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91.
Why people benefit from e-learning differently: The effects of psychological processes on e-learning outcomes 总被引:1,自引:0,他引:1
Using social cognitive theory, we opened up the black box of psychological processes in which e-learners engage. We believed that prior experience with ICT and virtual competence were two influential factors that affected e-learning and had a positive influence on its outcomes. We tested our hypotheses on a sample of 383 Chinese students participating in online courses. Our findings confirmed the effect of virtual competence and revealed a nuanced mechanism by which experiences with ICT affected e-learning outcomes. We discussed the implications of this in e-learning practice. 相似文献
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93.
Nicole M. van Dam Bao-Li Qiu Cornelis A. Hordijk Louise E. M. Vet Jeroen J. Jansen 《Journal of chemical ecology》2010,36(9):1006-1016
Plants under attack by aboveground herbivores emit complex blends of volatile organic compounds (VOCs). Specific compounds
in these blends are used by parasitic wasps to find their hosts. Belowground induction causes shifts in the composition of
aboveground induced VOC blends, which affect the preference of parasitic wasps. To identify which of the many volatiles in
the complex VOC blends may explain parasitoid preference poses a challenge to ecologists. Here, we present a case study in
which we use a novel bioinformatics approach to identify biologically relevant differences between VOC blends of feral cabbage
(Brassica oleracea L.). The plants were induced aboveground or belowground with jasmonic acid (JA) and shoot feeding caterpillars (Pieris brassicae or P. rapae). We used Partial Least Squares—Discriminant Analysis (PLSDA) to integrate and visualize the relation between plant-emitted
VOCs and the preference of female Cotesia glomerata. Overall, female wasps preferred JA-induced plants over controls, but
they strongly preferred aboveground JA-induced plants over belowground JA-induced plants. PLSDA revealed that the emission
of several monoterpenes was enhanced similarly in all JA-treated plants, whereas homoterpenes and sesquiterpenes increased
exclusively in aboveground JA-induced plants. Wasps may use the ratio between these two classes of terpenes to discriminate
between aboveground and belowground induced plants. Additionally, it shows that aboveground applied JA induces different VOC
biosynthetic pathways than JA applied to the root. Our bioinformatic approach, thus, successfully identified which VOCs matched
the preferences of the wasps in the various choice tests. Additionally, the analysis generated novel hypotheses about the
role of JA as a signaling compound in aboveground and belowground induced responses in plants. 相似文献
94.
Individual coping strategies and dyadic coping independently predict partner well-being and relationship functioning; however, it is unclear whether the coping processes are inter-related and whether they uniquely contribute to romantic relationship functioning. One hundred heterosexual dating couples rated the individual coping strategy of negative mood regulation as well as positive and negative dyadic coping. Relationship functioning was assessed via partners' reports of relationship satisfaction and observers' ratings of negative interaction in conflict. Actor-Partner Interdependence Models (APIMs; Cook & Kenny, 2005; Kashy & Kenny, 2000) revealed associations between individual coping and dyadic coping in the predicted directions. APIMs also indicated the unique contributions of positive and negative dyadic coping to relationship functioning, above and beyond contributions of individual coping strategies. Implications of dyadic coping as a target of efforts to prevent or treat partner and/or relational distress are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Oliver Köster-Scherger Herbert Schmid Nicole Vanderschaeghe Frank Wolf Werner Mader 《Journal of the American Ceramic Society》2007,90(12):3984-3991
Zinc oxide (ZnO) crystals with additions of iron (III) oxide exhibit a characteristic inversion domain microstructure with domain boundaries on two different habit planes: parallel to {0001} basal planes and parallel to {2 1 1 5} pyramidal planes of ZnO. The structural inversion of the domains is proved by electron diffraction experiments. In the present transmission electron microscopy study, emphasis is placed on the early stages of domain formation in sintered polycrystalline material and in diffusion couples with single crystals of ZnO. For solute iron content >0.5 at.% of the cations, defects nucleate at the surface and in the interior of ZnO grains at >900°C. These primary defects propagate along the basal planes of ZnO and gradually widen in the positive c -axis direction of the ZnO host crystal. The widening along c is promoted by a second defect on {2 1 1 l } planes that moves away from the basal plane defect. The c -axis orientation in the ZnO region swept by the second defect is inverted, finally resulting in the inversion domain microstructure. A low iron content ≈0.1 at.% was measured in the inverted domains. Energy-filtered imaging and quantitative electron energy-loss spectroscopy show that the inversion domain boundaries (IDBs) parallel to the basal planes contain a full close-packed monolayer of iron whereas the pyramidal IDBs are occupied by iron with ≈2/3 of the content of the basal IDB. Based on experimental observations and arguments of structural chemistry, a mechanism is proposed explaining the nucleation and oriented growth of the inversion domains that are finally induced and driven by the trivalent iron ions at octahedral sites in the primary defects. 相似文献
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97.
Two-, 3-, and 4-year-old children viewed 10 stimulus sets. Each set contained a sample picture (e.g., a dog), a basic-level taxonomic match (e.g., another dog), a thematic match (e.g., a bone), and an irrelevant match (e.g., a pen). The children were asked to choose a match that "goes with" each sample. Sample pictures were either animate entities or artifacts. The children's choice behavior indicated that a shift occurs between 3 and 4 years of age from a taxonomic bias to a thematic bias and that, at both ages, animate sample stimuli enhance the children's tendency to adopt thematic conceptual strategies. These data are consistent with recent suggestions that thematic thinking presupposes basic-level taxonomic thinking during early conceptual development and that this developmental progression occurs more rapidly in some domains of knowledge than in others. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
Rogers Richard; Sewell Kenneth W.; Grandjean Nicole R.; Vitacco Michael 《Canadian Metallurgical Quarterly》2002,14(2):177
Psychologists have standardized competency-to-stand-trial (CST) assessments through the development of specialized CST measures. However, their research has largely neglected the possibility that CST measures may be stymied by feigning mental disorders and concomitant impairment. The current study is the first systematic examination of (a) how feigned mental disorders may affect CST measures and (b) which scales are effective at identifying feigned cases. Bona fide patients (n=65) were compared with suspected malingerers (n=22) on 3 CST measures: the Georgia Court Competency Test (GCCT), the MacArthur Competence Assessment Tool-Criminal Adjudication, and the Evaluation of Competency to Stand Trial-Revised (ECST-R). Results indicated that these CST measures are vulnerable to feigning. The development of specialized GCCT and ECST-R scales yielded moderately effective screens for feigned mental disorders in the context of CST evaluations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Mouna Marrakchi Sergei V. Dzyadevych Florence Lagarde Claude Martelet Nicole Jaffrezic-Renault 《Materials science & engineering. C, Materials for biological applications》2008,28(5-6):872-875
This paper investigates the development of a biosensor associating two distinct enzymatic activities, that of the beta-galactosidase and that of the glucose oxidase, in order to apply it for the quantitative detection of lactose in milk. To eliminate interferences with glucose, a differential mode of measurement was used. Results show a linear calibration curve for lactose concentration between 60 and 800 μM (0.03 to 0.3 g/L). Tests with real commercial milk samples were carried out to validate the conductometric biosensor. 相似文献
100.
This study compares the effects of practice spelling and reading specific words on the orthographic representations in memory involved in reading both practiced words and new, unfamiliar words. Typically developing readers in Grade 2 (mean age = 7 years, 7 months) participated in a training study examining whether transfer can occur between reading and spelling following a series of reading and spelling practice sessions. Practice consisted of either repeated reading or repeated spelling of words with shared orthographic rime patterns. A series of mixed analyses of variance was used to examine generalization within skill and transfer across skill. Following practice, word-specific transfer across skill was found. Specifically, children were better able to spell words they had practiced reading and to read words they had practiced spelling. In addition, generalization to new words with practiced rime units was found both within a skill and across skills. However, transfer from spelling to reading was greater than transfer from reading to spelling. Results indicate that the orthographic representations established through practice can be used for both reading and spelling. Subsequently, reading and spelling curricula should be coordinated to benefit children maximally. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献