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New strategies for asymmetric photocatalysis: asymmetric organocatalytic/photoredox relay catalysis for efficient synthesis of polycyclic compounds containing vicinal amino alcohols

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Science China Chemistry 2024年第3期67卷 945-952页

作者： Jia-Lu Zhang wen-bo he Xiu-Qin Hu Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Veterinary Etiological Biology College of Veterinary MedicineLanzhou UniversityLanzhou Veterinary Research InstituteChinese Academy of Agricultural SciencesLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China

An asymmetric catalytic strategy in photocatalysis utilizing a chirality-induced approach through an organocatalytic/photoredox relay catalysis strategy is successfully achieved for the rapid construction of polycyclic compounds containing vicinal amino alcohols in a one-pot protocol. This methodology facilitates the efficient synthesis of diverse substituted polycyclic tetrahydroquinoline and benzofuran-derived vicinal amino alcohols, each containing five consecutive chiral centers, with high yields,excellent diastereoselectivities and enantioselectivities(up to 95% yield, >20:1 dr and 98% ee), under mild reaction conditions driven by sequential bifunctional squaramide organocatalyst-catalyzed [4+2] annulation and photocatalyst-catalyzed ketyl radical addition cyclization reaction process. Furthermore, investigations into the stereoselectivity mechanism and high-resolution mass spectrometry(HRMS) experiments on free radical trapping have provided evidence for elucidating the detailed mechanism of chirality-induced processes and chiral intermediate conversions in this procedure.

关键词： enantioselective photocatalysis asymmetric organocatalytic/photocatalysis relay catalysis five consecutive chiral centers chirality-induced strategy chirality vicinal amino alcohols

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Prevalence of white matter hyperintensities increases with age

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Neural Regeneration Research 2018年第12期13卷 2141-2146页

作者： Feng-Juan Zhuang Yan Chen wen-bo he Zhi-You Cai Department of Neurology Renmin Hospital Hubei University of Medicine Department of Neurology Chongqing General Hospital University of Chinese Academy of Sciences

White matter hyperintensities（WMHs） that arise with age and/or atherosclerosis constitute a heterogeneous disorder in the white matter of the brain. However, the relationship between age-related risk factors and the prevalence of WMHs is still obscure. More clinical data is needed to confirm the relationship between age and the prevalence of WMHs. We collected 836 patients, who were treated in the Renmin Hospital, Hubei University of Medicine, China from January 2015 to February 2016, for a case-controlled retrospective analysis. According to T2-weighted magnetic resonance imaging results, all patients were divided into a WMHs group（n = 333） and a non-WMHs group（n = 503）. The WMHs group contained 159 males and 174 females. The prevalence of WMHs increased with age and was associated with age-related risk factors, such as cardiovascular diseases, smoking, drinking, diabetes, hypertension and history of cerebral infarction. There was no significant difference in sex, education level, hyperlipidemia and hyperhomocysteinemia among the different age ranges. These findings confirm that age is an independent risk factor for the prevalence and severity of WMHs. The age-related risk factors enhance the occurrence of WMHs.

关键词： nerve regeneration white matter prevalence severity age risk factor retrospective analysis cerebrovascular neural regeneration

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Effects of traditional Chinese exercises and general aerobic exercises on older adults with sleep disorders: A systematic review and meta-analysis

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Journal of Integrative Medicine 2021年第6期19卷 493-502页

作者： Yang-hao-tian Wu wen-bo he Yin-yan Gao Xue-mei Han School of Public health Lanzhou UniversityLanzhou 730000Gansu ProvinceChina

Background:Sleep disorders are common in older adults and have a negative influence on their physical and mental *** aerobic exercises(GAEs)have long been used in the treatment of sleep disorders as a non-pharmacological ***,there is no consensus on the efficacy of traditional Chinese exercises(TCEs)for treating sleep disorders in older adults and the difference between TCEs and ***:This study assessed the effects of TCEs and GAEs on the sleep quality of older adults and the differences between these two *** strategy:Pub Med,Embase,Cochrane Library,Web of Science,China Biology Medicine disc,China National Knowledge Infrastructure,China Science Journal Database and Wanfang Data were searched from their inception to August *** criteria:Randomized controlled trials(RCTs)that evaluated the effects of TCEs and GAEs on older adults with sleep disorders were *** extraction and analysis:Data were extracted by two researchers working *** risk bias of included studies was assessed using the Cochrane Handbook for Systematic Reviews of Interventions 5.1.0 and the quality of evidence was assessed using the Grades of Recommendation,Assessment,Development and Evaluation *** Pittsburgh Sleep Quality Index(PSQI)was used to estimate sleep ***-analyses were performed to assess the total PSQI score of the exercise intervention as the primary outcome,and the scores of subjective sleep quality,sleep latency,sleep duration,habitual sleep efficiency,sleep disturbance,use of sleep medication and daytime dysfunction were assessed as secondary ***,sensitivity,and meta-regression analyses were conducted to assess the contribution of covariables to ***:A total of 22 RCTs(including 1747 participants)were included in the *** results indicated that TCEs(weighted mean difference[WMD]=-2.14,95%confidence interval[CI][-2.82,-1.46],Pheterogeneity:

关键词： Traditional Chinese exercise General aerobic exercise Older adults Sleep quality Tai Chi Meta-analysis

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Prolonged prothrombin time at admission predicts poor clinical outcome in COVID-19 patients

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World Journal of Clinical Cases 2020年第19期8卷 4370-4379页

作者： Lang Wang wen-bo he Xiao-Mei Yu Da-Long Hu Hong Jiang Department of Cardiology Renmin Hospital of Wuhan UniversityWuhan 430060Hubei ProvinceChina Cardiovascular Research Institute Wuhan UniversityWuhan 430060Hubei ProvinceChina Hubei Key Laboratory of Cardiology Wuhan 430060Hubei ProvinceChina School of Biotechnology and Biomolecular Sciences The University of New South WalesSydney 2052Australia

BACKGROUND Supported by the National Natural Science Foundation of China,*** prognostic value of coagulation disorder in coronavirus disease 2019(COVID-19)patients should be *** To investigate the abnormalities of coagulation parameters in the patients with COVID-19 and their prognostic *** Consecutive patients admitted in the isolation ward of Renmin Hospital of Wuhan University from January 31 to February 5,2020 with confirmed COVID-19 were *** primary outcomes were death and survival as of March ***,vital signs,comorbidities and laboratory tests were collected and compared between those who died and *** regression analysis for prognostic factors was ***-Meier analysis was used to compare the estimated survival rate between patients with prolonged prothrombin time and normal prothrombin *** The total number of patients with confirmed COVID-19 who were enrolled was *** median age was 62 years,and 95 patients(44.6%)were ***-one patients were critical(23.9%),79 patients were severe(37.1%)and 83 patients were moderate(39%).As of March 11,2020,99 patients were discharged(46.5%),79 patients(37.1%)stayed in the hospital and 35 patients(16.2%)*** time to death was 6(4-8)d,while median hospital stay was 32(22-36)d in survivors(Phe group of those who *** respiration rate at admission was higher in the group of those who died(Phe incidences of hypertension(P=0.028),cerebrovascular disease(Pher in the group of those who *** count was decreased in the group of those who died(P=0.002)whereas prothrombin time(Pboplastin time(P=0.033),concentration of D-dimer(Phe group of those who ***

关键词： COVID-19 Coagulation Prothrombin time Fibrin degradation products Prognosis Infectious disease

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Cesarean section and risk of childhood leukemia: a systematic review and meta-analysis

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World Journal of Pediatrics 2020年第5期16卷 471-479页

作者： Li-Li Jiang Yin-Yan Gao wen-bo he Ting Gan Hou-Qian Shan Xue-Mei Han School of Public health Lanzhou UniversityLanzhou 73000China

Background A large number of studies pointed that being delivered by cesarean section(CS)would affect the health outcomes of offspring,however,whether CS would affect the risk of childhood leukemia remained *** study conducted a meta-analysis to quantitatively evaluate whether being delivered by CS would influence the onset of childhood *** PubMed,Embase and Web of Science databases were searched from 3rd June,1950 to 13th October,2019 to identify the literature,which examined the relationship between CS and childhood *** study used Newcastle-Ottawa Scale to assess the quality of *** analyses were conducted on region,mode of delivery,design of the study and number of confounders ***'s test and Begg's test were performed to evaluate possible publication *** The pooled odds ratio(OR)estimates illustrated that children delivered by CS had a higher risk of developing leukemia[OR 1.10,95%confidence interval(CI)1.04-1.17,P=0.002]and lymphoblastic leukemia(OR 1.12,95%CI 1.03-1.23,P=0.009),while a significant association for myeloid leukemia was not observed(OR 1.05,95%CI 0.92-1.20,P=0.451).Results of subgroup analyses indicated that elective CS would increase the risk of childhood lymphoblastic leukemia(OR 1.16,95%CI 1.06-1.27,P=0.002).However,a statistical relationship between emergency CS and lymphoblastic leukemia was not observed(OR 1.07,95%CI 0.93-1.23,P=0.364).Conclusions CS would increase the risk of childhood lymphoblastic *** is worth noting that subgroup analyses shows that elective CS rather than emergency CS increases the risk of lymphoblastic leukemia in offspring.

关键词： Cesarean section Leukemia Lymphoblastic leukemia Meta-analysis

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End-to-end delay analysis for networked systems

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Frontiers of Information Technology & Electronic Engineering 2015年第9期16卷 732-743页

作者： Jie SheN wen-bo he Xue LIU Zhi-bo WANG Zhi WANG Jian-guo YAO Department of Control Science and Engineering Zhejiang University School of Computer Science Mc Gill University School of Computer Wuhan University Su zhou Institute of Wuhan University School of Software Shanghai Jiao Tong University

End-to-end delay measurement has been an essential element in the deployment of real-time services in networked systems. Traditional methods of delay measurement based on time domain analysis, however, are not efficient as the network scale and the complexity increase. We propose a novel theoretical framework to analyze the end-to-end delay distributions of networked systems from the frequency domain. We use a signal flow graph to model the delay distribution of a networked system and prove that the end-to-end delay distribution is indeed the inverse Laplace transform of the transfer function of the signal flow graph. ~vo efficient methods, Cramer＇s rule-based method and the Mason gain rule-based method, are adopted to obtain the transfer function. By analyzing the time responses of the transfer function, we obtain the end-to-end delay distribution. Based on our framework, we propose an efficient method using the dominant poles of the transfer function to work out the bottleneck links of the network. Moreover, we use the framework to study the network protocol performance. Theoretical analysis and extensive evaluations show the effectiveness of the proposed approach.

关键词： Networked system End-to-end Delay distribution

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Corrugated Graphene Paper Reinforced Silicone Resin Composite for Efficient Interface Thermal Management

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Chinese Journal of Polymer Science 2024年第7期42卷 1002-1014,I0010页

作者： bo-wen Wang heng Zhang Qing-Xia he Hui-Tao Yu Meng-Meng Qin Wei Feng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin300350China International Engineering Institute Tianjin UniversityTianjin300350China

With the rapid development of high-power-density electronic devices,interface thermal resistance has become a critical barrier for effective heat management in high-performance electronic ***,there is an urgent demand for advanced thermal interface materials(TIMs)with high cross-plane thermal conductivity and excellent compressibility to withstand increasingly complex operating *** achieve this aim,a promising strategy involves vertically arranging highly thermoconductive graphene on ***,with the currently available methods,achieving a balance between low interfacial thermal resistance,bidirectional high thermal conductivity,and large-scale production is ***,we prepared a graphene framework with continuous filler structures in in-plane and cross-plane directions by bonding corrugated graphene to planar graphene *** interface interaction between the graphene paper framework and polymer matrix was enhanced via surface functionalization to reduce the interface thermal *** resulting three-dimensional thermal framework endows the polymer composite material with a cross-plane thermal conductivity of 14.4 W·m^(-1)·K^(-1)and in-plane thermal conductivity of 130W·m^(-1)·K^(-1)when the thermal filler loading is 10.1 wt%,with a thermal conductivity enhancement per 1 wt%filler loading of 831%,outperforming various graphene structures as *** its high thermal conductivity,low contact thermal resistance,and low compressive modulus,the developed highly thermoconductive composite material demonstrates superior performance in TIM testing compared with TFLEX-700,an advanced commercial TIM,effectively solving the interfacial heat transfer issues in electronic *** novel filler structure framework also provides a solution for achieving a balance between efficient thermal management and ease of processing.

关键词： Graphene paper Vertically aligned structure Cross-plane thermal conductivity Low compressive modulus Thermal interface material

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Black hole evaporation and its remnants with the generalized uncertainty principle including a linear term

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Communications in Theoretical Physics 2024年第2期76卷 125-136页

作者： bo Yu Zheng-wen Long College of Physics Guizhou UniversityGuiyang550025China

In recent years,researchers have investigated the evaporation of Schwarzschild black holes using various forms of the generalized uncertainty principle(GUP),metric quantum correction,and noncommutative geometry,***,there are differences between the GUP correction and the other two methods in terms of describing the later stages of black hole ***,some studies argue that the GUP with a negative parameter cannot effectively correct black hole evaporation,while others contend that the positivity or negativity of the GUP parameters should not affect the correction *** the above into consideration,we reconsider black hole evaporation with the generalized uncertainty principle including a linear term(LGUP),and examine the case of negative *** results indicate that the evaporation behavior of both Schwarzschild black holes and Reissner–Nordstr?m black holes,under LGUP correction,is consistent with the results of metric quantum correction and non-commutative ***,the negative parameter LGUP can also effectively correct for black hole evaporation.

关键词： black hole evaporation generalized uncertainty principle negative parameter

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Characteristics of microscopic pore heterogeneity and development model of Wufeng‒Longmaxi Shales in the Pengshui area of south-east Chongqing

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Frontiers of Earth Science 2024年第1期18卷 188-203页

作者： Lu SUN Zhigang wen Guisong he Peixian ZHANG Chenjun WU Liwen ZHANG Yingyang XI bo LI College of Resources and Environment Yangtze UniversityWuhan 430100China Research Institute of Exploration and Development Sinopec East China CompanyNanjing 210011China

Normal-pressure shale gas reservoirs are widely distributed in south-eastern Chongqing and show good potential for resource *** paper reports the organic matter(OM),physical,and pore characteristics,mineral composition,and gas content of representative shale samples from the Upper Ordovician Wufeng Formation and Member 1 of the Lower Silurian Longmaxi Formation(Long 1 Member).Microscopic pores within different shale layers of the Long 1 Member were classified,quantitatively evaluated,and their development mechanisms were systematically *** found that OM characteristics,mineral composition,and pore type were the main factors affecting the enrichment and preservation of shale *** characteristics of the Long 1 Member are mainly controlled by changes in the sedimentary *** are evident differences in total organic carbon content and mineral composition vertically,leading to a variable distribution of pores across different *** matter abundance controls the degree of OM pore development,while clay minerals abundance control the development of clay mineral-related *** organic carbon content generally controls the porosity of the Long 1 Member,but clay minerals also play a role in OM-poor *** connectivity and permeability are influenced by the development of pores associated with brittle *** propose a microscopic pore development model for the different *** geochemical data and this pore development model,layers 1‒4 are considered to be excellent shale gas preservation and enrichment *** preservation conditions in layers 5‒7 result in high levels of shale gas *** 8‒9 possess a better sealing condition compared with layers 5‒7 and are conducive to the enrichment and preservation of shale gas,and can thus be used as future potential target *** research provides a theoretical basis for exploring and evaluating shale gas potential in the studied region or other co

关键词： shale gas pore characteristics Longmaxi Formation reservoir model

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Controlling and decision-making based on All Set Theory

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通讯和计算机（中英文版） 2007年第8期4卷 6-10页

作者： DING wen-bo he Zhong-xiong Beijing Jiaotong University Beijing 100044 China

As a newly discipline and methodology in the field of Artificial Intelligent, All Set Theory can be applied to describe macroscopic complex large systems and establish models in uncertain systems. The application of All Set Theory in controlling and decision-making for systems was discussed in the paper, furthermore, the Decision-making and Controlling System based on All Set Theory (AS-DCS) is put forward. At last, the model of AS-DCS and its structure as well as its program flow chart are presented.

关键词：统一集理论复杂系统决策控制人工智能

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