New least squares solutions for estimating the average centre of rotation and the axis of rotation.

A new method is proposed for estimating the parameters of ball joints, also known as spherical or revolute joints and hinge joints with a fixed axis of rotation. The method does not require manual adjustment of any optimisation parameters and produces closed form solutions. It is a least squares solution using the whole 3D motion data set. We do not assume strict rigidity but only that the markers maintain a constant distance from the centre or axis of rotation. This method is compared with other methods that use similar assumptions in the cases of random measurement errors, systematic skin movements and skin movements with random measurement noise. Simulation results indicate that the new method is superior in terms of the algorithm used, the closure of the solution, consistency and minimal manual parameter adjustment. The method can also be adapted to joints with translational movements.     

Quantification of Magnetically Induced Changes in ECM Local Apparent Stiffness

The stiffness of the extracellular matrix (ECM) is known to influence cell behavior. The ability to manipulate the stiffness of ECM has important implications in understanding how cells interact mechanically with their microenvironment. This article describes an approach to manipulating the stiffness ECM, whereby magnetic beads are embedded in the ECM through bioconjugation between the streptavidin-coated beads and the collagen fibers and then manipulated by an external magnetic field. It also reports both analytical results (obtained by formal modeling and numerical simulation) and statistically meaningful experimental results (obtained by atomic force microscopy) that demonstrate the effectiveness of this approach. These results clearly suggest the possibility of creating desired stiffness gradients in ECM in vitro to influence cell behavior.     

The fungicidal efficacy of various commercial disinfectants used in the food industry

The antifungal effects of eight commercial disinfectants namely alcohol, peracetic acid, iodophors, aldehydes, quaternary amine compounds (QAC, a, b and c), and a chlorine-based agent were assessed at different concentrations. The time taken for these disinfectants to kill different microorganisms was used to assess their efficacy. The microorganisms tested were six yeasts,Saccharomyces cerevisiae, Saccharomyces uvarum, Kloeckera apiculata, Candida oleophila, Metschnikowia fructicola, Schizosaccharomyces pombe, and two moulds,Aspergillus niger (5 strains) andPenicillium roqueforti (5 strains). The disinfectants QAC (a) and QAC (c) were the most effective against all the microorganisms tested. The chlorine-based disinfectant worked most efficiently against the moulds at all concentrations used (0.5, 1.0, 1.5 and 2.0%). Peracetic acid and alcohol based disinfectants were most effective against the yeasts than mould. Tested yeasts were more resistant to the aldehyde and iodophors base disinfectants than the others.     

Analysis of anger expression style--continuous anger and personality types of professional soccer players

The purpose of this study was to analyse the anger expression styles, the continuous anger and personality types of players who play football in the professional league. The research group consisted of 133 soccer players who are playing in sports teams in the Turkish Super League: Ankara Sport Club, Gen?lerbirli?i Sports Club and Hacettepe Sports Club in the first league, Turk Telekom sports in the second league, and Ke?i?ren Gücü Sports and Ankarademir Sports playing in the third league in the 2008-2009 football season. The Eysenck personality inventory was modified to Turkish by Bayar in 1983, having been developed by Eysenck and Eysenck in 1975 and the continuous anger-anger style scale (SOTO) was modified to Turkish by Ozer in 1994. The state trait anger scale (STAS) was originally developed by Spielberger in 1983. All these were used on soccer players participating in the study to determine the continuous anger and anger styles in this study. In the interpretation of data, a meaningfulness of p < 0.05, was applied by using regression analysis, the Kruskal Wallis Test, the one-way variance analysis (ANOVA) test and the Tukey test to find the differences among the groups. The SPSS (Statistical Package for Social Sciences) programme was used to find the accounted values and to evaluate the data. According to the results of this study, regarding the education level variable, while there was a meaningful difference between the continuous anger sub-dimension and anger control sub-dimension than continuous anger-anger expression styles, no significant difference was found among personality type sub-dimensions (psychoticism, extrovert, neurotic, false). In addition, a significant relationship was found between psychoticism, extrovert, neurotic, and lie sub-dimensions and the personality type sub-dimensions of professional players' constant anger-anger expression styles.     

ECOLOGICAL DIFFERENTIATION BETWEEN SYMPATRIC PSEUDOCRYPTIC SPECIES IN THE ESTUARINE BENTHIC DIATOM NAVICULA PHYLLEPTA (BACILLARIOPHYCEAE)1

The occurrence of cryptic and pseudocryptic species, often living in sympatry, is widespread among microalgae. This phenomenon raises important questions about niche partitioning between these closely related species. To date, however, few studies have addressed the ecological mechanisms underlying sympatry in cryptic and pseudocryptic species. As a result, we have only a limited understanding of the factors that govern their distribution along environmental gradients. Here, we used the ribosomal internal transcribed spacer (ITS), 18S rRNA gene, and the RUBISCO LSU (rbcL) chloroplast gene sequence data together with cell wall morphology to show that estuarine populations of the widespread and common benthic diatom Navicula phyllepta Kütz. consist of pseudocryptic species. Growth rate measurements in function of salinity showed that N. phyllepta strains assigned to the different species differed in their tolerance to low salinities (<5 practical salinity units, psu), which was reflected by their different (but widely overlapping) distribution in the Westerschelde estuary (the Netherlands). Multiple regression analyses of the factors determining the abundance of the different species in field samples revealed that, in addition to salinity, sediment type and ammonium concentrations were probably equally important. Our results show that N. phyllepta sensu lato comprises different species with specialized ecophysiological characteristics rather than generalists with a broad adaptability to different environmental conditions.