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DFT investigation of half-metallic ferromagnetic rare earth based spinels mgho_(2)Z_(4)(Z=S,Se)

Journal of Rare Earths 2024年第1期42卷 121-128,I0005页

作者： maiza Zanib mumtaz manzoor N.A.Noor m.Waqas Iqbal mazia Asghar h.h.hegazy A.Laref Department of Physics Riphah International UniversityLahore CampusPakistan Research Centre for Advanced materials Science King Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Department of Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Department of Physics and Astronomy College of ScienceKing Saud UniversityRiyadh11451Saudi Arabia

half-metallic ferromagnetism,mechanical as well as thermoelectric properties for rare earth-based spinels mgho_(2)Z_(4)(Z=S,Se)were investigated using density functional theory(DFT).Structural optimization was done with Perdew-Burke-Ehrenzorf(PBE)sol-generalized gradient approximation(GGA)to calculate the lattice constant of both spinels comparable to experimental *** addition,Born stability criteria and negative formation energy show that our studied spinels are also structurally and dynamically stable in the cubic *** ferromagnetic(Fm)state stability,we also calculated the energy differences among Fm,antiferromagnetic(AFm),and non-magnetic(Nm)***,Curie temperatures of ferromagnetic phases were also *** used Trans-Blaha improved BeckeJohnson(TB-mBJ)potential functional for electronics as well as magnetic characteristics,which lead to the consistent explanation of half-metallic ferromagnetism,representing the whole band-occupancy in material with exact detail of density of states(DOS).The stable Fm state was examined in spinels due to the exchange splitting of ho cation consisting of p-d hybridizations compatible with the result achieved for electronics band structure and ***,spin magnetic moment was explained in terms of anion,cation,and sharing charge on studied *** addition,the calculated thermoelectric properties clearly show that operation range of these systems may be utilized by future experimental works for identifying the potential applications of these systems.

关键词： ho-based spinels DFT simulations mechanical parameters Electronic properties hm ferromagnetism Figure of merit

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COX-2 polymorphisms-765G→C and-1195A→G and colorectal cancer risk

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World Journal of Gastroenterology 2009年第36期15卷 4561-4565页

作者： Juliёt h hoff Rene hm te morsche hennie mJ Roelofs Elise mJ van der Logt Fokko m Nagengast Wilbert hm Peters Department of Gastroenterology Radboud University Nijmegen Medical Center6500 HB NijmegenThe Netherlands

AIm:To determine the possible modulating effect of the COX-2 polymorphisms,-765G→C and-1195A→G, on the risk of colorectal cancer(CRC)in a Dutch population. mEThodS:This case-control study includes 326 patients with CRC and 369 age-and gender-matched *** of the COX-2 polymorphisms -765G→C and-1195A→G were determined by polymerase chain reaction-based restriction fragment length ***-2 genotypes and haplotypes were analyzed and odds ratios with 95%confi- dence intervals were estimated by logistic regression. RESULTS:The-765GG genotype was associated with an increased risk of developing CRC(OR,1.45; 95%CI,1.03-2.04).No significant difference was observed in the genotype distribution of the-1195A→ G polymorphism between patients and *** GG/AC haplotype was present significantly less often in patients than in controls(OR 0.44;95%CI,0.22-0.85). When the AC,AG and GG haplotypes were investigated separately,the AC haplotype showed a tendency to be less frequent in patients than in controls(OR(AG/AC)0.78; 95%CI,0.57-1.06). CONCLUSION:The-765GG genotype is associatedwith an increased risk of developing CRC and the GG/ AC haplotype seems to protect against *** findings suggest a modulating role for the COX-2 polymorphisms-765G→C and-1195A→G in the development of CRC in a Dutch population.

关键词：基因多态性风险限制性片段长度多态性直肠癌 Logistic 环氧合酶-2 结肠聚合酶链反应

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Exploring tree diversity and stand structure of savanna woodlands in southeastern Sudan

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Journal of Arid Land 2020年第4期12卷 609-617页

作者： Ahmed m m hASOBA Ahmed A h SIDDIG Yousif E YAGOUB Faculty of Forest Sciences and Technology University of GeziraMadani 22212Sudan Faculty of Forestry University of KhartoumKhartoum North 13314Sudan Department of Environmental Conservation University of Massachusetts AmherstAmherst 01003USA

Savanna woodlands in Sudan host great biodiversity, provide a plethora of ecosystem goods and services to local communities, and sustain numerous ecological functions. Although the importance of the Acacia trees in these areas is well known, up-to-date information about these woodlands' diversity is limited and changes in their woody vegetation composition, density, diversity and relative frequency are not monitored over time. This study explored tree diversity and stand stage structure in Nuara Reserved Forest, a typical savanna woodland ecosystem in southeastern Sudan. A total of 638 circular sample plots(1000 m^2 for each) were established using a systematic sampling grid method. The distance between plots was 200 m. In each plot, all living trees with diameter at breast height(DBh) ≥5.00 cm were identified and counted, and their DBh values were recorded. From these data, tree composition, diversity, density and stage structure were assessed. There were 12,259 individual trees representing four species(Acacia seyal, Balanites aegyptiaca, Acacia Senegal and Acacia mellifera) that belong to two families. The dominant species was Acacia seyal. Average tree density was 191 trees/hm^2 and the Shannon-Weiner index for trees diversity was 0.204. Overall, young trees comprised 86.30% of the forest. The state of tree richness and density in the study area was low compared to other similar environments in the region and around the world. We recommended adoption of a proper management system that includes monitoring of woody vegetation diversity in this forest, and management actions to enhance tree diversity and sustain ecosystem services to local communities. In addition to care for the dominant Acacia seyal stands, more attention and conservation should be devoted to reestablishing Acacia senegal and Acacia mellifera trees because of their high ecological and economic values for local communities.

关键词： species diversity stand structure savanna woodland ecosystem forest monitoring forest management ecosystem services Nuara Reserved Forest

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Effect of Conductive Fillers on the Cyclic Stress-Strain and Nano-Scale Free Volume Properties of Silicone Rubber

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Chinese Journal of Polymer Science 2014年第5期32卷 558-567页

作者： m.h.Abd-El Salam S.El-Gamal m.mohsen D.m.Abd El-maqsoud Physics Department Faculty of Education Ain Shams University Physics Department Faculty of Science Ain Shams University

The effect of carbon black （CB） and graphite （G） powders on the macroscopic and nano-scale free volume properties of silicone rubber based on poly（di-methylsiloxane）（PDmS） was studied through thermal and cyclic mechanical measurements, as well as with positron annihilation lifetime spectroscopy （PALS）. The melting temperature of the composites （Tm） and the endothermic enthalpy of melting （Δhm） were estimated by differential scanning calorimetry （DSC）. Tm and the degree of crystallinity （χc） of PDmS composites were found to decrease with increasing the CB content. This can be explained due to the increase in physical cross-linking which results in a decrease in the crystallite thickness. Besides, χc was found to be dependent on the filler type. Cyclic stress-strain behavior of PDmS loaded with different contents of filler has been studied. mullins ratio （Rm） was found to be dependent on the filler type and content. It was found that, Rm increases with increasing the filler content due to the increase in physical cross-linking which results in a decrease in the size of free volume, as observed through a decrease of the o-Ps lifetime τ3 measured by PALS. moreover, the hysteresis in PDmS-CB composites was more pronounced than in PDmS-G composites. Furthermore, a correlation was established between the free volume Vf and the mechanical properties of PDmS composites containing different fillers. A negative correlation was observed between Vf and Rm.

关键词： Positron annihilation Positronium Free volume Si-rubber Composite Cyclic mechanical properties.

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Identification of serum proteins discriminating colorectal cancer patients and healthy controls using surface-enhanced laser desorption ionisation-time of flight mass spectrometry

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World Journal of Gastroenterology 2006年第10期12卷 1536-1544页

作者： Judith YmN Engwegen helgi h helgason Annemieke Cats Nathan harris Johannes mG Bonfrer Jan hm Schellens Jos h Beijnen Department of Pharmacy and Pharmacology The Netherlands Cancer Institute/Slotervaart hospital AmsterdamThe Netherlands Department of medical Oncology The Netherlands Cancer Institute/Antoni van Leeuwenhoek hospital AmsterdamThe Netherlands Department of Gastroenterology and hepatology The Netherlands Cancer Institute/Antoni van Leeuwenhoek hospital AmsterdamThe Netherlands Ciphergen Biosystems Inc. Freemont CaliforniaUnited States Department of Clinical Chemistry The Netherlands Cancer Institute/Antoni van Leeuwenhoek hospital AmsterdamThe Netherlands Utrecht University Faculty of Pharmaceutical Sciences Department of Biomedical analysisUtrechtThe Netherlands

瞄准：为颜色检测新浆液简历标记由浆液蛋白质与提高表面的激光解吸附作用 ionisation 介绍的表面的癌症(CRC )-- 飞行团分光术(SELDI-TOF mS ) 的时间。方法：二个独立浆液样品集合与 ProteinChip 技术独立被分析(集合 A：40 CRC+49 ... 详细信息

瞄准：为颜色检测新浆液简历标记由浆液蛋白质与提高表面的激光解吸附作用 ionisation 介绍的表面的癌症(CRC )-- 飞行团分光术(SELDI-TOF mS ) 的时间。方法：二个独立浆液样品集合与 ProteinChip 技术独立被分析(集合 A：40 CRC+49 健康控制；集合 B：37 CRC+31 健康控制) ，有一个弱阳离子的使用的芯片交换一半和缓冲区 ph 5。差别的歧视的力量表示了蛋白质与一个分类树算法被估计。产生分类树的敏感和特性被盲目地从集合 B 并且反过来也如此从集合 A 把数据用于产生的树获得。CRC 浆液蛋白质侧面也与从胸的那些相比，卵巢，前列腺，和非小的房间肺癌症。结果：mass-to-charge 比率(m/z ) 3.1x10 (3 ) ， 3.3x10 (3 ) ， 4.5x10 (3 ) ， 6.6x10 (3 ) 和 28x10 (3 ) 在最好执行的分类树上被用作分类器。树敏感和特性在 65% 和 90% 之间。大多数这些歧视的 m/z 价值在调查的另外的瘤类型也是不同的。m/z 3.3x10 (3 ) ，在大多数树上的主要分类器，是 6.6x10 (3 ) 的一种二倍地控告的形式 -Da 蛋白质。后者作为 apolipoprotein C-I 被识别。m/z 3.1x10 (3 ) 作为 apolipoprotein A-I 作为白朊，和 m/z 28x10 (3 ) 的 N 终端碎片被识别。结论：分类树模式分析跟随的 SELDI-TOF mS 是为为 CRC 发现新浆液标记的一种合适的技术。Biomarkers 能与高敏感和特性在独立样品集合被识别并且 reproducibly 检测了。尽管为 CRC 不特定，这些简历标记在监视的疾病和治疗有一个潜在的角色。

关键词：血清蛋白结肠癌光谱测定检查方法

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Independent and complementary bio-functional effects of CuO andGa_(2)O_(3) incorporated as therapeutic agents in silica-and phosphate-based bioactive glasses

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Journal of materiomics 2022年第4期8卷 893-905页

作者： T.Tite A.C.Popa B.W.Stuart h.R.Fernandes I.m.Chirica G.A.Lungu D.macovei C.Bartha L.Albulescu C.Tanase S.Nita N.Rusu D.m.Grant J.m.F.Ferreira G.E.Stan National Institute of materials Physics MagureleRO-077125Romania Advanced materials Research Group Faculty of EngineeringUniversity of NottinghamNG72RDUK CICECodAveiro Institute of materials Department of Materials and Ceramics EngineeringUniversity of Aveiro3810-193AveiroPortugal “Victor Babes”National Institute of Research and Development in Pathology and Biomedical Sciences BucharestRO-050096Romania National Institute for Chemical Pharmaceutical Research and Development BucharestRO-031299Romania

The incorporation of therapeutic-capable ions into bioactive glasses(BGs),either based on silica(SBGs)or phosphate(PBGs),is currently envisaged as a proficient path for facilitating bone *** with this view,the single and complementary structural and bio-functional roles of CuO andGa_(2)O_(3)(in the 2e5 mol%range)were assessed,by deriving a series of SBG and PBG formulations startingfrom the parent glass systems,FastOs®BG e 38.5SiO2d36.1Caod5.6P2O5d19.2mgod0.6CaF2,and50.0P2O5d35.0Caod10.0Na_(2)od5.0 Fe2O_(3)(mol%),respectively,using the process of *** inter-linked physico-chemistry e biological response of BGs was assessed in search of bio-functional *** light was shed on the structural role e as network former or modifier e ofCu and Ga,immersed in SBG and PBG *** preliminary biological performance was surveyedin vitro by quantification of Cu and Ga ion release under homeostatic conditions,cytocompatibility assays(in fibroblast cell cultures)and antibacterial tests(against Staphylococcus aureus).The similar(Cu)anddissimilar(Ga)structural roles in the SBG and PBG vitreous networks governed their ***,Cuions were leached in similar concentrations(ranging from 10e35 ppm and 50e110 ppm at BG doses of 5and 50 mg/mL,respectively)for both type of BGs,while the release of Ga ions was 1e2 orders ofmagnitude lower in the case of SBGs(i.e.,0.2e6 ppm)compared to PBGs(i.e.,9e135 ppm).This wasattributed to the network modifier role of Cu in both types of BGs,and conversely,to the network former(SBGs)and network modifier(PBGs)roles of *** glasses were cytocompatible at a dose of 5 mg/mL,while at the same concentration the antimicrobial efficiency was found to be accentuated by the coupledrelease of Cu and Ga ions from *** collective assessment,the most prominent candidate material forthe further development of implant coatings and bone graft substitutes was delineated as the38.5SiO2d34.1Caod5.6P2O5d16.2mgod

关键词： Bioactive glass Copper Gallium Structure Ion release Antibacterial

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Loss of Notch signaling in skeletal stem cells enhances bone formation with aging

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Bone Research 2023年第4期11卷 737-750页

作者： Lindsey h.Remark Kevin Leclerc malissa Ramsukh Ziyan Lin Sooyeon Lee Backialakshmi Dharmalingam Lauren Gillinov Vasudev V.Nayak Paulo El Parente margaux Sambon Pablo J.Atria mohamed A.E.Ali Lukasz Witek Alesha B.Castillo Christopher Y.Park Ralf h.Adams Aristotelis Tsirigos Sophie m.morgani Philipp Leucht Department of Orthopaedic Surgery NYU Robert I.Grossman School of MedicineNew YorkNYUSA Applied Bioinformatics Laboratories NYU Grossman School of MedicineNew YorkNYUSA Institute of Comparative molecular Endocrinology Ulm UniversityUlmGermany max Planck Institute for molecular Biomedicine Department of Tissue Morphogenesisand University of MünsterFaculty of MedicineD-48149 MünsterGermany Department of Biochemistry and molecular Biology University of Miami Miller School of MedicineMiamiFLUSA Department of Pathology NYU Robert I.Grossman School of MedicineNew YorkNYUSA Biomaterials Division New York University College of DentistryNew YorkNYUSA hansjörg Wyss Department of Plastic Surgery NYU Grossman School of MedicineNew York UniversityNew YorkNYUSA Department of Biomedical Engineering Tandon School of EngineeringNew York UniversityBrooklynNYUSA Department of Cell Biology NYU Robert I.Grossman School of MedicineNew YorkNYUSA

Skeletal stem and progenitor cells(SSPCs) perform bone maintenance and repair. With age, they produce fewer osteoblasts and more adipocytes leading to a loss of skeletal integrity. The molecular mechanisms that underlie this detrimental transformation are largely unknown. Single-cell RNA sequencing revealed that Notch signaling becomes elevated in SSPCs during aging. To examine the role of increased Notch activity, we deleted Nicastrin, an essential Notch pathway component, in SSPCs in vivo. middle-aged conditional knockout mice displayed elevated SSPC osteo-lineage gene expression, increased trabecular bone mass, reduced bone marrow adiposity, and enhanced bone repair. Thus, Notch regulates SSPC cell fate decisions, and moderating Notch signaling ameliorates the skeletal aging phenotype, increasing bone mass even beyond that of young mice. Finally, we identified the transcription factor Ebf3 as a downstream mediator of Notch signaling in SSPCs that is dysregulated with aging, highlighting it as a promising therapeutic target to rejuvenate the aged skeleton.

关键词： Notch skeletal elevated

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西德联邦铁路120系列机车辅助传动变流器采用GTO元件关断的逆变器

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国外铁道机车与动车 1985年第1期 48-50页

作者： h.B hm m.Girschikofsky 罗远谋

1.引言安装于西德联邦铁路120系列五台原型机车上的、采用晶体管关断逆变器的辅助传动变流器,在严酷运行条件下经过长期试验,证实其工作可靠,并对该机车在这一期间被证实已经成熟、已可进行批量生产作出了贡献。然而,功率半导体元件领... 详细信息

1.引言安装于西德联邦铁路120系列五台原型机车上的、采用晶体管关断逆变器的辅助传动变流器,在严酷运行条件下经过长期试验,证实其工作可靠,并对该机车在这一期间被证实已经成熟、已可进行批量生产作出了贡献。然而,功率半导体元件领域的发展并未停顿于此,在这一试验过程中,两台机车(120002和120004)的辅助传动变流器已装有新近研制的逆变器,以考核今后推广使用的可能性。其中主可控硅的关断元件采用可关断的可控硅元件,即所谓 GTO 可控硅元件。下面叙述这种有发展前途的技术的作用方式和优点。

关键词：逆变器电子器件可控硅元件晶闸管变流器关断辅助传动联邦铁路西德德国

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COLOR ARRAY IN TFA TEChNOLOGY

COLOR ARRAY IN TFA TECHNOLOGY

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1995 4th International Conference on Solid-State and Integrated Circuit Technology

作者： Q.Zhu T.Lulé h.Stiebig T.martin J.Giehl J.Zhou h.Fischer m.Bhm Universitat-Gh Siegen Institut fur Halbleiterelektronik （IHE） D-57068 Siegen Germany Universitat-Gh Siegen Institut fur Halbleiterelektronik （IHE） D-57068 Siegen Germany Universitat-Gh Siegen Institut fur Halbleiterelektronik （IHE） D-57068 Siegen Germany Universitat-Gh Siegen Institut fur Halbleiterelektronik （IHE） D-57068 Siegen Germany Universitat-Gh Siegen Institut fur Halbleiterelektronik （IHE） D-57068 Siegen Germany Universitat-Gh Siegen Institut fur Halbleiterelektronik （IHE） D-57068 Siegen Germany Universitat-Gh Siegen Institut fur Halbleiterelektronik （IHE） D-57068 Siegen Germany Universitat-Gh Siegen Institut fur Halbleiterelektronik （IHE） D-57068 Siegen Germany

＜正＞ A novel color image sensor array based on TFA （Thin Film on ASIC） technology is described In the array a-Si（C）:h nipin diodes act as optical three color detectors, whereas the crystalline circuit provides photo current integration and signal readout. In this way a single pixel sequentially generates a full color RGB signal without the need of color filters The transient response of the diode under pulsed illumination is examined in order to evaluate the impact of the detector speed on sensor performance and image quality. By proper design of the pixel electronics and technological means the full dynamic range of the color diode can be exploited in the array.

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香烟提取物诱导牛冠状动脉内皮细胞损伤的机制

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环境与健康杂志 2008年第9期25卷 776-778,F0003页

作者：战威 ShEETS Sm WONG L mARTINS-GREEN m CASIANO CA FLETChER hm 天津医科大学公共卫生学院天津300070 美国罗马林达大学医学院微生物学与生物化学系美国加州大学里弗塞德分校细胞生物学与神经生物学系

目的通过观察香烟提取物对牛冠状动脉内皮细胞(BCAEC)的损伤作用,为研究吸烟与心血管疾病之间的关系提供依据。方法以吸烟者体内通常的尼古丁浓度为基准,分别用尼古丁、香烟主流烟雾提取物(mSW)和侧流烟雾提取物(SSW)对 BCAEC 进行染毒... 详细信息

目的通过观察香烟提取物对牛冠状动脉内皮细胞(BCAEC)的损伤作用,为研究吸烟与心血管疾病之间的关系提供依据。方法以吸烟者体内通常的尼古丁浓度为基准,分别用尼古丁、香烟主流烟雾提取物(mSW)和侧流烟雾提取物(SSW)对 BCAEC 进行染毒(尼古丁染毒终浓度分别为1×10^(-5)、0.8×10^(-5)、0.9×10^(-5)mol/L),用显微数码成像系统记录细胞形态变化,检测凋亡细胞与坏死细胞的发生比例,测定 caspase 酶活力。结果经尼古丁、mSW 处理的 BCAEC 形态上发生凋亡样变化,处理24 h 后凋亡细胞发生率为5.89%和11.94%。而 SSW 处理后的 BCAEC 呈坏死样变化.处理24 h 后62.84%的细胞发生坏死。尼古丁和 mSW 可诱导 caspase-3活力增高。结论香烟提取物可诱导牛冠状动脉内皮细胞损伤,mSW 可引起细胞凋亡,SSW 导致细胞坏死,caspase-3的激活可能是香烟提取物诱导牛冠状动脉内皮细胞凋亡的机制。

关键词：烟草烟污染香烟提取物尼古丁牛冠状动脉内皮细胞细胞损伤细胞凋亡细胞坏死

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