In angiosperms, the conversion of an egg cell into a zygote involves two sequential gametic processes: plasmogamy, the fusion of the plasma membranes of male and female gametes, and karyogamy, the fusion of the gametic nuclei. In this study, the nuclei and nuclear membranes of rice (Oryza sativa) gametes were fluorescently labeled using histones 2B-green fluorescent protein/red fluorescent prot...

The large, compactoocytenucleoli, sometimes referred toasnucleolus precursor bodies (NPBs), are essential for embryonic development in mammals; in their absence, the oocytes complete maturation and can be fertilized, but no nucleoli are formed in the zygote or embryo, leading to developmental failure. It has been convincingly documented that zygotes inherit the oocyte nucleolarmaterial and form...

BACKGROUND: The aim was to study zygote evaluation based on pronuclear morphology under the German embryo protection law, according to which only a maximum of three zygotes are allowed to be cultured for embryo transfer. METHODS: In this prospective multicentre study, a total of 512 treatment cycles was performed at 10 centres, between November 1999 and October 2000. Zygotes were classified int...

BACKGROUND Series of epigenetic events happen during preimplantation development. Therefore assistant reproduction techniques (ART) have the potential to disrupt epigenetic regulation during embryo development. The purpose of this study was to investigate whether defects in methylation patterns in blastocyst due to superovulation originate from abnormal expression of Dnmts. METHODS Low- (6 IU...

Let G1∨G2 denote the graph obtained from G1+G2 by adding new edges from each vertex of G1 to every vertex of G2. In this paper, the critical groups of the graphs Km ∨ Pn (n ≥ 4) and Pm ∨ Pn (m ≥ 4, n ≥ 5) are determined.

a vertex irregular total k-labeling of a graph g with vertex set v and edge set e is an assignment of positive integer labels {1, 2, ..., k} to both vertices and edges so that the weights calculated at vertices are distinct. the total vertex irregularity strength of g, denoted by tvs(g)is the minimum value of the largest label k over all such irregular assignment. in this paper, we study the to...

Chartrand et al. (2004) have given an upper bound for the nearly antipodal chromatic number ac′(Pn) as (n−2 2 ) +2 for n > 9 and have found the exact value of ac′(Pn) for n = 5, 6, 7, 8. Here we determine the exact values of ac′(Pn) for n > 8. They are 2p − 6p + 8 for n = 2p and 2p − 4p + 6 for n = 2p + 1. The exact value of the radio antipodal number ac(Pn) for the path Pn of order n has been ...

Water stress is one of the major abiotic stresses in agriculture worldwide. In order to assess photosynthesis response and grain yield of 25 wheat genotypes under water deficit (post-anthesis stress) conditions, a 2-year study (2010-12) was carried out as a split-plot arrangement using randomized complete block design with three replications. The most sensitive gas exchange variable to water de...