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排序方式: 共有291条查询结果,搜索用时 15 毫秒
21.
Kyle S. Wiley Molly M. Fox Theresa E. Gildner Zaneta M. Thayer 《Child development》2023,94(5):1356-1367
Infant social–emotional development may be impacted by the COVID-19 pandemic. This study investigated associations between maternal pre- and postnatal pandemic-related concerns and social–emotional developmental risk. Data, collected in 2020–2021, came from 220 mothers (87% white, 6% Hispanic, 1% Black, 3% Asian, 1% American Indian, Mage = 32.46 years), and infants (53.18% male, Mage = 12.98 months) in the United States. Maternal postnatal pandemic-related concerns were associated with total risk scores (B = 6.09, p-value <.001) and offspring risk of scoring positive for problems related to inflexibility (B = 4.07, p-value = .006). The total score association was moderated by self-reported social support. Infants may be detrimentally impacted by the pandemic via maternal pandemic-related concerns. Maternal social support may buffer infants. 相似文献
22.
Clark A. Chinn Susan A. Yoon Huma Hussain-Abidi Kyle Hunkar Noora F. Noushad Amanda M. Cottone Thomas Richman 《European Journal of Education》2023,58(3):407-421
An important goal of science education is promoting scientific literacy—the competence to interact with science as laypeople to solve problems and make decisions in their personal and community lives. This is made more challenging in an age of increasing science denialism. In this article, we discuss how to design learning environments for science education that can help students attain scientific literacy. We argue that science curricula should encompass lessons with two distinguishable foci. One focus engages students in understanding the reliability of science. The second focus engages students as laypeople interacting with science in the public sphere. We discuss these two curricular foci, presenting examples from our own work on designing and implementing instruction with the first focus. 相似文献
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Empowering Marginalized Youth: A Self‐Transformative Intervention for Promoting Positive Youth Development
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Kyle Eichas Marilyn J. Montgomery Alan Meca William M. Kurtines 《Child development》2017,88(4):1115-1124
This article reports the results of a positive youth development (PYD) intervention for adolescents in alternative high schools (209 African American and Hispanic American adolescents, aged 14–18; 118 females and 91 males). The intervention was guided by a self‐transformative model of PYD (Eichas, Meca, Montgomery, & Kurtines, 2014). This model proposes that the actions youth take to define themselves function as active ingredients in positive development over the life course. Consistent with the self‐transformative model, results provided support for direct or mediated intervention effects on the self‐transformative processes of self‐construction and self‐discovery, life goal development, identity synthesis, and internalizing problems. The findings illustrate the utility of using a self‐transformative approach to PYD in work with marginalized youth populations. 相似文献
25.
Modern patent systems are slow, inefficient, expensive, and may result in outcomes that actively harm technological progress. This paper proposes a substantive re-think of these systems and lays a foundation upon which practical solutions can be built. Many solutions proposed in the past, such as prior-art bounties, outsourced examination, and dynamic fee setting, have gone unheeded due to the cost of administering them and the rigidity of the patent system. We explore how distributed ledger technologies (DLTs) enable these major changes by altering the way stakeholders are able to interact with the patent records system. We find that transitioning to a DLT-based patent records system can enable many previously suggested improvements to current patent systems in a flexible, scalable, and transparent manner. The case for such a transition is strengthened when jointly considering the complex but common roots of problems facing modern patent systems, rather than a balkanised set of technical solutions to address each issue independently. Noting that a DLT-based system is not a panacea, we also provide comment on the political, legal, and organisational challenges that must be overcome for such changes to be implemented at scale. 相似文献
26.
Joint presentations of a conditioned stimulus (CS) and an unconditioned stimulus (US) strengthen the contingency between them, whereas presentations of one stimulus without the other degrade this contingency. For example, the CS can be presented without the US either before conditioning (CS–no US and then CS–US; latent inhibition) or after conditioning (CS–US and then CS–no US; extinction). In vertebrate subjects and several invertebrate species, a time lapse usually results in a return of the conditioned response, or spontaneous recovery. However, in land mollusks, spontaneous recovery from extinction has only recently been reported, and response recovery after latent inhibition has not been reported. In two experiments, using conditioned aversion to a food odor as a measure of learning and memory retention, we observed contingency degradation via latent inhibition (Experiment 1) and extinction (Experiment 2) in the common garden slug, Lehmannia valentiana. In both situations, the contingency degradation procedure successfully attenuated conditioned responding, and delaying testing by several days resulted in recovery of the conditioned response. This suggests that the CS–US association survived the degradation manipulation and was retained over an interval of several days. 相似文献
27.
All those who compete in the sport of rowing have used the land rowing machine, Ergometer (commonly called the ‘erg’), manufactured
by Concept II (Morrisville, Vermont, USA). Ergon is the Greek word for work, hence the Ergometer measures work. Rowers are
commonly ranked according to their ‘erg score.’ The fault in this ranking is that the land Ergometer cannot account for many
of the important technical aspects associated with rowing on the water. The goals of this project were to (1) develop a system
for on-the-water measurement of work during rowing and then (2) demonstrate the potential of such a system to quantify performance
and improve rowing technique. To achieve these goals, force was measured using strain gauges glued to the shaft of the rowing
oar and angular displacement was measured using a potentiometer. The force and displacement measurements were sent to a microcontroller,
which calculated the total work done in a particular stroke, as well as other parameters, and displayed the values to the
rower. The parameters were used to evaluate the performance of three collegiate rowers on the water. The data were also used
to plot force profiles, which were reviewed with each rower and the coach to illustrate the rowers’ habits and facilitate
improving technique. One rower was ‘tutored’ with the device through five on-the-water practices, after which his force profiles
and parameter values demonstrated significant improvement. The device not only provided a standard to which all rowers were
compared on the water, but also supplied the rowers with important information on technical aspects of their strokes and pacing
themselves. 相似文献
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Integration of microfluidic devices with pressure-driven, self-powered fluid flow propulsion methods has provided a very effective solution for on-chip, droplet blood testing applications. However, precise understanding of the physical process governing fluid dynamics in polydimethylsiloxane (PDMS)-based microfluidic devices remains unclear. Here, we propose a pressure-driven diffusion model using Fick''s law and the ideal gas law, the results of which agree well with the experimental fluid dynamics observed in our vacuum pocket-assisted, self-powered microfluidic devices. Notably, this model enables us to precisely tune the flow rate by adjusting two geometrical parameters of the vacuum pocket. By linking the self-powered fluid flow propulsion method to the sedimentation, we also show that direct plasma separation from a drop of whole blood can be achieved using only a simple construction without the need for external power sources, connectors, or a complex operational procedure. Finally, the potential of the vacuum pocket, along with a removable vacuum battery to be integrated with non-PDMS microfluidic devices to drive and control the fluid flow, is demonstrated. 相似文献