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881.
Kimberly R. Osborne Ashley A. Walsdorf Mia A. Smith-Bynum Samantha Redig Dawn Brinkley Margaret Tresch Owen Margaret O’Brien Caughy 《Child development》2023,94(1):219-236
Guided by the Theory of Racial Socialization in Action (TRSA; Smith-Bynum in press), this study examined observed caregiver-provided ethnic-racial socialization in response to a school-based discriminatory dilemma. Forty-five Black and 36 Latinx caregivers (88% mothers) with low-income and their children (Mage = 11.09, SD = 0.29; 46.3% female) participated in Dallas, Texas from 2018 to 2019. Dyads responded to a hypothetical scenario in which a school counselor makes a discriminatory comment to the child. Results of a factor mixture analysis suggested that caregivers engaged in the dialogue using one of four approaches: Low-engaged, Legacy, Racial Literacy, or High-engaged. Profiles were found to differ significantly by the race/ethnicity and language of caregivers and were associated with youth’s concurrent behavioral engagement (R2 = .04). 相似文献
882.
Sarah S. Mire Milena A. Keller-Margulis Amy K. Izuno-Garcia Emily R. Jellinek Elías S. Loría Garro 《Psychology in the schools》2023,60(2):345-363
Students with autism may struggle to develop the academic skills necessary for success in school and beyond. Understanding and improving academic skills performance requires appropriate measurement approaches. One such option that has been minimally studied with students with autism is curriculum-based measurement (CBM). Coinciding with the need to study different approaches to academic skills measurement for students with autism was the global pandemic which forced a shift to remote service delivery with little warning. While some autistic students struggled with this shift, others thrived, raising questions about how to further support students with autism in virtual formats. The purpose of this study was to examine the feasibility of using remotely administered CBM for autistic students by studying both the practicality and acceptability of this approach. Five students with autism (Grades 2–5) participated in this pilot study, completing reading, math, and writing CBMs at three time points. Student behavior and assessor fidelity were collected to examine practicality; assessor ratings of usability provided insight regarding the acceptability of the approach. Results indicated that remotely administered CBM is feasible for some students with autism: all participants completed the study tasks with minimal behavioral difficulties, and assessor ratings of acceptability were high. 相似文献
883.
Maria E. Hernández Finch Beth Trammell Asia R. Hulse William H. Finch Aimee Wildrick Elizabeth F. Floyd Jenna Pittenger David E. McIntosh 《Psychology in the schools》2023,60(2):282-294
Understanding the relationship between executive functioning and its connection to working memory and adaptive functioning can inform planning and employment efforts. This study explored the relationship between memory and adaptive functioning with a sample of Autistic youths/young adults. Participant mean age was 21.3 (SD = 3.0). Of the 22 participants, 17 were male, and 19 white, non-Hispanic/Latina/o/x. All but one lived with their parent(s). Participants were administered a full battery assessing cognitive ability (WAIS-IV), memory and executive functioning (WMS-IV and DKEFS), autism symptomatology (ADOS-II), and adaptive functioning (SIB-R). A multivariate lasso regression model was used. Memory, especially as measured on the WMS-IV, was found to be significantly related to adaptive functioning and autism symptomatology. There appears to be continuing evidence that memory is highly related to adaptive functioning and autism symptomatology. Interventions involving auditory and immediate memory could be helpful in promoting more mutually effective social interactions necessary for positive employment outcomes. 相似文献
884.
The purpose of this article is to explore the intersectionality of autism and sociocultural factors as well as discuss the complexities associated with appropriate assessment, diagnosis, and intervention. Based on a review of the literature, the authors present a brief history of the emergence of the term autism and highlight factors that have contributed to current concerns about failures to appropriately recognize autism within diverse populations. Referencing extant research as well as professional practice standards, this article examines aspects of autism and intersectionality, and explores some of the associated challenges related to assessment, diagnosis, and intervention. Further, the authors reflect on the critical importance of carefully considering all aspects of a child's identity when engaging in autism assessment and intervention within the school setting. School-based practitioners are provided with guidance for addressing the needs of diverse populations of students with autism. 相似文献
885.
Rayendra Wahyu Bachtiar Ralph F. G. Meulenbroeks Wouter R. van Joolingen 《科学教学研究杂志》2024,61(2):289-318
Previous studies have documented the promising results from student-constructed representations, including stop-motion animation (SMA), in supporting mechanistic reasoning (MR), which is considered an essential thinking skill in science education. Our current study presents theoretically and empirically how student-constructed SMA contributes to promoting MR. As a theoretical perspective, we propose a framework hypothesizing the link between elements of MR and the construction nature of SMA, that is, chunking and sequencing. We then examined the extent to which this framework was consistent with a multiple-case study in the domain of static electricity involving five secondary school students constructing and using their own SMA creation for reasoning. In addition, students' reasoning in pre- and postconstruction of an SMA was examined. Our empirical findings confirmed our framework by showing that all students identified the basic elements of MR, that is, entities and activities of entities, when engaging in chunking and sequencing. Chunking played a role in facilitating students to identify entities responsible for electrostatic phenomena, and sequencing seemed to elicit students to specify activities of these entities. The analysis of students' reasoning in pre- and postconstruction of SMA found that student-generated SMA has a potential effect on students' retention of the use of MR. Implications for instruction with SMA construction to support MR are discussed. 相似文献
886.
Regi Jose G. R. Sajitha K. T. Augusti 《Indian journal of clinical biochemistry : IJCB》2014,29(2):119-132
Nutraceuticals are nutritional medicines which are present in edible food items. Most of them are antioxidants with various other biological properties viz, anti inflammatory, anti atherogenic, anticancer, anti viral, anti aging properties etc. They are as simple as minerals like Se2+ to complex organic molecules such as glycyrrhizin (Ca2+, K+ salts of glycyrrhizic acid). They can prevent as well as cure various diseases. Most of the medical people are not aware of the importance of the nutraceuticals as such matters are not part of their text books. Many still think that vitamins are the major nutritional medicines. Actually other dietary principles like terpenes, carotenes, phytosterols, polyphenols, flavanoids, di and poly sulphides, their sulfoxides and their precursor amino acids are necessary to scavenge free radicals in the body which are reactive oxygen species to protect and maintain the vitamin levels in the body. They down regulate the activities of those enzymes which are increased in diseases and they increase those that remove oxidants and detoxify carcinogens. They are immune boosters too. Recently glucosinolates, non toxic alkaloids, certain proteins and even fiber are included in the list of nutraceuticals. 相似文献
887.
In the present article Parameterized Perturbation Method (PPM) is used to obtain the solutions of momentum and heat transfer equations of non-Newtonian fluid flow in an axisymmetric channel with porous wall for turbine cooling applications. The validity of the results of PPM solution were verified by comparison with numerical results obtained using a fourth order Runge–Kutta method. These comparisons reveal that Parameterized Perturbation Method is a powerful approach for solving this problem. The analytical investigation is carried out for different governing parameters namely, Reynolds number, injection Reynolds number, Prandtl number and power law index. The results show that skin friction coefficient increases with increase of Reynolds number, especially at high Reynolds numbers. Also it can be found that Nusselt number has direct relationship with Reynolds number, Prandtl number and power law index. 相似文献
888.
This paper deals with the problem of adaptive output feedback neural network controller design for a SISO non-affine nonlinear system. Since in practice all system states are not available in output measurement, an observer is designed to estimate these states. In comparison with the existing approaches, the current method does not require any information about the sign of control gain. In order to handle the unknown sign of the control direction, the Nussbaum-type function is utilized. In order to approximate the unknown nonlinear function, neural network is firstly exploited, and then to compensate the approximation error and external disturbance a robustifying term is employed. The proposed controller is designed based on strict-positive-real (SPR) Lyapunov stability theory to ensure the asymptotic stability of the closed-loop system. Finally, two simulation studies are presented to demonstrate the effectiveness of the developed scheme. 相似文献
889.
Arnold Chen Royal Wang Candace R. S. Bever Siyuan Xing Bruce D. Hammock Tingrui Pan 《Biomicrofluidics》2014,8(6)
The emerging technologies on mobile-based diagnosis and bioanalytical detection have enabled powerful laboratory assays such as enzyme-linked immunosorbent assay (ELISA) to be conducted in field-use lab-on-a-chip devices. In this paper, we present a low-cost universal serial bus (USB)-interfaced mobile platform to perform microfluidic ELISA operations in detecting the presence and concentrations of BDE-47 (2,2′,4,4′-tetrabromodiphenyl ether), an environmental contaminant found in our food supply with adverse health impact. Our point-of-care diagnostic device utilizes flexible interdigitated carbon black electrodes to convert electric current into a microfluidic pump via gas bubble expansion during electrolytic reaction. The micropump receives power from a mobile phone and transports BDE-47 analytes through the microfluidic device conducting competitive ELISA. Using variable domain of heavy chain antibodies (commonly referred to as single domain antibodies or Nanobodies), the proposed device is sensitive for a BDE-47 concentration range of 10−3–104 μg/l, with a comparable performance to that uses a standard competitive ELISA protocol. It is anticipated that the potential impact in mobile detection of health and environmental contaminants will prove beneficial to our community and low-resource environments. 相似文献
890.
Droplet-based microfluidics has gained extensive research interest as it overcomes several challenges confronted by conventional single-phase microfluidics. The mixing performance inside droplets/slugs is critical in many applications such as advanced material syntheses and in situ kinetic measurements. In order to understand the effects of operating conditions on the mixing performance inside liquid slugs generated by a microfluidic T-junction, we have adopted the volume of fluid method coupled with the species transport model to study and quantify the mixing efficiencies inside slugs. Our simulation results demonstrate that an efficient mixing process is achieved by the intimate collaboration of the twirling effect and the recirculating flow. Only if the reagents are distributed transversely by the twirling effect, the recirculating flow can bring in convection mechanism thus facilitating mixing. By comparing the mixing performance inside slugs at various operating conditions, we find that slug size plays the key role in influencing the mixing performance as it determines the amount of fluid to be distributed by the twirling effect. For the cases where short slugs are generated, the mixing process is governed by the fast convection mechanism because the twirling effect can distribute the fluid to the flow path of the recirculating flow effectively. For cases with long slugs, the mixing process is dominated by the slow diffusion mechanism since the twirling effect is insufficient to distribute the large amount of fluid. In addition, our results show that increasing the operating velocity has limited effects on improving the mixing performance. This study provides the insight of the mixing process and may benefit the design and operations of droplet-based microfluidics. 相似文献