检索结果-南通市图书馆

Orchestration between ILC2s and Th2 cells in shaping type 2 immune responses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cellular & Molecular Immunology 2019年第3期16卷 225-235页

作者： rama krishna Gurram Jinfang Zhu Molecular and Cellular Immunoregulation Section Laboratory of Immune System BiologyNational Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMD 20892USA

The type 2 immune response is critical for host defense against large parasites such as *** the other hand,dysregulation of the type 2 immune response may cause immunopathological conditions,including asthma,atopic dermatitis,rhinitis,and ***,a balanced type 2 immune response must be achieved to mount effective protection against invading pathogens while avoiding *** classical model of type 2 immunity mainly involves the differentiation of type 2 T helper(Th2)cells and the production of distinct type 2 cytokines,including interleukin-4(IL-4),IL-5,and *** 2 innate lymphoid cells(ILC2s)were recently recognized as another important source of type 2 *** eosinophils,mast cells,and basophils can also express type 2 cytokines and participate in type 2 immune responses to various degrees,the production of type 2 cytokines by the lymphoid lineages,Th2 cells,and ILC2s in particular is the central event during the type 2 immune *** this review,we discuss recent advances in our understanding of how ILC2s and Th2 cells orchestrate type 2 immune responses through direct and indirect interactions.

关键词： Type 2 immune response type 2 T helper cell(Th2) Group 2 innate lymphoid cell(ILC2) Allergy and asthma

Tribological Properties of A356.2/RHA Composites

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2012年第4期28卷 367-372页

作者： D. Siva Prasad A. rama krishna Department of Mechanical Engineering GITAM University Visakhapatnam Andhra Pradesh India Department of Mechanical Engineering ANDHRA University Visakhapatnam Andhra Pradesh India

Rice husk ash （RHA） is one of the industrial waste byproduct available abundantly in the world. In the present work, an attempt is made to incorporate the RHA particles in the molten aluminum A356,2 alloy. The RHA particles were added into the matrix melt by creating a vortex with the help of a mechanical stirrer and the melt temperature was maintained between 800 and 850 ℃. Dry sliding wear experiments were performed in a pin on disc wear equipment against a chromium steel disc at 30 ℃. Scanning electron microscopy is used to study the wear characteristics of the unreinforced AI alloy and the A356.2/RHA composites. From the experiments it is observed that the composites exhibit higher hardness and resistance to wear as compared to unreinforced AI alloy,

关键词： Rice husk ash A356.2 Aluminum alloy Wear

Modeling and multi-response optimization of machining performance while turning hardened steel with self-propelled rotary tool

在线全文

学校读者我要写书评

暂无评论

Advances in Manufacturing 2015年第1期3卷 84-95页

作者： Thella Babu Rao A.Gopala krishna Ramesh Kumar Katta Konjeti rama krishna Department of Mechanical Engineering GITAM UniversityHyderabad 502329Andhra PradeshIndia Department of Mechanical Engineering University College of EngineeringJNTUKKakinada 533003Andhra PradeshIndia Productionisation & Technology Transfer Defence R&D LaboratoryKanchanbaghHyderabad 500058Andhra PradeshIndia

There are many advanced tooling approaches in metal cutting to enhance the cutting tool performance for machining hard-to-cut materials. The self propelled rotary tool （SPRT） is one of the novel approaches to improve the cutting tool performance by providing cutting edge in the form of a disk, which rotates about its principal axis and provides a rest period for the cutting edge to cool and allow engaging a fresh cutting edge with the work piece. This paper aimed to present the cutting performance of SPRT while turning hardened EN24 steel and optimize the machining conditions. Surface roughness （Ra） and metal removal rate （rMMR） are considered as machining perfor- mance parameters to evaluate, while the horizontal incli- nation angle of the SPRT, depth of cut, feed rate and spindle speed are considered as process variables. Initially, design of experiments （DOEs） is employed to minimize the number of experiments. For each set of chosen process variables, the machining experiments are conducted on computer numerical control （CNC） lathe to measure the machining responses. Then, the response surface method- ology （RSM） is used to establish quantitative relationships for the output responses in terms of the input variables. Analysis of variance （ANOVA） is used to check the adequacy of the model. The influence of input variables on the output responses is also determined. Consequently, these models are formulated as a multi-response optimi- zation problem to minimize the Ra and maximize the rMMR simultaneously. Non-dominated sorting genetic algorithm-II （NSGA-II） is used to derive the set of Pareto-optimal solutions. The optimal results obtained through the pro- posed methodology are also compared with the results of validation experimental runs and good correlation is found between them.

关键词： Self-propelled rotary turning ~ Empiricalmodeling ~ Response surface methodology (RSM) - Multi-objective formulation - Optimization - Non-dominatedsorting genetic algorithm-II (NSGA-II)

Improving Performance of a Distributed File System Using a Speculative Semantics-Based Algorithm

在线全文

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2015年第6期20卷 583-593页

作者： Talluri Lakshmi Siva rama krishna Thirumalaisamy Ragunathan Sudheer Kumar Battula K L University Andhra PradeshIndia and Research ScholarJawaharlal Nehru Institute of Advanced Studies (JNIAS) ACE Engineering College

File-sharing semantics is used by the file systems for sharing data among concurrent client processes in a consistent manner. Session semantics is a widely used file-sharing semantics in Distributed File Systems(DFSs). The main disadvantage of session semantics is that writes to an open file are visible to the concurrent client processes only during their next session. Recently, "linearizability semantics" was introduced in Blob Seer DFS, in which a Read Client Process(RCP) can read only a previous version of a binary large object(blob), while update operations are carried out on that blob in a concurrent manner. In this paper, we propose a new type of file-sharing semantics, namely "speculative semantics", which permits writes to an open file to be visible to other concurrent processes provided that data consistency is not affected. In addition, we propose a new read algorithm for DFSs based on speculative semantics and a new performance measurement metric called Currency. The experimental results obtained using Blob Seer DFS indicate that the proposed read algorithm performs better than the existing read algorithm of Blob Seer DFS.

关键词： distributed system Hadoop Blobseer concurrency spe

Fabrication of ceramic coatings on the biodegradable ZM21 magnesium alloy by PEO coupled EPD followed by laser texturing process

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2021年第3期9卷 910-926页

作者： Hariprasad Sampatirao Saikiran Amruthaluru Premchand Chennampalli rama krishna Lingamaneni Rameshbabu Nagumothu Department of Metallurgical and Materials Engineering National Institute of TechnologyTiruchirappalli 620015India Centre for Engineered Coatings International Advanced Research Centre for Powder Metallurgy and New Materials(ARCI)Hyderabad 500005India

Zirconia(ZrO_2)incorporated ceramic coatings were fabricated on biodegradable ZM21 Mg alloy by the PEO coupled with EPD ***,the sample surface was modified by laser texturing to improve the corrosion resistance,roughness and cell proliferation and growth *** corrosion performance of the fabricated samples along with the substrate was studied by electrochemical measurements under simulated body fluid(SBF)*** cell direct contact assay was conducted for the substrate and fabricated samples using L-929 mouse fibroblast cells for 24 *** phase contrast images of cell direct contact assay revealed that fabricated samples exhibited better contact and response with the fibroblast cells,compared to the *** addition of nanoparticles in the PEO process,called PEO coupled EPD process,resulted in attaining a higher thickness and improved corrosion performance of the samples than the PEO coated *** all the samples,laser surface textured PEO,and PEO-EPD coated samples unveiled enhanced corrosion resistance,cell growth,thereby enabling it as a suitable prototype for biodegradable implant applications.

关键词： ZM21 ZrO_(2)nanoparticle PEO-EPD Laser texturing Corrosion resistance L-929 cells

Review Article on Condition Assessment of Structures Using Electro-Mechanical Impedance Technique

在线全文

学校读者我要写书评

暂无评论

Structural Durability & Health Monitoring 2022年第2期16卷 97-128页

作者： krishna Kumar Maurya Anupam Rawat rama Shanker Department of Civil Engineering MNNIT AllahabadPrayagraj211004India

Structural health monitoring(SHM)is a process for determination of presence,location,severity of damages and remaining life of the *** is widely applied in aerospace,mechanical and civil engineering sys-tems to assess the conditions of structures to improve the operation,safety,serviceability and reliability,*** are various SHM techniques for monitoring the health of structures such as global response based and local *** occur in the structures due to its inability to withstand intended design loadings,physical environment and chemical ***,damage identification is necessary to improve the durability of the structures for protection against catastrophic *** research paper is focused on elec-tro-mechanical impedance(EMI)technique which is one of the techniques based on smart *** smart materials are utilized for monitoring the health of the *** are used for damage determination and its quantification for the interrogated *** in admittance or impedance signature shows the existence of damage in the ***,the different statistical methods viz.,root mean square deviation(RMSD),mean absolute percentage deviation(MAPD),covariance(Cov),and correlation coefficient(CC)are used for the quantification of *** material such as piezoelectric materials,its properties and applica-tions are also *** this paper,the implementation of EMI technique based on different recent advances in smart materials and their appropriateness have been ***,the reviewed investigations are significant for the monitoring of real-life *** presented paper is the compact state-of-the-art for EMI technique which is used for *** examination will be valuable to infrastructural health monitoring and engineering applications in respect to innovative research directions.

关键词： Structural health monitoring condition assessment EMI technique PZT patches damages

Electrospun CNT embedded ZnO nanofiber based biosensor for electrochemical detection of Atrazine: a step closure to single molecule detection

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Microsystems & Nanoengineering 2020年第1期6卷 1353-1362页

作者： Patta Supraja Vikrant Singh Siva rama krishna Vanjari Shiv Govind Singh Department of Electrical Engineering Indian Institute of TechnologyHyderabadTelangana 502285India School of Medicine University of California DavisDavisCaliforniaUSA

In this study we have reported the design and development of a facile,sensitive,selective,and label-free electrochemical sensing platform for the detection of atrazine based on MWCNT-embedded ZnO *** nanofibers were characterized using scanning electron microscope(SEM),transmission electron microscope(TEM),X-ray diffraction(XRD),X-ray photoelectron spectroscope(XPS),UV-Visible spectroscope(UV-VIS),and Fourier-transform infrared spectroscope(FTIR).Electrochemical properties of MWCNT-ZnO nanofiber-modified electrodes were assessed using electrochemical impedance spectroscopy(EIS)and cyclic voltammetry(CV).Binding event of atrazine to anti-atrazine antibody,which immobilized on nanofiber-modified electrode via EDC and NHS chemistry,was transduced with *** to high conductivity,surface area,and low bandgap of MWCNT-ZnO nanofibers,we have achieved the sensitivity and limit of detection(LoD)of sensor as 21.61(KΩμg^(−1) mL^(−1))cm^(−2) and 5.368zM for a wide detection range of 10 zM–1µ*** proposed immunosensing platform has good stability,selectivity,repeatability,and reproducibility,and are less prone to interference.

关键词： fiber fibers closure

Fabrication and Characterisation of Rutile-TiO_2 Coatings on Metallic Alloy Substrates

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

材料热处理学报 2004年第05B期25卷 862-865页

作者： D. Siva rama krishna School of Materials Engineering Nanyang Technological University Singapore 639798

In the present work, attempts have been made to extend the use of the tribological and chemical properties of rutile-TiO2 to metallic alloy systems, by forming a rutile coating on the metallic substrates. Two metallic alloys were selected in this study, including AISI316L austenitic stainless steel and aluminium alloy. The rutile-based coatings were fabricated by magnetron sputter deposition of a pure titanium coating first, and then thermal oxidation of the coated specimens to partially convert the titanium coating to rutile oxide and to promote interfacial reactions which can significantly enhance the coating-substrate adhesion strength. The structures and properties of the coating-substrate systems were characterized by a variety of analytical and experimental techniques, including X-ray diffraction, glow discharge spectrometry, high resolution SEM, nanoindentation, microscratch, friction and wear testing, as well as electrochemical testing. The results show that the friction and wear properties, as well as the corrosion resistance of the metallic alloys can be significant enhanced by surface engineering with rutile-TiO2.

关键词：金红石二氧化钛不锈钢磨损性能耐蚀性

Additive manufacturing of biodegradable magnesium-based materials:Design strategies,properties,and biomedical applications

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2023年第3期11卷 801-839页

作者： Farzad Badkoobeh Hossein Mostaan Mahdi Rafiei Hamid Reza Bakhsheshi-Rad Seeram rama krishna Xiongbiao Chen School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehranIran Faculty of Engineering Department of Materials and Metallurgical EngineeringArak UniversityArakIran Advanced Materials Research Center Department of Materials EngineeringNajafabad BranchIslamic Azad UniversityNajafabadIran Department of Mechanical Engineering National University of Singapore9 Engineering Drive 1Singapore 117576Singapore Department of Mechanical Engineering College of EngineeringUniversity of SaskatchewanSaskatoonSK S7N 5A9Canada

Magnesium(Mg)-based materials are a new generation of alloys with the exclusive ability to be biodegradable within the human/animal *** addition to biodegradability,their inherent biocompatibility and similar-to-bone density make Mg-based alloys good candidates for fabricating surgical bioimplants for use in orthopedic and traumatology *** this end,nowadays additive manufacturing(AM)along with three-dimensional(3D)printing represents a promising manufacturing technique as it allows for the integration of bioimplant design and manufacturing processes specific to given ***,this technique also faces many new challenges associated with the properties of Mg-based alloys,including high chemical reactivity,potential for combustion,and low vaporization *** this review article,various AM processes to fabricate biomedical implants from Mg-based alloys,along with their metallic microstructure,mechanical properties,biodegradability,biocompatibility,and antibacterial properties,as well as various post-AM treatments were critically ***,the challenges and issues involved in AM processes from the perspectives of bioimplant design,properties,and applications were identified;the possibilities and potential scope of the Mg-based scaffolds/implants are discussed and highlighted.

关键词： Magnesium alloy Additive manufacturing 3D Printing Bone tissue engineering Scaffold Mechanical and biological properties