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151.
2 studies of word learning are reported. In Study 1, 24-month-old children and 2 adults played with 3 nameless objects. These objects were placed in a clear box along with a novel nameless object. The adults then displayed excitement about the contents of the box and modeled a new word. Comparison with a control condition indicated significant learning of the new word for the novel object. Study 2 followed the same procedure with one difference: the children played with the novel object while the adults were absent. Thus, at the time of the language model the target object was novel only to the adults, not to the children. Again subjects displayed significant learning of the new word. This last finding suggests that 24-month-old children understand that adults use language for things that are novel to the discourse context and that this novelty is determined from the speaker's point of view. 相似文献
152.
The general nature of constructivist educators' views of teaching are overviewed first, followed by analysis of good strategy instruction in constructivist terms. That good strategy instruction is scaffolded teaching is particularly emphasized. Scaffolded teacher-student interactions necessitate that students experience unique instruction that stimulates a great deal of student construction of to-be-acquired competencies. The only important difference between good strategy teaching and teaching recommended by constructivist educators is in the explicitness of instruction, with relatively greater teacher input about what is to be learned during good strategy instruction. 相似文献
153.
Assessing Marital Conflict from the Child''s Perspective: The Children''s Perception of Interparental Conflict Scale 总被引:10,自引:0,他引:10
Guided by Grych and Fincham's theoretical framework for investigating the relation between interparental conflict and child adjustment, a questionnaire was developed to assess children's views of several aspects of marital conflict. The Children's Perception of Interparental Conflict Scale (CPIC) was initially examined in a sample of 222 9-12-year-old children, and results were cross-validated in a second sample of 144 similarly aged children. 3 factor analytically derived subscales (Conflict Properties, Threat, Self-Blame) demonstrated acceptable levels of internal consistency and test-retest reliability. The validity of the Conflict Properties scale was supported by significant relations with parent reports of conflict and indices of child adjustment; the Threat and Self-Blame scales correlated with children's responses to specific conflict vignettes. The CPIC thus appears to be a promising instrument for assessing perceived marital conflict, and several issues regarding its interpretation are discussed. 相似文献
154.
155.
Stress Reactivity and Self-Recognition 总被引:1,自引:0,他引:1
This study examined longitudinally whether early differences in reactivity to stress are related to self-recognition at 18 months of age. Adrenocortical and behavioral to Stress responses to routine inoculation at 2, and 4 months and at 6 and 18 months were obtained. Previous finding indicated a development shift in adrenocortical functioning by 6 months of age that included the emergence of stable individual differences in cortisol response from this point in development. Self-recognition was related to greater cortisol response and less rapid quieting at 6 to 18 months, whereas 2- to 4-month cortisol and quieting response did not differentiate self-recognizers and non-self-recognizators. These findings indicate a role for temperament differences in facilitating the emergence of self-recognition. 相似文献
156.
Salmanzadeh A Kittur H Sano MB C Roberts P Schmelz EM Davalos RV 《Biomicrofluidics》2012,6(2):24104-2410413
Ovarian cancer is the leading cause of death from gynecological malignancies in women. The primary challenge is the detection of the cancer at an early stage, since this drastically increases the survival rate. In this study we investigated the dielectrophoretic responses of progressive stages of mouse ovarian surface epithelial (MOSE) cells, as well as mouse fibroblast and macrophage cell lines, utilizing contactless dielectrophoresis (cDEP). cDEP is a relatively new cell manipulation technique that has addressed some of the challenges of conventional dielectrophoretic methods. To evaluate our microfluidic device performance, we computationally studied the effects of altering various geometrical parameters, such as the size and arrangement of insulating structures, on dielectrophoretic and drag forces. We found that the trapping voltage of MOSE cells increases as the cells progress from a non-tumorigenic, benign cell to a tumorigenic, malignant phenotype. Additionally, all MOSE cells display unique behavior compared to fibroblasts and macrophages, representing normal and inflammatory cells found in the peritoneal fluid. Based on these findings, we predict that cDEP can be utilized for isolation of ovarian cancer cells from peritoneal fluid as an early cancer detection tool. 相似文献
157.
In this paper, we focus on the potential innovative benefits to corporate venture capital (CVC), i.e. equity investments in entrepreneurial ventures by incumbent firms. We propose that corporate venture capital programs may be instrumental in harvesting innovations from entrepreneurial ventures and thus an important part of a firm's overall innovation strategy. We hypothesize that these programs are especially effective in weak intellectual property (IP) regimes and when the firm has sufficient absorptive capacity. We analyze a large panel of public firms over a 20-year period and find that increases in corporate venture capital investments are associated with subsequent increases in firm patenting. 相似文献
158.
159.
Dylan Poulsen Michael Defoort Mohamed Djemai 《Journal of The Franklin Institute》2019,356(16):9076-9094
We consider the leader–follower consensus problem for a multi-agent system where information is exchanged only on a non-uniform discrete stochastic time domain. For a second-order multi-agent system subject to intermittent information exchange, we model the tracking error dynamics as a varying linear system on a discrete stochastic time scale, where μ is the graininess operator. Based on a Lyapunov operator and a positive perturbation operator on the space of symmetric matrices, we derive necessary and sufficient conditions to design a decentralized consensus protocol. This protocol allows us to cast the mean-square exponential consensus problem within the framework of dynamic equations on stochastic time scales. We establish some theoretical results which allow for the computation of the control gain matrix which guarantees the mean-square exponential stability with a given decay rate for the error dynamics. To show the effectiveness of the theoretical results, some simulation and experimental results on multi-robot systems have been performed. 相似文献
160.