Railway infrastructures in mountain areas often develop along hillslopes affected by geomorphological and hydrogeological processes which might lead hazardous events. Therefore, specific tools for ...risk analysis and management are required. This paper develops a new rating system (Railway Hydrogeological Management System, RHMS), based on a heuristic method which considers the susceptibility to different types of slope instabilities, as well as the peculiar features affecting the railway vulnerability. The proposed method introduces an iterative approach for the risk assessment, based on the definition of acceptability thresholds for the residual risk. The application of this method to a test area pointed out its feasibility, as well as its operational capability to identify the critical sections of the infrastructure, in which protection or mitigation measures are needed in order to reduce the risk.
We describe isolation and characterization of the bovine ortholog of POU5F1 ( bPOU5F1 ) encoding octamer-binding transcription factor-4 (Oct-4). The organization of bPOU5F1 is similar to its human ...and murine orthologs, and it shares 90.6% and 81.7% overall identity at the protein level, respectively.
Transient transfection of luciferase reporter constructs in murine P19 embryonal carcinoma cells demonstrated that bPOU5F1 has a functional promoter and contains two enhancer elements, of which one is repressed by retinoic acid. bPOU5F1 was mapped to the major histocompatibility complex on chromosome 23. bPOU5F1 mRNA was detected by nested reverse transcription-polymerase chain reaction in immature oocytes and in in vitro-produced
preattachment-stage embryos. Oct-4 in oocytes and in vitro-produced preattachment-stage embryos was demonstrated by indirect
immunofluorescence. Confocal laser scanning microscopy revealed Oct-4 in both the inner cell mass and trophoblast cells of
the blastocyst until Day 10 of development. Immunofluorescence performed on the outgrowths formed at Day 13 postfertilization
from in vitro-produced Day 8 blastocysts showed Oct-4 staining in all cells. This expression pattern suggests that bPOU5F1 acts early in bovine embryonic development but that its expression is not restricted to pluripotent cells of the blastocyst.
Oocyte and cumulus cells are interconnected by an extensive network of gap junctions (GJ) formed by connexin 43. In the present study the functional and morphological status of GJ was investigated ...during in vitro maturation of bovine oocytes using media known to induce different rates of maturation and developmental competence as well as different levels of cumulus expansion and intracellular concentrations of cAMP. GJ functional condition was studied by microinjection of the fluorescent dye Lucyfer Yellow in cumulus-enclosed oocytes and the intracellular distribution of connexin 43 was examined by immunofluorescence immunocytochemistry. Both functional and morphological analysis of GJ between oocytes and cumulus cells indicated that high maturation and development rates are accompanied by the prolonged persistence of permeable communications, which, however, are independent from cumulus expansion. On the contrary, the premature interruption of such communications was linked to low maturation and development. When these results were correlated to the measurements of intracellular levels of cAMP it was observed that cumulus expansion, GJ permeability and good quality maturation require the highest levels of cAMP. Intermediate cAMP levels determine GJ permeability and good quality maturation in the absence of cumulus expansion while below a threshold level of cAMP, oocyte maturation is defective with a premature interruption of communications through GJ and lack of cumulus expansion which lead to poor development.
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