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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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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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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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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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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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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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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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THE NUMERICAL SOLUTION OF A SINGULARLY PERTURBED PROBLEM FOR QUASILINEAR PARABOLIC DIFFERENTIAL EQUATION
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作者 苏煜城 沈全 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第6期497-506,共10页
We consider the numerical solution of a singularly perturbed problem for the quasilinear parabolic differential equation, and construct a linear three-level finite difference scheme on a nonuniform grid. The uniform c... We consider the numerical solution of a singularly perturbed problem for the quasilinear parabolic differential equation, and construct a linear three-level finite difference scheme on a nonuniform grid. The uniform convergence in the sense of discrete L2 norm is proved and numerical examples are presented. 展开更多
关键词 quasilinear parabolic difTerential equation singular perturbation linear three-level difference scheme uniform convergence
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战略差异度、技术创新与企业全要素生产率——来自A股上市公司的经验证据 被引量:2
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作者 盛明泉 龙卉卉 鲍群 《河南师范大学学报(哲学社会科学版)》 北大核心 2024年第2期30-38,F0002,共10页
战略差异度对企业的影响是学术界关注的重要问题,而企业能否通过加大战略差异度进而提升全要素生产率为研究企业战略决策方面提供了不同的切入点。采用2009-2020年沪深A股上市公司的数据样本,实证检验了战略差异度对企业全要素生产率的... 战略差异度对企业的影响是学术界关注的重要问题,而企业能否通过加大战略差异度进而提升全要素生产率为研究企业战略决策方面提供了不同的切入点。采用2009-2020年沪深A股上市公司的数据样本,实证检验了战略差异度对企业全要素生产率的影响。研究结果表明,战略差异度对企业全要素生产率起到显著的正向作用,技术创新在战略差异度影响企业全要素生产率的传导路径上存在中介效应。进一步研究发现,高行业竞争水平、高信息透明度和低融资约束企业的战略差异度越大对全要素生产率的正向作用越显著。研究丰富了全要素生产率的相关文献,并为其提供了研究的新视角。同时有助于企业利益相关者理解战略决策的经济后果,对指导和促进企业进行战略变革及获取竞争优势提供理论参考。 展开更多
关键词 战略差异度 全要素生产率 技术创新 行业竞争水平 信息透明度
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中原城市群文化软实力综合评价及空间分异研究 被引量:1
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作者 李晗 马芳芳 丁志伟 《地域研究与开发》 北大核心 2024年第2期63-70,共8页
基于文化吸引力、文化展示力、文化传播力、文化创新力、文化事业投入力和文旅融合力6个维度构建文化软实力评价指标体系,运用空间分类、核密度分析、空间自相关等方法,分析中原城市群文化软实力的空间特征并解析其影响因素。结果表明:... 基于文化吸引力、文化展示力、文化传播力、文化创新力、文化事业投入力和文旅融合力6个维度构建文化软实力评价指标体系,运用空间分类、核密度分析、空间自相关等方法,分析中原城市群文化软实力的空间特征并解析其影响因素。结果表明:(1)从综合实力差异看,高、较高文化软实力城市数量少且主要分布在核心区,中等实力城市仅有3个,半数城市为低和较低实力。空间上具有明显的东西差异,西半壁呈现以郑汴为引领的中心外围格局,东半壁则表现为亳州、阜阳引领的极化特征,且在东西半壁之间形成聊城至驻马店的低值连绵带。(2)从分维度空间差异看,文化吸引力子系统、文化展示力子系统与综合实力格局类似,而文化事业投入力子系统呈现“西北高、东南低”的格局。此外,文化传播力子系统、文化创新力子系统呈现与前3个子系统完全不同的格局,表现为以郑汴为核心的低值包围高值的分布结构。(3)从空间集聚和关联看,中原城市群分别围绕郑州和亳州形成了“一主一副”的双核集聚态势,且主核区附近形成了显著的高-高集聚群。其中,文化吸引力子系统与综合实力的集聚格局基本一致,文化展示力子系统的集聚在郑州减弱而在亳州得到加强,文化传播力子系统和文化创新力子系统仅在中部形成集聚核心,文旅融合力子系统则在综合格局的基础上在东南部形成两个集聚核心。(4)从影响因素看,市区GDP对城市文化软实力的影响最强,第三产业增加值次之,交通设施、科教文卫单位数和城镇化率的影响作用不明显。 展开更多
关键词 文化软实力 水平评价 空间差异 影响因素 中原城市群
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济南市典型区夏季VOCs分布特征及臭氧生成机制 被引量:2
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作者 张桂芹 樊联欢 +4 位作者 韩立钊 周梅 魏征 孙秀芹 魏小锋 《环境化学》 CAS CSCD 北大核心 2024年第1期297-310,共14页
基于2020年6—8月济南市石化区、市区和南部山区VOCs以及臭氧和气态污染物等在线监测数据,结合气象因素分析了各典型区夏季VOCs污染特征,并通过计算臭氧生成潜势(OFP)和MCM模型模拟分析了不同区域不同污染等级VOCs对臭氧生成的影响,采用... 基于2020年6—8月济南市石化区、市区和南部山区VOCs以及臭氧和气态污染物等在线监测数据,结合气象因素分析了各典型区夏季VOCs污染特征,并通过计算臭氧生成潜势(OFP)和MCM模型模拟分析了不同区域不同污染等级VOCs对臭氧生成的影响,采用PMF模型对市区夏季VOCs进行了来源解析研究.结果表明,石化区VOCs浓度(158.29μg·m^(-3))明显高于市区(47.71μg·m^(-3))和南部山区(24.65μg·m^(-3)),VOCs中均以烷烃占比最大,其次为芳香烃,3个区域VOCs浓度均随污染等级升高而升高;不同污染等级下均为石化区OFP(743.7—1474.9μg·m^(-3))大于市区(156.9—378.1μg·m^(-3))和南部山区(113.4—168.7μg·m^(-3)),3个区域均是芳香烃OFP占比最大,其次为烯烃,说明芳香烃和烯烃类VOCs对臭氧生成的贡献最大,其中OFP贡献最大的单体为间/对-二甲苯;MCM模拟结果表明石化区O_(3)净生成速率(33.51×10^(-9)·h^(-1))最高,其次为市区(22.97×10^(-9)·h^(-1))和南部山区(3.91×10^(-9)·h^(-1));石化区的1-戊烯、甲苯、异戊二烯、间-乙基甲苯和邻二甲苯,市区的1-丁烯、间/对-二甲苯和顺式-2-丁烯,南部山区的顺式-2-丁烯、异戊二烯、反式-2-丁烯相对增量反应活性(RIR)较大,对臭氧生成的影响较为明显.PMF模型解析结果表明济南市区夏季燃烧源、移动源和餐饮油烟源对VOCs贡献较大. 展开更多
关键词 VOCs分布特征 不同污染等级 臭氧生成机制 夏季 PMF
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中国数字经济发展水平时空演变及区域差异分析 被引量:1
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作者 王彦庆 薛静娴 符建华 《商业经济》 2024年第5期1-5,共5页
数字经济作为国民经济的核心增长极之一,正在成为促进经济发展的新动能。构建数字经济发展水平指标体系,运用熵值法对2014—2020年中国省际数字经济发展水平进行测度,在此基础上进一步探究中国数字经济发展的分布动态和区域差异。研究... 数字经济作为国民经济的核心增长极之一,正在成为促进经济发展的新动能。构建数字经济发展水平指标体系,运用熵值法对2014—2020年中国省际数字经济发展水平进行测度,在此基础上进一步探究中国数字经济发展的分布动态和区域差异。研究结果表明:与2014年相比,2020年中国数字经济发展水平整体有所提升,分区域看,东部地区数字经济发展水平呈波动下降趋势,中西部地区呈上升趋势且差距较小;空间分布上,中国数字经济呈现东高西低的发展格局,而且在发展过程中逐步形成多极分化状态;东、中、西地区数字经济发展的相对差异呈不断缩小趋势,并且区域内差异是造成数字经济发展存在差异的主要原因。 展开更多
关键词 数字经济 发展水平 时空演变 区域差异
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中国新质生产力的发展水平和演进趋势 被引量:1
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作者 高怡冰 任沛阳 陈钰鑫 《科技管理研究》 2024年第14期47-58,共12页
新质生产力的测算是研究新质生产力发展水平的基础,但当前关于新质生产力的评价指标体系和测度方法尚处于探索阶段。鉴于新质生产力是质和量的统一、能力和效率的统一、现实性和可比性的统一,依据生产力理论,结合高质量发展的现实要求,... 新质生产力的测算是研究新质生产力发展水平的基础,但当前关于新质生产力的评价指标体系和测度方法尚处于探索阶段。鉴于新质生产力是质和量的统一、能力和效率的统一、现实性和可比性的统一,依据生产力理论,结合高质量发展的现实要求,以及新质生产力在科技创新、要素提升、生产组织等方面的特征,系统分析新质生产力的本质要求、构成要素、实现途径、培育载体和支撑环境,在此基础上构建包括技术、要素、数字、产业和环境五维度的指标体系,对中国30个省份2022—2022年的新质生产力发展水平进行测度,并分析其发展格局和演进趋势。结果表明:30个省份新质生产力发展水平增长较快,但区域差异、经济带差异、城市差异明显;要素生产力保持较高水平,数字生产力和创新生产力加快发展,绿色生产力和产业生产力成为发展的短板。其中,从区域格局来看,东部高于30个省份的平均水平,中西部和东北地区低于30个省份的平均水平;从经济格局来看,长江经济带最高,其次是泛珠三角,而丝绸之路经济带低于30个省份的平均水平;从城市格局来看,三大城市群从高到低依次为珠三角、长三角、京津冀,并且均高于30个省份的平均水平。 展开更多
关键词 新质生产力 生产力发展水平 指标体系 发展差异 生产力测度
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水位差法模拟波浪荷载作用下大直径圆筒稳定性离心模型试验研究
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作者 任国峰 关云飞 +2 位作者 周春儿 顾行文 徐光明 《岩土工程学报》 EI CAS CSCD 北大核心 2024年第S01期27-31,共5页
某人工岛护岸工程采用大直径圆筒结构,结构直径和高度尺寸较大,工程所处位置波浪条件恶劣。采用水位差法等效模拟波浪荷载,开展波浪荷载作用下大圆筒施工期稳定特性离心模型试验研究,结果表明,在25 a一遇波吸力荷载作用下,筒体位移模式... 某人工岛护岸工程采用大直径圆筒结构,结构直径和高度尺寸较大,工程所处位置波浪条件恶劣。采用水位差法等效模拟波浪荷载,开展波浪荷载作用下大圆筒施工期稳定特性离心模型试验研究,结果表明,在25 a一遇波吸力荷载作用下,筒体位移模式近似平移,侧向位移量约353 mm,筒顶沉降约为187 mm,施工阶段钢圆筒整体稳定;筒壁环向拉应力均值约为90 MPa,处于钢圆筒材料允许应力范围内;筒壁海侧土压力值随水位差增大至峰值后趋于稳定,表明筒体与周围邻近土体之间没有新的相对位移趋势,大直径钢圆筒护岸结构在波浪荷载作用下是稳定安全的。 展开更多
关键词 大直径圆筒结构 水位差法 离心模型试验 机理 稳定性
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血清IL-6水平检测在原发免疫性血小板减少症患者预后疗效评估的临床意义
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作者 马强 刘力源 《宁夏医学杂志》 CAS 2024年第4期318-321,共4页
目的本研究旨在探索血清白介素6(IL-6)水平对初诊原发免疫性血小板减少症患者预后疗效的影响。方法回顾性分析70例符合原发免疫性血小板减少症诊断的初诊患者,收集患者的临床资料,并对血清IL-6水平、血小板计数、出血评分进行测定。根... 目的本研究旨在探索血清白介素6(IL-6)水平对初诊原发免疫性血小板减少症患者预后疗效的影响。方法回顾性分析70例符合原发免疫性血小板减少症诊断的初诊患者,收集患者的临床资料,并对血清IL-6水平、血小板计数、出血评分进行测定。根据血清IL-6测量结果,将患者分为低水平组(IL-6≤25 pg/mL)、中水平组(2535 pg/mL)。应用标准化治疗并随访3个月,收集并分析患者实验室检查、疗效评价等指标。采用多元Cox回归分析IL-6水平与患者预后指标的相关性。结果治疗前,不同IL-6水平组患者的血小板计数和出血评分差异无统计学意义(P>0.05)。治疗3个月后,IL-6高水平组的血小板计数更低,出血评分更高(P<0.05);IL-6低水平组的预后疗效最好(P<0.05)。患者的年龄、病程、治疗后的出血评分、血小板计数和疗效评价与IL-6水平呈相关关系(P<0.05)。结论本研究表明血清IL-6与原发免疫性血小板减少症患者的预后存在相关性,高IL-6水平可能提示原发免疫性血小板减少症预后较差。IL-6水平有望成为早期评估原发免疫性血小板减少症患者预后的潜在生物标志物,但仍需进一步的研究和验证。 展开更多
关键词 原发免疫性血小板减少症 白介素-6 相关性
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