985 resultados para 23-223
Resumo:
Galactic cosmic rays (GCRs) are extremely difficult to shield against and pose one of the most severe long-term hazards for human exploration of space. The recent solar minimum between solar cycles 23 and 24 shows a prolonged period of reduced solar activity and low interplanetary magnetic field strengths. As a result, the modulation of GCRs is very weak, and the fluxes of GCRs are near their highest levels in the last 25 years in the fall of 2009. Here we explore the dose rates of GCRs in the current prolonged solar minimum and make predictions for the Lunar Reconnaissance Orbiter (LRO) Cosmic Ray Telescope for the Effects of Radiation (CRaTER), which is now measuring GCRs in the lunar environment. Our results confirm the weak modulation of GCRs leading to the largest dose rates seen in the last 25 years over a prolonged period of little solar activity.
Resumo:
The present paper summarizes the consensus views of a group of 9 European clinicians and scientists on the current state of scientific knowledge on probiotics, covering those areas where there is substantial evidence for beneficial effects and those where the evidence base is poor or inconsistent. There was general agreement that probiotic effects were species and often strain specific. The experts agreed that some probiotics were effective in reducing the incidence and duration of rotavirus diarrhoea in infants, antibiotic-associated diarrhoea in adults and, for certain probiotics, Clostridium difficile infections. Some probiotics are associated with symptomatic improvements in irritable bowel syndrome and alleviation of digestive discomfort. Probiotics can reduce the frequency and severity of necrotizing enterocolitis in premature infants and have been shown to regulate intestinal immunity. Several other clinical effects of probiotics, including their role in inflammatory bowel disease, atopic dermatitis, respiratory or genito-urinary infections or H.pylori adjuvant treatment were thought promising but inconsistent.