Normative, Passionate, or Problematic? Identification of Adolescent Gamer Subtypes Over Time

Background and aims: For most youngsters, gaming is a fun and innocent leisure activity. However, some adolescents are prone to develop problematic gaming behavior. It is therefore important to have a comprehensive understanding of psychosocial and game-related characteristics that differentiate highly engaged gamers from problematic gamers. To that end, this study evaluated the stability and consistency of Internet gaming criteria (as suggested by the DSM-5) and psychosocial characteristics in a two-wave longitudinal study including 1928 young adolescents (mean age = 13.3 years, SD = 0.91, 57% boys). Methods: A confirmatory factor analysis revealed good stability of the Internet gaming disorder (IGD) construct over time. Latent class analyses revealed three classes for boys (recreational, engaged, and problematic) and two classes for girls (recreational and engaged). Results: Significant differences between classes emerged for problem criteria (conflict and problems in social life), gaming duration, impulsivity, social competence, and attention/hyperactivity. The absence of a problematic gaming class for girls suggests that girls are less likely to develop problematic gaming behavior. Discussion: The IGD criteria as proposed by the DSM-5 are a helpful tool to identify problematic gamers, although the results of this study suggest that using a strict cut-off point might result in false positives, particularly for boys. Problem criteria appeared to be the most sensitive and specific in identifying the problematic gamer, whereas escapism criteria were the least specific and sensitive. Careful consideration of the current proposed criteria to identify problematic gaming behavior could benefit the research and clinical field

VALIDATION OF A 5-DOF INSTRUMENTED SPEED SKATE; TOWARDS A POWER METER FOR SPEED SKATING

Speed skates are the most important part of equipment of a speed skater, where weight, rocker and bend are just a few characteristics that are to a high degree individualized. This poses a challenge for any type of research in speed skating where forces have to be measured in a reliable manner. For this purpose, a 5 degrees of freedom (DoF) instrumented speed skate (VU-Skate) has been designed and validated, weighing only 130 gram extra. Skaters use their own blades and shoes, something skaters are very keen on. A calibration tool has been developed to calibrate the 5 DoF. The quality of the data has been validated in 2 ways: 1. With the use of force plates and 2. By comparing the signals to another (also newly developed) Ultra-light Forces sensor. The results are remarkably good. This is the first step in being able to measure power continuously during each stroke

Bringing science and pragmatism together a tiered approach for modelling toxicological impacts in LCA

Goal, Scope and Background: The EU 5th framework project OMNIITOX will develop models calculating characterisation factors for assessing the potential toxic impacts of chemicals within the framework of LCA. These models will become accessible through a web-based information system. The key objective of the OMNIITOX project is to increase the coverage of substances by such models. In order to reach this objective, simpler models which need less but available data, will have to be developed while maintaining scientific quality. Methods. Experience within the OMNIITOX project has taught that data availability and quality are crucial issues for calculating characterisation factors. Data availability determines whether calculating characterisation factors is possible at all, whereas data quality determines to what extent the resulting characterisation factors are reliable. Today, there is insufficient knowledge and/or resources to have high data availability as well as high data quality and high model quality at the same time. Results: The OMNIITOX project is developing two inter-related models in order to be able to provide LCA impact assessment characterisation factors for toxic releases for as broad a range of chemicals as possible: 1) A base model representing a state-of-the-art multimedia model and 2) a simple model derived from the base model using statistical tools. Discussion. A preliminary decision tree for using the OMNIITOX information system (IS) is presented. The decision tree aims to illustrate how the OMNIITOX IS can assist an LCA practitioner in finding or deriving characterisation factors for use in life cycle impact assessment of toxic releases. Conclusions and Outlook: Data availability and quality are crucial issues when calculating characterisation factors for the toxicity impact categories. The OMNIITOX project is developing a tiered model approach for this. It is foreseen that a first version of the base model will be ready in late summer of 2004, whereas a first version of the simple base model is expected a few months late

How to detect late-onset inborn errors of metabolism in patients with movement disorders - A modern diagnostic approach

We propose a modern approach to assist clinicians to recognize and diagnose inborn errors of metabolism (IEMs) in adolescents and adults that present with a movement disorder. IEMs presenting in adults are still largely unexplored. These disorders receive little attention in neurological training and daily practice, and are considered complicated by many neurologists. Adult-onset presentations of IEMs differ from childhood-onset phenotypes, which may lead to considerable diagnostic delay. The identification of adult-onset phenotypes at the earliest stage of the disease is important, since early treatment may prevent or lessen further brain damage. Our approach is based on a systematic review of all papers that concerned movement disorders due to an IEM in patients of 16 years or older. Detailed clinical phenotyping is the diagnostic cornerstone of the approach. An underlying IEM should be suspected in particular in patients with more than one movement disorder, or in patients with additional neurological, psychiatric, or systemic manifestations. As IEMs are all genetic disorders, we recommend next-generation sequencing (NGS) as the first diagnostic approach to confirm an IEM. Biochemical tests remain the first choice in acute-onset or treatable IEMs that require rapid diagnosis, or to confirm the metabolic diagnosis after NGS results. With the use of careful and systematic clinical phenotyping combined with novel diagnostic approaches such as NGS, the diagnostic yield of late-onset IEMs will increase, in particular in patients with mild or unusual phenotypes.</p

A New Type of Metal Recognition by Human T Cells: Contact Residues for Peptide-independent Bridging of T Cell Receptor and Major Histocompatibility Complex by Nickel

In spite of high frequencies of metal allergies, the structural basis for major histocompatibility complex (MHC)-restricted metal recognition is among the unanswered questions in the field of T cell activation. For the human T cell clone SE9, we have identified potential Ni contact sites in the T cell receptor (TCR) and the restricting human histocompatibility leukocyte antigen (HLA)-DR structure. The specificity of this HLA-DR–promiscuous VA22/VB17+ TCR is primarily harbored in its α chain. Ni reactivity is neither dependent on protein processing in antigen-presenting cells nor affected by the nature of HLA-DR–associated peptides. However, SE9 activation by Ni crucially depends on Tyr29 in CDR1α, an N-nucleotide–encoded Tyr94 in CDR3α, and a conserved His81 in the HLA-DR β chain. These data indicate that labile, nonactivating complexes between the SE9 TCR and most HLA-DR/peptide conjugates might supply sterically optimized coordination sites for Ni ions, three of which were identified in this study. In such complexes Ni may effectively bridge the TCR α chain to His81 of most DR molecules. Thus, in analogy to superantigens, Ni may directly link TCR and MHC in a peptide-independent manner. However, unlike superantigens, Ni requires idiotypic, i.e., CDR3α-determined TCR amino acids. This new type of TCR–MHC linkage might explain the high frequency of Ni-reactive T cells in the human population

Comparing league formats with respect to match importance in Belgian football

Recently, most clubs in the highest Belgian football division have become convinced that the format of their league should be changed. Moreover, the TV station that broadcasts the league is pleading for a more attractive competition. However, the clubs have not been able to agree on a new league format, mainly because they have conflicting interests. In this paper, we compare the current league format, and three other formats that have been considered by the Royal Belgian Football Association. We simulate the course of each of these league formats, based on historical match results. We assume that the attractiveness of a format is determined by the importance of its games; our importance measure for a game is based on the number of teams for which this game can be decisive to reach a given goal. Furthermore, we provide an overview of how each league format aligns with the expectations and interests of each type of club

OPTIMAL VELOCITY PROFILES FOR VAULT

The aim of this study was to determine which kinematic characteristics may be used as a performance indicator(s) for vault. Over 600 vaults (299 men and 216 Women, see Table 1) were recorded and analyzed using footage of 3 high-speed cameras taken at the 2010 Rotterdam Artistic Gymnastics World Championships. The kinematics were correlated with the judge’s outcome score: type of vault, difficulty and final score. The correlation coefficients between velocity at takeoff and final judges’ scores were r = 0.60 for men and r = 0.52 for women