Correlation of Structure and Photoelastic Response in Tin Phosphate Glass

Recently an empirical model was established to predict the photoelastic response of a glass based on its composition and the crystalline structure of its constituents. In the present work the model was tested in detail by comparing the local structure assessed by a combination of nuclear magnetic resonance and Mössbauer spectroscopy with the model predictions and the measured photoelastic response. The system investigated was (SnO)_x(P₂O₅)_1−x. It was found that while the original simple model based on data on the pure components predicted the composition of the zero stress-optic glass to within about 15 mol%, inclusion of data on mixed systems, more reflective of the true glass structure, gave substantial improvement of the prediction. This finding further confirms the relation of local bonding structure to the photoelastic response of glass.     

Unequal representation of women and men in energy company boards and management groups: Are there implications for mitigation?

This survey shows that female representation in boards and management groups of large energy companies in Germany, Spain and Sweden is far from being gender-equal. Of the 464 companies surveyed, 295 (64%) had no women at all in boards or management groups and only 5% could be considered gender-equal by having 40% or more women in such positions. Interviews with energy companies confirmed current trends that gender equality efforts within decision-making in business are weak or non-existent. The findings are discussed against the background of differences in risk perceptions among women and men, evidence of women’s impact on boards and companies’ performance and the substantial risks related to unabated climate change. Research is suggested for exploring potential impacts on energy companies' performance with more women in the boards when it comes to mitigation activities.     

The Conversion of UDP-Glc to UDP-Man: In Silico and Biochemical Exploration To Improve the Catalytic Efficiency of CDP-Tyvelose C2-Epimerases

A promiscuous CDP-tyvelose 2-epimerase (TyvE) from Thermodesulfatator atlanticus (TaTyvE) belonging to the nucleotide sugar active short-chain dehydrogenase/reductase superfamily (NS-SDRs) was recently discovered. TaTyvE performs the slow conversion of NDP-glucose (NDP-Glc) to NDP-mannose (NDP-Man). Here, we present the sequence fingerprints that are indicative of the conversion of UDP-Glc to UDP-Man in TyvE-like enzymes based on the heptagonal box motifs. Our data-mining approach led to the identification of 11 additional TyvE-like enzymes for the conversion of UDP-Glc to UDP-Man. We characterized the top two wild-type candidates, which show a 15- and 20-fold improved catalytic efficiency, respectively, on UDP-Glc compared to TaTyvE. In addition, we present a quadruple variant of one of the identified enzymes with a 70-fold improved catalytic efficiency on UDP-Glc compared to TaTyvE. These findings could help the design of new nucleotide production pathways starting from a cheap sugar substrate like glucose or sucrose.     

Phytochemical composition and in vitro antimicrobial and antioxidant activities of essential oils of three endemic Soqotraen Boswellia species

The chemical composition of three essential oils obtained from the barks of three endemic Boswellia species namely, Boswellia dioscorides, Boswellia elongata and Boswellia socotrana which were collected from the Soqotra Island (Yemen), was investigated. In parallel to that evaluation of their antimicrobial and antioxidant activities was also carried out. The investigation led to the identification of 72, 70 and 67 constituents for B.dioscorides, B. elongata, and B. socotrana, respectively. The B. dioscorides oil was found to have a high content of monoterpene hydrocarbons (32.8%) with α-thujene (9.3%) and α-pinene (8.3%) as main components. Whereas, the essential oil of B. elongata was characterised by high diterpene content (31.7%), in which incensol (14.8%) was found to be the major constituent. On the other hand, the oil obtained from the B. socotrana was found to be predominated of monoterpene hydrocarbons (26.4%) and oxygenated monoterpenes (30.7%) with p-cymene (13.0%), 2-hydroxy-5-methoxy-acetophenone (16.3%) and camphor (11.6%). All essential oils possessed antimicrobial activity especially against Gram-positive bacteria with MIC-values between 1.8 and 17.2 mg/ml. Furthermore, the DPPH-radical scavenging assay exhibited only weak antioxidant activities (28%) at 1.0 mg/ml.     

Improved signal-to-noise ratio in EPI sequences with highly asymmetric spin echo and highly asymmetric STEAM preparations (HASE-EPI and HASTEAM-EPI)

Magnetic Resonance Materials in Physics, Biology and Medicine - Alternative versions of echo-planar imaging (EPI) sequences with standard spin echo (SE) or stimulated echo acquisition mode (STEAM)...     

Fiber scaffolds of polysialic acid via electrospinning for peripheral nerve regeneration

Fiber scaffolds of bioactive polysialic acid have been prepared via electrospinning for peripheral nerve regeneration. The diameter, morphology and alignment of fibers in scaffolds were adjusted by variation of electrospinning parameters, which are decisive for the cell-scaffold interaction. Due to the high water solubility of polysialic acid (poly-α-2,8-N-acetylneuraminic acid) a photoactive derivative (poly-α-2,8-N-pentenoylneuraminic acid) was used to obtain stable fiber scaffolds in water by photochemical crosslinking. At the optimized fiber scaffolds good cell viability and directed cell proliferation along the fibers was achieved by cell tests with immortalized Schwann cells.     

CSCL for intellectually disabled pupils: Stimulating interaction by using a floor control mechanism

Computer-supported collaborative learning has an unexploited potential of becoming an effective learning method for pupils with intellectual disabilities. This paper aims at showing how some specific requirements of this target group may be met by structuring a learning situation with the help of floor control, which restricts the opportunities of a learning dyad to act simultaneously within the learning environment. It was expected that floor control could improve communication between pupils with intellectual disabilities by explicitly structuring and restricting activities in the learning environment and making it necessary for the pupils to communicate. To examine if floor control really supports the collaboration process in the hypothesized way, two different versions of a CSCL environment were implemented and compared. The results revealed improved task-related communication and a higher quality of interaction outcomes.     

The letter of recommendation effect in informant ratings of personality.

In most studies using informant reports of personality, the informants are recruited by the targets. Such informants may tend to like the targets and thus portray them in specific ways (e.g., too positively). Study 1 (N = 403) demonstrated the necessity to distinguish between “liking” and “knowing” in studying the relationships between informants and targets. Informants who liked their targets better described them more positively (i.e., as being more extraverted, agreeable, open, conscientious, and less neurotic). The association between personality ratings and liking was moderated by item evaluativeness. Liked targets were also described as being more similar to each other (range restriction), which would lower correlations of informant ratings of personality with external variables. Study 2 (N = 90) used a within-subjects design to disentangle actual personality differences between targets (substance) from the informants’ specific views on the targets (style). Ninety informants were asked to nominate targets they did not like. These targets then nominated informants of their own choice. Target-nominated informants liked the targets very much and described the targets’ personalities very positively and in ways that were highly redundant with the average target’s self-rating. There was evidence that lower liking may be associated with better accuracy. Higher subjective levels of knowing were not associated with better interrater agreement but with a greater willingness to describe targets negatively. Implications for the field of recruiting are discussed. Where possible, the choice of informants and referees should be made independent of the targets’ preferences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)