The study showed that landscapes dominated by crops are more fragmented than landscapes dominated by pastures. These crop-dominated landscapes also presented a smaller number of fragments that could maintain populations of threatened mammal species in Cerrado. Regions with more preserved natural areas are in the northeast of Goias, where there are rough relief and soil unsuitable for agriculture. Our results indicate that croplands generate a landscape structure more damaging for the conservation of biodiversity in the Cerrado biome. Otherwise,
they support the importance to preserve natural remnants, even in areas occupied by agriculture, mainly due to its potential to maintain
ecosystem check details services, and suggest that landscapes dominated by pastures should have more current value for conservation, since they showed larger fragments. (C) 2009 Elsevier Ltd. All rights reserved.”
“We report measurement of electron-emission yield (EEY) under the impact of electrons on materials of Hall-effect-thruster (HET) interest: BN, BN-SiO(2), and Al(2)O(3). The effects of the material aging (under electron irradiation) on the yield of BN and Al(2)O(3) learn more are investigated. The EEY of BN grows with electron exposure, whereas that of Al(2)O(3) reduces. A simple analysis of our experimental results indicates that these variations are most likely because of surface and near surface composition changes caused by the electron beam. The representativeness of EEY measurements on ceramics that Selleck Bafilomycin A1 have not suffered from the specific environment of a HET (ion and electron bombardment) is discussed. (C) 2011 American Institute of Physics. [doi:10.1063/1.3653820]“
“The introduction of prostate-specific antigen (PSA) for prostate
cancer screening in the late 1980s led to an epidemic of prostate cancer, particularly in developed countries. However, the first valid reports from randomized controlled trials on the efficacy of screening were not published until 2009. Men in the screening group in the European Randomized Study of Screening for Prostate Cancer were 20% less likely than those in the control group to die from prostate cancer. The absolute difference was only 0.7/1000, implying that over 1400 men needed to be screened to prevent one prostate cancer death. Screening was also associated with a 70% increased risk for being diagnosed with prostate cancer. The American Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial found no survival benefit for screening. Results were not conclusive because a substantial proportion of study subjects had previously undergone PSA testing, over half of the control group had PSA testing, follow-up was relatively short, and fewer than 100 subjects died from prostate cancer.