Training and assessing numerical abilities across the lifespan with intelligent systems: The example of Baldo

Baldo is an intelligent system that can be used to assess and train numerical abilities across the lifespan, especially for children and elderly. Baldo includes digital and tangible materials to propose activities, built on the game-based learning approach, strongly grounded on well-known and experimentally supported theories about numerical and mathematical cognition. Moreover, Baldo has a special module devoted to motivational and affective dimensions related to mathematic cognition and a tutoring system to select specific activities that are adequate to the actual and potential level of the people involved in the training pathway.     

Cross-cultural and cognitive issues in the implementation of new technology: focus on group support systems and Bulgaria

Over 40 per cent of technology implementation attempts in the United States (US) fail. These failures often are the result of human (rather than technological) problems. The consequences of implementers installing in one country equipment designed in another should be even more problematic and ubiquitous, as technology designers continue to move into international markets. A cognitive model of cross-cultural implementation is tested, using a US-designed group support system (GSS) and groups of Bulgarian and US university students. Bulgarians were expected to be less critical of the technology due to cultural responses to power and authority (i.e., less likely to challenge authority) and therefore less successful in adapting to the technology. However, results suggest that the Bulgarian students may in fact be more likely to challenge authority than their US counterparts. As hypothesized, Power Distance mediates some of the effects between culture and satisfaction with the GSS.     

Variational techniques for assessing the technological signature of flat surfaces

The quality assessment of manufacturing operations performed to obtain given flat surfaces is always a problem of comparing the substitute model (approximating the features of the true manufactured part) to the nominal specifications, at any stage of the manufacturing cycle. A novel methodology, based on applications of classical tools of Calculus of Variations, is here presented with the aim of assessing the output quality of manufactured flat surfaces based on the information available on transformation imposed by technological processes. By assuming that any manufacturing process operates under equilibrium states, the proposed variational methodology allows to account for the traces left by different stages of manufacturing processes. A simple two-dimensional case is here discussed, to give the flavor of the methodology and its future potential developments.     

Teacher beliefs about instructional choice: A phenomenological study.

We interviewed 36 practicing teachers, using phenomenological methods to examine what, when, where, and to whom teachers offer choice. Teachers participated in pilot, interview, and member-check phases. Our final results focused on the following main points: (a) Teachers believe that choice promotes learning and motivation; (b) choice is used in a number of ways; (c) teachers have a variety of reasons for giving choices; and (d) teachers imposed limits on classroom choice based on (e) student age, ability, and prior knowledge and (f) teacher experience, efficacy, and management style. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Energy and environmental analysis of glass container production and recycling

This work aims at examining, from an energy and environmental standpoint, one production cycle which is extremely energy-consuming, namely the glass production for drink containers. More specifically, the industrial process is first analysed as is, so as to evaluate and assess its energy needs and its associated environmental impact. As a second step the influence of glass container recycle and reuse on energy consumption and pollutant emission is investigated. To this end the recycling chain operation is illustrated and appropriate working hypotheses for the modified process are formulated, so that its energy and environmental performance can be evaluated. Finally, the two production scenarios are compared by means of LCA (Life Cycle Assessment) methodology, to the purpose of determining the best recycling percentage for glass containers from the standpoint of energy consumption and pollutant emission minimization, taking also into account the waste legislation currently in force.     

Assessing the role of the growth hormone secretagogue receptor in motivational learning and food intake.

The orexigenic neuropeptide ghrelin is an endogeneous ligand for the growth hormone secretagogue receptor (GHS-R). This orexigen is expressed in both the periphery and in the central system, including portions of mesolimbic dopaminergic circuitry that play a role in affective behaviors. Here we examined pharmacological antagonism of GHS-R in motivational incentive learning, as reflected in Pavlovian-to-instrumental transfer (PIT). Furthermore, it is currently unclear whether the previous effects of ghrelin on food intake are mediated by pre- and/or postingestive influences on ingestive behavior. Thus, the authors also conducted detailed analyses of the temporal dynamics of sucrose licking. Mice received low (50 nmol), moderate (100 nmol), and high (200 nmol) intraperitoneal injections of the GHS-R antagonist GHRP-6 [D-Lys3] prior to subsequent transfer and sucrose consumption tests. Low and moderate doses led to an augmentation of PIT, while high dose injections led to generalized performance deficits. In addition, moderate and high doses of the antagonist resulted in reductions in sucrose intake by reducing palatability of the sucrose. These results suggest dissociable functions of GHS-R in its influence over motivational learning and ingestive behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Redox behavior of gold supported on ceria and ceria-zirconia based catalysts

A series of gold-based catalysts were prepared by deposition precipitation or incipient wetness impregnation on CexZ1-xO2 solid solutions (0.28≤x≤1.00). The morphological and structural characterization of these catalysts were carried out with X-ray diffraction, trans-mission electron microscopy (TEM) analysis and physical adsorption technique, and their redox properties were studied by temperature pro-grammed reduction using both H2 and CO as probe molecules. Two cycles of oxidation/reduction were carried out in order to evaluate the effects of redox aging and gold sintering on the oxygen exchange capability. As observed with other noble metals, gold enhanced and pro-moted the ceria reduction at lower temperatures. Reduction by CO was shown to be dependent on the fine dispersion of gold and to be nega-tively affected by the ageing process more than reduction with hydrogen. This might have implications in reactions like water gas shift and CO-PROX which involve CO as a main reactant.     

Behavior of BaCe0.9−x Zr x Y0.1O3−δ in water and ethanol suspensions

The stability of perovskite proton conductors BaCe_0.2Zr_0.7Y_0.1O_2.95 and BaCe_0.5Zr_0.4Y_0.1O_2.95 (referred to as BCZY) has been tested by exposure of powders to water and ethanol at room temperature. The liquid phase was monitored as a function of time with inductively coupled plasma-optical emission spectrometry. With water, leaching of barium continued for over 200 days, the duration of the test. There was no systematic difference in leaching with solutions of native pH or alkalified with NH₄OH. The powders, before and after treatment, were investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). TEM confirmed the degradation of the perovskite phase and revealed barium carbonate nanobranches and nanoparticles from the agglomeration of the fragmented perovskite. The effect of ethanol was much less severe; leaching of elements after immersion was negligible for up to 17 days, and XRD patterns before and after treatment did not show any structural degradation. It is concluded that ethanol is an appropriate choice as a processing solvent for tapecasting BCZY powders.