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121.
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   
122.
This work deals with an environmental problem related to controlling eutrophication inside a sensitive zone, by means of a regulation of the wastewater discharges in the region. After setting a detailed mathematical formulation of the optimal control problem posed on a free-boundary moving domain, we present several theoretical results on existence-regularity of optimal solutions, and their characterization by a first order optimality system. In the second part of the work a complete numerical algorithm for the resolution of the control problem is proposed, and several numerical examples are also given.  相似文献   
123.
Microfluidic devices allow for the production of physiologically relevant cellular microenvironments by including biomimetic hydrogels and generating controlled chemical gradients. During transport, the biomolecules interact in distinct ways with the fibrillar networks: as purely diffusive factors in the soluble fluid or bound to the matrix proteins. These two main mechanisms may regulate distinct cell responses in order to guide their directional migration: caused by the substrate-bound chemoattractant gradient (haptotaxis) or by the gradient established within the soluble fluid (chemotaxis). In this work 3D diffusion experiments, in combination with ELISA assays, are performed using microfluidic platforms in order to quantify the distribution of PDGF-BB and TGF-β1 across collagen and fibrin gels. Furthermore, to gain a deeper understanding of the fundamental processes, the experiments are reproduced by computer simulations based on a reaction-diffusion transport model. This model yields an accurate prediction of the experimental results, confirming that diffusion and binding phenomena are established within the microdevice.  相似文献   
124.
Summary Recognizing and validating the existence of computer anxiety in the training process is the first step toward helping adult learners to overcome this barrier. By taking steps to ensure that the environment is conducive to learning, trainers will effectively traverse the first hurdle in an often tedious process-developing trust and encouraging exploration among the computerphobic.  相似文献   
125.

Objectives

During intrafamilial conflicts children are often innocent bystanders, caught in the crossfire. In such situations, they are at increased risk to become directly involved in abusive verbal behavior of the perpetrator, and exposed to being shouted or yelled at, threatened, rejected and even physically abused. The present study has two main objectives: (1) ascertain a national base rate of intrafamilial conflicts and physical violence at home among Icelandic adolescents; and (2) to investigate the association of witnessing and/or having been a part of intrafamilial conflict or physical violence at home with variables that relate to mental health and well-being.

Methods

The participants were 3,515 students, 14- and 15-year-old, in the national compulsory school system in Iceland. As a part of the 2003 ESPAD survey, each pupil was asked about experiences of severe verbal arguments and physical violence at home as well as their background, behaviors, and mental health assessed with the use of tested measurement scales such as the Symptom Distress Checklist 90 (SCL-90) and the Rosenberg Self-Esteem Scale.

Results

About 22% of the participants stated that they had witnessed a severe verbal argument between parents and 34% stated that they had been involved in a severe verbal argument with parents. This rate was slightly higher for girls compared to boys. All together 7% of adolescents had witnessed physical violence at home where an adult was involved and 6% of the participants stated that they had experiences of being involved in physical violence at home where an adult was involved. Witnessing or being involved in severe verbal arguments at home and/or witnessing or being involved in physical violence with an adult was significantly associated with greater levels of depression, anger, and anxiety, and negatively related with self-esteem (p < 0.01).

Conclusions

Many adolescents in Iceland witness severe parental verbal arguments or physical violence between adults in their homes and some are directly involved in such acts. It affects their long-term emotional and behavioral development and well-being.

Practice implications

Preventive measures have to be implemented at an early age and should include, but not be limited to, information on disciplining and upbringing of children and the negative impact of intrafamilial conflicts on the long-term health of their children. Due attention should be given to the health and well-being of children where such violence is known to occur.  相似文献   
126.
We describe the results of electromigration desalination of two soluble salt-contaminated Galician granites. The efficacy of electromigration, which had not been previously applied to granite, was assessed for two types of granite contaminated with a 20% NaCl solution and seawater. Desalination effectiveness was evaluated as follows: (1) analysis of anode and cathode ion content during testing; (2) analysis of ions at different distances from the electrodes after testing; (3) pH assessment of the stone surfaces; and (4) evaluation of colour changes. Results were very satisfactory; by the end of testing, chloride was reduced by almost 100% in both the NaCl and seawater contaminated samples. Sulfate reduction was also significant, despite this ion's lower mobility. The granite pH values remained close to neutral and colour changes were minimal. The difference in effectiveness of the process for the two types of stone was associated with their dissimilar pore structure.  相似文献   
127.
Research in Science Education - The research compares teachers’ and their pupils’ performance on plant nutrition. The misconceptions of 89 primary school children from one state school...  相似文献   
128.
Science & Education - Science and mathematics are universal endeavors. However, the historical perspective of science and mathematics has been westernized across the curriculum in the USA....  相似文献   
129.
One of the most widely used solutions to fix and preserve organic tissues is formaldehyde, despite reservations regarding its toxicity and the fact that formaldehyde-embalmed bodies lose their original characteristics. Anatomy laboratories have been replacing formaldehyde with solutions that retain the characteristics of fresh tissue. For this purpose, alternative solutions with a very low concentration of formaldehyde or without any formaldehyde have been analyzed. The objective of this study was to compare biometry, coloration, haptic properties, and bacterial load on animal specimens (pig kidneys) embalmed with formaldehyde, and with Chilean Conservative Fixative Solution with and without formaldehyde (formaldehyde chCFS and formaldehyde-free chCFS). Also, the perception of health and biological science students toward specimens treated with different solutions was assessed. The results indicated that there were no significant differences in specimens’ retraction, or bacterial load. Students showed a preference for organs embalmed in formaldehyde chCFS and formaldehyde-free chCFS; indicating that with these treatments they could better visualize structures and that the prosections had greater flexibility and the colors were more similar to those of fresh tissue. Additionally, students recommended the material embalmed in formaldehyde chCFS and formaldehyde-free chCFS for anatomy learning. In contrast, students indicated that formaldehyde-fixation negatively affected their practical experience. In conclusion, embalming with formaldehyde chCFS or formaldehyde-free chCFS provides an advantageous practical experience over the use of formaldehyde and may be an alternative to replace the use of formaldehyde in anatomy laboratories.  相似文献   
130.
SYNOPSIS

Objective . To explore whether maternal sensitivity is associated with Autism Spectrum Disorder (ASD) severity in children with and without ASD. Design . The samples consisted of 25 Mexican dyads of children with ASD (aged 3.1-6.9 years) and their mothers (aged 20-47 years) and 24 Mexican dyads of children without ASD (aged 3.4-6.7 years) and their mothers (aged 24-45 years). Maternal sensitivity and ASD severity symptoms were scored from 2-h videos of mother-child daily interactions. Results . A between-group comparison showed a trend toward less severe ASD in children with highly sensitive mothers, specifically in the Nonverbal Communication subdomain. Conclusions . Greater maternal sensitivity is associated with improved social ability in children with ASD.  相似文献   
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