In Chile, two predatory crab species (Acanthocyclus gayi and Acanthocyclus hassleri) coexist in the intertidal zone. Both settle preferentially in mussel beds, but adults show remarkable spatial segregation, apparently as a result of asymmetric competition for refuges. Although early recruits of A. gayi are an order of magnitude more abundant than A. hassleri, late juveniles are similarly abundant. Recruits of A. gayi Selleck Staurosporine are probably subjected to higher mortality before competition for refuges intensifies. Here, through laboratory experiments, we quantified the strength of intra and inter-cohort cannibalism

and inter-specific predation as probable sources of differential post-settlement mortality. Intra-cohort cannibalism (among recruits of same size) accounted for the mortality of up to 30% of recruits in both species, with no evidence of density-dependent effects on mortality. Rates of cannibalism between juveniles and recruits (inter-cohorts) were also similar between the two species. Both species exhibit type III functional responses of juvenile predators with a tendency to consume heavily upon the most abundant recruits (A. gayi in the field), which could potentially provide A. hassleri recruits with a “virtual refuge” from the inter-cohort predation in the field. The combination of these different sources of mortality might contribute to the large reduction in abundance

of A. gayi recruits by the time they reach juvenile stages. Our results illustrate the complexity of mechanisms that can underlay patterns of distribution and relative abundances

ERK pathway inhibitors among competitors through different life stages, especially among coexisting species in which attacking peers can provide higher rewards later in development than just the energy obtained from other food. (C) 2013 Elsevier B.V. All rights reserved.”
“The synthesis and functionalization of carbon nanoparticles with PEG(200) and mercaptosuccinic acid, rendering fluorescent carbon dots, is described. Fluorescent carbon dots (maximum excitation and emission check details at 320 and 430 nm, respectively) with average dimension 267 nm were obtained. The lifetime decay of the functionalized carbon dots is complex and a three component decay time model originated a good fit with the following lifetimes: tau (1) = 2.71 ns; tau (2) = 7.36 ns; tau (3) = 0.38 ns. The fluorescence intensity of the carbon dots is affected by the solvent, pH (apparent pK (a) of 7.4 +/- 0.2) and iodide (Stern-Volmer constant of 78 +/- 2 M-1).”
“The purpose of this study was to isolate and purify lipopolysaccharide (LPS) from A. tumefaciens and E. coli and compare its ability to produce nitric oxide and TNF-a in peritoneal mice macrophages. We isolated and purified LPS from A. tumefaciens and E.coli. The endotoxin activity of LPS extracted from A. tumefaciens and E.