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A 526 mJ Subnanosecond Pulsed Hybrid-Pumped Nd：YAG Laser

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Chinese Physics Letters 2017年第7期34卷 105-108页

作者：石江鹏辛建国刘军陈家斌 sher zaman School of Optoelectronics Beijing Institute of Technology Beijing 100081 School of Automation Beijing Institute of Technology Beijing 100081 Department of Physics Karakoram International University Gilgit 15100 Pakistan

A hybrid-pumped Nd：YAG pulse laser with a double-pass two-rod configuration is presented. The focal length of offset lens is particularly studied to compensate for the thermal lens effect and depolarization. For input pulse energy of 141 μJ with pulse duration of 754ps, the pulse laser system delivers 526mJ pulse energy and 728ps pulse width output at lO Hz with pulse profile shape preservation. The energy stability of the laser pulse is less than 3%, and the beam quality factor M2 is less than 2.26.

关键词： YAG length A 526 mJ Subnanosecond Pulsed Hybrid-Pumped Nd:YAG Laser Nd

Software-Defined Space-Air-Ground Integrated Network Architecture with the Multi-Layer Satellite Backbone Network

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Computers, Materials & Continua 2020年第7期64卷 527-540页

作者： Chao Guo Cheng Gong Juan Guo Zhanzhen Wei Yanyan Han sher zaman Khan Department of Electronics and Communication Engineering Beijing Electronics Science and Technology InstituteBeijing100070China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Vocational and Technical College of Guilin University of Electronic Technology Beihai536000China Institute of Business Administration Gomal UniversityDera Ismail Khan29220Pakistan

Under the background of the rapid development of ground mobile communication,the advantages of high coverage,survivability,and flexibility of satellite communication provide air support to the construction of space information *** to the requirements of the future space information communication,a software-defined Space-Air-Ground Integrated network architecture was *** consisted of layered structure satellite backbone network,deep space communication network,the stratosphere communication network and the ground *** Space-Air-Ground Integrated network was supported by the satellite backbone *** provided data relay for the missions such as deep space exploration and controlled the deep-space spacecraft when *** addition,it safeguarded the anti-destructibility of stratospheric communication and assisted the stratosphere to supplement ground network *** this paper,algorithm requirements of the congestion control and routing of satellite backbone protocols for heterogeneous users’services were *** algorithm requirements of distinguishing different service objects for the deep space communication and stratospheric communication network protocols were *** the realistic demand for the dynamic coverage of the satellite backbone network and node cost,the multi-layer satellite backbone network architecture was *** this basis,the proposed Software-defined Space-Air-Ground Integrated network architecture could be built as a large,scalable and efficient communication network that could be integrated into space,air,and ground.

关键词： Space-Air-Ground integrated network network architecture software-defined network multi-layer satellite backbone network

Prediction of promiscuous T cell epitopes in RNA dependent RNA polymerase of Chikungunya virus

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Asian Pacific Journal of Tropical Medicine 2017年第8期10卷 825-829页

作者： Yasir Waheed sher zaman Safi Muzammil Hasan Najmi Hafsa Aziz Muhammad Imran Foundation University Medical College Foundation University IslamabadDHA-I Islamabad(44000)Pakistan Interdisciplinary Research Centre in Biomedical Materials(IRCBM) COMSATS Institute of Information TechnologyLahore CampusLahorePakistan Nuclear Medicine Oncology and Radiotherapy Institute Islamabad Islamabad(44000)Pakistan Department of Medical Laboratory Sciences(DMLS) Faculty of Health and Allied Sciences(FHAS)Imperial College of Business Studies(ICBS)LahorePakistan Department of Microbiology University of Health SciencesLahorePakistan

Objective: To explore RNA dependent RNA polymerase of Chikungunya virus(CHIKV) and develop T cell based epitopes with high antigenicity and good binding affinity for the human leukocyte antigen(HLA) classes as targets for epitopes based CHIKV vaccine. Methods: In this study we downloaded 371 non-structural protein 4 protein sequences of CHIKV belonging to different regions of the world from the US National Institute of Allergy and Infectious Diseases(NIAID) virus pathogen resource database. All the sequences were aligned by using CLUSTALW software and a consensus sequence was developed by using Uni Pro U Gene Software version 1.2.1. PropredⅠand Propred software were used to predict HLAⅠ and HLAⅡ binding promiscuous epitopes from the consensus sequence of non-structural protein 4 protein. The predicted epitopes were analyzed to determine their antigenicity through Vaxijen server version 2.0. All the HLAⅠ binding epitopes were scanned to determine their immunogenic potential through the Immune Epitope Database(IEDB). All the predicted epitopes of our study were fed to IEDB database to determine whether they had been tested earlier. Results: Twenty two HLA class Ⅱ epitopes and eight HLA classⅠepitopes were predicted. The promiscuous epitopes WMNMEVKII at position 486–494 and VRRLNAVLL at 331–339 were found to bind with 37 and 36 of the 51 HLA class Ⅱ alleles respectively. Epitope MANRSRYQS at position 58–66 and epitopes YQSRKVENM at positions 64–72 were predicted to bind with 12 and 9 HLAⅠI alleles with antigenicity scores of 0.754 9 and 1.013 0 respectively. Epitope YSPPINVRL was predicted to bind 18 HLAⅠ alleles and its antigenicity score was 1.425 9 and immunogenicity score was 0.173 83. This epitope is very useful in the preparation of a universal vaccine against CHIKV infection. Conclusions: Epitopes reported in this study showed promiscuity, antigenicity as well as good binding affinity for the HLA classes. These epitopes will provide the baseline for development

关键词： Chikungunya virus Epitope vaccine HLA binding T cell epitopes

Phytochemical analysis,antioxidant,acetylcholinesterase,andα-amylase inhibitors from Hippeastrum hybridum extract

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Journal of Traditional Chinese Medicine 2024年第3期44卷 496-504页

作者： Naila sher Mushtaq Ahmed Nadia Mushtaq Department of Biotechnology University of Science and Technology Bannu-KPK 28100Pakistan Department of Botany University of Science and Technology Bannu-KPK 28100Pakistan

OBJECTIVE:To investigate the effects of Hippeastrum hybridum(HH)as a free radical scavenger,and an inhibitor of the two enzymes i-e Alpha-amylase(α-amylase)and acetylcholinesterase(AChE).METHODS:In this study,HH plant was preliminary analyzed for phytochemical screening and then tested for its antioxidant,anti-α-amylase,and anti-AChE efficiency via standard ***:Phytochemical analysis shows the existence of different compounds;while Coumarins and quinones were *** total phenolic,flavonoid,and tannins content were found to be(78.52±0.69)mg GAE/g,(2.01±0.04)mg RUE/g,and(58.12±0.23)mg TAE/g of plant extract respectively.28.02%±0.02%alkaloid and 2.02%±0.05%saponins were present in the HH *** HH extract showed the anti-oxidant property with IC50(50%inhibition)of(151.01±0.13)(HH),(79.01±0.04)(Ascorbic acid)for ferric reducing,(91.48±0.13)(HH),(48.02±0.11)(Ascorbic acid)against Ammonium molybdenum,(156.02±0.31)(HH),(52.38±0.21)(Ascorbic acid)against DPPH,136.01±0.21(HH),52.02±0.31(Ascorbic acid)against H_(2)O_(2),and 154.12±0.03(HH),(40.05±0.15)(Ascorbic acid)μg/mL against ABTS *** analysis indicated that HH caused a competitive type of inhibition ofα-amylase(V_(max)remained constant and Km increases from 10.65 to84.37%)while Glucophage caused the un-competitive type of inhibition i-e both Km and V_(max)decreased from40.49 to 69.15%and 38.86 to 69.61%*** K_(i),(inhibition constant);K_(I),(dissociation constant),K_(m),(Michaelis-Menten constant),and IC50 were found to be62,364,68.1,and 38.08±0.22 for HH and 12,101.05,195,34.01±0.21 for ***,HH causes an anon-competitive type of inhibition of AChE i-e Km remains constant while V_(max)decreases from 60.5%to74.1%.The calculated K_(i),K_(I),K_(m),and IC50 were found to be 32,36.2,0.05,and 18.117±***:From the current results,it is concluded that HH extract contains bioactive compounds,and could be a good alternative to controlling oxidant

关键词： Hippeastrum hybridum phytochemicals antioxidant alpha-amylase acetylcholinesterase

Phytochemical composition, biological potential and enzyme inhibition activity of Scandix pecten-veneris L.

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2018年第2期19卷 120-129页

作者： Abdul WAHAB Syed Aleem JAN Abdur RAUF Zia ur REHMAN Zahid KHAN Aftab AHMED Fatima SYED sher zaman SAFI Hamayun KHAN Muhammad IMRAN Department of Chemistry Islamia College University Biochemistry Section Institute of Chemical Sciences University of Peshawar Department of Chemistry University of Swabi Department of Botany Islamia College University State Key Laboratory of Chemical Resource Engineering College of Life Science and TechnologyBeijing University of Chemical Technology Interdisciplinary Research Center in Biomedical Materials COMSATS Institute of Information Technology

Objective： Scandix pecten-veneris L. is a less studied wild edible herb and is considered an extinct plant species in many parts of the world. This study was designed to evaluate its phytochemical composition and biological potential of S. pecten-veneris L. Methods： Phytochemicals including alkaloids, fiavonoids, polyphenols, and tannins were determined in extracts of S. pecten-veneris. Antioxidant activity was determined using 2,2-diphenyl-1- picrylhydrazyl （DPPH）, while reducing power was tested by ferric reducing/antioxidant power （FRAP） assay. Antimi- crobial activity against seven bacterial and four fungal strains was evaluated using agar well diffusion assay. Enzymes inhibition study was performed for urease, phosphodiesterase-I, and catalase-II. Results： S. pecten-veneris showed moderate antiradical activity and reducing potential of hydroxyl radicals to about 20% of the initial value. The antiox- idant activity of various extracts of S. pecten-veneris showed a linear correlation with total phenolic contents in the order of water〉n-butanol〉chloroform〉ethyl acetate〉methanol extracts. S. pecten-veneris leaves showed the highest inhibitory activity against Staphylococcus aureus while the highest antifungal activity was observed against Candida albicans. The plant extract was most potent against urease enzymes but showed moderate activity against phosphodiestrase-I and carbonic anhydrase-II. Conclusions： Our data demonstrate that in addition to its culinary uses, S. pecten-veneris has good medicinal potential and hence could be used for treating some specific health ailments.

关键词： Scandix pecten-veneris L. Phytochemical composition Antioxidant activity Antimicrobial potential Enzyme inhibition

眼血流的变化对青光眼病情进展的影响（英文）

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国际眼科杂志 2017年第3期17卷 394-398页

作者： sher zaman Safi Mamoona Noreen Muhammad Imran Yasir Waheed Muhammad Imran Amir Miraj Ul Hussain Shah Nawshad Muhammad 拉合尔大学巴基斯坦信息技术学院生物医学材料跨学科研究中心巴基斯坦拉合尔54000 女子大学巴基斯坦木尔坦60000 皇家商学院卫生及相关学科学院医学实验室科学系巴基斯坦拉合尔54000 基金大学医学院巴基斯坦伊斯兰堡44000 白沙瓦大学化学系生物化学部巴基斯坦白沙瓦25000

青光眼是由多种因素引起的神经退行性疾病,眼压过高会损害视神经而导致永久性视力丧失。虽然青光眼的基本病理生理机制尚未确定,但眼组织如视神经,视网膜,脉络膜以及虹膜的血流改变是青光眼发病的重要危险因素。由于不同因素所引发的视... 详细信息

青光眼是由多种因素引起的神经退行性疾病,眼压过高会损害视神经而导致永久性视力丧失。虽然青光眼的基本病理生理机制尚未确定,但眼组织如视神经,视网膜,脉络膜以及虹膜的血流改变是青光眼发病的重要危险因素。由于不同因素所引发的视神经损害的有限认知,测量方法和治疗方面缺乏,人们对青光眼的理解存在障碍。尽管研究人员在不断地积累证据,力证眼血流的变化在青光眼发病机制中起着重要的作用,但大部分情况下,对于眼血流的变化和青光眼的患病风险之间的关系,他们都持有多样甚至矛盾的结论。本文中,我们回顾了青光眼的不同方面以及眼血流在疾病发展中的影响。

关键词：眼血流青光眼疾病进展

Influence of edaphic factors on distribution and condition of Himalayan silver birch(Betula utilis ***)communities in the northwestern Indian Himalayas

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Journal of Mountain Science 2024年第2期21卷 590-606页

作者： Khashti DASILA Renu RAWAL Tanay BARMAN sher Singh SAMANT Anita PANDEY Veena PANDE G.B.Pant National Institute of Himalayan Environment Almora 263643India Centre of Excellence on Sustainable Land Management Indian Council of Forestry Research and EducationDehradun 248006India Uttarakhand State Council for Science&Technology Dehradun 248015India Department of Biotechnology Graphic Era(Deemed to be University)Dehradun 248002India Department of Biotechnology Kumaun UniversityNainital 263136India

The basic concept of phytosociology is crucial for the assessment of species composition and dynamic ecological succession of forests supporting ecological services,functions,disturbance,and resilience that lead to the development of integrated areas such as ecological niche modeling and contribute to identifying the valuable bio-indicators which can be used in framing conservation and management *** is one of the most dominant tree species of treeline ecotone in the Himalayan *** species is also considered as indicator species for monitoring the past and recent climate change *** current study was carried out in the natural populations of *** from the sub-alpine zone of North-western Indian *** birch dominated forest harbors a total of 305 plant species comprising Angiosperms(51 families,160 genera and 277 species),Gymnosperms(03 families,05 genera and 07 species)and Pteridophytes(07 families,11 genera and 21 species)with Asteraceae,Ranunculaceae and Rosaceae as dominant *** forests are found dominant in shady moist habitat and North West *** characteristics,anthropogenic and developmental activities affect the population structure of *** and associated ***,the species has fair regeneration status in the study *** acidic nature of soil pH and spatial variation in edaphic characteristics may be due to geographical differences,rooting patterns and litter accumulation of below and above-ground *** estimation of a representative population of *** from each site showed that TAGBD,TCD and TBD were found maximum in ST3(Hamta Pass II site).The CCA analysis determined that environmental variables such as altitude,organic matter,available phosphorous,organic carbon,available nitrogen,and electrical conductivity played a significant role in determining tree species composition and distribution in *** dominated forests.

关键词： Species composition Indicator species Biomass North-western Indian Himalaya Regeneration Environmental variables

Control of Nozzle Flow Using Rectangular Ribs at Sonic and Supersonic Mach Numbers

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Fluid Dynamics & Materials Processing 2024年第8期20卷 1847-1866页

作者： Vigneshvaran Sethuraman Parvathy Rajendran sher Afghan Khan Abdul Aabid Muneer Baig School of Aerospace Engineering Universiti Sains MalaysiaEngineering CampusNibong TebalPulau Pinang14300Malaysia Department of Mechanical and Aerospace Engineering Faculty of EngineeringInternational Islamic University MalaysiaKuala Lumpur53100Malaysia Department of Engineering Management College of EngineeringPrince Sultan UniversityP.O.Box 66833Riyadh11586Saudi Arabia

This study deals with base pressure management in a duct for various values of the Mach number(M),namely,Mach number corresponding to sonic and four supersonic *** addition to the Mach number,the nozzle pressure ratio(NPR),the area ratio,the rib dimension,and the duct length are influential *** following specific values are examined at M=1,1.36,1.64,and 2,and NPRs between 1.5 and *** base pressure is determined by positioning ribs of varying heights at predetermined intervals throughout the length of the square *** the level of expansion is varied,it is seen that the base pressure initially drops for overexpanded flows and increases for under-expanded *** ribs are present,the flow field in the duct and pressure inside the duct fluctuate as the base pressure ***-expanded flows can achieve a base pressure value that is suitably high without experiencing excessive changes in the duct flow in terms of static pressure if a rib height around 10%of the duct height close to the nozzle exit is *** rib passive control does not negatively affect the duct’s flow field.

关键词： Base pressure internal flows ribs suddenly expanded flow wall pressure

Effect of Sweptback Angle of a Delta Wing on Surface Pressure Distribution at Supersonic Mach Numbers

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Fluid Dynamics & Materials Processing 2024年第10期20卷 2353-2376页

作者： Shamitha Shetty Asha Crasta sher Afghan Khan Abdul Aabid Muneer Baig Mathematics Department Mangalore Institute of Technology and EngineeringVisvesvaraya Technological UniversityNear MoodabidreMangaluruKarnataka574225India Nitte Meenakshi Institute of Technology Visvesvaraya Technological UniversityBangalore560064India Department of Mechanical and Aerospace Engineering Faculty of EngineeringInternational Islamic University MalaysiaKuala Lumpur53100Malaysia Department of Engineering Management College of Engineering Prince Sultan UniversityP.O.Box 66833Riyadh11586Saudi Arabia

The purpose of this work is to shed light on the effect of the pivot position on the surface pressure distribution over a 3D wing in different flight *** study is intended to support the design and development of aerospace vehicles where stability analysis,performance optimization,and aircraft design are of primary *** following parameters are considered:Mach numbers(M)of 1.3,1.8,2.3,2.8,3.3,and 3.8,angle of incidence(θ)in the range from 5°to 25°,pivot position from h=0.2 to *** results of the CFD numerical simulations match available analytical data,thereby providing evidence for the reliability of the used *** findings provide valuable insights into the relationship between the surface pressure distribution,the Mach number and the angle of incidence.

关键词： Mach number angles of incidence stability analysis performance optimization