Type Ia supernovae are destructive explosions of carbon oxygen white dwarfs. Although they are used empirically to measure cosmological distances, the nature of their progenitors remains mysterious, ...One of the leading progenitor models, called the single degenerate channel, hypothesizes that a white dwarf accretes matter from a companion star and the resulting increase in its central pressure and temperature ignites thermonuclear explosion. Here we report observations of strong but declining ultraviolet emission from a Type Ia supernova within four days of its explosion. This emission is consistent with theoretical expectations of collision between material ejected by the supernova and a companion star, and therefore provides evidence that some Type Ia supernovae arise from the single degenerate channel.
It has been established that the antimicrobial activity of lactoferrin towards Escherichia coli is enhanced by a direct contact between the protein and the microbial cell and that, in the case of E. ...coli K-12 strains, an antibacterial activity of lactoferrin unrelated to iron withdrawal is present. Evidence is now reported that lactoferrin binds to surface structures expressed in E. coli K-12 strains grown in either an "excess" or "stress" of iron. Under the experimental conditions used, lactoferrin binding both in the apo and in the iron-saturated form yields a maximum of 1.6 X 10(5) bound molecules/E. coli K-12 cell; the amount of lactoferrin bound does not depend on the expression of the iron-regulated outer membrane proteins. In contrast, lactoferrin does not bind to E. coli clinical isolates. Apo-lactoferrin (at 500 micrograms/ml in a chemically defined medium) inhibits the growth of E. coli K-12 strains but not of clinical isolates. These findings suggest that the antibacterial activity of the protein could be associated to its binding to the cell surface.
ESO Messenger 155, (2014), 29-32 The VISTA Variables in the V\'ia L\'actea (VVV) survey is one of six public
ESO surveys, and is now in its 4th year of observing. Although far from being
complete, ...the VVV survey has already delivered many results, some directly
connected to the intended science goals (detection of variables stars,
microlensing events, new star clusters), others concerning more exotic objects,
e.g. novae. Now, at the end of the fourth observing period, and comprising
roughly 50% of the proposed observations, the actual status of the survey, as
well some of the results based on the VVV data, are presented.
A operacao envolve pouco dinheiro vivo e uma sofisticada engenharia societaria. Foi chamada de "aquisicao originaria". A Tenda vai incorporar a companhia da Gafisa dedicada a baixa renda, chamada ...Fit. Novas acoes emitidas pela Tenda, num total de 240,4 milhoes de papeis, serao entregues a Gafisa, que assumira 60% da companhia ao fim do processo. Ou seja, se tornara a socia majoritaria e controladora da nova empresa - soma de Tenda e Fit. Os atuais donos da Tenda, que tem 51% da empresa, ficarao com 20,3% apos o negocio. Os minoritarios dispersos na bolsa, que hoje detem 49% das acoes, terao 19,7%.
The aim of this preliminary study conducted in a few cases was the retrospective evaluation of the effects of laparoscopic Nissen fundoplication on oesophageal intestinal metaplasia. Seventy-seven ...patients with hiatal hernia underwent digital videofluorography, endoscopy with biopsies, motility studies and 24-h oesophageal pH-monitoring. On the basis of the results of the diagnostic procedures and considering the patients' ages and response to proton-pump inhibitor treatment, 8 patients underwent laparoscopic Nissen fundoplication; in 5 cases intestinal metaplasia was present at histopathological examination. Two of these had Barrett's oesophagus at endoscopy and intestinal metaplasia was associated with low-grade dysplasia in both at histology; the other 3 did not present a columnar mucosa at endoscopy and 1 had low-grade dysplasia. In all 5 patients, at 1 year postoperative histopathological control, disappearance or decrease of metaplastic epithelium and regression of dysplasia were noted, with excellent results in terms of reflux symptoms at clinical control. On the basis of these preliminary data, it is our opinion that antireflux surgery is not only a suitable treatment in the management of Barrett's oesophagus but also has a favourable effect on intestinal metaplasia regression when a normal oesophageal mucosa is present.
The aim of the study was to evaluate the correlation between hiatal hernia and gastro-oesophageal reflux and related histological abnormalities in patients without endoscopic oesophagitis. A ...consecutive series of 78 patients with a history of gastro-oesophageal reflux symptoms and hiatal hernia, as defined by videofluorography combined with a water siphon test, underwent oesophagogastroduodenoscopy and multiple biopsies. Hiatal hernia was confirmed endoscopically in 99% of cases. The water siphon test was positive for reflux in 72% of cases. At endoscopy 42% of patients had oesophagitis and/or Barrett's oesophagus and 58% had no lesions. In the group without endoscopic lesions, at histology oesophagitis-related alterations were found in 98% and intestinal metaplasia in 27%. In conclusion, this study shows that symptomatic gastro-oesophageal reflux patients with radiologically defined hiatal hernia should undergo endoscopy with multiple biopsies above the squamocolumnar junction, even when endoscopy is normal. This is in order to detect histological gastro-oesophageal-reflux-related alterations, above all, when a positive water siphon test is also present, owing to its known correlation with intestinal metaplasia.
The VISTA Variables in the Vía Láctea (VVV) survey is one of six public ESO surveys, and is now in its 4th year of observing. Although far from being complete, the VVV survey has already delivered ...many results, some directly connected to the intended science goals (detection of variables stars, microlensing events, new star clusters), others concerning more exotic objects, e.g. novae. Now, at the end of the fourth observing period, and comprising roughly 50% of the proposed observations, the actual status of the survey, as well some of the results based on the VVV data, are presented.
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