High performance and meeting participation: An observational study in software design teams.

This study compared high and moderate performers' involvement in cooperation processes. The author used an observational method to examine meeting participation of 60 software professionals from 10 software projects. Analyses showed that high performers participated more in the overall meeting process. In poorly structured meetings, high performers contributed more to process regulation activities, such as meeting management, goal setting, problem comprehension, and feedback seeking. No differences in process regulation activities were found for highly structured meetings. Contributions to team processes as a whole differed largely across individual team members, with high performers playing an important role and showing a high adaptation to the specific situational requirements. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intra-muscular and inter-muscular variation in carbon turnover of ovine muscles as recorded by stable isotope ratios

In the case of muscle-based foods, the incorporation of dietary isotopic signals into muscle tissue is a dynamic process and it is not known whether all muscles, or locations within a muscle, have the same isotopic composition. Therefore, an experiment was conducted in which 28 lambs were switched from a control diet to an isotopically distinct experimental diet offered at two different energy allowances (EA). Small, albeit significant, differences were detected in tissue carbon (C) turnover within the muscle Longissimus dorsi. Inter-muscular comparison showed similar C half-lives for four of the five analysed muscles. The results also clearly demonstrated that the EA had a significant impact on intra- and inter-muscular C turnover. The findings of similar tissue C turnover of several muscles sold as meats and the comparable tissue-diet fractionation of the analysed muscles (both within the same EA) will enable scientists to analyse different meat samples according to availability without introducing large biases. However, EA must be considered a factor of uncertainty.     

Hair mercury levels in relation to fish consumption in a community of the Moroccan Mediterranean coast

Coastal populations with high seafood consumption in the Mediterranean have a significant exposure to dietary methylmercury, and areas where environmental mercury pollution is an issue due to industrial activities are of special concern. The study was undertaken with the aim of assessing methylmercury exposure through fish consumption in a community of north Morocco and characterizing the relevant health risk. Concentrations of total mercury were determined in human hair, a biomarker of methylmercury exposure, and in locally consumed fish by cold vapour atomic absorption spectrophotometry. Based on consumption frequencies reported by the 108 subjects included in the study the weekly intake of methylmercury was estimated and biomarker data were evaluated in relation to the estimated intake and the sociodemographic characteristics of the population. Multiple regression analysis was employed for the interpretation of hair mercury data in relation to fish consumption frequency, gender and the age of individuals. Mercury concentrations in hair ranged from 0.22 to 9.56 µg g^-1 (geometric mean = 1.79 µg g^-1) and were closely related to fish intake. Fisherman and their families consumed fish three to five times per week and were the most exposed population subgroup. A high proportion of women of child-bearing age (50%) had relatively high levels of mercury in their hair (3.08-7.88 µg g^-1).     

Athletic classmates, physical self-concept, and free-time physical activity: A longitudinal study of frame of reference effects.

The systematic analysis of factors that promote or impede physical activity in children is an urgent task for educational researchers. The present study investigated the reciprocal relationship between physical self-concept, teacher-assigned grades in physical education classes, and free-time physical activity, and analyzed positive and negative consequences of being in a class with high class-average physical ability. Data from a large, representative sample of 1,095 preadolescents from 66 classrooms were examined within a longitudinal framework. Multilevel analyses showed that membership in a class with high class-average physical ability was associated with lower physical self-concept and free-time physical activity and highlighted the significant role of teacher-assigned grades in the development of physical self-concept and physical activity. Furthermore, as predicted, there were positive reciprocal effects between physical self-concept and physical activity levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of geometry and solids concentration on the hydrodynamics and mass transfer of a rectangular airlift reactor for marine sediment and soil bioremediation

Hydrodynamics and mass transfer characteristics of a three-phase airlift reactor were studied in a rectangular split-vessel reactor and using an air-seawater-marine sediment system. Experiments were conducted over a range of downcomer to riser cross-sectional area ratios (A_D/A_R = 0.65 to 1.0) for two-phase systems and for five sediment concentrations (5 to 25% w/v) using marine sediments. The influence of higher sediment concentrations (30 to 50% w/v) was examined for A_D/A_R = 1. The presence of fine sediment particles in the system had little effect on hydrodynamic and mass transfer parameters compared to the two-phase systems up to 25% loading, decreasing at higher loadings. The airlift reactor was found to meet the dissolved oxygen demand needed for a contaminated sediment treatment process. Axial distribution of the particles was uniform along the riser and the downcomer. Correlations were developed that described the hydrodynamic and mass transfer behaviour for all experimental conditions examined.     

Seed-mediated electrochemical growth of gold nanostructures on indium tin oxide thin films

Two-dimensional gold nanostructures (Au NSs) were fabricated on amine-terminated indium tin oxide (ITO) thin films using constant potential electrolysis. By controlling the deposition time and by choosing the appropriate ITO surface, Au NSs with different shapes were generated. When Au NSs were formed directly on aminosilane-modified ITO, the surface roughness of the interface was largely enhanced. Modification of such Au NSs with n-tetradecanethiol resulted in a highly hydrophobic interface with a water contact angle of 144°. Aminosilane-modified ITO films further modified with colloidal Au seeds before electrochemical Au NSs formation demonstrated interesting optical properties. Depending on the deposition time, surface colors ranging from pale pink to beatgold-like were observed. The optical properties and the chemical stability of the interfaces were characterized using UV-vis absorption spectroscopy. Well-defined localized surface plasmon resonance signals were recorded on Au-seeded interfaces with λ_max = 675 ± 2 nm (deposition time 180 s). The prepared interfaces exhibited long-term stability in various solvents and responded linearly to changes in the corresponding refractive indices.     

Solvent-free chemical functionalization of hydrogen-terminated boron-doped diamond electrodes with diazonium salts in ionic liquids

This paper reports on green chemical functionalization of hydrogen-terminated boron-doped diamond (BDD) surfaces with aryldiazonium salts in the presence of ionic liquids. The reaction takes place at room temperature in air without any external bias in either hydrophobic (1-butyl-3-methylimidazolium hexafluorophosphate) or hydrophilic (1-butyl-3-methylimidazolium methyl sulfate) ionic liquids. The resulting surfaces were characterized using X-ray photoelectron spectroscopy and electrochemical measurements.     

Microstructural analysis of residual projectiles—A new method to explain penetration mechanisms

In the present work it is shown that metallographic analysis can supply a lot of detailed information about metallurgical events which happen during the penetration of metallic projectiles into armor steel. With the help of these findings models of penetration processes are derived. The deformation, fracture, and phase transformation processes of projectiles are investigated, which consist of tungsten, a tool steel, and a tungsten heavy metal, respectively. These were shot into armor steel at velocities between 1000m/s and 2000 m/s. The extensively deformed tungsten and the brittle steel form two opposite poles; between those the heavy metal takes a mid position. The more ductile a material is, the sooner its penetration approaches the piercing of a liquid jet. On the other hand, in a brittle material quick rupture is followed by turbulent motion and friction welding of the fragments. In this case extensive deformation is observed only in the skin layer of a fragment and in shear bands. Special attention is drawn to features which are characteristic for ballistic piercing processes,e.g., molten films and adiabatic shear deformation. Formerly Research Scientist at the Hochschule der Bundeswehr in Hamburg, West Germany, and thereafter at an institute in France doing military research     

Novel TTLL5 Variants Associated with Cone-Rod Dystrophy and Early-Onset Severe Retinal Dystrophy

Variants of the TTLL5 gene, which encodes tubulin tyrosine ligase-like family member five, are a rare cause of cone dystrophy (COD) or cone-rod dystrophy (CORD). To date, only a few TTLL5 patients have been clinically and genetically described. In this study, we report five patients harbouring biallelic variants of TTLL5. Four adult patients presented either COD or CORD with onset in the late teenage years. The youngest patient had a phenotype of early onset severe retinal dystrophy (EOSRD). Genetic analysis was performed by targeted next generation sequencing of gene panels and assessment of copy number variants (CNV). We identified eight variants, of which six were novel, including two large multiexon deletions in patients with COD or CORD, while the EOSRD patient harboured the novel homozygous p.(Trp640*) variant and three distinct USH2A variants, which might explain the observed rod involvement. Our study highlights the role of TTLL5 in COD/CORD and the importance of large deletions. These findings suggest that COD or CORD patients lacking variants in known genes may harbour CNVs to be discovered in TTLL5, previously undetected by classical sequencing methods. In addition, variable phenotypes in TTLL5-associated patients might be due to the presence of additional gene defects.