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characterization of the High-Strength Mg–3Nd–0.5Zn Alloy Prepared by Thermomechanical Processing

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Acta Metallurgica Sinica(English Letters) 2019年第3期32卷 321-331页

作者： Ji■í Kub■sek drahomír dvorsk■ Jozef Vesel■ Peter Min■rik M■ria Zemkov■ dalibor Vojtěch department of Metals and Corrosion Engineering Faculty of Chemical Technology University of Chemistry and Technology Prague department of Physics of Materials Charles University

Magnesium alloys based on Nd and Zn are promising materials for both aviation industry and medical *** mechanical properties of these materials can be achieved by thermomechanical processing such as extrusion or rolling and by aging treatment, which can significantly strengthen the alloy. The question remains especially about the connection of texture strength created in the alloys based on the specific conditions of preparation. This work focuses on the Mg–3 Nd–0.5 Zn magnesium alloy prepared by hot extrusion of the as-cast state at two different temperatures combined with heat pre-treatment. Extrusion ratio of 16 and rate of 0.2 mm/s at 350 and 400 °C were selected for material preparation. The structures of prepared materials were studied by scanning electron microscopy and transmission electron microscopy. The effect of microstructure on mechanical properties was evaluated. Obtained results revealed the strong effect of thermal pre-treatment on final microstructure and mechanical properties of extruded materials. The Hall–Petch relation between grain size and tensile yield strength has been suggested in this paper based on the literature review and presented data. The observed behavior strongly supports the fact that the Hall–Petch of extruded Mg–3Nd–0.5 Zn alloys with different texture intensities cannot be clearly estimated and predicted. In addition, Hall–Petch relations presented in literature can be sufficiently obtained only for fraction of the Mg–3Nd–0.5 Zn alloys.

关键词： Mg–Nd–Zn alloys Extrusion Thermal treatment Microstructure Mechanical properties

ISSR markers based on ga and AG repeats reveal genetic relationship among rice varieties tolerant to drought,flood,or salinity

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第2期10卷 133-141页

作者： ch Surendhar REddY A. Prasad BABU B.P. Mallikarjuna SWAMY K. KALAdHAR N. SARLA Biotechnology Laboratory Crop Improvement SectionDirectorate of Rice ResearchRajendranagar

drought, flood, salinity, or a combination of these limits rice production. Several rice varieties are well known for their tolerance to specific abiotic stresses. We determined genetic relationship among 12 rice varieties including 9 tolerant to drought, flood, or salinity using inter-simple sequence repeat （ISSR） markers. Based on all markers, the nine tolerant varieties formed one cluster distinct from the cluster of three control varieties. The salt-tolerant varieties were closest to two flood-tolerant varieties, and together they were distinct from the drought-tolerant varieties. （ga）8YG was the most informative primer, showing the highest polymorphic information content （PIC） and resolving power （Rp）. The drought-, flood-, and salt-tolerant varieties grouped in three distinct clusters within the group of tolerant varieties, when （ga）8YG was used. Sabita was the only exception. The two aus varieties, Nagina22 and FR13A, were separated and grouped with the drought- and flood-tolerant varieties, respectively, hut they were together in dendrograms based on other primers. The results show that ISSR markers associated with （ga）sYG delineated the three groups of stress-tolerant varieties from each other and can be used to identify genes/new alleles associated with the three abiotic stresses in rice germplasm.

关键词： drought Submergence Salinity Inter-simple sequence repeat-polymerase chain reaction (ISSR-PCR) (ga)8YG Nagina22 (N22) FR13A Pokkali

Antioxidant and Antiplasmodial Activities of Extracts from <i>gardenia erubescens</i>Stapf et Hutch. and <i>Fadogia agrestis</i>Schweinf. ex Hiern. (Rubiaceae)

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Open Journal of Applied Sciences 2020年第11期10卷 675-687页

作者： Mariama Kaba Combasséré-chérif Hadidjatou Belem Benjamin Koama Assetou Sawadogo Sandrine Nadège da Windmi Kagambéga Anne-Flora drabo Roland Nâg-Tiéro Meda George Anicet Ouédraogo Laboratory for Research and education in Animal Health and Biotechnologies Nazi Boni University Bobo-Dioulasso Burkina Faso Health Action Research Group Ouagadougou Burkina Faso Laboratory of Pharmacology Research Institute in Health Sciences Bobo-Dioulasso Burkina Faso

Two medicinal plants, gardenia erubescens and Fadogia agrestis were selected to evaluate their biological activities. Their total phenolic and flavonoid contents were assessed using folin-ciocalteu and aluminum chlori... 详细信息

Two medicinal plants, Gardenia erubescens and Fadogia agrestis were selected to evaluate their biological activities. Their total phenolic and flavonoid contents were assessed using folin-ciocalteu and aluminum chloride regents’ methods. The antioxidant activity was estimated using DPPH (1,1-diphényl-2-picrylhydrazyl), ABTS (2,2’-azinobis-[3-ethylenzothiazoline-6-sulfonic acid]) and FRAP (ferric reducing antioxidant power). The antiplasmodial activity of the extracts was determined in vivo on 42 NMRI mice. The results indicate that all the extracts from both two plants contain some polyphenols. The ethanolic extract of the leaves of Gardenia erubescens showed the best antioxidant activity by the method of DPPH. The aqueous extracts of the leaves of Gardenia erubescens and the whole plant of Fadogia agrestisdana;

关键词： Antiplasmodial Activity Antioxidant Activity gardenia erubescens Fadogia agrestis

Predicted Modulated differential Rates for direct WIMP Searches at Low Energy Transfers

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Communications in Theoretical Physics 2012年第3期57卷 504-514页

作者： J.d.Vergados CERN Theory DivisionCH 1211Geneva 23Switzerland Kavli Institute for Theoretical Physics china (KITPC) Institute of Theoretical PhysicsChinese Academy of Science

The differential event rate for direct detection of dark matter,both the time averaged and the modulated one due to the motion of the Earth,are *** calculations focus on relatively light cold dark matter candidates (WIMP) and low energy *** is shown that for sufficiently light WIMPs the extraction of relatively large nucleon cross sections is *** for some WIMP masses the modulation amplitude may change sign,meaning that,in such a case,the maximum rate may occur six months later than naively *** effect can be exploited to yield information about the mass of the dark matter candidate,if and when the observation of the modulation of the event rate is established.

关键词： dark matter WIMP direct detection WIMP-nucleus scattering event rates modulation

direct Comparison of Catalyst-Free and Catalyst-Induced gaN Nanowires

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Nano Research 2010年第7期3卷 528-536页

作者： Caroline chèze Lutz Geelhaar Oliver Brandt Walter M.Weber Henning Riechert Steffen Münch Ralph Rothemund Stephan Reitzenstein Alfred Forchel Thomas Kehagias Philomela Komninou George P.dimitrakopulos Theodoros Karakostas Paul-drude-Institut für Festkörperelektronik 5-7 HausvogteiplatzBerlin 10117Germany NaMLab gGmbH Dresden 01187Germany Technische Physik Universität WürzburgAm HublandWürzburg 97074Germany Physics department Aristotle UniversityThessaloniki 54124Greece

gaN nanowires have been grown by molecular beam epitaxy either catalyst-free or catalyst-induced by means of Ni *** identical growth conditions of temperature andⅤ/Ⅲratio,both types of gaN nanowires are of wurtzite structure elongated in the ga-polar direction and are constricted by M-plane ***,the catalyst-induced nanowires contain many more basal-plane stacking faults and their photoluminescence is *** differences can be explained as effects of the catalyst Ni seeds.

关键词： Nanowire nanocolumn molecular beam epitaxy(MBE) photoluminescence stacking faults catalyst

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转染癌基因的骨髓基质干细胞体外分化特征

中国组织工程研究与临床康复 2007年第3期11卷 459-462,466,I0002页

作者：张刚庆方驰华高鹏郑权颜政向国安陈规划中山大学博士后科研基地广东省广州市510317 南方医科大学附属珠江医院肝胆外科广东省广州市510282 广东省第二人民医院普外科广东省广州市510317 中山大学附属第三临床医学院器官移植科广东省广州市510000

目的:观察转染癌基因的骨髓基质干细胞在体外分化情况,为肝细胞癌的细胞源研究提供实验依据。方法:实验于2003-05/2004-06在南方医科大学药理教研室实验室完成。①两步法获取大鼠肝细胞,梯度离心法分离大鼠骨髓基质干细胞。②单基因转... 详细信息

目的:观察转染癌基因的骨髓基质干细胞在体外分化情况,为肝细胞癌的细胞源研究提供实验依据。方法:实验于2003-05/2004-06在南方医科大学药理教研室实验室完成。①两步法获取大鼠肝细胞,梯度离心法分离大鼠骨髓基质干细胞。②单基因转染是单独将c-myc或K-ras癌基因瞬时转染大鼠骨髓基质干细胞,6孔培养板中培养,24h后荧光显微镜下观察骨髓基质干细胞转染结果。双基因转染步骤相同,只是将c-myc和K-ras癌基因同时转染大鼠骨髓基质干细胞。③c-myc癌基因转染组、K-ras癌基因转染组、双癌基因转染组常规培养,加入含体积分数为0.1胎牛血清的dMEM培养基,于37℃、体积分数为0.05的CO2孵箱培养,每24h半量更换培养液。④c-myc癌基因转染+肝细胞组、K-ras癌基因转染+肝细胞组、双癌基因转染+肝细胞组将已转染癌基因的骨髓基质干细胞,置于叠加的培养板半透膜的上方(细胞密度均为1×105个/cm2),再将肝细胞置于半透膜的下方(每孔细胞密度为3×105/cm2)进行共培养,其余步骤同常规培养。⑤通过反转录聚合酶式反应和细胞免疫组化检测骨髓基质干细胞分化情况。结果:①癌基因转染24h骨髓基质干细胞检测结果:单独转染c-myc或K-ras癌基因的细胞,其绿色荧光蛋白呈均匀一致分布;双基因转染的细胞,绿色荧光蛋白呈点片状分布。②各组骨髓基质干细胞向肿瘤细胞分化检测结果:c-myc癌基因转染组、K-ras癌基因转染组、双癌基因转染组的骨髓基质干细胞,均未向肿瘤细胞分化;c-myc癌基因转染+肝细胞组、K-ras癌基因转染+肝细胞组、双癌基因转染+肝细胞组的骨髓基质干细胞,均向肝细胞癌发展;空白对照组骨髓基质干细胞细胞均为阴性。此外,双癌基因转染+肝细胞组的骨髓基质干细胞分化增殖迅速,反转录聚合酶式反应和免疫组化检测发现,培养第7天出现甲胎蛋白表达,并迅速增加,而第7天出现的白蛋白和细胞角蛋白18表达迅速减弱,第14天消失。结论:转染癌基因的骨髓基质干细胞,在向肝细胞诱导的条件下,部分癌基因可以使干细胞分化为肝癌细胞;多癌基因转染时,更易于使干细胞分化为肝癌细胞。

关键词：骨髓细胞造血干细胞癌基因

Study of the Activation Process of a 2 m3 Pilot Biodigester on a Microfarm Site

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Journal of Agricultural chemistry and Environment 2023年第4期12卷 397-413页

作者： Jean-Baptiste Mansaly djicknoum diouf Bruno Pirou Elhadji Mba Bamdo diakhaby Seynabou Lo Amadou Seidou Maïga diène Ndiaye Laboratoire Environnement Ingénierie Télécommunications et Energies Renouvelables Université Gaston Berger de Saint-Louis Saint-Louis Sénégal Centre de coopération Internationale en Recherche Agronomique pour le développement Montpellier France Laboratoire Régional de Saint Louis et UFR-2S Université Gaston Berger Saint Louis Sénégal

A domestic balloon-type digester with 1200 liters of substrate and a 700-litre gas reserve was installed at the Université gaston Berger pilot farm, which has 4 cows. After an initial load of 1000 L of water, 90 L of bovine rumen and 145 L of cow dung, the functional parameters of the reaction medium, i.e., temperature, pH, salinity and conductimetry, were regularly monitored at a rate of 3 tests per day until the thirtieth day, corresponding to the flame test and the start of analysis and daily loading of the biodigester. The analysis of the biogas obtained after the flame test showed us the considerable contribution of bovine hindquarters to the ch4 fraction, which reached 72.2% from the start of the production phase. As anaerobic digestion is both a complex and multiparametric process, microbiological analysis revealed the presence of several strains of bacteria in the substrate used. Among the most abundant were Escherichia coli, Klebsiella spp, non-fermentative Gram-negative bacilli and Enterococcus sp. However, the bacterial strain that interests us most in anaerobic digestion is the non-fermentative Gram-negative family. We see the identification and temporal monitoring of these families of bacteria as a major step forward in the control of anaerobic fermentation processes in the Sahelian context and in Senegal in particular.

关键词： Pilot digester Activation Bovine Belly Conductimetry Salinity Microbiology Analysis

Stem cells therapy for regenerative medicine:Principles of present and future practice

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Journal of Biomedical Science and Engineering 2014年第2期7卷 49-57页

作者： Jose A.Andrades Jose Becerra Ramon Munoz-chápuli Salvador Martínez Angel Raya Javier garcía-Sancho Jose M.Moraleda Laboratory of Bioengineering and Tissue Regeneration(LABRET) Department of Cell BiologyGenetics and PhysiologyFaculty of SciencesIBIMAUniversity of MálagaMálagaSpain Networking Biomedical Research Center in Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)MálagaSpain Andalusian Centre for Biotechnology and Nanomedicine(BIONANd) Parque Tecnológico de AndalucíaCampanillasMálagaSpain department of Animal Biology Faculty of SciencesUniversity of MálagaMálagaSpain Institute of Neurosciences University of Miguel HernándezAlicanteSpain Control of Stem Cell Potency Group Institut for Bioengineering of Catalonia(IBEC)BarcelonaSpain Institucio Catalana de Recerca i Estudis Avancats(ICREA) P.Lluís CompanysBarcelonaSpain Institute of Molecular Biology and Genetics(IBGM) University of ValladolidValladolidSpain Unit of Transplant and Cell Therapy University of MurciaIMIBUniversity Clinic Hospital Virgen de la ArrixacaEl PalmarMurciaSpain

The characterization and isolation of various stem cell populations, from embryonic to tissue-derived stem cells and induced pluripotent stem cells (iPSCs), have led to a rapid growth in the field of stem cell research and its potentially clinical application in the field of regenerative medicine and tissue repair. Stem cell therapy has recently progressed from the preclinical to the early clinical trial arena for a variety of diseases states, although further knowledge on action mechanisms, long-term safety issues, and standardization and characterization of the therapeutic cell products remains to be thoroughly elucidated. In this paper we summarize the current state of the art of basic and clinical research that were highlighted at the 2012 meeting of the Spanish Cell Therapy Network. This includes the current research involving in genomic and transcriptomic characterization of selected stem cell populations, studies of the role of resident and transplanted stem cells during tissue regeneration and their mechanism of action, improved new strategies of tissue engineering, transplantation of mesenchymal stem cells (MSCs) in different animal models of disease, disease correction by iPSCs, and preliminary results of cell therapy in human clinical trials.

关键词： Spanish Cell Therapy Network Stem Cell Cell Therapy Tissue Engineering Regenerative Medicine

SARS-CoV-2 interaction with Siglec-1 mediates trans-infection by dendritic cells

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Cellular & Molecular Immunology 2021年第12期18卷 2676-2678页

作者： daniel Perez-Zsolt Jordana Muñoz-Basagoiti Jordi Rodon Marc Elosua-Bayes dàlia Raïch-Regué Cristina Risco Martin Sachse Maria Pino Sanjeev Gumber Mirko Paiardini Jakub chojnacki Itziar Erkizia Xabier Muñiz-Trabudua Ester Ballana Eva Riveira-Muñoz Marc Noguera-Julian Roger Paredes Benjamin Trinité Ferran Tarrés-Freixas Ignacio Blanco Victor Guallar Jorge Carrillo JuliàBlanco Amalio Telenti Holger Heyn Joaquim Segalés Bonaventura Clotet Javier Martinez-Picado Júlia Vergara-Alert Nuria Izquierdo-Useros IrsiCaixa AIdS Research Institute 089BadalonaSpain IRTA Centre de Recerca en Sanitat Animal(CReSAIRTA-UAB)Campus de la UAB08193Bellaterra(Cerdanyola del Vallès)Spain CNAG-CRG Centre for Genomic Regulation(CRGBarcelona Institute of Science and Technology(BIST)08028BarcelonaSpain Centro Nacional de Biotecnología CSIC28049MadridSpain division of Microbiology and Immunology Yerkes National Primate Research CenterEmory UniversityAtlantaGAUSA department of Pathology and Laboratory Medicine School of MedicineEmory UniversityAtlantaGeorgiaUSA division of Pathology Yerkes National Primate Research CenterEmory UniversityAtlantaGeorgiaUSA Germans Trias i Pujol Research Institute(IGTP) Can Ruti Campus089BadalonaSpain Barcelona Supercomputing Center(BSC) 08034BarcelonaSpain Catalan Institution for Research and Advanced Studies(ICREA) 08010BarcelonaSpain University of Vic-Central University of Catalonia(UVic-UCC) Vic08500Spain department of Integrative Structural and Computational Biology Scripps ResearchLa JollaCA92037USA Universitat Pompeu Fabra(UPF) BarcelonaSpain UAB CReSA(IRTA-UAB)Campus de la UAB08193Bellaterra(Cerdanyola del Vallès)Spain departament de Sanitat i Anatomia Animals Facultat de VeterinàriaUAB08193Bellaterra(Cerdanyola del Vallès)Spain

Antigen-presenting cells(APCs)may be resistant to SARS-CoV-2 infection but still contribute to viral *** such as sialic acid-binding Ig-like lectin 1(Siglec-1/Cd169)mediate the attachment of viruses to ***,we show that APCs effectively capture SARS-CoV-2 within compartments via recognition of *** receptor interacts with sialylated gangliosides on membranes of SARS-CoV-2 variants.

关键词： infection Antigen media