Synthesis and activation of Pt nanoparticles with controlled size for fuel cell electrocatalysts

Well-dispersed Pt nanoparticles with controlled size and narrow size distribution were prepared by polyalcohol reduction of platinum acetylacetonate, using oleylamine as a capping agent. The particle size was varied from 3.5 nm to 11.5 nm by decreasing the amount of oleylamine added in the synthesis. Size selection of the as-prepared particles by solvent fractionation yielded nearly monodispersed Pt particles. The as-prepared particles were loaded on a carbon support by physical deposition, but showed no electrocatalytic activity due to the oleylamine bound to the particle surface. The particles were activated for electrocatalysis after heating the particles in air at 185 °C for 5 h, conditions that gave no particle-sintering and no oxidation. Cyclic voltammetry showed that the particles after the heat treatment in air were electrocatalytically active for methanol oxidation. The smaller 3.5 nm and 4.0 nm Pt particles had a higher intrinsic activity for methanol oxidation, but a lower tolerance to CO poisoning, compared with 6.0 nm, 9.5 nm and 11.5 nm particles. CO-stripping results suggest that CO is more easily oxidized on larger Pt particles.     

Tabletability of Maltodextrins and Acetaminophen Mixtures

Tabletability of five types of maltodextrin, a filler/binder excipient, was studied by testing their loading potentials with acetaminophen. The formulations consisted of excipient and acetaminophen at five different ratios and magnesium stearate at a 0.5% concentration. These mixtures were compacted employing an Integrated Compaction Research System at a constant punch velocity of 100 mm/sec. under varying applied pressures from 50 to 450 MPa. Compaction data were evaluated using the total work of compaction vs applied pressure plots whilst the post-compaction tests included the measurements of crushing force, disintegration time, and friability of the resulting tablets. Both the energy involved during the compaction of a formulation and the crushing force values of the resulting tablets decreased as the amount of the maltodextrin in a formulation was reduced. Maltodextrins exhibited adequate binding potential at acetaminophen drug loading levels of only up to twenty-five percent. The disintegration times of the tablets containing maltodextrins were generally prolonged and this was found to be due to the formation of a “gel” layer around the tablet which formed on immersion into water. The tabletability of maltodextrins were also compared to that of Fast-Flo lactose, and the compactability of these excipients were found to be similar.     

Tower of London performance in relation to Magnetic Resonance Imaging following closed head injury in children.

To investigate the relationship of severity of pediatric closed head injury (CHI), the contribution of frontal lobe lesions, and age at testing (6–10 yr olds vs 11–15 yr olds) to cognitive deficit, 134 head-injured patients were given the Tower of London (TOL) task and underwent magnetic resonance imaging. 89 normal controls were given the TOL for comparison. Severity of CHI and age at testing were strongly related to cognitive performance on the TOL, including the frequency of breaking the rules. Volume of frontal lobe lesion (but not extrafrontal lesion) contributed to the prediction of perfomance on the TOL even after severity of injury was taken into account. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Preventing weight gain in adults: A pound of prevention.

Evaluated the feasibility and effectiveness of a program for weight gain prevention (WGP) in normal adults. 219 Ss were randomized to either WGP treatment or no treatment for 12 mo. The treatment group received monthly newsletters relating to weight management, participated in a financial incentive system, and were offered an optional 4-session education course in the 6th mo of the program. Results demonstrate high interest in WGP among Ss who were not objectively overweight. Participation, as measured by return of postcards sent with each newsletter, was approximately 75%. Results after 1 yr show a net weight loss of 1.8 lb in the group receiving the program compared with controls. 82% of participants maintained or lost weight, compared with 56% of controls. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Parallel branch-and-bound search in Parlog

The concurrent logic languages, of which Parlog is one, have been promoted as a new generation of software languages specifically designed for parallel programming. This paper investigates their application to a search problem commonly used as an illustration of artificial intelligence techniques, the 8-puzzle. It notes that programs written in the concurrent logic languages which do not pay attention to the parallelism can fall into two possible traps: either there is little real parallelism in them due to data dependencies, or there is too much parallelism and any practical architecture will be overwhelmed. A solution which controls the parallelism using user-defined priorities is proposed. This solution has the advantage of being architecture-independent.     

A strategy for integrating product conceptualization and bid preparation

Collaboration with other members of the supply chain is one means by which small and medium sized enterprises (SMEs) can compete in today’s global business environment. Thus, early stages of the new product development process involve both technical activities, e.g., product platform definition, and commercial activities, e.g., bidding for contracts. This paper introduces an integrated collaborative bidding and design system (CBDS) to help SMEs coordinate the two aspects. General sorting was employed for initial requirements acquisition and platform definition; while a self-organizing map (SOM) neural network was combined with a concurrent cost-schedule estimation strategy for refinement of design options and bid evaluation/preparation. A case study on cellular phone design was then applied for illustrating the proposed prototype system.     

Isolation and DNA sequence of the STE14 gene encoding farnesyl cysteine: Carboxyl methyltransferase

We isolated a mutant defective in C-terminal farnesyl cysteine:carboxyl methyltransferase activity from a screen for mutations causing a -specific sterility. A genomic fragment was cloned from a yeast multi-copy library that restored mating. Both the cloned gene and the sterile mutation were allelic to the STE14 gene. A ste14-complementing 2·17 kb BamHI fragment subclone was sequenced and found to encode a 239 amino acid protein with a molecular weight of 27,887 Daltons. The hydrophobicity profile of the methyltransferase reveals the presence of at least five potential transmembrane domains. In comparisons of the C-terminal methyltransferase amino acid sequence with those in the PIR and Swiss protein databases, no significantly similar sequences were found nor were conserved regions from other methyltransferases present.     

Publication and citation of alcohol and drug articles in journals of the American Psychological Association.

Examined publishing practices of the American Psychological Association (APA) in the alcohol and drug area. Although the total number of articles published by APA increased only 7.6% between 1984 and 1990, the number of alcohol and drug articles more than doubled. Despite the disproportionate growth of alcohol and drug articles between 1984 and 1990, only 3.8% of 1,408 APA articles published in 1990 addressed alcohol and drug use issues. An earlier investigation by M. O. Howard and D. A. Howard (1992) reported that 541 articles published in 1984 in 12 alcohol and drug specialty journals received an average of 3.48 citations by the end of 1988. Alcohol and drug articles published by APA in 1984 received more than 4 times as many citations during this period. Also, alcohol and drug articles published by APA received significantly more citations between 1984 and 1988 than those published in specialty journals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)