kg of nitrogen fertilizer), rice yield in three experimental treatments (9, 12 and 15 kg of nitrogen fertilizer, respectively) increased by 50.74%, 89.11% and 94.48%, respectively; lodging-resistance mechanical strengths of the three experimental treatments were 103.97%, 132.01% and 89.83% of the control, respectively; rice lodging resistance of treatment C (12 kg of nitrogen fertilizer) was the strongest, with the highest yield. [Conclusion] This study provides reference data and technical support for the rational fertilization of rice production. 展开更多
关键词 differENT nitrogen fertilizer levelS RICE Fresh weight YIELD LODGING
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Analysis on Influential Factors of Peasants' Willingness to Exit Homestead in Regions with Different Economy Development Levels——Taihe Village,Chaohu County-Level City,and Ancang Village,Taihu County as Examples 被引量:1
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作者 刘逦 杨子生 杨青 《Agricultural Science & Technology》 CAS 2016年第5期1268-1270,共3页
The research concluded peasants' willingness on homestead exiting and influential factors by questionnaire survey and interviewing in two villages with varied levels of economic development in Anhui Province.Comparis... The research concluded peasants' willingness on homestead exiting and influential factors by questionnaire survey and interviewing in two villages with varied levels of economic development in Anhui Province.Comparisons were performed on subjective factors and objective factors were explored by Logistic regression.The results showed that both of education background and homestead use have positive correlation with peasants' willingness on homestead exit;the number of family members has negative effects on peasants in advanced village but the number of migrant workers or members living in cities has positive effects;the area of homestead has positive effects on peasants in underdeveloped village.Therefore,the emphasis should be varied on homestead exit upon village economy and it is necessary to reinforce homestead exit promotion at improving immigrants' reception work,social security,employment,and education. 展开更多
关键词 Homestead exit different economic development levels Peasants' willingness Influential factors
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Influence of the Different Level Ammonium on NRA and GSA in Sugar Beet(Vulgaris L.)
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作者 ZHAOYue WEIZi-min +1 位作者 MAFeng-ming WANGLian-jun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2003年第1期88-91,共4页
Ammonium nitrogen inhibited NR activity in sugar beet,NR activity was lower in endogenous substrate after ammonium nitrogen was used,and the correlation between NR activity and ammonium nitrogen levels was negative.Bu... Ammonium nitrogen inhibited NR activity in sugar beet,NR activity was lower in endogenous substrate after ammonium nitrogen was used,and the correlation between NR activity and ammonium nitrogen levels was negative.But NR activity raised with the ammonium nitrogen levels raising in exogenous.Ammonium nitrogen prompted GS activity:the correlation between GS activity and ammonium nitrogen was positive,GS activity raised with ammonium nitrogen levels raising,GS activity of roots and leaves had same change trend in sugar beet in the whole growth duration after ammonium nitrogen was used,but GS activity in roots was higher than that in leaves. 展开更多
关键词 sugar beet different level ammonium NRA GSA
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A new finite difference scheme for a dissipative cubic nonlinear Schrdinger equation 被引量:2
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作者 张荣培 蔚喜军 赵国忠 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期27-32,共6页
This paper considers the one-dimensional dissipative cubic nonlinear SchrSdinger equation with zero Dirichlet boundary conditions on a bounded domain. The equation is discretized in time by a linear implicit three-lev... This paper considers the one-dimensional dissipative cubic nonlinear SchrSdinger equation with zero Dirichlet boundary conditions on a bounded domain. The equation is discretized in time by a linear implicit three-level central difference scheme, which has analogous discrete conservation laws of charge and energy. The convergence with two orders and the stability of the scheme are analysed using a priori estimates. Numerical tests show that the three-level scheme is more efficient. 展开更多
关键词 dissipative cubic nonlinear Schr5dinger equation three-level finite difference convergence and stability analysis
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THE RELATIONSHIP BETWEEN THE ERYTHROCYTE POLYAMINE LEVELS AND THE DIFFERENT TYPES OF LEUKEMIA
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作者 缪金明 欧阳仁荣 潘瑞彭 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1991年第1期69-72,共4页
In a study on erythrocyte polyamine levels in 20 leukemia patients and 18 healthy individuals, following results were obtained. Putrescine(Pu) in ery-throcytes was nearly undetectable but in 2 AMoL patients; Spermidin... In a study on erythrocyte polyamine levels in 20 leukemia patients and 18 healthy individuals, following results were obtained. Putrescine(Pu) in ery-throcytes was nearly undetectable but in 2 AMoL patients; Spermidine(Spd) level in ALL was higher than the control volue (P<0.05), in AML (M1, M2) and APL the Spd level was in the range of control group (P>0.1), while that in AMoL and AMMoL was considerably lower as compared to control (P< 0.001); Spermine (Spm) level in all types of leukemia was increased (P<0.001); Spd/Spm ratio was significantly decreased, showing 1.525 in control group, 0.938 in ALL (P<0.025), 0.779 in AML (M1, M2) P< 0.01), 0.319 in APL (P<0.001) and 0.296 in AMoL & AMMoL (P<0.001), and the differences between the Spd/Spm ratio in AMoL and AMMoL and in ALL were noted (P<0.05). These results suggested that determination of erythrocyte polyamines in leukemia patients may be helpful in diagnosis, differential diagnosis and prognosis. 展开更多
关键词 THE RELATIONSHIP BETWEEN THE ERYTHROCYTE POLYAMINE levelS AND THE differENT TYPES OF LEUKEMIA
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Comparison of the level of thrombus precursor protein in blood plasma between patients with acute cerebral infarction and healthy persons at different time
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作者 Chenghua Xiao Peng Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第3期258-260,共3页
BACKGROUND: Thrombus precursor protein (TpP) is the index of thrombus activity level, and it is also early referencing index in detecting thrombus diseases. OBJECTIVE: To dynamically observe the changes of TpP lev... BACKGROUND: Thrombus precursor protein (TpP) is the index of thrombus activity level, and it is also early referencing index in detecting thrombus diseases. OBJECTIVE: To dynamically observe the changes of TpP level in blood plasma of patients with acute cerebral infarction at different time after onset, and to compare the differences of plasma TpP level between patients with acute cerebral infarction and healthy persons who received health examination. DESIGN: Controlled observation SETTING: Department of Neurology, Affiliated Hospital of Xuzhou Medical College PARTICIPANTS: Totally 58 patients with acute cerebral infarction who received the treatment in the Department of Neurology, Affiliated Hospital of Xuzhou Medical College between September 2004 and March 2005 were recruited in this study. They all met the diagnostic criteria revised by the 4^th National Conference of Cerebrovascular Disorders in 1995 and were diagnosed by clinical and skull CT and (or) MRI examinations. The patients included 33 male and 25 female aged from 36 to 87 years. Time to onset 〈 6 hours, 6 to 11 hours, 12 to 23 hours, 24 to 48 hours and 〉 48 hours were found in 10,11,14,10 and 13 patients respectively. Another 51 persons who homeochronously received the health body examination in our hospital were recruited, including 34 male and 17 female, aged 38 to 85 years, serving as control group. Patients with cardio-cerebrovascualr diseases or liver and kidney diseases were excluded. All the involved subjects were informed of the detected items. METHODS: About 4 mL venous blood was respectively taken from patients admitted to the hospital within 6 hours, 6 toll hours, 12 to 23 hours, 24 to 48 hours and more then 48 hours after onset, and healthy persons when receiving health examination. The level of TpP in blood plasma was measured with enzymelinked immunosorbent assay. MAIN OUTCOME MEASURES: ① Comparison of the level of plasma TpP between patients and controls;② Comparison of the level of plasma TpP of patients with acute cerebral infarction at different time after onset. RESULTS: Totally 58 patients with acute cerebral infarction and 51 persons who received health examination participated in the result analysis. ①Comparison of plasma TpP level between patients and controls: The plasma TpP level of patients with acute cerebral infarction was significantly higher than that of control group [(16.12±3.28)vs (5.38±1.36) mg/L, t= 20.993, P〈 0.01 ]. ② Comparison of plasma TpP level of patients with acute cerebral infarction at different time after onset: The level of plasma TpP was (12.06±3.06) mg/L within 6 hours, (15.11±3.42) mg/L at 6 to 11 hours, (20.63±4.05) mg/L at 12 to 23 hours, (16.15±3.50) mg/L at 24 to 48 hours and (11.88±3.11) mg/L at more than 48 hours after onset. It increased from the 6^th hour, reached the peak at the 12^th to 23^rd hours, maintained at very high level at the 48= hour and then gradually decreased and recovered to the level within 6 hours after onset. The level of plasma TpP of patients with acute cerebral infarction was signiticantly higher at the 12^th to 23^rd hours after onset and the 24^th to 48^th hours after onset than within 6 hours after onset (t = 13.385, P 〈 0.05). CONCLUSION: ①The level of plasma TpP of patients with acute cerebral infarction is significantly higher than that of persons who received health examination.② Plasma TpP levels of patients with acute cerebral infarction change in wave manner at the different time after onset. 展开更多
关键词 Comparison of the level of thrombus precursor protein in blood plasma between patients with acute cerebral infarction and healthy persons at different time time
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Research on the Digital Economy's Impact on China's Economic Growth:Based on the Variations in Urbanization Levels Across China's Eastern,Central,and Western Regions and Sectoral Heterogeneity
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作者 Qiu Jin Yan Hong 《Contemporary Social Sciences》 2024年第3期27-44,共18页
This paper uses inter-provincial panel data from 2011 to 2017,a linear regression model,and a threshold model to conduct empirical analyses of the impact of the digital economy on China's overall economic growth a... This paper uses inter-provincial panel data from 2011 to 2017,a linear regression model,and a threshold model to conduct empirical analyses of the impact of the digital economy on China's overall economic growth and the three main sectors of industry.The paper then investigates the impact and effects the digital economy has had on the economic growth of the three main sectors of industry in China's eastern,central,and western regions.Finally,the paper investigates the most significant differences among the various regions and the threshold effects of urbanization levels on the relationship between the digital economy and economic growth.The findings indicate a significantly positive correlation between the digital economy and regional economic growth.Moreover,geographical factors notably influence this correlation.The digital economy exerts a positive effect on all sectors of industry.It may not substantially impact industrial development in regions with highly developed infrastructure.Regarding the other regions,the digital economy exhibits varying degrees of impact due to the differences in the specific indicators.The conclusion drawn by the threshold model is that the magnitude of the threshold effect correlates with geographic factors.No threshold effect was observed in the eastern region,while the threshold effect occurred in the central region when the urbanization levels for the provinces were below 0.6645.Similarly,the threshold effect was noted in the western region when the urbanization level was below 0.3931.Considering all of this,the study also offers policy recommendations that will help balance the regional development of digital economies,accelerate the digital transformation of traditional industries,enhance digital infrastructure construction,refine the formulation and implementation of data policy,and establish relevant incentive mechanisms. 展开更多
关键词 digital economy economic growth regional differences urbanization level threshold models
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Clinical Application of Sex Hormone in Different Physiological Periods in the Diagnosis of Infertility Patients
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作者 Jianhong Nong Daxian Tan +4 位作者 Arshad Mehmood Tingchao Wang Xin Liu Li Deng Bowen Wei 《Natural Science》 2024年第6期102-110,共9页
Background: Infertility is characterized by the inability to conceive after a year of regular unprotected intercourse. Aims: This study aimed to investigate the diagnostic value of sex hormone levels during different ... Background: Infertility is characterized by the inability to conceive after a year of regular unprotected intercourse. Aims: This study aimed to investigate the diagnostic value of sex hormone levels during different physiological periods in the diagnosis of infertility patients. Methods: From December 2019 to May 2021, a total of 93 infertility patients were admitted and selected as the observation group. Among them, 31 cases were in the follicular stage, 31 cases in the ovulation stage, and 31 cases in the luteal stage. Ninety-three healthy women for fertility evaluation due to male infertility were selected as the control group. The control group included 31 women in the follicular phase, 31 women in the ovulatory phase, and 31 women in the luteal phase. The levels of sex hormones (prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E2), testosterone (T), and progesterone (P)) during different physiological phases were compared between the observation and control groups. Results: The follicular phase showed no significant difference in LH levels between the observation group and the control group. The observation group showed higher levels of PRL and P compared to the control group, while the levels of FSH, E2, and T were lower in the observation group compared to the control group. The ovulation phase showed no significant difference in PRL levels between the two groups. The observation group showed lower levels of LH, FSH, E2, T, and P compared to the control group. The luteal phase showed no statistical difference in E2 levels between the two groups. The observation group showed higher levels of PRL, LH, and FSH compared to the control group, while the levels of T and P were lower in the observation group compared to the control group. Conclusion: Infertile women show variations in hormone levels compared to the normal levels during the follicular phase, ovulatory phase, and luteal phase. 展开更多
关键词 different Periods Sex Hormone level Detection INFERTILITY Auxiliary Diagnosis
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Relation between Economic Development Level and Resource and Environment Carrying Capacity of Central Area of Yunnan Province Based on Decoupling Analysis 被引量:4
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作者 程超 童绍玉 +2 位作者 彭海英 闫少凯 刘玲 《Agricultural Science & Technology》 CAS 2015年第12期2829-2832,共4页
Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling ... Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling degree and temporal changes of economic development level and resource and environment carrying ca- pacity in the central area of Yunnan Province. Results indicated that (i) the economic development level and resource and environment carrying capacity in the central area of Yunnan Province mainly experienced strong decoupling, weak decoupling, and ex- pansive negative coupling, and in general it was strong decoupling, and it took on re- verse "N" in temporal changes. (ii) Change rate of economic development level in the central area of Yunnan Province was greater than zero, but the amplitude of change was not large, while the change rate of resource and environment carrying capacity was negative in 2007-2008, and it was positive in the rest years; from 2007, it took on gradual expansion trend, and scissors difference gradually increased after experi- encing reverse "V" change. (iii) The strong decoupling was the main situation and it reached the peak value in T5 period and T6 pedod. 展开更多
关键词 The central area of Yunnan Province Economic development level Re- source and environment carrying capacity Decoupling analysis Scissors difference
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基于Level Set方法的西夏字轮廓提取 被引量:2
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作者 柳长青 《中文信息学报》 CSCD 北大核心 2009年第4期71-76,共6页
随着国内外对西夏研究的不断深入,收藏于世界各地的大批西夏古籍文献通过影印方式陆续出版。如何将这些西夏古籍文献进行数字化、文本化则有着极其重要的意义。首先利用平滑和细化算法对西夏影印文献进行了预处理,然后利用Level set方... 随着国内外对西夏研究的不断深入,收藏于世界各地的大批西夏古籍文献通过影印方式陆续出版。如何将这些西夏古籍文献进行数字化、文本化则有着极其重要的意义。首先利用平滑和细化算法对西夏影印文献进行了预处理,然后利用Level set方法对影印文献中的西夏字进行了轮廓提取。Level Set演化函数在空间方向上采用了四阶紧致差分逼近式离散,计算过程中加入了窄带算法及全局优化方法。实验表明,算法在不增加计算时间的基础上可以得到较精确的西夏字轮廓。 展开更多
关键词 人工智能 模式识别 西夏文信息处理 level SET方法 西夏字 轮廓提取 紧致差分
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基于Level Set方法的人脸轮廓提取
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作者 柳长青 田振夫 《计算机工程与设计》 CSCD 北大核心 2008年第12期3179-3181,3184,共4页
人脸轮廓提取在诸如安全检查、保安管理、交通电子监控、机器人研究等方面有着十分重要的应用价值。先利用图像背景差分法快速检测出人脸的初始矩形轮廓线,然后采用LevelSet方法对视频图像进行人脸轮廓提取,Level Set演化函数空间方向... 人脸轮廓提取在诸如安全检查、保安管理、交通电子监控、机器人研究等方面有着十分重要的应用价值。先利用图像背景差分法快速检测出人脸的初始矩形轮廓线,然后采用LevelSet方法对视频图像进行人脸轮廓提取,Level Set演化函数空间方向上采用四阶紧致差分逼近式离散,计算过程中加入了窄带算法和全局优化方法。数值实验结果表明,该算法在不增加计算时间的基础上,可以检测出模糊或离散的边界,并得到精确的人脸轮廓线。 展开更多
关键词 levelSet方法 轮廓提取 紧致差分 计算机视觉 图像处理
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Exploring the urban-rural development differences and influencing factors in the Huang-Huai-Hai Plain of China 被引量:3
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作者 CHENG Mingyang LI Linna ZHOU Yang 《Journal of Geographical Sciences》 SCIE CSCD 2020年第10期1603-1616,共14页
Uneven urban and rural development is one of the main reasons for the decline of the countryside.This imbalance could be measured by the urban-rural difference index(URDI).Existing studies on urban-rural differences h... Uneven urban and rural development is one of the main reasons for the decline of the countryside.This imbalance could be measured by the urban-rural difference index(URDI).Existing studies on urban-rural differences have focused on single dimension between urban and rural areas,and lack a systematic multi-dimensional measurement.Based on the construction of an index system and model for measuring urban-rural differences,this study took the Huang-Huai-Hai Plain(HHHP)as the study area,explores the spatial pattern of urban-rural differences in the area,and used geographical weighted regression models to identify the factors affecting urban-rural development differences.Results show that the mean value of URDI in the HHHP was 0.295,and the URDI in its western region was higher than that in the east.The average URDI was relatively high in the western counties along the Beijing–Guangzhou Railway.The low level of urban-rural'population-land-industry'development in the HHHP is an important reason for the small differences between urban and rural areas.Improvements in road transportation infrastructure have led to an increase in the urban-rural development gap.However,the driving force of the road network on urban development is greater than that on rural areas.The role of county economic agglomeration is gaining strength.In the process of rapid economic development,more attention should be paid to the development of the rural economy and the overall revitalization of the countryside.The equivalent allocation of social service facilities is an effective way to solve the problem of urban-rural imbalance.Further analysis demonstrated that terrain factors have relatively little influence on the URDI.This study provides a new perspective and measurement method for understanding the integration of urban and rural development,and provides a useful reference for guiding the urban-rural integration development and the rural revitalization. 展开更多
关键词 urban-rural difference index(URDI) population-land-industry urban-rural relationship rural revitalization Huang-Huai-Hai Plain(HHHP) China
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Effect of Water Level Fluctuations on Wintering Goose Abundance in Poyang Lake Wetlands of China 被引量:11
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作者 XIA Shaoxia LIU Yu +4 位作者 CHEN Bin JIA Yifei ZHANG Huan LIU Guanhua YU Xiubo 《Chinese Geographical Science》 SCIE CSCD 2017年第2期248-258,共11页
The Poyang Lake is a Ramsar site and is the important over-wintering site for migratory waterbirds along the East Asian-Australasian Fly way. Examining the effects of water level fluctuations on waterbird abundance an... The Poyang Lake is a Ramsar site and is the important over-wintering site for migratory waterbirds along the East Asian-Australasian Fly way. Examining the effects of water level fluctuations on waterbird abundance and analyzing the influencing mechanism is critical to waterbird protection in the context of hydrological alteration. In this study, the effect of water level regime on wintering goose abundance was examined and the influencing mechanism was interpreted. Synchronous waterbirds survey data, hydro- logical data, Moderate Resolution Imaging Spectroradiometer-Normalized Difference Vegetation Index (MODIS-NDVI) data and habi- tat data derived from Landsat TNUETM data and HJ/CCD data were combined. The satellite-derived Green Wave Index (GWI) based on MODIS-NDVI dataset was applied to detect changes in goose food resources. It was found that habitat size and vegetation conditions are key factors determining goose abundance. Geese numbers were positively correlated with habitat area, while intermediate range of vegetation productivity might benefit the goose abundance. Water level affects goose abundance by changing available habitat areas and vegetation conditions. We suggested that matching hydrological regime and exposed meadows time to wintering geese dynamics was crucial in the Poyang Lake wetlands. Our study could provide sound scientific information for hydrological management in the context of waterbird conservation. 展开更多
关键词 water level fluctuation wintering geese Normalized difference Vegetation Index (NDVI) Green Wave Index (GWI) waterbird habitat
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Limb symmetry index in competitive alpine ski racers:Reference values and injury risk identification according to age-related performance levels 被引量:6
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作者 Lisa Steidl-Müller Carolin Hildebrandt +2 位作者 Erich Müiller Christian Fink Christian Raschner 《Journal of Sport and Health Science》 SCIE 2018年第4期405-415,共11页
Purpose: The aims of this study were to assess differences of limb symmetry index (LSI) in strength- and coordination-related tasks between high-level, competitive, noninjured ski racers of different age-related pe... Purpose: The aims of this study were to assess differences of limb symmetry index (LSI) in strength- and coordination-related tasks between high-level, competitive, noninjured ski racers of different age-related performance levels and to prospectively assess limb differences as a possible risk factor for traumatic and overuse injury in youth ski racers. Methods: The study (Study 1) included 285 high-level competitive ski racers (125 females, 160 males) of 3 age-related performance levels and based on the school system: 95 youth (10-14 years, secondary modem school), 107 adolescent (15-19 years, grammar school), and 83 elite athletes (20-34 years). To investigate the second aim (Study 2), 67 of the 95 youth athletes were included and any traumatic or overuse injuries were prospectively recorded over 2 seasons. All athletes performed 4 unilateral tests (strength related: one-leg counter movement jump (OL-CMJ) and one-leg isometric/isokinetic press strength test (OL-ILS); coordination related: one-leg stability test (OL-ST) and one-leg speedy jump test (OL-SJ)). The LSI was calculated by dividing the dominant leg by the nondominant leg and multiplying by 100. Kruskal-Wallis H tests and binary logistic regression analyses were conducted. Results: There were significant differences between the LSI of the 3 age-related performance-level groups only in the strength-related tests: the OL-CMJ (X^2(2, 285) = 9.09; p = 0.01) and the OL-ILS (X^2(2,285) = 14.79; p 〈 0.01). The LSI for OL-ILS was found to be a significant risk factor for traumatic injury in youth ski racers (Wald = 7.08; p 〈 0.01). No significant risk factors were found for overuse injuries. Conclusion: Younger athletes display slightly greater LSI values only in the strength-related tests. The cut-off value of limb differences of 〈 10% for return to sport decisions seems to be appropriate for elite athletes, but for youth and adolescent athletes it has to be critically discussed. It seems to be necessary to define thresholds based on specific performance tasks (strength vs. coordination related) rather than on generalizations, and age-related performance levels must be considered. Limb differences in unilateral leg extension strength represent a significant injury risk factor in youth ski racers.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Age-related performance levels Alpine ski racing Injury risk Limb differences Youth athletes
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