A few studies have been recently presented for the existence of oxygen in diamond, for example, the N3 EPR centres have been theoretically and experimentally assigned the model made up from complex of substitutional nitrogen and substitutional oxygen as nearest neighbours. We present ab initio calculations of substitutional oxygen in diamond in terms of stability, electronic structures, geometry and hyperfine interaction and show that substitutional oxygen with C$_{2v}\,$, $S=1$ is the ground state configuration. We find that oxygen produces either a donor or acceptor level depending on the position of the Fermi level. arabic 8 English 59
Khaled Mohamed Ramadan Etmimi(12-2015)

حل مسالة القيمة الذاتية للنمطين الكهربي TE و المغناطيسي TM المستعرضين لالفالم الرقيقة دورية الطبقات. arabic 241 English 4
عبدالسلام إمحمد إبراهيم ابوبكر, عبدالعزيز أحمد الكويلاني, علي امحمد بشير المجاهد(7-2019)

Environmental toxicants such as chemicals, heavy metals, and pesticides have been shown to promote transgenerational inheritance of abnormal phenotypes and/or diseases to multiple subsequent generations following parental and/ or ancestral exposures. This study was designed to examine the potential transgenerational action of the environmental toxicant trichloroethane (TCE) on transmission of liver abnormality, and to elucidate the molecular etiology of hepatocyte cell damage. A total of thirty two healthy immature female albino mice were randomly divided into three equal groups as follows: a sham group, which did not receive any treatment; a vehicle group, which received corn oil alone, and TCE treated group (3 weeks, 100 μg/kg i.p., every 4th day). The F0 and F1 generation control and TCE populations were sacrificed at the age of four months, and various abnormalities histpathologically investigated. Cell death and oxidative stress indices were also measured. The present study provides experimental evidence for the inheritance of environmentally induced liver abnormalities in mice. The results of this study show that exposure to the TCE promoted adult onset liver abnormalities in F0 female mice as well as unexposed F1 generation offspring. It is the first study to report a transgenerational liver abnormalities in the F1 generation mice through maternal line prior to gestation. This finding was based on careful evaluation of liver histopathological abnormalities, apoptosis of hepatocytes, and measurements of oxidative stress biomarkers (lipid peroxidation, protein carbonylation, and nitric oxide) in control and TCE populations. There was an increase in liver histopathological abnormalities, cell death, and oxidative lipid damage in F0 and F1 hepatic tissues of TCE treated group. In conclusion, this study showed that the biological and health impacts of environmental toxicant TCE do not end in maternal adults, but are passed on to offspring generations. Hence, linking observed liver abnormality in the offspring to environmental exposure of their parental line. This study also illustrated that oxidative stress and apoptosis appear to be a molecular component of the hepatocyte cell injury.
Mohamed A. Al-Griw , Soad A. Treesh, Rabia O. Alghazeer, Sassia O. Regeai (7-2017)