Psychosocial effects of unrelated bone marrow donation: experiences of the National Marrow Donor Program

In this study, we investigated the psychosocial effects of unrelated marrow donation. Survey questionnaires were administered pre-donation, shortly post-donation, and 1 year post-donation to all donors through the National Marrow Donor Program over a 3-year period. Univariate, bivariate, and multivariate analyses were then performed. Donors were generally quite positive about the donation 1 year post-donation: 87% felt it was "very worthwhile" and 91% would be willing to donate again in the future. Marrow donors were more likely than kidney donors to feel better about themselves as a result of the donation (P < .001). Donors with longer collection times, in general, had less positive psychosocial outcomes from the donation. Donors who experienced lower back pain or difficulty walking as a result of the donation were more likely to experience the donation as more stressful and painful than expected, but no more likely to experience it as less positive emotionally than donors who did not experience these side effects.     

Two-step homogeneous conjugation and hydrogenation of methyl esters of unsaturated fatty acids

A new approach to the selective hydrogenation of unsaturated fatty acids is suggested. It consists of a two step process. The first is a selective conjugation of the double bonds, while the second consists of the hydrogenation reaction using a catalyst which is specific to conjugated systems. Potassiumt-butoxide was used as a conjugation catalyst and its activity and selectivity were tested at various concentrations, different molar ratios of catalyst to oil, and in various solvents. Phenanthrene chromium tricarbonyl was used as the hydrogenation catalyst and its activity tested at various concentrations, temperatures and in various solvents. UN Expert, Physical Organic Chemist.     

Comparison of plasmid and genomic DNA calibrants for the quantification of genetically modified ingredients

Real-time PCR is the method of choice for the quantification of the genetically modified (GM) content of food. Recent EU Commission recommendations advocate expressing the GM content as the percentage of the number of GM target DNA sequences per target taxon specific sequence. The provision of reference materials certified for their copy number content, for example in the form of plasmids, are hence desirable to fulfil this EU recommendation. An inter-laboratory trial was conducted to compare plasmid DNA to the more traditional genomic DNA approach for quantitative PCR calibration in terms of copy numbers, using the model system of Roundup Ready? soya. Data was analysed from 48 randomised real-time quantitative PCR plates under conditions of reproducibility across three international laboratories. Results demonstrated that the specific plasmid DNA used in the laboratory trial provided a suitable alternative to genomic DNA for use as a calibrant in GM quantification. In the current investigation, plasmid calibrants gave equal or better performance characteristics in terms of precision and closeness to the expected value, than their genomic equivalents.     

Genetic code origins: tRNAs older than their synthetases?

We present a phylogenetic analysis to determine whether a given tRNA molecule was established in evolution before its cognate aminoacyl-tRNA synthetase. The earlier appearance of tRNA versus their metabolically related enzymes is a prediction of the RNA world theory, but the available synthetase and tRNA sequences previously had not allowed a formal comparison of their relative time of appearance. Using data recently obtained from the emerging genome projects, our analysis points to the extant forms of lysyl-tRNA synthetase being preceded in evolution by the establishment of the identity of lysine tRNA.     

How temporal distance changes novices' attitudes towards unconventional arts.

The authors suggest that, just like other attitudes, attitudes toward art may be malleable, and may thus also depend on situational factors. In particular, the authors propose that thinking styles vary within the situation and that an abstract versus concrete thinking style has an influence on attitudes toward conventional (e.g., Mona Lisa by da Vinci) versus unconventional (e.g., Fat Corner by Beuys) artworks. Construal Level Theory predicts that when people think about the distant future they automatically start thinking in a more abstract way, relative to when people think about the near future, which is supposed to elicit a concrete thinking style. In an experiment, the authors asked participants to think about their lives a year from now or tomorrow. Afterward, in an allegedly unrelated task, participants were asked to evaluate conventional and unconventional artworks. Results showed that participants that had thought about distant events and presumably thought more abstractly were more likely to include unconventional artworks into the category of arts than participants that had thought about near events, and thus presumably thought in more concrete terms. Implications for applied settings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Human cytoplasmic isoleucyl-tRNA synthetase: selective divergence of the anticodon-binding domain and acquisition of a new structural unit

We show here that the class I human cytoplasmic isoleucyl-tRNA synthetase is an exceptionally large polypeptide (1266 aa) which, unlike its homologues in lower eukaryotes and prokaryotes, has a third domain of two repeats of an approximately 90-aa sequence appended to its C-terminal end. While extracts of Escherichia coli do not aminoacrylate mammalian tRNA with isoleucine, expression of the cloned human gene in E. coli results in charging of the mammalian tRNA substrate. The appended third domain is dispensable for detection of this aminoacylation activity and may be needed for assembly of a multisynthetase complex in mammalian cells. Alignment of the sequences of the remaining two domains shared by isoleucyl-tRNA synthetases from E. coli to human reveals a much greater selective pressure on the domain needed for tRNA acceptor helix interactions and catalysis than on the domain needed for interactions with the anticodon. This result may have implications for the historical development of an operational RNA code for amino acids.     

Structure, anisotropy and fractals in compressed cohesive powders

Correlation functions are commonly used to characterise the microstructure of materials. The correlation function is then related to other properties or phenomenology connected to the investigated material. In this paper, we investigate the bulk microstructure in two cohesive powders — a silica powder containing spherical grains and a carbon nanotube powder, by means of Spin-echo Small-angle Neutron Scattering technique. We show that, for the silica powder, the typical size of the heterogeneities decreases with increasing strain, thus linking microscopic deformations with the macroscopic ones. Measurements also show that the compressed silica powder is isotropic in terms of its density distribution. On the compressed nanotube powder we are able to conclude that the applied uniaxial stress induces anisotropy in the density distribution. We are able to link the compressive strain with the measured anisotropy, thus creating the link between macroscopic and microscopic behaviours. Both powders are shown to have a fractal structure, and are characterised in terms of a fractal dimension.