The Monster is Growing

Panel: America Abroa

Analysis of different class sizes on decision making processes and teaching behaviors of highly experienced teachers (HETs) and less experienced teachers (LETs)

Objectives. This study examined the decision making process employed by two highly experienced teachers (HETs) and two less experienced teachers (LETS) as they planned for and taught lessons with two different class sizes; n=15-16 and n=30-31. A secondary purpose of this study was to investigate the influence of class size on teaching behaviors and student learning. Finally, this study used in-depth interviews to describe concerns associated with teaching and preparing lessons for classes of different size.;Design and setting. This was a mixed-methods study that utilized both behavioral analysis and qualitative methods of investigation. Qualitative methods included think-aloud, stimulated-recall techniques and semi-structured, open-ended interviews which were used to describe participants teaching concerns when dealing with class size. Quantitative methods included the use of the West Virginia University Teaching Evaluation System (WVUTES; Hawkins & Wiegand, 1989), and Field System Analysis (FSA; Sharpe & Hawkins, 1992) which were used to examine the influence of class size on teaching and student learning behaviors.;Subjects. Two highly experienced physical education teachers (HET1 and HET2) and two less experienced physical education teachers (LET1 and LET2, student teachers) were involved in this study. Pseudonyms were used for all participants in this study including: Erick Sam (HET1), Erin Hong (HET2), Nancy Young (LET1) and Nathan Smith (LET2). A total of 184 student participants were recruited from the two different elementary schools along with their cooperating physical education teachers.;Results. WVUTES data showed that HETs used similar instructional behaviors in terms of the amount, duration and frequency of feedback given during both classes. FSA revealed that all teachers provided individual feedback more often in smaller classes. Experienced teachers provided more individual feedback in larger classes, whereas their less experienced counterparts provided individual feedback more frequently only in smaller classes.;Conclusions. Smaller classes are more beneficial especially for less experienced teachers, due to the increase in frequency of individual feedback. Class size was an important consideration for planning, specifically selecting content and the organizational structure. Experienced teachers used multiple formations to deal with variations in class size. Less experienced teachers tend to use the one teaching format (either station or cohort) they were most comfortable with for both classes regardless of size. In this study, station teaching: (1) allowed students to concentrate better on instructional tasks; (2) reduced managerial tasks; (3) aided in the prevention off-task behaviors. Another critical component was the frequency of individual feedback, which kept students more active and engaged in class activities. Smaller class sizes appear more beneficial especially for less experienced teachers, due to the increase in the delivery of individual feedback

Discomfort luminance level of head-mounted displays depending on the adapting luminance

The Images in an immersive head-mounted display (HMD) for virtual reality provide the sole source for visual adaptation. Thus, significant, near-instantaneous increases in luminance while viewing an HMD can result in visual discomfort. Therefore, the current study investigated the luminance change necessary to induce this discomfort. Based on the psychophysical experiment data collected from 10 subjects, a prediction model was derived using four complex images and one neutral image, with four to six levels of average scene luminance. Result showed that maximum area luminance has a significant correlation with the discomfort luminance level than average, median, or maximum pixel luminance. According to the prediction model, the discomfort luminance level of a head-mounted display was represented as a positive linear function in log(10) units using the previous adaptation luminance when luminance is calculated as maximum area luminance

Molecular Weight Dependent Glucose Lowering Effect of Low Molecular Weight Chitosan Oligosaccharide (GO2KA1) on Postprandial Blood Glucose Level in SD Rats Model

Abstract This research investigated the effect of enzymatically digested low molecular weight (MW) chitosan oligosaccharide on type 2 diabetes prevention. Three different chitosan oligosaccharide samples with varying MW were evaluated in vitro for inhibition of rat small intestinal α-glucosidase and porcine pancreatic α-amylase (GO2KA1; \u3c1000 Da, GO2KA2; 1000–10,000 Da, GO2KA3; MW \u3e 10,000 Da). The in vitro results showed that all tested samples had similar rat α-glucosidase inhibitory and porcine α-amylase inhibitory activity. Based on these observations, we decided to further investigate the effect of all three samples at a dose of 0.1 g/kg, on reducing postprandial blood glucose levels in Sprague-Dawley (SD) rat model after sucrose loading test. In the animal trial, all tested samples had postprandial blood glucose reduction effect, when compared to control, however GO2KA1 supplementation had the strongest effect. The glucose peak (Cmax) for GO2KA1 and control was 152 mg/dL and 193 mg/dL, respectively. The area under the blood glucose-time curve (AUC) for GO2KA1 and control was 262 h mg/dL and 305 h mg/dL, respectively. Furthermore, the time of peak plasma concentration of blood glucose (Tmax) for GO2KA1 was significantly delayed (0.9 h) compared to control (0.5 h). These results suggest that GO2KA1 could have a beneficial effect for blood glucose management relevant to diabetes prevention in normal and pre-diabetic individuals. The suggested mechanism of action is via inhibition of the carbohydrate hydrolysis enzyme α-glucosidase and since GO2KA1 (MW \u3c 1000 Da) had higher in vivo effect, we hypothesize that it is more readily absorbed and might exert further biological effect once it is absorbed in the blood stream, relevant to blood glucose management