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Spontaneous mutations and mutational responses to penicillin treatment in the bacterial pathogen Streptococcus pneumoniae D39

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Marine Life Science & Technology 2024年第2期6卷 198-211页

作者： Wanyue Jiang Tongtong Lin Jiao Pan Caitlyn eRivera Clayton Tincher Yaohai Wang Yu Zhang Xiang Gao Yan Wang Ho‑Ching T.Tsui malcolm e.winkler Michael Lynch Hongan Long Institute of evolution and Marine Biodiversity KLMMEOcean University of ChinaQingdao 266003China Laboratory for Marine Biology and Biotechnology Laoshan LaboratoryQingdao 266237China Department of Biology Indiana UniversityBloomingtonIN 47405USA School of Mathematics Science Ocean University of ChinaQingdao 266000China State Key Laboratory of Microbial Technology Microbial Technology InstituteSchool of Life ScienceShandong UniversityQingdao 266237China Biodesign Center for Mechanisms of evolution Arizona State UniversityTempeAZ 85281USA

Bacteria with functional DNA repair systems are expected to have low mutation rates due to strong natural selection for genomic ***,our study of the wild-type Streptococcus pneumoniae D39,a pathogen responsible for many common diseases,revealed a high spontaneous mutation rate of 0.02 per genome per cell division in mutation-accumulation(MA)*** rate is orders of magnitude higher than that of other non-mutator bacteria and is characterized by a high mutation bias in the A/T *** high mutation rate may have resulted from a reduction in the overall efficiency of selection,conferred by the tiny effective population size in *** line with this,*** D39 also exhibited the lowest DNA mismatch-repair(MMR)efficiency among *** with the antibiotic penicillin did not elevate the mutation rate,as penicillin did not induce DNA damage and *** lacks a stress response *** findings suggested that the MA results are applicable to within-host scenarios and provide insights into pathogen evolution.

关键词： Neutral evolution Mutation spectrum Antibiotics DNA mismatch repair Oxidative damage repair

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General Solutions of First-Order Algebraic ODes in Simple Constant extensions

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系统科学与复杂性学报:英文版 2023年第4期36卷 1769-1788页

作者： MITTeRAMSKOGLeR Johann Josef winkler Franz Research Institute for Symbolic Computation(RISC) Johannes Kepler Universität LinzA-4040 LinzAustria

If a first-order algebraic ODe is defined over a certain differential field,then the most elementary solution class,in which one can hope to find a general solution,is given by the adjunction of a single arbitrary constant to this *** of this type give rise to a particular kind of generic point—a rational parametrization—of an algebraic curve which is associated in a natural way to the ODe’s defining *** for the opposite direction,we show that a suitable rational parametrization of the associated curve can be extended to a general solution of the ODe if and only if one can find a certain automorphism of the solution *** automorphisms are determined by linear rational functions,i.e.,Möbius *** properties of rational parametrizations,in combination with the particular shape of such automorphisms,lead to a number of necessary conditions on the existence of general solutions in this solution ***,the desired linear rational function can be determined by solving a comparatively simple differential system over the ODe’s field of *** results hold for arbitrary differential fields of characteristic zero.

关键词： Algebraic curve algebraic differential equation general solution Möbius transformation rational parametrization

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*** and exploring Lineage Data as a Service

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Data Intelligence 2022年第2期4卷 226-242页

作者： Alessandro Spinuso malcolm Atkinson Federica Magnoni Koninklijk Nederlands Meteorologisch Instituut De BiltUtrecht 3731 GAThe Netherlands University of edinburgh EdinburghEdinburgh EH89ABUnited Kingdom Istituto Nazionale Geofisica e Vulcanologia RomeLazio 00143Italy

We present a set of configurable Web service and interactive tools,s-ProvFlow,for managing and exploiting records tracking data lineage during workflow *** facilitates detailed analysis of single *** helps users manage complex tasks by exposing the relationships between data,people,equipment and workflow runs intended to combine *** logical model extends the PROV standard to precisely record parallel data-streaming *** metadata handling encourages users to capture the application context by specifying how application attributes,often using standard vocabularies,should be *** metadata records immediately help productivity as the interactive tools support their use in selection and bulk *** rapidly appreciate the power of the encoded semantics as they reap the *** improves the quality of provenance for users and *** in turn facilitates analysis of collections of runs,enabling users to manage results and validate *** fosters reuse of data and methods and facilitates diagnostic investigations and *** present S-ProvFlow's use by scientists,research engineers and managers as part of the DARe hyper-platform as they create,validate and use their data-driven scientific workflows.

关键词： Provenance Productivity Workflows Human-in-the-loop Visualisation

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Stochastic Runge-Kutta–Munthe-Kaas Methods in the Modelling of Perturbed Rigid Bodies

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Advances in Applied Mathematics and Mechanics 2022年第2期14卷 528-538页

作者： Michelle Muniz Matthias ehrhardt Michael Günther Renate.winkler Institute of Mathematical Modelling Analysis and Computational Mathematics(IMACM)Applied Mathematics and Numerical AnalysisBergische Universität WuppertalGaußstraße 2042119 WuppertalGermany

In this paper we present how nonlinear stochastic Itˆo differential equations arising in the modelling of perturbed rigid bodies can be solved numerically in such a way that the solution evolves on the correct *** this end,we formulate an approach based on Runge-Kutta–Munthe-Kaas(RKMK)schemes for ordinary differ-ential equations on ***,we provide a proof of the mean-square convergence of this stochastic version of the RKMK schemes applied to the rigid body problem and illustrate the effectiveness of our proposed schemes by demonstrating the structure preservation of the stochastic RKMK schemes in contrast to the stochastic Runge-Kutta methods.

关键词： Stochastic Runge-Kutta method Runge-Kutta–Munthe-Kaas scheme nonlinear Itˆo SDes rigid body problem

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effect of operating pressure on the performance of THAI-CAPRI in situ combustion and in situ catalytic process for simultaneous thermal and catalytic upgrading of heavy oils and bitumen

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Petroleum Research 2022年第2期7卷 155-164页

作者： Muhammad Rabiu Ado malcolm Greaves Sean P.Rigby Department of Chemical engineering College of EngineeringKing Faisal UniversityP.O.Box:380Al-Ahsa31982Saudi Arabia Department of Chemical and environmental engineering University of NottinghamUniversity ParkNottinghamNG72RDUK Department of Chemical engineering University of BathClaverton DownBathBA27AYUK

According to the analysis of the 2020 estimates of the International energy Agency(2020),the world will require up to 770 billion barrels of oil from now to ***,based on the British Petroleum(BP)statistical review of world energy 2020,the world-wide total reserve of the conventional light oil is only 520.2 billion barrels as at the end of *** implies that the remaining 249.8 billion barrels of oil urgently needed to ensure a smooth transition to a decarbonised global energy and economic systems is provided must come from unconventional oils(*** oils and bitumen)*** heavy oils and bitumen are very difficult to produce and the current commercial production technologies have poor efficiency and release large quantities of greenhouse ***,these resources should ideally be upgraded and produced using technologies that have greener *** is where the energy-efficient,environmentally friendly,and self-sustaining THAI-CAPRI coupled in situ combustion and in situ catalytic upgrading process comes ***,the novel THAI-CAPRI process is trialled only once at field and it has not gained wide recognition due to poor understanding of the optimal design parameters and ***,this work reports the first ever results of investigations of the effect of operating pressure on the performance of the THAI-CAPRI *** experimental scale numerical models of the process based on Athabasca tar sand properties were run at pressures of 8000 kPa and 500 kPa respectively using CMG *** study has shown that the higher the operating pressure,the larger the API gravity and the higher the cumulative volume of high-quality oil is produced(i.e.a 2300 cm3 of z24 oAPI oil produced at 8000 kPa versus the 2050 cm3 of z17.5 oAPI oil produced at 500 kPa).The study has further shown that despite presence of annular catalyst layer,the THAI-CAPRI process operates ***,it is found that a more stable and safer operation of th

关键词： Toe-to-heel air injection(THAI) enhanced oil recovery(eOR) Reservoir simulation In situ combustion(ISC) Heavy oil/Bitumen/Tar sand In situ catalytic upgrading

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大肠杆菌生产的重组尿激酶的纯化及其特性

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生物工程进展 1987年第6期 39-48页

作者： Marjorie e.winkler 牛思敏

由大肠杆菌生产的重组尿激酶的高低分子量两种形式均已经重新折叠和提纯。对该蛋白质的低分子量形式作了比活性,氨基酸组成,氨基末端分析,羧基末端分析,胰蛋白酶图谱,抗体滴定,和色谱行为等特性描述。对高分子量形式作了比活性和色谱行... 详细信息

由大肠杆菌生产的重组尿激酶的高低分子量两种形式均已经重新折叠和提纯。对该蛋白质的低分子量形式作了比活性,氨基酸组成,氨基末端分析,羧基末端分析,胰蛋白酶图谱,抗体滴定,和色谱行为等特性描述。对高分子量形式作了比活性和色谱行为等特性描述。除缺少连接了天冬酰氨302碳水化合物外,在被试验的各个方面,重组尿激酶和天然尿激酶几乎完全相同。结果表明,由于大肠杆菌生产的可适当折叠,天然尿激酶上连接的碳水化合物在酶的催化活性中不起作用。

关键词：尿激酶血纤维蛋白低分子量色谱行为氨基末端比活性高分子量氨基酸组成催化活性蛋白水解

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Tungsten Promoted Ni/Al_2O_3 Catalysts for Carbon Dioxide Reforming of Methane to Synthesis Gas

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Chemical Research in Chinese Universities 2004年第4期20卷 470-477页

作者： Thomas Suhartanto Andrew P. e. York malcolm L. H. Green Wolfson Catalysis Centre Inorganic Chemistry Laboratory University of OxfordWolfson Catalysis Centre Inorganic Chemistry Laboratory University of OxfordWolfson Catalysis Centre Inorganic Chemistry Laboratory University of Oxford South Parks Road Oxford OX1 3QR UKSouth Parks Road Oxford OX1 3QR UKSouth Parks Road Oxford OX1 3QR UK

A series of tungsten promoted alumina supported nickel catalysts has been prepared for the carbon dioxide reforming of methane to synthesis gas. The catalysts have been characterized by means of XRD, TeM, and Laser Raman spectroscopy. It is shown that the addition of tungsten to the nickel catalyst can stabilize the catalyst and increase the resistance to carbon deposition. Adding a suitable amount of tungsten can also increase the catalyst activity to be close to that of supported noble metal catalysts. The carburisation of the tungsten modified nickel catalyst decreases the catalyst activity at lower reaction temperatures(effect on the catalyst performance at higher reaction temperatures. The alumina supported nickel catalyst modified by 0.67%(mass fraction) WO_3 has the equivalent equilibrium constant of the dry reforming reaction to that of alumina supported 5%(mass fraction) Ru at 873 K, and also has a lower activation energy for dry reforming than the latter.

关键词： Nickel catalyst Tungsten modifier CO_2 reforming Methane Syngas

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ZnO nanofluids-A potential antibacterial agent

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Progress in Natural Science:Materials International 2008年第8期18卷 939-944页

作者： malcolm Povey David York Procter Department of Food Science University of Leeds Leeds LS2 9JT UK Procter and Gamble Newcastle Technical Centre Newcastle-upon-Tyne NE12 9TS UK

In this work, ZnO nanofluids were produced by a medium mill with a pH value of about 7.2 and characterized by Nano-Sizer and SeM. After milling, ZnO nanofluids were formed with an average particle size of 198.4 nm. The ZnO nanofluids used for testing were stored for different periods (1-, 90- and 120-day) and kept in different conditions (under the light and in the dark). The antibacterial activities of these ZnO nanofluids were evaluated by estimating the reduction ratio of the bacteria treated with ZnO. The results showed that the ZnO nanofluid stored for 120 days under the light had the best antibacterial behavior against escherichia coli DH5a. SeM images suggest that an interaction between the ZnO particles and the e. coli bacteria cells caused by electrostatic forces might be a mechanism.

关键词： Antibacterial Nanofluids ZnO e. coli Photocatalysis

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INVeRSION OF THe BReMMeR SeRIeS

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Journal of Computational Mathematics 2017年第5期35卷 586-599页

作者： Hala A.H. Shehadeh Alison e. malcolm John C. Schotland Department of Mathematics and Statistics James Madison University Harrisonburg VA 22801 earth Sciences Department Memorial University of Newfoundland St John's Canada Department of Mathematics and Department of Physics University of Michigan Ann Arbor MI 48109 USA

We consider the inverse backscattering problem for scalar waves in one dimension. We analyze the convergence of the inverse Bremmer series in this context and study its use in numerical simulations.

关键词： Inverse scattering.

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The innate immune system in Parkinson's disease:a novel target promoting endogenous neuroregeneration

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Neural Regeneration Research 2015年第5期10卷 704-706页

作者： Johannes CM Schlachetzki Jürgen winkler Department of Molecular Neurology Friedrich-AlexanderUniversity (FAU) erlangen-Nürnberg University Hospital Erlangen

Parkinson＇s disease （PD） is a slowly progressing neuro- degenerative disorder clinically defined by key symptoms like bradykinesia, rigidity, resting tremor, and postural instability. Reduction of dopaminergic terminals in the caudate nucleus and putamen, i.e., the striatum, accom- panied by decreased striatal levels of dopamine, and most likely consecutive degeneration of dopaminergic neurons in the substantia nigra pars compacta （SNpc） are tightly linked to the onset of the motor symptoms. With the etiology of PD largely not yet well defined, there is accu- mulating evidence for increased immune activation in PD. The majority of studies favor a detrimental effect of microglia, the resident innate immune cells of the brain, on PD pathogenesis. In the presence of alpha-synuclein, inflammatory responses elicited by microglia may be initiated by pattern recognition receptors, e.g.,

关键词： SVZ GFAP PD

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