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含聚硅氧烷链段邻苯二甲腈树脂的制备及性能
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作者 蒋欣欣 赵星诺 +4 位作者 章宇琳 刘小僮 王文蓓 周权 张钧钧 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第2期1-8,共8页
以端羟基聚二甲基硅氧烷和4-硝基邻苯二甲腈为原料,在强极性溶剂中进行亲核取代反应合成了含聚硅氧烷链段邻苯二甲腈树脂(SIPH),并利用氨基改性剂(AWL)与该树脂进行反应制备了改性含聚硅氧烷链段邻苯二甲腈树脂预聚物(SIPH-AL)。通过红... 以端羟基聚二甲基硅氧烷和4-硝基邻苯二甲腈为原料,在强极性溶剂中进行亲核取代反应合成了含聚硅氧烷链段邻苯二甲腈树脂(SIPH),并利用氨基改性剂(AWL)与该树脂进行反应制备了改性含聚硅氧烷链段邻苯二甲腈树脂预聚物(SIPH-AL)。通过红外光谱和核磁共振表征了SIPH树脂的化学结构;采用差示扫描量热法、红外光谱法、热重分析和动态力学热分析表征了SIPH-AL的固化行为和固化物的耐热性。结果表明,SIPH-AL起始固化温度为207℃,其固化物在空气和氮气中失重5%的温度(T_(d5))及1000℃质量保留率分别是453℃,29%和500℃,77%;石英纤维增强SIPH-AL复合材料室温和600℃时的弯曲强度分别为515.5 MPa和94.5 MPa,玻璃化转变温度(T_(g))高于500℃。 展开更多
关键词 含聚硅氧烷链段邻苯二甲腈树脂 氨基改性剂 耐热性 复合材料
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3,3',4,4'-联苯四胺改性邻苯二甲腈树脂及其复合材料性能
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作者 董俊宇 赵星诺 +4 位作者 章宇琳 刘小僮 王文蓓 周权 吴霄 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第2期65-73,共9页
采用3,3',4,4'-联苯四胺(LBS)与联苯型邻苯二甲腈树脂(BPh)进行预聚反应制备改性联苯型邻苯二甲腈树脂预聚物(BLBS)。利用红外光谱法、差示扫描量热仪、旋转流变仪和热重分析对BLBS的固化行为、流变性能和耐温性能进行研究。结... 采用3,3',4,4'-联苯四胺(LBS)与联苯型邻苯二甲腈树脂(BPh)进行预聚反应制备改性联苯型邻苯二甲腈树脂预聚物(BLBS)。利用红外光谱法、差示扫描量热仪、旋转流变仪和热重分析对BLBS的固化行为、流变性能和耐温性能进行研究。结果表明,BLBS最低可在240℃前开始固化,但仍需要较高的温度才能固化完全;BLBS-3固化物在氮气和空气氛围中的质量损失5%时的温度(Td5)分别为549.4℃和555.6℃。石英纤维增强BLBS复合材料(QF/BLBS)具有优异的力学性能和耐热性能,玻璃化转变温度(T_(g))大于500°C,室温弯曲强度和层间剪切强度分别为711.5 MPa和48.5 MPa,400℃热处理2 h后弯曲强度和层间剪切强度分别为680.5 MPa和31.3 MPa。 展开更多
关键词 联苯型邻苯二甲腈 3 3' 4 4'-联苯四胺 耐热性能 力学性能 复合材料
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Wastewater Surveillance Provides Spatiotemporal SARS-CoV-2 Infection Dynamics
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作者 Xiawan Zheng Kathy Leung +14 位作者 Xiaoqing Xu Yu Deng yulin zhang Xi Chen Chung In Yau Kenny W.K.Hui Eddie Pak Ho-Kwong Chui Ron Yang Hein Min Tun Gabriel Matthew Leung Joseph Tsz Kei Wu Malik Peiris Leo Lit Man Poon Tong zhang 《Engineering》 SCIE EI CAS CSCD 2024年第9期70-77,共8页
Wastewater surveillance(WWS)can leverage its wide coverage,population-based sampling,and high monitoring frequency to capture citywide pandemic trends independent of clinical surveillance.Here we conducted a nine mont... Wastewater surveillance(WWS)can leverage its wide coverage,population-based sampling,and high monitoring frequency to capture citywide pandemic trends independent of clinical surveillance.Here we conducted a nine months daily WWS for severe acute respiratory syndrome coronavirus 2(SARSCoV-2)from 12 wastewater treatment plants(WWTPs),covering approximately 80%of the population,to monitor infection dynamics in Hong Kong,China.We found that the SARS-CoV-2 virus concentration in wastewater was correlated with the daily number of reported cases and reached two pandemic peaks three days earlier during the study period.In addition,two different methods were established to estimate the prevalence/incidence rates from wastewater measurements.The estimated results from wastewater were consistent with findings from two independent citywide clinical surveillance programmes(rapid antigen test(RAT)surveillance and serology surveillance),but higher than the cases number reported by the Centre for Health Protection(CHP)of Hong Kong,China.Moreover,the effective reproductive number(R_(t))was estimated from wastewater measurements to reflect both citywide and regional transmission dynamics.Our findings demonstrate that large-scale intensive WWS from WWTPs provides cost-effective and timely public health information,especially when the clinical surveillance is inadequate and costly.This approach also provides insights into pandemic dynamics at higher spatiotemporal resolutions,facilitating the formulation of effective control policies and targeted resource allocation. 展开更多
关键词 SARS-CoV-2 Wastewater surveillance PREVALENCE Effective reproductive number
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灾害的再生产与治理危机——中国经验的山西样本
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作者 张玉林 《中国乡村研究》 2013年第1期70-89,共20页
能源开发在很大程度上可以理解为“造灾”的过程。尽管这种典型的“人祸”具有可预见性,但是本文通过对山西省的相关状况的考察表明,由于复杂的政治、经济和社会体制的诸多缺陷交织到一起,使得造灾的动力巨大,从而将山西的大地肢解得“... 能源开发在很大程度上可以理解为“造灾”的过程。尽管这种典型的“人祸”具有可预见性,但是本文通过对山西省的相关状况的考察表明,由于复杂的政治、经济和社会体制的诸多缺陷交织到一起,使得造灾的动力巨大,从而将山西的大地肢解得“触目惊心、山河破碎”。同时由于有效的救灾机制难以形成,导致灾害不断地扩大再生产,受害区域和人数增加。而当对那些丧失了生存基础的农村居民的救助遥遥无期,“治理危机”实质上意味着生存危机,如何消除这种危机成为异常紧迫的问题。 展开更多
关键词 “矿山地质灾害” 灾害的再生产 中国经验 山西农村 治理危机
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A framework for equipment systems-of-systems effectiveness evaluation using parallel experiments approach 被引量:7
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作者 Zilong Cheng Li Fan yulin zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第2期292-300,共9页
Equipment systems-of-systems (SOS) effectiveness evaluation can provide important reference for construction and optimization of the equipment SoS. After discussing the basic theory and methods of parallel experimen... Equipment systems-of-systems (SOS) effectiveness evaluation can provide important reference for construction and optimization of the equipment SoS. After discussing the basic theory and methods of parallel experiments, we depict an SoS effectiveness analysis and evaluation method using parallel expe- riments theory in detail. A case study is carried out which takes the missile defense system as an example. An artificial system of the missile defense system is constructed with the multi-agent modeling method. Then, single factor, multiple factors and defense position deployment computational experiments are carried out and evaluated with the statistical analysis method. Experiment re- sults show that the altitude of the secondary interception missile is not the key factor which affects SoS effectiveness and putting the defense position ahead will increase defense effectiveness. The case study demonstrates the feasibility of the proposed method. 展开更多
关键词 agent based modeling parallel experiments computational experiments missile defense system effectiveness evaluation
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Targeting β-secretase with RNAi in neural stem cells for Alzheimer's disease therapy 被引量:4
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作者 Zhonghua Liu Shengliang Li +5 位作者 Zibin Liang Yan Zhao yulin zhang Yaqi Yang Minjuan Wang Feng Li 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第33期3095-3106,共12页
There are several major pathological changes in Alzheimer's disease, including apoptosis of cho- linergic neurons, overactivity or overexpression of 13-site amyloid precursor protein cleaving enzyme 1 (BACE1) and i... There are several major pathological changes in Alzheimer's disease, including apoptosis of cho- linergic neurons, overactivity or overexpression of 13-site amyloid precursor protein cleaving enzyme 1 (BACE1) and inflammation. In this study, we synthesized a 19-nt oligonucleotide targeting BACE1, the key enzyme in amyloid beta protein (AI3) production, and introduced it into the pSilenCircle vector to construct a short hairpin (shRNA) expression plasmid against the BACE1 gene. We transfected this vector into C17.2 neural stem cells and primary neural stem cells, resulting in downregulation of the BACE1 gene, which in turn induced a considerable reduction in reducing AI3 protein production. We anticipate that this technique combining cell transplantation and gene ther- apy will open up novel therapeutic avenues for Alzheimer's disease, particularly because it can be used to simultaneously target several pathogenetic changes in the disease. 展开更多
关键词 neural regeneration neurodegenerative disease SECRETASE neural stem cells Alzheimer'sdisease C17.2 neural stem cells primary neural stem cells shRNA PLASMID genetic modification grants-supported paper NEUROREGENERATION
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Multi-agent decision support system for missile defense based on improved PSO algorithm 被引量:5
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作者 Zilong Cheng Li Fan yulin zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期514-525,共12页
Ballistic missile defense system (BMDS) is important for its special role in ensuring national security and maintaining strategic balance. Research on modeling and simulation of the BMDS beforehand is essential as dev... Ballistic missile defense system (BMDS) is important for its special role in ensuring national security and maintaining strategic balance. Research on modeling and simulation of the BMDS beforehand is essential as developing a real one requires lots of manpower and resources. BMDS is a typical complex system for its nonlinear, adaptive and uncertainty characteristics. The agent-based modeling method is well suited for the complex system whose overall behaviors are determined by interactions among individual elements. A multi-agent decision support system (DSS), which includes missile agent, radar agent and command center agent, is established based on the studies of structure and function of BMDS. Considering the constraints brought by radar, intercept missile, offensive missile and commander, the objective function of DSS is established. In order to dynamically generate the optimal interception plan, the variable neighborhood negative selection particle swarm optimization (VNNSPSO) algorithm is proposed to support the decision making of DSS. The proposed algorithm is compared with the standard PSO, constriction factor PSO (CFPSO), inertia weight linear decrease PSO (LDPSO), variable neighborhood PSO (VNPSO) algorithm from the aspects of convergence rate, iteration number, average fitness value and standard deviation. The simulation results verify the efficiency of the proposed algorithm. The multi-agent DSS is developed through the Repast simulation platform and the constructed DSS can generate intercept plans automatically and support three-dimensional dynamic display of missile defense process. 展开更多
关键词 agent-based modeling missile defense system decision support system (DSS) variable neighborhood negative selection particle swarm optimization (PSO)
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Research Progress in Plant Invertase 被引量:2
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作者 yulin zhang Yuqiao CAO Nannan HU 《Agricultural Science & Technology》 CAS 2017年第1期21-22,34,共3页
Invertase is a key enzyme in sucrose catabolism and crucial for plant assimilate distribution. With the development of molecularbiology, a lot of invertsae genes were cloned recently, and significant progress have bee... Invertase is a key enzyme in sucrose catabolism and crucial for plant assimilate distribution. With the development of molecularbiology, a lot of invertsae genes were cloned recently, and significant progress have been made in regulators on the expression of invertase genes.Thus, this article summarized theresearch progress of invertase in biological characteristics, molecular characteristics and expression regulation. 展开更多
关键词 INVERTASE Sucrose catabolism Expression regulation
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Self-organizing strategy design and validation forintegrated air-ground detection swarm
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作者 Meiyan An Zhaokui Wang yulin zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第5期1018-1027,共10页
A self-organized integrated air-ground detection swarmis tentatively applied to achieve reentry vehicle landing detection,such as searching and rescuing a manned spaceship. The detectionswarm consists of multiple unma... A self-organized integrated air-ground detection swarmis tentatively applied to achieve reentry vehicle landing detection,such as searching and rescuing a manned spaceship. The detectionswarm consists of multiple unmanned aerial vehicles (UAVs)and unmanned ground vehicles (UGVs). The UAVs can accessa detected object quickly for high mobility, while the UGVs cancomprehensively investigate the object due to the variety of carriedequipment. In addition, the integrated air-ground detectionswarm is capable of detecting from the ground and the air simultaneously.To accomplish the coordination of the UGVs andUAVs, they are all regarded as individuals of the artificial swarm.Those individuals make control decisions independently of othersbased on the self-organizing strategy. The overall requirements forthe detection swarm are analyzed, and the theoretical model ofthe self-organizing strategy based on a combined individual andenvironmental virtual function is established. The numerical investigationproves that the self-organizing strategy is suitable andscalable to control the detection swarm. To further inspect the engineeringreliability, an experiment set is established in laboratory,and the experimental demonstration shows that the self-organizingstrategy drives the detection swarm forming a close range and multiangularsurveillance configuration of a landing spot. 展开更多
关键词 artificial swarm virtual potential field self-organizing integrated air-ground detection swarm.
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Effects of Transplanting Date on Growth, Development, Yield and Quality of Flue-cured Tobacco in Western Henan
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作者 Junzheng LI Haiyang JIANG +4 位作者 Jun HU Chunmiao QI Xiangguo CHENG Weiwei WANG yulin zhang 《Agricultural Biotechnology》 CAS 2019年第2期90-93,100,共5页
With Yunyan 87 as an experimental material, the effects of different transplanting dates on the growth and development of tobacco plants and the yield and quality of cured tobacco leaves were studied in Lingbao City, ... With Yunyan 87 as an experimental material, the effects of different transplanting dates on the growth and development of tobacco plants and the yield and quality of cured tobacco leaves were studied in Lingbao City, Sanmenxia City. With the postponement of transplanting date, the growth period in field was prolonged, and the plant height and leaf area both increased at first and decreased then. TMV, weather fleck and brown spot all showed an incidence and a disease index decreased with the postponement of transplanting date. The total sugar and reducing sugar contents of the cured tobacco leaves from the upper and middle part increased at first and decreased then with the postponement of transplanting date. The main nitrogenous compounds decreased at first and increased then. The economic traits and leaf class were on the decrease. 展开更多
关键词 TRANSPLANTING DATE GROWTH and DEVELOPMENT Chemical components Quality
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Rockburst prediction and prevention in underground space excavation 被引量:1
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作者 Jian Zhou yulin zhang +2 位作者 Chuanqi Li Haini He Xibing Li 《Underground Space》 SCIE EI CSCD 2024年第1期70-98,共29页
The technical challenges associated with deep underground space activities have become increasingly significant.Among these challenges,one major concern is the assessment of rockburst risks and the instability of rock... The technical challenges associated with deep underground space activities have become increasingly significant.Among these challenges,one major concern is the assessment of rockburst risks and the instability of rock masses.Extensive research has been conducted by numerous scholars to mitigate the risks and prevent occurrences of rockburst through various assessment methods.Rockburst incidents commonly occur during the excavation of hard rock in underground environments,posing severe threats to personnel safety,equipment integrity,and operational continuity.Thus,it is crucial to systematically document real cases of rockburst,allowing for a comprehensive understanding of the underlying mechanisms and triggering conditions.This understanding will contribute to the advancement of rockburst prediction and prevention methods.Proper selection of an appropriate rockburst assessment method is a fundamental aspect in underground operations.However,there is a limited number of studies that summarize and compare different prediction and prevention methods of rockburst.This paper aims to address this gap by analyzing global trends using CiteSpace software since 1990.It discusses rockburst classification and characteristics,comprehensively reviews research findings related to rockburst prediction,including empirical,simulation,mathematical modeling,and microseismic monitoring methods.Additionally,the paper presents a compilation of current rockburst prevention measures.Notably,the paper emphasizes the significance of control strategies,which provide key insights into the effective utilization of stored energy within rock.Finally,the paper concludes by suggesting six directions for implementing intelligent management techniques to mitigate hazards during underground operations and reduce the probability of rockburst incidents. 展开更多
关键词 ROCKBURST Underground space Scientometric analysis Characteristic analysis Rockburst prediction Rockburst prevention
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基于Sentinel-1A SAR的洞庭湖汛期水体面积动态变化监测研究
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作者 张雨林 蒋昌波 +1 位作者 隆院男 闫世雄 《遥感技术与应用》 CSCD 北大核心 2024年第3期741-752,共12页
洞庭湖水体面积动态变化监测对防洪、维系生态系统的稳定及生物多样性具有重要意义。以经典Unet网络模型和创新性HRNet网络模型为代表的深度学习技术已成为遥感图像信息获取的高效途径,实验以Sentinel-1A SAR影像为主要数据源,定性、定... 洞庭湖水体面积动态变化监测对防洪、维系生态系统的稳定及生物多样性具有重要意义。以经典Unet网络模型和创新性HRNet网络模型为代表的深度学习技术已成为遥感图像信息获取的高效途径,实验以Sentinel-1A SAR影像为主要数据源,定性、定量地分析了Sentinel-1双极化水体指数法(Sentinel-1 Dual-Polarized Water Index,SDWI)、面向对象分类法、UNet网络模型和HRNet网络模型4种方法的水体提取效果,并基于最佳水体提取方法对洞庭湖2016~2021年汛期(4~10月)水体面积进行时空变化特征分析。结果表明:①HRNet和Unet网络模型较传统方法具有更优的水体提取效果,其中,HRNet网络模型在抑噪、抗阴影等方面表现更佳,F1分数、误判率和平均交并比分别为0.9616、0.0078和0.9586;②汛期洞庭湖水体面积在月际变化上呈现出“涨—丰—退”的变化特征,湖面从4~5月份开始扩张,6~8月份水域面积维持在较高水平,此后由于来水减少,9~10月的水体面积逐步减小。研究期间所监测到的最大水体面积为2020年7月30日的2263.90 km2;③洞庭湖汛期的水体淹没频率从湖体中心和干流向外逐渐降低,不同湖区的淹没频率分布格局不同,东洞庭湖“湖心高四周低”,南洞庭湖和西洞庭湖“南高北低”。综上所述,Sentinel-1A SAR影像与深度学习技术的结合应用可以实现洞庭湖水体信息高效获取与水面面积高频监测,为高动态湖泊水域监测提供了一种新思路。 展开更多
关键词 洞庭湖 水体面积 Sentinel-1A 深度学习 HRNet
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Optimal Timing of Antiretroviral Therapy Initiation in Acquired Immunodeficiency Syndrome-Associated Toxoplasmic Encephalitis:A Prospective Observational Multicenter Study in China 被引量:1
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作者 Yao Li Haidong Jiang +7 位作者 Yanming Zeng Yanqiu Lu Siyuan Chen yulin zhang Zhongsheng Jiang Tongtong Yang Shuiqing Liu Yaokai Chen 《Infectious Diseases & Immunity》 CSCD 2024年第1期4-9,共6页
Background:Toxoplasmic encephalitis(TE)is the most frequent cause of expansive brain lesions among patients with acquired immunodeficiency syndrome(AIDS).However,the optimal timing of antiretroviral therapy(ART)initia... Background:Toxoplasmic encephalitis(TE)is the most frequent cause of expansive brain lesions among patients with acquired immunodeficiency syndrome(AIDS).However,the optimal timing of antiretroviral therapy(ART)initiation in these patients remains controversial.This study aims to investigate the differences in outcomes of ART initiation at different times,in order to help clarify the treatment timing of AIDS-associated TE.Methods:This multicenter prospective observational study included 87 patients recruited from 11 research centers in China(from March 2019 to December 2022).Of the patients,38 were assigned to the early ART group(initiating ART within 2 weeks after anti-Toxoplasma treatment initiation),and the remaining 49 patients received deferred ART(initiating ART at least 2 weeks after anti-Toxoplasma treatment initiation).The main outcomes includedmortality and emergence of immune reconstitution inflammatory syndrome(IRIS).Human immunodeficiency virus(HIV)-1 viral load and CD4^(+)T-cell counts at weeks 24 and 48 were observed.Results:The number of deaths(1 vs.5,P=0.225)and incidence of IRIS(2.6%vs.0,P=0.437)were not significantly different between the early and deferred ART groups at week 48.Early ART initiation did not contribute significantly to HIV-1 viral load control(<50 copies/mL,n=8 vs.n=3 at week 24,P=0.142;n=7 vs.n=7 atweek 48,P=1.000).The median CD4^(+)T-cell counts between the two groups were not significantly different,either at week 24(155 vs.91 cells/mm^(3),P=0.837)or atweek 48(181 vs.146 cells/mm^(3),P=0.219).Conclusion:In patients with AIDS-associated TE,early ART initiation was not significantly different from deferred ART initiation in terms of incidence of mortality,IRIS,and HIV virological and immunological outcomes.Trial registration:This study was registered(registration number:ChiCTR1900021195)as one of 12 clinical trials under the title of a general project at the Chinese Clinical Trial Registry(chictr.gov)on February 1,2019.Enrollment for this study began inMarch 2019. 展开更多
关键词 HIV Toxoplasma gondii Timing of antiretroviral therapy Virological outcome Immunological response
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The super-pangenome of Populus unveils genomic facets for its adaptation and diversification in widespread forest trees
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作者 Tingting Shi Xinxin zhang +18 位作者 Yukang Hou Changfu Jia Xuming Dan yulin zhang Yuanzhong Jiang Qiang Lai Jiajun Feng Jianju Feng Tao Ma Jiali Wu Shuyu Liu Lei zhang Zhiqin Long Liyang Chen Nathaniel R.Street Par K.Ingvarsson Jianquan Liu Tongming Yin Jing Wang 《Molecular Plant》 SCIE CSCD 2024年第5期725-746,共22页
Understanding the underlying mechanisms and links between genome evolution and adaptive innovations stands as a key goal in evolutionary studies.Poplars,among the world’s most widely distributed and cultivated trees,... Understanding the underlying mechanisms and links between genome evolution and adaptive innovations stands as a key goal in evolutionary studies.Poplars,among the world’s most widely distributed and cultivated trees,exhibit extensive phenotypic diversity and environmental adaptability.In this study,we present a genus-level super-pangenome comprising 19 Populus genomes,revealing the likely pivotal role of private genes in facilitating local environmental and climate adaptation.Through the integration of pangenomes with transcriptomes,methylomes,and chromatin accessibility mapping,we unveil that the evolutionary trajectories of pangenes and duplicated genes are closely linked to local genomic landscapes of regulatory and epigenetic architectures,notably CG methylation in gene-body regions.Further comparative genomic analyses have enabled the identification of 142202 structural variants across species that intersect with a significant number of genes and contribute substantially to both phenotypic and adaptive divergence.We have experimentally validated a∼180-bp presence/absence variant affecting the expression of the CUC2 gene,crucial for leaf serration formation.Finally,we developed a user-friendly web-based tool encompassing the multi-omics resources associated with the Populus super-pangenome(http://www.populus-superpangenome.com).Together,the present pioneering super-pangenome resource in forest trees not only aids in the advancement of breeding efforts of this globally important tree genus but also offers valuable insights into potential avenues for comprehending tree biology. 展开更多
关键词 POPULUS pangenomes whole-genome duplication structural variation genome evolution
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A high-performance electrocatalyst for oxygen reduction derived from copolymer-anchored polyoxometalates
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作者 Yue Du Wenxue Chen +8 位作者 Zhiyi Zhong Zhixian Shi yulin zhang Xuanning Chen Yisi Liu Dongbin Xiong Lina Zhou Zhenhui Liu Mingbo Zheng 《Nano Research》 SCIE EI CSCD 2024年第6期5197-5205,共9页
The development and synthesis of cathode electrocatalysts with high activity and durable stability for metal-air batteries is an important challenge in the area of electrocatalysis.Herein,we introduce a novel in-situ ... The development and synthesis of cathode electrocatalysts with high activity and durable stability for metal-air batteries is an important challenge in the area of electrocatalysis.Herein,we introduce a novel in-situ nitriding and phosphating strategy for producing W_(3)N_(4)and WP from phosphotungstic acid(HPW)-polyaniline-phytic acid-Fe3+organic-inorganic hybrid material.The final material has a three-dimensional porous framework with W_(3)N_(4)-WP heterostructures embedded in the carbon matrix(W_(3)N_(4)-WP@NPC).As-made materials exhibit exceptional electrocatalytic performance for the oxygen reduction reaction(ORR),with a diffusion-limiting current density of 6.9 mA·cm^(−2)and a half-wave potential of 0.82 V.As a Zn-air primary cathode,the W_(3)N_(4)-WP@NPC assembled battery can provide a relatively high peak power density(194.2 mW·cm^(−2)).As a Zn-air secondary air-cathode,it has great cycling stability over 500 h.This work provides a simple and efficient method for rationally designing high-performance air cathodes from copolymer-anchored polyoxometalates. 展开更多
关键词 W_(3)N_(4)-WP heterojunctions copolymer-anchored polyoxometalates oxygen reduction reaction Zn-air battery
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Simultaneous multiplex genome loci editing of Halomonas bluephagenesis using an engineered CRISPR-guided base editor
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作者 yulin zhang Yang Zheng +5 位作者 Qiwen Hu Zhen Hu Jiyuan Sun Ping Cheng Xiancai Rao Xiao-Ran Jiang 《Synthetic and Systems Biotechnology》 SCIE CSCD 2024年第3期586-593,共8页
Halomonas bluephagenesis TD serves as an exceptional chassis for next generation industrial biotechnology to produce various products.However,the simultaneous editing of multiple loci in H.bluephagenesis TD remains a ... Halomonas bluephagenesis TD serves as an exceptional chassis for next generation industrial biotechnology to produce various products.However,the simultaneous editing of multiple loci in H.bluephagenesis TD remains a significant challenge.Herein,we report the development of a multiple loci genome editing system,named CRISPR-deaminase-assisted base editor(CRISPR-BE)in H.bluephagenesis TD.This system comprises two components:a cytidine(CRISPR-cBE)and an adenosine(CRISPR-aBE)deaminase-based base editor.CRISPR-cBE can introduce a cytidine to thymidine mutation with an efficiency of up to 100%within a 7-nt editing window in H.bluephagenesis TD.Similarly,CRISPR-aBE demonstrates an efficiency of up to 100%in converting adenosine to guanosine mutation within a 7-nt editing window.CRISPR-cBE has been further validated and successfully employed for simultaneous multiplexed editing in H.bluephagenesis TD.Our findings reveal that CRISPR-cBE efficiently inactivated all six copies of the IS1086 gene simultaneously by introducing stop codon.This system achieved an editing efficiency of 100%and 41.67%in inactivating two genes and three genes,respectively.By substituting the Pcas promoter with the inducible promoter PMmp1,we optimized CRISPR-cBE system and ultimately achieved 100%editing efficiency in inactivating three genes.In conclusion,our research offers a robust and efficient method for concurrently modifying multiple loci in H.bluephagenesis TD,opening up vast possibilities for industrial applications in the future. 展开更多
关键词 Base editor Gene editing Multiplex Halomonas bluephagenesis
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Comparison of Ex‑PRESS implantation versus trabeculectomy combined with phacoemulsification in primary open‑angle glaucoma:a retrospective in vivo confocal microscopy study
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作者 Yuqiao zhang Beiting He +6 位作者 yulin zhang Jin Zeng Yanlei Chen Yongyi Niu Honghua Yu Yongjie Qin Hongyang zhang 《Eye and Vision》 SCIE CSCD 2024年第2期1-11,共11页
Background:To compare the efficacy of Ex-PRESS implantation versus trabeculectomy combined with phacoemulsification.Methods:A retrospective 12-month study on patients with coincident primary open-angle glaucoma(POAG)a... Background:To compare the efficacy of Ex-PRESS implantation versus trabeculectomy combined with phacoemulsification.Methods:A retrospective 12-month study on patients with coincident primary open-angle glaucoma(POAG)and cataract.The patients underwent combined phacoemulsification and Ex-PRESS implant(Phaco-ExPRESS,n=35)or phacotrabeculectomy(Phaco-Trab,n=35).The morphological structures of the filtering bleb were examined by slitlamp,anterior segment optical coherence tomography(AS-OCT)and in vivo confocal microscopy(IVCM).Complete success was defined as postoperative intraocular pressure(IOP)<18 mmHg without the use of anti-glaucoma medication.Qualified success was defined as postoperative IOP<18 mmHg with or without anti-glaucoma medications.The data were collected preoperatively and postoperatively at 2 weeks,1 month,3 months,6 months,and 12 months.Results:No significant difference in the variables such as age,IOP and perimetry was found between the groups of Phaco-ExPRESS and Phaco-Trab.At the one-year postoperative visit for filtering blebs,Phaco-ExPRESS increased the mean area of epithelial microcysts significantly from 0.10±0.05 to 0.20±0.09μm^(2)perμm^(2),while Phaco-Trab decreased the mean area significantly from 0.08±0.04 to 0.04±0.06μm^(2)perμm^(2).Notably,the hyperreflective dots detected by IVCM decreased by 84.9%in Phaco-ExPRESS but increased by 36.3%in Phaco-Trab.The hyperreflective dots were further identified as neutrophil-and monocyte-like cells.The number of these cells were negatively correlated with the microcysts area(r=−0.7,P<0.01)but positively associated with the grade of connective tissue(r=0.5,P<0.01).By creating different microstructural changes in the filtering blebs,Phaco-ExPRESS produced a higher complete success rate(84.9%vs.41.2%,P<0.01)and significant decrease in the number of anti-glaucoma medications(P<0.01)when compared with those in Phaco-Trab.However,the qualified success showed no significant difference between the two groups(100.0%vs.91.2%,P=0.24).Conclusions:At the one-year follow-up,Phaco-ExPRESS generated better filtering bleb with larger area of microcysts,looser connective tissues,and less inflammation than that of Phaco-Trab,providing adequate IOP control and less IOP-lowering medications.These findings indicate that Phaco-ExPRESS could be more preferred than Phaco-Trab for the treatment of patients with coincident POAG and cataract. 展开更多
关键词 POAG Ex-PRESS PHACOEMULSIFICATION Confocal microscopy
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The differential effects of integrase strand transfer inhibitors and efavirenz on neuropsychiatric conditions and brain imaging in HIV-positive men who have sex with men
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作者 Yihui He Yang zhang +12 位作者 Jiaxin Zhen Guangqiang Sun Zhen Li Bo Yang Bin Yang Keyi Chang Xue Chen yulin zhang Caiping Guo Wen Wang Ping Wu Tong zhang Lei Wang 《Biosafety and Health》 CAS CSCD 2024年第4期216-224,共9页
Integrase strand transfer inhibitors(INSTIs)have emerged as the first‐line choice for treating human immunodeficiency virus(HIV)infection due to their superior efficacy and safety.However,the impact of INSTIs on the ... Integrase strand transfer inhibitors(INSTIs)have emerged as the first‐line choice for treating human immunodeficiency virus(HIV)infection due to their superior efficacy and safety.However,the impact of INSTIs on the development of neuropsychiatric conditions in people living with HIV(PLWH)is not fully understood due to limited data.In this study,we conducted a cross‐sectional examination of PLWH receiving antiretroviral therapy,with a specific focus on HIV‐positive men who have sex with men(MSM)on INSTI‐based regimens(n=61)and efavirenz(EFV)‐based regimens(n=28).Participants underwent comprehensive neuropsychiatric evaluations and multimodal magnetic resonance imaging(MRI)scans,including T1‐weighted images and resting‐state functional MRI.Compared to the EFV group,the INSTI group exhibited primarily reduced gray matter volume(GMV)in the right superior parietal gyrus,higher regional homogeneity(ReHo)in the left postcentral gyrus,lower ReHo in the right orbital part of the inferior frontal gyrus,and increased voxel‐wise functional connectivity for the seed region in the left inferior temporal gyrus with clusters in the right cuneus.Furthermore,the analysis revealed a main effect of antiretroviral drugs on GMV changes,but no main effect of neuropsychiatric disorders or their interaction.The repeated analysis of participants who did not switch regimens confirmed the GMV changes in the INSTI group,validating the initial findings.Our study demonstrated gray matter atrophy and functional brain changes in PLWH on INSTI‐based regimens compared to those on EFV‐based regimens.These neuroimaging results provide valuable insights into the characteristics of brain network modifications in PLWH receiving INSTI‐based regimens。 展开更多
关键词 Human immunodeficiency virus(HIV) Multimodal magnetic resonance imaging(MRI) Integrase strand transfer inhibitors(INSTIs) Efavirenz(EFV)
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具有超高灵敏度、宽工作范围、低检测限的3D气凝胶可穿戴压力传感器用于语音识别和生理信号监测 被引量:1
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作者 尚成硕 何翔天 +9 位作者 李晓迪 刘泽瑞 宋玉祥 张玉林 李旭 鲁勇 丁小康 刘婷 张纪才 徐福建 《Science China Materials》 SCIE EI CAS CSCD 2023年第5期1911-1922,共12页
随着智能电子设备的快速发展,对同时具有超高灵敏度、宽工作范围、低检测限的可穿戴压力传感器的需求越来越大.本文开发了一种基于超轻(29.5 mg cm^(-3))和弹性的3D壳聚糖/MXene(CS/MXene)复合气凝胶的压阻式压力传感器.由于CS和MXene... 随着智能电子设备的快速发展,对同时具有超高灵敏度、宽工作范围、低检测限的可穿戴压力传感器的需求越来越大.本文开发了一种基于超轻(29.5 mg cm^(-3))和弹性的3D壳聚糖/MXene(CS/MXene)复合气凝胶的压阻式压力传感器.由于CS和MXene之间的强静电吸引力,具有良好机械性能的CS/MXene气凝胶只需一步冷冻干燥即可获得,无需额外的化学处理.CS/MXene复合气凝胶压力传感器在小压力区(<1 kPa)和大压力区(1-20 kPa)的灵敏度分别为709.38和252.37 kPa^(-1).在此压力范围下,其灵敏度是目前报道的同类型气凝胶压力传感器的最高值.此外,该传感器具有快速的响应时间(<120 ms)、1.4 Pa的超低检测限以及10,000次循环后几乎无衰减的良好稳定性.以上出色的性能不仅使得该传感器可用于检测肢体活动和空间压力分布等较大幅度的压力信号,而且还能准确检测脉搏、语音等微小压力信号.这种多功能的柔性压力传感器极大地拓宽了可穿戴电子器件在语音识别、健康监测和人机交互等诸多领域的应用范围. 展开更多
关键词 wearable electronics CS/MXene aerogel piezoresistive pressure sensor voice recognition health monitoring
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利用改良培养基探究西太平洋海水可培养细菌多样性 被引量:12
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作者 孙创 王金燕 +4 位作者 张钰琳 张蕴慧 朱晓雨 陈朝晖 张晓华 《微生物学报》 CAS CSCD 北大核心 2021年第4期845-861,共17页
【目的】西太平洋复杂的海洋生态环境孕育了其独特的生物群落,蕴含着种类丰富的海洋微生物资源。本研究基于分离培养技术探究了西太平洋海域不同水深细菌的多样性,并尝试通过改良培养基提高海洋细菌可培养性。【方法】采用改良的2216E... 【目的】西太平洋复杂的海洋生态环境孕育了其独特的生物群落,蕴含着种类丰富的海洋微生物资源。本研究基于分离培养技术探究了西太平洋海域不同水深细菌的多样性,并尝试通过改良培养基提高海洋细菌可培养性。【方法】采用改良的2216E固体培养基(IMA)、R2A固体培养基(R2A)、MBM固体培养基(MBM)、TCBS固体培养基(TCBS)和改良的2216E液体富集培养基(IMB)5种不同培养基进行微生物培养,通过菌株分离纯化、16S rRNA基因序列鉴定,分析西太平洋表层至6000 m水深可培养细菌的多样性以及不同培养基在分离培养异养细菌方面的优势。【结果】本研究共获得1293株异养细菌,分属于4门7纲14目26科52属119种,其中变形菌门(Proteobacteria)为主导类群。纲水平上,γ-变形菌纲(Gammaproteobacteria)、α-变形菌纲(Alphaproteobacteria)和放线菌纲(Actinobacteria_c)为优势菌群。5种培养基所获得的最优势门都为变形菌门,最优势纲都为γ-变形菌纲,除TCBS培养基优势目是弧菌目(Vibrionales),最优势目都为交替单胞菌目(Alteromonadales)。此外,5种培养基在各分类水平上均体现出不同的选择性。5种培养基在种水平上可培养细菌多样性由高到低依次为R2A、IMA、MBM、TCBS以及IMB。分离自R2A的特有属数目最多,可达10个。随水深增加,可培养异养微生物属的数量呈减少趋势。分得菌株中共有68株为潜在新菌,新菌率在IMA、R2A和MBM中相对较高。【结论】本研究用5种不同培养基从西太平洋海水中获得大量可培养细菌,具有较高的多样性,同时揭示了不同培养基对可培养海洋细菌的选择性。本研究为进一步的生态学研究和分子生物学研究等提供了宝贵的种质资源,也为未来利用改良培养基分离难培养海洋微生物带来启发。 展开更多
关键词 西太平洋 细菌多样性 16S RRNA 基因 改良培养基
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