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“A major goal of evolutionary biology is to identify the causes of diversification and to ascertain why some evolutionary lineages are especially diverse. Evolutionary biologists have long speculated that polyphenism-where a single genome produces alternative phenotypes in response to different environmental stimuli-facilitates speciation, especially when these alternative phenotypes Staurosporine order differ in resource or habitat use, i.e. resource polyphenism. Here, we present a series of replicated sister-group comparisons showing that fishes and amphibian clades in which resource

polyphenism has evolved are more species rich, and have broader geographical ranges, than closely related clades lacking resource polyphenism. Resource polyphenism may promote diversification by facilitating each of the different stages of the speciation process (isolation, divergence, reproductive isolation) and/or

by reducing a lineage’s risk of extinction. Generally, resource polyphenism may play a key role in fostering diversity, and species in which resource polyphenism has evolved may be predisposed to diversify.”
“In weakly absorbing materials such as polymers and soft tissue, x-ray phase sensitive imaging methods can provide substantially enhanced contrast compared to classical, absorption based radiography. For specific applications, the latter can be applied in a dual energy scheme that helps to identify, discriminate and/or quantify materials. In this paper, we report on a new method that combines the idea of dual energy with x-ray VX-809 phase contrast imaging and thus provides P5091 cell line material sensitivity among poor absorbers. The dual energy modality cannot be applied in common phase contrast imaging

schemes because of their demand for limited bandwidth or even monochromatic x-ray sources. Our new interferometric method based on diffraction gratings can overcome this shortcoming and thus simultaneously deliver x-ray phase contrast images for two distinct x-ray energy intervals. It has been shown that high quality images can be obtained with the dual energy phase setup. Energy spectra with 40 kV and 70 kV were applied to obtain low- and high-energy images, respectively. Furthermore, an estimation of the effective energy in the image formation process for absorption and phase contrast was experimentally determined. Examples are shown for which the dual energy phase contrast modality delivers complementary information on material composition when compared with the conventional dual energy scheme. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3512871]“
“Urological complications contribute to morbidity and graft loss after kidney transplantation. Aim of this study was to assess the role of revisional surgery on patient outcome. From 1997 to 2007, 887 patients underwent kidney transplantation in our institution. Clinical data of patients with urological complications were analyzed. Ureteral complications were observed in 50 of 887 (5.