Editorial

Ohne Zusammenfassung     

Reduction of mental distress in the dissection course by introducing the body donor experience through anatomical demonstrations of organ systems

The practice of dissection teaches students not only the foundations of anatomical knowledge but also encourages the development of professional competencies. Yet, the dissection of cadavers in the gross anatomy course can be a stress factor for medical students. There are a minor proportion of students who demonstrate strong emotional reactions in anticipation of being confronted with a cadaver. Therefore, in 2008, the authors implemented a voluntary course entitled, “Anatomical demonstrations of organ systems” (AD‐OS) in advance of the dissection course to ease this psychological burden. The question of whether attendees of AD‐OS showed less mental distress at the start of the dissection course compared with those that had not or only infrequently visited AD‐OS was addressed. AD‐OS attendees assessed their expected mental distress using a five‐point Likert scale before starting the dissection course and a second time at the end of their first day, after they had been confronted with a cadaver. AD‐OS was evaluated as excellent and the majority of students participated actively during teaching sessions. Overall, female students showed higher levels of mental distress. AD‐OS attendees assessed themselves as being less burdened by mental distress than members of the control group. Longitudinal analysis revealed that students who visited AD‐OS showed a marked decrease of their mental distress level, comparing prospective and retrospective ratings. This was significantly (P < 0.001; Z = ?6.061) different from nonattendees or those who visited AD‐OS only infrequently. AD‐OS satisfied its intended teaching goals and proved that a step‐by‐step introduction of dissection through anatomical demonstrations helped to reduce the mental distress of students. Future studies are planned to measure mental distress with objective instruments. Anat Sci Educ © 2012 American Association of Anatomists.     

Impact of Secondary Students’ Content Knowledge on Their Communication Skills in Science

The expert blind spot (EBS) hypothesis implies that even some experts with a high content knowledge might have problems in science communication because they are using the structure of the content rather than their addressee’s prerequisites as an orientation. But is that also true for students? Explaining science to peers is a crucial part of cooperative learning methods such as the “jigsaw method”. Our study examined the relationship between science communication competence (SCC) and content knowledge (CK) of 10th-grade students (N = 213). Using latent class analysis, we identified two types of students with a different relationship between CK and SCC. Using path analysis, we found that the first type of 109 students primarily used their science CK as the “resource” for addressee-oriented science communication and both their SCC and their CK were correlated with each other. For the second type of 104 students (who used other resources), their CK even had a small negative effect on their SCC. Using t tests, we found that those students primarily using their CK as the resource for communication performed significantly worse in the communication test than did those students who used other resources. Using the EBS hypothesis, we suggest that students’ CK might have ambiguous effects in communication if the content structure—rather than their addressee’s prior knowledge—is used as the primary orientation for communication. We suggest that an effective use of cooperative learning techniques in classroom requires a special prior training for their science communication skills.     

Akute infektiöse Diarrhoe

Ohne Zusammenfassung     

Effects of wearing lower leg compression sleeves on locomotion economy

The purpose of this investigation was to assess the effect of compression sleeves on muscle activation cost during locomotion. Twenty-two recreationally active men (age: 25 ± 3 years) ran on a treadmill at four different speeds (ordered sequence of 2.8, 3.3, 2.2, and 3.9 m/s). The tests were performed without (control situation, CON) and while wearing specially designed lower leg compression sleeves (SL). Myoelectric activity of five lower leg muscles (tibialis anterior, fibularis longus, lateral and medial head of gastrocnemius, and soleus) was captured using Surface EMG. To assess muscle activation cost, the cumulative muscle activity per distance travelled (CMAPD) of the CON and SL situations was determined. Repeated measures analyses of variance were performed separately for each muscle. The analyses revealed a reduced lower leg muscle activation cost with respect to test situation for SL for all muscles (p < 0.05, η_p² > 0.18). The respective significant reductions of CMAPD values during SL ranged between 4% and 16% and were largest at 2.8 m/s. The findings presented point towards an improved muscle activation cost while wearing lower leg compression sleeves during locomotion that have potential to postpone muscle fatigue.     

Oxygen uptake during mini trampoline exercise in normal-weight,endurance-trained adults and in overweight-obese,inactive adults: A proof-of-concept study

Objectives: To examine cardiorespiratory exertion during mini trampoline exercises of different intensities in both endurance-trained athletes and overweight-obese adults. Methods: Physically healthy participants (Group A: normal-weight, endurance-trained athletes; Group B: inactive, overweight-obese adults) participated in two measurement appointments and three training sessions in between appointments, in which participants familiarized themselves with the use of the mini trampoline and the execution of the exercises. The primary outcome was the ?O_2peak for each of the six mini trampoline exercises relative to the ?O_2peak as established during an all-out exercise test on a bike ergometer during the first measurement appointment. Secondary outcomes were average ?O₂ as well as maximum and average heart rate. Results: The six mini trampoline exercises generated ?O_2peak values between 42% and 81% in the endurance-trained athletes and between 58% and 87% in the overweight-obese participants, both in relation to the bike ergometer ?O_2peak. Average ?O₂ values ranged from 35% to 69% (endurance-trained athletes) and from 48% to 71% (overweight-obese participants), depending on exercise. Average heart rate likewise lay in a range that can be categorized as moderate-to-vigorous aerobic exercise for both groups. A moderate-to-strong correlation (0.658 to 0.875, depending on exercise) between bike ergometer ?O_2peak and mini trampoline ?O_2peak was found for all six exercises. Conclusions: Mini trampoline exercise has the potential to produce training intensities that concur with established exercise guidelines. The exercise intensity is self-adjusting and allows for an effective and safe workout for different users with a wide range of fitness levels.     

The Benefits of Fixed Item Parameter Calibration for Parameter Accuracy in Small Sample Situations in Large‐Scale Assessments

Large‐scale assessments such as the Programme for International Student Assessment (PISA) have field trials where new survey features are tested for utility in the main survey. Because of resource constraints, there is a trade‐off between how much of the sample can be used to test new survey features and how much can be used for the initial item response theory (IRT) scaling. Utilizing real assessment data of the PISA 2015 Science assessment, this article demonstrates that using fixed item parameter calibration (FIPC) in the field trial yields stable item parameter estimates in the initial IRT scaling for samples as small as n = 250 per country. Moreover, the results indicate that for the recovery of the county‐specific latent trait distributions, the estimates of the trend items (i.e., the information introduced into the calibration) are crucial. Thus, concerning the country‐level sample size of n = 1,950 currently used in the PISA field trial, FIPC is useful for increasing the number of survey features that can be examined during the field trial without the need to increase the total sample size. This enables international large‐scale assessments such as PISA to keep up with state‐of‐the‐art developments regarding assessment frameworks, psychometric models, and delivery platform capabilities.