排序方式: 共有36条查询结果,搜索用时 22 毫秒
21.
Ikram Khan Anil Prabhakar Chloe Delepine Hayley Tsang Vincent Pham Mriganka Sur 《Biomicrofluidics》2021,15(2)
Organoids are biological systems grown in vitro and are observed to self-organize into 3D cellular tissues of specific organs. Brain organoids have emerged as valuable models for the study of human brain development in health and disease. Researchers are now in need of improved culturing and imaging tools to capture the in vitro dynamics of development processes in the brain. Here, we describe the design of a microfluidic chip and bioreactor, to enable in situ tracking and imaging of brain organoids on-chip. The low-cost 3D printed microfluidic bioreactor supports organoid growth and provides an optimal imaging chamber for live-organoid imaging, with drug delivery support. This fully isolated design of a live-cell imaging and culturing platform enables long-term live-imaging of the intact live brain organoids as it grows. We can thus analyze their self-organization in a controlled environment with high temporal and spatial resolution. 相似文献
22.
Chloe Patton 《Assessment & Evaluation in Higher Education》2012,37(6):719-731
This paper explores the attitudes and perceptions of three cohorts of Australian humanities and social science undergraduate students towards peer assessment. It seeks to gain a deeper understanding of local dissatisfaction with peer assessment through an in‐depth analysis of students’ contributions to focus group discussions. Responding to education theorists’ claims that peer and other forms of innovative assessment empower students, the paper concentrates on themes of power evident within students’ narratives. The interpretive framework coheres around four interrelated conceptions of power: sovereign, epistemological, disciplinary and structural. Students were found to support the notion of peer assessment as a formative exercise, yet were highly critical of it as a summative practice. Significantly, some of the students’ dissatisfaction stemmed from broader changes across the higher education sector more generally. The paper draws attention to the need for this to be taken into account when considering assessment as a technology of power and empowerment. 相似文献
23.
This study employs data from both kindergarten cohorts of the Early Childhood Longitudinal Study (n ~ 12,450 in 1998; n ~ 11,000 in 2010) to assess whether associations between preschool participation and children's academic and behavioral outcomes—both at school entry (Mage = 5.6 years in both cohorts) and through third grade—have changed over time. Findings are strikingly similar across these two, nationally representative, U.S. cohorts: preschool is positively associated with academic outcomes and negatively associated with behavioral outcomes both at school entry and as children progress through school. Heterogeneity is documented with respect to child and preschool characteristics. However, there is no evidence that associations between preschool and medium-term child outcomes differ by elementary school characteristics. 相似文献
24.
Although the characteristic morphology of rugby forwards playing different positions in the rugby scrum has been well documented, a complete picture of the force characteristics that different players produce has not been evaluated. This is especially true for the movement of the centre of pressure (CoP) elicited during scrummaging in a forward direction. An individual scrummaging ergometer was therefore developed to measure the CoP of an individual scrum action using conventional torque calculations. Calibration of the measurement system revealed measured force errors within 16.6 N of the actual force and errors of less than 3.96 mm for CoP location determination. Thirty-nine club level rugby union players (22 front rows, 11 locks and six back rows) scrummed against the ergometer on an outdoor rugby field. Differences between the three groups were tested using one-way ANOVAs. The maximum force for different players was 2253.6 ± 649.0 N over the entire subject group. There were no differences in the individual compressive force between the groups [front rows: 2404.0 ± 650.3 N; locks: 2185.6 ± 568.9 N; back rows: 1826.9 ± 670.2 N (p = 0.143)]. Individually, front rows started at a higher position than back rows (p = 0.009) and were at a higher vertical position than locks when producing maximum force (p = 0.028). Front rows had lower variation in the CoP (p = 0.044) and less movement to achieve their maximum force (p = 0.020) than locks. Front rows moved less overall than back rows (p = 0.028) during the scrum trial. The design and application of the individual scrum ergometer showed with good limits of agreement that differences in force magnitude and CoP exist within scrummaging players. Practically, the application of this ergometer may assist in the individual optimisation of scrummaging performance. 相似文献
25.
Amy M. Kolak Tara J. Frey Chloe A. Brown Lynne Vernon-Feagans 《Early education and development》2013,24(8):1232-1244
Research Findings: Minor illnesses, such as upper respiratory infections, stomachaches, and fevers, have been associated with children's decreased activity and increased irritability. This multi-method investigation of 110 day care–attending children examined whether experience with recurrent, minor illnesses and negative emotionality worked together to predict young children's social functioning. Minor illness experience was assessed via weekly health screenings conducted by nurses. Toddlers' negative emotionality and social behavior were assessed using mothers' and fathers' reports. The two dimensions of negative emotionality and minor illness experience operated in different ways to predict children's functioning. Toddlers rated as more temperamentally angry displayed less social competence, especially when they also experienced high proportions of minor illness. Temperamentally fearful children exhibited more externalizing problems when they experienced a higher frequency of illness, whereas fearfulness was not associated with externalizing problems for children who were not frequently ill. Practice or Policy: Children's frequent experience with minor illnesses combined with negative emotionality appears to place toddlers at a heightened risk for exhibiting behavior problems. These findings have implications for child and family well-being as well as interactions with child care providers and peers within child care settings. Interventions could be developed to target “at risk” children. 相似文献
26.
27.
28.
29.
Michael J. Duncan Alexandra P. Dobell Chloe L. Caygill Emma Eyre Jason Tallis 《European Journal of Sport Science》2019,19(1):103-111
AbstractThe current study examined the effect of acute caffeine ingestion on mean and peak power production during upper body Wingate test (WANT) performance, rating of perceived exertion, readiness to invest effort and cognitive performance. Using a double-blind design, 12 males undertook upper body WANTs, following ingestion of caffeine (5?mg*kg?1) or placebo. Pre-substance ingestion, 60?mins post substance ingestion and post exercise participants completed measures of readiness to invest physical and mental effort and cognitive performance. Peak power was significantly higher (P?=?.026), fatigue index greater (P?=?.02) and rating of perceived exertion lower (P?=?.025) in the presence of caffeine. Readiness to invest physical effort was also higher (P?=?.016) in the caffeine condition irrespective of time point (pre, 60?mins post ingestion and post exercise). Response accuracy for incongruent trials on the Flanker task was superior in the presence of caffeine (P?=?.006). There was a significant substance?×?time interaction for response speed in both congruent and incongruent conditions (both P?=?.001) whereby response speeds were faster at 60?mins post ingestion and post exercise in the caffeine condition, compared to placebo. This is the first study to examine the effects of caffeine ingestion on this modality of exercise and suggests that caffeine ingestion significantly enhances peak power, readiness to invest physical effort, and cognitive performance during WANT performance. 相似文献
30.
Rachael W. Cheung Chloe Austerberry Pasco Fearon Marianna E. Hayiou-Thomas Leslie D. Leve Daniel S. Shaw Jody M. Ganiban Misaki N. Natsuaki Jenae M. Neiderhieser David Reiss 《Child development》2024,95(3):699-720
Parenting and children's temperament are important influences on language development. However, temperament may reflect prior parenting, and parenting effects may reflect genes common to parents and children. In 561 U.S. adoptees (57% male) and their birth and rearing parents (70% and 92% White, 13% and 4% African American, and 7% and 2% Latinx, respectively), this study demonstrated how genetic propensity for temperament affects language development, and how this relates to parenting. Genetic propensity for negative emotionality inversely predicted language at 27 months (β = −.15) and evoked greater maternal warmth (β = .12), whereas propensity for surgency positively predicted language at 4.5 years (β = .20), especially when warmth was low. Parental warmth (β = .15) and sensitivity (β = .19) further contributed to language development, controlling for common gene effects. 相似文献