Microparticle movements in optical funnels and pods

Three-dimensional microparticle movements induced by laser beams with a funnel- and tubular pod-like structure, in the neighbourhood of the focal plane of an optical trapping setup, are experimentally studied. The funnel and pod beams constructed as coherent superpositions of helical Laguerre-Gaussian modes are synthesized by a computer generated hologram using a phase-only spatial light modulator. Particle tracking is achieved by in-line holography method which allows an accurate position measurement. It is experimentally demonstrated that the trapped particle follows different trajectories depending on the orbital angular momentum density of the beam. In particular applying the proposed pod beam the particle rotates in opposite directions during its movement in the optical trap. Possible applications of these single-beam traps for volumetric optical particle manipulation are discussed

Análisis de tráfico multicast de video H264/Theora en redes Wi-Fi IEEE 802.11ac

En los últimos años el tráfico de video ha crecido en forma exponencial, especialmente en los dispositivos móviles. Conocer el comportamiento del mismo y los requisitos necesarios de la red, ayudan a los administradores de la red a una mejor implementación. En este trabajo se propone un experimento de tráfico de video multicast en una red de laboratorio real como test bed. Se usa una topología en redes cableadas e inalámbricas con clientes inalámbricos trabajando en la norma IEEE 802.11ac. El tráfico de video se codificará en H264 y Theora, para evaluar y comprender el impacto sobre el tráfico de la red. Se analizará midiendo y comparando distintas métricas como cantidad de paquetes y bytes, espacios intertramas, tamaños de paquetes y tasa de bits efectiva para cada tipo de códec, etc. Además, se plantea un análisis estadístico de distribución de tramas. Este trabajo es una continuación de experimentaciones realizadas sobre redes cableadas para tráfico de video con codecs H261, H263 y H264. Las conclusiones del trabajo ayudarán a determinar las configuraciones a tener en cuenta para una adecuada gestión de redes similares y un uso eficiente de los recursos disponibles, sin comprometer el rendimiento y la QoS esperada.Eje: Arquitectura, Redes y Sistemas Operativos.Red de Universidades con Carreras en Informática (RedUNCI

Análisis de tráfico multicast de video H264/Theora en redes Wi-Fi IEEE 802.11ac

En los últimos años el tráfico de video ha crecido en forma exponencial, especialmente en los dispositivos móviles. Conocer el comportamiento del mismo y los requisitos necesarios de la red, ayudan a los administradores de la red a una mejor implementación. En este trabajo se propone un experimento de tráfico de video multicast en una red de laboratorio real como test bed. Se usa una topología en redes cableadas e inalámbricas con clientes inalámbricos trabajando en la norma IEEE 802.11ac. El tráfico de video se codificará en H264 y Theora, para evaluar y comprender el impacto sobre el tráfico de la red. Se analizará midiendo y comparando distintas métricas como cantidad de paquetes y bytes, espacios intertramas, tamaños de paquetes y tasa de bits efectiva para cada tipo de códec, etc. Además, se plantea un análisis estadístico de distribución de tramas. Este trabajo es una continuación de experimentaciones realizadas sobre redes cableadas para tráfico de video con codecs H261, H263 y H264. Las conclusiones del trabajo ayudarán a determinar las configuraciones a tener en cuenta para una adecuada gestión de redes similares y un uso eficiente de los recursos disponibles, sin comprometer el rendimiento y la QoS esperada.Eje: Arquitectura, Redes y Sistemas Operativos.Red de Universidades con Carreras en Informática (RedUNCI

Estudio experimental de tráfico de video en redes IPv6 multicast IEEE 802.11ac

The growing number of multimedia users involves an exponential increase in bandwidth requirements on networks. Consumers are increasingly demanding in terms of quality and performance of products based on video. This paper proposes an experiment of multicast video traffic in a network of a real laboratory as test bed, with clients working in the IEEE 802.11ac standard, and using IPv6. The videos were encoded in H.264, H.265, VP8 and Theora. And the experiments were carried out using a trailer of the movie Star Trek, and alternately for contrast, a video of a videoconference using Adobe Connect, of the same duration. This work is a continuation of experience made on wired networks for video traffic. The conclusions of the work will help to determine the configurations to be taken into account for the adequate management of similar networks and efficient use of resources available, without compromising the performance and QoS expected.XIV Workshop Arquitectura, Redes y Sistemas Operativos.Red de Universidades con Carreras en Informátic

Estudio experimental de tráfico de video en redes IPv6 multicast IEEE 802.11ac

The growing number of multimedia users involves an exponential increase in bandwidth requirements on networks. Consumers are increasingly demanding in terms of quality and performance of products based on video. This paper proposes an experiment of multicast video traffic in a network of a real laboratory as test bed, with clients working in the IEEE 802.11ac standard, and using IPv6. The videos were encoded in H.264, H.265, VP8 and Theora. And the experiments were carried out using a trailer of the movie Star Trek, and alternately for contrast, a video of a videoconference using Adobe Connect, of the same duration. This work is a continuation of experience made on wired networks for video traffic. The conclusions of the work will help to determine the configurations to be taken into account for the adequate management of similar networks and efficient use of resources available, without compromising the performance and QoS expected.XIV Workshop Arquitectura, Redes y Sistemas Operativos.Red de Universidades con Carreras en Informátic

The evolution of the ventilatory ratio is a prognostic factor in mechanically ventilated COVID-19 ARDS patients

Background: Mortality due to COVID-19 is high, especially in patients requiring mechanical ventilation. The purpose of the study is to investigate associations between mortality and variables measured during the first three days of mechanical ventilation in patients with COVID-19 intubated at ICU admission. Methods: Multicenter, observational, cohort study includes consecutive patients with COVID-19 admitted to 44 Spanish ICUs between February 25 and July 31, 2020, who required intubation at ICU admission and mechanical ventilation for more than three days. We collected demographic and clinical data prior to admission; information about clinical evolution at days 1 and 3 of mechanical ventilation; and outcomes. Results: Of the 2,095 patients with COVID-19 admitted to the ICU, 1,118 (53.3%) were intubated at day 1 and remained under mechanical ventilation at day three. From days 1 to 3, PaO2/FiO2 increased from 115.6 [80.0-171.2] to 180.0 [135.4-227.9] mmHg and the ventilatory ratio from 1.73 [1.33-2.25] to 1.96 [1.61-2.40]. In-hospital mortality was 38.7%. A higher increase between ICU admission and day 3 in the ventilatory ratio (OR 1.04 [CI 1.01-1.07], p = 0.030) and creatinine levels (OR 1.05 [CI 1.01-1.09], p = 0.005) and a lower increase in platelet counts (OR 0.96 [CI 0.93-1.00], p = 0.037) were independently associated with a higher risk of death. No association between mortality and the PaO2/FiO2 variation was observed (OR 0.99 [CI 0.95 to 1.02], p = 0.47). Conclusions: Higher ventilatory ratio and its increase at day 3 is associated with mortality in patients with COVID-19 receiving mechanical ventilation at ICU admission. No association was found in the PaO2/FiO2 variation

La multitraducció als estàndards català i valencià: el cas de Harry Potter i la pedra filosofal

En aquest article, en primer lloc definim la multitraducció i fem una classificació selectiva dels principals productes multitraduïts en llengua catalana. Després de situar la multitraducció com a objecte d’estudi de la sociologia de la traducció, analitzem el polisistema de la traducció en llengua catalana tot fent un repàs pels cosistemes lingüístic, politicoeconòmic i comunicativocultural, que determinen d’una o altra manera la multitraducció. Seguidament, presentem el cas de la multitraducció de Harry Potter i la pedra filosofal tot fent una anàlisi comparativa de les versions catalana i valenciana i analitzant la recepció que va tindre en l’àmbit acadèmic i literari. Per acabar, definim quines relacions s’estableixen en el fenomen de la multitraducció en llengua catalana entre els diferents cosistemes i quina va ser la política de traducció i les normes lingüisticotextuals que es van seguir en fer la multitraducció de l’estudi de cas.First of all, a definition of multitranslation is given and a selective classification of the main multitranslated products in Catalan is offered. After that, multitranslation is contextualised within the sociology of translation. Then the polysystem of Catalan translation is analysed together with the linguistic, the politicoeconomical and the communicative‐cultural cosystems which influence multitranslation. Next, I present the multitranslation of Harry Potter and the Philosopher’s Stone into Valencian and a comparative analysis of both the Catalan and the Valencian versions. Then, I review the reception of the Valencian version in the academic and literary spheres. Finally, the relations among the different cosystems are defined with regards to Catalan multitranslation, and the translation policy and the textual‐linguistic norms are defined for the case study.Aquesta recerca ha rebut el suport del Ministeri de Ciència i Innovació espanyol FFI2009-08027, La subtitulación para sordos y la audiodescripción: pruebas objetivas y planes de futuro, i també de la Generalitat de Catalunya a través de 2009SGR700 i de la Universitat Autònoma de Barcelona

Invariant recognition of polychromatic images of Vibrio cholerae O1

7 pages, 5 figures.-- ©2002 Society of Photo-Optical Instrumentation Engineers.Cholera is an acute intestinal infectious disease. It has claimed many lives throughout history, and it continues to be a global health threat. Cholera is considered one of the most important emergence diseases due its relation with global climate changes. Automated methods such as optical systems represent a new trend to make more accurate measurements of the presence and quantity of this microorganism in its natural environment. Automatic systems eliminate observer bias and reduce the analysis time.We evaluate the utility of coherent optical systems with invariant correlation for the recognition of Vibrio cholerae O1. Images of scenes are recorded with a CCD camera and decomposed in three RGB channels. A numeric simulation is developed to identify the bacteria in the different samples through an invariant correlation technique. There is no variation when we repeat the correlation and the variation between images correlation is minimum. The position-, scale-, and rotation-invariant recognition is made with a scale transform through the Mellin transform. The algorithm to recognize Vibrio cholerae O1 is the presence of correlation peaks in the green channel output and their absence in red and blue channels. The discrimination criterion is the presence of correlation peaks in red, green, and blue channels.Peer reviewe