2,422 research outputs found

    Coulomb drag between one-dimensional conductors

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    We have analyzed Coulomb drag between currents of interacting electrons in two parallel one-dimensional conductors of finite length LL attached to external reservoirs. For strong coupling, the relative fluctuations of electron density in the conductors acquire energy gap MM. At energies larger than Γ=const×vexp(LM/v)/L+Γ+\Gamma = const \times v_- \exp (-LM/v_-)/L + \Gamma_{+}, where Γ+\Gamma_{+} is the impurity scattering rate, and for L>v/ML>v_-/M, where vv_- is the fluctuation velocity, the gap leads to an ``ideal'' drag with almost equal currents in the conductors. At low energies the drag is suppressed by coherent instanton tunneling, and the zero-temperature transconductance vanishes, indicating the Fermi liquid behavior.Comment: 5 twocolumn pages in RevTex, added 1 eps-Figure and calculation of trans-resistanc

    Organizational and legal bases of formation of insurance activity: retrospective analysis (on the materials of the ukrainian provinces as part of the Russian empire)

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    Пономаренко, П. О. Організаційно-правові засади становлення страхової діяльності: ретроспективний аналіз (на матеріалах українських губерній у складі Російської імперії) [Електронний ресурс] / Пономаренко П. О. // Юридичний науковий електронний журнал. - 2020. - № 3, т. 2. - С. 29-34. - Режим доступу : http://lsej.org.ua/3-2_2020/4.pdf.Досліджено організаційно-правові засади становлення страхової діяльності з точки зору ретроспективного аналізу на матеріалах українських губерній у складі Російської імперії. Зазначено, що першочергові аспекти еволюційного зародження відносин колективної (страхової) взаємодопомоги, страхових відносин і страхових ідей формувалися під впливом різних політичних, економічних, історичних та культурних процесів, що відбуваються в державі.The scientific article is devoted to research and complex analysis of organizational and legal bases of formation of insurance activity from the point of view of the retrospective analysis on materials of the Ukrainian provinces as a part of the Russian empire. Taking into account the doctrinal study, it is stated that the primary aspects of the evolutionary origin of relations of collective (insurance) mutual assistance, insurance relations and insurance ideas were formed under the influence of various political, economic, historical and cultural processes taking place in the state. The emergence of legislative and scientific support for insurance and insurance ideas at a time when the economy was developing within the rigid framework of serfdom, was still associated much more as a "tribute to European fashion." In Western countries at this time insurance has already been widely developed, and the first works of a scientific nature on life insurance were published. Thus, the state of social relations, economics, finance and education have not yet contributed to the emergence in the XVIII century of domestic legal science and professional financial education, but the trend towards their emergence was already quite clear and meaningful. In the XIX century, financial and insurance science, as well as insurance education were largely associated with political economy research and the process of formation of financial institutions, the tax system. This influenced the emergence of analytical research of domestic scientists and practitioners, differing in the breadth of general economic horizons, deep knowledge of contemporary political and economic schools, scientific understanding of the processes in economic life. Further, the development of insurance activity as an economic tool posed the task of considering a wide range of issues related to the formation of insurance protection in all sectors of the economy.Исследованы организационно-правовые основы становления страховой деятельности с точки зрения ретроспективного анализа на материалах украинских губерний в составе Российской империи. Отмечено, что первоочередные аспекты эволюционного зарождения отношений коллективной (страховой) взаимопомощи, страховых отношений и страховых идей формировались под влиянием происходящих в государстве различных политических, экономических, исторических и культурных процессов

    Zero-Point Fluctuations and the Quenching of the Persistent Current in Normal Metal Rings

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    The ground state of a phase-coherent mesoscopic system is sensitive to its environment. We investigate the persistent current of a ring with a quantum dot which is capacitively coupled to an external circuit with a dissipative impedance. At zero temperature, zero-point quantum fluctuations lead to a strong suppression of the persistent current with decreasing external impedance. We emphasize the role of displacement currents in the dynamical fluctuations of the persistent current and show that with decreasing external impedance the fluctuations exceed the average persistent current.Comment: 4 pages, 2 eps figure

    РОЛЬ ІНФОРМАТИЗАЦІЇ ФАРМАЦЕВТИЧНОГО РИНКУ В ЗАБЕЗПЕЧЕННІ УПРАВЛІННЯ ОБІГОМ ЛІКАРСЬКИХ ЗАСОБІВ

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    The controversial questions of the pharmaceutical market informatization are considered. The main principles and legal frameworks to manage population ensure with medicines based on use of information technology are proposed. The logic and conception framework of related information automatization for hospitals and population under the current legislation are discussed.Рассмотрены дискуссионные вопросы информатизации фармацевтического рынка. Предложены основные прин­ципы и нормативно-правовые основы управления процессами обеспечения населения лекарственными сред­ствами на основе широкого использования информационных технологий. Рассмотрены логика и концептуальные основы автоматизации обеспечения учреждений здравоохранения и населения соответствующей информацией в рамках действующего законодательства.Розглянуто дискусійні питання інформатизації фармацевтичного ринку. Запропоновано основні принципи та нор­мативно-правові засади управління процесами забезпечення населення лікарськими засобами на основі широко­го використання інформаційних технологій. Розглянуті логіка та концептуальні засади автоматизації забезпечення закладів охорони здоров’я та населення відповідною інформацією в межах чинного законодавства

    Thermodynamic and kinetic basis for recognition and repair of 8-oxoguanine in DNA by human 8-oxoguanine-DNA glycosylase

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    We have used a stepwise increase in ligand complexity approach to estimate the relative contributions of the nucleotide units of DNA containing 7,8-dihydro-8-oxoguanine (oxoG) to its total affinity for human 8-oxoguanine DNA glycosylase (OGG1) and construct thermodynamic models of the enzyme interaction with cognate and non-cognate DNA. Non-specific OGG1 interactions with 10–13 nt pairs within its DNA-binding cleft provides approximately 5 orders of magnitude of its affinity for DNA (ΔG° approximately −6.7 kcal/mol). The relative contribution of the oxoG unit of DNA (ΔG° approximately −3.3 kcal/mol) together with other specific interactions (ΔG° approximately −0.7 kcal/mol) provide approximately 3 orders of magnitude of the affinity. Formation of the Michaelis complex of OGG1 with the cognate DNA cannot account for the major part of the enzyme specificity, which lies in the kcat term instead; the rate increases by 6–7 orders of magnitude for cognate DNA as compared with non-cognate one. The kcat values for substrates of different sequences correlate with the DNA twist, while the KM values correlate with ΔG° of the DNA fragments surrounding the lesion (position from −6 to +6). The functions for predicting the KM and kcat values for different sequences containing oxoG were found

    Immune epitope database analysis resource

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    The immune epitope database analysis resource (IEDB-AR: http://tools.iedb.org) is a collection of tools for prediction and analysis of molecular targets of T- and B-cell immune responses (i.e. epitopes). Since its last publication in the NAR webserver issue in 2008, a new generation of peptide:MHC binding and T-cell epitope predictive tools have been added. As validated by different labs and in the first international competition for predicting peptide:MHC-I binding, their predictive performances have improved considerably. In addition, a new B-cell epitope prediction tool was added, and the homology mapping tool was updated to enable mapping of discontinuous epitopes onto 3D structures. Furthermore, to serve a wider range of users, the number of ways in which IEDB-AR can be accessed has been expanded. Specifically, the predictive tools can be programmatically accessed using a web interface and can also be downloaded as software packages

    Coulomb drag shot noise in coupled Luttinger liquids

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    Coulomb drag shot noise has been studied theoretically for 1D interacting electron systems, which are realized e.g. in single-wall nanotubes. We show that under adiabatic coupling to external leads, the Coulomb drag shot noise of two coupled or crossed nanotubes contains surprising effects, in particular a complete locking of the shot noise in the tubes. In contrast to Coulomb drag of the average current, the noise locking is based on a symmetry of the underlying Hamiltonian and is not limited to asymptotically small energy scales.Comment: 4 pages Revtex, accepted for publication in PR

    Electron transport through a mesoscopic metal-CDW-metal junction

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    In this work we study the transport properties of a finite Peierls-Fr\"ohlich dielectric with a charge density wave of the commensurate type. We show that at low temperatures this problem can be mapped onto a problem of fractional charge transport through a finite-length correlated dielectric, recently studied by Ponomarenko and Nagaosa [Phys. Rev. Lett {\bf 81}, 2304 (1998)]. The temperature dependence of conductance of the charge density wave junction is presented for a wide range of temperatures.Comment: Latex, Revtex 3.0, 7 pages, 2 EPS figures (uses epfs

    The effects of SN Ps in the regions of positioning RNA polymerase II on the TBP/promoter affinity in the genes of human circadian clock

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    Genetic variability in the genes of circadian clock is manifested as the phenotypic variability of physiological functions and behavior as well as disorders of the function of not only the clock but also other systems, leading to the development of a pathologies. We analyzed the influence of SNPs localized in the [–70, –20] region from the transcription start site of the gene on TBP / promoter affinity in two groups of genes that are components of the system of human circadian clock. The first group comprises the genes of the circadian oscillator core (11 genes); the second, the genes of the nearest regulatory environment of the circadian oscillator (21 genes). A group for comparison included genes with another function (31 genes). The SNP_TATA_Comparator web service was used for prediction of the effect of SNPs in the regions of positioning of RNA polymerase II on the dissociation constant for TBP / promoter. It was shown that the number of SNP markers reducing the TBP / promoter affinity in the first group of genes significantly lower than the number of SNP markers increasing affinity (α < 10–3). The reverse was true of the comparison group: SNP markers reduced TBP / promoter affinity to a significantly greater extent than the SNP marker increased affinity (α < 10–6). This property may be a characteristic feature of genes  of the circadian oscillator. These predictions are important for identification of candidate SNP markers of various pathologies associated with the dysfunction of circadian clock genes for further testing them in experimental and clinical studies, as well as for verification of mathematical models of the circadian oscillator

    Biomedical and candidate SN P markers of chronopathologies can significantly change affinity of ТАТА -binding protein for human gene promoters

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    Computational analysis of millions of unannotated SNPs from the 1000 Genomes Project may speed up the search for biomedical SNP markers. We combined the analysis of SNPs in the binding sites of ТАТА - binding protein (ТВР) using a previously described W eb service (http://beehive.bionet.nsc.ru/cgi-bin/mgs/ tatascan/start.pl) with a keyword search for biochemicalmarkers of chronopathologies, which correspond to clinical manifestations of these SNPs. In the [–70; –20] region of promoters of 14 human genes (location of proven binding sites of ТВР), we found 32 known and candidate SNP markers of circadian- rhythm disturbances, including rs17231520 and rs569033466 (both: risk of chronopathologies in liver); rs35036378 (behavioral chronoaberrations); rs549858786 (rheumatoid arthritis with a chronoaberration of IL1B expression); rs563207167, rs11557611, and rs5505 (all three: chronopathologies of the tumor – host balance, blood pressure, and the reproductive system); rs1143627 (bipolar disorder with circadian dependence of diagnosis and treatment); rs16887226 and rs544850971 (both: lowered resistance to endotoxins because of the imbalance between the circadian and immune systems); rs367732974 and rs549591993 (both: circadian dependence of heart attacks); rs563763767 (circadian dependence of myocardial infarction); rs2276109 and rs572527200 (both: circadian dependence of asthma attacks); rs34223104, rs563558831, and rs10168 (circadian optima of treatment with methotrexate and cyclophosphamide); and rs397509430, rs33980857,rs34598529, rs33931746, rs33981098, rs34500389, rs63750953, rs281864525, rs35518301, and rs34166473 (all: neurosensory hearing loss and restless legs syndrome). For these SNPs, we evaluated α (significance) of changes in the affinity of ТВР for promoters, where increased affinity corresponds to overexpression of the genes, and decreased affinity to deficient expression (Z-test). Verification of these 32 SNP markers according to clinical standards and protocols may advance the field of predictive preventive personalized medicine
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