Local versus global optimal sports techniques in a group of athletes

Various optimization algorithms have been used to achieve optimal control of sports movements. Nevertheless, no local or global optimization algorithm could be the most effective for solving all optimal control problems. This study aims at comparing local and global optimal solutions in a multistart gradient-based optimization by considering actual repetitive performances of a group of athletes performing a transition move on the uneven bars. Twenty-four trials by eight national-level female gymnasts were recorded using a motion capture system, and then multistart sequential quadratic programming optimizations were performed to obtain global optimal, local optimal and suboptimal solutions. The multistart approach combined with a gradient-based algorithm did not often find the local solution to be the best and proposed several other solutions including global optimal and suboptimal techniques. The qualitative change between actual and optimal techniques provided three directions for training: to increase hip flexion–abduction, to transfer leg and arm angular momentum to the trunk and to straighten hand path to the bar.     

Four GH11 xylanases from the xylanolytic fungus Talaromyces versatilis act differently on (arabino)xylans

The filamentous fungus Talaromyces versatilis produces a wide range of cellulolytic and hemicellulolytic enzymes such as xylanases. The recent accessibility to the T. versatilis genome allows identifying two new genes, xynE and xynF, encoding glycoside-hydrolases from family GH11. Both genes were cloned and expressed in the methylotrophic yeast Pichia pastoris in order to compare these new xylanases with two other GH11 xylanases from T. versatilis (XynB and XynC) that were previously reported. High-level expression of recombinant enzymes was obtained for the four enzymes that were purified to homogeneity. The XynB, XynC, XynE and XynF enzymes have molecular masses of 34, 22, 45 and 23 kDa, an optimal pH between 3.5 and 4.5 and an optimal temperature between 50 °C and 60 °C. Interestingly, XynF has shown the best thermal stability at 50 °C for at least 180 min with a weak loss of activity. The four xylanases catalysed hydrolysis of low viscosity arabinoxylan (LVAX) with K _m(app) between 11.5 and 23.0 mg.mL^?1 and k _cat/K _m(app) 170 and 3,963 s^?1 mg^?1.mL. Further investigations on the rate and pattern of hydrolysis of the four enzymes on LVAX showed the predominant production of xylose, xylobiose and some (arabino)xylo-oligosaccharides as end products. The initial rate data from the hydrolysis of short xylo-oligosaccharides indicated that the catalytic efficiency increased with increasing degree of polymerisation of oligomer up to 6, suggesting that the specificity region of XynE and XynF spans at least six xylose residues. Because of their attractive properties, T. versatilis xylanases might be considered for biotechnological applications.     

Evolution of reproductive isolation within a parasitic fungal species complex

Despite important advances in the last few years, the evolution of reproductive isolation (RI) remains an unresolved and critical gap in our understanding of speciation processes. In this study, we investigated the evolution of RI among species of the parasitic fungal species complex Microbotryum violaceum, which is responsible for anther smut disease of the Caryophyllaceae. We found no evidence for significant positive assortative mating by M. violaceum even over substantial degrees of genetic divergence, suggesting a lack of prezygotic isolation. In contrast, postzygotic isolation increased with the genetic distance between mating partners when measured as hyphal growth. Total RI, measured as the ability of the pathogen to infect and produce a diploid progeny in the host plant, was significantly and positively correlated with genetic distance, remaining below complete isolation for most of the species pairs. The results of this study, the first one on the time course of speciation in a fungus, are therefore consistent with previous works showing that RI generally evolves gradually with genetic distance, and thus presumably with time. Interestingly, prezygotic RI due to gamete recognition did not increase with genetic distance, in contrast to the pattern found in plants and animals.     

Evolutionary response to coexistence with close relatives: increased resistance against specialist herbivores without cost for climatic‐stress resistance

Why can hosts coexist with conspecifics or phylogenetically proximate neighbours despite sharing specialist enemies? Do the hosts evolve increased enemy resistance? If so, does this have costs in terms of climatic‐stress resistance, or in such neighbourhoods, does climatic‐stress select for resistances that are multifunctional against climate and enemies? We studied oak (Quercus petraea) descendants from provenances of contrasting phylogenetic neighbourhoods and climates in a 25‐year‐old common garden. We found that descendants from conspecific or phylogenetically proximate neighbourhoods had the toughest leaves and fewest leaf miners, but no reduction in climatic‐stress resistance. Descendants from such neighbourhoods under cold or dry climates had the highest flavonol and anthocyanin levels and the thickest leaves. Overall, populations facing phylogenetically proximate neighbours can rapidly evolve herbivore resistance, without cost to climatic‐stress resistance, but possibly facilitating resistance against cold and drought via multifunctional traits. Microevolution might hence facilitate ecological coexistence of close relatives and thereby macroevolutionary conservatism of niches.     

Amphipol-Mediated Screening of Molecular Orthoses Specific for Membrane Protein Targets

Specific, tight-binding protein partners are valuable helpers to facilitate membrane protein (MP) crystallization, because they can i) stabilize the protein, ii) reduce its conformational heterogeneity, and iii) increase the polar surface from which well-ordered crystals can grow. The design and production of a new family of synthetic scaffolds (dubbed αReps, for “artificial alpha repeat protein”) have been recently described. The stabilization and immobilization of MPs in a functional state are an absolute prerequisite for the screening of binders that recognize specifically their native conformation. We present here a general procedure for the selection of αReps specific of any MP. It relies on the use of biotinylated amphipols, which act as a universal “Velcro” to stabilize, and immobilize MP targets onto streptavidin-coated solid supports, thus doing away with the need to tag the protein itself.     

Armadillo 1.1: an original workflow platform for designing and conducting phylogenetic analysis and simulations

In this paper we introduce Armadillo v1.1, a novel workflow platform dedicated to designing and conducting phylogenetic studies, including comprehensive simulations. A number of important phylogenetic and general bioinformatics tools have been included in the first software release. As Armadillo is an open-source project, it allows scientists to develop their own modules as well as to integrate existing computer applications. Using our workflow platform, different complex phylogenetic tasks can be modeled and presented in a single workflow without any prior knowledge of programming techniques. The first version of Armadillo was successfully used by professors of bioinformatics at Université du Quebec à Montreal during graduate computational biology courses taught in 2010-11. The program and its source code are freely available at: .