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Materials Sciences and Applications 2014年第13期5卷 932-942页

作者： Mohamed Ali Ahmed kasim el-sayed rady Kamel Mohamed el-Shokrofy Ahmed Abo Arais Mohamed Said Shams Materials Science Laboratory Physics Department Faculty of Science Cairo University Giza Egypt Engineering Basic Sciences Department Faculty of Engineering Menoufia University Shebin El-Kom Egypt Department of Physics and Engineering Mathematics Faculty of Electronic Engineering Menoufia University Al Minufya Egypt

The effect of Zn2+ ions on the microstructure and electrical properties of Mn1-xZnxFe2O4 (0.0 ≤ x ≤ 0.5 in steps of 0.1) through a solid state reaction has been investigated. The structural properties have been investigated using X-ray diffraction (XRD) technique. The XRD analysis confirms that all samples are in a single-phase cubic spinel structure. The experimental lattice parameter (aexp) was decreased with increasing Zn2+ ions substitution due to the smaller ionic radius of zinc content. The crystallite size (t) of samples was estimated by Scherrer’s formula and found in the range (90 - 115 nm). Dc electrical resistivity and Seebeck voltage coefficients were measured as a function of temperature using the two probe methods. The temperature variation of resistivity exhibits two breaks, each break referring to a change in the activation energy. The Curie temperature estimated from dc resistivity measurement decreases with increasing Zn2+ ions. Seebeck voltage coefficient measurements reveal n-type conduction for all samples.

关键词： Mn-Zn Ferrite XRD Microstructure IR DC Resistivity Seeback Coefficient

Dynamic Analysis of the Multi-state Reliability System with Priority Repair Discipline

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 665-694页

作者： Aihemaitijiang YUMAIER Ehmet kasim College of Mathematics and Systems Science Xinjiang UniversityUrumqi 830046China

This paper considers a multi-state repairable system that is composed of two classes of components,one of which has a priority for ***,we investigate the well-posedenss of the system by applying the operator semigroup ***,using Greiner’s idea and the spectral properties of the corresponding operator,we obtain that the time-dependent solution of the system converges strongly to its steady-state solution.

关键词： multi-state system C0-semigroup Dirichlet operator well-posedness asymptotic behavior

The two sides of chromosomal instability:drivers and brakes in cancer

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1595-1624页

作者： Rendy Hosea Sharon Hillary Sumera Naqvi Shourong Wu Vivi kasim Key Laboratory of Biorheological Science and Technology Ministry of EducationCollege of BioengineeringChongqing UniversityChongqing 400045China The 111 Project Laboratory of Biomechanics and Tissue Repair College of BioengineeringChongqing UniversityChongqing 400044China Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment Chongqing University Cancer HospitalChongqing UniversityChongqing 400030China

Chromosomal instability(CIN)is a hallmark of cancer and is associated with tumor cell *** triggers a chain reaction in cells leading to chromosomal abnormalities,including deviations from the normal chromosome number or structural changes in *** arises from errors in DNA replication and chromosome segregation during cell division,leading to the formation of cells with abnormal number and/or structure of *** in DNA replication result from abnormal replication licensing as well as replication stress,such as double-strand breaks and stalled replication forks;meanwhile,errors in chromosome segregation stem from defects in chromosome segregation machinery,including centrosome amplification,erroneous microtubule-kinetochore attachments,spindle assembly checkpoint,or defective sister chromatids *** normal cells,CiN is deleterious and is associated with DNA damage,proteotoxic stress,metabolic alteration,cell cycle arrest,and ***,despite these negative consequences,CiN is one of the hallmarks of cancer found in over 90%of solid tumors and in blood ***,CiN could endow tumors with enhanced adaptation capabilities due to increased intratumor heterogeneity,thereby facilitating adaptive resistance to therapies;however,excessive CiN could induce tumor cells death,leading to the"just-right"model for CIN in *** the complex nature of CIN is crucial for understanding the dynamics of tumorigenesis and for developing effective anti-tumor *** review provides an overview of causes and consequences of CIN,as well as the paradox of CIN,a phenomenon that continues to perplex ***,this review explores the potential of CIN-based anti-tumor therapy.

关键词： chromosomal consequences thereby

Application of Polygonum minus Extract in Enhancing Drought Tolerance in Maize by Regulating Osmotic and Antioxidant System

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Phyton-International Journal of Experimental Botany 2024年第2期93卷 213-226页

作者： Mingzhao Han Susilawati kasim Zhongming Yang Xi Deng Md Kamal Uddin Noor Baity Saidi Effyanti Mohd Shuib Department of Land Management Faculty of AgricultureUniversiti Putra MalaysiaSerdang43400Malaysia Natural Medicines and Products Research Laboratory Institute of BioscienceUniversiti Putra MalaysiaSerdang43400Malaysia Department of Cell and Molecular Biology Faculty of Biotechnology and Biomolecular SciencesUniversiti Putra MalaysiaSerdang43400Malaysia

Drought stress is a major factor affecting plant growth and crop yield *** extracts as natural biostimulants hold great potential to strengthen plants to overcome drought *** explore the effect of Polygonum minus extract(PME)in enhancing drought tolerance in plants,a study was set up in a glasshouse environment using 10 different treatment *** foliar application were designed in CRD and effects were closely observed related to the growth,physiology,and antioxidant system changes in maize(Zea mays L.)under well-watered and drought *** seaweed extract(SWE)was used as a *** subjected to drought stress exhibited a significant reduction in fresh weight,dry weight,relative water content(RWC),and soluble sugar,but they stimulated the phenolic,flavonoid,proline,glutathione(GSH),malondialdehyde(MDA)and antioxidant enzyme(catalase,CAT;peroxidase,POD;superoxide dismutase,SOD)*** application of PME improved fresh and dry weight(FW:33.1%~41.4%;DW:48.0%~43.1%),chlorophyll content(Chl b:87.9%~100.76%),soluble sugar(23.6%~49.3%),and soluble protein(48.6%~56.9%)as well as antioxidant enzyme activities(CAT and POD)compared to CK under drought *** decreasing the level of ***,the mitigating effect of PME application with high concentration was more effective than those of *** study reveals that PME could alleviate drought stress by regulating osmoprotectant content and antioxidant defense system and can be used as an economical and environmentally friendly biostimulants for promoting maize growth under drought stress.

关键词： Drought biostimulants photosynthesis osmoprotectants antioxidants maize

Optimal transcorneal electrical stimulation parameters for preserving photoreceptors in a mouse model of retinitis pigmentosa

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Neural Regeneration Research 2024年第11期19卷 2543-2552页

作者： Sam Enayati Karen Chang Anton Lennikov Menglu Yang Cherin Lee Ajay Ashok Farris elzaridi Christina Yen kasim Gunes Jia Xie Kin-Sang Cho Tor Paaske Utheim Dong Feng Chen Schepens Eye Research Institute of Massachusetts Eye and Ear Department of OphthalmologyHarvard Medical SchoolBostonMAUSA Institute of clinical medicine Faculty of MedicineUniversity of OsloOsloNorway Department of Medical Biochemistry Oslo University HospitalUniversity of OsloOsloNorway Department of Ophthalmology Drammen HospitalVestre Viken Hospital TrustDrammenNorway Department of Histology and Embryology School of MedicineMarmara UniversityIstanbulTurkiye

Retinitis pigmentosa is a hereditary retinal disease that affects rod and cone photoreceptors,leading to progressive photoreceptor *** research supports the beneficial effect of electrical stimulation on photoreceptor *** study aims to identify the most effective electrical stimulation parameters and functional advantages of transcorneal electrical stimulation(tcES)in mice affected by inherited retinal ***,the study seeked to analyze the electric field that reaches the retina in both eyes in mice and post-mortem *** this study,we recorded waveforms and voltages directed to the retina during transcorneal electrical stimulation in C57BL/6J mice using an intraocular needle probe with rectangular,sine,and ramp *** investigate the functional effects of electrical stimulation on photoreceptors,we used human retinal explant cultures and rhodopsin knockout(Rho^(-/-))mice,demonstrating progressive photoreceptor degeneration with *** retinal explants isolated from the donors’eyes were then subjected to electrical stimulation and cultured for 48 hours to simulate the neurodegenerative environment in *** density was evaluated by rhodopsin *** vivo Rho^(-/-)mice were subjected to two 5-day series of daily transcorneal electrical stimulation using rectangular and ramp *** function and visual perception of mice were evaluated by electroretinography and optomotor response(OMR),*** was used to assess the morphological and biochemical changes of the photoreceptor and bipolar cells in mouse *** recordings indicated effective delivery of rectangular,sine,and ramp waveforms to the retina by transcorneal electrical stimulation,of which the ramp waveform required the lowest *** of the total conductive resistance of the post-mortem human compared to the mouse eyes indicated higher cornea-to-retina resistance in human *** tem

关键词： bipolar cells electrical stimulation neuroprotection photoreceptor degeneration retina retinal explants retinitis pigmentosa transcorneal electrical stimulation waveform

Olefin Polymerization Behavior of Titanium(IV) Complexes with Fluorinated and Non-fluorinated Aliphatic Phenoxyimine Ligands

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Chinese Journal of Polymer Science 2024年第1期42卷 52-62,I0007页

作者： Vladislav A.Tuskaev kasim F.Magomedov Svetlana Ch.Gagieva Dmitry A.Kurmaev Yulia V.Nelyubina Evgenii K.Golubev Maria D.Evseeva Viktor G.Vasil'ev Galina G.Nikiforova Mikhail I.Buzin Vyacheslav S.Bogdanov Boris M.Bulychev Department of Chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation Enikolopov Institute of Synthetic Polymer Materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iPrO) are situated in cis *** of activators(MMAO-12 and combinations Et_nAICl_(3-n)+Bu_(2)Mg) and outgoing ligand(Cl or iPrO) nature on the catalytic activity and properties of the resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iPrO) in the presence of Al/Mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(M_v) value in the range 1.1×10~6-7.1×10~6 Dalton(Da).The resulting UHMWPE can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million Da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

关键词： FI catalysts Titanium(IV) (Co)polymerization Al/Mg co-catalyst Ultra-high molecular weight polyethylene

近红外激发PLNPs/UCNPs纳米复合材料的制备及其性能研究

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近红外激发PLNPs/UCNPs纳米复合材料的制备及其性能研究

作者：鲁克曼·喀斯木（Lukman kasim）喀什大学

学位级别：硕士

研究人员在新型多功能纳米材料的研发上付出了诸多努力,并将其广泛应用于生物医学领域。其中,长余辉发光材料和上转换发光材料在生物成像、生物传感和癌症治疗等领域的发展,具有潜在应用前景。但是,长余辉发光材料和上转换发光材料的开... 详细信息

研究人员在新型多功能纳米材料的研发上付出了诸多努力,并将其广泛应用于生物医学领域。其中,长余辉发光材料和上转换发光材料在生物成像、生物传感和癌症治疗等领域的发展,具有潜在应用前景。但是,长余辉发光材料和上转换发光材料的开发仍然面临着一些挑战。部分长余辉发光材料中能量的耗尽可以被光激励持续发光策略恢复,但大部分长余辉发光材料充电效率差,发射强度和穿透深度仍然受到限制,满足不了在体内重复激发以便用于长期成像应用的需求;上转换发光材料内部的非辐射能量损失和其他损耗机制的存在,导致发光效率较低,并且发光时间有限。基于以上问题,可以通过发射波长在近红外第二（NIR-II）生物窗口的长余辉发光材料来解决长余辉发光穿透深度受到限制的问题;通过将长余辉发光材料和上转换发光材料的结合来解决长期成像应用的需求。在第一项工作中,我们采用水热合成法,制备了发射波长位于NIR-II生物窗口的Ni2+掺杂镓酸锌Zn1+2xGa2-2xO4:Nix2+（ZGO:Ni）长余辉发光材料,ZGO:Ni在1000～1500nm之间出现宽带发射峰。系统地研究了不同煅烧温度和p H值以及Ni2+不同掺杂比例对ZGO:Ni发光特性的影响。采用XRD、TEM、EDS、荧光光谱仪进行测试,对制备的ZGO:Ni进行了表征,并研究了其光致发光性能、余辉发光性能和发光机理。结果显示,通过优化煅烧温度和p H值以及Ni2+的掺杂量,确定了当ZGO:Ni的煅烧温度为1000℃、p H值为8、Ni2+的掺杂量1%时发光性能最佳,发射波长位于1290 nm处。在第二项工作中,我们构建了Zn Ga2O4:Ni2+/Na Er F4:Yb3+,Mn2+（ZGO:Ni/UCNPs）上转换长余辉纳米复合材料。我们采用水热合成法,制备了激发源为980 nm激光、发射波长在600-700 nm范围内的Na Er F4:Yb3+,Mn2+上转换发光材料,基于荧光共振能量转移体系,通过共价键将Zn Ga2O4:Ni2+与Na Er F4:Yb3+,Mn2+结合。所得到的复合材料用980 nm激光激活后,在1290 nm处呈现持续发光。这是由于980 nm激光激发后,Na Er F4:Yb3+,Mn2+的发射光谱与Zn Ga2O4:Ni2+的激发光谱有良好的重叠,使得Na Er F4:Yb3+,Mn2+中的Er3+和Zn Ga2O4:Ni2+中的Ni2+之间发生荧光共振能量转移。ZGO:Ni/UCNPs上转换长余辉纳米复合材料的构建,解决了光激励持续发光策略不能满足体内重复激发以供长期成像应用需求的问题。此外,因为复合材料的激发（980nm）和发射（1290 nm）波长位于生物NIR-I、NIR-II生物窗口内,适合用于深层组织的生物成像,因此,该复合材料在体内生物成像方面有巨大的应用潜力。

关键词：长余辉发光上转换发光上转换长余辉发光 NIR-Ⅱ生物窗口

Yellowing of fresh-cut spinach(Spinacia oleracea L.)leaves delayed by UV-B applications

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Information Processing in Agriculture 2017年第3期4卷 214-219页

作者： M.Ufuk kasim Rezzan kasim Kocaeli University Graduate School of Natural and Applied Sciences Vocational School of Arslanbey41285 KartepeKocaeliTurkiye

In present work,the effects of UV-B treatments on quality of fresh-cut spinach leaves were *** this purpose,spinach leaves grown in glasshouse were harvest,cleaned and placed into polystyrene foam dishes and wrapped by stretch *** packaging,freshcut spinach leaves were treated with UV-B irradiation and were stored at 5℃ temperature for 12 *** soluble solids,visual quality,L^*a^*b^* values,and also hue angle values of samples were determined during *** soluble solids content of samples in control group has been higher than those from samples in UV-B treatments,however,visual quality was lower than the other *** to L*values of the samples,it is found that lower ultraviolet irratiation(UV-B)treatments caused yellowing of samples,and also same result was obtained by b^* and a^* values of fresh-cut spinach ***,hue angles values of samples treated with UV-B for 6min was higher compared with the other ***,yellowing of fresh-cut spinach leaves was decreased,and visual quality scores of samples was increased through ultraviolet irradiation treatments.

关键词： Spinach Fresh-cut Ultraviolet irradiation(UV-B) Yellowing

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基于文献计量的新疆高校图书馆研究现状分析

科技资讯 2024年第10期22卷 235-239页

作者：冯璐璐吐尔洪·卡斯木卢函和田师范专科学校图书馆和田师范专科学校生地学院新疆和田848000

通过对新疆高校图书馆研究的相关文献进行计量分析,旨在了解当前新疆高校图书馆研究的现状,根据分析反馈的信息,探究和发现新疆高校图书馆研究的一些特点,为相关科研人员提供一定的借鉴和参考。下载中国知网、维普、万方数据库中新疆高... 详细信息

通过对新疆高校图书馆研究的相关文献进行计量分析,旨在了解当前新疆高校图书馆研究的现状,根据分析反馈的信息,探究和发现新疆高校图书馆研究的一些特点,为相关科研人员提供一定的借鉴和参考。下载中国知网、维普、万方数据库中新疆高校图书馆研究文献,汇总后清洗得到1368条符合主题的题录信息。结果表明:新疆高校图书馆研究热点主要集中在读者服务、资源建设与共享、馆员建设3个方面,近几年主要侧重特色馆藏、数据库等的资源建设,学科服务、流通服务等服务模式研究,微信平台公众号、图书荐购、立德树人、文化润疆、文化扶贫等的阅读推广活动,以及人力资源等方面;虽然新疆高校图书馆研究形成一定规模,但发文质量有待提高。

关键词：新疆高校图书馆文献计量研究热点发文趋势

Point Spectra of the Operator Corresponding to the M/M/1 Queueing Model with Working Vacation and Vacation Interruption

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Journal of Mathematical Research with Applications 2019年第1期39卷 75-88页

作者： Ehmet kasim Geni GUPUR College of Mathematics and Systems Science Xinjiang University

In this paper, we consider point spectra of the operator corresponding to the M/M/1 queueing model with working vacation and vacation interruption. We prove that the underlying operator has uncountable eigenvalues on the left real line and these results describe the point spectra of the operator. Then, we show that the essential growth bound of the C0-semigroup generated by the operator is 0 and therefore it is not quasi compact, the essential spectral bound of the C0-semigroup is equal to 1. Moreover, our results imply it is impossible that the time-dependent solution of the model exponentially converges to its steady-state solution.

关键词： M/M/1 queueing model working vacation and vacation interruption C0-semigroup eigenvalue essential spectral bound