检索结果-南通市图书馆

偏心载荷作用下煤巷顶板托盘失效的理论与实验分析

在线全文

学校读者我要写书评

暂无评论

煤炭学报 2007年第11期32卷 1166-1169页

作者：刘少伟河南理工大学能源科学与工程学院河南焦作454003

通过现场实际调查和统计,指出了威胁巷道顶板安全的煤巷顶板锚固系统失效的原因和破坏模式.利用弹性力学的旋转球壳理论进行分析,得出了托盘在偏心载荷作用下托盘球壳与螺母接触部位材料的屈服破坏准则,提出了偏心载荷作用在托盘球壳上... 详细信息

通过现场实际调查和统计,指出了威胁巷道顶板安全的煤巷顶板锚固系统失效的原因和破坏模式.利用弹性力学的旋转球壳理论进行分析,得出了托盘在偏心载荷作用下托盘球壳与螺母接触部位材料的屈服破坏准则,提出了偏心载荷作用在托盘球壳上的水平分力是使托盘失效的主要原因.利用实验机对托盘进行偏心载荷受力模拟,得出了托盘破坏的3种破坏形式,即孔口局部失效、孔口微小破坏与盘体破裂以及孔口的不均匀下陷.根据以上研究成果,提出了设计开发偏心托盘的思路及建议.

关键词：偏心载荷托盘失效旋转球壳理论托盘破坏类型偏心托盘

Petrogenesis of late Cretaceous high Ba-Sr granodiorites,SE Lhasa block,China:implications for the reworking of juvenile crust and continental growth

在线全文

学校读者我要写书评

暂无评论

Acta Geochimica 2025年第1期44卷 86-111页

作者： Li-Hang Lin Ren-Zhi Zhu shao-Cong Lai Jiang-Feng Qin Yu Zhu shao-wei Zhao Min liu State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China Ministry of Education Key Laboratory of Western China’s Mineral Resources and Geological Engineering School of Earth Science and ResourcesChang’an UniversityXi’an 710054China

The high Ba-Sr rocks can provide significant clues about the evolution of the continent lithosphere,but their petrogenesis remains *** the Late Cretaceous high Ba–Sr granodiorites in the SE Lhasa Block could potentially provide valuable insights into the continent evolution of the Qinghai-Tibet *** U–Pb ages suggest that the granodiorites were emplaced at 87.32±0.43 ***,the high Ba–Sr granodiorites are characterized by elevated K_(2)O+Na_(2)O contents(8.18-8.73 wt%)and K_(2)O/Na_(2)O ratios(0.99-1.25,mostly>1),and belong to high-K calc-alkaline to shoshonitic *** Yonglaga granodiorites show notably high Sr(653-783 ppm)and Ba(1346-1531 ppm)contents,plus high Sr/Y(30.92-38.18)and(La/Yb)_(N)(27.7-34.7)ratios,but low Y(20.0-22.8 ppm)and Yb(1.92-2.19 ppm)contents with absence of negative Eu anomalies(δEu=0.83-0.88),all similar to typical high Ba–Sr *** variable zirconεHf(t)values of-4.58 to+12.97,elevated initial^(87)Sr/^(86)Sr isotopic ratios of 0.707254 to 0.707322 and lowεNd(t)values of-2.8 to-3.6 with decoupling from the Hf system suggest that a metasomatized mantle source included significant recycled ancient *** occurrence of such high Ba–Sr intrusions indicates previous contributions of metasomatized mantle-derived juvenile material to the continents,which imply the growth of continental crust during the Late Cretaceous in the SE *** with regional data,we infer that the underplated mafic magma provides a significant amount of heat,which leads to partial melting of the juvenile *** melting of the metasomatized mantle could produce a juvenile mafic lower crust,from which the high Ba–Sr granitoids were derived from reworking of previous mafic crust during the Late Cretaceous(ca.100-80 Ma)in the SE Lhasa.

关键词： Late Cretaceous High Ba-Sr granodiorites SE Lhasa Growth of continental crust Juvenile crust

Mechanisms of Chinese Medicine in Gastroesophageal Reflux Disease Treatment: Data Mining and Systematic Pharmacology Study

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Integrative Medicine 2023年第9期29卷 838-846页

作者： CHEN Hao-yu LI Qi ZHOU Ping-ping YANG Tian-xiao liu shao-wei ZHANG Teng-fei CUI Zhen LYU Jing-jing WANG Yan-gang Graduate School Hebei University of Chinese MedicineShijiazhuang050091China Department of Gastroenterology Hebei Province Hospital of Chinese MedicineShijiazhuang050091China Department of Gastroenterology Beijing University of Chinese Medicine Third Affiliated HospitalBeijing100029China

Objective To identify specific Chinese medicines(CMs)that may benefit patients with gastroesophageal reflux disease(GERD),and explore the action *** Domestic and foreign literature on the treatment of GERD with CMs was searched and selected from China National Knowledge Infrastructure,China Science and Technology Journal Database,Wanfang Database,and PubMed from October 1,2011 to October 1,*** from all eligible articles were extracted to establish the database of CMs for *** algorithm of data mining techniques was used to analyze the rules of herbs selection and core Chinese medicine formulas were identified.A system pharmacology approach was used to explore the action mechanism of these *** A total of 278 prescriptions for GERD were analyzed,including 192 *** of Apriori algorithm indicated that Evodiae Fructus and Coptidis Rhizoma were the highest confidence combination.A total of 32 active ingredients and 66 targets were screened for the treatment of *** analysis showed that the mechanisms of action mainly involved pathways in cancer,fluid shear stress and atherosclerosis,advanced glycation end product(AGE),the receptor for AGE signaling pathway in diabetic complications,bladder cancer,and rheumatoid *** Evodiae Fructus and Coptidis Rhizoma are the core drugs in the treatment of GERD and the potential mechanism of action of these medicines includes potential target and pathways.

关键词： gastroesophageal reflux disease Chinese medicine systematic pharmacology data mining

On equidistribution theorems for multi-sequences of holomorphic line bundles

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2025年第2期68卷 285-298页

作者： Manli liu weixiong Mai Guokuan shao Department of Mathematics South China Agricultural UniversityGuangzhou 510642China Macao Center for Mathematical Sciences Macao University of Science and TechnologyMacao 999078China School of Mathematics(Zhuhai) Sun Yat-sen UniversityZhuhai 519082China

Given several sequences of Hermitian holomorphic line bundles{(L_(kp),h_(kp))}_(p=1)^(∞),we establish the distribution of common zeros of random holomorphic sections of Lkp with respect to singular *** also study the... 详细信息

关键词： equidistribution random holomorphic section pseudo-effective line bundle current

Relationship between depth of anesthesia and effect-site concentration of propofol during induction with the target-controlled infusion technique in elderly patients

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Medical Journal 2009年第8期122卷 935-940页

作者： liu shao-hua wei wei DING Guan-nan KE Jing-dong HONG Fang-xiao TIAN Ming Department of Anesthesiology Beijing Friendship Hospital Capital Medical University Beijing 100050 China

Background There are few studies to assess whether the effect-site concentration of propofol can predict anesthetic depth during the target-controlled infusion （TCI） induction in elderly patients. This study aimed to evaluate the relationship between effect-site concentration of propofol and depth of anesthesia during the TCI induction in elderly patients. Methods Ninety patients （60-80 years） with an American Society of Anesthesiologists （ASA） physical status of 1-3, undergoing scheduled abdominal and thoracic surgery under general anesthesia were randomly allocated into one of three groups, Group S1, S2 and S3 （30 patients in each group）. The patients in Group S1 received propofol with a target plasma concentration of 4.0 pg/ml; patients in Group S2 received propofol with an initial target plasma concentrations of 2.0 IJg/ml that was raised to 4.0 pg/ml 3 minutes later; patients in Group S3 received an infused scheme of 3 steps; starting from a target plasma concentration of 2.0 pg/ml that was increased stepwised by 1 pg/ml until a target plasma concentration of 4.0 pg/ml was achieved, the interval between the two steps was 3 minutes. When an Observer＇s Assessment of Alertness/Sedation （OANS） score of 1 was achieved, remifentanil （effect-site concentration （Ce） of 4.0 ng/ml） and rocuronium 0.9 mg/kg were administered. Tracheal intubation was started 2 minutes after rocuronium injection. Changes of propofol Ce, blood pressure （BP）, heart rate （HR）, and bispectral index （BIS） were recorded. Results When an OAA/S score of 1 was achieved, Ce of propofol were （1.7±0.4） pg/ml, （1.9±0.3） pg/ml, （1.9±0.4） pg/ml and the BIS values were 64±5, 65±8, and 62±8 in Groups S1, S2 and S3. Before intubation, Ce of propofol was （2.8±0.2） pg/ml, （2.8±0.3） pg/ml, （2.7±0.3） pg/ml, and the BIS values were 48±7, 51±7, and 47±5 in Groups S1, S2 and S3. By linear regression analysis, a significant correlation between Ce of propofol and BIS values was found （r=-0.580, P 〈0.01）. Systolic blo

关键词： propofol target-controlled infusion depth of anesthesia effect-site concentration elderly patients

Decreased levels of phosphorylated synuclein in plasma are correlated with poststroke cognitive impairment

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第9期20卷 2598-2610页

作者： Yi Wang Yuning Li Yakun Gu wei Ma Yuying Guan Mengyuan Guo Qianqian shao Xunming Ji Jia liu Department of Clinical Laboratory Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijingChina Beijing Institute of Brain Disorders Laboratory of Brain DisordersMinistry of Science and TechnologyCollaborative Innovation Center for Brain DisordersBeijing Advanced Innovation Center for Big Data-based Precision MedicineCapital Medical UniversityBeijingChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina

Poststro ke cognitive impairment is a major secondary effect of ischemic stroke in many patients;however,few options are available for the early diagnosis and treatment of this *** aims of this study were to(1)determine the specific relationship between hypoxic andα-synuclein during the occur of poststroke cognitive impairment and(2)assess whether the serum phosphorylatedα-synuclein level can be used as a biomarker for poststro ke cognitive *** found that the phosphorylatedα-synuclein level was significantly increased and showed pathological aggregation around the cerebral infa rct area in a mouse model of ischemic *** addition,neuronalα-synuclein phosphorylation and aggregation were observed in the brain tissue of mice subjected to chronic hypoxia,suggesting that hypoxia is the underlying cause ofα-synuclein-mediated pathology in the brains of mice with ischemic *** phosphorylatedα-synuclein levels in patients with ischemic stroke were significantly lower than those in healt hy subjects,and were positively correlated with cognition levels in patients with ischemic ***,a decrease in serum high-density lipoprotein levels in stroke patie nts was significantly correlated with a decrease in phosphorylatedα-synuclein *** ischemic stroke mice did not show significant cognitive impairment or disrupted lipid metabolism 14 days after injury,some of them exhibited decreased cognitive function and reduced phosphorylatedα-synuclein *** together,our results suggest that serum phosphorylatedα-synuclein is a potential biomarker for poststroke cognitive impairment.

关键词： biomarker high-density lipoprotein ischemic stroke phosphorylatedα-synuclein poststroke cognitive impairment

The effects of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents:a meta-analysis

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第5期20卷 1513-1520页

作者： Xueyun shao Longfei He Yangyang liu Physical Education School Shenzhen UniversityShenzhenGuangdong ProvinceChina Shenzhen Institute of Neuroscience ShenzhenGuangdong ProvinceChina

Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase brain-derived neurotrophic factor levels in children and adolescents, the effects of specific types of exercise on brain-derived neurotrophic factor levels are still controversial. To address this issue, we used meta-analytic methods to quantitatively evaluate, analyze, and integrate relevant studies. Our goals were to formulate general conclusions regarding the use of exercise interventions, explore the physiological mechanisms by which exercise improves brain health and cognitive ability in children and adolescents, and provide a reliable foundation for follow-up research. We used the Pub Med, Web of Science, Science Direct, Springer, Wiley Online Library, weipu, Wanfang, and China National Knowledge Infrastructure databases to search for randomized controlled trials examining the influences of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents. The extracted data were analyzed using Review Manager 5.3. According to the inclusion criteria, we assessed randomized controlled trials in which the samples were mainly children and adolescents, and the outcome indicators were measured before and after the intervention. We excluded animal experiments, studies that lacked a control group, and those that did not report quantitative results. The mean difference(MD;before versus after intervention) was used to evaluate the effect of exercise on brain-derived neurotrophic factor levels in children and adolescents. Overall, 531 participants(60 children and 471 adolescents, 10.9–16.1 years) were included from 13 randomized controlled trials. Heterogeneity was evaluated using the Q statistic and I^(2) test provided by Review Manager software. The meta-analysis showed that there was no heterogeneity among the studies(P = 0.67,

关键词： adolescents brain-derived neurotrophic factor children exercise meta-analysis randomized controlled trials

Asymptotic false discovery control of the Benjamini-Hochberg procedure for pairwise comparisons

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2025年第1期68卷 223-252页

作者： weidong liu Dennis Leung Qi-Man shao School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematics and Statistics University of MelbourneVictoria 3010Australia Department of Statistics and Data Science SICMSouthern University of Science and TechnologyShenzhen 518055China

In a one-way analysis-of-variance(ANOVA) model,the number of pairwise comparisons can become large even with a moderate number of *** by this,we consider a regime with a growing number of groups and prove that,when testing pairwise comparisons,the Benjamini-Hochberg(BH) procedure can asymptotically control false discoveries,despite the fact that the involved t-statistics do not exhibit the wellknown positive dependence structure required for exact false discovery rate(FDR) *** Tukey's perspective that the difference between the means of any two groups cannot be exactly zero,our main result provides control over the directional false discovery rate and directional false discovery proportion.A key technical contribution of our work is demonstrating that the dependence among the t-statistics is sufficiently weak to establish the convergence result typically required for asymptotic FDR *** analysis does not rely on conventional assumptions such as normality,variance homogeneity,or a balanced design,thereby offering a theoretical foundation for applications in more general settings.

关键词： BH procedure directional error FDR one-way ANOVA pairwise comparison Studentized twosample t-statistic Cramer-type moderate deviation uniform law of large numbers

在线全文

学校读者我要写书评

暂无评论

多径中继传输系统网络仿真设计与实现

北京邮电大学学报 2015年第B06期38卷 92-97页

作者：刘少伟雷为民张伟付冲东北大学信息科学与工程学院沈阳110819

基于应用层中继的多径传输系统(MPTS-AR)是一种基于应用层中继的多径传输系统,通过基于用户数据报协议的中继服务器构建端到端的多径传输条件,并可支持多种业务实现多径传输.提出基于OMNeT++平台上的INET Framework实现MPTS-AR网络仿真... 详细信息

基于应用层中继的多径传输系统(MPTS-AR)是一种基于应用层中继的多径传输系统,通过基于用户数据报协议的中继服务器构建端到端的多径传输条件,并可支持多种业务实现多径传输.提出基于OMNeT++平台上的INET Framework实现MPTS-AR网络仿真的方法,包括用户代理、中继服务器和中继控制器等网络逻辑实体的二次开发方法、相关网络链路和网络拓扑的构建方法、消息定义与处理方法等;讨论了应用程序接口兼容和多业务支撑等重难点技术.最后,通过H.264业务传输实例验证了所设计MPTS-AR网络仿真的正确性和有效性.

关键词：多径传输应用层中继应用程序接口 OMNeT++ INET Framework