[en] The vibration and electronic vibration spectra of Di-uranyl sufate have been studied. Analysis of the shifts of the structural group vibration frequencies due to their interaction with crystal lattice, has made it possible to determine the spectral regions exhibiting normal vibrations of sulfate ions that differ in spatial structure and in the type of coordination with uranyl ion. The O-O line splitting at low temperature electronic vibrational spectra could be used as a basic for the interpretation of these spectra using a multicenter model. These mechanisms are of interest for further development of the theory of complex compounds. The changes observed in the structure of tetrahedral sulfate ions upon variations in chemical compositions of a substance could be used for studying the processes of lattice reorganization and elucidation of the nature of phase transitions in ferroelectric crystals containing such a group. (author)

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[en] A potential double layer was formed in front of a positively biased substrate in pure SF₆ discharge plasma while a potential dip was observed in the electropositive plasma and decreased with the addition of SF₆ gas. In low electron temperature plasma governed by a magnetic filter, the positive biased substrate only reduce the plasma potential without remarkable change of the sheath potential structure. (author)

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[en] To determine the influence of tobacco exposure in the development of metabolic syndrome (MS) in the adult Saudi population. Six hundred and sixty-four adults (305 males and 359 females) aged 25-70 years were included in this cross-sectional study conducted at the King Abdul Aziz University Hospital, between June 2006 and May 2007. We classified the participants into non-smokers, smokers, and ex-smokers (defined as complete cessation for 1-2 years). All subjects were screened for the presence of MS using the modified American Heart Association/National Heart, Lung and Blood Institute (AHA/NHLBI), International Diabetes Federation (IDF) and World Health Organization (WHO) definitions. Metabolic syndrome was highest among ex-smokers regardless of definition used. Relative risk for ex-smokers (95% CI: 2.23, 1.06-4.73) was more than twice in harboring MS as compared to non-smokers (95% CI: 2.78, 1.57-4.92) (p=0.009). Acute post-cessation smoking is a strong predictor for MS among male and female Arabs. Smoking cessation programs should include a disciplined lifestyle and dietary intervention to counteract the MS-augmenting side-effect of smoking cessation. (author)

[en] From the emergence of different definitions of metabolic syndrome (MS) we aim to determine the prevalence of such a condition among hypertensive Saudi population and to identify which definition can best assess the risk of hyperhomocysteinemia, coronary heart disease (CHD), and diabetes mellitus. In this cross-sectional study, we studied 581 hypertensive Saudis, aged 21-70, at the King Abdul-Aziz University Hospital, from June 2005 to December 2005 Each participant completed the questionnaire and underwent a complete physical examination. Metabolic parameters were measured using routine laboratory procedures and homocysteine using HPLC by the electrochemical detection method. According to the International Diabetes Federation (IDF) definition we diagnosed 222 males and 256 females. There is an increased risk for hyperhomocystenemia using the Adult Treatment Panel III (ATPIII) guidelines (odds ratio [OR] 3.30, 95% confidence interval [CI] 0.87-12.56; p=0.08) compared to IDF (OR 0.59, CI 0.17-2.10; p=0.41) and WHO (OR 0.45, CI 0.16-1.25; p=0.12); increased risk for probable CHD in patients with MS by WHO (OR 2.17, CI 1.11-4.25; p=0.02) compared to ATPIII (OR 2.14, CI 1.05-4.35; p=0.035) and IDF (OR 0.81, CI 0.37-1.78; p=0.6); risk of DM is highest with IDF (OR 13.07, CI 1.66-102.94; p=0.015). There is a high prevalence of MS among hypertensive Saudis regardless of definition used; it is most prevalent using the IDF definition as well as the risk for diabetes Patients diagnosed with ATPIII guidelines have greater risk of hyperhomocysteinemia. We recommend the WHO definition for Arabs since it predicts increased risk for CHD. (author)

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[en] This study aims to determine of concentration of three trace heavy metals (Cd, Pb, Hg) in the marine shore sediments collected from nine sites of Alkabeer Aljnouby river estuary during the period (5/7/2004-29/6/2005), using cold vapor technique for the determination of Hg and (ETA-AAS) for Cd and Pb. Results revealed that the medians accumulation in the marine shore sediments at all studied sites ranged between (3.46-16.60 μg/g dry wt.), (nd-0.085 μg/g dry wt.) and (nd-0.096 μg/g dry wt.) for Pb, Cd, Hg respectively. The results showed that the concentrations of Pb at all studied sites were higher than the concentrations of Cd and Hg. The concentrations of Cd values in the sediment samples were related nearby at all studied sites during the study period, while the concentrations of Hg were decreased in summer 2004 and increased in other seasons.The study of relationships between the values of concentration of the studied element concentrations in the sediment samples indicates no obvious correlation between the studied sites.(author)