Changes in the sensitivity to appetitive and aversive arousal across adulthood.

In 2 cross-sectional studies, the authors examined age-related differences in the evaluation of emotional stimuli in 2 community samples, with participants ranging in age from young to older adulthood (18–81 years old). Pictures of the International Affective Picture System were used in Study 1, and written verbs were used in Study 2. Participants rated these stimuli along the 2 major affective dimensions of hedonic valence and emotional arousal, thus yielding a 2-dimensional affective space for each participant. Young adults showed the expected pattern of 2 distinct clusters of stimuli in this space, representing increasing pleasantness (appetitive activation) and unpleasantness (aversive activation) with increasing emotional arousal. In contrast, for older adults, emotional valence and arousal ratings were linearly related: Low-arousing stimuli were rated as most pleasant, and high-arousing stimuli were rated as most unpleasant. When regressed on age, these changes revealed a gradual decrease of appetitive activation (i.e., the relationship between pleasure and arousal) across adulthood and a linear increase in aversive activation (i.e., the relationship between displeasure and arousal). These results extend previous work on emotional development, adding information as to the role of emotional intensity for affective experience in different age groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Complexities in modeling of heterogeneous catalytic reactions

Catalysts are omnipresent in the chemical industry. Understanding of catalytic chemical reactions is crucial for a rational development of catalysts. The present paper describes approaches for simulating phenomena in heterogeneous catalysis on a molecular level. Modeling of porous structures and their fractal surfaces will be presented. Simulation of adsorption and diffusion of reactants and products inside the pores by means of various Monte Carlo and Molecular Dynamics algorithms is described, followed by quantum chemical methods for calculating reactions on the active centers. Optimization of pore structures and multiscaling procedures complete the picture.     

Preparation and characterization of novel nanometer-scale platinum electrodes

Observation of the oxidation–reduction processes occurring at the nanoelectrode–solution interface demonstrates how electrochemical behavior depends upon nanoelectrode size. The use of a modified form of pulsed laser ablation as an improved method to synthesize nanometer-scaled electrode materials easily and consistently is reported. This method of fabrication enables platinum metal nanoparticles averaging 3 nm in diameter and approximately 5.0 × 10¹¹ particles/cm² to be deposited onto silicon substrates using optimum ablation parameters. A platinum silicide phase exists at the interface of the platinum and silicon as a result of the ablation process. Electrochemical results demonstrate the presence of a large number of isolated platinum particles (1.1 × 10⁷ particles/cm²), separated by an average edge to edge distance of 14 nm, which are electrochemically active nanoelectrodes.     

RRD1, a component of the TORC1 signalling pathway,affects anaesthetic response in Saccharomyces cerevisiae

The molecular mechanisms of action of volatile anaesthetics remain unknown despite clinical use for over 150 years. While many effects of these agents have been characterized, clear insight into how these effects relate to the physiological state of anaesthesia has not been established. Volatile anaesthetics arrest cell division in Saccharomyces cerevisiae in a manner that parallels the anaesthetic actions of these drugs in mammals. To gain additional insight into the cellular activities of these drugs, we isolated genes that, when present on multi‐copy plasmids, render S. cerevisiae resistant to the volatile anaesthetic isoflurane. One of these genes, RRD1, encodes a subunit of the Tap42p–Sit4p–Rrd1p phosphatase complex that functions in the target of rapamycin complex 1 (TORC1) signalling pathway. In addition, we show that mutations in two other genes encoding components of the TORC1 pathway, GLN3 and URE2, also affect yeast anaesthetic response. These findings suggest that TORC1‐mediated signalling is involved in cellular response to volatile anaesthetics in S. cerevisiae. Copyright © 2009 John Wiley & Sons, Ltd.     

Hybrid polymer/silica vertical coupler switch with <-32 dBpolarisation-independent crosstalk

A modified hybrid polymer/silica 1×2 vertical coupler switch (VCS) with a polymer gap layer and a refractive index contrast of 0.008 has been designed, fabricated and characterised. The VCS exhibits low loss, low crosstalk, low switching power, and polarisation insensitivity. Using the 1×2 VCS as a building block, a 1×8 VCS matrix has been implemented     

The challenge of accurate software project status reporting: a two-stage model incorporating status errors and reporting bias

Software project managers perceive and report project status. Recognizing that their status perceptions might be wrong and that they may not faithfully report what they believe, leads to a natural question-how different is true software project status from reported status? Here, the authors construct a two-stage model which accounts for project manager errors in perception and bias that might be applied before reporting status to executives. They call the combined effect of errors in perception and bias, project status distortion . The probabilistic model has roots in information theory and uses discrete project status from traffic light reporting. The true statuses of projects of varying risk were elicited from a panel of five experts and formed the model input. The same experts estimated the frequency with which project managers make status errors, while the authors created different bias scenarios in order to investigate the impact of different bias levels. The true status estimates, error estimates, and bias levels allow calculation of perceived and reported status. The results indicate that at the early stage of the development process most software projects are already in trouble, that project managers are overly optimistic in their perceptions, and that executives receive status reports very different from reality, depending on the risk level of the project and the amount of bias applied by the project manager. Key findings suggest that executives should be skeptical of favorable status reports and that for higher risk projects executives should concentrate on decreasing bias if they are to improve the accuracy of project reporting.