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Systems Microbiology and Biomanufacturing 2022年第3期2卷 523-532页

作者： M.Venkateswar Reddy alexander steinbüchel Institut für Molekulare Mikrobiologie und Biotechnologie Westfälische Wilhelms-Universität Münster48149 MünsterGermany Center for Biotechnology and Interdisciplinary Studies Rensselaer Polytechnic Institute1108th StreetTroyNY 12180USA Environmental Sciences Department King Abdulaziz UniversityJeddahSaudi Arabia

The bacterium Rhodococcus erythropolis MI2 uses 4,4´-dithiodibutyric acid(DTDB)as carbon source to synthesize polythioesters(PTE).The first step for the production of PTE using DTDB is catalyzed by an NADH:flavin oxidoreductase(nox)as it was previously shown in our laboratory,and the second step is catabolized by a putative luciferase-like monooxygenase(Llm).In the current study,experiments were carried out to identify the function of ***,the llm gene,which encodes for the Llm protein,was amplified from the genomic DNA of MI2 using polymerase chain reaction and expressed in Escherichia coli BL21 *** purification was done using His Spin Trap affinity *** assay was carried out using the purified protein and p-coumaric acid as substrate giving a specific activity of 1.6 U/mg protein for the purified *** responsible gene(llm)was deleted in the genome of MI2,and a single deletion mutant was subsequently ***,growth of the wild-type strain(MI2)and the mutant strain(MI2Δllm)were compared using DTDB or succinate as carbon *** the wild type was successfully grown with DTDB or succinate,the llm-negative mutant exhibited low grow with DTDB although it grows very well with succinate.

关键词： Deletion mutant Monooxygenase Polythioesters Protein purification Rhodococcus erythropolis MI2 4,4´-Dithiodibutyric acid(DTDB)

Ralstonia eutropha CH34酯酶基因的克隆和序列分析

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微生物学报 2001年第4期41卷 402-407页

作者：宋水山 alexander steinbchel 河北省科学院生物研究所石家庄050051 Institut fr Mikrobiologie

采用含α 乙酸萘酯和固兰RR的表面琼脂法从RalstoniaeutrophaCH34的基因文库中筛选酯酶基因estA ,对含有estA的 1 7kbDNA片段的核甘酸序列分析表明 ,该基因全长82 5bp,编码由 2 75个氨基酸组成的EstA蛋白 ,分子量为 30 785D。经推导氨... 详细信息

采用含α 乙酸萘酯和固兰RR的表面琼脂法从RalstoniaeutrophaCH34的基因文库中筛选酯酶基因estA ,对含有estA的 1 7kbDNA片段的核甘酸序列分析表明 ,该基因全长82 5bp,编码由 2 75个氨基酸组成的EstA蛋白 ,分子量为 30 785D。经推导氨基酸序列的同源性分析 ,发现EstA与参与芳香化合物代谢中间位裂解途径的水解酶有很高的同源性。

关键词： ReutrophaCH34 酯酶基因 DNA序列大肠杆菌克隆表达

重组大肠杆菌合成聚(3-巯基丙酸)和聚(3-羟基丁酸-3-巯基丙酸)的研究(英文)

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生物工程学报 2003年第2期19卷 195-199页

作者：刘双江 Tina Lütke-Eversloh alexander steinbüchel 中国科学院微生物研究所北京100080 Institute of Microbiology

利用Clostridiumacetobutylicum的丁酸激酶基因 (buk)和磷酸转丁酰基酶基因 (ptb) ,以及Thiocapsapfennigii的PHA合成酶基因 ,设计了一条能够合成多种聚羟基烷酸的代谢途径 ,用构建的质粒转化大肠杆菌 ,获得了重组大肠杆菌菌株。前期的... 详细信息

利用Clostridiumacetobutylicum的丁酸激酶基因 (buk)和磷酸转丁酰基酶基因 (ptb) ,以及Thiocapsapfennigii的PHA合成酶基因 ,设计了一条能够合成多种聚羟基烷酸的代谢途径 ,用构建的质粒转化大肠杆菌 ,获得了重组大肠杆菌菌株。前期的研究表明 ,在合适的前体物条件下 ,该重组大肠杆菌能够合成包括聚羟基丁酸、聚 (羟基丁酸戊酸 )等多种生物聚酯 [Liuandsteinb櫣ｃｈｅｌ,*** .Microbiol.6 6 :739 743]。利用该重组大肠杆菌 ,通过生物催化作用合成了 3 巯基丙酸的同型共聚酯 ,同时利用该重组大肠杆菌还获得了含 3 巯基丙酸单体的多种异型共聚物。实验首先研究了 3 巯基丙酸对大肠杆菌生长的影响 ,在此基础上优化了培养过程中添加 3 巯基丙酸的时机和浓度 ,结果表明 ,在实验的条件下 ,细胞合成聚 (3 巯基丙酸 )可达 6 7% (占细胞干重 ) ,合成聚 (3 羟基丁酸— 3 巯基丙酸 ) (分子中 3 巯基丙酸 :3 羟基丁酸 =3:1)可达 2 4 3%。实验进一步研究了同时或分别表达以上 3个基因的重组大肠杆菌合成聚合物的能力 ,结果表明只有当 3个基因同时表达时才能合成聚合物 ,说明 3个基因对合成过程是必须的 ,从而表明了合成途径是按照设计的路线进行的。还通过GC MS、GPC、IR等手段对合成的化合物进行了定性?

关键词：重组大肠杆菌聚3—巯基丙酸聚3—羟基丁酸—3—巯基丙酸生物合成聚羟基烷酸生物多聚物

Microglia:a promising therapeutic target in spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 454-463页

作者： Xiaowei Zha Guoli Zheng Thomas Skutella Karl Kiening Andreas Unterberg alexander Younsi Department of Neurosurgery Heidelberg University HospitalHeidelbergGermany Department of Neuroanatomy Institute for Anatomy and Cell BiologyHeidelberg UniversityHeidelbergGermany

Microglia are present throughout the central nervous system and are vital in neural repair,nutrition,phagocytosis,immunological regulation,and maintaining neuronal *** a healthy spinal cord,microglia are accountable for immune surveillance,however,when a spinal cord injury occurs,the microenvironment drastically changes,leading to glial scars and failed axonal *** this context,microglia vary their gene and protein expression during activation,and proliferation in reaction to the injury,influencing injury responses both favorably and unfavorably.A dynamic and multifaceted injury response is mediated by microglia,which interact directly with neurons,astrocytes,oligodendrocytes,and neural stem/progenitor *** a clear understanding of their essential nature and origin,the mechanisms of action and new functions of microglia in spinal cord injury require extensive *** review summarizes current studies on microglial genesis,physiological function,and pathological state,highlights their crucial roles in spinal cord injury,and proposes microglia as a therapeutic target.

关键词： astrocytes cytokines functional recovery immune regulation M1/M2 activation macrophages microglia neuroinflammation spinal cord injury therapy

Treating amyotrophic lateral sclerosis with allogeneic Schwann cell-derived exosomal vesicles: a case report

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Neural Regeneration Research 2025年第4期20卷 1207-1216页

作者： Pascal J.Goldschmidt-Clermont Aisha Khan George Jimsheleishvili Patricia Graham Adriana Brooks Risset Silvera alexander J.P.Goldschmidt Damien D.Pearse W.Dalton Dietrich Allan D.Levi James D.Guest Miller School of Medicine University of MiamiMiamiFLUSA Stem Cell Institute Miller School of MedicineUniversity of MiamiMiamiFLUSA The Miami Project to Cure Paralysis Miller School of MedicineUniversity of MiamiMiamiFLUSA Alzady International LLC MiamiFLUSA Neurological Surgery Miller School of MedicineUniversity of MiamiMiamiFLUSA

Schwann cells are essential for the maintenance and function of motor neurons,axonal networks,and the neuromuscular *** amyotrophic lateral sclerosis,where motor neuron function is progressively lost,Schwann cell function may also be ***,important signaling and potential trophic activities of Schwann cell-derived exosomal vesicles have been *** case report describes the treatment of a patient with advanced amyotrophic lateral sclerosis using serial intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles,marking,to our knowledge,the first instance of such *** 81-year-old male patient presented with a 1.5-year history of rapidly progressive amyotrophic lateral *** initial diagnosis,the patient underwent a combination of generic riluzole,sodium phenylbutyrate for the treatment of amyotrophic lateral sclerosis,and *** patient volunteered to participate in an FDA-approved single-patient expanded access treatment and received weekly intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles to potentially restore impaired Schwann cell and motor neuron *** confirmed that cultured Schwann cells obtained from the amyotrophic lateral sclerosis patient via sural nerve biopsy appeared impaired(senescent)and that exposure of the patient’s Schwann cells to allogeneic Schwann cell-derived exosomal vesicles,cultured expanded from a cadaver donor improved their growth capacity in *** a period of observation lasting 10 weeks,during which amyotrophic lateral sclerosis Functional Rating Scale-Revised and pulmonary function were regularly monitored,the patient received weekly consecutive infusions of 1.54×1012(×2),and then consecutive infusions of 7.5×1012(×6)allogeneic Schwann cell-derived exosomal vesicles diluted in 40 mL of Dulbecco’s phosphate-buffered *** of the infusions were associated with adverse events such as infusion reactions(allergic or otherwise)or

关键词： allogeneic amyotrophic lateral sclerosis exosomes infusion neuromuscular junction Schwann cell

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Gushing metal chain

Frontiers of Mechanical Engineering 2016年第1期11卷 95-100页

作者： alexander BELYAEV alexander SUKHANOV alexander TSVETKOV Institute of Applied Mathematics and Mechanics Saint-Petersburg Polytechnic University St. Petersburg 195251 Russia

This article addresses the problem in which a chain falls from a glass from some height. This phenomenon demonstrates a paradoxical rise of the chain over the glass. To explain this effect, an initial hypothesis and an appropriate theory are proposed for calculating the steady fall parameters of the chain. For this purpose, the modified Cayley ＇s problem of falling chain given its rise due to the centrifugal force of upward inertia is solved. Results show that the lift caused by an increase in linear density at the part of chain where it is being bent （the upper part） is due to the convergence of the chain balls to one another. The experiments confirm the obtained estimates of the lifting chain.

关键词： chain fountain Meshchersky equation,Cayley's problem

Computer study of the formation of water-ammonia clusters and their dielectric properties

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Chinese Physics B 2013年第7期22卷 167-172页

作者： alexander Galashev Institute of Industrial Ecology Ural BranchRussian Academy of Sciences

The absorption of one to six ammonia molecules by the （H2O）50 cluster is studied by the molecular dynamics method under near-atmospheric conditions. The capture of NH 3 molecules by a water cluster produces an increase in the integrated intensity of IR absorbance, substantially decreases emission power in the frequency range of 0≤ω≤3500cm-1,and transforms a continuous reflectance spectrum into a banded one. Adsorption of ammonia molecules by water clusters greatly diminishes the number of electrons that are active with respect to electromagnetic radiation. The present results are also compared with the experimental findings wherever available.

关键词： ammonia water cluster infrared absorption spectra molecular dynamics

Chargino Production via Z^0-Boson Decay in a Strong Electromagnetic Field

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Chinese Physics Letters 2016年第3期33卷 17-19页

作者： alexander Kurilin Moscow Technological Institute on leave from Moscow State Open Pedagogical University

In the framework of MSSM the probability of Z0-boson decay to chaxginos in a strong electromagnetic field, Z X＋X-, is analyzed. The method of calculations employs exact solutions of relativistic wave equations for charginos in a crossed electromagnetic field. Analytic expression for the decay width is obtained at an arbitrary value of the parameter which characterizes the external-field strength Fμv and Z%boson momentum qv. The process Z0→ X＋X- is forbidden in a vacuum for the case of relatively heavy charginos： Mx±mz/2. However, in an intense electromagnetic background this reaction could take place in the region of superstrong fields （x〉1）.

关键词： of on is in Chargino Production via Z~0-Boson Decay in a Strong Electromagnetic Field for

Use of GIS technology and cellular automata for modeling multiple socio-economic scenarios of regional spatial development and inter-regional cooperation

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Geo-Spatial Information Science 2023年第1期26卷 71-93页

作者： Igor Musikhin alexander Karpik Department of Photogrammetry and Remote Sensing Siberian State University of Geosystems and TechnologiesNovosibirskRussia Department of Space and Physical Geodesy Siberian State University of Geosystems and TechnologiesNovosibirskRussia

The advancement of effective spatial planning to support sustainable development and interregional cooperation has become an issue of serious concern for regional *** planning research helps to identify economic clusters and analyze their changing spatial patterns,which is important for understanding regional economic space dynamics and poten-tial inter-regional *** support decision-makers in the development of efficient plans of spatial development encompassing the identification of the best-suited territories,a combined Geographic Information System(GIS)based approach to interpret qualitatively expressed multiple socio-economic scenarios in quantitative map-based terms of graded suitability,and a formalized approach to the socio-economic evaluation of the territory is *** on GIS technology coupled with integrated cellular automata decision analysis techniques,the study provides a method that performs socio-economic assessment of the study area according to the generated scenarios of regional spatial and socio-economic *** proposed method is applied to Primorsky and Khabarovsk Krais,located in the Russian Far ***-economic scenarios of spatial development initiated by investors and regional authorities were assessed and *** generated socio-economic scenar-ios illustrate how the unified set of spatial and socio-economic variables can be linked and used to gain insights into inter-regional socio-economic and spatial *** application results demonstrate the advantage of the proposed method in identifying the best-suited unit areas for targeted regional development.

关键词： Geographic Information System(GIS) spatial development socioeconomic scenarios interregional cooperation open source software Cellular Automata(CA)

Volcanic Ash in the Atmosphere and Risks for Civil Aviation:A Study in European Crisis Management

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International Journal of Disaster Risk Science 2013年第1期4卷 9-19页

作者： David alexander Institute for Risk and Disaster Reduction University College London London WC1E 6BT United Kingdom

This paper uses the eruption of the Icelandic volcano Eyjafjallaj?kull in April and May 2010 as a case study of disruption to civil aviation by airborne ash, with emphasis on risk management aspects. Severe curtailment of flights over much of Europe took place during the crisis, which lasted for slightly more than one week. More than 8.5 million passengers were stranded and commerce was profoundly affected. The United Kingdom was one of the worst impacted countries and took the lead in managing the crisis. The paper considers elements of the decision-making process that formed the basis of the UK Government’s emergency response. It examines the relations between science, governance, and economi c imperatives. Physical thresholds guiding decisions to restrict airspace were defined somewhat arbitrarily, which may have increased disruption. A damaging form of risk aversion prevailed at certain points in the crisis. Lack of preexisting procedures and planning meant that the response to dynamically changing meteorological conditions had to be improvised. At the same time, lack of integration between different modes in the European transportation system meant that had the crisis continued any longer there would have been severe problems in moving stranded people and commodities, as well as soaring economic losses. Eruptions similar to or more serious than that of Eyjafjallaj?kull are perfectly possible in Europe in the not-too-distant future.

关键词： Atmosphere aviation meteorological