TC multicorte (TCMC) cardiaca: aplicaciones clínicas

La introducción de los equipos de TC multicorte y el desarrollo de técnicas de adquisición de imágenes con sincronización electrocardiográfica y reconstrucción retrospectiva han permitido que la TC multicorte cardiaca se pueda considerar hoy en día una técnica no invasiva muy útil para el estudio de la patología cardiaca en la práctica clínica diaria. La valoración de las arterias coronarias es una de las principales aplicaciones clínicas de esta técnica diagnóstica e incluye la detección y cuantificación del calcio coronario, la coronariografía por TC multicorte (estudio de la anatomía coronaria, variantes anatómicas y anomalías del origen y trayecto), la valoración angiográfica de la permeabilidad de injertos aortocoronarios y endoprótesis vasculares y la caracterización de las placas de ateroma. Los nuevos programas de reconstrucción y postprocesamiento permiten obtener, además, parámetros de morfología y contracción miocárdica y función cardiaca. Otras aplicaciones clínicas incluyen la caracterización de masas cardiacas intracavitarias y la valoración del pericardio.Since the introduction of last generation multislice MSCT systems and the development of simultaneous electrocardiographic-tracing image acquisition and retrospective reconstruction techniques into clinical routine, cardiac MSCT has been considered a very useful non-invasive technique for the study of cardiac pathology in the daily clinical practice. One of the main clinical applications of this diagnostic technique is the evaluation of the coronary arteries including detection and quantification of coronary calcium, multislice CT coronary angiography (anatomy, anatomical variants and anomalies of the origin and course), the angiographic evaluation of the patency of aortocoronary by-pass grafts and coronary stents, and plaque characterization. The new reconstruction and postprocessing programs allow to obtain, in addition, parameters of myocardial morphology and contraction and cardiac function. Other clinical applications include the characterization of cardiac masses and the evaluation of the pericardium

Epistemic and social scripts in computer-supported collaborative learning

Collaborative learning in computer-supported learning environments typically means that learners work on tasks together, discussing their individual perspectives via text-based media or videoconferencing, and consequently acquire knowledge. Collaborative learning, however, is often sub-optimal with respect to how learners work on the concepts that are supposed to be learned and how learners interact with each other. One possibility to improve collaborative learning environments is to conceptualize epistemic scripts, which specify how learners work on a given task, and social scripts, which structure how learners interact with each other. In this contribution, two studies will be reported that investigated the effects of epistemic and social scripts in a text-based computer-supported learning environment and in a videoconferencing learning environment in order to foster the individual acquisition of knowledge. In each study the factors ‘epistemic script’ and ‘social script’ have been independently varied in a 2×2-factorial design. 182 university students of Educational Science participated in these two studies. Results of both studies show that social scripts can be substantially beneficial with respect to the individual acquisition of knowledge, whereas epistemic scripts apparently do not to lead to the expected effects

In the eye of the beholder:promoting learner-centric design to develop mobile games for learning

Out of the project EMuRgency a game-based learning environment evolved, which trains school children in providing reanimation and cardiopulmonary resuscitation (CPR). The application gets players to act as if they were in a real case of emergency. This paper reports on a formal usability study conducted with two different groups of learners, regular learners and learners with special educational needs (SEN). With the study we compared the two groups of learners with regard to game usability and effectiveness of the intervention. Our intention was to better understand the different needs and requirements to learning materials that game designer need to take into consideration in order to make the learning experience successful for both groups. A total of 89 children played the game simulation. Results showed differences in perception and effectiveness of individual mechanisms for the two groups with regard to usability or switching between tasks and mobile device.This publication was partly financed by the European Regional Development Fund (ERDF), regions of the Euregio Meuse-Rhine and the participating institutions under the INTERREG IVa program (EMR.INT4-1.2.-2011-04/070, http://www.emurgency.eu)

True and intentionally fabricated memories

The aim of the experiment reported here was to investigate the processes underlying the construction of truthful and deliberately fabricated memories. Properties of memories created to be intentionally false - fabricated memories - were compared to properties of memories believed to be true - true memories. Participants recalled and then wrote or spoke true memories and fabricated memories of everyday events. It was found that true memories were reliably more vivid than fabricated memories and were nearly always recalled from a first person perspective. In contrast, fabricated differed from true memories in that they were judged to be reliably older, were more frequently recalled from a third person perspective, and linguistic analysis revealed that they required more cognitive effort to generate. No notable differences were found across modality of reporting. Finally, it was found that, intentionally fabricated memories were created by recalling and then ‘editing’ true memories. Overall, these findings show that true and fabricated memories systematically differ, despite the fact that both are based on true memories

Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

Relationship of edge localized mode burst times with divertor flux loop signal phase in JET

A phase relationship is identified between sequential edge localized modes (ELMs) occurrence times in a set of H-mode tokamak plasmas to the voltage measured in full flux azimuthal loops in the divertor region. We focus on plasmas in the Joint European Torus where a steady H-mode is sustained over several seconds, during which ELMs are observed in the Be II emission at the divertor. The ELMs analysed arise from intrinsic ELMing, in that there is no deliberate intent to control the ELMing process by external means. We use ELM timings derived from the Be II signal to perform direct time domain analysis of the full flux loop VLD2 and VLD3 signals, which provide a high cadence global measurement proportional to the voltage induced by changes in poloidal magnetic flux. Specifically, we examine how the time interval between pairs of successive ELMs is linked to the time-evolving phase of the full flux loop signals. Each ELM produces a clear early pulse in the full flux loop signals, whose peak time is used to condition our analysis. The arrival time of the following ELM, relative to this pulse, is found to fall into one of two categories: (i) prompt ELMs, which are directly paced by the initial response seen in the flux loop signals; and (ii) all other ELMs, which occur after the initial response of the full flux loop signals has decayed in amplitude. The times at which ELMs in category (ii) occur, relative to the first ELM of the pair, are clustered at times when the instantaneous phase of the full flux loop signal is close to its value at the time of the first ELM