Students' understandings about animal skeletons

Surprisingly few studies have looked at people's understanding of skeletons. Most of the work in this field that has been done has only involved children's understanding of human skeletons. This study looks at students' understandings of the structure of animal (including human) skeletons. A crosssectional approach was used involving a total of 175 students in England from six different age groups (ranging from 4 year olds to 20 year olds). Students were presented, on separate occasions, with specimens of a brown rat, a starling and a herring and asked to draw what they thought was inside each specimen. On a final occasion, they were also asked to draw what they thought was inside themselves. Repeated inspections of the completed drawings allowed us to construct a seven point scale of 'skeletal understanding'. Our analysis shows the extent to which student understanding increases with age and the degree to which pupils know more about human than other skeletons. The findings are interpreted with reference to current trends in English science curricula and pedagogy. We comment in particular on the current inability of most students to see the skeleton as a functional, integrated whole.     

Editorial

This issue of the International Journal of Public Opinion Researchassembles six contributions—three articles and three researchnotes—that represent the diversity of subjects, methods,and research sites that we aim at. The first article is by agroup of (mostly) Ohio State University scholars (Lindsay H.Hoffman, Carroll J. Glynn, Michael E. Huge, Rebecca Border Sietman,and Tiffany Thomson) who used two surveys about a school districtballot issue to study the process of opinion formation. Drawingon     

Police power

He (the constable) will be civil and obliging to all people of every class and rank. He must be particularly cautious not to interfere idly or unnecessarily in order to make a display of his authority. … if he does his duty in a quiet and determined manner such conduct will probably excite the well-disposed of the bystanders to assist him if he requires them…particular care is to be taken that the constables of the police do not form false notions of their powers and duties. Initial regulations of the Metropolitan Police, 1829.     

Similarity of science textbooks: A content. Analysis

The investigator completed a content analysis of the astronomy portion of science texts at three grade levels (4th, 5th, and 6th) that were produced by five different publishers. The analysis used an operant paradigm and compared the responses expected of students who used one science text to those expected of students using other science texts. The response comparisons were made both within and across grade levels. Using similarity of the responses expected of students as a basis of comparison, elementary school science texts produced by different publishers had more in common across grade levels than within grade levels. Less than 50% of the responses expected of students at one grade level were common to other science texts at the same or different grade levels.     

The effect of single and repeated bouts of prolonged cycling and circadian variation on saliva flow rate, immunoglobulin A and alpha-amylase responses

The purpose of this study was to establish the effect of exercise at different times of day on saliva flow rate, immunoglobulin A (sIgA) concentration and secretion rate, and alpha-amylase activity, and to establish how these parameters change following a second exercise bout performed on the same day. In a counterbalanced design, eight male volunteers participated in three experimental trials separated by at least 4 days. On the trial with afternoon exercise only, the participants cycled for 2 h at 60% VO2max starting at 14:00 h. On the other two trials, participants performed either two bouts of exercise at 60% VO2max for 2 h (the first started at 09:00 h and the second started at 14:00 h) or a separate resting trial. Unstimulated saliva samples were obtained 10 min before exercise, after 58 - 60 min and during the last 2 min of exercise, and at 1 h and 2 h after exercise. Venous blood samples were taken 5 min before exercise and immediately after exercise for both bouts. Participants remained fasted between 23:00 h on the day before the trials and 18:00 h on the day of the trial. Circadian variations were found in sIgA concentration, which decreased with time from its highest value in the early morning to its lowest value in the evening, and salivary alpha-amylase secretion rate, which increased from its lowest value in the morning to its highest value in the late afternoon. Cycling at 60% VO2max for 2 h significantly decreased saliva flow rate, increased sIgA concentration and alpha-amylase activity, but did not influence sIgA secretion rate. Performing prolonged cycling at different times of day did not differentially affect the salivary and plasma hormonal responses in the short term. Performance of a second prolonged exercise bout elicited a greater plasma stress hormone response but did not appear to compromise oral immunity acutely. These findings also suggest that, in terms of saliva secretion, sIgA and alpha-amylase responses, a 3 h rest is enough to recover from previous strenuous exercise. During such exercise, sympathetic stimulation appears to be strong enough to inhibit saliva flow rate; however, it appears that it does not increase sIgA output via transcytosis.