False recognition of abstract versus common objects in older and younger adults: Testing the semantic categorization account.

Older adults often demonstrate higher levels of false recognition than do younger adults. However, in experiments using novel shapes without preexisting semantic representations, this age-related elevation in false recognition was found to be greatly attenuated. Two experiments tested a semantic categorization account of these findings, examining whether older adults show especially heightened false recognition if the stimuli have preexisting semantic representations, such that semantic category information attenuates or truncates the encoding or retrieval of item-specific perceptual information. In Experiment 1, ambiguous shapes were presented with or without disambiguating semantic labels. Older adults showed higher false recognition when labels were present but not when labels were never presented. In Experiment 2, older adults showed higher false recognition for concrete but not abstract objects. The semantic categorization account was supported. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of prosocial, individualistic, and competitive orientations: Theory and preliminary evidence.

The authors adopt an interdependence analysis of social value orientation, proposing that prosocial, individualistic, and competitive orientations are (a) partially rooted in different patterns of social interaction as experienced during the periods spanning early childhood to young adulthood and (b) further shaped by different patterns of social interaction as experienced during early adulthood, middle adulthood, and old age. Congruent with this analysis, results revealed that relative to individualists and competitors, prosocial individuals exhibited greater levels of secure attachment (Studies 1 and 2) and reported having more siblings, especially sisters (Study 3). Finally, the prevalence of prosocials increased—and the prevalence of individualists and competitors decreased—from early adulthood to middle adulthood and old age (Study 4). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Machining Planning for Tolerance Synthesis

The present paper deals with the preliminary study and the prototypical implementation of an expert system to quickly define an high level manufacturing sequence able to produce the assigned part tolerances. To do so, the expert system simulates the human reasoning process by applying specific knowledge and inferences. An assembly that is widely used to test the performances of different design methods represents the case study. This module belongs to a flexible and integrated environment that aims to automatically define both the tolerance specifications and the related process plan. Its aim is to support the designer during the definition of a functional project.     

Exploring the Biocatalytic Scope of Alditol Oxidase from Streptomyces coelicolor

The substrate scope of the flavoprotein alditol oxidase (AldO) from Streptomyces coelicolor A3(2), recombinantly produced in Escherichia coli, was explored. While it has been established that AldO efficiently oxidizes alditols to D ‐aldoses, this study revealed that the enzyme is also active with a broad range of aliphatic and aromatic alcohols. Alcohols containing hydroxy groups at the C‐1 and C‐2 positions like 1,2,4‐butanetriol (K_m=170 mM, k_cat=4.4 s⁻¹), 1,2‐pentanediol (K_m=52 mM, k_cat=0.85 s⁻¹) and 1,2‐hexanediol (K_m=97 mM, k_cat=2.0 s⁻¹) were readily accepted by AldO. Furthermore, the enzyme was highly enantioselective for the oxidation of 1,2‐diols [e.g., for 1‐phenyl‐1,2‐ethanediol the (R)‐enantiomer was preferred with an E‐value of 74]. For several diols the oxidation products were determined by GC‐MS and NMR. Interestingly, for all tested 1,2‐diols the products were found to be the α‐hydroxy acids instead of the expected α‐hydroxy aldehydes. Incubation of (R)‐1‐phenyl‐1,2‐ethanediol with ¹⁸O‐labelled water (H₂¹⁸O) revealed that a second enzymatic oxidation step occurs via the hydrate product intermediate. The relaxed substrate specificity, excellent enantioselectivity, and independence of coenzymes make AldO an attractive enzyme for the preparation of optically pure 1,2‐diols and α‐hydroxy acids.     

Survival, elongation, and elevated tolerance of Salmonella enterica serovar Enteritidis at reduced water activity

Growing microorganisms on dry surfaces, which results in exposure to low water activity (a(w)), may change their normal morphology and physiological activity. In this study, the morphological changes and cell viability of Salmonella enterica serovar Enteritidis challenged to low a(w) were analyzed. The results indicated that exposure to reduced a(w) induced filamentation of the cells. The amount of filamentous cells at a(w) 0.94 was up to 90% of the total number of cells. Surviving filamentous cells maintained their membrane integrity after exposure to low a(w) for 21 days. Furthermore, cells prechallenged to low a(w), obtained with an ionic humectant, demonstrated higher resistance to sodium hypochlorite than control cells. These resistant cells are able to survive disinfection more efficiently and can therefore cause contamination of foods coming in contact with surfaces. This points to the need for increased attention to cleaning of surfaces in household environments and disinfection procedures in processing plants.     

Enhanced visualization of histological samples with an adjustable RGB contrast system with application for tissue used in photodynamic therapy

The analysis of histological sections has long been a valuable tool in the pathological studies. The interpretation of tissue conditions, however, relies directly on visual evaluation of tissue slides, which may be difficult to interpret because of poor contrast or poor color differentiation. The Chromatic Contrast Visualization System (CCV) combines an optical microscope with electronically controlled light-emitting diodes (LEDs) in order to generate adjustable intensities of RGB channels for sample illumination. While most image enhancement techniques rely on software post-processing of an image acquired under standard illumination conditions, CCV produces real-time variations in the color composition of the light source itself. The possibility of covering the entire RGB chromatic range, combined with the optical properties of the different tissues, allows for a substantial enhancement in image details. Traditional image acquisition methods do not exploit these visual enhancements which results in poorer visual distinction among tissue structures. Photodynamic therapy (PDT) procedures are of increasing interest in the treatment of several forms of cancer. This study uses histological slides of rat liver samples that were induced to necrosis after being exposed to PDT. Results show that visualization of tissue structures could be improved by changing colors and intensities of the microscope light source. PDT-necrosed tissue samples are better differentiated when illuminated with different color wavelengths, leading to an improved differentiation of cells in the necrosis area. Due to the potential benefits it can bring to interpretation and diagnosis, further research in this field could make CCV an attractive technique for medical applications.     

Biological sulphate removal in an upflow packed bed reactor

Mine waters and industrial effluents with high sulphate concentrations create a disposal problem in terms of excess mineralization of surface waters. Removal of sulphate can be achieved by various processes including biological techniques, all of which involve appreciable costs. The purpose of this investigation was to improve on known biological methods for the removal of sulphate. Good sulphate removal was obtained by providing anaerobic conditions on a solid medium and maintaining a low hydrogen sulphide concentration by recirculating the water through a photosynthetic reactor for sulphur production.     

Chemisorption measurements on polymer‐stabilized colloidal platinum and rhodium nanoclusters in liquid dispersion

A simple method is reported for the precise and accurate differential barometric measurement of gas adsorption into liquid dispersions of colloidal metal catalysts. Using both hydrogen adsorption and hydrogen/oxygen titration the fraction of the total surface of polyvinylpyrrolidone‐stabilised Pt and Rh colloids available for adsorption is found to be approximately 44%. This method is also applicable to supported metal catalysts in liquid slurries. This revised version was published online in July 2006 with corrections to the Cover Date.     

Thermal crosslinked and nanodiamond reinforced SPEEK composite membrane for PEMFC

SPEEK has been widely considered as a promising alternative to Nafion^® membrane for PEMFC. However, a conflict between high degree of sulfonation (DS) and poor mechanical strength needs to be resolved prior to wide application. In this work, such an effort was made by double strategies: thermal crosslinking and adding nanodiamond into high DS SPEEK matrix. The obtained sample was characterized by XRD, high resolution TGA and dynamic mechanical analysis (DMA). Small part of –SO₃H groups within SPEEK matrix participated in the crosslinking process by forming –SO₂– bridge bond, while the rest large part of –SO₃H groups still contributed to the proton transport. Mechanical and thermal stability of SPEEK membrane were modified by crosslinking-induced three-dimensional (3D) networks and interactions of SPEEK with nanodiamond. In addition, the water uptakes of composite membranes were also slightly improved possibly due to the capillary condensation in nanodiamond particles.