排序方式： 共有15条查询结果，搜索用时 687 毫秒
1.
Employing an experimental design, mother-to-infant transmission of stress was examined. Mothers (N = 117) were randomized to either have a positive or conflictual discussion with their marital partners, after which infants (age = 6 months) participated in a fear and frustration task. Saliva samples were collected to assess maternal cortisol responses to the discussion and infant cortisol responses to the challenge task. Results indicate maternal cortisol reactivity and recovery to the conflict (but not positive) discussion predicted infant cortisol reactivity to the infant challenge. Mothers’ positive affect during the discussion buffered, and intrusion during the free-play potentiated, mother-to-infant adrenocortical transmission. These findings advance our understanding of the social and contextual regulation of adrenocortical activity in early childhood. 相似文献
2.
This paper is aimed to investigate the operating characteristics of a static synchronous compensator (STATCOM) integrated with superconducting magnetic energy storage (SMES) for high power applications in the transmission network level. The STATCOM controller topology comprises multi-level multi-pulse neutral-point clamped-type (NPC) voltage source inverters (VSIs) using the harmonics cancellation technique, and incorporates a SMES coil. An innovative two-quadrant multi-level dc-dc converter is proposed to effectively interface the STATCOM with the superconducting coil using a buck-boost topology with neutral point voltage control capabilities; thus enabling to simultaneously control both active and reactive power exchange with the high voltage power system. A detailed analysis of major system variables is presented, including analytical results and digital simulations using the MATLAB/Simulink environment. Moreover, a three-level control scheme is designed, including a full decoupled current control strategy in the d-q reference frame with a novel controller to prevent the STATCOM dc bus capacitors voltage drift/imbalance and an enhanced power system frequency controller. 相似文献
3.
Teacher preparation programs face a significant challenge in determining how to design learning experiences that develop the combination of knowledge, practices, and dispositions needed for effective classroom teaching. Time constraints and the theory–practice divide are two well-documented concerns. We introduce the conceptual framework and design elements of a video-enhanced mathematics methods course that targets these concerns. The course centers on systematic reflection and analysis of practice intended to foster career-long learning. We then examine the impact of this course on several facets of learning-from-teaching competencies, including teacher knowledge, beliefs, and practices. Sixty-two preservice teachers enrolled in a one-year post-bachelor elementary teacher preparation program were randomly assigned to attend this course or a more typical mathematics methods course. Findings suggest that teacher preparation experiences centered on systematic reflection and analysis create opportunities to develop certain aspects of learning-from-teaching competencies that remain otherwise underdeveloped. Implications for the design of teacher preparation include the integration in mathematics methods courses of cycles of analysis through video-enhanced discussions; collaborative planning, implementation, and reflection on teaching; and live observation and co-constructed interpretations and considerations of next steps. 相似文献
4.
Eduardo Mercado Scott O. Murray Robert K. Uyeyama Adam A. Pack Louis M. Herman 《Learning & behavior》1998,26(2):210-218
Little is known about how animals represent their own actions in working memory. We investigated whether bottlenosed dolphins could recall actions they had recently performed and reveal those recollections using an abstract rule. Two dolphins were trained to respond to a specific gestural command by repeating the last behavior performed. Both dolphins proved to be able to repeat a wide variety of behaviors on command and were able to generalize the repeating rule to novel behaviors and situations. One dolphin was able to repeat all 36 behaviors she was tested on, including behaviors involving multiple simultaneous actions and self-selected behaviors. These results suggest that dolphins can flexibly access memories of their recent actions and that these memories are of sufficient detail to allow for reenactments. The repeating task can potentially be used to investigate short-term action and event representations in a variety of species. 相似文献
5.
6.
Antonieta Mercado 《Communication Teacher》2019,33(2):94-98
This activity highlights the concept of cultural hegemony, illustrating it by a reflection on the images of success and successful people portrayed in the media. The purpose of the exercise is to introduce students to this concept, and for them to examine how hegemonic views of others and the self affect the way they conceptualize success and perceive who a successful person is. Students will understand the role of the media in reproducing hegemonic representations of reality in terms of gender, race, ethnicity, national origin, disability, and so on, and how these representations limit their world view and are detrimental for those who do not abide by the dominant stereotypical images. The exercise also intends to expose students to complex narratives of what success may mean beyond accumulation of wealth, competition, nationality, whiteness, and patriarchal values, and for them to reflect upon intersectionality, by challenging and critiquing dominant portrayals of human achievement.
Courses: Introduction to Media Studies, Introduction to Media and Culture, or any introductory communication course discussing media representation.
Objectives: Students will (1) identify the role of cultural hegemony in the mediated construction of success; (2) understand and critically evaluate how hegemonic media representations of gender, class, race, ethnicity, physical ability, national origin, and so on limit people’s world views about human achievement; and (3) self-reflect on their own representations of success and reframe “success” moving beyond hegemonic representations attached to patriarchy, heteronormativity, whiteness, physical ability, competition, and capitalist accumulation. 相似文献
7.
Learning to discriminate stimuli can alter how one distinguishes related stimuli. For instance, training an individual to
differentiate between two stimuli along a single dimension can alter how that individual generalizes learned responses. In
this study, we examined the persistence of shifts in generalization gradients after training with sounds. University students
were trained to differentiate two sounds that varied along a complex acoustic dimension. The students were subsequently tested
on their ability to recognize a sound that they had experienced during training when it was presented among several novel
sounds varying along this same dimension. Peak shift was observed in Experiment 1, in which generalization tests immediately
followed training, and in Experiment 2, in which the tests were delayed by 24 h. These findings further support the universality
of generalization processes across species, modalities, and levels of stimulus complexity. They also raise new questions about
the mechanisms underlying learning-related shifts in generalization gradients. The sound stimuli from this study are available
as .wav files from http://lb.psychonomic-journals.org/content/supplemental. 相似文献
8.
Tim Bond Courtland C. Lee Ruth Lowe A. E. Margarita Malayapillay Sue Wheeler Angela Banks Kathryn Kurdt Melissa M. Mercado Elizabeth Smiley 《International journal for the advancement of counseling》2001,23(4):245-260
The purpose of this study was to investigatecounselling as a process. It was conducted toexplore whether counselling is available invarious countries, even if it is known byanother name. This study examined the kinds ofhelp available to people with specificdifficulties. It sought to discern whether theways of helping include activities that mightbe thought of as counselling. As a way todiscover what forms of help might be availableto people in a given country, a series ofstressful incidents confronting one family ofaverage income living in a large town weredeveloped into a questionnaire format. Theseincidents were designed to stimulate thinkingand focus attention on possible help-givingsources. Data were collected from sources infifteen countries through interviews atinternational counselling conferences and withselected embassy officials in Washington, D.C.Interviews were also conducted in the UnitedKingdom, the United States, Costa Rica, andMalaysia. In addition, questionnaires were sentto experts knowledgeable about social welfareissues in a number of countries. The findingsfrom this investigation suggest thatcounselling as an activity or a process may betaking place under different names in differentcultures. 相似文献
9.
10.
This paper presents a taxonomy of entrepreneurial behaviour vis-à-vis technology, derived from empirical research on a specific sector, that of the chemicals industry in Venezuela. The research focuses heavily on the accumulation of minor innovations through which enterprises acquire their technical knowledge and know how, their technological learning. We have tried to give a precise empirical meaning to that notion in order to understand which are the most important variables that affect the technical learning process. Both the process of technological learning and the technical external linkages — in particular with foreign firms — of Venezuelan companies seem to be the fundamental factors in understanding the development of a new competitive industry which adopts a new products-oriented strategy. But not all firms do respond to such a scheme and it is thus necessary to develop a taxonomy of the industrial sector both for scholarly reasons as well as a policy guide. 相似文献