检索结果-南通市图书馆

Mesenchymal stem cell therapy in retinal and optic nerve diseases: An update of clinical trials

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Stem Cells 2016年第11期8卷 376-383页

作者： Sonia Labrador-Velandia María Luz Alonso-Alonso Sara Alvarez-Sanchez Jorge González-Zamora Irene Carretero-Barrio José Carlos Pastor Iván Fernandez-Bueno girish kumar srivastava Instituto Universitario de Oftalmobiología Aplicada Universidad de Valladolid 47011 Valladolid Spain Facultad de Medicina Universidad de Valladolid 47005 Valladolid Spain Centro en Red de Medicina Regenerativa y Terapia Celular de Castilla y León 47011 Valladolid Spain Red Temática de Investigación Cooperativa Sanitaria del Instituto de Salud Carlos Ⅲ. Oftared 28029 Madrid Spain Hospital Clínico Universitario de Valladolid 47003 Valladolid Spain

Retinal and optic nerve diseases are degenerative ocular pathologies which lead to irreversible visual loss. Since the advanced therapies availability, cell-based therapies offer a new all-encompassing approach. Advances in the knowledge of neuroprotection, immunomodulation and regenerative properties of mesenchymal stem cells(MSCs) have been obtained by several preclinical studies of various neurodegenerative diseases. It has provided the opportunity to perform the translation of this knowledge to prospective treatment approaches for clinical practice. Since 2008, several first steps projecting new treatment approaches, have been taken regarding the use of cell therapy in patients with neurodegenerative pathologies of optic nerve and retina. Most of the clinical trials using MSCs are in Ⅰ/Ⅱ phase, recruiting patients or ongoing, and they have as main objective the safety assessment of MSCs using various routes of administration. However, it is important to recognize that, there is still a long way to go to reach clinical trials phase Ⅲ-Ⅳ. Hence, it is necessary to continue preclinical and clinical studies to improve this new therapeutic tool. This paper reviews the latest progress of MSCs in human clinical trials for retinal and optic nerve diseases.

关键词： Mesenchymal stem cells Cell therapy Optic nerve diseases Clinical trials Retinal diseases

Fluid Inclusion Characteristics of Tungsten Mineralization in the Agargaon Area of Sakoli Fold Belt, Central India

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 Earth Science 2020年第3期31卷 559-570页

作者： girish kumar Mayachar Subhasish Ghosh National Centre for Excellence in Geoscience Research Remote Sensing and Aerial SurveyGeological Survey of IndiaBangalore 560078India

The Lower to Middle Proterozoic Sakoli fold belt in Central India forms a triangular belt with significant mineralization of strategic *** Sakoli fold belt comprises metasediments,felsic and mafic volcanics with metabasalts bounded by the gneissic-migmatitic *** last pulses of granitic activity in the form of quartz lenses intrude the metasediments and are associated with tungsten *** metasediments are intruded by the quartz veins and tourmaline breccias trending 60°N to 65°E and 60°S to 65°W and are parallel to the regional structural *** tungsten mineralization in this area is restricted to tourmaline-quartz mica greisens and quartz *** NE-SW trending foliated contact zones of chlorite mica schist and porphyritic granite/gneisses have served as easy channels for the mineralizing vapours and solutions to percolate,which formed ore bearing greisens and quartz *** mineralization is erratic and manifested by sparse and sporadic disseminations of wolframite and scheelite associated with minor amount of molybdenite and *** fluid inclusion microthermometry on mineralized quartz veins and quartz-tourmaline veins reveals the existence of a metamorphogenic aqueous-gaseous(H2O-CO2+NaCl)fluid that underwent phase separation and gave rise to gaseous(CO2)*** salinity of tungsten mineralizations varies from low to high(1.32 wt.%to 40.44 wt.%NaCl eq.).The estimated P-T range of tungsten mineralization varies from 1.2 to 2.2 kbar at 280 to 390℃.Raman spectroscopy reveals that the fluid inclusions mainly contain H2O and CO2 with rarely H2S and *** isotopic data reveal that the sulfur isotope fractions from the depositsδ^34S ranging from+3.1‰to+3.35‰,suggesting the deep crustal source for the sulfur,which can be further interpreted as a single(magmatic)supply of sulfur during magmatic-hydrothermal *** studies reveal the presence of chlorides such as FeCl2/MgCl2 and CaCl2,indicating t

关键词： Sakoli fold belt fluid inclusions tungsten

Numerical Algorithm Based on Quintic Nonpolynomial Spline for Solving Third-Order Boundary Value Problems Associated with Draining and Coating Flows

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2012年第6期33卷 831-840页

作者： Pankaj kumar srivastava Manoj kumar Department of Mathematics Jaypee Institute of Information Technology Department of Mathematics Motilal Nehru National Institute of Technology

A numerical algorithm is developed for the approximation of the solution to certain boundary value problems involving the third-order ordinary differential equation associated with draining and coating flows. The authors show that the approximate so- lutions obtained by the numerical algorithm developed by using uonpolynomial quintic spline functions ave better than those produced by other spline and domain decomposition methods. The algorithm is tested on two problems associated with draining and coating flows to demonstrate the practical usefulness of the approach.

关键词： Third-order boundary value problem Spline functions Nonpolynomial quartic spline Nonpolynomial quintic spline Draining and coating flows

A Context Sensitive Multilevel Thresholding Using Swarm Based Algorithms

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2019年第6期6卷 1471-1486页

作者： Shreya Pare Anil kumar Varun Bajaj girish kumar Singh PDPM Indian Institute of Information Technology Design and Manufacturing Jabalpur 482005MPIndia Institute of Technology Roorkee Uttarakhand 247667India

In this paper, a comprehensive energy function is used to formulate the three most popular objective functions:Kapur's, Otsu and Tsalli's functions for performing effective multilevel color image thresholding. These new energy based objective criterions are further combined with the proficient search capability of swarm based algorithms to improve the efficiency and robustness. The proposed multilevel thresholding approach accurately determines the optimal threshold values by using generated energy curve, and acutely distinguishes different objects within the multi-channel complex images. The performance evaluation indices and experiments on different test images illustrate that Kapur's entropy aided with differential evolution and bacterial foraging optimization algorithm generates the most accurate and visually pleasing segmented images.

关键词： Color image segmentation Kapur's entropy multilevel thresholding Otsu method swarm based optimization algorithms Tsalli's entropy

Recent advances in catalytic combustion of AP-based composite solid propellants

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2021年第3期17卷 1013-1031页

作者： Narendra Yadav Prem kumar srivastava Mohan Varma Department of Space Engineering&Rocketry India Department of Chemistry Birla Institute of TechnologyMesraRanchiIndia

Composite solid propellants(CSPs) have widely been used as main energy source for propelling the rockets in both space and military applications. Internal ballistic parameters of rockets like characteristic exhaust velocity, specific impulse, thrust, burning rate etc., are measured to assess and control the performance of rocket motors. The burn rate of solid propellants has been considered as most vital parameter for design of solid rocket motors to meet specific mission requirements. The burning rate of solid propellants can be tailored by using different constituents, extent of oxidizer loading and its particle size and more commonly by incorporating suitable combustion catalysts. Various metal oxides(MOs),complexes, metal powders and metal alloys have shown positive catalytic behaviour during the combustion of CSPs. These are usually solid-state catalysts that play multiple roles in combustion of CSPs such as reduction in activation energy, enhancement of rate of reaction, modification of sequences in reaction-phase, influence on condensed-phase combustion and participation in combustion process in gas-phase reactions. The application of nanoscale catalysts in CSPs has increased considerably in recent past due to their superior catalytic properties as compared to their bulk-sized counterparts. A large surface-to-volume ratio and quantum size effect of nanocatalysts are considered to be plausible reasons for improving the combustion characteristics of propellants. Several efforts have been made to produce nanoscale combustion catalysts for advanced propellant formulations to improve their energetics. The work done so far is largely scattered. In this review, an effort has been made to introduce various combustion catalysts having at least a metallic entity. Recent developments of nanoscale combustion catalysts with their specific merits are discussed. The combustion chemistry of a typical CSP is briefly discussed for providing a better understanding on role of co

关键词： Composite solid propellants Burn rate modifier Metallic nano-catalysts Catalytic combustion Thermal decomposition

Advancement in biogas production from the solid waste by optimizing the anaerobic digestion

在线全文

学校读者我要写书评

暂无评论

Waste Disposal and Sustainable Energy 2020年第2期2卷 85-103页

作者： Sunil kumar srivastava Department of Environmental Science/Chemistry Jaypee University of Engineering and TechnologyRaghogarhGunaMP 473226India

The crisis of fossil fuel and their negative impact on the environment has caused concern among the scientific communities leading them to look around for renewable sources of *** review has emphasized the efficient utilization of organic municipal solid waste as well as agriculture waste in an anaerobic digester for the production of biogas as a sustainable renewable *** advances in biogas production along with previous research work have been discussed to offer a comprehensive synopsis of the accumulated *** review also elucidates about the design of an anaerobic digester,the prospect of anaerobic digestion and opportunity in new advances in *** is one of the most accepted sustainable renewable *** characterization,elimination of contaminants,pretreatment,anaerobic diges-tion in optimum condition and utilization of energy crops enhanced the efficiency of an anaerobic *** of segregated organic solid waste increased its putrescibility and further biogas *** optimized parameters in this review were pH,temperature,loading rate,C/N ratio and solid/liquid ratio of the *** flow rate of the feedstock was optimized according to the available volume of the digester,residence time and the characteristics of the *** design of an anaerobic digester should be preferably cylindrical in shape,with a diameter ranging from 6 to 40 m,the depth ranging from 7.5 to 15 m and the conical floor having a slope around 15%.A comprehensive reform in technical,economic,and social policies is essential to accomplish a sustainable energy system considering biogas as a future renewable *** flowsheet of the biogas and methanol production has been given in Fig.1.

关键词： Renewable energy Anaerobic digestion Biomass Biogas Energy crops Solid waste

Varna-based optimization:a novel method for capacitated controller placement problem in SDN

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2020年第3期14卷 87-111页

作者： Ashutosh kumar SINGH Saurabh MAURYA Shashank srivastava Department of Computer Science&Engineering Motilal Nehru National Institute of Technology AllahabadAllahabad 211004U.P.India

Recently,software defined networking(SDN)is a promising paradigm shift that decouples the control plane from the data *** can centrally monitor and control the network through softwarization,i.e.,*** controllers are a necessity of current SDN based *** multiple controllers in an optimum way is known as controller placement problem(CPP).Earlier,solutions of CPP only concentrated on propagation latency but overlooked the capacity of controllers and the dynamic load on switches,which is a significant factor in real *** this paper,we develop a novel optimization algorithm named varna-based optimization(VBO)and use it to solve *** the best of our knowledge,this is the first attempt to minimize the total average latency of SDN along with the implementation of TLBO and Jaya algorithms to solve CPP for all twelve possible *** experimental results show that TLBO outperforms PSO,and VBO outperforms TLBO and Jaya algorithms in all scenarios for all topologies.

关键词： SDN controller placement CPP latency VBO

Security Attacks in Named Data Networking: A Review and Research Directions

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 Computer Science & Technology 2019年第6期34卷 1319-1350页

作者： Naveen kumar Ashutosh kumar Singh Abdul Aleem Shashank srivastava Department of Computer Science and Engineering Motilal Nehru National Institute of Technology Allahabad Prayagraj 211004India

Contents such as audios,videos,and images,contribute most of the Internet traffic in the current *** content sharing is a tedious *** existing security solutions do not secure data but secure the communicating *** data networking(NDN)secures the data by enforcing the data publisher to sign the *** user can verify the data by using the public key of the *** is resilient to most of the probable security attacks in the TCP/IP model due to its new ***,new types of attacks are possible in *** article surveys the most significant security attacks in NDN such as interest flooding attacks,cache privacy attacks,cache pollution attacks,and content poisoning *** attack is classified according to their behavior and discussed for their detection techniques,countermeasures,and the affected *** article is an attempt to help new researchers in this area to gather the domain knowledge of *** article also provides open research issues that could be addressed by researchers.

关键词： named data networking(NDN) interest flooding attack cache privacy attack cache pollution attack content poisoning attack

Zinc Oxide Nanostructures for NO_2 Gas–Sensor Applications:A Review

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano-Micro Letters 2015年第2期7卷 97-120页

作者： Rajesh kumar O.Al-Dossary girish kumar Ahmad Umar PG Department of Chemistry JCDAV College Department of Physics King Saud University Department of Chemistry Faculty of Arts and Sciences Najran University Promising Centre for Sensors and Electronic Devices (PCSED) Najran University

Because of the interesting and multifunctional properties,recently,ZnO nanostructures are considered as excellent material for fabrication of highly sensitive and selective gas ***,ZnO nanomaterials are widely used to fabricate efficient gas sensors for the detection of various hazardous and toxic *** presented review article is focusing on the recent developments of NO2gas sensors based on ZnO *** review presents the general introduction of some metal oxide nanomaterials for gas sensing application and finally focusing on the structure of ZnO and its gas sensing *** gas sensing characteristics such as gas response,response time,recovery time,selectivity,detection limit,stability and recyclability,etc are also discussed in this ***,the utilization of various ZnO nanomaterials such as nanorods,nanowires,nano-micro flowers,quantum dots,thin films and nanosheets,etc for the fabrication of NO2gas sensors are also ***,various factors such as NO2concentrations,annealing temperature,ZnO morphologies and particle sizes,relative humidity,operating temperatures which are affecting the NO2gas sensing properties are discussed in this ***,the review article is concluded and future directions are presented.

关键词： ZnO nanostructure Gas sensors Sensor parameters Sensor mechanism