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Protein & Cell 2013年第3期4卷 220-230页

作者： shahina akhter MdMashiar Rahman Hyun Seo Lee Hyeon-Jin Kim Seong-Tshool Hong Department of Microbiology and Genetics and Institute for Medical Science Chonbuk National University Medical SchoolJeonju 561-712South Korea JINIS BDRD Institute JINIS Biopharmaceuticals Co.948-9 DunsanBongdongWanju 565-902JeollabukdoSouth Korea

Recent advances in hematopoietic stem cells(HSCs)expansion by growth factors including angiopoietin-like proteins(Angptls)have opened up the possibility to use HSCs in regenerative ***,the unavailability of true in vitro HSCs expansion by these growth factors has limited the understanding of the cellular and molecular mechanism of HSCs ***,we report the functional role of mouse Angptls 1,2,3,4,6 and 7 and growth factors SCF,TPO,IGF-2 and FGF-1 on purified mouse bone-marrow(BM)Lineage-Sca-1+(Lin-Sca-1+)*** recombinant retroviral transduced-CHO-S cells that secrete Angptls in serum-free medium were used alone or in combination with growth factors(SCF,TPO,IGF-2 and FGF-1).None of the Angptls stimu-lated HSC proliferation,enhanced or inhibited HSCs colony formation,but they did support the survival of *** contrast,any of the six Angptls together with saturating levels of growth factors dramatically stimulated a 3-to 4.5-fold net expansion of HSCs compared to stimulation with a combination of those growth factors *** findings lead to an understanding of the basic function of Angptls on signaling pathways for the survival as well as expansion of HSCs in the bone marrow niche.

关键词： hematopoietic stem cells angiopoietin-like proteins growth factors survival ex vivo expansion cell culture

Partially Overlapping Channel Assignment Using Bonded and Non-Bonded Channels in IEEE 802.11n WLAN

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Computers, Materials & Continua 2022年第5期71卷 3161-3178页

作者： MdSelim Al Mamun Fatema akhter Graduate School of Natural Science and Technology Okayama UniversityOkayama700-8530Japan Computer Science and Engineering Jatiya Kabi Kazi Nazrul Islam UniversityMymensingh2224Bangladesh

Nowadays,wireless local area network(WLAN)has become prevalent Internet access due to its low-cost gadgets,flexible coverage and hasslefree simple wireless *** facilitates wireless Internet services to users with mobile devices like smart phones,tablets,and laptops through deployment of multiple access points(APs)in a network *** AP operates on a frequency band called *** wireless standard such as IEEE 802.11n has a limited number of channels where frequency spectrum of adjacent channels overlaps partially with each *** a crowded environment,users may experience poor Internet services due to channel collision i.e.,interference from surrounding APs that affects the performance of the WLAN ***,it becomes a challenge to maintain expected performance in a crowded environment.A mathematical model of throughput considering interferences from surrounding APs can play an important role to set up a WLAN system *** set up,assignment of channels considering interference can maximize network *** this paper,we investigate the signal propagation of APs under interference of partially overlapping channels for both bonded and non-bonded ***,a throughput estimation model is proposed using difference of operating channels and received signal strength indicator(RSSI).Then,a channel assignment algorithm is introduced using proposed throughput estimation ***,the efficiency of the proposal is verified by numerical experiments using *** results show that the proposal selects the best channel combination of bonded and non-bonded channels that maximize the performance.

关键词： Wireless local area network partially overlapping channel throughput estimation model channel assignment algorithm

Ultrasonic Study of Basic αr-Amino Acids in Different Acetate Salt Solutions at Different Temperatures

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Chinese Journal of Chemistry 2011年第4期29卷 669-678页

作者： Siddique Jamal akhter Naqvi, Saeeda Department of Chemistry Aligarh Muslim University Aligarh 202002 ( U.P.) India

The ultrasonic velocity （U）, has been measured for three a-amino acids, namely L-lysine monohydrochloride, L-arginine and L-histidine in solutions （1 mol/L aqueous） of sodium acetate （SA）, potassium acetate （PA） and calcium acetate （CA） at different temperatures （303.15, 308.15, 313.15, 318.15 and 323.15 K）. With the help of these results various ultrasonic derived parameters, viz. isentropic compressibility （Ks）, change in isentropic compressibility （△K5）, relative change in isentropic compressibility （△Kr）, specific acoustic impedance （Z）, relative association （RA）, and apparent molal compressibility （Фks） have been estimated. The results have been interpreted in the light of intermolecular interactions between solute and solvent.

关键词： ultrasonic velocity (U) amino acid salt effect isentropic compressibility organic salt

MXenes:A comprehensive review of synthesis,properties,and progress in supercapacitor applications

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Journal of Materiomics 2023年第6期9卷 1196-1241页

作者： Raheela akhter Shrikant S.Maktedar Materials Chemistry&Engineering Research Laboratory Department of ChemistryNational Institute of TechnologySrinagar190006J&K(UT)India

MXenes,a class of two-dimensional materials,have garnered significant attention due to their unique properties and versatile applications in various *** review provides a comprehensive overview of MXene synthesis methods,highlighting their distinctive layered structure and tunable properties through surface *** focus then shifts to their remarkable role in supercapacitor *** exhibit high electrical conductivity,large surface areas,and tailored surface chemistry,making them promising candidates for energy storage in *** paper discusses the interplay of electric double-layer capacitance and pseudocapacitance mechanisms within MXenebased electrodes,detailing recent research efforts aimed at optimizing their energy storage *** a combination of theoretical insights and experimental findings,the potential of MXenes to revolutionize supercapacitor technology emerges,offering prospects for high-energy-density and long-lasting energy storage ***,this review highlights recent advances in MXenebased supercapacitors,including novel electrode designs,electrolyte engineering,and hybrid materials,showcasing the dynamic evolution of MXene-based supercapacitor *** comprehensive overview aims to provide a thorough understanding of MXenes'synthesis,properties,and their pivotal role in advancing supercapacitor technology,while also encompassing the latest breakthroughs in this rapidly evolving field.

关键词： MXenes Bimetallic MXenes Supercapacitor Charge storage mechanism Microsupercapacitor Prelithiation

Uses of Invasive Alien Plant Species in Rema-Kalenga Wildlife Sanctuary of Bangladesh

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Journal of Mountain Science 2010年第4期7卷 380-385页

作者： Md.Parvez Rana Fahima akhter Department of Forestry and Environmental Science Shahjalal University of Science and Technology Department of Accounting and Information System University of Chittagong

An exploratory survey was conducted on the uses and role of invasive alien species(IAS) to local livelihoods in the Rema-Kalenga Wildlife Sanctuary in the northeastern hilly region of *** was sampled in 50 quadrates,each 10 m×10 m,and 25 line transects,each 50 m×20 m,through a combination of random and systematic *** discussions were also arranged with fifty local inhabitants(17 % of the total inhabitants) to learn the various uses of IAS.A total of 17 alien plant species belonging to 10 different families,of which Leguminosae constitutes the highest number(5 species),include tree(53%) followed by herb(12%),shrub(12%) and others(weed,climber and palm).The majority of the identified species were found to be used for fuel,followed by timber production,medicinal or curative uses,fodder,and many *** addition to providing various forest products,alien tree species planted in forest plantation help provide many vital ecosystem services such as soil amelioration through nitrogen *** is true that the alien species have some negative impacts on local ecosystems,and not all of them are ***,a national programme must be initiated to distinguish the harmful from the harmless species and to identify the uses and impacts of the former and latter.

关键词： Invasive alien species Biodiversity Livelihoods Rema-Kalenga Wildlife sanctuary Bangladesh

Integrated geoscience databanks for interactive analysis and visualization

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International Journal of Digital Earth 2013年第S2期6卷 41-49页

作者： Khalid Amin Khan Gulraiz akhter Zulfiqar Ahmad K-tron Research Inc. RawalpindiPakistan Department of Earth Sciences Quaid-i-Azam UniversityIslamabadPakistan

There has been a worldwide revolution in geoscientific data availability and *** effectively infinite and instantaneous free access to geoscientific data from the World Wide System of Geoscience Data Centers and Virtual Observatories is *** addition,national databanks and commercially available large exploration data-sets also *** distributed data resources impose challenges for the future to move toward their objective integration and visualization to discover new *** advancements can facilitate meaningful interpretations and decision-making for the benefit of society at global and local *** article presents the Digital Earth initiative at a national level to address multiple domains,such as effective management of natural resources,interactive planning of exploration activities and monitoring,mapping and mitigation of natural *** discusses a distributed geospatial data infrastructure and its importance in geoscientific data integration for efficient and interactive data retrieval,analysis and *** examples are presented to demonstrate the advantages of integrated visualization in geoscientific analysis.

关键词： distributed data geospatial data integration spatial data infrastructure data analysis visualization digital country

Protein ubiquitination in plant peroxisomes

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Journal of Integrative Plant Biology 2023年第2期65卷 371-380页

作者： Delara akhter Yuchan Zhang Jianping Hu Ronghui Pan State Key Laboratory of Rice Biology Zhejiang Provincial Key Laboratory of Crop Genetic ResourcesCollege of Agriculture and Biotechnology&ZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang UniversityHangzhou 310058/311200China Zhejiang Laboratory Hangzhou 311121China Department of Genetics and Plant Breeding Sylhet Agricultural UniversitySylhet 3100Bangladesh Department of Energy Plant Research Laboratory and Plant Biology Department Michigan State UniversityEast LansingMichiganUSA Department of Plant Biology Michigan State UniversityEast LansingMichiganUSA

Protein ubiquitination regulates diverse cellular processes in eukaryotic organisms,from growth and development to stress *** subjected to ubiquitination can be found in virtually all subcellular locations and organelles,including peroxisomes,singlemembrane and highly dynamic organelles ubiquitous in *** contain metabolic functions essential to plants and animals such as lipid catabolism,detoxification of reactive oxygen species(ROS),biosynthesis of vital hormones and cofactors,and *** peroxisomes possess a complex proteome with functions varying among different tissue types and developmental stages,and during plant response to distinct environmental ***,how these diverse functions are regulated at the post-translational level is poorly understood,especially in *** this review,we summarized current knowledge of the involvement of protein ubiquitination in peroxisome protein import,remodeling,pexophagy,and metabolism,focusing on plants,and referencing discoveries from other eukaryotic systems when *** on previous ubiquitinomics studies,we compiled a list of 56 ubiquitinated Arabidopsis peroxisomal proteins whose functions are associated with all the major plant peroxisomal metabolic *** discovery suggests a broad impact of protein ubiquitination on plant peroxisome functions,therefore substantiating the need to investigate this significant regulatory mechanism in peroxisomes at more depths.

关键词： peroxins peroxisome peroxisome biogenesis peroxisome metabolism pexophagy ubiquitination

Analysis of Distance-Based Topological Polynomials Associated with Zero-Divisor Graphs

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Computers, Materials & Continua 2022年第2期70卷 2895-2904页

作者： Ali Ahmad Roslan Hasni Nahid akhter Kashif Elahi College of Computer Sciences and Information Technology JazanJazan UniversitySaudi Arabia Faculty of Ocean Engineering Technology and Informatics University Malaysia TerengganuKuala Terengganu21030TerengganuMalaysia Department of Mathematics Govt.College UniversityLahorePakistan Deanship of E-learning and Information Technology Jazan UniversityJazanSaudi Arabia

Chemical compounds are modeled as *** atoms of molecules represent the graph vertices while chemical bonds between the atoms express the *** topological indices representing the molecular graph corresponds to the different chemical properties of *** a,b be are two positive integers,andΓ(Z_(a)×Z_(b))be the zero-divisor graph of the commutative ring Z_(a)×Z_(b).In this article some direct questions have been answered that can be utilized latterly in different *** study starts with simple computations,leading to a quite complex ring theoretic problems to prove certain *** theory of finite commutative rings is useful due to its different applications in the fields of advanced mechanics,communication theory,cryptography,combinatorics,algorithms analysis,and *** this paper we determine the distance-based topological polynomials and indices of the zero-divisor graph of the commutative ring Z_(p^(2))×Z_(q)(for p,q as prime numbers)with the help of graphical structure *** study outcomes help in understanding the fundamental relation between ring-theoretic and graph-theoretic properties of a zero-divisor graphΓ(G).

关键词： Zero divisor graph Wiener index Hosoya polynomial (modified)Schulz index (modified)Schulz polynomial

Effect of Minor Alloying on Crystallization Behavior and Thermal Properties of Zr_(64.5)Ni_(15.5)Al_(11.5)Cu_(8.5) Bulk Amorphous Alloy

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Journal of Materials Science & Technology 2011年第6期27卷 534-538页

作者： Muhammad Iqbal Javed Iqbal akhter Haifeng Zhang Zhuangqi Hu MicrostructuralStudies Group Physics Division Pakistan Institute of Nuclear Science and Technology (PINSTECH) P.O. Nilore Islamabad Pakistan Shenyang Nationel Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Minor alloying plays an important role in the synthesis and improvement of thermal stability of bulk metallic glasses（BMGs）.The present study was conducted to investigate the effect of minor additions of Y,Ti and Nb on the crystallization behavior and the thermal properties of Zr64.5Ni15.5Al11.5Cu8.5 *** parameters and the activation energies for crystallization were calculated for four（Zr0.645Ni0.155Al0.115-Cu0.085）100-xMx（M=Y,Ti and Nb,while x=0,2 at.） *** present alloys have wide supercooled liquid region of ≥87 *** activation energy was found to be greater than 300 kJ/mol for the base *** crystalline phases were identified in the samples annealed at 823 K for 20 *** glass transition temperature（Trg） and other thermal parameters such as γ,δ and β were improved by Y and Ti *** addition resists crystallization below annealing temperature 713 K,however,its effect on thermal properties is not very promising.

关键词： Activation energy Thermal properties Glass-forming ability Thermal stability Precipitation Microstructure

Unsteady RANS simulation of wind flow around a building shape obstacle

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Building Simulation 2022年第2期15卷 291-312页

作者： Sheikh Hassan Md.Mamun Molla Preetom Nag Nasrin akhter Amirul Khan Department of Mathematics&Physics North South UniversityDhaka 1229Bangladesh Department of Mathematics Dhaka University of Engineering&TechnologyGazipur 1708Bangladesh School of Civil Engineering University of LeedsLeeds LS29JTUK

This work aims to find the origin and connection of the surface,near-wake,and far-wake structures in the flow encompassing a high-rise building for a high Reynolds *** origin and interconnection of the stream-wise tip vortices,with the other components of the wake,is analysed in this study for the current *** Unsteady Reynolds Averaged Navier-Stokes equations(URANS)together with the realizable k-εturbulence model have been used in this investigation to study the turbulent wake flow following a ground-surface-attached square shape building.A moderately big obstacle aspect ratio of 4,a Reynolds number of 12,000,and a thin evolving boundary layer thickness have been used in the flow *** designed flow addresses the reversed-flows at the outlet during computation to improve the accuracy of the realizable k-e *** Reynolds stress components are retrieved using the Boussinesq *** wake’s principal compositions,including span-wise-side eddies and area of high stream-wise vorticity in the uppermost portion of the wake,are illustrated by both three-dimensional(3D)representations and planner projections of the mean flow distributions.A braided vortex formation,composed of asymmetric hairpin vortexes,is witnessed in the far-wake *** association of the near-wake vortex structures with the far-wake and near-wall flow,which is associated with the flow strengths,is also *** this investigation,few areas of large stream-wise vorticity magnitude,like tip vortexes,are correlated to the 3D curving of the fluid motion,and tip vortices did not continuously reach to the free end part of the *** 3D fluid motion interpretation,which combined several measurements of the flow distribution encompassing the cylinder,shows that the time-averaged near-wake structures are formed of two segments of distinct source and section of ***,addressing reversed-flow during computation shows notable improvement in the results.

关键词： turbulent wake vortex shedding flow structures tip vortexes model building URANS turbulent boundary layer