Improving the design of a mCSCL Chinese character forming game with a distributed scaffolding design framework.

Appropriate design of collaborative learning activities for students using mobile devices can be supported by different forms of scaffolding provided by peers, by the teacher or by the technology. Building on prior studies in mCSCL (mobile computer-supported collaborative learning), we developed Chinese-PP, a novel in-class mobile synchronous collaborative learning game for constructing Chinese characters from components, with the unique characteristic of spontaneous small group formations. In this paper, we propose a distributed scaffolding design framework to guide us in examining and refining/revising the interplay among various forms of scaffolding in the learning model across various design-based research (DBR) cycles of our study on Chinese-PP in a primary school in Singapore. We believe a generalized scaffolding design framework has the potential to inform technology-enhanced learning research with a structure to support the iterative process of enacting and redesigning the socio-techno-pedagogical frameworks developed by individual research projects.

Control of the spread of viruses in a long-term care facility using hygiene protocols.

BACKGROUND: Approximately 50% of norovirus cases in the United States occur in long-term care facilities; many incidences of rotavirus, sapovirus, and adenovirus also occur. The primary objectives of this study were to demonstrate movement of pathogenic viruses through a long-term care facility and to determine the impact of a hygiene intervention on viral transmission. METHODS: The coliphage MS-2 was seeded onto a staff member's hands, and samples were collected after 4 hours from fomites and hands. After 3 consecutive days of sample collection, a 14-day hygiene intervention was implemented. Hand sanitizers, hand and face wipes, antiviral tissues, and a disinfectant spray were distributed to employees and residents. Seeding and sampling were repeated postintervention. RESULTS: Analysis of the pre- and postintervention data was performed using a Wilcoxon signed-rank test. Significant reductions in the spread of MS-2 on hands (P = .0002) and fomites (P = .04) were observed postintervention, with a >99% average reduction of virus recovered from both hands and fomites. CONCLUSION: Although MS-2 spread readily from hands to fomites and vice versa, the intervention reduced average MS-2 concentrations recovered from hands and fomites by up to 4 logs and also reduced the incidence of MS-2 recovery.

Screening sweetcorn for enhanced zeaxanthin concentration.

BACKGROUND: New varieties of fruits and vegetables, with higher carotenoid levels, are being developed to improve the potential health benefits to consumers. To assist the development of a new variety of high zeaxanthin sweetcorn, an analytical screening method was developed, including chromameter measurement of hue angle and optimized extraction for HPLC, and applied to 385 lines of a breeding population and six commercial varieties. RESULTS: Saponification had no effect on carotenoid extraction. In the breeding population, carotenoid levels had a wide range with the highest levels of zeaxanthin being 11.9 mg kg(-1) fresh weight, which was at least six times greater than the tested commercial varieties. The regression of hue angle versus zeaxanthin was described by the equation, hue angle = 76.16 + 4.50 x exp(-0.24 x zeaxanthin) + 11.73 x exp(-0.24 x zeaxanthin), r(2) of 0.59. The top 6% of lines, with regards to zeaxanthin (zeaxanthin + beta-cryptoxanthin + beta-carotene) and total carotenoids, all had hue angles

HBcAg-specific CD4+CD25+ regulatory T cells modulate immune tolerance and acute exacerbation on the natural history of chronic hepatitis B virus infection.

Acute exacerbations (AEs) of chronic hepatitis B (CH-B) are accompanied by increased T cell responses to hepatitis B core and e antigens (HBcAg/HBeAg). Why patients are immunotolerant (IT) to the virus and why AEs occur spontaneously on the immunoactive phase remain unclear. The role of HBcAg-specific CD4(+)CD25(+) regulatory T (T(reg)) cells in AE and IT phases was investigated in this study. The SYFPEITHI scoring system was employed to predict MHC class II-restricted epitope peptides on HBcAg overlapping with HBeAg that were used for T(reg)-cell cloning and for the construction of MHC class II tetramers to measure T(reg) cell frequencies (T(reg) f). The results showed that HBcAg-specific T(reg) f declined during AE accompanied by increased HBcAg peptide-specific cytotoxic T lymphocyte frequencies. Predominant Foxp3-expressing T(reg) cell clones were generated from patients on the immune tolerance phase, while the majority of Th1 clones were obtained from patients on the immunoactive phase. T(reg) cells from liver and peripheral blood of CH-B patients express CD152 and PD1 antigens that exhibit suppression on PBMCs proliferation to HBcAg. These data suggest that HBcAg peptide-specific T(reg) cells modulate the IT phase, and that their decline may account for the spontaneous AEs on the natural history of chronic hepatitis B virus infection.