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细菌内抗菌药物积累测定方法研究进展

中国畜牧兽医 2025年第1期52卷 451-460页

作者：孙丽谭冰冰李长琼袁欣怡潘源虎华中农业大学国家兽药残留基准实验室武汉430070

抗菌药是治疗细菌感染的关键药物,也是现代医学中至关重要的基础药物之一。但当前现有抗菌药物耐药性日益严重以及新抗菌药物发现渠道不足的问题已受到关注并亟需解决。抗菌药透过细菌的外膜屏障且在作用靶点位置蓄积至有效浓度才能发... 详细信息

抗菌药是治疗细菌感染的关键药物,也是现代医学中至关重要的基础药物之一。但当前现有抗菌药物耐药性日益严重以及新抗菌药物发现渠道不足的问题已受到关注并亟需解决。抗菌药透过细菌的外膜屏障且在作用靶点位置蓄积至有效浓度才能发挥抗菌作用。因此,测定细菌内抗菌药物的含量,有助于建立药物在细菌内蓄积特性与其结构之间的关系,为新型抗菌药物设计提供指导。目前,已有多种检测方法被开发用于细菌内抗菌药物浓度测定。笔者首先简要介绍了革兰阳性菌和革兰阴性菌细胞膜的结构差异,再从早期的放射性测定法、荧光测定法及基于质谱开发的新型方法(包括液相色谱串联质谱检测法、固相萃取-质谱测定法、纳米流体-质谱联用技术、飞行时间二次离子质谱和生物探针与质谱的联合应用)入手,介绍各检测方法及当前的应用,并总结概述了上述方法的优缺点,对其今后的发展进行了展望,以期为后续细菌内抗菌药物积累测定方法的应用提供建议,为设计和发现新的抗菌药物尤其是抗革兰阴性菌新药提供参考。

关键词：抗菌药物抗菌药物摄取检测方法细胞内积累亚细胞定位

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Exact Geometric Relationships, Symmetry Breaking and Structural Stability for Single-Walled Carbon Nanotubes

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Nano-Micro Letters 2011年第4期3卷 228-235页

作者： Tong Zhang Ze Shuai yuan Li Hao tan Research Center for Solid Mechanics Beihang University

We pioneered a study about how the geometric relationship of single-walled carbon nanotubes(SWCNT) is influenced by curvature factor and non-planar geometry factor in cylindrical coordinate system based on the assumption of complete symmetry. The bond length and angle of every carbon-carbon bonds are determined by using the principle of the minimum energy. The results of the paper include(1) From the calculation result, the symmetry breaking appears for chiral carbon nanotubes, while the part symmetry appears for achiral carbon nanotubes with increasing curvature.(2) The synergistic effect of bond lengths and bond angles is first found.(3) We conclude that the influence of non-planar geometry factor can be completely ignored on bond lengths and bond angles when the curvature parameter has been included in the model.(4)The two fractal dimensions are given from the nanoscale to the macroscale for zigzag topology and armchair topology respectively. Fractal dimensions of SWCNT show special characteristics, varying with the length of SWCNT until the lengths approach infinity. The close and inevitable correlations among curvature, symmetry breaking and stability of SWCNTs can be summed up as: the increase of curvature causes symmetry breaking,and such symmetry breaking will further reduce the structural stability.

关键词： Geometry Structural Stability Symmetry Breaking Fractal Dimension

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中低水头混流式水轮机涡带区压力脉动研究

人民长江 2025年第2期56卷 158-166,182页

作者：叶长红袁玲丽谭军龚莉刘芮麟邓祥平贵州乌江水电开发有限责任公司乌江渡电厂贵州遵义563104 东方电机有限公司研发中心四川德阳618000

当混流式水轮机在涡带区工况即部分负荷运行时,诱发的压力脉动偏大,易引起机组各部件的振动、噪声甚至出力波动,影响机组的安全稳定运行。以大型中低水头混流式水轮机为研究对象,针对模型试验中出现的涡带区压力脉动突然增大及振动噪声... 详细信息

当混流式水轮机在涡带区工况即部分负荷运行时,诱发的压力脉动偏大,易引起机组各部件的振动、噪声甚至出力波动,影响机组的安全稳定运行。以大型中低水头混流式水轮机为研究对象,针对模型试验中出现的涡带区压力脉动突然增大及振动噪声现象,进行模型试验和三维全流道非定常数值计算(CFD)研究。结果表明:引起涡带区压力脉动突增的原因是1.35倍转频的频率成分,由粗且不稳定的尾水涡带引起;优化转轮和补气能够破坏粗且不稳定的尾水涡带,从而消除1.35倍转频的频率成分,大大降低涡带区的压力脉动幅值;匹配不同的泄水锥能够减弱尾水涡带的强度(使涡带稍微变细),涡带区的压力脉动幅值有所下降,但未能破坏涡带的形状,不能消除1.35倍转频的频率成分。研究成果为改善涡带区压力脉动提供了新的思路,在实际工程中可根据实际情况采用合适的措施。

关键词：混流式水轮机涡带区压力脉动模型试验数值模拟

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A Joint Estimation Method of SOC and SOH for Lithium-ion Battery Considering Cyber-Attacks Based on GA-BP

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Computers, Materials & Continua 2024年第9期80卷 4497-4512页

作者： Tianqing yuan Na Li Hao Sun Sen tan Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology Ministry of EducationNortheast Electric Power UniversityJilin132012China Department of Electrical Engineering Northeast Electric Power UniversityJilin132012China College of Information and Control Engineering Jilin Institute of Chemical TechnologyJilin132022China Center for Research on Microgrids Department of EnergyAalborg UniversityAalborg9220Denmark

To improve the estimation accuracy of state of charge(SOC)and state of health(SOH)for lithium-ion batteries,in this paper,a joint estimation method of SOC and SOH at charging cut-off voltage based on genetic algorithm(GA)combined with back propagation(BP)neural network is proposed,the research addresses the issue of data manipulation resulting ***,anomalous data stemming fromcyber-attacks are identified and eliminated using the isolated forest algorithm,followed by data ***,the incremental capacity(IC)curve is derived fromthe restored data using theKalman filtering algorithm,with the peak of the ICcurve(ICP)and its corresponding voltage serving as the health factor(HF).Thirdly,the GA-BP neural network is applied to map the relationship between HF,constant current charging time,and SOH,facilitating the estimation of SOH based on ***,SOC estimation at the charging cut-off voltage is calculated by inputting the SOH estimation value into the trained model to determine the constant current charging time,and by updating the maximum available *** show that the root mean squared error of the joint estimation results does not exceed 1%,which proves that the proposed method can estimate the SOC and SOH accurately and stably even in the presence of false data injection attacks.

关键词： Lithium-ion batteries state of charge state of health cyber-attacks genetic algorithm back propagation neural network

Artificial Nucleotide-containing Aptamers Used in Tumor Therapy

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Chemical Research in Chinese Universities 2020年第2期36卷 164-170页

作者： QIN Xmyuan SU yuanye tan Jie yuan Quan Institute of Chemical Biology and Nanomedicine(ICBN) State Key Laboratory of Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringCollege of BiologyHunan UniversityChangsha 410082P.R.China Key Laboratory of Analytical Chemistry for Biology and Medicine Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072P.R.China

The high pharmaceutical cost and multi-drug resistance in tumor therapeutic agents hinder the further application of chemotherapy in tumor *** modified nucleic acid aptamers have the advantages of high binding affinity,programmability,and easy ***,the rational design of artificial modified aptamers is expected to provide a versatile platform for the optimization of chemotherapy *** this review,we summarize the modification strategies and the application of the artificial modified nucleotide-containing aptamers,aiming to provide a promising step toward aptamer-related chemotherapeutic agents.

关键词： Aptamer Artificial nucleotide Functional nucleic acid

An address regional tessellation method for spatial subdivision and geocoding in digital earth system

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International Journal of Digital Earth 2015年第10期8卷 825-839页

作者： tan Ningsheng Yang Chongjun Yang LiuZhong Liu yuan State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingChina Graduate School University of Chinese Academy of SciencesBeijingChina Urban-Rural Planning Management Center Ministry of Housing and Urban-Rural Development of the People’s Republic of ChinaBeijingChina

With the increased use of locational information,spatial location referencing and coding methods have become much more important to the mining of both geographical and nongeographical data in digital earth ***,current methods of geocoding,based on reverse lookup of coordinates for a given address,have proven too lossy with respect to administrative and socioeconomic *** paper proposes a spatial subdivision and geocoding model based on spatial address regional tessellation(SART).Given a hierarchical address object definition,and based on the‘region of influence’characteristics of an address,SART creates multiresolution spatial subdivisions by irregular and continuous address *** model reflects most of the geographical features and many of the social and economic implications for a given *** also better reflects the way people understand addresses and spatial *** also propose an appropriate method of geocoding for standard addresses(SART-GC).The codes generated by this method can record address footprints,hierarchical relationships,and spatial scales in a single data ***,by applying our methods to the Shibei District of Qingdao,we demonstrate the suitability of SART-GC for multi-scale spatial information representation in digital earth systems.

关键词： address spatial tessellation spatial reference geocoding digital earth

Creative design inspired by biological knowledge:Technologies and methods

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Frontiers of Mechanical Engineering 2019年第1期14卷 1-14页

作者： Runhua tan Wei LIU Guozhong CAO yuan SHI School of Mechanical Engineering Hebei University of TechnologyTianjin 300401China National Engineering Research Center for Technological Innovation Method and Tool Hebei University of TechnologyTianjin 300401China Department of Mechanical Engineering Politecnico di Mila noMilan 20156Italy

Biological knowledge is becoming an important source of inspiration for developing creative solutions to engineering design problems and even has a huge potential in formulating ideas that can help firms compete successfully in a dynamic *** identify the technologies and methods that can facilitate the development ofbiologically inspired creative designs,this research briefly reviews the existing biological-knowledge-based theories and methods and examines the application of biological-knowledge-inspired designs in various ***,this research thoroughly examines the four dimensions of key technologies that underlie the biologically inspired design(BID)*** research then discusses the future development trends of the BID process before presenting the conclusions.

关键词： creative design biologically inspired methods key technologies

Mechanism of mitochondrial oxidative phosphorylation disorder in male infertility

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中华医学杂志(英文版) 2025年第04期

作者： Meng Kai Liu Qian Qin Yiding Qin Wenjie Zhu Ziming Sun Longlong Jiang Mingchao Adu-Amankwaah Joseph Gao Fei tan Rubin yuan Jinxiang Collaborative Innovation Center for Birth Defect Research and Transformation of Shandong Province Jining Medical University Jining Shandong China Lin He’s Academician Workstation of New Medicine and Clinical Translation Jining Medical University Jining Shandong China College of Basic Medical Jining Medical University Jining Shandong China College of Second Clinical Medicine Jining Medical University Jining Shandong China College of Basic Medical Xuzhou Medical University Xuzhou Zhejiang China State Key Laboratory of Stem Cell and Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing China

Male infertility has become a global concern, accounting for 20-70% of infertility. Dysfunctional spermatogenesis is the most common cause of male infertility; thus, treating abnormal spermatogenesis may improve male infertility and has attracted the attention of the medical community. Mitochondria are essential organelles that maintain cell homeostasis and normal physiological functions in various ways, such as mitochondrial oxidative phosphorylation (OXPHOS). Mitochondrial OXPHOS transmits electrons through the respiratory chain, synthesizes adenosine triphosphate (ATP), and produces reactive oxygen species (ROS). These mechanisms are vital for spermatogenesis, especially to maintain the normal function of testicular Sertoli cells and germ cells. The disruption of mitochondrial OXPHOS caused by external factors can result in inadequate cellular energy supply, oxidative stress, apoptosis, or ferroptosis, all inhibiting spermatogenesis and damaging the male reproductive system, leading to male infertility. This article summarizes the latest pathological mechanism of mitochondrial OXPHOS disorder in testicular Sertoli cells and germ cells, which disrupts spermatogenesis and results in male infertility. In addition, we also briefly outline the current treatment of spermatogenic malfunction caused by mitochondrial OXPHOS disorders. However, relevant treatments have not been fully elucidated. Therefore, targeting mitochondrial OXPHOS disorders in Sertoli cells and germ cells is a research direction worthy of attention. We believe this review will provide new and more accurate ideas for treating male infertility.

关键词： Mitochondria Oxidative phosphorylation Spermatogenesis Male infertility

Self-powered macroscopic Brownian motion of spontaneously running liquid metal motors

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Science Bulletin 2015年第13期60卷 1203-1210页

作者： Bin yuan Sicong tan Yixin Zhou Jing Liu Key Laboratory of Cryogenics Technical Institute of Physics and Chemistry Chinese Academy of Sciences Department of Biomedical Engineering School of MedicineTsinghua University

We disclosed the interiorly driven macroscopic Brownian motion behavior of self-powered liquid metal motors. Such tiny motors in millimeter scale move randomly at a velocity magnitude of centimeters per second in aqueous alkaline solution, well resembling the classical Brownian motion. However, unlike the existing phenomena, where the particle motions were caused by collisions from the surrounding molecules, the current random liquid metal motions are internally enabled and self-powered, along with the colliding among neighboring motors, the substrate and the surrounding electrolyte molecules. Through uniformly dissolving only 1% （mass percentage） A1 into GaInl0, many tiny motors can be quickly fabricated and activated to take the Brownian-like random motions. Further, we introduced an experimental approach of using optical image contrast, which works just like the Wilson cloud chamber, to distinctively indicate the motor trajectory resulted from the generated hydrogen gas stream. A series of unusual complicated multi-phase fluid mechanics phenomena were observed. It was also identified that the main driving factor of the motors comes from the H2 bubbles generated at the bottom of these tiny motors, which is different from the large size self-fueled liquid metal machine. Several typical mechanisms for such unconventional Brownian-like motion phenomena were preliminarily interpreted.

关键词： Self-powered Brownian motion . Liquidmetal motor - Al-Ga-In alloy . Bubble repulsion .Optical image contrast

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