Double poling kinematic changes during the course of a long-distance race: effect of performance level

ABSTRACT

We aimed to evaluate the changes in double poling (DP) kinematics due to a long-distance cross-country skiing race in athletes with different performance levels. A total of 100 cross-country skiers, belonging to 10 different performance groups, were filmed on flat terrain 7 and 55 km after the start line, during a 58-km classical race. Cycle velocity, frequency and length decreased from the best to the lower-ranked group, while duty cycle increased (all P <.001). Between track sections, cycle velocity and length decreased, duty cycles increased (all P <.001) while frequency was unaltered (P =.782). Group*section interactions resulted for cycle velocity (P =.005). Considering all the participants together, % change in cycle velocity between sections correlated with % change in length and duty cycle (all P <.001). Thus i) skiers in better groups showed longer and more frequent cycles as well as shorter duty cycles than skiers in slower groups; ii) throughout the race all the groups maintained the same cycle frequency while decreasing cycle velocity and length; iii) better groups showed a lower reduction in cycle velocity. Individually, a low reduction in cycle velocity during the race related to the capacity to maintain long cycles and short duty cycles.     

A comparison of updating processes in children good or poor in arithmetic word problem-solving

This study examines the updating ability of poor or good problem solvers. Seventy-eight fourth-graders, 43 good and 35 poor arithmetic word problem-solvers, performed the Updating Test used in Palladino et al. [Palladino, P., Cornoldi, C., De Beni, R., and Pazzaglia F. (2002). Working memory and updating processes in reading comprehension. Memory and Cognition, 29, 344–354.]. The participants listened to wordlists, each comprising 12 words referring to objects or animals of different sizes. At the end of each list participants were asked to recall the 3 or 5 words denoting the smallest objects/animals in the list. Results show that poor problem-solvers recalled fewer correct words and made more intrusion errors (recall of non-target words) than good problem-solvers. Results support the hypothesis that the ability to select and update relevant, and suppress irrelevant information, is related to problem-solving, even when the influence of reading comprehension is controlled for. With reference to Baddeley's, and other recent WM models [Miyake, A., and Shah, P. (Eds.), (1999). Models of working memory: Mechanisms of active maintenance and executive control. New York: Cambridge University Press.], our results point to the idea that problem-solving relies on the central executive for processing and updating information contained in the problems.     

Early Evidence of Modular Templates Used to Draw Human Figures on Mural Paintings: The Etruscan Tomba degli Scudi in Tarquinia

ABSTRACT

During recent conservation work carried out on the Etruscan mural paintings in the Tomba degli Scudi, (Tarquinia, 4th C. BCE), the study of the execution techniques led to an amazing discovery: human figures were composed using templates of single body parts. In the Tomba degli Scudi, the perfect overlap of limbs, chests, and heads was confirmed after processing rectified photogrammetric images of the wall paintings with photo editing software. The study also highlighted that such templates were probably made of rigid material and each one had three different sizes, in order to represent the hierarchical organization of the painted characters. In the past, scholars have demonstrated that templates were used to realize a number of Etruscan wall paintings. However, they had reported that only whole figures were reproduced. The notion that such templates consisted of single anatomical parts purposely created to portray figures in different poses never occurs in their studies. In fact, the use of modular templates, also called patroni and antibola, is acknowledged only from the Middle Ages onwards both in western and eastern art. Earlier evidence had never been found. This article aims to predate the use of modular shapes by about ten centuries, thus changing our knowledge of technologies whose tradition spans from the Classical Antiquity to the Middle Ages. Consequently, a new approach to the study of transfer techniques of preparatory drawings in Etruscan wall paintings is established. Furthermore, this article shows that, as in the Middle Ages, the size of such templates was scaled up or down to create hierarchies among the painted characters.     

Acute effects of two different tennis sessions on dorsal and lumbar spine of adult players

The aim of the study was to evaluate the dorsal and lumbar spine of expert and recreational tennis players before (pre) and after (post) two different training sessions. The sample consisted of 17 male tennis players, nine expert and eight recreational males (age 21.2 ± 1.6 years). We assessed the back surface by rasterstereography pre and post two different training sessions both lasting 1.5 h: a standard training and a specific over-shoulder shots training session, respectively. Lordotic and kyphotic angle, length, imbalance, inclination for trunk, pelvic torsion, left and right lateral deviation and surface rotation were measured. Tennis expertise (expert versus recreational) significantly affected the surface rotation and right lateral deviation (P < 0.05). Trunk length was affected by intervention (pre versus post) (P < 0.05). Left lateral deviation differed both for type of session (session 1 versus session 2) and intervention (P < 0.001, P < 0.05). Expert tennis players had higher values on surface rotation and right lateral deviation, around or just above physiological values (0–5° and 0–5 mm, respectively). Type of session significantly affected left lateral deviation, indicating that over-shoulder shots lead to a higher stress for the spine; the workload produced by both single sessions led to a shortening effect on trunk length. A single training session can induce acute modifications in some parameters of dorsal and lumbar spine of players.     

READING MATHEMATICS REPRESENTATIONS: AN EYE-TRACKING STUDY

We use eye tracking as a method to examine how different mathematical representations of the same mathematical object are attended to by students. The results of this study show that there is a meaningful difference in the eye movements between formulas and graphs. This difference can be understood in terms of the cultural and social shaping of human perception, as well as in terms of differences between the symbolic and graphical registers.

     

The effects of two different correction strategies on the snatch technique in weightlifting

Improving motor skills represents one of the major issues in motor control and motor learning literature. The aim of this study was to investigate which of two strategies, method of amplification of error (MAE) or direct instruction (DI), would be more beneficial for error correction of the snatch technique. Thirty well-trained male weightlifters were randomly assigned to one of three training conditions (MAE, DI and Control). The experiment took place in only one practice session in which each lifter performed 3 pretraining trials, 8 training intervention trials, and 3 post-training trials, and a retention test session after 1 week. An optoelectronic motion capture system was used to measure the kinematic parameters of the weightlifting performance. After the training intervention, data showed that the MAE group revealed a greater improvement in several kinematic parameters when compared to the DI and Control groups, and the benefits derived from its application were still present 1 week later in the retention test. Nevertheless, the findings of the present study should be interpreted with caution due to the relatively small sample size; further research will also be necessary to evaluate the effects of MAE with different ability levels and other sport skills. The present findings could have practical implications for sport psychology and physical education because while practice is obviously necessary for improving learning, the efficacy of the learning process is essential in enhancing learners’ motivation and sport enjoyment.     

Characteristics of Italian art restoration firms and factors influencing their adoption of laser technology

Given the limited number of studies on this topic, the aim of this study is to better understand the characteristics of art restoration firms in Italy, with particular reference to their use of innovative technologies such as laser technology. The paper is supported by a survey conducted in a sample of 100 companies. The factors that have led firms to adopt or resist the adoption of the laser were identified and analysed. The results show that the main determinants of laser adoption are collaborative activities between the firms and universities and specific requests made by public institutions to use this technology.

The Representation of Virtual Reality in Education

Students' opinions about the opportunities and the implications of VR in instruction were investigated by administering a questionnaire to humanities and engineering undergraduates. The questionnaire invited participants to rate a series of statements concerning motivation and emotion, skills, cognitive styles, benefits and learning outcomes associated with the use of VR in education. The representation which emerged was internally consistent and articulated into specific dimensions. It was not affected by gender, by the previous use of VR software, or by the knowledge of the main topics concerning the introduction of IT in instruction. Also the direct participation in a training session based on an immersive VR experience did not influence such a representation, which was partially modulated by the kind of course attended by students.     

Adaptability and Grit: Foundations for Their Joint Contribution to Students' Academic and Nonacademic Outcomes

Adaptability (adjustment to new and uncertain situations) and grit (perseverance and passion for long-term goals) both sustain students, but their joint contribution has never been explored, and recent studies propose they could compose a single factor. In this study we aim to test whether (i) they actually belong to a single overarching factor as recently posited by the Triarchic Model of Grit and (ii) they have specific effects on different outcomes. We show that, in a sample of 602 students (11–18 years old), perseverance of effort, consistency of interests (the two facets of grit), and adaptability are distinct factors, that uniquely contribute to the outcomes considered (academic self-efficacy, achievement emotions, learning goals, self-regulated learning, achievement, and life satisfaction). Perseverance resulted as the strongest predictor, followed by adaptability and consistency. Conscientiousness was positively related to all three. We conclude that adaptability and grit are two separate but correlated factors that can promote a host of positive outcomes.     

Crowd science: The organization of scientific research in open collaborative projects

A growing amount of scientific research is done in an open collaborative fashion, in projects sometimes referred to as “crowd science”, “citizen science”, or “networked science”. This paper seeks to gain a more systematic understanding of crowd science and to provide scholars with a conceptual framework and an agenda for future research. First, we briefly present three case examples that span different fields of science and illustrate the heterogeneity concerning what crowd science projects do and how they are organized. Second, we identify two fundamental elements that characterize crowd science projects – open participation and open sharing of intermediate inputs – and distinguish crowd science from other knowledge production regimes such as innovation contests or traditional “Mertonian” science. Third, we explore potential knowledge-related and motivational benefits that crowd science offers over alternative organizational modes, and potential challenges it is likely to face. Drawing on prior research on the organization of problem solving, we also consider for what kinds of tasks particular benefits or challenges are likely to be most pronounced. We conclude by outlining an agenda for future research and by discussing implications for funding agencies and policy makers.