Advancing educational research on collaboration through the use of gStudy computer-supported collaborative learning (CSCL) tools: Introduction to special issue

This is an introduction to a special issue on computer-supported collaborative learning.     

Effect of instant controlled pressure drop on the oligosaccharides, inositol phosphates, trypsin inhibitors and lectins contents of different legumes

Well-controlled technologies for seed treatment have become a necessity for the food industry. Instant controlled pressure drop treatment (DIC®) is a new and highly controlled process that combines steam pressure (up to 8 bar) with heat (up to 170 °C) for a short time (up to 3 min). The end-product is a whole seed with a porous texture. The aim of this work was to evaluate the effect of this new (DIC) process on the contents of nutritionally active factors (NAF_s) in soybean, lupin, lentil, chickpea and roasted peanut. Unprocessed (control) and processed (DIC treatment under different pressure and time conditions) ground samples were analysed for oligosaccharides, inositol phosphates, trypsin inhibitors and lectins. The effect of DIC treatment on NAF_s in legume seeds has shown that this process considerably reduces most of these components; the optimum condition for DIC treatment in all the seeds was DIC-3 (6 bar, 1 min). The main advantages of DIC are its short processing time and the possibility of treating whole seeds for industrial applications.     

Helena Antipoff (1892–1974): A synthesis of Swiss and Soviet psychology in the context of Brazilian education.

Helena Antipoff played an important role in the development of a sociocultural perspective in educational psychology in Brazil. Drawing on her previous training in Paris, Geneva, and Petrograd, she proposed an original explanation for the high rates of school failure in the public system, from 1929 onward, when she became chairwoman of one of the first laboratories of psychology established in the country. This article focuses on her work, divided into 3 periods: the experience in Europe (1909–1929), the critique of the public educational system in Brazil (1929–1945), and the proposal of alternatives (1945–1974). Her contribution to the analysis of the development of intellectual skills in children, based on cultural and environmental factors, is related to the influence of Genevan interactionists and of Soviet cultural–historical theory, within the context of a critical view of the Brazilian educational system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sustainability in bridge construction processes

Sustainability must be seen as a global issue. In order to achieve that goal, it is necessary to apply its principles to all industrial activities, including those that are not traditionally engaged with such guidelines, which is the case of Bridge Construction. This paper evaluates the consumption of steel and energy and the emissions of carbon dioxide due to the use of movable scaffolding systems (MSS) in the Bridge Construction industry. The values obtained considering the use of conventional MSS are compared with the ones obtained using a new sustainable technology which is herein synthetically described—the organic prestressing system (OPS). In order to compare the sustainability of the two systems, a prediction of the material and energy consumptions, and CO₂ emissions for traditional MSS and for MSS equipped with OPS is performed until 2025.     

Shelf-Life Extension of Fresh Tuber aestivum and Tuber melanosporum Truffles by Modified Atmosphere Packaging with Microperforated Films

ABSTRACT: The aim of this study was to design a modified atmosphere packaging suitable for Tuber melanosporum and Tuber aestivum truffles that extend their shelf life and their availability as a fresh product. Their respiration rates were determined by O₂ depletion and CO₂ formation in closed systems performed at different temperatures: 4, 10, and 23 °C. The results were fitted by exponential equations and derivatives of these equations were used to obtain the experimental respiration rates. Our results revealed high respiration rates in both species of truffles and respiratory quotients (RQ) higher than 1 in all the cases studied. A linear dependence of respiration rate, both R_O2 and R_CO2, on O₂ concentration was revealed. A mathematical model was used to predict the evolution of the gaseous composition at 4 °C in the interior of polypropylene trays (250 mL) heat sealed with 4 microperforated films of different transmission rates. A microperforated film with 2 holes (90 × 50 μm) was selected to produce an internal atmosphere of 15%CO₂/7%O₂ at 4 °C. The predicted atmosphere composition was confirmed by the experimental results. The quality and microbiological characteristics of fresh truffles, packaged in these conditions, revealed that the microbial counts of pseudomonads and Enterobacteriaceae were decreased, the weight loss was reduced, the typical hard texture was maintained, and the development of mycelium growth was delayed, enabling good scores for aroma and flavor, and therefore prolonging the shelf life of T. melanosporum and T. aestivum truffles to 28 and 21 d, respectively. Practical Application: This study describes the benefits of using MAP with microperforated films in the postharvest storage of Tuber melanosporum and Tuber aestivum fresh truffles. The shelf life of T. aestivum is prolonged to 21 d and of T. melanosporum to beyond 28 d increasing the possibilities for a foreign market.     

Development and validation of an attributional style questionnaire for adolescents.

We describe the development and psychometric characteristics of a new version of the Attributional Style Questionnaire (ASQ; Seligman, Abramson, Semmell, & Von Baeyer, 1979)—a version called the Attributional Style Questionnaire for Adolescents (ASQ-A)—using 3 samples (Ns = 547, 438, and 240) of Spanish secondary school students. In Study 1, the initial pool of 87 items was reduced to 54. Study 2 further analyzed the 54 scale items and revealed that the Internality, Stability, and Globality subscale scores had good reliability, good factorial construct validity, and satisfactory associations with maladaptive mood ratings. In Study 3, the regression analyses showed good and specific predictive validities of ASQ-A subscales for the attributions that the adolescents made about a particular real-life stressful situation. Study 4 showed that over an 8-month period the changes in the Stability and Globality subscales depended on the intensity of stressful life events experienced in this period. Overall, the studies revealed that the new ASQ-A served as an appropriate instrument to assess attributional style in adolescents. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Doping of lanthanum cobaltite by Mn: thermal,magnetic, and catalytic effect

Great differences in crystallographic phases, magnetic properties, and catalytic activity were detected in lanthanum cobaltite and cobaltite modified with the insertion of 10 wt.% of Mn. Atomic absorption spectroscopy, BET area measurements, XRD analysis, TPR, and FT-IR suggest that the total insertion of manganese in the LaCoO₃ structure is successful. Thermal stability is reached for LaCo_0.90Mn_0.10O₃ up to 973 K without loss of the perovskite structure. The magnetic properties of the as-grown compounds are maintained after a first reduction process up to 723–773 K, while presence of segregated phases is observed after reduction at 973 K. The catalytic activity evaluated in the total combustion of acetyl acetate shows a decrease in the ignition temperature, i.e. an increase in the catalytic activity for the LaCo_0.90Mn_0.10O₃ perovskite. A significant enhancement in the catalytic activity expressed as intrinsic activity, mol m⁻² h⁻¹, with the manganese substitution was found.     

Polyurethane-acrylate based films as humidity sensors

Fluorescence spectroscopy, together with a conventional gravimetric method, were employed to study the mechanism and kinetics of water diffusion in UV-cured polyurethane-acrylate based adhesive films doped with organic fluorescent sensors. The diffusion of water through the films followed Fick's law during almost the whole mass sorption curve. Whilst the fluorescence data showed that boundary conditions are more complex and Fickian behaviour is only observed after different periods, depending on the molar volume of the fluorescent probe and the adhesive composition. The influence of hydrophilic monomers is discussed. Good correlation between diffusion coefficients by both methods is obtained in the range where water uptake is diffusion controlled.

The fluorescence of the studied probes or labels in these films shows high sensitivity to humidity, good long-term stability and fast response time. Therefore, it appears that these doped films can be used as efficient humidity sensors.     

Review of The Causes of Rape: Understanding Individual Differences in Male Propensity for Sexual Aggression.

Reviews the book, The Causes of Rape: Understanding Individual Differences in Male Propensity for Sexual Aggression by Martin L. Lalumière, Grant T. Harris, Vernon L. Quinsey and Marnie E. Rice (see record 2005-00308-000). This text presents an evolutionary explanation for rape, closely related to the writings of people like Wilson and Ellis, with which many readers will be familiar. It develops an argument that rape is a "mating effort" closely associated with "antisociality." If using an evolutionary framework to understand rape does not appeal to you, stop here. But if you are interested in its "sex appeal," this book is interesting. How so? Like other psychobiological writings, it explains the status quo using a carefully selected body of scientific empirical studies that supports their argument... And, overlooking some shortcomings, it does it well! (PsycINFO Database Record (c) 2010 APA, all rights reserved)