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Skopos:The Central Theory of Functional Approach
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作者 李永秀 《海外英语》 2012年第24期159-161,共3页
Skopos is the central theory of functional approach. In this article, firstly, it will discuss Katharina Reiss's Skopostheorie. Secondly, it will explain Has. J. Vermeer's Skopostheorie. Thirdly, it will analy... Skopos is the central theory of functional approach. In this article, firstly, it will discuss Katharina Reiss's Skopostheorie. Secondly, it will explain Has. J. Vermeer's Skopostheorie. Thirdly, it will analyze Justa Holz-Manttari and Chrisriane Nord's Skopostheorie. Finally, it will give some opinions the importance and practicality of Skopostheorie in the translating. 展开更多
关键词 Skopos central THEORY functionAL APPROACH translat
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Abnormal resting-state functional network centrality in patients with high myopia: evidence from a voxel-wise degree centrality analysis 被引量:4
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作者 Yu-Xiang Hu Jun-Rong He +7 位作者 Bo Yang Xin Huang Yu-Ping Li Fu-Qing Zhou Xiao-Xuan Xu Yu-Lin Zhong Jun Wang Xiao-Rong Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第11期1814-1820,共7页
AIM: To investigate the functional networks underlying the brain-activity changes of patients with high myopia using the voxel-wise degree centrality(DC) method.METHODS: In total, 38 patients with high myopia(HM... AIM: To investigate the functional networks underlying the brain-activity changes of patients with high myopia using the voxel-wise degree centrality(DC) method.METHODS: In total, 38 patients with high myopia(HM)(17 males and 21 females), whose binocular refractive diopter were-6.00 to-7.00 D, and 38 healthy controls(17 males and 21 females), closely matched in age, sex, and education levels, participated in the study. Spontaneous brain activities were evaluated using the voxel-wise DC method. The receiver operating characteristic curve was measured to distinguish patients with HM from healthy controls. Correlation analysis was used to explore the relationship between the observed mean DC values of the different brain areas and the behavioral performance.RESULTS: Compared with healthy controls, HM patients had significantly decreased DC values in the right inferior frontal gyrus/insula, right middle frontal gyrus, and right supramarginal/inferior parietal lobule(P〈0.05). In contrast, HM patients had significantly increased DC values in the right cerebellum posterior lobe, left precentral gyrus/postcentral gyrus, and right middle cingulate gyrus(P〈0.05). However, no relationship was found between the observed mean DC values of the different brain areas and the behavioral performance(P〉0.05).CONCLUSION: HM is associated with abnormalities in many brain regions, which may indicate the neural mechanisms of HM. The altered DC values may be used as a useful biomarker for the brain activity changes in HM patients. 展开更多
关键词 high myopia degree centrality functional magnetic resonance imaging resting state
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A central analgesic mechanism of acupuncture for migraine An ongoing functional MRI study 被引量:3
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作者 Lei Lan Yujie Gao +5 位作者 Fang Zeng Wei Qin Mingkai Dong Mailan Liu Taipin Guo Fanrong Liang 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第28期2649-2655,共7页
Shaoyang acupoints are the most frequently used in migraine treatment. However, the central anal- gesic mechanism remains poorly understood. Studies have demonstrated that single stimulus of the verum acupuncture in h... Shaoyang acupoints are the most frequently used in migraine treatment. However, the central anal- gesic mechanism remains poorly understood. Studies have demonstrated that single stimulus of the verum acupuncture in healthy subjects can induce significant connectivity or activity changes in pain- related central networks compared with sham acupuncture. However, these findings are not indicative of the central analgesic mechanism of acupuncture at Shaoyang acupoints. Thus, we recruited 100 migraine sufferers and randomly assigned them into five groups: Shaoyang uncommon acupoint, Shaoyang common acupoint, Yangming uncommon acupoint, non-acupoint control, and blank control groups. Subjects were subjected to evaluation of curative effects and functional MRI prior to and after 10 and 20 acupuncture treatments. All subjects were diagnosed by physicians and enrolled following clinical physical examination. Subjects were observed during 1-4 weeks after inclusion. At the fifth week, the first clinical evaluation and resting functional MRI were conducted. The Shaoyang uncom- mon acupoint, Shaoyang common acupoint, Yangming uncommon acupoint, and non-acupoint control grousp then were treated with acupuncture, five times per week, 20 times in total over 4 weeks. The second and third clinical evaluations and resting functional MRI screenings were conducted following 10 and 20 acupuncture treatments. The blank control group was observed during the 5 to 8 week pe- riod, followed by clinical evaluation and resting functional MRI. The aim of this study was to examine changes in brain functional activity and central networks in subjects with migraine undergoing acu- puncture at Shaoyang uncommon acupoints. This study provides a further explanation of the central analgesic mechanism by which acupuncture at Shaoyang acupoints treats migraine, 展开更多
关键词 neural regeneration acupuncture and moxibustion MIGRAINE ACUPUNCTURE analgesia central re-sponse functional MRI sessions of acupuncture continuous central activity study design grants-supported paper NEUROREGENERATION
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THE SPHERICAL FUNCTIONS AND THE CENTRAL LIMIT THEOREM ON SU(2,2)/S(U(2)×U(2))
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作者 杨乔华 张钦 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期867-874,共8页
Let G = SU(2, 2), K = S(U(2) × U(2)), and for l ∈ Z, let {Tl}l∈z be a one-dimensional K-type and let El be the line bundle over G/K associated to Tl. It is shown that the Tl-spherical function on G is g... Let G = SU(2, 2), K = S(U(2) × U(2)), and for l ∈ Z, let {Tl}l∈z be a one-dimensional K-type and let El be the line bundle over G/K associated to Tl. It is shown that the Tl-spherical function on G is given by the hypergeometric functions of several variables. By applying this result, a central limit theorem for the space G/K is obtained. 展开更多
关键词 Spherical function central limit theorem hypergeometric function
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Centrality Measures Based on Matrix Functions
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作者 Lembris Laanyuni Njotto 《Open Journal of Discrete Mathematics》 2018年第4期79-115,共37页
Network is considered naturally as a wide range of different contexts, such as biological systems, social relationships as well as various technological scenarios. Investigation of the dynamic phenomena taking place i... Network is considered naturally as a wide range of different contexts, such as biological systems, social relationships as well as various technological scenarios. Investigation of the dynamic phenomena taking place in the network, determination of the structure of the network and community and description of the interactions between various elements of the network are the key issues in network analysis. One of the huge network structure challenges is the identification of the node(s) with an outstanding structural position within the network. The popular method for doing this is to calculate a measure of centrality. We examine node centrality measures such as degree, closeness, eigenvector, Katz and subgraph centrality for undirected networks. We show how the Katz centrality can be turned into degree and eigenvector centrality by considering limiting cases. Some existing centrality measures are linked to matrix functions. We extend this idea and examine the centrality measures based on general matrix functions and in particular, the logarithmic, cosine, sine, and hyperbolic functions. We also explore the concept of generalised Katz centrality. Various experiments are conducted for different networks generated by using random graph models. The results show that the logarithmic function in particular has potential as a centrality measure. Similar results were obtained for real-world networks. 展开更多
关键词 GRAPH centralITY Measures MATRIX functionS Kendall Correlation COEFFICIENT RANDOM GRAPH Models
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The Control of Population Growth Is the Function of the Central Government 
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《China Population Today》 1994年第2期2-3,1,共3页
Mr.Jiang Zcmin,Gencral-Seerctary of the Cen-tral Committee of the Chincse Communist Party and.Chairman of the People's Republic of China,in a rC-ccnt spcech cm phasized that the family planning pro-gramme should b... Mr.Jiang Zcmin,Gencral-Seerctary of the Cen-tral Committee of the Chincse Communist Party and.Chairman of the People's Republic of China,in a rC-ccnt spcech cm phasized that the family planning pro-gramme should be strictly and effectively im plemented in 1994,a year of crucial importance for promoting re-form and opening and thc drive lowards.modernization.To makc continucd contributions to the sociocconomic development in the country,we must fulfil the plan for controlling population growth..The spcech was delivcred at the anua!National Fo-rum on Family Planning Work convened jointly by the Party's Central Committcc and the Statc Council. 展开更多
关键词 The Control of Population Growth Is the function of the central Government
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Central swallowing in normal adults using functional magnetic resonance imaging
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作者 Shasha Li Cheng Luo +2 位作者 Chengqi He Qiyong Gong Dong Zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第4期258-264,共7页
BACKGROUND: While brain-imaging studies in healthy adults have indicated that multiple cortical regions are involved in swallowing, these functional imaging techniques have not been extensively applied to the complet... BACKGROUND: While brain-imaging studies in healthy adults have indicated that multiple cortical regions are involved in swallowing, these functional imaging techniques have not been extensively applied to the complete understand neurophysiology of swallowing in China. A full understanding of normal swallowing neurophysiology is important for improving functional outcomes for dysphagia due to neurologic disorders or damage with increasing age. Thus the interpretations of the functional contributions of various brain areas in swallowing should be scientifically researched. OBJECTIVE: To identify the activation and characteristic of swallowing center in healthy adults using functional magnetic resonance imaging. DESIGN, TIME AND SETTING: An uncontrolled neuroimaging study was performed at the Outpatient Clinic, Department of Radiology, West China Hospital of Sichuan University between March and November 2008. PARTICIPANTS: Ten healthy right-handed volunteers, aged over 20 years with a mean age of (34.2 + 8.1) years, a range of 25-45 years and including five males and five females participated. A medical history was obtained from all potential subjects and all subjects were free of systemic diseases and neurological disorders. METHODS: The healthy volunteers were examined with event-related functional magnetic resonance imaging of blood oxygenation level-dependent while laryngeal swallow-related movements were recorded. Subjects were scanned during voluntary saliva swallowing and water bolus swallowing activation tasks. Data was processed using the General Linear Model. A voxel by voxel group comparison was performed using random effect analysis. Any cluster with a corrected P 〈 0.05 for spatial extent was considered significant. MAIN OUTCOME MEASURES: The cerebral cortical activation maps of voluntary swallowing of saliva and swallowing of water bolus in healthy adults were observed. RESULTS: A multifocal cortical representation of swallowing was in the precentral gyrus, postcentral gyrus, insula, anterior cingulate gyrus, thalamus, basal ganglia and cerebellum, in a bilateral and asymmetrical manner, predominantly on the left hemisphere in the volunteers (P 〈 0.05). CONCLUSION: Activation of the cortex during normal swallowing tasks may be functionally linked to basal nuclei, thalamus, and cerebellum, greatly appearing in the left hemisphere. 展开更多
关键词 SWALLOWING central swallowing blood oxygenation level-dependent functional magnetic resonance imaging
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Ecological Function Value of Tropical Forests in the Central Mountainous Areas of Hainan Island
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作者 Jing GAO Zuguang ZHOU 《Asian Agricultural Research》 2013年第11期103-105,108,共4页
The integrated value of the ecological function of tropical forests in the central mountainous areas of Hainan Island was 33.064 8 billion yuan/a in 2010(soil improvement,soil consolidation,soil nutrient maintenance,w... The integrated value of the ecological function of tropical forests in the central mountainous areas of Hainan Island was 33.064 8 billion yuan/a in 2010(soil improvement,soil consolidation,soil nutrient maintenance,water storage and moisture regulation,water purification,carbon sequestration,oxygen releasing,air purification,biodiversity conservation,eco-tourism),equivalent to 16.1%of GDP in Hainan Province this year(205.212 billion yuan).The tropical forests in the central mountainous areas of Hainan Island make great contribution to Hainan Island's ecology,and play an important role in maintaining the stability of the ecological environment in Hainan Island.Through the understanding of major ecological function value of tropical forests,it is necessary to make people cherish the tropical forests in the central ecological function conservation areas of Hainan Province,and spontaneously throw themselves into the ecological environment protection and construction,to promote the rapid and sustainable development of construction in Hainan Province as an international tourism island. 展开更多
关键词 central mountainous areas TROPICAL FORESTS Ecologi
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Structural neuroimaging and neuropsychological correlates of a single case of focal central pontine myelinolysis: Intact memory function with decreased intellectual and motor functions
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作者 Myriah K. Mulvogue Thomas P. Robinson +1 位作者 Mohammad S. Ijaz Simon M. McCrea 《World Journal of Neuroscience》 2012年第4期192-199,共8页
We report on the case of middle-aged right-handed woman with central pontine myelinolysis (CPM) revealed by high resolution structural T2-weighted FLAIR MRI imaging. There was a general flattening of Wechsler Adult In... We report on the case of middle-aged right-handed woman with central pontine myelinolysis (CPM) revealed by high resolution structural T2-weighted FLAIR MRI imaging. There was a general flattening of Wechsler Adult Intelligence Scale—Fourth Edition subtest scores which were 1 standard deviation below expected values. In contrast Wechsler Memory Scale—Fourth Edition visual and auditory memory scores remained within the normal range. Verbal working memory appeared mildly impaired while nonverbal working memory was not. Scores on the Advanced Clinical Solution’s Social Perception battery were all in the normal range as were academic skills measured by the Wide Range Achievement Test—Fourth Edition. Performance was impaired on the Delis-Kaplan Executive Function System’s counterpart of the Trail-Making Test: Part B. Similarly, on the Draw-A-Person Test there was a discrepancy in that our patient’s standard score was 76 compared to her estimated premorbid FSIQ in the average range. She also displayed bilateral motor coordination slowing on the Finger Tapping task collectively suggesting damage to pontine motor tracts. The Minnesota Multiphasic Personality Inventory—Second Edition—Restructured Form profile was consistent with a diagnosis of severe anxiety and depression perhaps due to damage to serotoninergic neural tracts originating within the central pons. Finally, the patient displayed severe sleep disturbances and other signs of reticular activating formation injury. CPM may constitute a unique means of studying reversible subcortical lesions in the central pons in otherwise healthy subjects with benign illness. To our knowledge this is among the first patients with CPM without the usual risk factors for the disorder and who was otherwise healthy. Knowledge of the etiology and neuropsychology of such patients might aid in understanding the interaction of the fronto-ponto-cerebellar tracts in executive functions and motor programming. 展开更多
关键词 central PONTINE MYELINOLYSIS NEUROPSYCHOLOGY T2-Weighted Structural MRI FLAIRImaging Motor functions SUBCORTICAL Signs Fronto-Ponto-Cerebellar function
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Monitoring recent changes in snow cover in Central Asia using improved MODIS snow-cover products 被引量:8
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作者 LIU Jinping ZHANG Wanchang LIU Tie 《Journal of Arid Land》 SCIE CSCD 2017年第5期763-777,共15页
Snow cover plays an important role in the fields of climatology and cryospheric science. Remotely-sensed data have been proven to be effective in monitoring snow covers. Improved methods to process the 8-day snow-cove... Snow cover plays an important role in the fields of climatology and cryospheric science. Remotely-sensed data have been proven to be effective in monitoring snow covers. Improved methods to process the 8-day snow-cover products derived from MODIS Terra/Aqua data can dramatically increase the data quality and reduce noise. A five-step algorithm for removing cloud effects was designed to improve the quality of MODIS snow products, and the overall accuracy of the MODIS snow data without cloud(defined as cloud-free snow-cover dataset) was enhanced by more than 90% based on direct and indirect validation methods. The snow-cover frequency(SCF) and snow-cover rate(SCR) of Central Asia were analyzed from 2000 to 2015 using trend analysis and empirical orthogonal functions(EOFs). Over the plain regions, the SCF displayed a significant north-south declining trend with a rate of 0.03 per degree of latitude, and the SCR showed a similar north-south gradient. In the mountainous areas, the SCF significantly increased with altitude by 0.12 per kilometer. Within the study area, the SCF in 65% of the study area experienced an increasing trend, but only 4.3% of the SCF-increasing pixels passed a significance test. The remaining 35% of the area underwent a decreasing trend of SCF, but only 5.2% of the SCF-decreasing pixels passed a significance test. For the entire Central Asia, the inter-annual variations of snow-cover presented a slight and insignificant increase trend from 2000 to 2015. However, the change trends of snow cover are different between the plain and mountainous regions. That is, the annual mean SCR in the plain areas displayed an increasing trend, but a decreasing trend was found in the mountainous areas. 展开更多
关键词 snow-cover MODIS cloud-removing empirical orthogonal function central Asia
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Erosive esophagitis associated with metabolic syndrome,impaired liver function, and dyslipidemia 被引量:3
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作者 Song-Seng Loke Kuender D Yang +1 位作者 Kuang-Den Chen Jung-Fu Chen 《World Journal of Gastroenterology》 SCIE CAS 2013年第35期5883-5888,共6页
AIM:To investigate whether erosive esophagitis is correlated with metabolic syndrome and its components,abnormal liver function,and lipoprotein profiles.METHODS:We conducted a cross-sectional,case control study of sub... AIM:To investigate whether erosive esophagitis is correlated with metabolic syndrome and its components,abnormal liver function,and lipoprotein profiles.METHODS:We conducted a cross-sectional,case control study of subjects who underwent upper endoscopy during a health examination at the Health Management and Evaluation Center of a tertiary medical care facility located in Southern Taiwan.Metabolic syndrome components,body mass index(BMI),liver function,dyslipidemia,and cardiovascular risk factors,as defined by the ratio of total cholesterol to high-density lipoprotein cholesterol(HDL-C),and the ratio of low-density lipoprotein cholesterol to HDL-C were compared betweenindividuals with and without erosive esophagitis.Risk factors for erosive esophagitis were evaluated by multivariate logistic regression.RESULTS:Erosive esophagitis was diagnosed in 507of 5015 subjects who were individually age and sex matched to 507 esophagitis-free control subjects.In patients with erosive esophagitis,BMI,waist circumference,blood pressure,fasting plasma glucose,triglyceride levels,aspartate aminotransferase,alanine aminotransferase,the ratio of total cholesterol to HDL-C,and the ratio of low-density lipoprotein cholesterol to HDL-C were significantly higher and HDL-C was significantly lower compared to patients without erosive esophagitis(all P<0.05).In a multivariate analysis,central obesity(OR=1.38;95%CI:1.0-1.86),hypertension(OR=1.35;95%CI:1.04-1.76),hypertriglyceridemia(OR=1.34;95%CI:1.02-1.76),cardiovascular risk factors as defined by a ratio of total cholesterol to HDL-C>5(OR=1.45;95%CI:1.06-1.97),and aspartate aminotransferase(OR=1.59;95%CI:1.08-2.34)were significantly associated with erosive esophagitis.CONCLUSION:Metabolic syndrome,impaired liver function,and a higher ratio of total cholesterol to HDL-C were associated with erosive esophagitis. 展开更多
关键词 EROSIVE ESOPHAGITIS Metabolic syndrome central obesity ABNORMAL liver function DYSLIPIDEMIA
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Monitoring Brain and Spinal Cord Metabolism and Function 被引量:1
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作者 Pierre Pandin Marie Renard +2 位作者 Alessia Bianchini Philippe Desjardin Luc Van Obbergh 《Open Journal of Anesthesiology》 2014年第6期131-152,共22页
Monitoring the metabolism and function of the central nervous system not only is an old idea but also is a topic that is of increasing interest to the technological evolution. Beside the optimization of cerebral and s... Monitoring the metabolism and function of the central nervous system not only is an old idea but also is a topic that is of increasing interest to the technological evolution. Beside the optimization of cerebral and spinal cord perfusion and the preservation of vasoreactivity to ensure the viability of cerebral tissues and structures, we want to know more and more about the real intimate situation of these organs in real time at the patient’s bedside. To this end, several tracks have been explored during the two last decades, leading to the development of numerous concepts and the conception of various monitoring systems. One of the main problems is to characterize the respective strong points and weaknesses of those ones and to conclude regarding their individual relevance and value in current clinical practice. It is more and more clear that the combination of different categories of monitoring is a way to try to find the most valuable technological compromise, to increase the chance of prediction or of early detection of intercurrent deleterious events corresponding to the concept of multimodality. The intraoperative period and the intensive care goals and targets are appreciably different. This is the reason for the attempt to define different and distinct sets of goals and targets for the intraoperative anesthetic setting and for the intensive care unit. 展开更多
关键词 BRAIN central Nervous System MONITORING METABOLISM function
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Connectivity differences between adult male and female patients with attention deficit hyperactivity disorder according to resting-state functional MRI 被引量:7
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作者 Bo-yong Park Hyunjin Park 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第1期119-125,共7页
Attention deficit hyperactivity disorder(ADHD) is a pervasive psychiatric disorder that affects both children and adults. Adult male and female patients with ADHD are differentially affected, but few studies have ex... Attention deficit hyperactivity disorder(ADHD) is a pervasive psychiatric disorder that affects both children and adults. Adult male and female patients with ADHD are differentially affected, but few studies have explored the differences. The purpose of this study was to quantify differences between adult male and female patients with ADHD based on neuroimaging and connectivity analysis. Resting-state functional magnetic resonance imaging scans were obtained and preprocessed in 82 patients. Group-wise differences between male and female patients were quantified using degree centrality for different brain regions. The medial-, middle-, and inferior-frontal gyrus, superior parietal lobule, precuneus, supramarginal gyrus, superior- and middle-temporal gyrus, middle occipital gyrus, and cuneus were identified as regions with significant group-wise differences. The identified regions were correlated with clinical scores reflecting depression and anxiety and significant correlations were found. Adult ADHD patients exhibit different levels of depression and anxiety depending on sex, and our study provides insight into how changes in brain circuitry might differentially impact male and female ADHD patients. 展开更多
关键词 neural regeneration connectivity attention deficit hyperactivity disorder sex difference functional magnetic resonance imaging depression anxiety network analysis degree centrality diagnostic and statistical manual score
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Major ozonated autohemotherapy promotes the recovery of upper limb motor function in patients with acute cerebral infarction 被引量:23
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作者 Xiaona Wu Zhensheng Li +4 位作者 Xiaoyan Liu Haiyan Peng Yongjun Huang Gaoquan Luo Kairun Peng 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第5期461-468,共8页
Major ozonated autohemotherapy is classically used in treating ischemic disorder of the lower limbs In the present study, we performed major ozonated autohemotherapy treatment in patients with acute cerebral infarctio... Major ozonated autohemotherapy is classically used in treating ischemic disorder of the lower limbs In the present study, we performed major ozonated autohemotherapy treatment in patients with acute cerebral infarction, and assessed outcomes according to the U.S. National Institutes of Health Stroke Score, Modified Rankin Scale, and transcranial magnetic stimulation motor-evoked potential. Compared with the control group, the clinical total effective rate and the cortical potential rise rate of the upper limbs were significantly higher, the central motor conduction time of upper limb was significantly shorter, and the upper limb motor-evoked potential amplitude was significantly increased, in the ozone group. In the ozone group, the National Institutes of Health Stroke Score was positively correlated with the central motor conduction time and the motor-evoked potential amplitude of the upper limb. Central motor conduction time and motor-evoked potential amplitude of the upper limb may be effective indicators of motor-evoked potentials to assess upper limb motor function in cerebral infarct patients. Furthermore, major ozonated autohemotherapy may promote motor function recovery of the upper limb in patients with acute cerebral infarction. 展开更多
关键词 neural regeneration clinical practice ozone cerebral infarction evoked potential motor upper limbs upper limb paralysis motor function central motor conduction time amplitude National Institutes of Health Stroke Score grants-supported paper photographs-containing paper neuroregenertion
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ASYMPTOTIC NORMALITY OF KERNEL ESTIMATES OF A DENSITY FUNCTION UNDER ASSOCIATION DEPENDENCE
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作者 林正炎 《Acta Mathematica Scientia》 SCIE CSCD 2003年第3期345-350,共6页
Let {Xn, n≥1} be a strictly stationary sequence of random variables, which are either associated or negatively associated, f(.) be their common density. In this paper, the author shows a central limit theorem for a k... Let {Xn, n≥1} be a strictly stationary sequence of random variables, which are either associated or negatively associated, f(.) be their common density. In this paper, the author shows a central limit theorem for a kernel estimate of f(.) under certain regular conditions. 展开更多
关键词 Associated random variables negatively associated random variables kernel estimate of a density function central limit theorem
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通信网络抗震薄弱单元评价和识别方法
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作者 毛晨曦 王卓 +2 位作者 龚牛栋 王涛 孙国良 《自然灾害学报》 北大核心 2025年第5期129-140,共12页
为有效提升通信系统的抗震安全性,该文针对通信网络抗震薄弱单元的评价和识别方法进行研究。首先,提出基于基站掉站率的通信系统抗震能力评价方法。然后,对于抗震能力不满足要求的通信系统,综合考虑网络单元的拓扑重要度和抗震能力,提... 为有效提升通信系统的抗震安全性,该文针对通信网络抗震薄弱单元的评价和识别方法进行研究。首先,提出基于基站掉站率的通信系统抗震能力评价方法。然后,对于抗震能力不满足要求的通信系统,综合考虑网络单元的拓扑重要度和抗震能力,提出一种评价网络单元抗震薄弱程度的加权平均指标W(v),给出指标界限值W_(L)的确定方法,据此识别出网络中的抗震薄弱单元。最后,以一个虚拟城市通信网络的整体抗震能力评价和抗震薄弱单元识别为例,验证了该文方法的有效性,并比较分析了基于3种不同加权策略的W(v)指标识别抗震薄弱单元的效率。分析结果表明,W(v)指标可以有效识别出通信网络中的抗震薄弱单元。此外,倾向于优先筛选高拓扑重要度的加权策略3,在薄弱节点识别效率上表现得更为突出。 展开更多
关键词 通信网络 抗震能力评价 抗震薄弱单元识别 介数中心性 功能易损性
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Optimization of the Impeller Geometry for an Automotive Torque Converter Using Response Surface Methodology and Desirability Function
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作者 Xiang Chen Jie Chen 《Open Journal of Applied Sciences》 2020年第7期455-475,共21页
Response surface methodology (RSM) based on desirability function approach (DFA) is applied to obtain an optimal design of the impeller geometry for an automotive torque converter. <span style="font-family:Ver... Response surface methodology (RSM) based on desirability function approach (DFA) is applied to obtain an optimal design of the impeller geometry for an automotive torque converter. <span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">The relative importance of six design parameters including impeller blade number, blade thickness, bias angle, scroll angle, inlet angle and exit angle is investigated using orthogonal design approach. </span></span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">The impeller inlet angle, exit angle and bias angle </span><span style="font-family:Verdana;">are found to exert the greatest influence on the overall performance of a torque converter, with two flow area factors being considered, namely 17% and 20%. Then, RSM together with central composite design (CCD) method is used to in-depth evaluate the interaction effect of the three key parameters on converter performance. The results demonstrate that </span><span style="font-family:Verdana;">impeller exit angle has the strongest impact on peak efficiency</span><span style="font-family:Verdana;">, with larger angles yielding the most favorable results. The stall torque ratio maximization is attainable with the increase of impeller bias angle and inlet angle together with smaller exit angle. In the end, </span><span style="font-family:Verdana;">an optimized design for the impeller geometry is obtained with stall torque ratio and peak efficiency increased by 1.62% and 1.1%, respectively.</span><span style="font-family:Verdana;"> The new optimization method can be used as a reference for performance enhancement in the design process of impeller geometry for an automotive torque converter.</span></span></span></span> 展开更多
关键词 Automotive Torque Converter Response Surface Methodology Desirability function Approach central Composite Design OPTIMIZATION
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鲁中山地侧柏人工林生态服务功能价值及影响因素
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作者 王静 梁燕 +3 位作者 曲永赟 葛忠强 王清华 杜振宇 《河北林业科技》 2025年第3期9-16,共8页
以鲁中山地侧柏人工林为对象,采用国家标准《森林生态系统服务功能评估规范》(GB/T 38582—2020)的评估指标体系和方法,计算了保育土壤、林木养分固持、固碳释氧、净化大气环境、生物多样性保护、林木产品供给6类生态服务功能价值。结... 以鲁中山地侧柏人工林为对象,采用国家标准《森林生态系统服务功能评估规范》(GB/T 38582—2020)的评估指标体系和方法,计算了保育土壤、林木养分固持、固碳释氧、净化大气环境、生物多样性保护、林木产品供给6类生态服务功能价值。结果显示:23个供试侧柏人工林的生态服务功能的平均价值为52412元/(hm^(2)·a);在6类生态服务功能中,固碳释氧功能的价值最大,林木养分固持功能价值最小,分别占总价值的55%和3%;胸径、树高、材积等13个指标对侧柏人工林的生态服务功能价值产生了显著影响,林分生长状况与生态服务功能价值呈现正相关,按对生态总价值贡献度大小排序,前6位指标依次为:生物量>树高>胸径>材积>海拔>有效钾,生长因子对侧柏人工林生态总价值的综合影响要明显高于土壤因子和立地环境因子。 展开更多
关键词 侧柏 生态服务功能 鲁中山地
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A Note on the Almost Sure Central Limit Theorem in the Joint Version for the Maxima and Partial Sums of Certain Stationary Gaussian Sequences
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作者 Yuanfang Wang Qunying Wu 《Applied Mathematics》 2014年第10期1598-1608,共11页
Considering a sequence of standardized stationary Gaussian random variables, a universal result in the almost sure central limit theorem for maxima and partial sum is established. Our result generalizes and improves t... Considering a sequence of standardized stationary Gaussian random variables, a universal result in the almost sure central limit theorem for maxima and partial sum is established. Our result generalizes and improves that on the almost sure central limit theory previously obtained by Marcin Dudzinski [1]. Our result reaches the optimal form. 展开更多
关键词 ALMOST Sure central Limit Theorem STATIONARY GAUSSIAN Sequence Slowly Varying functions at INFINITY
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