检索结果-南通市图书馆

Coherent spin transport through helical edge states of topological insulator

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2020年第1期6卷 224-233页

作者： R.A.Niyazov D.N.Aristov V.Yu.Kachorovskii Ioffe Institute 194021 St.PetersburgRussia Department of Physics St.Petersburg State UniversitySt.Petersburg 198504Russia NRC‘Kurchatov Institute’ Petersburg Nuclear Physics InstituteGatchina 188300Russia CENTERA Laboratories Institute of High Pressure PhysicsPolish Academy of Sciences01-142 WarsawPoland

We study coherent spin transport through helical edge states of topological insulator tunnel-coupled to metallic *** demonstrate that unpolarized incoming electron beam acquires finite polarization after transmission through such a setup provided that edges contain at least one magnetic *** finite polarization appears even in the fully classical regime and is therefore robust to *** is also a quantum magnetic field-tunable contribution to the polarization,which shows sharp identical Aharonov-Bohm resonances as a function of magnetic flux—with the period hc/2e—and survives at relatively high *** demonstrate that this tunneling interferometer can be described in terms of ensemble of flux-tunable qubits giving equal contributions to conductance and spin *** number of active qubits participating in the charge and spin transport is given by the ratio of the temperature and the level *** interferometer can effectively operate at high temperature and can be used for quantum *** particular,the ensemble of qubits can be described by a single Hadamard *** obtained results open wide avenue for applications in the area of quantum computing.

关键词： temperature topological quantum

Effect of Crystallization Conditions on Polymorphic Diversity of Malic Acid Rs-Racemate

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Tianjin University 2013年第2期19卷 86-91页

作者： Isakov A I Kotelnikova E N Kryuchkova L Yu Lorenz H st.petersburg state University St.Petersburg 199034Russia Max Planck Institute for Dynamics of Complex Technical systems Magdeburg 39106Germany

Enantiomers （R （＋） and s（-））, Rs-racemate mixture of enantiomers） of malic acid C4H605 have been （double compound） and （R ＋ s） -conglomerate （mechanical investigated by means of X-ray diffractometry and high tern- perature X-ray diffraction method. The Rs-racemate was found to be able to form three polymorphic modifications, which we denominated as M1 （monoclinic, space group P21/c）, M2 （monoclinic, space group Cc）, and Tc （triclinic, space group P-l ）, the latter modification having been unknown before. Modification Tc was also described, and its X- ray diffraction characteristics, including interplanar spacings d, hkl indices, unit cell parameters, were defined. In addi- tion, X-ray diffraction characteristics for both reported earlier M1 and M2 monoclinic polymorphic modifications were measured with higher accuracy. The ability of Rs-racemate to form one of the above three modifications （MI, M2, and Tc） or their mixtures containing various proportions and combinations of the components （M1 ＋ M2, M1 ＋ Tc, or M2 ＋ Tc） was found to depend on the type of crystallization medium （a melt, aqueous medium, ethanol or acetone solu- tion）, crystallization rate （from 2--3 minutes to 4 months）, and crystallization temperature. Heating s-enantiomer and M1 Rs-racemate up to their respective melting points （100 ℃ and 124 ℃, correspondingly） only made them undergo thermal deformations, while heating （R ＋ s） -conglomerate in the temperature range of 96--110 ℃ resulted in its homogenization to form M2 Rs-racemate, which, near the melting point （118 ℃）, namely, in the range of 112-116 ℃, was transformed into MI Rs-racemate. Keywords： polvmorDhism; racemic, chiral

关键词： polymorphism racemic chiral

Topological Data Analysis of Potentiometric Multisensor Measurements in Treated Wastewater

在线全文

学校读者我要写书评

暂无评论

Journal of Analysis and Testing 2018年第4期2卷 291-298页

作者： Valeria Belikova Vitaly Panchuk Evgeny Legin Anastasia Melenteva Andrey Legin Dmitry Kirsanov Laboratory of Multivariate Analysis and Global Modeling Samara State Technical UniversitySamaraRussia Institute of Chemistry St.Petersburg State UniversitySt.PetersburgRussia Laboratory of Artificial sensory systems ITMO UniversitySt.PetersburgRussia

In this study,a multisensor system consisting of 23 potentiometric sensors was applied for long-term online measurements in outlet flow of the water treatment *** 1 month of continuous measurements,the data set of more than 295,000 observations was *** processing of this dataset with conventional chemometric tools was cumbersome and not very *** data analysis(TDA)was recently suggested in chemometric literature to deal with large spectroscopic *** this research,we explore the opportunities of TDA with respect to multisensor data with only 23 *** is shown that TDA allows for convenient data visualization,studying the evolution of water quality during the measurements and tracking the periodical structure in the data related to the water quality depending on the time of the day and the day of the *** appears to be a valuable tool for multisensor data exploration.

关键词： Topological data analysis Multisensor systems Potentiometric sensors Water quality

Zircon Xenocrysts from the shaka Ridge Record Ancient Continental Crust:New U-Pb Geochronological and Oxygen Isotopic Data

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 Earth science 2022年第1期33卷 5-16页

作者： sergey G.skublov Natalia A.Rumyantseva Qiuli Li Boris G.Vanshtein Dmitriy I.Rezvukhin Xianhua Li Institute of Precambrian Geology and Geochronology of Russian Academy of sciences St.Petersburg 199034Russia saint petersburg Mining University St.Petersburg 199106Russia Institute for Geology and Mineral Resources of the World Ocean(VNIIOkeangeologia) St.Petersburg 190121Russia state Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China sobolev Institute of Geology and Mineralogy Siberian Branch of the Russian Academy of SciencesNovosibirsk 630090Russia

Over the past two decades, a significant number of discoveries of ancient zircon xenocrysts in ocean-floor magmatic rocks have been reported. These findings provide compelling evidence for the presence of ancient continental crust within young oceanic lithosphere. Almost all finds of ancient zircon xenocrysts within oceanic crust are from the Mid-Atlantic Ridge. For other localities, however, similar data are very limited. This report presents the first age determinations(U-Pb, sHRIMPII) and isotope-geochemical data(oxygen, trace and rare earth elements) for zircon xenocrysts from gabbro-diorites of the shaka Ridge, in the vicinity of the shaka fracture zone, near the western end of the southwest Indian Ridge. The work is based on a study of bottom rock material dredged during expeditionary research on the R/V"Akademik Fedorov"(Russia) in 2016. The U-Pb isotope system of the zircon xenocrysts recorded a crystallization age of ~2.8 Ga at an upper discordia intercept and an age of ~600 Ma interpreted as the timing of a superimposed thermal event at a lower discordia *** zircon xenocrysts show geochemical signatures of magmatic origin, i.e., fractionated REE distribution spectra with an increase in chondrite-normalized values from light to heavy REE, positive Ce anomalies and negative Eu anomalies, and high Th/U ratios(0.59-7.77). In discrimination diagrams based on a series of inter-element relationships, zircon compositions fall into the fields of zircons from rocks of continental crust, mostly granitoids. The Li content of the zircons is high(1.8 ppm-50 ppm),adding further evidence to their derivation from rocks of continental crust. During their residence within young oceanic crust, the zircon xenocrysts experienced alterations under the influence of submarine high-temperature hydrothermal fluids, which selectively affected the distribution of trace elements in the zircons and reduced the δ;O values to 1.75‰-3.15‰. The presence of obviously older zircons

关键词： zircon U-Pb geochronology oxygen isotopes trace elements rare earth elements shaka Ridge south Atlantic southwest Indian Ridge

同方期刊数据库

Quantum-dot microlasers based on whispering gallery mode resonators

在线全文

学校读者我要写书评

暂无评论

Light(science & Applications) 2021年第5期10卷 785-795页

作者： A.E.Zhukov N.V.Kryzhanovskaya E.l.Moiseev M.V.Maximov Laboratory of quantum optoelectronics National Research University Higher School of EconomicsKantemirovskaya 3ASt.Petersburg 194100Russia Nanophotonics laboratory Alferov UniversityKhlopina 8/3St.Petersburg 194021Russia

The subject of this paper is microlasers with the emission spectra determined by the whispering gallery *** to the total internal reflection of light on the sidewalls,a high Q-factor is achieved until the diameter is comparable to the *** light emission predominantly occurs in the plane of the structure,which facilitates the microlaser integration with other *** focus on microdisk lasers with various types of the In(Ga)As quantum dots(QDs).Deep localization of charge carriers in spatilly separated regions suppresses the lateral diffusion and makes it possible to overcome the undesirable effect of non-adiative recombination in deep ***,using conventional epitaxial structures and relatively simple post-growth processing methods,it is possible to realize small microlasers capable of operating without temperature stabilization at elevated *** low sensitivity of QDs to epitaxial and manufacturing defects allows fabricating microlasers using IIV heterostructures grown on silicon.

关键词： Quantum mode overcome

GFAP expression in the optic nerve and increased Н2s generation in the integration centers of the rainbow trout（Oncorhynchus mykiss） brain after unilateral eye injury

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2020年第10期15卷 1867-1886页

作者： Evgeniya V.Pushchina Anatoly A.Varaksin Dmitry K.Obukhov Igor M.Prudnikov A.V.Zhirmunsky National scientific Center of Marine Biology Far Eastern BranchRussian Academy of SciencesVladivostokRussia A.A.Bogomoletz Institute of Physiology National Academy of Sciences of UkraineKievUkraine st.petersburg state University St.PetersburgRussia

Hydrogen sulfide(H2s)is considered as a protective factor against cardiovascular ***,there are few reports on the effects of H2s in the central nervous system during stress or *** studies on goldfish have shown that astrocytic response occurs in the damaged and contralateral optic *** fibrillary acidic protein(GFAP)concentration in the optic nerves of rainbow trout has not been measured *** study further characterized the astrocytic response in the optic nerve and the brain of a rainbow trout(Oncorhynchus mykiss)after unilateral eye injury and estimated the amount of H2s-producing enzyme cystathionineβ-synthase(CBs)in the brain of the rainbow *** 1 week after unilateral eye injury,a protein band corresponding to a molecular weight of 50 kDa was identified in the ipsi-and contralateral optic nerves of the rainbow *** concentration of GFAP in the injured optic nerve increased compared to the protein concentration on the contralateral *** results of a quantitative analysis of GFAP+cell distribution in the contralateral optic nerve showed the largest number of GFAP+cells and fibers in the optic nerve *** the damaged optic nerve,patterns of GFAP+cell migration and large GFAP+bipolar activated astrocytes were detected at 1 week after unilateral eye *** study of H2s-producing system after unilateral eye injury in the rainbow trout was conducted using enzyme-linked immunosorbent assay,western blot analysis,and immunohistochemistry of polyclonal antibodies again st CBs in the integrative centers of the brain:telencephalon,optic tectum,and ***-linked immunosorbent assay results showed a 1.7-fold increase in CBs expression in the rainbow trout brain at 1 week after unilateral eye injury compared with that in intact *** the ventricular and subventricular regions of the rainbow trout telencephalon,CBs+radial glia and neuroepithelial cells were *** unilateral eye injury

关键词： astrocyte-like cells glial fibrillary acidic protein hydrogen sulfide neuroepithelial cells neuroprotection radial glial cells rainbow trout(Oncorhynchus mykiss) reactive oxygen species unilateral eye injury

Recent advances and perspectives in next generation sequencing application to the genetic research of type 2 diabetes

在线全文

学校读者我要写书评

暂无评论

World Journal of Diabetes 2019年第7期10卷 376-395页

作者： Yulia A Nasykhova Yury A Barbitoff Elena A serebryakova Dmitry s Katserov Andrey s Glotov Laboratory of Biobanking and Genomic Medicine of Institute of Translation Biomedicine St.Petersburg State UniversitySt.Petersburg 199034Russia Department of Genomic Medicine D.O.Ott Research Institute of ObstetricsGynaecology and ReproductologySt.Petersburg 199034Russia Bioinformatics Institute St.Petersburg 194021Russia Department of Genetics and Biotechnology St.Petersburg State UniversitySt.Petersburg 199034Russia Department of Genetics City Hospital No.40St.Petersburg 197706Russia Institute of Living systems Immanuel Kant Baltic Federal UniversityKaliningrad 236016Russia

Type 2 diabetes(T2D)mellitus is a common complex disease that currently affects more than 400 million people worldwide and has become a global health ***-throughput sequencing technologies such as whole-genome and whole-exome sequencing approaches have provided numerous new insights into the molecular bases of *** advances in the application of sequencing technologies to T2D research include,but are not limited to:(1)Fine mapping of causal rare and common genetic variants;(2)Identification of confident genelevel associations;(3)Identification of novel candidate genes by specific scoring approaches;(4)Interrogation of disease-relevant genes and pathways by transcriptional profiling and epigenome mapping techniques;and(5)Investigation of microbial community alterations in patients with *** this work we review these advances in application of next-generation sequencing methods for elucidation of T2D pathogenesis,as well as progress and challenges in implementation of this new knowledge about T2D genetics in diagnosis,prevention,and treatment of the disease.

关键词： Type 2 diabetes Next-generation sequencing Epigenetics Genome-wide association study Microbiome

On the Homology of the Dual de Rham Complex

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica sinica,English series 2022年第10期38卷 1666-1676页

作者： Roman MIKHAILOV Laboratory of Modern Algebra and Applications St.Petersburg State University14th Line29bSaint Petersburg199178Russia st.petersburg Department of steklou Mathematical Institute Fontanka 27SaintPetersburg191023Russia

We study the homology of the dual de Rham complex as functors on the category of abelian *** give a description of homology of the dual de Rham complex up to degree 7 for free abelian groups and present a corrected ve... 详细信息

关键词： Dual de Rham complex polynomial functor divided powers derived functors

Probiotics and autoprobiotics for treatment of Helicobacter pylori infection

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2023年第20期11卷 4740-4751页

作者： Natalia V Baryshnikova Anastasia s Ilina Elena I Ermolenko Yury P Uspenskiy Alexander N suvorov Department of Molecular Microbiology Institute of Experimental MedicineSt.Petersburg 197376Russia Internal Diseases Department of stomatological Faculty Pavlov First St-Petersburg State Medical UniversitySt.Petersburg 197022Russia Laboratory of Medical and social Pediatric Problems St-Petersburg State Pediatric Medical UniversitySt.Petersburg 194100Russia Clinical Department Institute of Experimental MedicineSt.Petersburg 197376Russia Department of Faculty Therapy Named After V.A.Valdman St-Petersburg State Pediatric Medical UniversitySt.Petersburg 194100Russia

The article discusses various approaches for probiotic treatment of Helicobacter pylori(***)infection:Probiotics as an adjuvant treatment in the standard eradication therapy;probiotic strains as a monotherapy;and autoprobiotics as a *** refer to indigenous bifidobacteria,lactobacilli,or enterococci isolated from a specific individual,intended to restore his/her microbiota and improve his/her *** potential mechanisms of probiotic action against *** include correction of the gut microbiota,immunological effects(enhancement of humoral and cellular immunity,and reduction of oxidative stress),direct antagonistic effects against ***(such as colonization resistance and bacteriocin synthesis),and stimulation of local immunological protection(strengthening of the mucous protective barrier and reduction of gastric mucosa inflammation).The incorporation of probiotics into comprehensive eradication therapy shows promise in optimizing the treatment of *** *** can enhance the eradication rates of ***,reduce the occurrence and severity of side effects,and improve patient *** or autoprobiotic monotherapy can be considered as an alternative treatment approach in cases of allergic reactions and insufficient effectiveness of *** recommend including probiotics as adjunctive medications in *** ***,further randomized multicenter studies are necessary to investigate the effects of probiotics and autoprobiotics against ***,in order to gain a better understanding of their mechanisms of action.

关键词： Helicobacter pylori Probiotic Autoprobiotic Eradication Microbiota Gut Immunity