This hypothesis is corroborated by microscopic observations in diluted systems. These experiments show that the aspect ratio (length/diameter) of the field-induced structures increases with the gap thickness. Theoretical analysis shows that the increase in the storage modulus with gap thickness can be explained by a decrease in the demagnetizing factor of these structures and, as

a consequence, by an increase in the restoring torque, acting on them. The dissipation effects in the suspension under oscillating flow are rather produced by contact friction between the particles in the dense structures. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3498804]“
“There have been few studies on Magellanic penguins (Spheniscus magellanicus). In 2008, these penguins washed ashore along the Brazilian AG-881 concentration coast in unusually high numbers, some reaching as far as northeast Brazil. As Magellanic penguins show little sexual Sapanisertib dimorphism, sex determination by morphological features is not accurate. Here, we tested a molecular procedure for sexing specimens of S. magellanicus washed ashore along the coasts of Sergipe, Rio de Janeiro and Rio Grande do Sul in 2008, comparing the sex ratio between these

localities. Tissue samples were collected from 135 dead, beached specimens. We carried out total genomic DNA extraction and CHD-Z/CHD-W gene amplification by PCR using P2 and P8 primers. AZD4547 manufacturer Amplicons were separated by 12% acrylamide gel electrophoresis. We found a greater proportion of females (70%). Sex could be determined because females have two intronic regions of CHD gene of different size in the sex chromosomes, visualized as two bands on the gel (380 and 400 bp approximately), while males have only one (400 bp). Therefore, this method proved to be effective and sensitive for sex determination of S. magellanicus individuals. Data on sex ratios

are useful for understanding the dynamics and ecology of Magellanic penguin populations.”
“Predicting protein structure from primary sequence is one of the ultimate challenges in computational biology. Given the large amount of available sequence data, the analysis of co-evolution, i.e., statistical dependency, between columns in multiple alignments of protein domain sequences remains one of the most promising avenues for predicting residues that are contacting in the structure. A key impediment to this approach is that strong statistical dependencies are also observed for many residue pairs that are distal in the structure. Using a comprehensive analysis of protein domains with available three-dimensional structures we show that co-evolving contacts very commonly form chains that percolate through the protein structure, inducing indirect statistical dependencies between many distal pairs of residues.