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Many argue that games can positively impact learning by providing an intrinsically motivating and engaging learning environment for students in ways that traditional school cannot. Recent research demonstrates that games have the potential to impact student learning in STEM content areas and that collaborative gameplay may be of particular importance for learning gains. This study investigated the effects of collaborative and single game player conditions on science content learning and science self-efficacy. Results indicated that there were no differences between the two playing conditions; however, when conditions were collapsed, science content learning and self-efficacy significantly increased. Future research should focus on the composition of collaboration interaction among game players to assess what types of collaborative tasks may yield positive learning gains. 相似文献
43.
Alberto Abad Anna Pompili Angela Costa Isabel Trancoso José Fonseca Gabriela Leal Luisa Farrajota Isabel P. Martins 《Computer Speech and Language》2013,27(6):1235-1248
One of the most common effects among aphasia patients is the difficulty to recall names or words. Typically, word retrieval problems can be treated through word naming therapeutic exercises. In fact, the frequency and the intensity of speech therapy are key factors in the recovery of lost communication functionalities. In this sense, speech and language technology can have a relevant contribution in the development of automatic therapy methods. In this work, we present an on-line system designed to behave as a virtual therapist incorporating automatic speech recognition technology that permits aphasia patients to perform word naming training exercises. We focus on the study of the automatic word naming detector module and on its utility for both global evaluation and treatment. For that purpose, a database consisting of word naming therapy sessions of aphasic Portuguese native speakers has been collected. In spite of the different patient characteristics and speech quality conditions of the collected data, encouraging results have been obtained thanks to a calibration method that makes use of the patients’ word naming ability to automatically adapt to the patients’ speech particularities. 相似文献
44.
The CuPS (Culture × Person × Situation) approach attempts to jointly consider culture and individual differences, without treating either as noise and without reducing one to the other. Culture is important because it helps define psychological situations and create meaningful clusters of behavior according to particular logics. Individual differences are important because individuals vary in the extent to which they endorse or reject a culture's ideals. Further, because different cultures are organized by different logics, individual differences mean something different in each. Central to these studies are concepts of honor-related violence and individual worth as being inalienable versus socially conferred. We illustrate our argument with 2 experiments involving participants from honor, face, and dignity cultures. The studies showed that the same “type” of person who was most helpful, honest, and likely to behave with integrity in one culture was the “type” of person least likely to do so in another culture. We discuss how CuPS can provide a rudimentary but integrated approach to understanding both within- and between-culture variation. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
45.
Angela Peterzol Philippe DuvauchelleValérie Kaftandjian Pascal Ponard 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,654(1):450-463
Energy-Dispersive X-ray Diffraction (EDXRD) is well suited for the detection of narcotics and a wide range of explosives. This technique, combined with the dual-energy tomosynthesis, has been used for verification of a novel portable imaging system, the aim of which is characterization of dangerous/illicit materials inside objects. We present the design methodology and optimization study using EDXRD modality. In order to evaluate the experimental conditions best suited for system purposes, kinematic theory of diffraction has been exploited to model the height and shape of diffraction patterns. From the simulation-based analysis a diffraction angle of 2.75°±0.10° and an X-ray tube voltage ≤160 kV have been selected. 相似文献
46.
The incorporation of phase change materials (PCMs) in building materials for use as latent heat storage and for potential reduction of energy requirements is an on-going field of study. In this paper, the development and testing of PCM-enhanced cellulose insulation for use in frame walls is presented. Two types of PCMs, paraffin-based and hydrated salt-based, were mixed into loose-fill cellulose insulation at concentrations of 10% and 20% (by the weight of the wallboard) in a 1.22 m × 1.22 m (48 in. × 48 in.) frame wall cavity. The thermally-enhanced frame walls were heated and allowed to cool down in a dynamic wall simulator that replicated the sun's exposure in a wall of a building on a typical summer day. Peak heat fluxes, total “daily” heat flows, and surface and air temperatures were measured and recorded. Results show that the paraffin-based PCM-enhanced insulation reduced the average peak heat flux by up to 9.2% and reduced the average total “daily” heat flow up to 1.2%. Because of the hydroscopic behavior of un-encapsulated hydrated salt, the hydrated salt-based PCM-enhanced insulation did not provide any thermal storage benefit. 相似文献
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48.
Incompatible land use is a major contributor to ecosystem degradation, and is often exacerbated by climate change impacts. We investigate Lake Basotu, Tanzania as a case study where natural lake variability has been affected by agricultural land use. Comparisons between a satellite-derived history of lake surface area, local precipitation records, and corresponding anthropogenic activity show the impacts of agricultural and historical practices. We argue that insufficient consideration to the wider ecological impacts of large agricultural projects has lasting implications. This is particularly true in semi-arid environments where food production demands need to be continuously met. In the future, major conservation strategies should be investigated to maintain the environmental integrity and sustainability of freshwater resources. 相似文献
49.
A history of land clearance and riparian tree and wood management has resulted in limited riparian woodland and wood along British rivers. However, river management approaches are now being promoted that ‘work with natural processes’ to reduce flood risk through measures intended to restore, protect and emulate the natural function of catchments, rivers, estuaries and coasts. Wood has started to be reintroduced into river channels during river restoration and natural flood management activities, but this needs to be undertaken using appropriate quantities, locations and designs that mimic natural tree‐wood features. This paper reviews the knowledge that is needed to support wood reintroduction activities including (i) the characteristics of the riparian tree species and wood that are present; (ii) the importance of river size relative to that of trees and wood pieces; and (iii) the way trees, wood and geomorphic processes interact across rivers and floodplains of different energy and style. 相似文献
50.
Angela Lanciotti Maria Stefania Brignone Pompeo Macioce Sergio Visentin Elena Ambrosini 《International journal of molecular sciences》2022,23(1)
Astrocytes are very versatile cells, endowed with multitasking capacities to ensure brain homeostasis maintenance from brain development to adult life. It has become increasingly evident that astrocytes play a central role in many central nervous system pathologies, not only as regulators of defensive responses against brain insults but also as primary culprits of the disease onset and progression. This is particularly evident in some rare leukodystrophies (LDs) where white matter/myelin deterioration is due to primary astrocyte dysfunctions. Understanding the molecular defects causing these LDs may help clarify astrocyte contribution to myelin formation/maintenance and favor the identification of possible therapeutic targets for LDs and other CNS demyelinating diseases. To date, the pathogenic mechanisms of these LDs are poorly known due to the rarity of the pathological tissue and the failure of the animal models to fully recapitulate the human diseases. Thus, the development of human induced pluripotent stem cells (hiPSC) from patient fibroblasts and their differentiation into astrocytes is a promising approach to overcome these issues. In this review, we discuss the primary role of astrocytes in LD pathogenesis, the experimental models currently available and the advantages, future evolutions, perspectives, and limitations of hiPSC to study pathologies implying astrocyte dysfunctions. 相似文献