Evaluation of Whatsapp for Promoting Social Presence in a First Year Undergraduate Radiography Problem-Based Learning Group.

The article reports the findings of an analysis into student postings on a mobile instant messaging service (WhatsApp) established to develop social presence in a small group of first-year undergraduate radiography students. The analysis was carried out using a validated and reported tool specifically designed to identify categories of social presence, developed using the Community of Enquiry theoretical model. The students themselves undertook the analysis, which enhanced validity due to participant verification of findings. Six hundred posts (approximately 10% of the total year's messages) were analysed at key points in the first-year student journey. In conclusion, WhatsApp was able to provide students with a platform to demonstrate all the characteristics relevant for the development of social presence. In addition, its immediacy appeared to offer benefits over embedded social media platforms such as discussion boards.

(1)H NMR based metabolic profiling of day 2 spent embryo media correlates with implantation potential.

Morphological assessment is currently the primary technique for selection of viable embryos for uterine transfer during assisted reproductive techniques, however this method has limited predictive power. The objective of this study was to employ NMR based metabolic profiling analysis of spent embryo culture media to identify novel biomarkers of embryo viability and provide insight into the metabolism of a viable embryo. A total of 37 patients undergoing IVF/ICSI treatment were recruited and 58 media samples were collected from embryos that were transferred back to the uterus. 1H NMR spectra were acquired and analyzed resulting in the quantification of 12 metabolites in the media samples. Analysis of metabolite ratios revealed significant differences between those patients with positive (n = 27) and negative (n = 31) urinary ßhCG results. Some of the most biologically relevant differences include a 17% increase in the formate to glycine ratio and a 22% decrease in the citrate to alanine ratio in the spent embryo media from the positive pregnancy group. Overall, the results indicate that metabolic profiling may provide a means of identifying biomarkers that aid selection of viable embryos.

Thallophilic interactions and Tl-aryl π-interactions are competitive with cation-cation repulsion: [LTl2L]2+ dications as salts of weakly co-ordinating anions.

The synthesis and characterization by single-crystal X-ray diffraction of two thallium salts of the non-co-ordinating anion [B{3,5-(CF3)2C6H3}4] are reported. They possess Tl-Tl contacts supported by Tl-aryl interaction. This cation association overcomes both electrostatic repulsion and cation-anion size and charge matching considerations in the [LTl2L](2+) dications so formed.

Cadmium teratogenesis in the chick: period of vulnerability using the early chick culture method, and prevention by divalent cations.

Cadmium (Cd) is teratogenic in chick embryos following treatment in ovo or in shell-less culture. We investigated the ability of other divalent cations (Mn, Ni, Se, Mg and Ca) to influence the effects of Cd. As the proposed mechanism of protection of these ions is prevention of Cd influx by blocking or competing for Ca channels, we also assessed verapamil, a Ca-channel blocker. We used a new, completely ex ovo method, explanting the embryos onto an agar-albumen substrate (0.6% agar diluted 1:1 with thin albumen) to which test substances were added. Following 48-96 h incubation, chicks were explanted onto medium containing 7.5 microM Cd acetate or equimolar sodium acetate. Morphology and somite numbers were assessed at explantation, and again following 24h incubation on the culture media. In addition, 60-h embryos were explanted onto media containing various concentrations of the aforementioned agents, alone or in combination with 7.5 microM Cd. Chicks were vulnerable to Cd teratogenesis between Hamburger-Hamilton stages 13 and 18. Co-treatment with Se, Mn and Ni prevented malformation at 2x, 50 x and 100 x the molar dose of Cd, respectively. Ca, Mg and verapamil failed to protect. These results indicate that some, but not all, divalent cations protect against Cd malformation, but the mechanism of rescue remains unresolved.