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21.
This study investigated the effect of Pen-Point and Powerbook computers on solving a multiple step chemistry (molaritý) problem among White, Afro-American and Hispanic students (N=60) at the high school level. The screens on both computers were partitioned into a work field and a reasoning field. Both computers were programmed to record the time spent in each field, the number of entries made, and a copy of the entries made. Statistical analysis of data showed that more of the White and Afro-American Pen-Point computer users solved the problem correctly than did students using the Powerbook computer. All three ethnic groups made fewer entries, and took less time using the Pen-Point computer than the Powerbook. Attitude survey results of all ethnic groups showed that more Pen-Point computer users felt comfortable working with computers. Over all, the results suggest that the Pen-Point computer has a more positive effect on the problem solving performance and attitude of students towards computers than the Powerbook computer.  相似文献   
22.
Addressing the need for suicide prevention on campus, I CARE training, developed and facilitated by counseling center clinicians, trains students, staff, and faculty to provide support to students experiencing distress or mental health problems. We assessed its impact using a mixed-methods approach. Quantitative analyses demonstrated significant increases in knowledge of intervention skills and readiness to intervene from pretraining to posttraining. Knowledge and readiness remained significantly higher than preworkshop for the entire follow-up evaluation period, extending 15 months posttraining. Qualitative analyses revealed the value of experiential activities and emotional processing in increasing participants’ comfort and preparedness to intervene in challenging situations.  相似文献   
23.
In this study, a simple roller burnishing tool was made to operate burnishing processes on A356/5%SIC metal matrix composite fabricated by electromagnetic stir casting under different parameters. The effects of burnishing speed, burnishing force and number of burnishing passes on the surface roughness and tribological properties were measured. Scanning electron microscopy (SEM) graphs of the machined surface with PCD (insert-10) tool and roller burnished surface with tungsten carbide (WC) roller were taken into consider- ation to observe the surface finish of metal matrix composites. The mechanical properties (tensile strength, hardness, duc- tility) of A356/5%SIC metal matrix composites were studied for both unburnished samples and burnished samples. The results revealed that the roller burnished samples of A356/ 5%SIC led to the improvement in tensile strength, hardness and ductility. In order to find out the effects of roller bur- nishing process parameters on the surface roughness of A356/ 5%SIC metal matrix composite, response surface methodol- ogy (RSM) (Box-Behnken design) was used and a prediction model was developed relevant to average surface roughness using experimental data. In the range of process parameters, the result shows that roller burnishing speed increases, and surface roughness decreases, but on the other hand roller burnishing force and number of passes increase, and surface roughness increases. Optimum values of burnishing speed (1.5 m/s), burnishing force (50 N) and number of passes (2) during roller burnishing of A356/5%SIC metal matrix com- posite to minimize the surface roughness (predicted 1.232 μm) have been found out. There was only 5.03% error in the experimental and modeled results of surface roughness.  相似文献   
24.
Quantitative trait loci (QTL) analysis was conducted in bread wheat for 14 important traits utilizing data from four different mapping populations involving different approaches of QTL analysis. Analysis for grain protein content (GPC) sug- gested that the major part of genetic variation for this trait is due to environmental interactions. In contrast, pre-harvest sprouting tolerance (PHST) was controlled mainly by main effect QTL (M-QTL) with very little genetic variation due to environmental interactions; a major QTL for PHST was detected on chromosome arm 3AL. For grain weight, one QTL each was detected on chromosome arms 1AS, 2BS and 7AS. QTL for 4 growth related traits taken together detected by different methods ranged from 37 to 40; nine QTL that were detected by single-locus as well as two-locus analyses were all M-QTL. Similarly, single-locus and two-locus QTL analyses for seven yield and yield contributing traits in two populations respectively allowed detection of 25 and 50 QTL by composite interval mapping (CIM), 16 and 25 QTL by multiple-trait composite interval mapping (MCIM) and 38 and 37 QTL by two-locus analyses. These studies should prove useful in QTL cloning and wheat improvement through marker aided selection.  相似文献   
25.
Protein fraction termed P2 was obtained from sonicates of Mycobacterium smegmatis, subjected to ammonium sulphate precipitation. P2 fraction was further fractionated into 4 fractions (PeakI-IV) by DEAE cellulose ion-exchange chromatography. ELISA was performed on the sera of 104 tuberculous cases and 62 controls, using P2 fractions Peak I as test antigens. Though the mean ELISA values in tuberculous cases were higher than the controls, no statistically significant difference was found between the two. Antigens P2, Peak I and IV were tested on Western blots with pooled sera from tuberculous cases as well as controls. P2 fraction, Peak-I and IV were separated on PAGE-SDS, electroblotted onto nitrocellulose Sheets and the blots were subjected to ELISA. Peak IV appeared as a single band (M.W. 55,000). P2 fraction exhibited some discriminatory bands on development of blots.  相似文献   
26.
Methionine synthase reductase (MTRR) is an important enzyme of the folate/homocysteine pathway. It is responsible for regulation of methionine enzyme by reductive methylation. A common variant A66G is reported in the FMN-binding domain of the MTRR gene, which leads to substitution of isoleucine by methionine (I22M) in MTRR enzyme with reduced activity. Reduced catalytic activity of enzyme leads to high homocysteine concentration in blood and increases risk for numerous diseases. The frequency of A66G polymorphism varies in different ethnic groups. The present study has been designed to evaluate the frequency of MTRR A66G gene polymorphism in the Eastern UP population by PCR–RFLP method. Along with this we also performed a meta-analysis to evaluate the global prevalence of this polymorphism. Databases were screened to identified the eligible studies. The prevalence of the G allele and GG genotype was determined by the use of prevalence proportion with 95% CI. Open meta-analyst software was used for the meta-analysis. Total 1000 blood samples were analyzed, the frequencies of A and G alleles were 0.35 and 0.65 respectively. Meta-analysis results revealed that the prevalence of G allele and GG genotype were 49.4% (95% CI 40.6–58.1, p ≤ 0.001) and 24.3% (95% CI 17.8–30.9, p ≤ 0.001) respectively. In sub-group meta-analysis, the lowest frequency of G allele was found in South America (32.7%; 95% CI 14.1–51.3, p ≤ 0.001), and highest in Asia (56.4%; 95% CI 39.5–73.3, p ≤ 0.001). The results of the meta-analysis showed that the Asian population has the highest frequency of G allele and highest frequency of the GG genotype was found in the European population.  相似文献   
27.
This pilot study set out to examine the impact of a regular practice of yoga within schooling curricular hours on the well-being and behaviors of atypically developing children. The design of this study was based on a qualitative hermeneutic-phenomenology approach. The intervention consisted of 5 weekly sessions of yoga of 15 minutes each and composed of breathing techniques (pranayama), postures (pranayama), and lying down relaxation exercises (yoga nidra). The research site was a special needs school in South Auckland, New Zealand in an area characterized by poor socio-economic living conditions with a composite range of different ethnic groups. The findings of this study suggest that a regular practice of yoga can have numerous benefits for children on the Autism Spectrum Disorder (ASD). They found yoga to be a fun-filled and engaging experience. They improved significantly in their flexibility levels and general physical health. Emotionally, the children reported that the breathing techniques allowed them to feel calmer and more relaxed. The children felt that incorporating a regular practice of yoga within formal curriculum will be another effective tool to enhancing their overall health and well-being.  相似文献   
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29.
The University of Florida offers an online professional practice Ed.D. focused on Educational Technology. Twenty-three students have completed professional practice dissertations and graduated since the program’s inception in 2008. The purpose of this article is to share what these dissertations have looked like and to begin a dialogue about professional practice dissertations completed in online educational technology programs. Specifically, we (1) provide an overview of different ways professional practice Ed.D. dissertations are structured, (2) share guiding principles for professional practice dissertations in our Ed.D. program, (3) analyze the ways in which these guiding principles played out in the dissertations and (4) discuss the implications of our analysis for our program and for other online professional practice programs in Educational Technology.  相似文献   
30.
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