Influence of aging and dilution on the crystallization of silicate-1

The correlation between the formation of colloidal aggregates and the crystallization of silicalite-l from a clear solution has been investigated with in situ combined small-angle X-ray scattering and wide-angle X-ray scattering, and in situ ultra- small-angle X-ray scattering using synchrotron radiation. Increasing the aging time at room temperature of the synthesis mixture prior to heating to the reaction temperature reduced the induction period and increased the crystal growth rate without affecting the formation of colloidal aggregates. Dilution of the synthesis mixtures did not influence the nucleation and crystal growth rate, and did not affect the formation of colloidal aggregate

ENOBIO - First tests of a dry electrophysiology electrode using carbon nanotubes

We describe the development and first tests of Enobio, a dry electrode sensor concept for biopotential applications. In the proposed electrodes, the tip of the electrode is covered with a forest of multi-walled CNTs that can be coated with Ag/AgCl to provide ionic-electronic transduction. The CNT brush-like structure is to penetrate the outer layers of the skin improving electrical contact as well as increae the contact surface area. In this paper, we report the results of the first tests of this concept -- immersion on saline solution and pig skin signal detection. These indicate performance on a par with state of the art research-oriented wet electrodes.Comment: Submitted and accepted at the 28th IEEE EMBS International Conference, New York City, August 31st-September 3rd, 2006. Figures updated with proper filtering and averagin

Prevalencia de caries dental en niños entre 1996–2000

Objectives This study was carried out to assess whether delaying umbilical cord clamping is effective in improving the haematological status of term infants living in a malaria-endemic area, and whether this is associated with complications in infants and mothers. Metyhods We randomly assigned women delivering term babies in Mpongwe Mission Hospital, Zambia, to delayed cord clamping (DCC, n = 46) or immediate cord clamping (controls, n = 45) and followed their infants on a bi-monthly basis until the age of 6 months. We compared the haemoglobin (Hb) change from cord values and the proportion of anaemic infants. Secondary outcomes related to infant and maternal safety. Results Throughout the observation period infant Hb levels in both groups declined, but more rapidly in controls than in the DCC group [difference in Hb change from baseline at 4 months 1.1 g/dl, 95% confidence interval (CI) 0.2; 2.1]. By 6 months, this difference had disappeared (0.0 g/dl, 95% CI -0.9; 0.8). The odds ratio for iron deficiency anaemia in the DCC group at 4 months was 0.3 (95% CI 0.1; 1.0), but no differences were found between the groups at 6 months. No adverse events were seen in infants and mothers. Conclusion Our findings indicate that DCC could help improve the haematological status of term infants living in a malaria-endemic region at 4 months of age. However, the beneficial haematological effect disappeared by 6 months. This simple, free and safe delivery procedure might offer a strategy to reduce early infant anaemia risk, when other interventions are not yet feasible

The lifespan of parents of diabetic subjects

Resumen temporalmente no disponible. La presente obra no cuenta con resumen provisto por el autor.Fil. Pérez, Moira. Universidad de Buenos Aires. Facultas de Filosofía y Letra