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超分辨成像及超分辨关联显微技术研究进展

物理学报 2017年第14期66卷 246-268页

作者：林丹樱屈军乐深圳大学光电工程学院光电子器件与系统教育部/广东省重点实验室深圳518060

光学成像系统中有限孔径对光波的衍射,使得光学显微成像技术的分辨率受到"衍射极限"限制而无法进一步提高.自1873年E.K.Abbe提出该问题以来,衍射极限就一直是学术界研究的热点.近年来,随着高强度激光、高灵敏探测器等光电器件研制技术... 详细信息

光学成像系统中有限孔径对光波的衍射,使得光学显微成像技术的分辨率受到"衍射极限"限制而无法进一步提高.自1873年E.K.Abbe提出该问题以来,衍射极限就一直是学术界研究的热点.近年来,随着高强度激光、高灵敏探测器等光电器件研制技术以及新型荧光探针开发等相关领域的快速发展,光学显微技术衍射极限问题的研究迎来了新的契机,超分辨显微成像技术(super-resolution microscopy.SRM)在近十年内取得了令人瞩目的巨大成就.本文从空域和频域角度回顾了衍射极限分辨率的基本原理,并据此对目前常见的各种SRM技术"绕过"衍射极限提高分辨率的机理给予了详解,同时介绍了各类技术的发展动态和研究方向;作为SRM的一个新的重要的发展趋势,本文详细介绍了超分辨关联显微技术的最新研究进展,包括SRM与活细胞实时荧光显微、荧光寿命显微、光谱测量和成像、电子显微、原子力显微、质谱技术等的关联,着重讨论了各类超分辨关联显微技术的作用和意义;最后,对SRM技术和超分辨关联显微技术的未来发展方向进行了展望.

关键词：衍射极限超分辨成像关联显微技术超分辨关联显微技术

Mitochondrial Oxidative Stress Enhances Vasoconstriction by Altering Calcium Homeostasis in Cerebrovascular Smooth Muscle Cells under Simulated Microgravity

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Biomedical and Environmental Sciences 2021年第3期34卷 203-212页

作者： LIU Zi Fan WANG Hai Ming JIANG Min WANG lin lin le Jian ZHAO Yun Zhang SHAO Jun Jie ZHOU Jing Jing XIE Man Jiang LI Xin ZHANG Ran Department of Cardiovascular Medicine Chinese PLA General Hospital&Chinese PLA Medical SchoolBeijing 100853China Department of Cardiology The Eighth Medical Center of Chinese PLA General HospitalBeijing 100193China The First Clinical Medical College of Inner Mongolia Medical University Hohhot 010059Inner MongoliaChina Department of Aerospace Physiology Key Laboratory of Aerospace Medicine of Ministry of EducationFourth Military Medical UniversityXi'an 710032ShaanxiChina Division of Health services The First Medical Center of Chinese PLA General HospitalBeijing 100853China

Objective Exposure to microgravity results in postflight cardiovascular deconditioning in astronauts.Vascular oxidative stress injury and mitochondrial dysfunction have been reported during this process.To elucidate the mechanism for this condition,we investigated whether mitochondrial oxidative stress regulates calcium homeostasis and vasoconstriction in hindlimb unweighted(HU)rat cerebral arteries.Methods Three-week HU was used to simulate microgravity in rats.The contractile responses to vasoconstrictors,mitochondrial fission/fusion,Ca^(2+) distribution,inositol 1,4,5-trisphosphate receptor(IP3 R)abundance,and the activities of voltage-gated K+channels(KV)and Ca^(2+)-activated K+channels(BKCa)were examined in rat cerebral vascular smooth muscle cells(VSMCs).Results An increase of cytoplasmic Ca^(2+) and a decrease of mitochondrial/sarcoplasmic reticulum(SR)Ca^(2+) were observed in HU rat cerebral VSMCs.The abundance of fusion proteins(mitofusin 1/2[MFN1/2])and fission proteins(dynamin-related protein 1[DRP1]and fission-mitochondrial 1[FIS1])was significantly downregulated and upregulated,respectively in HU rat cerebral VSMCs.The cerebrovascular contractile responses to vasoconstrictors were enhanced in HU rats compared to control rats,and IP3 R protein/mRNA levels were significantly upregulated.The current densities and open probabilities of KV and BKCa decreased and increased,respectively.Treatment with the mitochondrial-targeted antioxidant mitoTEMPO attenuated mitochondrial fission by upregulating MFN1/2 and downregulating DRP1/FIS1.It also decreased IP3 R expression levels and restored the activities of the KV and BKCa channels.MitoTEMPO restored the Ca^(2+) distribution in VSMCs and attenuated the enhanced vasoconstriction in HU rat cerebral arteries.Conclusion The present results suggest that mitochondrial oxidative stress enhances cerebral vasoconstriction by regulating calcium homeostasis during simulated microgravity.

关键词： Microgravity Mitochondrial oxidative stress Calcium homeostasis Vasoconstriction

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腹腔镜右半结肠癌手术腔内吻合操作要点

中国实用外科杂志 2023年第10期43卷 1136-1139页

作者：林国乐李干斌中国医学科学院、北京协和医学院北京协和医院基本外科北京100730

消化道重建是右半结肠癌手术的关键之处。在完全腹腔镜背景下,腔内吻合更加符合微创化、疼痛和不适感更轻、术后恢复更快的加速康复外科理念,可能会成为腹腔镜右半结肠癌手术的首选吻合方式。在吻合过程中,需注意“点-线-面”的有机统一... 详细信息

消化道重建是右半结肠癌手术的关键之处。在完全腹腔镜背景下,腔内吻合更加符合微创化、疼痛和不适感更轻、术后恢复更快的加速康复外科理念,可能会成为腹腔镜右半结肠癌手术的首选吻合方式。在吻合过程中,需注意“点-线-面”的有机统一,即以戳口处为点,吻合钉为线,横结肠及回肠并行排列构成面,点在线上,线在面上,完成高质量的吻合。

关键词：右半结肠癌腹腔镜腔内吻合

Online Survey on Accessing Psychological Knowledge and Interventions During the COVID-19 Pandemic-China, 2020

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China CDC weekly 2020年第41期2卷 797-803页

作者： Qingdong Lu lin Liu Yunhe Wang le Shi Yingying Xu Zhengan Lu Jianyu Que Jingli Yue Kai Yuan Wei Yan Yankun Sun Jie Shi Yanping Bao lin Lu National Institute on Drug Dependence and Beijing Key Laboratory of Drug Dependence Peking UniversityBeijingChina School of Public Health Peking UniversityBeijingChina Institute of Mental Health National Clinical Research Center for Mental DisordersKey Laboratory of Mental Health and Peking University Sixth HospitalPeking UniversityBeijingChina Peking-Tsinghua Center for Life Sciences and PKU-IDG/McGovern Institute for Brain Research Peking UniversityBeijingChina

Summary What is already known on this topic?The public was at elevated risk of mental health illnesses during the coronavirus disease 2019(COVID-19)pandemic,so accessibility to psychological knowledge and interventions is vital to promptly respond to mental health crises.What is added by this report?During the pandemic period,40,724(71.9%)participants reportedly had access to psychological knowledge,and 36,546(64.5%)participants had accessed information on psychological interventions.Participants who were male,unmarried,living alone,divorced or widowed,or infected with COVID-19 were less likely to access psychological knowledge and intervention.

关键词： COV prompt Access

隧道无支撑长度对开挖面稳定性影响的离心模型试验

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岩土工程学报 2022年第S02期44卷 101-106页

作者：牛豪爽翁效林胡继波侯乐乐长安大学特殊地区公路工程教育部重点实验室陕西西安710061

考虑了隧道开挖过程中无支撑长度的影响,结合机械手系统开发了一整套离心试验装置。通过开展不同无支撑长度下C/D、内摩擦角的离心试验,研究了在考虑无支撑长度下不同土质开挖面支护力变化规律及失稳模式机理,提出了应考虑无支撑长度上... 详细信息

考虑了隧道开挖过程中无支撑长度的影响,结合机械手系统开发了一整套离心试验装置。通过开展不同无支撑长度下C/D、内摩擦角的离心试验,研究了在考虑无支撑长度下不同土质开挖面支护力变化规律及失稳模式机理,提出了应考虑无支撑长度上方土体的双块失稳体。结果显示,在考虑无支撑的条件下,土体的失稳由无支撑上方土体和开挖面前方土体两部分组成,且两部分不是同时发生失稳,打破了传统对于开挖面失稳的认知;随着C/D的增大,土体的失稳由开始的两部分组成逐渐转变为一部分组成,且支护力也逐渐减小;无支撑长度与开挖面支护力呈线性增加,同时缩短了土体进入失稳阶段的时间;随着内摩擦角的增大,极限支护力逐渐减小并趋于稳定值,但并未对失稳模式产生影响。

关键词：隧道离心试验无支撑长度开挖面支护力失稳模式

Intestinal microbiota and juvenile idiopathic arthritis:current understanding and future prospective

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World Journal of Pediatrics 2021年第1期17卷 40-51页

作者： le Xin Feng He Sen Li Zhi-Xuan Zhou Xiao-lin Ma Gynecological Minimal Invasive Center Beijing Obstetrics and Gynecology HospitalCapital Medical UniversityBeijingChina Department of Biochemistry and Immunology Capital Institute of PediatricsYabao Road No.2Chaoyang DistrictBeijingChina Department of Rheumatology Capital Institute of PediatricsBeijingChina

Background Juvenile idiopathic arthritis(JIA)characterized by arthritis of unknown origin is the most common childhood chronic rheumatic disease,caused by both host genetic factors and environmental triggers.Recent evidence has mounted to focus on the intestinal microbiota,a potentially recognized set of environmental triggers affecting JIA development.Here we offer an overview of recently published animal and human studies that support the impact of intestinal microbiota in JIA.Data sources We searched PubMed for animal and human studies publications with the search terms"intestinal microbiota or gut microbiota"and"juvenile idiopathic arthritis or juvenile chronic arthritis or juvenile rheumatoid arthritis or childhood rheumatoid arthritis or pediatric rheumatoid arthritis".Results Several comparative studies have demonstrated that intestinal microbial alterations might be triggers in disease pathogenesis.Alternatively,a slice of studies has suggested environmental triggers in early life might disrupt intestinal microbial colonization,including cesarean section,formula feeding,and antibiotic exposure.Aberrant intestinal microbiota may influence the development of JIA by mediating host immune programming and by altering mucosal permeability.Conclusions Specific microbial factors may contribute to the pathogenesis of JIA.Intensive studies,however,are warranted to investigate the causality between intestinal dysbiosis and JIA and the mechanisms behind these epidemiologic relationships.Studies are also needed to design the best interventional administrations to restore balanced intestinal microbial communities.

关键词： Antibiotic exposure Cesarean section Immune system reprogramming Intestinal microbiota Juvenile idiopathic arthritis

A simple way to visualize detailed phylogenetic tree of huge genome-wide SNP data constructed by SNPhylo

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Journal of Integrative Agriculture 2018年第9期17卷 1972-1978页

作者： YANG Hai-long DONG le WANG Hui LIU Chang-lin LIU Fang XIE Chuan-xiao National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences Chinese Academy of Agricultural Sciences

Phylogenetic trees based on genome-wide single nucleotide polymorphisms （SNPs） among diverse inbreds could provide valuable and intuitive information for breeding and germplasm management in crops. As a result of sequencing technology developments, a huge amount of whole genome SNP data have become available and affordable for breeders. However, it is a challenge to perform quick and reliable plotting based on the huge amount of SNP data. To meet this goal, a visualization pipeline was developed and demonstrated based on publicly available SNP data from the current important maize inbred lines, including temperate, tropical, sweetcorn, and popcorn. The detailed phylogenetic tree plotted by our pipeline revealed the authentic genetic diversity of these inbreds, which was consistent with several previous reports and indicated that this straightforward pipeline is reliable and could potentially speed up advances in crop breeding.

关键词： phylogenetic tree SNP genetic diversity

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跨断层地震动及其对桥梁结构影响研究进展

中国公路学报 2023年第1期36卷 80-96页

作者：宗周红林元铮林津黎雅乐东南大学爆炸安全防护教育部工程研究中心江苏南京211189 东南大学土木工程学院江苏南京211189 江苏开放大学建筑工程学院江苏南京210036

与常规地震动激励的情况相比,跨断层地震动作用下桥梁结构具有更复杂的动力响应、更大的地震需求以及更严重的地震损伤。伴随着川藏铁路等超级基础工程的开工建设,越来越多的桥梁具有跨越潜在断层的风险,相关研究亟待开展。从跨断层桥... 详细信息

与常规地震动激励的情况相比,跨断层地震动作用下桥梁结构具有更复杂的动力响应、更大的地震需求以及更严重的地震损伤。伴随着川藏铁路等超级基础工程的开工建设,越来越多的桥梁具有跨越潜在断层的风险,相关研究亟待开展。从跨断层桥梁震害出发,首先阐述了近/跨断层地震动的基本特性并介绍了相关模拟方法,然后综述了跨断层桥梁抗震分析理论、数值模拟和模型试验等研究的相关进展,进而归纳了考虑跨断层地震动作用的应对策略。结果表明:现有的跨断层地震动模拟方法合理可行,但存在一定的应用条件和改进空间;跨断层桥梁研究对象大多为中小跨径梁桥,其地震响应和损伤破坏模式受断层类型、跨越位置、跨越角度、永久位移等多因素影响;针对跨断层桥梁的减隔震和防落梁限位措施等技术得到初步发展。最后展望了未来跨断层桥梁抗震研究的发展方向,主要包括:发展更为精确、高效的跨断层地震动模拟技术;开展大跨径桥梁的跨断层振动台台阵试验及倒塌数值模拟研究;突破跨断层桥梁振动台台阵试验技术瓶颈;明确跨断层地震动参数对不同类型桥梁结构地震损伤机理的影响规律;进一步发展相应的减隔震技术、防落梁措施以及韧性防控技术,并进行试验验证等。

关键词：桥梁工程抗震性能综述跨断层地震动模拟地震响应地震损伤应对策略

The complete mitochondrial genome of the grey bamboo shark (Chiloscyllium griseum) (Orectolobiformes: Hemiscylliidae): genomic characterization and phylogenetic application

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Acta Oceanologica Sinica 2013年第4期32卷 59-65页

作者： CHEN Xiao AI Weiming YE le WANG Xuehui lin Chongwen YANG Shengyun College of Fisheries Ocean University of China Zhejiang Key Laboratory of Exploitation and Preservation of Coastal Bio-Resource Zhejiang Mariculture Research Institute Department of Marine Science School of Life Science Wenzhou Medical College South China Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Laboratory of Marine Biodiversity and Global Change College of Ocean and Earth Sciences Xiamen University

The complete mitochondrial genome of the grey bamboo shark, Chiloscyllium griseum （Orectolobiformes： HemiscyUiidae） was obtained, with a total of 16 755 base pairs （bp）. The mitogenome encoded 13 protein- coding genes, two ribosomal RNAs, 22 transfer RNAs and a noncoding control region, a gene arrangement identical to the most common type found in vertebrates. All tRNA sequences were folded into typical clover- leaf secondary structure with the exception of tRNA-Ser2, in which the DHU arm stem was replaced with 12 unpaired nucleotides and formed a simple loop. In the control region, the putative termination-associated sequences （TAS） with hairpin-loop structure and the conserved sequence blocks （CSB） I-III were identified and considered to be associated with the replication and transcription of mtDNA. No repeat motifs were found in the mitogenome of C. griseum. On the basis of the mitogenomic data available in the Class Chon- drichthyes from both Genbank and this study, and the phylogenetic analyses using maximum likelihood （ML） and Bayesian inference （BI） methods, the results strongly support the basal division between batoids and sharks and the monophyly of the Superorder Galeomorphii, and confirm the phylogenetic position of C. griseum in the Subclass Elasmobranchii. This study suggests that the mitogenomic data are more robust for reconstructing phylogenetic relationships than individual genes in the Elasmobranchii.

关键词： mitochondrial genome Chiloscyllium griseum Chondrichthyes phylogeny carpet shark,Galeomorphii