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In this article, the test particle method is used in order to calculate the Cherenkov radiation of runaway electrons. We have applied the dielectric tensor for hot magnetized plasma to derive the wave frequency of Cherenkov radiation due to particle resonance with the warm electrostatic waves. The electric field from the Cherenkov radiation is numerically calculated to model the radiation reaction force as a correction to the Coulomb logarithm in the collisional drag force. Then, the behavior of the correction term in strongly and weakly magnetized regimes is investigated. It is shown that both magnetic field strength and the speed of runaway electrons significantly modify the correction term. [ABSTRACT FROM AUTHOR]

In this paper, we theoretically investigate the transmission properties of a structure composed of a topological one-dimensional photonic crystal (1D PhC) heterostructure and a conventional 1D PhC containing indium-antimonide (InSb) as a defect layer using the transfer matrix method. The phenomenon of Fano resonance can be achieved by coupling the defect mode with the topological edge state mode, which is supported by the topological PhC. The numerical results show that a narrow Fano resonance is observed in the transmission spectrum of the structure in the presence of the external magnetic field applied to the InSb defect layer. The optical properties of the InSb defect layer, and, therefore, the Fano resonance, can be dynamically controlled by changing the applied external magnetic field. The results obtained with the proposed structure reveal that the magnetic field has the greatest influence on controlling the optical properties of the Fano resonance. These findings could be beneficial for optical devices such as optical filters, sensors, and optical switches. [ABSTRACT FROM AUTHOR]

We are examining the impact of a course-based undergraduate research experience (CURE) at a land-grant, Hispanic-serving institution in the southwestern United States. Students in our CURE completed one or two extended research projects over a single semester. Our CURE enrolled a high proportion of underrepresented minority students (70.3%), including 60.2% Hispanic students. One year after CURE completion, 31.5% of CURE students had graduated with a STEM degree, and 54.3% were enrolled in a STEM major. Pre- and post-course surveys of indicators of persistence including scientific self-efficacy, scientific identity, valuing scientific community objectives, and intention to persist showed positive shifts. Impacts on STEM persistence have implications for the role of our CURE in diversifying the STEM pipeline, particularly for students historically underrepresented in STEM.

Objective: The prevalence of bruxism in the literature has been reported differently. The aim of this study was to assess the prevalence of bruxism in patients aged 25-40 who were referred to Kerman Dental School. Methods: This analytical descriptive cross-sectional study was performed on 320 patients referred to the Department of Oral Medicine of Kerman Dentistry Faculty in the age range of 25 to 40 years old. The prevalence of bruxism as well as TMJ disorders were evaluated. Data were collected in a questionnaire and entered into SPSS version 24. Analyzing was done by a chi-square test at a significant level of 0.05. Results: The prevalence of bruxism was 23.8%, with superiority in women. Although clenching was observed in 95.5% of the patients, 84.4% showed premature contacts on teeth, most of them related to the non-working side, and 82.9% presented premature contacts on restorations, especially on the non-working side. Regarding TMD symptoms, pain was the most common (83.4%), and clicking and crepitus were seen in 42% and 6% of the patients, respectively. Also, in 63.7% of the subjects with bruxism, jaw deviation was observed, and 18.7% showed restricted jaw movement. Conclusion: The prevalence of bruxism in the studied population is in the range of similar studies. Regarding TMD, troublesome symptoms such as pain, jaw deviation, and limited mouth opening were the only ones significantly related to bruxism. [ABSTRACT FROM AUTHOR]

Background and Aims Psychological damage caused by disability is associated with personal, social, and occupational challenges of disabled people, and these people face various negative consequences. The present study aims to assess the effectiveness of the acceptance and commitment therapy (ACT) on the cognitive emotion regulation of people with physical and motor disabilities. Methods This is a quasi-experimental study with pretest/posttest design. Participants were 30 people with physical and motor disabilities (15 in the intervention group and 15 in the control group) who were selected using a purposive sampling method and random allocation. The intervention group received ACT. The data collection tool was Garnevsky's cognitive emotion regulation questionnaire (CERQ). The collected data were analyzed in SPSS software. Results The results of the analysis of covariance showed that the mean post-test CERQ scores of the intervention group were significantly lower compared to the control group, indicating the effectiveness of the ACT in improving the cognitive emotion regulation. Conclusion The ACT is effective in improving the cognitive emotion regulation of people with physical and motor disabilities. Further studies are recommended in other age, gender, and disease groups. [ABSTRACT FROM AUTHOR]

The effectiveness of computer-assisted instruction in language learning has been the topic of a long-standing debate. Prompted by this debate, we attempted to provide an updated meta-analysis on the learning effect of computer-assisted English language instruction on a broad range of study features. This meta-analysis of the experimental literature compares computer-assisted English language learning with traditional face-to-face treatments, including 140 computer-assisted learning versus classroom instruction studies, which yield 158 achievement effects. After examining the methodological quality, the overall weighted average effect size for achievement was +0.50, and it was heterogeneous. The results indicated that computer-assisted instruction had an overall medium effect on English language development. Moreover, the mixed effects model for moderator analyses indicated that Web-based instruction yielded a larger mean effect (+0.54) than traditional computer-assisted instruction (+0.47). Further analyses led to the identification of four important moderators of English language learning: type of interaction, communication mode, language learning context, and treatment duration. Insights into the evolution, not only in the technological but also in the sociological context and educational theories, and the future prospects of computer-assisted instruction are discussed.

Current trends in the field of educational technology indicate a shift in pedagogical assumptions and theoretical frameworks that favor active involvement of self-directed learners in a constructivist environment. This study probes the influence of electronic portfolio evaluation on vocabulary learning of Iranian university students and the possible implications this influence affords. For this aim, the study recruited 66 students who were randomly assigned to the e-portfolio group and the traditional assessment group. The experimental group kept an e-portfolio in the intermediate level English language course while the traditional assessment group did not. The results revealed that the e-portfolio group outperformed the traditional assessment group in terms of vocabulary learning on the posttest. The results also showed that e-portfolio boosted students' motivation for learning new items. The perceptions of the participants in the e-portfolio group reflected that they benefited from the integration of technology and various educational activities and enjoyed keeping an e-portfolio. Finally, initial guidelines about how to use the instrument as part of the curriculum are discussed.

Severe forms of dental fluorosis is commonly reported in Kuhbanan, Iran. The extensive discoloration can be justified to a large extent by the high fluoride levels in drinking and agricultural water of the region. However its high intensity brings other factors to mind, such as the level of fluoride in the breathing air of inhabitants. Therefore, the aim of the present study was to assess fluoride levels in the air of Kuhbanan region. Twelve air samples were obtained from different areas of Kuhbanan region (center of the city and village of Jevar) and city of Kerman. The NIOSH7902 method was used to determine the concentration of air fluoride in the target areas. Fluoride levels of each sample were obtained with the two following methods to increase the accuracy; 1-Fluoride Ion-Selective Electrode system and 2-additive system of Zirconium-Cyanine reagent and spectrophotometer. Finally data were analysed using SPSS software version 26 and the statistical test: Mann-Whitney test. Significance level was set at 0.05. Fluoride levels in the air of Kuhbanan and the village of Jevar was significantly higher than the city of Kerman. Mean±SD of fluoride level in the air in Kuhbanan city and Jevar village was 0.520±0.033 and 0.905±0.104 mg/m³, respectively. In contrast, in the air of Kerman city it was 0.141±0.041 mg/m³. The differences are statistically significant (P<0.05). Fluoride levels in the air of Kuhbanan and the village of Jevar is more than the city of Kerman. Many coal mines exist close to Kuhbanan and the village of Jevar and high levels of fluoride are emitted into the air. It is suggested that the fluoride level in the soil of this region also be determined. The findings of this study are important for the inhabitants and policy makers. [ABSTRACT FROM AUTHOR]

Statement of the Problem: Camelia Sinenis or green tea (GT) and Teucrium polium (TP) are known to have a great antimicrobial potential on salivary Streptococcus mutans (S. mutans).Their efficacy should be examined compared to the gold standard antimicrobial agents. Purpose: To evaluate the effects of Camelia Sinenis or green tea (GT) and Teucrium polium (TP) extracts in comparison with chlorhexidine gluconate (CHG) on salivary S. mutans levels. Materials and Method: This double-blinded randomized clinical trial study was conducted on 90 preschool children aged 4 to 6 years and assigned randomly (simple randomization) to three groups as GT, TP, and CHG. Unstimulated saliva samples were then collected in three times as before application of agents, after half an hour, and after one week. To determine S. mutans levels, quantitative polymerase chain reaction (qPCR) technique was additionally utilized. Statistical analysis was also fulfilled using Shapiro-Wilk test, Friedman test, Chisquare test, paired sample t-test, repeated measures analysis of variance (ANOVA), and Mann-Whitney U test at a significance level of 0.05. Results: The results of this study established a significant difference between mean salivary S. mutans levels after administration of the three compounds. Although the mean of S. mutans levels reduced significantly following the application of CHG and TP after half an hour, the mean salivary S. mutans levels in the group receiving GT declined in a significant manner only one week later (p< 0.05). Conclusion: The results of this study indicated that GT and TP extracts had considerable effects on salivary S. mutans levels compared with CHG. [ABSTRACT FROM AUTHOR]