88 research outputs found

    Caracterización y comparación de mutaciones en tumores primarios, tejido metastásico y DNA circulante en pacientes con cáncer de mama metastásico

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    El cáncer de mama es la neoplasia más frecuentemente diagnosticada en mujeres en los países occidentales. Los mayores avances el en tratamiento del cáncer de mama están relacionados con el desarrollo de terapias dirigidas como tamoxifeno frente al receptor estrogénico (RE) y trastuzumab para el cáncer de mama HER2 positivo.La utilización de tecnologías de secuenciación de nueva generación (NGS) en proyectos cooperativos internacionales como el Atlas del Genoma del Cáncer (TCGA) y el Consorcio Internacional para el estudio del Genoma del Cáncer (ICGC) ha aportado información esencial sobre el perfil de mutaciones del cáncer de mama. Este conocimiento ha llevado a la identificación de potenciales dianas terapéuticas para las cuales existen tratamientos disponibles que deben ser testados en ensayos clínicos..

    RISC-based architectures for multiple robot systems

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    Several approaches to multiple robot system control are discussed. In order to simplify the study a multilayered model is proposed: a control layer which directly acts on the dynamics of the manipulators, a coordination/communication layer which makes all the manipulators work together and a programming layer which interfaces with the user. For the first layer two architectural alternatives are studied: a centralized single processor system and a distributed multiprocessor with static task assignment. For the second case an implementation based on the 1960 family of RISC processors is introduced. For the second layer three possibilities are considered: serial interface, parallel bus and local area network. The latter is carefully studied and a low cost alternative to the standard deterministic network MAP is introduced. This cell network is based on the CSMA/DCR protocol implemented on the i82596 coprocessor. Two alternatives are discussed for the programming layer: a parallel programming language based on a scene approach and a C extended language used to program elementary tasks in a robot independent way coupled with an intelligent scheduler used to assign these tasks to the robot arms at run time

    An analytical model of inter-channel interference in Bluetooth-based systems

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    One of the main advantages of the Bluetooth standard is that it provides a way to support ad-hoc connectivity between a variable number of devices at low cost. However, in situations with many Bluetooth devices that coexist in the same area the problem of channel interference may become of high importance. In this paper, we present an analysis that provides some expressions for the channel throughput and the delay that packets suffer due to possible collisions with other Bluetooth devices. The model includes the different effects of new and retransmitted packets. Both synchronized and unsynchronized systems are considered. Furthermore, although the effect of propagation losses are not explicitly considered, we show how they could be included in our model.Ministerio de Ciencia y Tecnología TIC2001-1868-C03-02Ministerio de Ciencia y Tecnología TIC2000-0087-P4-0

    A generalization of path following for mobile robots

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    Several authors have proposed some methods for applying path following in specific cases to mobile robots. When we try to extend the path following approach to the general problem several difficulties arise. We present a generalized technique to apply path following to a mobile robot with nonholonomic constraints. As an application example, we expose the case of mobile robots with a higher degree of manoeuvrability than the typical car-like robots. In particular we consider a robot that can turn around itself making a zero-radius turn; a case still not resolved as far as we know. Finally we propose a suitable control law for this example that ensures asymptotical convergence.Comisión Interministerial de Ciencia y Tecnología TER96-2056-C02-0

    A Path Following Control for Unicycle Robots

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    In this work we present a new path following control for unicycle robots that is applicable for almost all the possible desired paths and whose analysis is very straightforward. First we select the path following method that consists of two steps: choosing a ‘‘projection’’ that relates the actual posture to the desired path and imposing a ‘‘motion exigency’’ to ensure that the robot advances. A ‘‘projection’’ that considers all the error coordinates is selected and closed equations are obtained for it. The uniqueness projection is carefully analyzed and a necessary and sufficient condition is also presented. This condition shows that a slight bound on the curvature derivative of desired paths must be imposed to preserve uniqueness. It is remarkable that the selected path following is applicable for paths containing zero-radius turns, a problem that has never been resolved as far as we know. In addition, an asymptotically stable control law is found using the closed form equation of the proposed path following and the second Lyapunov method. Finally, we show the behavior of the path following and the control law through several simulated and experimental results, using a computerized wheelchair built at our research facility.Comisión Interministerial de Ciencia y Tecnología TER96-2056-C02-0

    Chrono-Scheduling; a simplified dynamic scheduling algorithm for timing predictable processors

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    We propose a simpler and latency-reduced instruction scheduler, called chronoscheduling algorithm, which avoids large and difficult instruction wake-up in order to reduce power consumption and latencies. The key idea of this scheduler is to extract and record all possible information about the future execution of an instruction during its issue, so as not to look for this information again and again during wait stages at the reservation stations. Therefore, an instruction can be issued with the information about at what cycle its operands must be captured and when it must be executed. The first implementation is targeted to processors that have constant latencies like many embedded microcontrollers, most vector processors without data cache, etc. Its main advantages are: no tags, no renaming, and much simpler waiting stations. When compared with classical dynamic schedulers, chrono-scheduling provides approximately the same CPI but with simpler overall circuitry and presumably higher clock speed (mainly because of its simplified stations).Ministerio de Ciencia y Educación TIN2006-15617-C03-03Junta de Andalucía P06-TIC-0229

    Error adaptive tracking for mobile robots

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    In mobile robots it is usual that the desired trajectory is memorized or previously generated. When following a trajectory, there are several possibilities attending to the way in which the actual robot state can be related with the whole trajectory. One of them is the extension of the servosystem approach, usually called "trajectory tracking". This is the only possibility if we need strict temporal deterministic requirements. But if not, other possibilities appear. One of them is called "path following", where the path's point to track is the "nearest" (under several conditions) to the actual robot's position. In this paper we present another method suitable for nondeterministic systems, which we may call "error adaptive tracking", because the tracking pace adapts to the errors. Its benefits and advantages are identified. Afterwards, we determine how to construct this method and we apply it to the case of SIRIUS, an advanced wheelchair. Then a control law that ensures asymptotic stability is extracted using the second Lyapunov method and under the error adaptive tracking approach. Finally, we show the benefits of the new method, comparing it with the trajectory tracking approach.Ministerio de Ciencia y Tecnología TIC-2000-0087-P4-

    Decreased event-related theta power and phase-synchrony in young binge drinkers during target detection: An anatomically-constrained MEG approach

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    Background: The prevalence of binge drinking (BD) has been on the rise in recent years. It is associated with a range of neurocognitive deficits among adolescents and young emerging adults who are especially vulnerable to alcohol use. Attention is an essential dimension of executive functioning and attentional disturbances may be associated with hazardous drinking. The aim of the study was to examine the oscillatory neural dynamics of attentional control during visual target detection in emerging young adults as a function of BD. Method: Fifty-one first-year university students (18±0.6 years) were assigned to light drinking (LD, N=26), and BD (N=25) groups based on their alcohol consumption patterns. High-density magnetoencephalography (MEG) signal was combined with structural magnetic resonance imaging (MRI) in an anatomically-constrained MEG model to estimate event-related source power in theta (4-7 Hz) frequency band. Phase-locked co-oscillations were further estimate between the principally activated regions during task performance. Results: Overall, the greatest event-related theta power was elicited by targets in the right inferior frontal cortex (rIFC) and it correlated with performance accuracy and selective attention scores. BDs exhibited lower theta power and dysregulated oscillatory synchrony to targets in the rIFC which correlated with higher levels of alcohol consumption. Conclusions: These results confirm that a highly interactive network in the rIFC subserves attentional control, revealing the importance of theta oscillations and neural synchrony for attentional capture and contextual maintenance. Attenuation of theta power and synchronous interactions in BDs may indicate early stages of suboptimal integrative processing in young, highly functioning BDsThis study was supported by the projects SPI/2010/134 and SPI/2010/051 from the Spanish Ministry of Health and Social Politics (National Plan of Drugs), and the National Institutes of Health, US, (R01-AA016624)S

    Soft real-time communications over Bluetooth under interferences from ISM devices

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    Bluetooth is a suitable technology to support soft real-time applications like multimedia streams at the personal area network level. In this paper, we analytically evaluate the worst-case deadline failure probability of Bluetooth packets under co-channel interference as a way to provide statistical guarantees when transmitting soft real-time traffic using ACL links. We consider the interference from independent Bluetooth devices, as well as from other devices operating in the ISM band like 802.11b/g and Zigbee. Finally, we show as an example how to use our model to obtain some results for the transmission of a voice stream.Ministerio de Ciencia y Tecnología TIC2001-1868-C03-0

    SIRIUS: Improving the maneuverability of powered wheelchairs

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    The indoor maneuverability of powered wheelchairs may be difficult or bothersome in several circumstances. In this paper, we describe an experimental powered wheelchair named SIRIUS, developed at the University of Seville, which introduces some simple but effective navigation aids. Special emphasis is placed on the implementation of recorded trajectory playback and in the shared control modes, i.e., the chair's guiding where both the user and the computer collaborate. Furthermore, SIRIUS is an open platform to essay another kinds of functional or navigational aids, because its hardware architecture is based on a commercial PC. This would permit many devices that are frequently needed by the chair driver to be integrated smoothly into the chair controller.Ministerio de Ciencia y Tecnología TIC-2000-0087-P4-0
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