INTERNAL INTESTINAL FISTULAE CAUSED BY AMOEBIASIS

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Effect of culture conditions on viability of mouse and rat embryos developed in vitro

Currently in vitro culture of mouse preimplantation embryos has become a very important technique to investigate different mechanisms of early embryogenesis. However, there is a big difference in the preimplantation development between mammalian species. Despite close relatedness to mice, in vitro cultivation of rat preimplantation embryos is still delicate and needs further investigation and optimizations. In this study we have compared the in vitro developmental potential of mouse and rat embryos cultured at different culture conditions in parallel experiments. Interestingly, mouse zygotes developed in vitro until blastocyst stage even in inadequate medium without any phosphates and with low osmolarity which was formulated especially for cultivation of rat embryos. Rat parthenotes and zygotes developed in M16 medium formulated for mouse embryos only till 2-cell stage and further development is blocked completely at this stage. Moreover, developmental ability of rat embryos in vitro was significantly lower in comparison with mouse even in special rat mR1ECM medium. Mouse and rat embryos at 2-cell stage obtained in vivo developed until blastocyst stages significantly more efficiently compared to zygotes. Culture of mouse zygotes in glass capillaries resulted in a significantly higher rate of morula and blastocyst development compared with dishes. The Well-of-the-Well system resulted in a significant improvement when compared with dishes for the culture of rat zygotes only until morula stage. Reduced oxygen tension increased the developmental rate of rat but not mouse zygotes until blastocyst stage. This study demonstrates that development of early preimplantation embryos is altered by different culture conditions and show strong differences even between two related species such as mice and rats. Therefore, for understanding the fundamental mechanisms of early mammalian development it is very important to use embryos of various species

Evidence of Vortex Jamming in Abrikosov Vortex Flux Flow Regime

We report on dynamics of non-local Abrikosov vortex flow in mesoscopic superconducting Nb channels. Magnetic field dependence of the non-local voltage induced by the flux flow shows that vortices form ordered vortex chains. Voltage asymmetry (rectification) with respect to the direction of vortex flow is evidence that vortex jamming strongly moderates vortex dynamics in mesoscopic geometries. The findings can be applied to superconducting devices exploiting vortex dynamics and vortex manipulation, including superconducting wires with engineered pinning centers.Comment: 5 pages, 3 figure

Quantifying spin Hall angles from spin pumping: Experiments and Theory

Spin Hall effects intermix spin and charge currents even in nonmagnetic materials and, therefore, ultimately may allow the use of spin transport without the need for ferromagnets. We show how spin Hall effects can be quantified by integrating permalloy/normal metal (N) bilayers into a coplanar waveguide. A dc spin current in N can be generated by spin pumping in a controllable way by ferromagnetic resonance. The transverse dc voltage detected along the permalloy/N has contributions from both the anisotropic magnetoresistance (AMR) and the spin Hall effect, which can be distinguished by their symmetries. We developed a theory that accounts for both. In this way, we determine the spin Hall angle quantitatively for Pt, Au and Mo. This approach can readily be adapted to any conducting material with even very small spin Hall angles.Comment: 4 pages, 4 figure

“Success stories” as an evidence form: Organizational legitimization in an international technology assistance project

This paper looks at how evidence and success were constructed in Biblionet - Global Libraries Romania, an NGO-led, technology-based project in Romania. The main focus of Biblionet is to provide public access to computers and the internet in public libraries throughout Romania. Here, we discuss how project staff relied on one particular set of measures to legitimatize, validate and sell their project to audiences in Romania and in the West. This NGO tended to demonstrate success using relatively weak measures. Perhaps the most suspect of these were, paradoxically, appeals to science, that is to say, hard numbers and and one-time, one-off inspirational success stories that would play well in popular media. Our research on the Biblionet program in Salaj County, Romania identified trends in information, technology, and library use which either fell outside of or were not captured by the NGO\u27s quantitative metrics. This is despite the fact that these trends seemed to indicate a greater potential for this project\u27s long-term success than the ones the NGO itself employed. This raises a number of issues that neither the anthropology of development nor the anthropology of science have taken seriously. In particular, this paper suggests that the role lay or folk notions of empiricism and success play in the legitimization and evaluation of NGO efforts requires more attention than it has received in the literature so far

“Success stories” as an evidence form: Organizational legitimization in an international technology assistance project

This paper looks at how evidence and success were constructed in Biblionet - Global Libraries Romania, an NGO-led, technology-based project in Romania. The main focus of Biblionet is to provide public access to computers and the internet in public libraries throughout Romania. Here, we discuss how project staff relied on one particular set of measures to legitimatize, validate and sell their project to audiences in Romania and in the West. This NGO tended to demonstrate success using relatively weak measures. Perhaps the most suspect of these were, paradoxically, appeals to science, that is to say, hard numbers and and one-time, one-off inspirational success stories that would play well in popular media. Our research on the Biblionet program in Salaj County, Romania identified trends in information, technology, and library use which either fell outside of or were not captured by the NGO\u27s quantitative metrics. This is despite the fact that these trends seemed to indicate a greater potential for this project\u27s long-term success than the ones the NGO itself employed. This raises a number of issues that neither the anthropology of development nor the anthropology of science have taken seriously. In particular, this paper suggests that the role lay or folk notions of empiricism and success play in the legitimization and evaluation of NGO efforts requires more attention than it has received in the literature so far

Surface-enhanced optical third-harmonic generation in Ag island films

Surface-enhanced optical third-harmonic generation (THG) is observed in silver island films. The THG intensity from Ag nanoparticles is enhanced by more than two orders of magnitude with respect to the THG intensity from a smooth and homogeneous silver surface. This enhancement is attributed to local plasmon excitation and resonance of the local field at the third-harmonic wavelength. The diffuse and depolarized component of the enhanced THG is associated with the third-order hyper-Rayleigh scattering in a 2-D random array of silver nanoparticles.Comment: 4 pages, 2 figure

Frequency content analysis of R&D projects of the EC framework programs with the participation of Euro-Mediterranean partnership countries

On the basis of the CORDIS data on FP5-FP7 programs the activity of MEDA countries in these projects was studied in the priority areas of action. A content analysis of the participation MEDA country organizations in FP5-FP7 has been performed and 25 large-scale investigation areas have been identifiedyesBelgorod State Universit