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1.
Transplantation of various types of stem cells as a possible therapy for stroke has been tested for years, and the results are promising. Recent investigations have shown that the administration of the conditioned media obtained after stem cell cultivation can also be effective in the therapy of the central nervous system pathology (hypothesis of their paracrine action). The aim of this study was to evaluate the therapeutic effects of the conditioned medium of hiPSC-derived glial and neuronal progenitor cells in the rat middle cerebral artery occlusion model of the ischemic stroke. Secretory activity of the cultured neuronal and glial progenitor cells was evaluated by proteomic and immunosorbent-based approaches. Therapeutic effects were assessed by overall survival, neurologic deficit and infarct volume dynamics, as well as by the end-point values of the apoptosis- and inflammation-related gene expression levels, the extent of microglia/macrophage infiltration and the numbers of formed blood vessels in the affected area of the brain. As a result, 31% of the protein species discovered in glial progenitor cells-conditioned medium and 45% in neuronal progenitor cells-conditioned medium were cell type specific. The glial progenitor cell-conditioned media showed a higher content of neurotrophins (BDNF, GDNF, CNTF and NGF). We showed that intra-arterial administration of glial progenitor cells-conditioned medium promoted a faster decrease in neurological deficit compared to the control group, reduced microglia/macrophage infiltration, reduced expression of pro-apoptotic gene Bax and pro-inflammatory cytokine gene Tnf, increased expression of anti-inflammatory cytokine genes (Il4, Il10, Il13) and promoted the formation of blood vessels within the damaged area. None of these effects were exerted by the neuronal progenitor cell-conditioned media. The results indicate pronounced cytoprotective, anti-inflammatory and angiogenic properties of soluble factors secreted by glial progenitor cells.  相似文献   
2.
In many Grid infrastructures different kinds of information services are in use, which utilize different incompatible data structures and interfaces to encode and provide their data. Homogeneous monitoring of these infrastructures with the monitoring data being accessible everywhere independently of the middleware which provided it, is the basis for a consistent status reporting on the Grids’ resources and services. Thus, interoperability or interoperation between the different information services in a heterogeneous Grid infrastructure is required. Monitoring data must contain the identity of the affected Virtual Organization (VO) so that it can be related to the resources and services the VO has allocated to enable VO-specific information provision. This paper describes a distributed architecture for an interoperable information service, which combines data unification and categorization with policies for VO membership, VO resource management and data transformations. This service builds the basis for an integrated and interoperating monitoring of Grids, which provide their data to more than one VO and utilize heterogeneous information services.  相似文献   
3.
Abstract— A novel green laser source, based on a monolithic cavity microchip laser platform, has been developed. The laser is designed to be a part of a miniature and efficient RGB light source for microdisplay‐based mobile projector devices. The use of highly efficient, periodically poled MgO‐doped lithium niobate as the non‐linear frequency doubler allows for a significant increase in the overall efficiency of the green microchip laser. Specifically, a 50–150‐mW green output with a wall‐plug efficiency exceeding 10% in the temperature range of greater than 40°C has been demonstrated. A compact package for this laser source with a volume less than 0.33 cm3 is discussed and results of performance tests are presented.  相似文献   
4.
当考虑旋转惯性的影响时,流经管道横截面的液体在剪切作用下,会产生小振动.本文推导出无量纲参数表示的系统微分方程.对于某些问题的确定值,使用Galerkin方法,可以得到主振动频率和临界速度.在此基础上,还将研究结果和经典理论值进行了比较.  相似文献   
5.
The binding energy of a hydrogen-like impurity in a thin size-quantized wire of the InSb/GaAs semiconductors with Kane’s dispersion law in a magnetic field B parallel to the wire axis has been calculated as a function of the radius of the wire and magnitude of B, using a variational approach. It is shown that when wire radius is less than the Bohr radius of the impurity, the nonparabolicity of dispersion law of charge carriers leads to a considerable increase of the binding energy in the magnetic field, as well as to a more rapid growth of binding energy with growth of B.  相似文献   
6.
The Fourier series of a smooth function on a compact interval usually has slow convergence due to the Gibbs phenomena. A class of Fourier-Pade approximations is introduced and studied for performing a boundary correction. Additional acceleration is achieved by applying Fourier–Bernoulli scheme.  相似文献   
7.
This paper describes a package for calculations of expressions with Dirac matrices. Advantages over existing similar packages are described. MatrixExp package is intended for simplification of complex expressions involving γ-matrices, providing such tools as automatic Feynman parameterization, integration in d-dimensional space, sorting and grouping of results in a given order. Also, in comparison with the existing similar package Tracer, the presented package MatrixExp has more enhanced input possibility. User-available functions of MatrixExp package are described in detail. Also an example of calculation of Feynman diagram for process bsγg with application of functions of MatrixExp package is presented.

Program summary

Title of program:MatrixExpCatalogue identifier:ADWBProgram summary URL:http://cpc.cs.qub.ac.uk/summaries/ADWBProgram obtainable from:CPC Program Library, Queen's University of Belfast, N. IrelandLicensing provisions:noneProgramming language:MATHEMATICAComputer:PC PentiumOperating system:WindowsNo. of lines in distributed program, including test data, etc.: 1551No. of bytes in distributed program, including test data, etc.: 16 040Distribution format:tar.gzRAM:loading the package uses approx. 3 500 000 bytes of RAM. However memory required for calculations depends heavily on the expressions in the view, as the package uses recursive functions, and MATHEMATICA dynamically allocates memory. Package has been tested to work on PC Pentium II 233 MHz with 128 Mb of memory calculating typical diagrams of contemporary calculations.Nature of problem:Feynman diagram calculation, simplification of expressions with γ-matricesSolution method:Analytic transformations, dimensional regularization, Feynman parameterizationRestrictions:MatrixExp package works only with single line of expressions (G[l1,]), in contrast to the Tracer package that works with multiple lines, i.e., the following is possible in Tracer, but not in MatrixExp: G[l1,]**G[l2,]**G[l3,], which will return the result of G[l1,]**G[l1,]**G[l1,]….Unusual features:noneRunning time:Seconds for expressions with several different γ-matrices on Pentium IV 1.8 GHz and of the order of a minute on Pentium II 233 MHz. Calculation times rise with the number of matrices.  相似文献   
8.
Dynamics are the most important problems in the microgrid operation. In the islanded microgrid, the mismatch of parallel operations of inverters during dynamics can result in the instability. This paper considers severe dynamics which can occur in the microgrid. Microgrid can have different configurations with different load and generation dynamics which are facing voltage disturbances. As a result, microgrid has many uncertainties and is placed in the distribution network where is full of voltage disturbances. Moreover, characteristics of the distribution network and distributed energy resources in the islanded mode make microgrid vulnerable and easily lead to instability. The main aim of this paper is to discuss the suitable mathematical modeling based on microgrid characteristics and to design properly inner controllers to enhance the dynamics of microgrid with uncertain and changing parameters. This paper provides a method for inner controllers of inverter-based distributed energy resources to have a suitable response for different dynamics. Parallel inverters in distribution networks were considered to be controlled by nonlinear robust voltage and current controllers. Theoretical prove beyond simulation results, reveal evidently the effectiveness of the proposed controller.  相似文献   
9.
This article provides new insights into the aerothermoelastic stability of thin plates. Particularly, the issue of loss of stability of an isotropic plate-strip of constant thickness immersed in a supersonic flow field and subjected to a variable temperature field through the thickness is examined. Using the basic principles of the theory of aerothermoelasticity of isotropic bodies, the theories of flexible panels, and the linear law of temperature field through the thickness of the panel, the stability equations and associated boundary conditions are obtained. As expected, the coefficients of the aerothermoelastic governing equations depend on the thermal load, and consequently the panel-flutter critical speed depends on temperature. The model takes into account quadratic and cubic aerodynamic non-linearities as well as cubic geometric non-linearities. Due to the inhomogeneity of the temperature field distribution across the thickness plate buckling instability occurs. This instability accounts for the deformed shape of the plate and the stability boundary depends on the variables characterizing the flow speed, the temperature of the middle plane and the temperature gradient in the direction normal to the plane. It is shown that the combined effect of the temperature field and free-stream regulates the process of stability and the temperature field can significantly change the flutter critical speed and flutter behavior. The problem of stability is also considered in the non-linear framework. The existence and behavior of flutter-type vibrations is investigated at pre- and post-critical speeds. The influence of the temperature field on the dependency of the limit cycle amplitude as a function of speed is studied. Results and discussions are presented along with pertinent concluding remarks.  相似文献   
10.
South-central Arkansas (AR) is home to major manufacturing facilities for brominated flame retardant chemicals (BFRs) in the U.S. Unintended release during production may have caused accumulation of the BFRs in the local environment. In this work, sediment cores were collected from six water bodies in AR, including three located close to the BFR manufacturing facilities in El Dorado and Magnolia, to investigate past and recent deposition histories. A total of 49 polybromodiphenyl ethers (PBDEs) and decabromodiphenyl ethane (DBDPE) were detected, with concentrations as high as 57?000 and 2400 ng/g dry weight for decabromodiphenyl ether (BDE209) and DBDPE, respectively. Log-log regression of BDE209 and DBDPE surface concentrations versus distance to known BFR manufacturing facilities fit the Gaussian Plume Dispersion model, and showed that, if the distance is shortened by half, concentrations of BDE209 and DBDPE would increase by 5-fold. The spatial distribution and temporal trend of the contamination indicate that the manufacturing of PBDEs and DBDPE is the primary source for these compounds in the environment of southern Arkansas. Interestingly, the occurrence of debromination of PBDEs in the sediments of a previously used wastewater sludge retention pond in Magnolia is indicated by the presence of congeners that had not been detected in any commercial PBDE mixtures and by increased fractions of lower brominated congeners relative to higher brominated congeners. Two unknown brominated compounds were detected in the sediments, and identified as nonabromodiphenyl ethanes.  相似文献   
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