How to Measure the Game Experience? Analysis of the Factor Structure of Two Questionnaires

We describe and report the analysis of two widely used questionnaires to measure the player experience in digital games. In order to contribute to the further validation and meaningful application of the PENS and GEQ we examined the underlying factorial structure of both questionnaires. Four hundred and forty-seven participants played two different games and rated them on a set of various variables including the PENS and GEQ. Consistent with previous research we gained additional insight into optimization of both measurements. While the factor structure of the PENS appears to be consistent and invariant across two different games, the GEQ reveals weaknesses in fulfilling these requirements

Online Playtesting With Crowdsourcing: Advantages and Challenges

Answering important design questions and delivering actionable insights within a couple of days is invaluable. Traditional playtests are often time consuming, expensive and deliver insights based on only a small sample of participants. Crowdsourced playtests may deliver comparable quality of feedback with less resources. However, several aspects have to be considered in order to receive meaningful and actionable results. Based on our experience, we provide five recommendations to ensure data quality and prevent fraud. Taken together, this suggests that crowd-sourced playtesting is a promising alternative for indie, non-profit and academic Games User Research

Technical note: A collision prediction tool using Blender.

Non-coplanar radiotherapy treatment techniques on C-arm linear accelerators have the potential to reduce dose to organs-at-risk in comparison with coplanar treatment techniques. Accurately predicting possible collisions between gantry, table and patient during treatment planning is needed to ensure patient safety. We offer a freely available collision prediction tool using Blender, a free and open-source 3D computer graphics software toolset. A geometric model of a C-arm linear accelerator including a library of patient models is created inside Blender. Based on the model, collision predictions can be used both to calculate collision-free zones and to check treatment plans for collisions. The tool is validated for two setups, once with and once without a full body phantom with the same table position. For this, each gantry-table angle combination with a 2° resolution is manually checked for collision interlocks at a TrueBeam system and compared to simulated collision predictions. For the collision check of a treatment plan, the tool outputs the minimal distance between the gantry, table and patient model and a video of the movement of the gantry and table, which is demonstrated for one use case. A graphical user interface allows user-friendly input of the table and patient specification for the collision prediction tool. The validation resulted in a true positive rate of 100%, which is the rate between the number of correctly predicted collision gantry-table combinations and the number of all measured collision gantry-table combinations, and a true negative rate of 89%, which is the ratio between the number of correctly predicted collision-free combinations and the number of all measured collision-free combinations. A collision prediction tool is successfully created and able to produce maps of collision-free zones and to test treatment plans for collisions including visualisation of the gantry and table movement

The ecological forecast horizon, and examples of its uses and determinants

Forecasts of ecological dynamics in changing environments are increasingly important, and are available for a plethora of variables, such as species abundance and distribution, community structure and ecosystem processes. There is, however, a general absence of knowledge about how far into the future, or other dimensions (space, temperature, phylogenetic distance), useful ecological forecasts can be made, and about how features of ecological systems relate to these distances. The ecological forecast horizon is the dimensional distance for which useful forecasts can be made. Five case studies illustrate the influence of various sources of uncertainty (e.g. parameter uncertainty, environmental variation, demographic stochasticity and evolution), level of ecological organisation (e.g. population or community), and organismal properties (e.g. body size or number of trophic links) on temporal, spatial and phylogenetic forecast horizons. Insights from these case studies demonstrate that the ecological forecast horizon is a flexible and powerful tool for researching and communicating ecological predictability. It also has potential for motivating and guiding agenda setting for ecological forecasting research and development

Biodiversity increases and decreases ecosystem stability

International audienc

CMS physics technical design report : Addendum on high density QCD with heavy ions

Peer reviewe

Specific T cells restore the autophagic flux inhibited by Mycobacterium tuberculosis in human primary macrophages

Autophagy inhibits survival of intracellular Mycobacterium tuberculosis when induced by rapamycin or interferon \u3b3 (IFN-\u3b3), but it remains unclear whether M. tuberculosis itself can induce autophagy and whether T cells play a role in M. tuberculosis-mediated autophagy. The aim of this study was to evaluate the impact of M. tuberculosis on autophagy in human primary macrophages and the role of specific T cells in this process

Track Reconstruction with Cosmic Ray Data at the Tracker Integration Facility

The subsystems of the CMS silicon strip tracker were integrated and commissioned at the Tracker Integration Facility (TIF) in the period from November 2006 to July 2007. As part of the commissioning, large samples of cosmic ray data were recorded under various running conditions in the absence of a magnetic field. Cosmic rays detected by scintillation counters were used to trigger the readout of up to 15\,\% of the final silicon strip detector, and over 4.7~million events were recorded. This document describes the cosmic track reconstruction and presents results on the performance of track and hit reconstruction as from dedicated analyses