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In order to evaluate the vulnerability of highway slope hazard, the second-class highway from Wenshan to Tianbao in Yunnan province (Wentian highway) was taken as an example; three factors including economic density, road repair lime and road bypass capacity were used lo establish the index system of vulnerability assessment of highway slope hazard considering the function of highway; according lo the quantification and superposition calculation of indexes in ArcGIS platform, the vulnerability assessment of highway slope hazard was carried out; the vulnerabilities of different sections were classified and discussed according lo the evaluation result, and the methods to reduce the vulnerability of slope hazard were proposed. The results show that the vulnerabilities of different sections in Wentian highway are 0.07-1.00, and 30. 75% of Wentian highway is high or extremely high; the vulnerability for 3. 96% of Wentian highway is extremely high, and the ratio of length of bypass highway to length of corresponding Wentian highway is large, so that the length of bypass highway can be deceased in future highway construction in order to decease the vulnerability of highway slope hazard; although the economic density of the section near the starting point of Wentian highway is maximum, vulnerability of this section is moderate because of the shortest road repair time, dense road network an shorter length of bypass highway. [ABSTRACT FROM AUTHOR]

Abstract: This study was designed to examine the reduced incidence of normal fertilization in vitrified ovine oocytes. After in vitro maturation for 24h, the oocytes were randomly allocated into three groups: (1) untreated (control), (2) exposed to vitrification solution (VS) without being plunged into liquid nitrogen (toxicity), or (3) vitrified by open-pulled straw method (vitrification). In experiment 1, the treated and control oocytes were matured for another 2h, and the oocytes were then in vitro fertilized for 12h to examine sperm penetration. The percentage of monospermy in toxicity group (29.3%) and vitrification group (28.2%) dramatically decreased compared to the control group (45.0%) (P <0.05). To find the mechanism that the VS decreased the monospermy, some treated and control oocytes were used to test the distribution of CG and the resistance of zona pellucida (ZP) to 0.1% pronase E immediately (IVM 24h), after another 2h of maturation (IVM 26h), and after 12h of in vitro fertilization (IVF 12h) respectively. Others were used to examine female pronucleus formation after 12h of culture in fertilization medium with the absence of sperm. The results showed that the percentage of CG completely release in the oocytes (IVM 24 and 26h) of toxicity group (41.2% and 39.9%) and vitrification group (41.7% and 51.7%) was significantly higher than that of control group (7.1% and 18.4%) (P <0.05). The ZP digestion duration in the oocytes (IVM 26h) of the toxicity group (435.6s) and vitrification group (422.3s) was longer than that of control group (381.6s) (P <0.05). The percentage of female pronucleus formation in toxicity group (58.7%) and vitrification group (63.9%) was higher than that (8.2%) of control group (P <0.05). The data above demonstrated that the VS containing DMSO and EG could parthenogenetically activate in vitro matured ovine oocytes, resulting in ZP hardening and decreased sperm penetration. [Copyright &y& Elsevier]

Abstract: The gene phaPAh, encoding the protein phasin that is associated with poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) granule of Aeromonas hydrophila 4AK4, was cloned and characterized. Recombinant strains harboring additional copies of the phasin gene (phaPAh) and the polyhydroxyalkanoate (PHA) synthase gene (phaCAh) accumulated PHBHHx copolyesters consisting of 21 mol% 3-hydroxyhexanoate (3HHx) as compared to 14 mol% 3HHx produced by wild type strain. The molecular weight of PHBHHx produced by the above recombinants was lower than that obtained from the wild type strain grown under similar conditions. Over-expression of phaPAh led to the production of more PHA granules but with reduced sizes. SDS–PAGE showed that PhaPAh was the predominant protein present in the PHBHHx granules. The RT-PCR results suggested that phasin PhaPAh, regulated phaCAh gene at the transcription level. Gene PhaPWe from Wautersia eutropha (formerly Ralstonia eutropha; encoding a 20kDa protein with low amino acid homology to the A. hydrophila 13kDa protein) cloned into A. hydrophila 4AK4 exhibited similar effects on PHBHHx production and PHBHHx composition. These data suggest that the phasins could represent a protein family possessing similar functions but different structures. [Copyright &y& Elsevier]

In vitro developmental competence of sheep oocytes is still relatively low. In this study, we investigated cathepsin B activity in sheep cumulus-oocyte complexes, the expression of cathepsin B and apoptosis rates in sheep cumulus cells, and the correlations between these indicies and in vitro developmental competence of sheep oocytes. The present result suggested that the active form of cathepsin B in cumulus-oocyte complexes was predominantly present in cumulus cells rather than oocytes. Cathepsin B activity in cumulus-oocyte complexes was strongly inhibited by cathepsin inhibitor E-64. RT-PCR analysis showed that cathepsin B expression in cumulus cells decreased during in vitro maturation. TUNEL staining and flow cytometry of cumulus cells showed that the apoptosis rate increased after in vitro maturation, and treatment with E-64 reduced both cathepsin B expression and apoptosis levels. Furthermore, E-64 treatment increased blastocyst rates of sheep. [ABSTRACT FROM AUTHOR]

Abstract: Although the success rate of sheep cloning remains extremely low, using a histone deacetylase (HDAC) inhibitor to increase histone acetylation in SCNT embryos has significantly enhanced developmental competence in several species. The objective was to determine whether HDAC inhibitors trichostatin A (TSA) and the novel inhibitor Scriptaid enhance cloning efficiency in sheep cumulus cell (passage 2) reconstructed embryos. In this study, 0.2 μmol/L Scriptaid yielded a high blastocyst development rate, almost twice that of the untreated group (25/103 [24.3%] vs. 12/101 [11.9%]; P < 0.05). Furthermore, 0.2 μmol/L Scriptaid was more effective than 0.05 μmol/L TSA in terms of the blastocyst percentage for cloned ovine embryos in vitro (17/66 [25.7%] vs. 11/65 [16.8%]; P < 0.05). Furthermore, treatment with Scriptaid increased acetylation (compared with the Control, P < 0.05) at lysine residue 12 of histone H4 (acH4K12) and lysine residue 9 of histone H3 (acH3K9) in one-, two-, four-, and eight-cell stages, as well as blastocyst stages, in cloned embryos. In conclusion, Scriptaid was more effective than TSA to enhance in vitro developmental competence in ovine SCNT embryos; furthermore, Scriptaid improved epigenetic status. [Copyright &y& Elsevier]