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Hydrogen cyanide production by soil bacteria: Biological control of pests and promotion of plant growth in sustainable agriculture

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Pedosphere 2022年第1期32卷 15-38页

作者： Anju SEHrAWAt Satyavir S.SInDHU Bernard r.GLICK Department of Microbiology CCS Haryana Agricultural UniversityHisar 125004India 2Department of BiologyUniversity of WaterlooWaterloo ON N2L 3G1Canada

Currently, plant diseases and insect infestations are mainly controlled by the extraneous application of pesticides. Unfortunately, the indiscriminate use of such agrochemicals can cause ecological and environmental problems, as well as human health hazards. to obviate the potential pollution arising from the application of agrochemicals, biological control of soilborne pathogens or insect pests using antagonistic microorganisms may be employed. Certain soil bacteria, algae, fungi, plants and insects possess the unique ability to produce hydrogen cyanide(HCn), which plays an important role in the biotic interactions of those organisms. In particular, cyanogenic bacteria have been found to inhibit the growth of various pathogenic fungi, weeds, insects, termites and nematodes. thus, the use of HCn-producing bacteria as biopesticides offers an ecofriendly approach for sustainable agriculture. the enzyme, HCn synthase,involved in the synthesis of HCn, is encoded by the hcnABC gene cluster. the biosynthetic regulation of HCn, antibiotics and fluorescent insecticidal toxins through the conserved global regulatory GacS/GacA system is elaborated in this review, including approaches that may optimize cyanogenesis for enhanced pest control. In addition, the effects of bacterially synthesized HCn on the production of indole acetic acid, antibiotics and fluorescent insecticidal toxins, 1-aminocyclopropane-1-carboxylate deaminase utilization and phosphate solubilization may result in the stimulation of plant growth. A more detailed understanding of HCn biosynthesis and regulation may help to elaborate the precise role of this compound in biotic interactions and sustainable agriculture.

关键词： biocontrol agent biopesticide cyanogenesis fluorescent insecticidal toxin pathogen

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Mathematical modeling of the dynamics of COVID-19 variants of concern:Asymptotic and finite-time perspectives

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Infectious Disease Modelling 2022年第4期7卷 581-596页

作者： Adriana-Stefania Ciupeanu Marie Varughese Weston C.roda Donglin Han Qun Cheng Michael Y.Li Department of Mathematics and Department of Statistics University of ManitobaWinnipegManitobaR3T 2N2Canada Analytics and Performance reporting Branch Alberta HealthEdmontonAlbertaCanada Department of Mathematical and Statistical Sciences University of AlbertaEdmontonAlbertaT6G 2G1Canada

the COVID-19 pandemic has seen multiple waves,in part due to the implementation and relaxation of social distancing measures by the public health authorities around the world,and also caused by the emergence of new variants of concern(VOCs)of the SArS-Cov-2 *** the COVID-19 pandemic is expected to transition into an endemic state,how to manage outbreaks caused by newly emerging VOCs has become one of the primary public health *** mathematical modeling tools,we investigated the dynamics of VOCs,both in a general theoretical framework and based on observations from public health data of past COVID-19 waves,with the objective of understanding key factors that determine the dominance and coexistence of *** results show that the transmissibility advantage of a new VOC is a main factor for it to become ***,our modeling study indicates that the initial number of people infected with the new VOC plays an important role in determining the size of the *** results also support the evidence that public health measures targeting the newly emerging VOC taken in the early phase of its spread can limit the size of the epidemic caused by the new VOC(Wu et al.,2139Wu,Scarabel,Majeed,Bragazzi,&Orbinski,Wu et al.,2021).

关键词： COVID-19 pandemic Variants of concern Mathematical modeling Coexistence and replacement of variants Public health measures

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地磁感应电流(GIC)的作用与评估

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地球物理学报 2005年第6期48卷 1282-1287页

作者：马晓冰 Ian J.Ferguson 孔祥儒 Xianghong Wu 闫永利中国科学院地质与地球物理研究所北京100029University of ManitobaCanada R3T 2 N2 University of Manitoba Canada R3T 2 N2 中国科学院地质与地球物理研究所北京100029

地磁感应电流(GIC)可能对各种人工长距离导电体造成影响与危害.地磁扰动产生的感应电场的强度与地磁场强度、地下电阻率结构相关,在导电系统内生成的GIC的强度则同时与导电系统的内在结构有关.计算了加拿大Manitoba省三个典型地区在2000... 详细信息

地磁感应电流(GIC)可能对各种人工长距离导电体造成影响与危害.地磁扰动产生的感应电场的强度与地磁场强度、地下电阻率结构相关,在导电系统内生成的GIC的强度则同时与导电系统的内在结构有关.计算了加拿大Manitoba省三个典型地区在2000年7月15日的一个强烈磁暴期间产生的感应电场.通过对地磁活动性的统计分析,估计加拿大魁北克电网可能经受的最大GIC达每相78A(一年一次)和234A(每十年一次).

关键词：地磁感应电流地磁扰动感应电场

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roughness Effects on Continuous and Discrete Flows in Superhydrophobic Microchannels

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Communications in Computational Physics 2011年第5期9卷 1094-1105页

作者： Junfeng Zhang Daniel Y.Kwok School of Engineering Laurentian UniversitySudburyOntarioP3E 2C6Canada nanoscale technology and Engineering Laboratory Department of Mechanical EngineeringSchulich School of EngineeringUniversity of CalgaryCalgaryAlbertaT2N 1N4Canada

the dynamic behaviors of continuous and discrete flows in superhydrophobic microchannels are investigated with a lattice Boltzmann *** characters of the superhydrophobic phenomenon are well observed from our simulations,including air trapped in the surface microstructures,high contact angles,low contact angle hysteresis,and reduced friction to fluid *** the roughness of a hydrophobic surface can produce a large flow rate through the channel due to the trapped air,implying less friction or large apparent *** apparent slip length appears to be independent to the channel width and could be considered as a surface *** a moving droplet,its behavior is affected by the surface roughness from two aspects:the contact angle difference between its two ends and the surface-liquid interfacial *** a consequence,the resulting droplet velocity changes with the surface roughness as firstly decreasing and then *** results are also compared with experimental observations and better agreement has been obtained than that from other numerical *** information from this study could be valuable for microfluidic systems.

关键词： Lattice Boltzmann method interfacial slip superhydrophobicity solid-fluid interaction roughness effect microchannels

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Identification of greigite in lake sediments and its magnetic significance

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Science China Earth Sciences 2002年第1期45卷 81-87页

作者：胡守云 E.Appel V.Hoffmann W.Schmahl 1. nanjing Institute of Geography & Limnology Chinese Academy of Sciences 210008 Nanjing China 2. Institut für Geologie und Pal?ontologie Universit?t Tübingen 72076 Tübingen Germany 3. Institut für Mineralogie Ruhr-Universtit?t Bochum 44780 Bochum Germany

Detailed rock magnetic investigations and mineralogical analysis were conducted on lacustrine sediments recovered from Zoigê Basin, eastern tibetan Plateau. Greigite, with fine and homogenous grain size, is found as a main magnetic carrier, which is suspected to be of biochemical origin. In contrast to some reports, greigite within the sediments is not oxidized even after exposure to air for a few years, which could be due to the fact that greigite is sealed by silicate.

关键词： greigite lacustrine sediments rock magnetism X-ray diffraction SEM

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Viscosity and degradation controlled injectable hydrogel for esophageal endoscopic submucosal dissection

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Bioactive Materials 2021年第11期6卷 1150-1162页

作者： Chaoqiang Fan Kaige Xu Yu Huang Shuang Liu tongchuan Wang Wei Wang Weichao Hu Lu Liu Malcolm Xing Shiming Yang Department of Gastroenterology Xinqiao HospitalArmy Medical UniversityNO.183Xinqiao StreetShapingba DistrictChongqing City400037People’s Republic of China Department of Mechanical Engineering Biochemistry and Medical GeneticsUniversity of ManitobaWinnipeg MBR3T 2N2ManitobaCanada

Endoscopic submucosal dissection(ESD)is a common procedure to treat early and precancerous gastrointestinal *** submucosal injection,a liquid cushion is created to lift and separate the lesion and malignant part from the muscular layer where the formed indispensable space is convenient for endoscopic *** is a most common submucosal injection liquid,but the formed liquid pad lasts only a short time,and thus repeated injections increase the potential risk of adverse *** with high osmotic pressure and high viscosity are used as an alternate;however,with some drawbacks such as tissue damage,excessive injection resistance,and high ***,we reported a nature derived hydrogel of gelatin-oxidized alginate(G-OALG).Based on the rheological analysis and compare to commercial endoscopic mucosal resection(EMr)solution(0.25%hyaluronic acid,HA),a designed G-OALG hydrogel of desired concentration and composition showed higher performances in controllable gelation and injectability,higher viscosity and more stable *** G-OALG gel also showed lower propulsion resistance than 0.25%HA in the injection force assessment under standard endoscopic instruments,which eased the surgical *** addition,the G-OALG hydrogel showed good in vivo degradability *** comparing the results acquired via ESD to normal saline,the G-OALG shows great histocompatibility and excellent endoscopic injectability,and enables create a longer-lasting submucosal *** the features have been confirmed in the living both pig and rat *** G-OALG could be a promising submucosal injection agent for esophageal ESD.

关键词： Injectable hydrogel Controllable gelation and viscosity Esophageal submucosal liquid cushion Early esophageal cancer Pig model

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3D free-assembly modular microfluidics inspired by movable type printing

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Microsystems & nanoengineering 2023年第5期9卷 191-201页

作者： Shaoqi Huang Jiandong Wu Lulu Zheng Yan Long Junyi Chen Jianlang Li Bo Dai Francis Lin Songlin Zhuang Dawei Zhang Engineering research Center of Optical Instrument and System the Ministry of EducationShanghai Key Laboratory of Modern Optical SystemUniversity of Shanghai for Science and TechnologyShanghai 200093China Institute of Biomedical and Health Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Department of Physics and Astronomy University of ManitobaWinnipegMB R3T 2N2Canada

reconfigurable modular microfluidics presents an opportunity for flexibly constructing prototypes of advanced microfluidic ***,the strategy of directly integrating modules cannot easily fulfill the requirements of common applications,e.g.,the incorporation of materials with biochemical compatibility and optical transparency and the execution of small batch production of disposable chips for laboratory trials and initial ***,we propose a manufacturing scheme inspired by the movable type printing technique to realize 3D free-assembly modular ***-layer 3D microfluidic structures can be produced by replicating the assembled molds.A library of modularized molds is presented for flow control,droplet generation and manipulation and cell trapping and *** addition,a variety of modularized attachments,including valves,light sources and microscopic cameras,have been developed with the capability to be mounted onto chips on *** systems,including those for concentration gradient generation,droplet-based microfluidics,cell trapping and drug screening,are *** scheme enables rapid prototyping of microfluidic systems and construction of on-chip research platforms,with the intent of achieving high efficiency of proof-of-concept tests and small batch manufacturing.

关键词： batch proof mounted

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平面两圆弧相离情况下G^2连续过渡曲线构造

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计算机辅助设计与图形学学报 2006年第2期18卷 265-269页

作者：李重马利庄 Dereck Meek 浙江理工大学数学科学系杭州310033 上海交通大学计算机科学与工程系上海200030 Department of Computer Science University of ManitobaWinnipeg R3T2N2

使用待定系数方法,找到一对合适的三次B啨zier spiral线来构造平面两相离圆弧间G^2连续过渡曲线·该方法能通过二次方程求根公式得到解析解,克服了传统方法需使用数值方法的缺陷,使得计算简化和方便;且两圆弧半径大小比例不受限制,应用... 详细信息

使用待定系数方法,找到一对合适的三次B啨zier spiral线来构造平面两相离圆弧间G^2连续过渡曲线·该方法能通过二次方程求根公式得到解析解,克服了传统方法需使用数值方法的缺陷,使得计算简化和方便;且两圆弧半径大小比例不受限制,应用范围更加广泛·最后用实例表明了该方法的有效性·

关键词： G^2连续过渡曲线回旋线三次Bézier曲线

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Postbiotics from Saccharomyces cerevisiae fermentation stabilize microbiota in rumen liquid digesta during grain-based subacute ruminal acidosis(SArA) in lactating dairy cows

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Journal of Animal Science and Biotechnology 2024年第5期15卷 2059-2080页

作者： Junfei Guo Zhengxiao Zhang Le Luo Guan Ilkyu Yoon Jan C.Plaizier Ehsan Khafipour Department of Animal Science University of ManitobaWinnipegMB R3T 2N2Canada Present Address:College of Food and Biological Engineering Jimei UniversityXiamenFujian 361021China Department of Agriculture Food and Nutrition DepartmentUniversity of AlbertaEdmontonAB T6G 2R3Canada Faculty of Land and Food Systems University of British ColumbiaVancouverBC V6T 1Z4Canada Diamond V Cedar RapidsIA 52404United States Present Address:Cargill Animal nutrition 15407 McGinty Road WestWayzataMN 55391USA

Background Subacute ruminal acidosis(SArA)is a common metabolic disorder of high yielding dairy cows,and it is associated with dysbiosis of the rumen and gut microbiome and host *** study evaluated the impact of two postbiotics from Saccharomyces cerevisiae fermentation products(SCFP)on rumen liquid associated microbiota of lactating dairy cows subjected to repeated grain-based SArA challenges.A total of 32 rumen cannulated cows were randomly assigned to 4 treatments from 4 weeks before until 12 weeks after *** groups included a Control diet or diets supplemented with postbiotics(SCFPa,14 g/d Original XPC;SCFPb-1X,19 g/d nutri tek;SCFPb-2X,38 g/d nutri tek,Diamond V,Cedar rapids,IA,USA).Grain-based SArA challenges were conducted during week 5(SArA1)and week 8(SArA2)after parturition by replacing 20%DM of the base total mixed ration(tMr)with pellets containing 50%ground barley and 50%ground *** DnA from rumen liquid samples was subjected to V3–V416S r rnA gene amplicon *** of rumen microbiota were compared among treatments and SArA *** Both SArA challenges reduced the diversity and richness of rumen liquid microbiota,altered the overall composition(β-diversity),and its predicted functionality including carbohydrates and amino acids metabolic *** SArA challenges also reduced the number of significant associations among different taxa,number of hub taxa and their composition in the microbial co-occurrence *** with SCFP postbiotics,in particular SCFPb-2X,enhanced the robustness of the rumen *** SCFP supplemented cows had less fluctuation in relative abundances of community members when exposed to SArA *** SCFP supplementation promoted the populations of lactate utilizing and fibrolytic bacteria,including members of ruminococcaceae and Lachnospiraceae,and also increased the numbers of hub taxa during non-SArA and SArA *** with S

关键词： Postbiotics rumen microbiota Saccharomyces cerevisiae fermentation products SArA

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Modeling and Identification of Multirate Systems

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自动化学报 2005年第1期31卷 105-122页

作者： FengDInG tongwenCHEn DepartmentofElectricalandComputerEngineeringUniversityofAlberta EdmontonAlbertaT6G2V4Canada

Multirate systems are abundant in industry; for example, many soft-sensor design problems are related to modeling, parameter identification, or state estimation involving multirate systems. the study of multirate systems goes back to the early 1950's, and has become an active research area in systems and control. this paper briefly surveys the history of development in the area of multirate systems, and introduces some basic concepts and latest results on multirate systems, including a polynomial transformation technique and the lifting technique as tools for handling multirate systems, lifted state space models, parameter identification of dual-rate systems, how to determine fast single-rate models from dual-rate models and directly from dual-rate data, and a hierarchical identification method for general multirate systems. Finally, some further research topics for multirate systems are given.

关键词：多速率系统识别法模型化双重速率系统参数估计系统显示分层识别

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