检索结果-南通市图书馆

Research in Astronomy and Astrophysics 2018年第8期18卷 29-40页

作者： Sergei v.Antipin Ignacio Becker Alexander A.Belinski Darya M.Kolesnikova Karim Pichara Nikolay N.Samus Kirill v.Sokolovsky alia v.zharova Alexandra M.Zubareva P.K.Sternberg Astronomical Institute M.V.Lomonosov Moscow University13University Ave.Moscow 119234Russia Pontificia Universidad Catolica de Chile SantiagoChile Institute of Astronomy Russian Academy of Sciences48Pyatnitskaya Str.Moscow 109017Russia Institute for Applied Computational Science Harvard UniversityCambridgeMAUSA IAASARS National Observatory of Athens15236 PenteliGreece Astro Space Center of Lebedev Physical Institute Profsoyuznaya Str.84/32Moscow 117997Russia

Using 172 plates taken with the 40-cm astrograph of the Sternberg Astronomical Institute （Lomonosov Moscow University） in 1976-1994 and digitized with a resolution of 2400dpi, we dis- covered and studied 275 new variable stars. We present the list of our new variables with all necessary information concerning their brightness variations. As in our earlier studies, the new discoveries show a rather large number of high-amplitude Delta Scuti variables, predicting that many stars of this type re- main not detected in the whole sky. We also performed automated classification of the newly discovered variable stars based on the Random Forest algorithm. The results of the automated classification were compared to traditional classification and showed that automated classification was possible even with noisy photographic data. However, further improvement of automated techniques is needed, which is especially important when considering the very large numbers of new discoveries expected from all-sky surveys.

关键词： techniques photometric

Amyloid β and free heme：bloody new insights into the pathogenesis of Alzheimer＇s disease

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2018年第7期13卷 1170-1174页

作者： Jorg Flemmig Marcel Zámocky A alia Institute for Medical Physics and Biophysics Medical Faculty Leipzig University Leipzig Germany Institute of Molecular Biology Slovak Academy of Sciences Bratislava Slovakia Institute of Chemical Environmental and Biological Engineering Faculty of Technical Chemistry Vienna University of Technology Vienna Austria Leiden Institute of Chemistry Faculty of Science Leiden University Leiden The Netherlands

The cerebral formation of Amyloid β（Aβ） is a critical pathological feature of Alzheimer＇s disease（AD）.An accumulation of this peptide as senile plaques（SP） was already reported by Alois Alzheimer,the discoverer of the *** the exact contribution of Aβ to AD development remains ***,while extensive cerebral Aβ formation leads to fibril formation in many species,AD-like symptoms apparently depend on the highly conserved N-terminal residues R5,Y10 and *** amino acids were also shown to lead to the formation of Aβ-heme complexes,which exhibit peroxidase activity in the presence of H_2O_*** together these observations we propose that the formation and enzymatic activity of the named complexes may represent an essential aspect of AD ***,Aβ is also known to lead to cerebral micro-vessel destruction（CAA） as well as to hemolytic *** we suggest that the Aβ-derived cerebral accumulation of blood-derived free heme represents a likely precondition for the subsequent formation of Aβ-heme complexes.

关键词： Alzheimer's disease amyloid β sequence amyloid β-heme complexes peroxidase activity dityrosine formation cerebral amyloid angiopathy hemolysis

Modified Alumina Cement with High Service Properties

在线全文

学校读者我要写书评

暂无评论

China's Refractories 2016年第4期25卷 1-5页

作者： Sergey M.LOGvINKOv GalinaN.SHABANOvA alia N.KOROHODSKA Elena v.KHRYSTYCH Kharkov National University of Economic after named of S. Kuznets Kharkov 61166 Ukraine National Technical University “Kharkov Polytechnic Institute” Kharkov 61002 Ukraine National University of Civil Protection of Ukraine Kharkov 61023 Ukraine

This scientific paper gives consideration to the information on the contemporary structure of binary systems and three-component CaO-Al_2O_3-ZrO_2 system required to select rational parameters for the synthesis of cementing *** production process of experimental clinker that has a Ca_7Al_6ZrO_（18） composition has been *** data of X-ray phase analysis and petrographic analysis of the experimental composition of special cement have been given and the reasons for availability of inappropriate phases have been *** processes of hydration hardening of the cement stone have been studied and the data of differential thermal analysis were used for the establishment of the hydration mechanism for basic crystal phases in the cement clinker *** differences in the hydration processes of experimental special cement were analyzed in comparison with known mechanisms.A possibility of the exploitation of special binder in contact with ZrO_2（CaO-stabilized）was tested using the specimens of fine concrete that were subjected to thermal treatment in different *** physical and mechanical properties of specimens and the mineralogical composition of concretes were given based on the data of X-ray analysis and the petrographic *** cement additive was selected and its amount in the concrete composition was defined to slow-down the hardening and the mixture plasticization *** relationships of physical and mechanical characteristics of concrete specimens were defined experimentally as a function of granulometric composition of the filler and thermal treatment *** investigation data of corrosion resistance obtained using the static method were used to find out if experimental concretes can operate in contact with the steel-smelting alkaline slag.

关键词： hydration binder hardening smelting inappropriate Alumina Modified alkaline possibility aggregate

Cytotoxicity and non-specific cellular uptake of bare and surface-modified upconversion nanoparticles in human skin cells

在线全文

学校读者我要写书评

暂无评论

Nano Research 2015年第5期8卷 1546-1562页

作者： Anna E. Guller alia N. Generalova Elena v. Petersen Andrey v. Nechaev Inna A. Trusova Nikolay N. Landyshev Annemarie Nadort Ekaterina A. Grebenik Sergey M. Deyev Anatoly B. Shekhter Andrei v. Zvyagin Macquarie University Australia I.M. Sechenov First Moscow State Medical University Russia Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences Russia Nizhny Novgorod State University Russia Moscow Institute of Physics and Technology Russia Moscow State University of Fine Chemical Technologies Russia University of Amsterdam the Netherlands

The cytotoxicity and non-specific cellular uptake of the most popular composition of upconversion nanoparticle （UCNP）, NaYF4：Yb^3＋：Er^3＋, is reported using normal human skin cells, including dermal fibroblasts and immortalized human epidermal linear keratinocytes （HaCaT）. A new hydrophilization reaction of as-synthesized UCNPs based on tetramethylammonium hydroxide （TMAH） enabled evaluation of the intrinsic cytotoxicity of bare UCNPs. The cytotoxicity effects of the UCNP surface-coating and polystyrene host were investigated over the concentration range 62.5-125 μg/mL with 24-h incubation, using a MTT test and optical microscopy. The fibroblast viability was not compromised by UCNPs, whereas the viability of keratinocytes varied from 52% ± 4% to 100% ± 10% than the control group, depending on the surface modification. Bare UCNPs reduced the keratinocyte viability to 76% ± 3%, while exhibiting profound non-specific cellular uptake. Hydrophilic poly（D,L-lactide）- and poly（maleic anhydride-alt-l-octadecene）-coated UCNPs were found to be least cytotoxic among the polymer-coated UCNPs, and were readily internalized by human skin cells. Polystyrene microbeads impregnated with UCNPs remained nontoxic. Surprisingly, no correlation was found between UCNP cytotoxicity and the internalization level in cells, although the latter ranged broadly from 0.03% to 59%, benchmarked against 100% uptake level of TMAH-UCNPs.

关键词： nanoparticle upconversion surface modification biocompatibility cytotoxicity human skin

The role of vISTA in the tumor microenvironment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Cancer Metastasis and Treatment 2022年第1期8卷 365-378页

作者： Dina Rabadi alia A.Sajani Randolph J.Noelle J.Louise Lines Department of Biological Sciences Dartmouth CollegeHanoverNH 03755USA Department of Microbiology and Immunology Norris Cotton Cancer CenterGeisel School of Medicine at DartmouthLebanonNH 03756USA

v-domain Ig Suppressor of T cell Activation(vISTA)is a negative immune checkpoint that is expressed on multiple immune cell subsets and has been characterized in T cells,macrophages,and myeloid-derived suppressor *** the only immune checkpoint expressed on naïve T cells,vISTA contributes to the maintenance of T cell quiescence and *** also regulates multiple myeloid cell activities such as chemotaxis,differentiation,and *** the context of cancer,antagonistic monoclonal antibody targeting of vISTA has been shown to aid anti-tumor ***,combination therapies that include other immune checkpoints such as PD-1 or CTLA-4 with vISTA blockade may enhance therapeutic efficacy in a variety of *** therapy may help overcome adaptive resistance to individual checkpoint therapies,thereby improving patient outcomes and ***,we summarize the role of vISTA in myeloid cells and T cells within the tumor *** discuss the proposed counter-receptors for vISTA,vISTA antibodies currently in development,and the potential for combination therapies with checkpoint inhibitors such as PD-1 and CTLA-4.

关键词： vISTA cancer MDSC immune checkpoint

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

煤中痕量元素分布的多变量分析及实验研究

环境化学 1995年第6期14卷 494-499页

作者：陆晓华 alia 刘汉珍曾汉才华中理工大学化学系武汉430074 华中理工大学媒燃烧国家重点实验室

本文用多变量分析法研究了煤中痕量元素的分布,并用实验研究了有机溶剂提取前后青山烟煤中痕量元素的变化.多变量分析结果表明:As,***,Ni,Cu,Cd,v,Pb等元素与Be,Ge在煤中具有不同的分布特征.对青山烟煤的实验研究结果则表明:Cr,Co,Ni,Cu... 详细信息

本文用多变量分析法研究了煤中痕量元素的分布,并用实验研究了有机溶剂提取前后青山烟煤中痕量元素的变化.多变量分析结果表明:As,***,Ni,Cu,Cd,v,Pb等元素与Be,Ge在煤中具有不同的分布特征.对青山烟煤的实验研究结果则表明:Cr,Co,Ni,Cu,Cd,Pb等元素趋向于与煤中的矿物质相结合,而Be,Ge两元素有较强的有机亲和性.实验研究结果与多变量分析结果相符.

关键词：煤痕量元素多变量分析燃烧环境化学

Low Temperature Transport Properties of Multigraphene Structures on 6H-SiC Obtained by Thermal Graphitization： Evidences of a Presence of Nearly Perfect Graphene Layer

在线全文

学校读者我要写书评

暂无评论

材料科学与工程（中英文A版） 2013年第11期3卷 757-762页

作者： Alexander A. Lebedev Nina v. Agrinskaya vyacheslav A. Beresovets veniamin I. Kozub Sergei P.Lebedev alia A. Sitnikova A. F. loffe Institute Russian Academy of Sciences Saint Petersburg 194021 Russia National Research University of Information Technologies Mechanics and Optics Saint-Petersburg 197101 Russia International Laboratory of High Magnetic Fields and Low Temperatures Wroclaw 53421 Poland

Transport properties of multigraphene layers on 6H-SiC substrates fabricated by thermal graphitization of SiC were studied. The principal result is that these structures were shown to contain a nearly perfect graphene layer situated between the SiC substrate and multgraphene layer. It was found that the curves of magnetoresistance and Shubnikov- de Haas oscillations shown the features, typical for single-layered graphene. The low temperature resistance demonstrated an increase with temperature increase, which also corresponds to a behavior typical for single-layered graphene (antilocalization). However, at higher temperatures the resistance decreased with an increase of temperature, which corresponds to a weak localization. We believe that the observed behavior can be explained by a parallel combination of contributions to the conductivity of single-layered graphene and of multigraphene, the latter allowing to escape damages of the the graphene by atmosphere effect.

关键词： 6H-SiC 石墨化耐低温输运性质结构证据高温度传输性能

Chronic ischemic mitral valve regurgitation and surgical perspectives

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Cardiology 2018年第10期10卷 141-144页

作者： Salah Eldien Altarabsheh Salil v Deo Abeer Rababa'h Yagthan M Obeidat Osama Haddad Division of Cardiovascular Surgery Queen Alia Heart Institute Division of Cardiovascular Surgery Harrington Heart and Vascular InstituteCase Western Reserve University Department of Clinical Pharmacy Jordan University of Science and Technology Department of Cardiac Surgery AlMana General Hospital Department of Thoracic and Cardiovascular Surgery Cleveland Clinic

Chronic ischemic mitral valve regurgitation is a result of disturbed left ventricular geometry secondary to myocardial ischemia in the absence of intrinsic mitral valve pathology. It is a common complication after myocardial infarction, and patients who have ischemic mitral regurgitation(IMR) have a worse prognosis compared to patients who have ischemic heart disease alone, and this is directly related to the severity of IMR. Medical therapy has limited efficacy, and surgical options including various repair techniques and valve replacement had been tried with variable success. Still there is intense debate among surgeons whether to interfere with moderate degree IMR at the time of coronary artery revascularization.

关键词： Mitral regurgitation Myocardial infarction Ring annuloplasty valve replacement

Binary vector Construction for Site-Directed Mutagenesis of <i>Kafirin</i>Genes in Sorghum

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Plant Sciences 2021年第8期12卷 1276-1287页

作者： Grigoriy A. Gerashchenkov Lev A. Elkonin Kirill G. Gerashchenkov Natalia A. Rozhnova Stefan Hiekel Jochen Kumlehn Alexey v. Chemeris Institute of Biochemistry and Genetics Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences Ufa Russia Federal Centre of Agriculture Research of South-East Region Saratov Russia Kazan Federal University Institute of Fundamental Medicine and Biology Kazan Russia Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben Germany

Sorghum (Sorghum bicolor (L.) Moench) is one of the world’s leading cereal crops in agricultural production, which has a special importance in the arid regions. However, unlike other cereals, sorghum grain has a lower nutritional value, which is caused, inter alia, by the resistance of its seed storage proteins (kafirins) to protease digestion. One of the effective approaches to improve the nutritional value of sorghum grain is to obtain mutants with partially or completely suppressed synthesis or altered amino acid composition of kafirins. The employment of genome editing may allow to solve this problem by introducing mutations into the nucleotide sequences of the α- and γ-kafirin genes. In this study, genomic target motifs (23 bp sequences) were selected for the introduction of mutations into the α- and γ-KAFIRIN genes of sorghum. The design of the gRNAs was conducted using the online tools CRISPROR and CHOPCHOP. Two most suitable targets were chosen for α-KAFIRIN (k1C5) and two for γ-KAFIRIN (gKAF1) genes. The insertion of respective sequences in the generic vector pSH121 was performed at the BsaI (Eco31I) sites. validation of the cloning procedure was performed by DNA sequencing. Subcloning of the resulting constructs was performed using the SfiI restriction sites into the compatible binary vector B479p7oUZm-LH. The correct assembly of binary vectors was confirmed by restriction analysis using the MluI and SfiI cleavage sites. The four vectors created (1C - 4C) were transferred by electroporation into the Agrobacterium tumefaciens strain AGL0. Currently, this vector series is used for stable

关键词： Sorghum bicolor (L.) Moench CRISPR/Cas Genome Editing α-Kafirin γ-Kafirin Genetic Engineering Grain Quality