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The surface chemical properties of Y, Ti, Zr and Hf relevant to exoelectron and ion emission have been characterised by a range of techniques (XPS, UPS, AES, LEED, TDS, area-average and threshold φ). The chemisorptive properties of chlorine, bromine, sodium and rubidium are described, and (alkali + halogen) coadsorption has been studied also. Evolution of the trihalide corrosion layer is examined as are its decomposition properties; these features are rationalised in thermochemical and kinetic terms. In certain cases (Y/Na, Y/Rb, Hf/Rb) alkali adsorption results in a system work function equal to that of the bulk alkali at one-half monolayer coverage. Coadsorption of alkali and halogen leads to some particularly interesting observations. Substantial discrepancies (~ 1 eV) are found between the area-average work function \gf and the photoelectric threshold work function (φ∗); over certain coverage regimes, φ∗ actually decreases as \gf increases. This implies the formation of very low work function (< 2 eV) “exopatches”. Desorption from such systems does not occur via the alkali halide — in marked contrast with the behaviour of less electropositive substrates; this can be accounted for. The presence of halogens substantially increases the adsorption strength of the alkali. Models for the various surface phases are advanced and discussed.

This experiment was designed to examine the digestibilities of 3 commercially available equine feeds when fed with Bermudagrass hay, and the N and P waste associated with these types of concentrate feeds. The feeds used were a 12% protein pelleted feed produced by 3 different manufacturers. Nine mature Quarter Horse geldings were used in a 3 × 3 Latin square design. The apparent digestibilities for Ca were 39.02%, 25.47%, and 39.00% for feeds A, B, and C , respectively, with apparent Ca digestibilities of feeds A and C significantly higher (P

Bias-assisted hot filament chemical vapour deposition (HFCVD) and ion-assisted pulsed laser deposition (IA-PLD) have been employed to deposit carbon nitride films. Crystalline C-N films composed of α- and βC 3 N 4 , as well as some unpredicted C-N solids have been synthesized on Ni(100) substrates via HFCVD using a gas mixture of nitrogen and methane. The crystal constants of the α- and β-C 3 N 4 phases, obtained via X-ray diffraction, coincide well with those predicted theoretically; additionally, cone-shaped crystals are observed on the Si(100) substrates. Similarly, high density cone-shaped (Si)-C-N crystals have been obtained on Si(100) substrates via ion-assisted pulsed laser ablation of a carbon (graphite) target intersecting a nitrogen ion beam. Amorphous C-N films were also produced using this method.

Background Shigella dysentery is a relatively common illness and occasionally causes death, worldwide. Mild symptoms are self-limiting but in more severe cases, antibiotics are recommended for cure and preventing relapse. The antibiotics recommended are diverse, have regional differences in sensitivity, and have side effects. Objectives To evaluate the efficacy and safety of antibiotics for treating Shigella dysentery. Search strategy In June 2009 we identified all relevant trials from the following databases: Cochrane Infectious Diseases Group Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, issue 4), MEDLINE, EMBASE, LILACS and the metaRegister of Controlled Trials (mRCT). We also checked conference proceedings for relevant abstracts, and contacted researchers, organizations, and pharmaceutical companies. Selection criteria Randomized controlled trials of antibiotics for Shigella dysentery. Data collection and analysis Four authors, working in pairs, independently assessed trial eligibility, methodological quality, and extracted data. We calculated risk ratios (RR) with 95% confidence intervals (CI) for dichotomous data, and used the random-effects model for significant heterogeneity. We explored possible sources of heterogeneity, when present, in subgroup analyses of participant age and percentage of participants with confirmed Shigella infection. Main results Sixteen trials (1748 participants), spanning four decades and with differing sensitivity to Shigella isolates, met the inclusion criteria. Seven were judged to be at risk of bias due to inadequate allocation concealment or blinding, and 12 due to incomplete reporting of outcome data. Limited data from one three-armed trial of people with moderately severe illness suggest that antibiotics reduce the episodes of diarrhoea at follow-up (furazolidone versus no drug RR 0.21, 95% CI 0.09 to 0.48, 73 participants; cotrimoxazole versus no drug RR 0.30, 95% CI 0.15 to 0.59, 76 participants).There was insufficient evidence to consider any class of antibiotic superior in efficacy in treating Shigella dysentery, but heterogeneity for some comparisons limits confidence in the results. All the antibiotics studied were safe. There was inadequate evidence regarding the role of antibiotics in preventing relapses. Authors' conclusions Antibiotics reduce the duration of Shigella dysentery.Regularly updated local or regional antibiotic sensitivity patterns to different species and strains of Shigella are required to guide empiric therapy. More trials adhering to standard guidelines are required to evaluate the role of antibiotics in the treatment of severe forms of Shigella dysentery and in groups who are at high risk of complications.

Hypoparathyroidism commonly presents with paresthesias, fatigue, anxiety, muscle cramps and infrequently with seizures due to hypocalcaemia. Here, we present a case of 27-year-old adult female presenting with new onset convulsions who was subsequently diagnosed to have primary (congenital) hypoparathyroidism.

The catalytic mechanism of the enzyme carbonic anhydrase has recently been the subject of renewed debate. The generally accepted picture of the mechanism of the enzyme's action has been thrown into doubt by new evidence derived from spectroscopic techniques. In this paper some of the points of conflict are examined and the degree is assessed to which new evidence is incompatible with the previously held picture of CA action. Reinterpretations are put forward of the mechanisms of proton transfer between enzyme and solution and of the detailed mechanism of ligand displacement at the zinc ion. These show that the generally accepted picture of the mechanism of CA action is by no means disproved and remains plausible.