SUMMARYDuring early embryo development the zona pellucida acts as a barrier against polyspermia and guarantees communication between blastomeres before and during compaction. However, the development of new technologies of embryo production such as "Handmade Cloning" demands removal of this membrane. The aim of this study was to determine the effect of zona pellucida removal on in vitro bovine embryo development. First, the consequences of zona pellucida removal was assessed by comparing the percentage of first cleavage, percentage of blastocysts and cell number among zona-included and zona-free embryos; either through the removal of the zona pellucida immediately after IVF or parthenogenesis. Embryo development was also evaluated when zona pellucida was removed before parthenogenesis. In a second set of experiments, the gene expression levels of BAX, BCL2, CASP3, CDH1, OCT4 and SOX2 were evaluated in zona-free and zona-included IVF-derived embryos. No significant differences were found in the percentage of first cleavage, percentage of blastocyst and cell number on IVF-embryos cultured with or without zona. Parthenogenetic embryos followed the same general pattern even when the zona pellucida was eliminated before activation; however there was a significant increase in the rate of first cleavage when the zona pellucida was removed after activation but this did not impact upon further development. Furthermore, no significant differences in gene expression level were found between zona-free and zona-included IVF-embryos for the studied genes. We concluded that the lack of zona pellucida did not affect the early development when an appropriate system is used for embryo culture to ensure blastomeric contact and normal compaction.

The crystal structure of N-methyl-1H-indole-2-carboxamide C 10 H 10 N 2 O was determined by single crystal X-ray diffraction. The structure can be described as consisting of an indole group and as substituent, linked at C2, the N-methylcarboxamide group. The molecular structure is essentially planar. The crystal packing results in N-H-O hydrogen bonds which join the molecules into centrosymmetric dimeric rings. The knowledge of the crystal structure allows a complete assignment of the 1 H and 13 C-NMR spectra. The N-methyl-1H-indole-2-carboxamide is the first indole derivative isolated from marine fungus.

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Polycrystalline Cu 2 ZnSnS 4-X Se X (X=1, 2, 3) compounds were synthesized by conventional solid-state reactions. The samples were characterized by powder X-ray diffraction (XRD), energy-dispersive X-ray analysis (SEM-EDS), Raman spectroscopy, diffuse reflectance UV-vis and Photoluminescence. All of phases crystallize in the tetragonal kesterite-type structure. The powder X-ray diffraction (XRD) patterns were indexed in the space group . No secondary phases were detected in XRD patterns. The results from diffuse reflectance show band gap between 1.26 -1.17 eV, when S is gradually replaced by Se. The PL spectrum of Cu 2 ZnSnS 4-x Se x phases shows nearly symmetrical band, which shifted linearly to the lower energy with increasing Se content. The selenized (CZTSSe) phases are promising candidates to be used as absorbing material in solar cells