Radiation injury is a potentially serious complication to fluoroscopically-guided complex interventions.

Radiation-induced injury to skin is an infrequent but potentially serious complication to complex fluoroscopically-guided interventional procedures. Due to a lack of experience with such injuries, the medical community has found fluoroscopically-induced injuries difficult to diagnose. Injuries have occurred globally in many countries. Serious injuries most frequently occur on the back but have also occurred on the neck, buttocks and anterior of the chest. Severities of injuries range from skin rashes and epilation to necrosis of the skin and its underlying structures. This article reviews the characteristics of these injuries and some actions that can be taken to reduce their likelihood or seriousness.

An IEEE 802.11 energy efficient mechanism for continuous media applications

The widespread deployment of wireless mobile communications enables an almost permanent usage of portable devices, which imposes high demands on the battery of these devices. Indeed, battery lifetime is becoming one the most critical factors on the end-users satisfaction when using wireless communications. In this work, the optimized power save algorithm for continuous media applications (OPAMA) is proposed, aiming at enhancing the energy efficiency on end-users devices. By combining the application specific requirements with data aggregation techniques, {OPAMA} improves the standard {IEEE} 802.11 legacy Power Save Mode (PSM) performance. The algorithm uses the feedback on the end-user expected quality to establish a proper tradeoff between energy consumption and application performance. {OPAMA} was assessed in the OMNeT++ simulator, using real traces of variable bitrate video streaming applications, and in a real testbed employing a novel methodology intended to perform an accurate evaluation concerning video Quality of Experience (QoE) perceived by the end-users. The results revealed the {OPAMA} capability to enhance energy efficiency without degrading the end-user observed QoE, achieving savings up to 44 when compared with the {IEEE} 802.11 legacy PSM.

Professional musicians listen differently to music

INTRODUCTION: Experience-based adaptation of emotional responses is an important faculty for cognitive and emotional functioning. Professional musicians represent an ideal model in which to elicit experience-driven changes in the emotional processing domain. The changes of the central representation of emotional arousal due to musical expertise are still largely unknown. The aim of the present study was to investigate the electroencephalogram (EEG) correlates of experience-driven changes in the domain of emotional arousal. Therefore, the differences in perceived (subjective arousal via ratings) and physiologically measured (EEG) arousal between amateur and professional musicians were examined. PROCEDURE: A total of 15 professional and 19 amateur musicians listened to the first movement of Ludwig van Beethoven's 5th symphony (duration=∼7.4min), during which a continuous 76-channel EEG was recorded. In a second session, the participants evaluated their emotional arousal during listening. In a tonic analysis, we examined the average EEG data over the time course of the music piece. For a phasic analysis, a fast Fourier transform was performed and covariance maps of spectral power were computed in association with the subjective arousal ratings. RESULTS: The subjective arousal ratings of the professional musicians were more consistent than those of the amateur musicians. In the tonic EEG analysis, a mid-frontal theta activity was observed in the professionals. In the phasic EEG, the professionals exhibited an increase of posterior alpha, central delta, and beta rhythm during high arousal. DISCUSSION: Professionals exhibited different and/or more intense patterns of emotional activation when they listened to the music. The results of the present study underscore the impact of music experience on emotional reactions.

Interactive free viewpoint video streaming using prioritized network coding

In free viewpoint applications, the images are captured by an array of cameras that acquire a scene of interest from different perspectives. Any intermediate viewpoint not included in the camera array can be virtually synthesized by the decoder, at a quality that depends on the distance between the virtual view and the camera views available at decoder. Hence, it is beneficial for any user to receive camera views that are close to each other for synthesis. This is however not always feasible in bandwidth-limited overlay networks, where every node may ask for different camera views. In this work, we propose an optimized delivery strategy for free viewpoint streaming over overlay networks. We introduce the concept of layered quality-of-experience (QoE), which describes the level of interactivity offered to clients. Based on these levels of QoE, camera views are organized into layered subsets. These subsets are then delivered to clients through a prioritized network coding streaming scheme, which accommodates for the network and clients heterogeneity and effectively exploit the resources of the overlay network. Simulation results show that, in a scenario with limited bandwidth or channel reliability, the proposed method outperforms baseline network coding approaches, where the different levels of QoE are not taken into account in the delivery strategy optimization.

Self-reported attenuated psychotic-like experiences in help-seeking adolescents and their association with age, functioning and psychopathology

OBJECTIVE Self-rated attenuated psychotic-like experiences (APLEs) are increasingly used to screen for ultra-high-risk (UHR) across all ages. However, self-rated psychotic-like experiences (PLEs), in particular perception-related ones, were more frequent in children and adolescents, in which they possessed less clinical significance. We therefore explored the prevalence of different factors of APLEs in help-seeking adolescents, and their relationship with age, functioning and psychopathology METHOD As a part of the "Liberiamo il Futuro" project, help-seeking adolescents (N=171; 11-18years, 53% male) were screened with the 92-item Prodromal Questionnaire (PQ-92). A factor analysis was performed on the PQ-92 positive items (i.e., APLEs) to identify different APLE-factors. These were assessed for their association with age, functioning and psychopathology using regression analyses. RESULTS APLEs were very common in help-seeking adolescents, and formed four factors: "Conceptual Disorganization and Suspiciousness", "Perceptual Abnormalities", "Bizarre Experiences", and "Magical Ideation". Associations with age and functioning but not psychopathology were found for "Perceptual Abnormalities" that was significantly more severe in 11-12-year-olds, while "Conceptual Disorganization and Suspiciousness" was significantly related to psychopathology. CONCLUSION In line with findings on PLEs, prevalence and clinical significance of APLEs, especially perception-related ones, might depend on age and thus neurodevelopmental stage, and may fall within the normal spectrum of experience during childhood. This should be considered when screening for UHR status in younger age groups

Grenzen des Machbaren. Was Pilgerwege erfolgreich macht

Auch in Deutschland versuchen immer mehr Touristiker vom Pilgerboom zu profitieren. Die neuen Wege werden oft nur wenig genutzt. Wer versteht, was Pilgern ausmacht, kann auch erfolgreich agieren. Auf Basis eines empirischen Forschungsprojektes entfaltet der Beitrag das Spezifikum des Pilgerns als einen bestimmten Erfahrungsmodus: Pilger erfahren sich selbst eingebunden in den Zusammenhang des Seins, einen sie tragenden Grund. Es geht um ein Unverfügbares, dem sie sich überlassen, weil es Gewissheit stiftet. Dies setzt dem touristischen Inszenieren enge Grenzen. Werden diese beachtet, entstehen nachhaltige und erfahrungswirksame Pilgerwege. Schlagworte: Pilgern, Erfahrung, Körper, Natur

Adaptive Beaconless Opportunistic Routing for Multimedia Distribution

User experience on watching live videos must be satisfactory even under the inuence of different network conditions and topology changes, such as happening in Flying Ad-Hoc Networks (FANETs). Routing services for video dissemination over FANETs must be able to adapt routing decisions at runtime to meet Quality of Experience (QoE) requirements. In this paper, we introduce an adaptive beaconless opportunistic routing protocol for video dissemination over FANETs with QoE support, by taking into account multiple types of context information, such as link quality, residual energy, buffer state, as well as geographic information and node mobility in a 3D space. The proposed protocol takes into account Bayesian networks to define weight vectors and Analytic Hierarchy Process (AHP) to adjust the degree of importance for the context information based on instantaneous values. It also includes a position prediction to monitor the distance between two nodes in order to detect possible route failure.

Energy Efficient Multimedia Communications in IEEE 802.11 Networks

During the last decade wireless mobile communications have progressively become part of the people’s daily lives, leading users to expect to be “alwaysbest-connected” to the Internet, regardless of their location or time of day. This is indeed motivated by the fact that wireless access networks are increasingly ubiquitous, through different types of service providers, together with an outburst of thoroughly portable devices, namely laptops, tablets, mobile phones, among others. The “anytime and anywhere” connectivity criterion raises new challenges regarding the devices’ battery lifetime management, as energy becomes the most noteworthy restriction of the end-users’ satisfaction. This wireless access context has also stimulated the development of novel multimedia applications with high network demands, although lacking in energy-aware design. Therefore, the relationship between energy consumption and the quality of the multimedia applications perceived by end-users should be carefully investigated. This dissertation addresses energy-efficient multimedia communications in the IEEE 802.11 standard, which is the most widely used wireless access technology. It advances the literature by proposing a unique empirical assessment methodology and new power-saving algorithms, always bearing in mind the end-users’ feedback and evaluating quality perception. The new EViTEQ framework proposed in this thesis, for measuring video transmission quality and energy consumption simultaneously, in an integrated way, reveals the importance of having an empirical and high-accuracy methodology to assess the trade-off between quality and energy consumption, raised by the new end-users’ requirements. Extensive evaluations conducted with the EViTEQ framework revealed its flexibility and capability to accurately report both video transmission quality and energy consumption, as well as to be employed in rigorous investigations of network interface energy consumption patterns, regardless of the wireless access technology. Following the need to enhance the trade-off between energy consumption and application quality, this thesis proposes the Optimized Power save Algorithm for continuous Media Applications (OPAMA). By using the end-users’ feedback to establish a proper trade-off between energy consumption and application performance, OPAMA aims at enhancing the energy efficiency of end-users’ devices accessing the network through IEEE 802.11. OPAMA performance has been thoroughly analyzed within different scenarios and application types, including a simulation study and a real deployment in an Android testbed. When compared with the most popular standard power-saving mechanisms defined in the IEEE 802.11 standard, the obtained results revealed OPAMA’s capability to enhance energy efficiency, while keeping end-users’ Quality of Experience within the defined bounds. Furthermore, OPAMA was optimized to enable superior energy savings in multiple station environments, resulting in a new proposal called Enhanced Power Saving Mechanism for Multiple station Environments (OPAMA-EPS4ME). The results of this thesis highlight the relevance of having a highly accurate methodology to assess energy consumption and application quality when aiming to optimize the trade-off between energy and quality. Additionally, the obtained results based both on simulation and testbed evaluations, show clear benefits from employing userdriven power-saving techniques, such as OPAMA, instead of IEEE 802.11 standard power-saving approaches.

Trends in Human-Centric Multimedia Networking Scenarios

The evolution of wireless access technologies and mobile devices, together with the constant demand for video services, has created new Human-Centric Multimedia Networking (HCMN) scenarios. However, HCMN poses several challenges for content creators and network providers to deliver multimedia data with an acceptable quality level based on the user experience. Moreover, human experience and context, as well as network information play an important role in adapting and optimizing video dissemination. In this paper, we discuss trends to provide video dissemination with Quality of Experience (QoE) support by integrating HCMN with cloud computing approaches. We identified five trends coming from such integration, namely Participatory Sensor Networks, Mobile Cloud Computing formation, QoE assessment, QoE management, and video or network adaptation.

La filosofía de Risieri Frondizi en El punto de partida del filosofar

En este trabajo se analiza el primer libro del filósofo argentino Risieri Frondizi: El punto de partida del filosofar (1945). Frondizi presenta las bases de su programa filosófico, al que denomina empirismo total (radicalmente diferente al empirismo sensualista). Aquí juega un rol central el concepto de intencionalidad, que toma de Brentano y Husserl, pero resignificado a partir de la metafísica de Whitehead. El empirismo de Frondizi sólo puede entenderse en el sentido de que se debe partir de la realidad efectiva y no de ningún dato absoluto. Dicha realidad es la experiencia: estructura conformada por el yo, sus actividades y los objetos. Así, la filosofía es concebida como una teoría de la totalidad de la experiencia, de los elementos constituyentes y sus interrelaciones, y pretende asumir la tarea de la ontología clásica de fundamentación y síntesis de las ciencias con el fin de orientar la praxis humana.

Éxitos y desafíos en política de transporte público : análisis comparativo de las innovaciones en la prestación del servicio de transporte público de pasajeros en las ciudades de Curitiba, Brasil; Santiago de Chile, Chile y Rosario, Argentina

En esta artículo realizamos un análisis comparativo de los sistemas de servicio de transporte público de pasajeros en las ciudades de Curitiba, Brasil; Santiago de Chile, Chile y Rosario, Argentina para poder comparar las similitudes, diferencias y dificultades que presentan estos sistemas en la etapa de implementación de las políticas públicas; como así también presentar una sistematización de las políticas, instrumentos y acciones que permitieron gestionar con éxito las reestructuraciones de los sistemas de transporte y sus aportes para el desarrollo de una Política pública de transporte en el Gran Mendoza.

Notas sobre la experiencia

Muchas lecturas, textos, debates, programas de investigación en teoría de la comunicación, cultura y arte incluyen un tópico recurrente que pasa desapercibido ante las distintas interpretaciones. Éste comenzó a inquietarnos lo suficiente como para prestar mayor atención a los planteos que de él teníamos. Por esta razón decidimos ensayar en estas líneas algunas ideas recuperadas en ciertas lecturas sobre la experiencia. ¿Por qué ocuparnos de la experiencia? Desde hace un tiempo cierto discurso contemporáneo (a veces caracterizado como posmoderno) repite/repetimos que la experiencia, el sentir en el presente, cambió en una dirección totalmente nueva. No pocos debates se concentran en describir este nuevo escenario, intentando responder la pregunta disparada por la línea anterior: ¿qué direcciones tomó la experiencia contemporánea? Y por supuesto el interrogante es acompañado por otra duda con una mirada más escéptica: la experiencia contemporánea ¿es más rica o profunda que en el pasado?

Montaje de una ciudad : reflexiones acerca de una aproximación metodológica al espacio urbano

En el contexto de las sociedades capitalistas contemporáneas, el urbanismo se convierte en otro dispositivo a través del cual las imágenes mediatizan la experiencia directa en primera persona. Organizados sobre la base de un régimen de la mirada, los espacios de la ciudad se presentan como fragmentos enmascarados en la imagen de una universalidad ilusoria. Situados en la ciudad de Córdoba, observamos una transformación de la cartografía urbana que ha tenido lugar por las políticas de embellecimiento estratégico. La construcción de un centro en tanto imagen hegemónica de lo deseable conlleva su contrapartida: la emergencia de una periferia como producto de la sociosegregación, y la invisibilización de estas imágenes opuestas. Contextualizar este fenómeno nos lleva entonces a preguntarnos acerca de las posibilidades de abordarlo metodológicamente desde la propuesta benjaminiana del montaje. El presente artículo tiene como objetivo reflexionar acerca del proceso de construcción de aquella técnica, basándonos en el trabajo de campo realizado en el Buen Pastor, un paseo recreativo ubicado en la ciudad de Córdoba. Siguiendo este camino, proponemos un enfoque basado en el ejercicio de una mirada orientada a la captación plástica del acontecer social, para reunir aquellas imágenes recortadas de la experiencia y devolverlas a una totalidad posible.

Experiencia y absoluto : La respuesta de G.F.W Hegel en la Introducción a la fenomenología del espíritu a los desafíos del escepticismo de G. Schulze

Los estudios de esta tesis doctoral muestran la relación estrecha que existe en la Fenomenología del Espíritu entre el concepto hegeliano de experiencia, su concepción del absoluto y el impacto que tiene en ambos el desafío del escepticismo. La tesis general sostenida es que la confrontación de Hegel con el escepticismo es la clave de lectura más importante para la comprensión de la Introducción a la Fenomenología y por lo tanto del programa original de la obra. Más específicamente, se sostiene que la Introducción a la Fenomenología del Espíritu se encuentra filosóficamente constituida en atenta referencia a las objeciones que Gottlob Schulze había dirigido al incipiente idealismo de Jena en sus escritos de 1803 (Aforismos sobre lo Absoluto) y de 1805 (Los momentos principales del modo escéptico de pensar acerca del conocimiento humano). Se afirma aquí que Hegel revalorizó el escepticismo de Schulze, a tal punto que: a) los desafíos de Schulze son la principal provocación para un cambio de rumbo en los planes filosóficos de Hegel, esto es, el de comenzar por el problema del conocimiento antes de presentar su Lógica; b) las objeciones de Schulze constituyen los motivos decisivos que generan la ruptura entre Schelling y Hegel; c) a raíz de tales objeciones, Hegel relativiza en la Fenomenología la distinción tajante que había establecido entre antiguo y nuevo escepticismo en su escrito de 1802 (Relación del escepticismo con la filosofía); d) Hegel no sólo considera las objeciones del escéptico sino que se apropia y reformula algunas de sus ideas.En síntesis: los estudios que se exponen en esta tesis reconstruyen una polémica entre Hegel y Schulze. Esta reconstrucción puede aclarar la teoría de la experiencia que se encuentra en el texto de la Introducción a la Fenomenología.En cuanto al orden de la exposición, este trabajo doctoral comienza con una presentación de la concepción de Kant acerca de la experiencia, del límite del conocimiento humano y del absoluto, tal como aparecen en la Crítica de la Razón Pura, mostrando cómo ya en aquella obra el escepticismo juega un rol determinante (capítulo 1). A continuación, se exponen las ideas y los argumentos fundamentales del escrito hegeliano de 1802 sobre el escepticismo (capítulo 2). En el tercer capítulo se muestra la incertidumbre que tuvieron los lectores académicos, entre ellos Schulze, acerca de la autoría de la Revista Crítica de Filosofía, la cual era editada por Schelling y Hegel sin especificar la autoría de cada artículo, y en la que había sido publicado el escrito de Hegel. A esta situación se debe -según la presente tesis- que Schulze haya dirigido sus críticas a Schelling y no a Hegel. En los capítulos cuarto y quinto se exponen las tesis fundamentales que Schulze sostiene en los escritos mencionados de 1803 y 1805. El capítulo central, el sexto, consiste en un comentario de toda la Introducción a la Fenomenología a la luz del debate velado con Schulze y en atención particular al concepto hegeliano de experiencia. El último capítulo examina a grandes rasgos, a partir de lo demostrado, la concepción de Hegel sobre el escepticismo y sobre el concepto de experiencia en el resto de la Fenomenología del Espíritu. Se distingue un escepticismo estructural, que forma parte de la dinámica de la experiencia, de un escepticismo histórico que constituye una figura puntual del itinerario de la experiencia que hace la conciencia. En el mismo capítulo se considera el destino que tuvo el concepto de experiencia en el resto de la obra de Hegel y se concluye que sigue de cerca el destino de la Fenomenología y se indagan los motivos. También se examina sucintamente el papel del escepticismo en la Ciencia de la Lógica y en las Lecciones de Historia de la Filosofía. En las Conclusiones Finales de este trabajo doctoral se retoman en forma comparada y sintética las concepciones de Kant, de Schulze y de Hegel acerca de la experiencia, el límite, el absoluto y la libertad.