542 research outputs found
Introduction of open E-learning system as a factor of regional development
The article analyses the economic and socio-cultural premises for introducing the open e-learning in the Ural region, as well as the potential economic effect of this type of educational activity. The article strives to prove a regular pattern of the universities’ transition to e-learning, also in connection with the changes of the educational paradigm and the nature of the educational system management. The hypothesis of the paper is connected with bringing the economic dimension to a humanitarian concept of e-learning, which becomes more and more widespread. The methodology of the article is based on the recognition of the fact that the macroeconomic processes in the information society and the processes occurring in a particular industry — higher education — are of isomorphic nature. On the basis of the analysis of global experience and basic theoretical approaches to e-learning, including the Lifelong Learning concept, the authors make a conclusion of the progressive growth of interest in different countries and regions. The e-learning is treated primarily as a tool to improve quality and efficiency of the educational process. The accuracy of understanding functions and peculiarities of e-learning allows one to determine a positive economic effect of its application for the university, the region, and the employers. The article shows organisational mechanisms and financial model of implementing e-learning in the Ural Federal University. The description is made of the cost options for open-type e-learning course development, investment parameters for their establishment, as well as costs of implementing educational programmes with the application of e-learning. The analysis of the activities of Ural Federal University on implementing e-learning gives the opportunity to further imagine the effect from the introduction of e-learning in other universities in the region. The results of the research may be applied in the institutions of secondary and higher education in the decision concerning the volume and form of the e-learning system
Mobility of the SecA 2-helix-finger is not essential for polypeptide translocation via the SecYEG complex
The bacterial ATPase SecA and protein channel complex SecYEG form the core of an essential protein translocation machinery. The nature of the conformational changes induced by each stage of the hydrolytic cycle of ATP and how they are coupled to protein translocation are not well understood. The structure of the SecA–SecYEG complex revealed a 2-helix-finger (2HF) of SecA in an ideal position to contact the substrate protein and push it through the membrane. Surprisingly, immobilization of this finger at the edge of the protein channel had no effect on translocation, whereas its imposition inside the channel blocked transport. This analysis resolves the stoichiometry of the active complex, demonstrating that after the initiation process translocation requires only one copy each of SecA and SecYEG. The results also have important implications on the mechanism of energy transduction and the power stroke driving transport. Evidently, the 2HF is not a highly mobile transducing element of polypeptide translocation
Entanglement between a qubit and the environment in the spin-boson model
The quantitative description of the quantum entanglement between a qubit and
its environment is considered. Specifically, for the ground state of the
spin-boson model, the entropy of entanglement of the spin is calculated as a
function of , the strength of the ohmic coupling to the environment,
and , the level asymmetry. This is done by a numerical
renormalization group treatment of the related anisotropic Kondo model. For
, the entanglement increases monotonically with , until it
becomes maximal for . For fixed , the entanglement
is a maximum as a function of for a value, .Comment: 4 pages, 3 figures. Shortened version restricted to groundstate
entanglemen
Partonic energy loss in ultrarelativistic heavy ion collisions: jet suppression versus jet fragmentation softening
We discuss the modification of a jet fragmentation function due to
medium-induced partonic energy loss in context of leading particle observables
in ultrarelativistic nucleus-nucleus interactions. We also analyze the relation
between in-medium softening jet fragmentation function and suppression of the
jet rates due to energy loss outside the jet cone. The predicted
anti-correlation between two effects allows to probe a fraction of partonic
energy loss carried out of the jet cone and truly lost to the jet.Comment: LaTeX, 12 pages including 2 eps-figure
A continuous time random walk model for financial distributions
We apply the formalism of the continuous time random walk to the study of
financial data. The entire distribution of prices can be obtained once two
auxiliary densities are known. These are the probability densities for the
pausing time between successive jumps and the corresponding probability density
for the magnitude of a jump. We have applied the formalism to data on the US
dollar/Deutsche Mark future exchange, finding good agreement between theory and
the observed data.Comment: 14 pages, 5 figures, revtex4, submitted for publicatio
Alpha scattering and capture reactions in the A = 7 system at low energies
Differential cross sections for He- scattering were measured in
the energy range up to 3 MeV. These data together with other available
experimental results for He and H scattering were
analyzed in the framework of the optical model using double-folded potentials.
The optical potentials obtained were used to calculate the astrophysical
S-factors of the capture reactions HeBe and
HLi, and the branching ratios for the transitions into
the two final Be and Li bound states, respectively. For
HeBe excellent agreement between calculated and
experimental data is obtained. For HLi a value
has been found which is a factor of about 1.5 larger than the adopted value.
For both capture reactions a similar branching ratio of has been obtained.Comment: submitted to Phys.Rev.C, 34 pages, figures available from one of the
authors, LaTeX with RevTeX, IK-TUW-Preprint 930540
ELM triggering conditions for the integrated modeling of H-mode plasmas
Recent advances in the integrated modeling of ELMy H-mode plasmas are
presented. A model for the H-mode pedestal and for the triggering of ELMs
predicts the height, width, and shape of the H-mode pedestal and the frequency
and width of ELMs. Formation of the pedestal and the L-H transition is the
direct result of ExB flow shear suppression of anomalous transport. The
periodic ELM crashes are triggered by either the ballooning or peeling MHD
instabilities. The BALOO, DCON, and ELITE ideal MHD stability codes are used to
derive a new parametric expression for the peeling-ballooning threshold. The
new dependence for the peeling-ballooning threshold is implemented in the ASTRA
transport code. Results of integrated modeling of DIII-D like discharges are
presented and compared with experimental observations. The results from the
ideal MHD stability codes are compared with results from the resistive MHD
stability code NIMROD.Comment: 12th International Congress on Plasma Physics, 25-29 October 2004,
Nice (France
Introduction to M Theory and AdS/CFT Duality
An introductory survey of some of the developments that have taken place in
superstring theory in the past few years is presented. The main focus is on
three particular dualities. The first one is the appearance of an 11th
dimension in the strong coupling limit of the type IIA theory, which give rise
to M theory. The second one is the duality between the type IIB theory
compactified on a circle and M theory on a two-torus. The final topic is an
introduction to the recently proposed duality between superstring theory or M
theory on certain anti de Sitter space backgrounds and conformally invariant
quantum field theories.Comment: 26 pages; To be published in the Proceedings of a conference held in
Corfu, Greece in September 1998. v2: reference adde
Integrating coronary atherosclerosis burden and progression with coronary artery disease risk factors to guide therapeutic decision making (vol 136, page 260, 2023)
Cardiolog
A Model for the Development of the Rhizobial and Arbuscular Mycorrhizal Symbioses in Legumes and Its Use to Understand the Roles of Ethylene in the Establishment of these two Symbioses
We propose a model depicting the development of nodulation and arbuscular mycorrhizae. Both processes are dissected into many steps, using Pisum sativum L. nodulation mutants as a guideline. For nodulation, we distinguish two main developmental programs, one epidermal and one cortical. Whereas Nod factors alone affect the cortical program, bacteria are required to trigger the epidermal events. We propose that the two programs of the rhizobial symbiosis evolved separately and that, over time, they came to function together. The distinction between these two programs does not exist for arbuscular mycorrhizae development despite events occurring in both root tissues. Mutations that affect both symbioses are restricted to the epidermal program. We propose here sites of action and potential roles for ethylene during the formation of the two symbioses with a specific hypothesis for nodule organogenesis. Assuming the epidermis does not make ethylene, the microsymbionts probably first encounter a regulatory level of ethylene at the epidermis–outermost cortical cell layer interface. Depending on the hormone concentrations there, infection will either progress or be blocked. In the former case, ethylene affects the cortex cytoskeleton, allowing reorganization that facilitates infection; in the latter case, ethylene acts on several enzymes that interfere with infection thread growth, causing it to abort. Throughout this review, the difficulty of generalizing the roles of ethylene is emphasized and numerous examples are given to demonstrate the diversity that exists in plants
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