Factors (not) affecting what students do with computers and internet at home

This paper presents the results of an analysis of secondary students’ computer use, aimed at understanding how different factors influence the profile of activities carried out by students with computers. The analysis is based on the data from a national study aimed at measuring students’ Information and Communication Technology (ICT) skills for learning. A factor analysis was carried out to categorize students’ activities with computers and several indexes were constructed to define the comparison groups. Finally, a multiple linear regression analysis was performed to explain the frequency of the activities. Results show that students with access to computers at home mainly perform activities categorized as Socializing, Academic, Gaming and Production and that although the absolute frequency of these activities differs across groups, the profiles of computer use are surprisingly similar for groups based on students’ socio-economic group, experience with ICT, and self-confidence in the use of ICT. The only variable that discriminates user profiles is gender. Based on these findings, it can be claimed that Chilean secondary students with access to computers at home tend to show a rather homogenous computer-use profile, once access is equated.     

Effect of dual-attention task on attack and defensive actions in fencing

The objectives of this study were to investigate the effect that the presence of two stimuli that require two different responses (dual-attention) has both, on offensive reaction-response time to a light stimulus, and on defensive response time when the stimulus is a real fencing attack. Twenty-five elite fencers and a fencing master were included in the study. The equipment included four force plates adapted to a scaffold that served as a fencing piste. Two force plates were placed, at the start position, under the fencer’s feet and another two plates were placed under the master’s feet. The results demonstrate that choice reaction time to visual stimuli increases in dual-task conditions with respect to simple reaction time, whereas the mean horizontal force tends to decrease in dual-task. However, when the stimulus was an opponent’s movement, dual-task conditions did not have any effect on the time required to initiate a defensive action. The changes in reaction time when real movements were used as stimuli challenge the validity of the reaction time to visual stimuli paradigm as a predictor of performance in fencing. Also, the results obtained demonstrate that perceptual and attentional processes play a major role in fencer performance in real competition.     

Activity profile of top-class association football referees in relation to fitness-test performance and match standard

The aim of this study was to examine the kinematic activity profiles, cardiovascular responses and physical fitness of top-class football referees (n=11) during the FIFA Confederations Cup 2005. Computerised match-analyses (n=9) were performed with a two-dimensional photogrammetric video system, and the cardiovascular demand imposed on the referees (n=12) was measured using heart rate recordings. Total distance covered was 10,218, s=643 m of which 3531, s=510 m was covered at high intensities (>3.6 m.s(-1)). Both total distance covered (r2=0.59; P=0.02) and high-intensity activities (r2=0.44; P=0.05) were related to the distance covered by the ball in the same match. The referees ran at high speed 37% further (P=0.01) in the actual tournament than during under-17 top-level officiating. After the 5-min interval during which high-speed running peaked, in the following 5 min the performance was reduced by 19% (P=0.01) in relation to the mean of the game. Mean heart rate was 161, s=9 b.min(-1) (86, s=3% of maximal heart rate (HRmax)). Mean heart rate (expressed as percentage of HRmax) was related in part (r2=0.36; P<0.01) to the number of high-intensity activities performed in the same 5-min interval. The results of this study show that: (1) kinematic activity profiles of top-class referees can be influenced by the distance covered by the ball; (2) the amount of high-speed running (>5 m.s(-1)) best describes the physical performance of referees; (3) heart rate recording can be a useful tool to determine the most intense periods of a match and (4) the new fitness tests adopted by FIFA were poor predictors of match activities.     

Cell-in-cell phenomenon in urinary sediment: a case report

The internalization of apoptotic cells by non-phagocytic cells has been observed in different tissues and could be an important mechanism for the elimination of dying cells. Here, we describe a probable event of phagocytosis of apoptotic cells mediated by urothelial cells in urinary sediment. A 90-years-old male patient was admitted unconscious to the hospital, visible signs included: pale skin and dry mucous membranes, presumptively diagnosed as dehydration. Blood test revealed anaemia (haemoglobin 130 g/L) and hyperglycaemia (glucose 7.8 mmol/L), urinalysis showed a picture of urinary tract infection (leukocyturia and bacteriuria). The microscopic analysis of urinary sediment revealed the presence of urothelial cells and leukocytes internalized in urothelial cells. Anti-CD68 (membrane marker of macrophages) was tested by immunocytochemistry and a negative result was observed. Based on the findings phagocytosis of apoptotic cells mediated by urothelial cells was identified. This phenomenon can be observed in urinary sediment and should not be confused with a neoplastic process since it is a physiological event of cell elimination.     

The Use of Clinical Reasoning Skills in the Setting of Uncertainty: A Case of Trial Femoral Head Migration

Clinical skills and medical knowledge enable physicians to overcome the uncertainty of emergent and rare clinical scenarios. Recently, a growing emphasis on evidence-based medicine (EBM) has flooded medical curricula of universities across the globe with guideline-based material, and while it has given teachers and students new tools to improve medical education, clinical reasoning must be reaffirmed in its capacity to provide physicians with the ability to solve unexpected clinical scenarios. Anatomical education in medical school should have two main objectives: to acquire anatomical knowledge and to develop the skill of applying that knowledge in clinical scenarios. The authors present a clinical scenario in which an unexpected and rare complication occurred during a routine elective hip replacement surgery. The general surgeon presiding over the case, also an anatomy professor, solved the problem using clinical reasoning and anatomical knowledge. It was a clear example of how clinical reasoning is key in approaching unprecedented, rare, or unknown complications. The intention of this scenario is to remind colleagues and medical schools that, although EBM is the standard, educators must uphold sound clinical reasoning to best prepare health care providers for their careers.