Tea and coffee consumption in relation to vitamin D and calcium levels in Saudi adolescents

ABSTRACT: BACKGROUND: Coffee and tea consumption was hypothesized to interact with variants of vitamin D-receptor polymorphisms, but limited evidence exists. Here we determine for the first time whether increased coffee and tea consumption affects circulating levels of 25-hydroxyvitamin D in a cohort of Saudi adolescents. METHODS: A total of 330 randomly selected Saudi adolescents were included. Anthropometrics were recorded and fasting blood samples were analyzed for routine analysis of fasting glucose, lipid levels, calcium, albumin and phosphorous. Frequency of coffee and tea intake was noted. 25-hydroxyvitamin D levels were measured using enzyme-linked immunosorbent assays. RESULTS: Improved lipid profiles were observed in both boys and girls, as demonstrated by increased levels of HDL-cholesterol, even after controlling for age and BMI, among those consuming 9--12 cups of coffee/week. Vitamin D levels were significantly highest among those consuming 9--12 cups of tea/week in all subjects (p-value 0.009) independent of age, gender, BMI, physical activity and sun exposure. CONCLUSION: This study suggests a link between tea consumption and vitamin D levels in a cohort of Saudi adolescents, independent of age, BMI, gender, physical activity and sun exposure. These findings should be confirmed prospectively.     

Modeling of nucleate boiling heat transfer under an impinging free jet

A model using an analytical/empirical approach has been developed to predict the rate of heat transfer in the stagnation region of a planar jet impinging on a horizontal flat surface. The model has been developed based on the hypothesis that bubble-induced mixing would result in enhanced or additional diffusivity. The additional diffusivity has been included in the diffusion term of the conservation equations. The value of the effective diffusivity has been correlated with jet parameters (velocity and temperature) and surface temperature using experimental data. The important aspects of the bubble dynamics (generation frequency and average bubble diameter) have been acquired using high-speed imaging and an intrusive optical probe. The applicability of the proposed model has been investigated under conditions of partial and fully-developed nucleate boiling. Experiments have been carried out using water at atmospheric pressure, mass flux in the range of 388–1649 kg/m² s, degree of sub-cooling in the range of 10–28 °C, and surface temperature in the range of 75–120 °C. Results showed that the proposed model is able to predict the surface heat flux with reasonable accuracy (+30% and ?15%).     

E-health support services based on service-oriented architecture

This paper discusses an experimental scenario for an e-health monitoring system (EHMS) that uses a service-oriented architecture (SOA) as a model for deploying discovering, integrating, implementing, managing, and invoking e-health services. Such a model could help the healthcare industry to develop cost efficient and dependable healthcare services.     

Improvement of some pharmaceutical properties of drugs by cyclodextrin complexation. 4. Chlorpromazine hydrochloride

This study is a retrospective review of admissions, discharge records and blood culture results of neonates admitted to the Neonatal Intensive Care Unit of Korle Bu Teaching Hospital in Accra, from the first of January 1991 to the 31st of December 1992. During this two year period there were 443 positive blood cultures. Ninety percent of the blood cultures were from babies born in Korle Bu Teaching Hospital, thus making the incidence of neonatal bacteraemia 22.2 per 1000 live births. The overall mortality rate was 37.2%. Gram negative bacteria accounted for 70.9% and Gram positive bacteria for 29.1% of all neonatal bacteraemia. The most common isolates were Enterobacter species 29.6%; Streptococcus faecalis 14.4%; Staphylococcus aureus 10.8%; Acinetobacter species 9.5%; Klebsiella species 9% and Escherichia coli 8.8%. It is concluded that the incidence of neonatal bacterial sepsis is high in our hospital and is associated with a very high mortality rate. There is thus an urgent need to institute appropriate preventive and therapeutic measures.     

Studies in the use of recombined milk for the manufacture of ras cheese

Whey was employed as a reconstituting medium for dried milk used for cheese making.Ras cheese was made from fresh milk; whey was collected and dried skim milk was used to prepare a reconstituted milk with 20% total solids. Ras cheese was made from it and this process was repeated a further three times.The addition of whey was beneficial in reducing, by 50%, the time necessary to raise the acidity of milk to make it suitable for rennet action. The time necessary to make it suitable for whey removal was also reduced by 50%. Consequently, the time required for pressing was only 8 h, instead of 16 h. Generally, the use of whey is considered to be a better process for Ras cheese making. In addition to the utilisation of whey, it produced a good and acceptable cheese. The cheese was manufactured within a shorter time than cheese made with fresh milk.     

Reactions of saturated hydrocarbons I. Oxidation of isoparaffins by chromic acid

Measurements of the rate of reduction of chromium(VI) oxide in acetic acid–acetic anhydride solution by 2-methyl-pentane, 3-methylpentane, 2,3-dimethylbutane and 2,4-dimethylpentane show that the initial rate depends on the number and nature of carbon atoms in the hydrocarbon. When steric or other interaction effects prevail between adjacent atoms or groups in the molecule, these effects also influence the rate. The values obtained for the oxidation rates agree with those calculated from a proposed expression (Rn_p+R'n_s+R'n_t)/(n_p+n_s+n_t) based on the formula of Chambers & Ubbelohde.     

Structural Diversity and Defensive Properties of Norditerpenoid Alkaloids

We have tested the insect antifeedant and toxic activity of 43 norditerpenoid alkaloids on Spodoptera littoralis and Leptinotarsa decemlineata including eserine (physostigmine), anabasine, and atropine. Antifeedant effects of the test compounds were structure- and species-dependent. The most active antifeedants to L. decemlineata were 1,14-diacetylcardiopetaline (9) and 18-hydroxy- 14-O-methylgadesine (33), followed by 8-O-methylconsolarine (12), 14-O-acetyldelectinine (27), karakoline (7), cardiopetaline (8), 18-O-demethylpubescenine (13), 14-O-acetyldeltatsine (18), takaosamine (21), ajadine (24), and 8-O-methylcolumbianine (6) (EC50 < 1 microg/cm2). This insect showed a moderate response to atropine. S. littoralis had the strongest antifeedant response to 24, 18, 14-O-acetyldelcosine (19), and delphatine (29) (EC50 < 3 microg/cm2). None of the model substances affected the feeding behavior of this insect. The most toxic compound to L. decemlineata was aconitine (1), followed by cardiopetalidine (10) (% mortality > 60), 14-deacetylpubescenine (14), 18-O-benzoyl-18-O-demethyl-14-O-deacetylpubescenine (17), 14-O-acetyldelcosine (19), 14-deacetylajadine (25) and methyllycaconitine (30) (% mortality > 45). Orally injected S. littoralis larvae were negatively affected by 1, cardiopetaline (8), 10, 1,14-O-acetylcardiopetalidina (11), 12, 14, 1,18-O-diacetyl-19-oxo-gigactonine (41), olivimine (43), and eserine in varying degrees. Their antifeedant or insecticidal potencies did not parallel their reported nAChR binding activity, but did correlate with the agonist/antagonist insecticidal/antifeedant model proposed for nicotininc insecticides. A few compounds [14, tuguaconitine (38), 14-demethyldelboxine (40), 19, dehydrodelsoline (36), 18-O-demethylpubescenine (13), 41, 9, and delcosine (23)] had selective cytotoxic effects to ward insect-derived Sf9 cells. None were cytotoxic to mammalian CHO cells and none increased Trypanosoma cruzi mortality. The selective cytotoxic effects of some structures indicate that they can act on biological targets other than neuroreceptors.     

Effects of postchill application of acidified sodium chlorite to control Campylobacter spp. and Escherichia coli on commercial broiler carcasses

Experiments were performed to assess the reduction of Campylobacter spp. and Escherichia coli in commercial broiler carcasses by postchill dip applications of acidified sodium chlorite. Carcass rinses were collected before the inside-outside-bird washer (IOBW), post-IOBW, postchill, and after the postchill application of acidified sodium chlorite. Prevalence and counts of Campylobacter spp. and E. coli were determined. The mean values for Campylobacter spp. and E. coli counts differed significantly at sampling sites. The IOBW reduced the bacterial counts significantly in only one experiment. The chiller reduced Campylobacter counts significantly in both experiments but failed to significantly reduce the counts of E. coli in one experiment. No major reduction in the prevalence after enrichment for Campylobacter spp. was detected post-IOBW or postchill. However, a significant reduction in Campylobacter spp. and in E. coli counts and Campylobacter spp. prevalence was seen after the postchill application of acidified sodium chlorite. These results demonstrate that the antimicrobial effect of acidified sodium chlorite applied postchill may be used to significantly reduce Campylobacter spp. and E. coli in commercial broiler carcasses. Postchill systems may eventually be used in different applications, such as mist, spray, or bath, which could be applied closer to the final stages in processing.     

A high-performance computing method for data allocation in distributed database systems

Enhancing the performance of the DDBs (Distributed Database system) can be done by speeding up the computation of the data allocation, leading to higher speed allocation decisions and resulting in smaller data redundancy and shorter processing time. This paper deals with an integrated method for grouping the distributed sites into clusters and customizing the database fragments allocation to the clusters and their sites. We design a high speed clustering and allocating method to determine which fragments would be allocated to which cluster and site so as to maintain data availability and a constant systemic reliability, and evaluate the performance achieved by this method and demonstrate its efficiency by means of tabular and graphical representation. We tested our method over different network sites and found it reduces the data transferred between the sites during the execution time, minimizes the communication cost needed for processing applications, and handles the database queries and meets their future needs.     

Volume Changes of Iron Oxide Compacts under Isothermal Reduction Conditions

Compacts made from chemically grade Fe₂O₃ were fired at 1473K for 6 hrs. The fired compacts were isothermally reduced either by hydrogen or carbon monoxide at 1073–1373K. The O₂ weight‐loss resulting from the reduction process was continuously recorded as a function of time using TGA technique, whereas the volume change at different reduction conditions was measured by displacement method. Porosity measurements, microscopic examination and X‐ray diffraction analysis were used to characterize the fired and reduced products. The rate of reduction at both the initial and final stages was increased with temperature. The reduction mechanism deduced from the correlations between apparent activation energy values, structure of partially reduced compacts and application of gas‐solid reaction models revealed the reduction rate (dr/dt) at both the initial and final stages. At early stages, the reduction was controlled by a combined effect of gaseous diffusion and interfacial chemical reaction mechanism, while at the final stages the interfacial chemical reaction was the rate determining step. In H₂ reduction, maximum swelling (80%) was obtained at 1373K, which was attributed to the formation of metallic iron plates. In CO reduction, catastrophic swelling (255%) was obtained at 1198K due to the formation of metallic iron plates and whiskers.