Visual scanning in sports actions: comparison between soccer goalkeepers and judo fighters

Visual search and oculomotor behaviour are believed to be very relevant for athlete performance, especially for sports requiring refined visuo-motor coordination skills. Modern coaches believe that a correct visuo-motor strategy may be part of advanced training programs. In this thesis two experiments are reported in which gaze behaviour of expert and novice athletes were investigated while they were doing a real sport specific task. The experiments concern two different sports: judo and soccer. In each experiment, number of fixations, fixation locations and mean fixation duration (ms) were considered. An observational analysis was done at the end of the paper to see perceptual differences between near and far space. Purpose: The aim of the judo study was to delineate differences in gaze behaviour characteristics between a population of athletes and one of non athletes. Aspects specifically investigated were: search rate, search order and viewing time across different conditions in a real-world task. The second study was aimed at identifying gaze behaviour in varsity soccer goalkeepers while facing a penalty kick executed with instep and inside foot. Then an attempt has been done to compare the gaze strategies of expert judoka and soccer goalkeepers in order to delineate possible differences related to the different conditions of reacting to events occurring in near (peripersonal) or far (extrapersonal) space. Judo Methods: A sample of 9 judoka (black belt) and 11 near judoka (white belt) were studied. Eye movements were recorded at 500Hz using a video based eye tracker (EyeLink II). Each subject participated in 40 sessions for about 40 minutes. Gaze behaviour was considered as average number of locations fixated per trial, the average number of fixations per trial, and mean fixation duration. Soccer Methods: Seven (n = 7) intermediate level male volunteered for the experiment. The kickers and goalkeepers, had at least varsity level soccer experience. The vision-in-action (VIA) system (Vickers 1996; Vickers 2007) was used to collect the coupled gaze and motor behaviours of the goalkeepers. This system integrated input from a mobile eye tracking system (Applied Sciences Laboratories) with an external video of the goalkeeper’s saving actions. The goalkeepers took 30 penalty kicks on a synthetic pitch in accordance with FIFA (2008) laws. Judo Results: Results indicate that experts group differed significantly from near expert for fixations duration, and number of fixations per trial. The expert judokas used a less exhaustive search strategy involving fewer fixations of longer duration than their novice counterparts and focused on central regions of the body. The results showed that in defence and attack situation expert group did a greater number of transitions with respect to their novice counterpart. Soccer Results: We found significant main effect for the number of locations fixated across outcome (goal/save) but not for foot contact (instep/inside). Participants spent more time fixating the areas in instep than inside kick and in goal than in save situation. Mean and standard error in search strategy as a result of foot contact and outcome indicate that the most gaze behaviour start and finish on ball interest areas. Conclusions: Expert goalkeepers tend to spend more time in inside-save than instep-save penalty, differences that was opposite in scored penalty kick. Judo results show that differences in visual behaviour related to the level of expertise appear mainly when the test presentation is continuous, last for a relatively long period of time and present a high level of uncertainty with regard to the chronology and the nature of events. Expert judoist performers “anchor” the fovea on central regions of the scene (lapel and face) while using peripheral vision to monitor opponents’ limb movements. The differences between judo and soccer gaze strategies are discussed on the light of physiological and neuropsychological differences between near and far space perception.

A new 3D modelling paradigm for discrete model

Until few years ago, 3D modelling was a topic confined into a professional environment. Nowadays technological innovations, the 3D printer among all, have attracted novice users to this application field. This sudden breakthrough was not supported by adequate software solutions. The 3D editing tools currently available do not assist the non-expert user during the various stages of generation, interaction and manipulation of 3D virtual models. This is mainly due to the current paradigm that is largely supported by two-dimensional input/output devices and strongly affected by obvious geometrical constraints. We have identified three main phases that characterize the creation and management of 3D virtual models. We investigated these directions evaluating and simplifying the classic editing techniques in order to propose more natural and intuitive tools in a pure 3D modelling environment. In particular, we focused on freehand sketch-based modelling to create 3D virtual models, interaction and navigation in a 3D modelling environment and advanced editing tools for free-form deformation and objects composition. To pursuing these goals we wondered how new gesture-based interaction technologies can be successfully employed in a 3D modelling environments, how we could improve the depth perception and the interaction in 3D environments and which operations could be developed to simplify the classical virtual models editing paradigm. Our main aims were to propose a set of solutions with which a common user can realize an idea in a 3D virtual model, drawing in the air just as he would on paper. Moreover, we tried to use gestures and mid-air movements to explore and interact in 3D virtual environment, and we studied simple and effective 3D form transformations. The work was carried out adopting the discrete representation of the models, thanks to its intuitiveness, but especially because it is full of open challenges.

Differential activation of the lateral premotor cortex during action observation

Background Action observation leads to neural activation of the human premotor cortex. This study examined how the level of motor expertise (expert vs. novice) in ballroom dancing and the visual viewpoint (internal vs. external viewpoint) influence this activation within different parts of this area of the brain. Results Sixteen dance experts and 16 novices observed ballroom dance videos from internal or external viewpoints while lying in a functional magnetic resonance imaging scanner. A conjunction analysis of all observation conditions showed that action observation activated distinct networks of premotor, parietal, and cerebellar structures. Experts revealed increased activation in the ventral premotor cortex compared to novices. An internal viewpoint led to higher activation of the dorsal premotor cortex. Conclusions The present results suggest that the ventral and dorsal premotor cortex adopt differential roles during action observation depending on the level of motor expertise and the viewpoint.

An integrated environment for filter design

Analog filters and direct digital filters are implemented using digital signal processing techniques. Specifically, Butterworth, Elliptic, and Chebyshev filters are implemented using the Motorola 56001 Digital Signal Processor by the integration of three software packages: MATLAB, C++, and Motorola's Application Development System. The integrated environment allows the novice user to design a filter automatically by specifying the filter order and critical frequencies, while permitting more experienced designers to take advantage of MATLAB's advanced design capabilities. This project bridges the gap between the theoretical results produced by MATLAB and the practicalities of implementing digital filters using the Motorola 56001 Digital Signal Processor. While these results are specific to the Motorola 56001 they may be extended to other digital signal processors. MATLAB handles the filter calculations, a C++ routine handles the conversion to assembly code, and the Motorola software compiles and transmits the code to the processor

"What is the Value of Youth Work?" Symposium Booklet

As a group of experienced and novice youth workers, we believe that youth work is fundamentally about building trust-filled, mutually respectful relationships with young people. We create safe environments for young people to connect with other supportive adults and peers and to avoid violence in their neighborhoods and their homes. We guide those harmed by oppressive community conditions such as racism, sexism, agism, homophobia, and classism through a process of healing. As we get to know more about young people’s interests, we help them develop knowledge and skills in a variety of areas including: academic, athletic, leadership/civic, the arts, health and wellbeing, and career exploration. In short, we create transformative experiences for young people. In spite of the critical roles we play, we have largely been overlooked in youth development research, policy, and as a professional workforce. We face challenges ‘moving up’ in our careers. We get frustrated by how little money we earn. We are discouraged that despite our knowledge and experience we are not invited to the tables where youth funding, programming, and policy decisions are made. It is true—many of us do not have formal training or degrees in youth work—a reality which at times we regret. Yet, as our colleague communicates in the accompanying passage (see below), we resent that formal education is required for us to get ahead, particularly because we question whether we need it to do our jobs more effectively. Through the “What is the Value of Youth Work?” symposium, we hope to address these concerns through a dialogue about youth work with the following objectives: • Increase awareness of the knowledge, skills, contributions, and professionalism of youth workers; • Advance a youth worker professional development model that integrates a dilemma-focused approach with principles of social justice youth development; • Launch an ongoing Worcester area Youth Worker network. This booklet provides a brief overview of the challenges in ‘professionalizing’ youth work and an alternative approach that we are advancing that puts the knowledge and expertise of youth workers at the center of professional development.

Robustness of speckle imaging techniques applied to horizontal imaging scenarios

Atmospheric turbulence near the ground severely limits the quality of imagery acquired over long horizontal paths. In defense, surveillance, and border security applications, there is interest in deploying man-portable, embedded systems incorporating image reconstruction methods to compensate turbulence effects. While many image reconstruction methods have been proposed, their suitability for use in man-portable embedded systems is uncertain. To be effective, these systems must operate over significant variations in turbulence conditions while subject to other variations due to operation by novice users. Systems that meet these requirements and are otherwise designed to be immune to the factors that cause variation in performance are considered robust. In addition robustness in design, the portable nature of these systems implies a preference for systems with a minimum level of computational complexity. Speckle imaging methods have recently been proposed as being well suited for use in man-portable horizontal imagers. In this work, the robustness of speckle imaging methods is established by identifying a subset of design parameters that provide immunity to the expected variations in operating conditions while minimizing the computation time necessary for image recovery. Design parameters are selected by parametric evaluation of system performance as factors external to the system are varied. The precise control necessary for such an evaluation is made possible using image sets of turbulence degraded imagery developed using a novel technique for simulating anisoplanatic image formation over long horizontal paths. System performance is statistically evaluated over multiple reconstruction using the Mean Squared Error (MSE) to evaluate reconstruction quality. In addition to more general design parameters, the relative performance the bispectrum and the Knox-Thompson phase recovery methods is also compared. As an outcome of this work it can be concluded that speckle-imaging techniques are robust to the variation in turbulence conditions and user controlled parameters expected when operating during the day over long horizontal paths. Speckle imaging systems that incorporate 15 or more image frames and 4 estimates of the object phase per reconstruction provide up to 45% reduction in MSE and 68% reduction in the deviation. In addition, Knox-Thompson phase recover method is shown to produce images in half the time required by the bispectrum. The quality of images reconstructed using Knox-Thompson and bispectrum methods are also found to be nearly identical. Finally, it is shown that certain blind image quality metrics can be used in place of the MSE to evaluate quality in field scenarios. Using blind metrics rather depending on user estimates allows for reconstruction quality that differs from the minimum MSE by as little as 1%, significantly reducing the deviation in performance due to user action.

Understanding "Just Enough" Computer Users: Motivation Style and Proficiency

Among daily computer users who are proficient, some are flexible at accomplishing unfamiliar tasks on their own and others have difficulty. Software designers and evaluators involved with Human Computer Interaction (HCI) should account for any group of proficient daily users that are shown to stumble over unfamiliar tasks. We define "Just Enough" (JE) users as proficient daily computer users with predominantly extrinsic motivation style who know just enough to get what they want or need from the computer. We hypothesize that JE users have difficulty with unfamiliar computer tasks and skill transfer, whereas intrinsically motivated daily users accomplish unfamiliar tasks readily. Intrinsic motivation can be characterized by interest, enjoyment, and choice and extrinsic motivation is externally regulated. In our study we identified users by motivation style and then did ethnographic observations. Our results confirm that JE users do have difficulty accomplishing unfamiliar tasks on their own but had fewer problems with near skill transfer. In contrast, intrinsically motivated users had no trouble with unfamiliar tasks nor with near skill transfer. This supports our assertion that JE users know enough to get routine tasks done and can transfer that knowledge, but become unproductive when faced with unfamiliar tasks. This study combines quantitative and qualitative methods. We identified 66 daily users by motivation style using an inventory adapted from Deci and Ryan (Ryan and Deci 2000) and from Guay, Vallerand, and Blanchard (Guay et al. 2000). We used qualitative ethnographic methods with a think aloud protocol to observe nine extrinsic users and seven intrinsic users. Observation sessions had three customized phases where the researcher directed the participant to: 1) confirm the participant's proficiency; 2) test the participant accomplishing unfamiliar tasks; and 3) test transfer of existing skills to unfamiliar software.

Self-assessment insufficiently predicts performance in emergency skills

Background: Residents demonstrate a broad range of performance levels for clinical skills, with some at an inadequate level. Adequate self-assessment is important for life long learning. However, its accuracy is questioned extensively. The aim of this study was to evaluate how far the residents’ self-assessment predicts their performance in an expert assessment of emergency skills. Summary of work: Twelve skills were identified as being relevant for the emergency duties of residents in smaller hospitals. Fifteen first-year residents from the departments of internal medicine and general surgery at a district hospital rated their performance on a questionnaire (self-assessment). This was followed by a structured, practical in vivo assessment by an anaesthesiologist (expert assessment). For both, a visual analogue scale from 0 to 10 was used, on which 0 stands for novice and 10 for expert. Predictive validity was described by Spearman’s correlation, which was significant in 3 out of 12 skills only. Median correlation (r) was 0.50 (range 0.16 to 0.93). Conclusion: At the beginning of postgraduate training, self-assessment alone is not sufficient to guide self-directed learning. Take-home message: At the beginning of their residency, physicians need structured feedback in emergency skills which can be offered by anaesthesiologists.

Pleomorphic adenoma of the parotid: formal parotidectomy or limited surgery?

BACKGROUND Optimal surgery for pleomorphic adenoma of the parotid is controversial. In the present review, we discuss the advantages and disadvantages of the various approaches after addressing the surgical pathology of the parotid pleomorphic adenoma capsule and its influence on surgery. DATA SOURCES PubMed literature searches were performed to identify original studies. CONCLUSIONS Almost all pleomorphic adenomas can be effectively treated by formal parotidectomy, but the procedure is not mandatory. Extracapsular dissection is a minimal margin surgery; therefore, in the hands of a novice or occasional parotid surgeon, it may result in higher rates of recurrence. Partial superficial parotidectomy may be a good compromise. The tumor is removed with a greater cuff of healthy parotid tissue than in extracapsular dissection. This may minimize the recurrence rate. On the other hand, the removal of healthy parotid tissue compared with formal parotidectomy is limited, thus minimizing complications such as facial nerve dysfunction and Frey syndrome.

Application of Cognitive Engineering Principles to the Redesign of a Dichotomous Identification Key for Parasitology

Dichotomous identification keys are used throughout biology for identification of plants, insects, and parasites. However, correct use of identification keys can be difficult as they are not usually intended for novice users who may not be familiar with the terminology used or with the morphology of the organism being identified. Therefore, we applied cognitive engineering principles to redesign a parasitology identification key for the Internet. We addressed issues of visual clutter and spatial distance by displaying a single question couplet at a time and by switching to the appropriate next couplet after the user made a choice. Our analysis of the original paper-based key versus the Web-based approach found that of 26 applicable cognitive engineering principles, the paper key did not meet 4 (15%) and partially met 11 (42%). In contrast, the redesigned key met 100% of 32 applicable cognitive engineering principles.

Expertise in Clinical Psychology. The Effects of University Training and Practical Experience on Expertise in Clinical Psychology

How do university training and subsequent practical experience affect expertise in clinical psychology? To answer this question we developed methods to assess psychological knowledge and the competence to diagnose, construct case conceptualizations, and plan psychotherapeutic treatment: a knowledge test and short case studies in a first study, and a complex, dynamically evolving case study in the second study. In our cross-sectional studies, psychology students, trainees in a certified postgraduate psychotherapist curriculum, and behavior therapists with more than 10 years of experience were tested (100 in total: 20 each of novice, intermediate, and advanced university students, postgraduate trainees, and therapists). Clinical knowledge and competence increased up to the level of trainees but unexpectedly decreased at the level of experienced therapists. We discuss the results against the background of expertise research and the training of clinical psychologists (in Germany). Important factors for the continuing professional development of psychotherapists are proposed.

The Quiet Eye in Motor Performance and Learning – Functional and Theoretical Considerations

High precision in motor skill performance, in both sport and other domains (e.g. surgery and aviation), requires the efficient coupling of perceptual inputs (e.g. vision) and motor actions. A particular gaze strategy, which has received much attention within the literature, has been shown to predict both inter- (expert vs. novice) and intra-individual (successful vs. unsuccessful) motor performance (see Vine et al., 2014). Vickers (1996) labelled this phenomenon the quiet eye (QE) which is defined as the final fixation before the initiation of the crucial phase of movement. While the positive influence of a long QE on accuracy has been revealed in a range of different motor skills, there is a growing number of studies suggesting that the relationship between QE and motor performance is not entirely monotonic. This raises interesting questions regarding the QE’s purview, and the theoretical approaches explaining its functionality. This talk aims to present an overview of the issues described above, and to discuss contemporary research and experimental approaches to examining the QE phenomenon. In the first part of the talk Dr. Vine will provide a brief and critical review of the literature, highlighting recent empirical advancements and potential directions for future research. In the second part, Dr. Klostermann will communicate three different theoretical approaches to explain the relationship between QE and motor performance. Drawing upon aspects of all three of these theoretical approaches, a functional inhibition role for the QE (related to movement parameterisation) will be proposed.

Nonlesions, misdiagnoses, missed diagnoses, and other interpretive challenges in fish histopathology studies: a guide for investigators, authors, reviewers, and readers.

Differentiating salient histopathologic changes from normal anatomic features or tissue artifacts can be decidedly challenging, especially for the novice fish pathologist. As a consequence, findings of questionable accuracy may be reported inadvertently, and the potential negative impacts of publishing inaccurate histopathologic interpretations are not always fully appreciated. The objectives of this article are to illustrate a number of specific morphologic findings in commonly examined fish tissues (e.g., gills, liver, kidney, and gonads) that are frequently either misdiagnosed or underdiagnosed, and to address related issues involving the interpretation of histopathologic data. To enhance the utility of this article as a guide, photomicrographs of normal and abnormal specimens are presented. General recommendations for generating and publishing results from histopathology studies are additionally provided. It is hoped that the furnished information will be a useful resource for manuscript generation, by helping authors, reviewers, and readers to critically assess fish histopathologic data.

Los profesores principiantes enseñan historia

El objetivo de este trabajo es conocer cómo se incorporan a la labor docente, y en ese contexto cómo enseñan historia, los profesores noveles egresados de los profesorados en historia de la UNGS (Universidad Nacional de General Sarmiento) y del ISFD no 42 (Instituto Superior de Formación Docente). Son considerados docentes noveles o principiantes aquellos profesores que se encuentran en los primeros tres años del ejercicio de la profesión. La información aquí presentada fue recogida a través de una investigación de tipo cualitativa realizada entre el IDH (Instituto del Desarrollo Humano), perteneciente a la Universidad Nacional de General Sarmiento y el Instituto Superior de Formación Docente no 42 de San Miguel, provincia de Buenos Aires Este proyecto, realizado entre los años 2008 y 2010, fue dirigido por la doctora Gabriela Diker, quien en ese momento se desempeñaba como coordinadora del área de formación del IDH de la UNGS. Preguntas como: ¿cuáles son las dificultades que deben afrontar los profesores principiantes?, ¿qué respuestas elaboran ante dichas dificultades?, ¿cómo desarrollan el proceso de enseñanza de la historia?, ¿qué recursos y materiales utilizan para ello?, ¿cómo influyen las trayectorias de formación docente sobre las prácticas que desarrollan los profesores principiantes? servirán de guía a fin de poder indagar la trayectoria docente en este período inicial para luego caracterizarlo, analizarlo y finalmente volver a evaluar los alcances y límites de la información brindada por la investigación. Un punto interesante será comparar los trayectos formativos por los que atravesaron los graduados de ambas instituciones, teniendo en cuenta que un grupo de graduados se formó en una institución universitaria y el otro colectivo de profesores proviene de una institución terciaria. El objetivo es identificar si las instituciones formadoras de base ejercen alguna influencia que permita diferenciar comparativamente las prácticas de un grupo respecto del otro

Los profesores principiantes enseñan historia

El objetivo de este trabajo es conocer cómo se incorporan a la labor docente, y en ese contexto cómo enseñan historia, los profesores noveles egresados de los profesorados en historia de la UNGS (Universidad Nacional de General Sarmiento) y del ISFD no 42 (Instituto Superior de Formación Docente). Son considerados docentes noveles o principiantes aquellos profesores que se encuentran en los primeros tres años del ejercicio de la profesión. La información aquí presentada fue recogida a través de una investigación de tipo cualitativa realizada entre el IDH (Instituto del Desarrollo Humano), perteneciente a la Universidad Nacional de General Sarmiento y el Instituto Superior de Formación Docente no 42 de San Miguel, provincia de Buenos Aires Este proyecto, realizado entre los años 2008 y 2010, fue dirigido por la doctora Gabriela Diker, quien en ese momento se desempeñaba como coordinadora del área de formación del IDH de la UNGS. Preguntas como: ¿cuáles son las dificultades que deben afrontar los profesores principiantes?, ¿qué respuestas elaboran ante dichas dificultades?, ¿cómo desarrollan el proceso de enseñanza de la historia?, ¿qué recursos y materiales utilizan para ello?, ¿cómo influyen las trayectorias de formación docente sobre las prácticas que desarrollan los profesores principiantes? servirán de guía a fin de poder indagar la trayectoria docente en este período inicial para luego caracterizarlo, analizarlo y finalmente volver a evaluar los alcances y límites de la información brindada por la investigación. Un punto interesante será comparar los trayectos formativos por los que atravesaron los graduados de ambas instituciones, teniendo en cuenta que un grupo de graduados se formó en una institución universitaria y el otro colectivo de profesores proviene de una institución terciaria. El objetivo es identificar si las instituciones formadoras de base ejercen alguna influencia que permita diferenciar comparativamente las prácticas de un grupo respecto del otro