High accuracy decoding of dynamical motion from a large retinal population

Motion tracking is a challenge the visual system has to solve by reading out the retinal population. Here we recorded a large population of ganglion cells in a dense patch of salamander and guinea pig retinas while displaying a bar moving diffusively. We show that the bar position can be reconstructed from retinal activity with a precision in the hyperacuity regime using a linear decoder acting on 100+ cells. The classical view would have suggested that the firing rates of the cells form a moving hill of activity tracking the bar's position. Instead, we found that ganglion cells fired sparsely over an area much larger than predicted by their receptive fields, so that the neural image did not track the bar. This highly redundant organization allows for diverse collections of ganglion cells to represent high-accuracy motion information in a form easily read out by downstream neural circuits.Comment: 23 pages, 7 figure

Left Ventricular Assist Devices: Impact of Flow Ratios on the Localisation of Cardiovascular Diseases Using Computational Fluid Dynamics

AbstractThe use of Left Ventricular Assistive Devices (LVADs) is increasing for people with heart failure. The present computational fluid dynamics study provides insight into the significance of the flow ratio between the cannula and the aortic root on the prediction of lesion localisation in a typical LVAD configuration, which in turn affects the design and manufacture of these devices. Three cases were studied with varying percentages of flow through the two inlets; the cannula inlet was assumed steady-state, whilst the aortic root inlet had a scaled pulsatile profile, representative of the extent of heart failure. Results suggest that as the flow exiting the heart decreases in velocity, if not orientated properly, the jet exiting the cannula graft can ‘obstruct’ flow to the innominate, common carotid and left subclavian arteries. Therefore, patients with less severe heart failure will generally experience relatively good perfusion of these arteries. However, for the more severe cases of heart failure, the orientation of the cannula graft should be such that adequate perfusion to the aforementioned arteries is maintained

The MODUS approach to formal verification

Background: Software reliability is of great importance for the development of embedded systems that are often used in applications that have requirements for safety. Since the life cycle of embedded products is becoming shorter, productivity and quality simultaneously required and closely in the process of providing competitive products Objectives: In relation to this, MODUS (Method and supporting toolset advancing embedded systems quality) project aims to provide small and medium-sized businesses ways to improve their position in the embedded market through a pragmatic and viable solution Methods/Approach: This paper will describe the MODUS project with focus on the technical methodologies that can assist formal verification and formal model checking. Results: Based on automated analysis of the characteristics of the system and by controlling the choice of the existing opensource model verification engines, model verification producing inputs to be fed into these engines. Conclusions: The MODUS approach is aligned with present market needs; the familiarity with tools, the ease of use and compatibility/interoperability remain among the most important criteria when selecting the development environment for a projec

Tourism in Gozo : policies, prospects and problems

The National Tourism Organisation does not have a specific marketing plan for Gozo. Part of the reason for this is geography and awareness - not Gozo's, but the location of our archipelago. Although we have made tremendous progress in creating market awareness of our islands in Europe and in North America, the fact remains that many people still do not know where the Maltese islands are. On a visit to England, not so long ago, I told someone I came from Malta. "Isn't it next to Hong Kong ?" he asked. He was referring to Macao. The point is that in our major source markets there is still ignorance of the whereabouts of our destination. Consequently, we feel it would be detrimental to our national tourism interests to market our islands separately. Having said that, however, Gozo - together with Comino - is an essential part of our national tourism offer. We all know what Gozo can offer to the tourist - and not only in natural beauty but also for leisure, history, culture and its very own traditions. And we certainly do stress these unique selling propositions in our international advertisement campaigns and promotional literature. Unlike Malta, Gozo is - and is perceived abroad as being - greener, more rural and generally more laid-back. Malta is 20 per cent built-up and has a much higher population density than Gozo.peer-reviewe

Modelo estadístico para la predicción de fallas potenciales en redes eléctricas de distribución

CODENSA S.A ESP. Surge en 1997 tras el proceso de capitalización de la empresa de Energía de Bogotá, encargándose del proceso de distribución y comercialización de la energía eléctrica en la capital, y en todos los municipios de Cundinamarca. Actualmente pertenece al grupo ENEL, multinacional europea que funciona en varios países y abarca gran parte de América Latina. Por tal motivo la participación del mercado en Colombia es de casi 22,36%. Uno de los principales objetivos de ENEL CODENSA S.A ESP. es involucrar apropiadamente las nuevas tecnologías con el fin de atender de manera eficiente, segura y confiable la demanda prevista en su sistema eléctrico. Es por esto que, en los sistemas de distribución, la confiabilidad está altamente relacionada con la continuidad del suministro de energía eléctrica [2], y puede expresarse por una gran variedad de índices. Adicionalmente, es necesario involucrar objetivos que se puedan evaluar teniendo en cuenta la disponibilidad del servicio a sus usuarios, parámetros de cobertura, confiabilidad, calidad, impactos ambientales y sociales. Bajo estos criterios se deben desarrollar planes de mantenimiento en la red de distribución, con el fin de alcanzar las metas que se requieran. Los principales tipos de mantenimiento que se implementan son el preventivo, el predictivo, el sistemático y el correctivo

Oncolog, Volume 37, Issue 01, January-March 1992

Clinician and chemist forge new approach to liposome research Computerized network enhances interdisdplinary patient management Neurofibromatosis: a new clinic brings new opportunitieshttps://openworks.mdanderson.org/oncolog/1037/thumbnail.jp