THE EXPRESSION PROFILE OF A GWAS DETECTED GENE (NINJ2) IN THE BRAIN OF A MOUSE MODEL OF ISCHEMIC STROKE

Stroke is the third leading cause of death and a major debilitating disease in the United States. Multiple factors, including genetic factors, contribute to the development of the disease. Genome-wide association studies (GWAS) have contributed to the identification of genetic loci influencing risk for complex diseases, such as stroke. In 2010, a GWAS of incident stroke was performed in four large prospective cohorts from the USA and Europe and identified an association of two Single Nucleotide Polymorphisms (SNPs) on chromosome 12p13 with a greater risk of ischemic stroke in individuals of European and African-American ancestry. These SNPs are located 11 Kb upstream of the nerve injury-induced gene 2, Ninjurin2 (NINJ2), suggesting that this gene may be involved in stroke pathogenesis. NINJ2 is a cell adhesion molecule induced in the distal glial cells from a sciatic-nerve injury at 7-days after injury. In an effort to ascribe a possible role of NINJ2 in stroke, we have assessed changes in the level of gene and protein expression of NINJ2 following a time-course from a transiently induced middle cerebral artery ischemic stroke in mice brains. We report an increase in the gene expression of NINJ2 in the ischemic and peri-infarct (ipsilateral) cortical tissues at 7 and 14-days after stroke. We also report an increase in the protein expression of NINJ2 in the cortex of both the ipsilateral and contralateral cortical tissues at the same time-points. We conclude that the expression of NINJ2 is regulated by an ischemic stroke in the cortex and is consistent with NINJ2 being involved in the recovery time-points of stroke.

Minimally invasive approach to lumbosacral decompression in a cadaveric canine model

AIMS To determine efficacy of a minimally invasive (MI) surgical approach using a human MI lumbar retractor for canine lumbosacral dorsal laminectomy and partial discectomy and to compare this technique to the standard open surgical (OS) approach. METHODS Lumbosacral dorsal laminectomy and partial discectomy was performed on 16 large-breed canine cadavers using either a standard OS (n=8) or MI (n=8) approach. Skin and fascial incision length, procedure time, and intraoperative complications were recorded. Postoperatively specimens were evaluated for laminectomy and discectomy dimensions, and visible damage to the cauda equina and exiting nerve roots. RESULTS Median length of skin and fascial incisions in the OS group were longer than in the MI group (p<0.001). Median laminectomy length was similar between both approaches (p=0.234) but width was greater for the MI than OS approach (p=0.002). Both approaches achieved similar partial discectomy width (p=0.279). Overall surgical time was longer for MI approaches compared to OS, with a median of 18.5 (min 15.5, max 21.8) minutes for MI compared to 14.6 (min 13.1, max 16.9) minutes for OS (p=0.001). CONCLUSIONS The MI approach reduced incision lengths while retaining comparable laminectomy and discectomy dimensions. For this in vitro model the MI approach required more time to complete, but this difference may not be relevant in clinical cases. CLINICAL RELEVANCE Dogs undergoing lumbosacral dorsal laminectomy are commonly large-breed dogs. The traditional open approach requires a large skin incision and soft tissue dissection, especially in overweight animals. A MI approach accomplishing the same surgical result while minimising soft tissue trauma could reduce post-operative pain and recovery time, and may lower wound-related complications. Clinical studies are needed to confirm postoperative benefit and assess operating times in vivo.

Escape performance of temperate king scallop, Pecten maximus under ocean warming and acidification

Among bivalves, scallops are exceptional due to their capacity to escape from predators by swimming which is provided by rapid and strong claps that are produced by the phasic muscle interspersed with tonic muscle contractions. Based on the concept of oxygen and capacity-limited thermal tolerance, the following hypothesis was tested: ocean warming and acidification (OWA) would induce disturbances in aerobic metabolic scope and extracellular acid-case status and impair swimming performance in temperate scallops. Following long-term incubation under near-future OWA scenarios [20 vs. 10 °C (control) and 0.112 kPa CO2 (hypercapnia) vs. 0.040 kPa CO2 (normocapnic control)], the clapping performance and metabolic rates (MR) were measured in resting (RMR) and fatigued (maximum MR) king scallops, Pecten maximus, from Roscoff, France. Exposure to OA, either alone or combined with warming, left MR and swimming parameters such as the total number of claps and clapping forces virtually unchanged. Only the duration of the escape response was affected by OA which caused earlier exhaustion in hyper- than in normocapnic scallops at 10 °C. While maximum MR was unaffected, warm exposure increased RMR in both normocapnic and hypercapnic P. maximus resulting in similar Q 10 values of ~2.2. The increased costs of maintenance and the observation of strongly reduced haemolymph PO2 levels indicate that at 20 °C scallops have reached the upper thermal pejus range with unbalanced capacities for aerobic energy metabolism. As a consequence, warming to 20 °C decreased mean phasic force during escape performance until fatigue. The observed prolonged recovery time in warm incubated scallops might be a consequence of elevated metabolic costs at reduced oxygen availability in the warmth.

Architectures for Video-on-Demand content distribution in managed networks

La demanda de contenidos de vídeo ha aumentado rápidamente en los últimos años como resultado del gran despliegue de la TV sobre IP (IPTV) y la variedad de servicios ofrecidos por los operadores de red. Uno de los servicios que se ha vuelto especialmente atractivo para los clientes es el vídeo bajo demanda (VoD) en tiempo real, ya que ofrece una transmisión (streaming) inmediata de gran variedad de contenidos de vídeo. El precio que los operadores tienen que pagar por este servicio es el aumento del tráfico en las redes, que están cada vez más congestionadas debido a la mayor demanda de contenidos de VoD y al aumento de la calidad de los propios contenidos de vídeo. Así, uno de los principales objetivos de esta tesis es encontrar soluciones que reduzcan el tráfico en el núcleo de la red, manteniendo la calidad del servicio en el nivel adecuado y reduciendo el coste del tráfico. La tesis propone un sistema jerárquico de servidores de streaming en el que se ejecuta un algoritmo para la ubicación óptima de los contenidos de acuerdo con el comportamiento de los usuarios y el estado de la red. Debido a que cualquier algoritmo óptimo de distribución de contenidos alcanza un límite en el que no se puede llegar a nuevas mejoras, la inclusión de los propios clientes del servicio (los peers) en el proceso de streaming puede reducir aún más el tráfico de red. Este proceso se logra aprovechando el control que el operador tiene en las redes de gestión privada sobre los equipos receptores (Set-Top Box) ubicados en las instalaciones de los clientes. El operador se reserva cierta capacidad de almacenamiento y streaming de los peers para almacenar los contenidos de vídeo y para transmitirlos a otros clientes con el fin de aliviar a los servidores de streaming. Debido a la incapacidad de los peers para sustituir completamente a los servidores de streaming, la tesis propone un sistema de streaming asistido por peers. Algunas de las cuestiones importantes que se abordan en la tesis son saber cómo los parámetros del sistema y las distintas distribuciones de los contenidos de vídeo en los peers afectan al rendimiento general del sistema. Para dar respuesta a estas preguntas, la tesis propone un modelo estocástico preciso y flexible que tiene en cuenta parámetros como las capacidades de enlace de subida y de almacenamiento de los peers, el número de peers, el tamaño de la biblioteca de contenidos de vídeo, el tamaño de los contenidos y el esquema de distribución de contenidos para estimar los beneficios del streaming asistido por los peers. El trabajo también propone una versión extendida del modelo matemático mediante la inclusión de la probabilidad de fallo de los peers y su tiempo de recuperación en el conjunto de parámetros del modelo. Estos modelos se utilizan como una herramienta para la realización de exhaustivos análisis del sistema de streaming de VoD asistido por los peers para la amplia gama de parámetros definidos en los modelos. Abstract The demand of video contents has rapidly increased in the past years as a result of the wide deployment of IPTV and the variety of services offered by the network operators. One of the services that has especially become attractive to the customers is real-time Video on Demand (VoD) because it offers an immediate streaming of a large variety of video contents. The price that the operators have to pay for this convenience is the increased traffic in the networks, which are becoming more congested due to the higher demand for VoD contents and the increased quality of the videos. Therefore, one of the main objectives of this thesis is finding solutions that would reduce the traffic in the core of the network, keeping the quality of service on satisfactory level and reducing the traffic cost. The thesis proposes a system of hierarchical structure of streaming servers that runs an algorithm for optimal placement of the contents according to the users’ behavior and the state of the network. Since any algorithm for optimal content distribution reaches a limit upon which no further improvements can be made, including service customers themselves (the peers) in the streaming process can further reduce the network traffic. This process is achieved by taking advantage of the control that the operator has in the privately managed networks over the Set-Top Boxes placed at the clients’ premises. The operator reserves certain storage and streaming capacity on the peers to store the video contents and to stream them to the other clients in order to alleviate the streaming servers. Because of the inability of the peers to completely substitute the streaming servers, the thesis proposes a system for peer-assisted streaming. Some of the important questions addressed in the thesis are how the system parameters and the various distributions of the video contents on the peers would impact the overall system performance. In order to give answers to these questions, the thesis proposes a precise and flexible stochastic model that takes into consideration parameters like uplink and storage capacity of the peers, number of peers, size of the video content library, size of contents and content distribution scheme to estimate the benefits of the peer-assisted streaming. The work also proposes an extended version of the mathematical model by including the failure probability of the peers and their recovery time in the set of parameters. These models are used as tools for conducting thorough analyses of the peer-assisted system for VoD streaming for the wide range of defined parameters.

Análisis de la influencia de la estimulación con vibraciones en la respuesta neuromuscular en competidores de esgrima

La esgrima es un deporte de combate en el que todas las acciones están dirigidas a conseguir el objetivo de la competición, que es el de tocar al contrario sin ser tocado, y para ello los tiradores/as se sirven de todas las herramientas, técnicas, tácticas y de condición física posibles a su alcance. La calidad de las acciones de los esgrimistas en competición dependerá fundamentalmente de dos de los sistemas involucrados en el proceso. Por un lado, la activación del sistema nervioso, y por otro lado la respuesta del sistema muscular. Una de las herramientas utilizadas en los últimos años para estimular el sistema neuromuscular, y que ha reportado en muchas investigaciones resultados positivos, ha sido la plataforma de vibraciones vertical. Por esto, decidimos llevar a cabo un estudio con deportistas de esgrima de competición con un protocolo de exposición aguda a las vibraciones, y medir el efecto producido por esta herramienta sobre el sistema neuromuscular a través del estudio de los cambios experimentados en los tiempos de reacción simple, tiempos de respuesta electiva y tiempos de movimiento, así como los efectos en la eficacia del tocado de esgrima analizados antes y después de recibir el estímulo vibratorio. El estudio se desarrolló con tiradores/as de competición de nivel nacional y pertenecientes al Centro de Tecnificación de la Federación de Esgrima de Castilla y León (n=38; Edad: 22 ±9,08). La muestra estaba compuesta por 12 mujeres y 26 hombres, de categorías, cadetes (13), júnior (12), y absolutos (13). El protocolo elegido fue realizado por cada participante en tres ocasiones, una inicial, otra tras pasar por una carga de estimulación en la plataforma de vibraciones, y una fase final, pasado un tiempo de recuperación de 10 minutos para comprobar el grado de disipación del efecto vibratorio. El estímulo elegido para la estimulación sobre la plataforma de vibraciones fue de una frecuencia de 50 Hz, durante un periodo de 60 segundos y con una amplitud de 4 mm. Los resultados se analizaron en función de las variables dependientes tiempo de reacción, tiempo de respuesta electiva, tiempo de movimiento, y precisión y eficacia. Estos datos se cruzaron con las variables independientes sexo, categoría, nivel deportivo y años de experiencia. El propósito del presente estudio fue el de analizar los efectos producidos por una intervención de estimulación neuromuscular mecánica en fase aguda en un grupo de tiradores/as de esgrima de competición. Los resultados mostraron que la carga de estimulación neuromuscular mecánica (ENM) aplicada en nuestro estudio provocó un discreto efecto en la respuesta neuromuscular de los tiradores participantes en la investigación. Se encontraron efectos significativos provocados por el estímulo vibratorio en las siguientes variables: en el tiempo de reacción simple se registró una mejora del 8,1%, en el tiempo de respuesta electiva a pie parado un 10%, en la precisión a pie parado un 7%, y en la eficacia a pie parado un 18,5%. Igualmente se observaron ligeras diferencias por sexos, encontrando un efecto de mayor tamaño en el grupo femenino. Es necesario resaltar que las características particulares de la muestra parecen haber influido en los resultados encontrados de forma importante. Por último, debemos destacar que el efecto residual producido por la estimulación aplicada en nuestra investigación en algún caso superó los diez minutos, ya que se hallaron efectos positivos de la estimulación neuromuscular mecánica en varios de los registros finales como hemos visto. ABSTRACT Fencing is a combat sport in which all actions are aimed at achieving the objective of the competition, which is that of touching the opponent without being touched and for this the fencers make use of all the tools, techniques, tactics and physical condition possible at their disposal. The quality of the fencers´ actions in competition will depend primarily on two of the systems involved in the process: on the one hand, the activation of the nervous system and, on the other, the response of the muscular system. One of the tools recently used to stimulate the neuromuscular system, and which has produced positive results in many research studies, has been the vertical vibration platform. Therefore, we decided to conduct a study with competition fencers with a protocol of acute exposure to vibration and to measure the effect produced by this tool on the neuromuscular system by means of the study of changes experienced in simple reaction times, the elective response times and movement times, as well as the effects on the efficacy of the fencing touch analyzed before and after receiving the vibratory stimulus. The study was conducted with fencers in national competitions and belonging to the Technification Center of the Fencing Federation of Castilla y León (n = 38), with a mean age of 22 years (SD 9.08). The sample was composed of 12 women and 26 men, by categories cadets (13), juniors (12), and seniors (13). The protocol chosen was performed by each participant on three occasions: an initial one, another after going through a stimulation load on the vibration platform, and a final phase, after a 10 minute recovery time to assess the degree of dissipation of the vibratory effect. The stimulus chosen on the vibration platform was a frequency of 50 Hz, for a period of 60 seconds and an amplitude of 4 mm. The results were analyzed according to the following dependent variables: the reaction time, the response time, the accuracy and the efficiency. This data was crossed with the independent variables: gender, category, sporting level and the years of experience. The purpose of this study was analyze the effects of neuromuscular stimulation intervention in a group of fencing competition shooters. The results showed that the mechanical neuromuscular stimulation (MNS) load applied in our study led to a modest effect on the neuromuscular response of the fencers involved in the research. Significant effects were found caused by the vibratory stimulus on the simple reaction time 8,1%, elective response time 10%, as well as the accuracy 7%, and efficiency 18,5%. We should also point out that slight differences by gender were observed, finding a greater effect in females. It should be emphasized that the specific characteristics of the sample appear to have significantly influenced the results. Finally, we should note that the residual effect produced by the stimulation applied in our research in some cases exceeded ten minutes, given that positive effects of the mechanical neuromuscular stimulation were found in several of the final scores.

Influencia del ejercicio físico desarrollado durante el embarazo en la respuesta cardiaca fetal = Influence of a physical activity program performed during pregnancy on fetal heart response

INTRODUCCIÓN: El riesgo de padecer enfermedades cardiovasculares y los índices de obesidad infantil han ido en aumento durante los últimos años empobreciendo la salud de la población. La Teoría de Barker relaciona el estado de salud de la madre con el desarrollo fetal, asociando a un deficiente estado físico y hábitos de vida negativos de la mujer embarazada con el aumento del riesgo de padecer cardiopatías en la infancia y adolescencia, así como predisponer al recién nacido a padecer sobrepeso y/u obesidad en su vida posterior. Por otro lado los estudios efectuados sobre ejercicio físico durante el embarazo reportan beneficios para salud materna y fetal. Uno de los parámetros más utilizados para comprobar la salud fetal es su frecuencia cardiaca, mediante la que se comprueba el buen desarrollo del sistema nervioso autónomo. Si se observa este parámetro en presencia de ejercicio materno podría encontrarse una respuesta crónica del corazón fetal al ejercicio materno como consecuencia de una adaptación y mejora en el funcionamiento del sistema nervioso autónomo del feto. De esta forma podría mejorar su salud cardiovascular intrauterina, lo que podría mantenerse en su vida posterior descendiendo el riesgo de padecer enfermedades cardiovasculares en la edad adulta. OBJETIVOS: Conocer la influencia de un programa de ejercicio físico supervisado en la frecuencia cardiaca fetal (FCF) en reposo y después del ejercicio materno en relación con gestantes sedentarias mediante la realización de un protocolo específico. Conocer la influencia de un programa de ejercicio físico en el desarrollo del sistema nervioso autónomo fetal, relacionado con el tiempo de recuperación de la FCF. MATERIAL Y MÉTODO: Se diseñó un ensayo clínico aleatorizado multicéntrico en el que participaron 81 gestantes (GC=38, GE=43). El estudio fue aprobado por el comité ético de los hospitales que participaron en el estudio. Todas las gestantes fueron informadas y firmaron un consentimiento para su participación en el estudio. Las participantes del GE recibieron una intervención basada en un programa de ejercicio físico desarrollado durante la gestación (12-36 semanas de gestación) con una frecuencia de tres veces por semana. Todas las gestantes realizaron un protocolo de medida de la FCF entre las semanas 34-36 de gestación. Dicho protocolo consistía en dos test llevados a cabo caminando a diferentes intensidades (40% y 60% de la frecuencia cardiaca de reserva). De este protocolo se obtuvieron las principales variables de estudio: FCF en reposo, FCF posejercicio al 40 y al 60% de intensidad, tiempo de recuperación de la frecuencia cardiaca fetal en ambos esfuerzos. El material utilizado para la realización del protocolo fue un monitor de frecuencia cardiaca para controlar la frecuencia cardiaca de la gestante y un monitor fetal inalámbrico (telemetría fetal) para registrar el latido fetal durante todo el protocolo. RESULTADOS: No se encontraron diferencias estadísticamente significativas en la FCF en reposo entre grupos (GE=140,88 lat/min vs GC= 141,95 lat/min; p>,05). Se encontraron diferencias estadísticamente significativas en el tiempo de recuperación de la FCF entre los fetos de ambos grupos (GE=135,65 s vs GC=426,11 s esfuerzo al 40%; p<,001); (GE=180,26 s vs GC=565,61 s esfuerzo al 60%; p<,001). Se encontraron diferencias estadísticamente significativas en la FCF posejercicio al 40% (GE=139,93 lat/min vs GC=147,87 lat/min; p<,01). No se encontraron diferencias estadísticamente significativas en la FCF posejercicio al 60% (GE=143,74 lat/min vs GC=148,08 lat/min; p>,05). CONLUSIÓN: El programa de ejercicio físico desarrollado durante la gestación influyó sobre el corazón fetal de los fetos de las gestantes del GE en relación con el tiempo de recuperación de la FCF. Los resultados muestran un posible mejor funcionamiento del sistema nervioso autónomo en fetos de gestantes activas durante el embarazo. ABSTRACT INTRODUCTION: The risk to suffer cardiovascular diseases and childhood obesity index has grown in the last years worsening the health around the population. Barker´s Theory related maternal health with fetal development establishing an association between a poorly physical state and an unhealthy lifestyle in the pregnant woman with the risk to suffer heart disease during childhood and adolescence, childhood overweight and/or obese is related to maternal lifestyle. By the other way researches carried out about physical exercise and pregnancy show benefits in maternal and fetal health. One of the most studied parameters to check fetal health is its heart rate, correct fetal autonomic nervous system development and work is also corroborated by fetal heart rate. Looking at this parameter during maternal exercise a chronic response of fetal heart could be found due to an adaptation and improvement in the working of the autonomic nervous system. Therefore its cardiovascular health could be enhanced during its intrauterine life and maybe it could be maintained in its posterior life descending the risk to suffer cardiovascular diseases in adult life. OBJECTIVES: To know the influence of a supervised physical activity program in the fetal heart rate (FHR) at rest, FHR after maternal exercise related to sedentary pregnant women by a FHR assessment protocol. To know the influence of a physical activity program in the development of the autonomic nervous system related to FHR recovery time. MATERIAL AND METHOD: A multicentric randomized clinical trial was design in which 81 pregnant women participated (CG=38, EG=43). The study was approved by the ethics committee of all of the hospitals participating in the study. All of the participants signed an informed consent for their participation in the study. EG participants received an intervention based on a physical activity program carried out during gestation (12-36 gestation weeks) with a three days a week frequency. All of the participants were tested between 34-36 weeks of gestation by a specific FHR assessment protocol. The mentioned protocol consisted in two test performed walking and at a two different intensities (40% and 60% of the reserve heart rate). From this protocol we obtained the main research variables: FHR at rest, FHR post-exercise at 40% and 60% intensity, and FHR recovery time at both walking test. The material used to perform the protocol were a FH monitor to check maternal HR and a wireless fetal monitor (Telemetry) to register fetal beats during the whole protocol. RESULTS: There were no statistical differences in FHR at rest between groups (EG=140,88 beats/min vs CG= 141,95 beats/min; p>,05). There were statistical differences in FHR recovery time in both walking tests between groups (EG=135,65 s vs CG=426,11 s test at 40% intensity; p<,001); (EG=180,26 s vs CG=565,61 s test at 60% intensity; p<,001). Statistical differences were found in FHR post-exercise at 40% intensity between groups (EG=139,93 beats/min vs CG=147,87 beats/min; p<,01). No statistical differences were found in FHR at rest post-exercise at 60% intensity between groups (EG=143,74 beats/min vs CG=148,08 beats/min; p>,05). CONCLUSIONS: The physical activity program performed during gestation had an influence in fetal heart of the fetus from mother in the EG related to FHR recovery time. These results show a possible enhancement on autonomic nervous system working in fetus from active mothers during gestation.

Modulation of Sarco/Endoplasmic Reticulum Ca2+-ATPase 2 (SERCA2) function by acetylation following the treatment with histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA)

Background: Acetylation and deacetylation at specific lysine (K) residues is mediated by histone acetylases (HATs) and deacetylases (HDACs), respectively. HATs and HDACs act on both histone and non-histone proteins, regulating various processes, including cardiac impulse propagation. Aim of the present work was to establish whether the function of the Ca2+ ATPase SERCA2, one of the major players in Ca2+ reuptake during excitation-contraction coupling in cardiac myocytes (CMs), could be modulated by direct K acetylation. Materials and methods: HL-1 atrial mouse cells (donated by Prof. Claycomb), zebrafish and Streptozotocin-induced diabetic rat CMs were treated with the pan-inhibitor of class I and II HDACs suberanilohydroxamic acid (SAHA) for 1.5 hour. Evaluation of SERCA2 acetylation was analyzed by co-immunoprecipitation. SERCA2 activity was measured on microsomes by pyruvate/NADH coupled reaction assay. SERCA2 mutants were obtained after cloning wild-type and mutated sequences into the pCDNA3 vector and transfected into HEK cells. Ca2+ transients in CMs (loading with Fluo3-AM, field stimulation, 0.5 Hz) and in transfected HEK cells (loading with FLUO-4, caffeine pulse) were recorded. Results: Co-Immunoprecipitation experiments performed on HL-1 cells demonstrated a significant increase in the acetylation of SERCA2 after SAHA-treatment (2.5 µM, n=3). This was associated with an increase in SERCA2 activity in microsomes obtained from HL-1 cells, after SAHA exposure (n=5). Accordingly, SAHA-treatment significantly shortened the Ca2+ reuptake time of adult zebrafish CMs. Further, SAHA 2.5 nM restored to control values the recovery time of Ca2+ transients decay in diabetic rat CMs. HDAC inhibition also improved contraction parameters, such as fraction of shortening, and increased pump activity in microsomes isolated from diabetic CMs (n=4). Notably, the K464, identified by bioinformatic tools as the most probable acetylation site on human SERCA2a, was mutated into Glutamine (Q) or Arginine (R) mimicking acetylation and deacetylation respectively. Measurements of Ca2+ transients in HEK cells revealed that the substitution of K464 with R significantly delayed the transient recovery time, thus indicating that deacetylation has a negative impact on SERCA2 function. Conclusions: Our results indicate that SERCA2 function can be improved by pro-acetylation interventions and that this mechanism of regulation is conserved among species. Therefore, the present work provides the basis to open the search for novel pharmacological tools able to specifically improve SERCA2 activity in diseases where its expression and/or function is impaired, such as diabetic cardiomyopathy.

Otimização não linear aplicada à operação de sistemas com múltiplos reservatórios para abastecimento de água.

O presente estudo considera a aplicação do modelo SISAGUA de simulação matemática e de otimização para a operação de sistemas de reservatórios integrados em sistemas complexos para o abastecimento de água. O SISAGUA utiliza a programação não linear inteira mista (PNLIM) com os objetivos de evitar ou minimizar racionamentos, equilibrar a distribuição dos armazenamentos em sistemas com múltiplos reservatórios e minimizar os custos de operação. A metodologia de otimização foi aplicada para o sistema produtor de água da Região Metropolitana de São Paulo (RMSP), que enfrenta a crise hídrica diante de um cenário de estiagem em 2013-2015, o pior na série histórica dos últimos 85 anos. Trata-se de uma região com 20,4 milhões de habitantes. O sistema é formado por oito sistemas produtores parcialmente integrados e operados pela Sabesp (Companhia de Saneamento do Estado de São Paulo). A RMSP é uma região com alta densidade demográfica, localizada na Bacia Hidrográfica do Alto Tietê e caracterizada pela baixa disponibilidade hídrica per capita. Foi abordada a possibilidade de considerar a evaporação durante as simulações, e a aplicação de uma regra de racionamento contínua nos reservatórios, que transforma a formulação do problema em programação não linear (PNL). A evaporação se mostrou pouco representativa em relação a vazão de atendimento à demanda, com cerca de 1% da vazão. Se por um lado uma vazão desta magnitude pode contribuir em um cenário crítico, por outro essa ordem de grandeza pode ser comparada às incertezas de medições ou previsões de afluências. O teste de sensibilidade das diferentes taxas de racionamento em função do volume armazenado permite analisar o tempo de resposta de cada sistema. A variação do tempo de recuperação, porém, não se mostrou muito significativo.

A randomised controlled trial investigating the effect of lutein and antioxidant dietary supplementation on visual function in healthy eyes

Background & aims It has been suggested that retinal lutein may improve visual acuity for images that are illuminated by white light. Our aim was to determine the effect of a lutein and antioxidant dietary supplement on visual function. Methods A prospective, 9- and 18-month, double-masked randomised controlled trial. For the 9-month trial, 46 healthy participants were randomised (using a random number generator) to placebo (n=25) or active (n=21) groups. Twenty-nine of these subjects went on to complete 18 months of supplementation, 15 from the placebo group, and 14 from the active group. The active group supplemented daily with 6mg lutein combined with vitamins and minerals. Outcome measures were distance and near visual acuity, contrast sensitivity, and photostress recovery time. The study had 80% power at the 5% significance level for each outcome measure. Data were collected at baseline, 9, and 18 months. Results There were no statistically significant differences between groups for any of the outcome measures over 9 or 18 months. Conclusion There was no evidence of effect of 9 or 18 months of daily supplementation with a lutein-based nutritional supplement on visual function in this group of people with healthy eyes. ISRCTN78467674.

The effect of nutritional supplementation on visual function

The aim of this research was to determine the effect of a lutein-based nutritional supplemented on measures of visual function in normal and ARMD-affected eyes. Thirty participants were recruited to the ARMD cohort (aged between 55 and 82 years, mean ± SD: 69.2 ± 7.8) and 46 were recruited into the normal cohort (aged between 22 and 73 years, mean ± SD: 50.0 ± 15.9). Outcome measures were distance (DVA) and near (NVA) visual acuity, contrast sensitivity (CS), photostress recovery time measured with the Eger Macular Stressometer (EMS), central visual function assessed with the Macular Mapping test (MMT), and fundus photography. Reliability studies were carried out for the EMS and the MMT. A change of 14 s is required to indicate a clinically significant change in EMS time, and a change of 14 MMT points is required to indicate a clinically significant change in MMT score. Sample sizes were sufficient for the trial to have 80% power to detect a significant clinical effect at the 5% significance level for all outcome measures in the normal cohort, and for CS in the ARMD cohort. The study demonstrated that a nutritional supplement containing 6mg lutein, 750 mg vitamin A, 250 mg vitamin C, 34 mg vitamin E, 10 mg zinc, and 0.5 mg copper had no effect on the outcome measures over nine or 18 months in normal or ARMD affected participants. The finding that nine months of antioxidant supplementation, in this case, has no significant effect on CS in ARMD-affected participants adds to the literature, and contrasts with previous RCTs, the AREDS and the LAST. This project has added to the debate about the use of nutritional supplementation prior to the onset of ARMD.

Discriminating contact in lumen with a moving flexible digit using fibre Bragg grating sensing elements

Minimal access procedures in surgery offer benefits of reduced patient recovery time and less pain, yet for the surgeon the task is more complex, as both tactile and visual perception of the working site is reduced. In this paper, experimental evidence of the performance of a novel sensing system embedded in an actuated flexible digit element is presented. The digit represents a steerable tip element of devices such as endoscopes and laparoscopes. This solution is able to discriminate types of contact and tissue interaction, and to feed back this information with the shape of the flexible digit. As an alternative to this information, force level, force distribution, and other quantifiable descriptors can also be evaluated. These can be used to aid perception in processes such as navigation and investigation of tissues through palpation. The solution is pragmatic, and by virtue of its efficient mechanical construction and a polymer construction, it offers opportunities for a disposable element with suitability for magnetic resonance imaging (MRI) and other scanning environments. By using only four photonics sensing elements, full perception of tissue contact and the shape of the actuated digit can be described in the feedback of this information. The distributive sensory method applied to the sensory signals relies on the coupled values of the sensory data transients of the four deployed sensing elements to discriminate tissue interaction directly in near real time.

Wideband-tuneable, nanotube mode-locked, fibre laser

Ultrashort-pulse lasers with spectral tuning capability have widespread applications in fields such as spectroscopy, biomedical research and telecommunications1–3. Mode-locked fibre lasers are convenient and powerful sources of ultrashort pulses4, and the inclusion of a broadband saturable absorber as a passive optical switch inside the laser cavity may offer tuneability over a range of wavelengths5. Semiconductor saturable absorber mirrors are widely used in fibre lasers4–6, but their operating range is typically limited to a few tens of nanometres7,8, and their fabrication can be challenging in the 1.3–1.5 mm wavelength region used for optical communications9,10. Single-walled carbon nanotubes are excellent saturable absorbers because of their subpicosecond recovery time, low saturation intensity, polarization insensitivity, and mechanical and environmental robustness11–16. Here, we engineer a nanotube–polycarbonate film with a wide bandwidth (>300 nm) around 1.55 mm, and then use it to demonstrate a 2.4 ps Er31-doped fibre laser that is tuneable from 1,518 to 1,558 nm. In principle, different diameters and chiralities of nanotubes could be combined to enable compact, mode-locked fibre lasers that are tuneable over a much broader range of wavelengths than other systems.

Discriminating contact in lumen with a moving flexible digit using fibre Bragg grating sensing elements

Minimal access procedures in surgery offer benefits of reduced patient recovery time and less pain, yet for the surgeon the task is more complex, as both tactile and visual perception of the working site is reduced. In this paper, experimental evidence of the performance of a novel sensing system embedded in an actuated flexible digit element is presented. The digit represents a steerable tip element of devices such as endoscopes and laparoscopes. This solution is able to discriminate types of contact and tissue interaction, and to feed back this information with the shape of the flexible digit. As an alternative to this information, force level, force distribution, and other quantifiable descriptors can also be evaluated. These can be used to aid perception in processes such as navigation and investigation of tissues through palpation. The solution is pragmatic, and by virtue of its efficient mechanical construction and a polymer construction, it offers opportunities for a disposable element with suitability for magnetic resonance imaging (MRI) and other scanning environments. By using only four photonics sensing elements, full perception of tissue contact and the shape of the actuated digit can be described in the feedback of this information. The distributive sensory method applied to the sensory signals relies on the coupled values of the sensory data transients of the four deployed sensing elements to discriminate tissue interaction directly in near real time.

Disturbance regime and limits on benefits of refuge use for fishes in a fluctuating hydroscape

Refuge habitats increase survival rate and recovery time of populations experiencing environmental disturbance, but limits on the ability of refuges to buffer communities are poorly understood. We hypothesized that importance of refuges in preventing population declines and alteration in community structure has a non-linear relationship with severity of disturbance. In the Florida Everglades, alligator ponds are used as refuge habitat by fishes during seasonal drying of marsh habitats. Using an 11-year record of hydrological conditions and fish abundance in 10 marshes and 34 alligator ponds from two regions of the Everglades, we sought to characterize patterns of refuge use and temporal dynamics of fish abundance and community structure across changing intensity, duration, and frequency of drought disturbance. Abundance in alligator ponds was positively related to refuge size, distance from alternative refugia (e.g. canals), and abundance in surrounding marsh prior to hydrologic disturbance. Variables negatively related to abundance in alligator ponds included water level in surrounding marsh and abundance of disturbance-tolerant species. Refuge community structure did not differ between regions because the same subset of species in both regions used alligator ponds during droughts. When time between disturbances was short, fish abundance declined in marshes, and in the region with the most spatially extensive pattern of disturbance, community structure was altered in both marshes and alligator ponds because of an increased proportion of species more resistant to disturbance. These changes in community structure were associated with increases in both duration and frequency of hydrologic disturbance. Use of refuge habitat had a modal relationship with severity of disturbance regime. Spatial patterns of response suggest that decline in refuge use was because of decreased effectiveness of refuge habitat in reducing mortality and providing sufficient time for recovery for fish communities experiencing reduced time between disturbance events.

Modelling of an efficient dynamic smart solar photovoltaic power grid system

A smart solar photovoltaic grid system is an advent of innovation coherence of information and communications technology (ICT) with power systems control engineering via the internet [1]. This thesis designs and demonstrates a smart solar photovoltaic grid system that is selfhealing, environmental and consumer friendly, but also with the ability to accommodate other renewable sources of energy generation seamlessly, creating a healthy competitive energy industry and optimising energy assets efficiency. This thesis also presents the modelling of an efficient dynamic smart solar photovoltaic power grid system by exploring the maximum power point tracking efficiency, optimisation of the smart solar photovoltaic array through modelling and simulation to improve the quality of design for the solar photovoltaic module. In contrast, over the past decade quite promising results have been published in literature, most of which have not addressed the basis of the research questions in this thesis. The Levenberg-Marquardt and sparse based algorithms have proven to be very effective tools in helping to improve the quality of design for solar photovoltaic modules, minimising the possible relative errors in this thesis. Guided by theoretical and analytical reviews in literature, this research has carefully chosen the MatLab/Simulink software toolbox for modelling and simulation experiments performed on the static smart solar grid system. The auto-correlation coefficient results obtained from the modelling experiments give an accuracy of 99% with negligible mean square error (MSE), root mean square error (RMSE) and standard deviation. This thesis further explores the design and implementation of a robust real-time online solar photovoltaic monitoring system, establishing a comparative study of two solar photovoltaic tracking systems which provide remote access to the harvested energy data. This research made a landmark innovation in designing and implementing a unique approach for online remote access solar photovoltaic monitoring systems providing updated information of the energy produced by the solar photovoltaic module at the site location. In addressing the challenge of online solar photovoltaic monitoring systems, Darfon online data logger device has been systematically integrated into the design for a comparative study of the two solar photovoltaic tracking systems examined in this thesis. The site location for the comparative study of the solar photovoltaic tracking systems is at the National Kaohsiung University of Applied Sciences, Taiwan, R.O.C. The overall comparative energy output efficiency of the azimuthal-altitude dual-axis over the 450 stationary solar photovoltaic monitoring system as observed at the research location site is about 72% based on the total energy produced, estimated money saved and the amount of CO2 reduction achieved. Similarly, in comparing the total amount of energy produced by the two solar photovoltaic tracking systems, the overall daily generated energy for the month of July shows the effectiveness of the azimuthal-altitude tracking systems over the 450 stationary solar photovoltaic system. It was found that the azimuthal-altitude dual-axis tracking systems were about 68.43% efficient compared to the 450 stationary solar photovoltaic systems. Lastly, the overall comparative hourly energy efficiency of the azimuthal-altitude dual-axis over the 450 stationary solar photovoltaic energy system was found to be 74.2% efficient. Results from this research are quite promising and significant in satisfying the purpose of the research objectives and questions posed in the thesis. The new algorithms introduced in this research and the statistical measures applied to the modelling and simulation of a smart static solar photovoltaic grid system performance outperformed other previous works in reviewed literature. Based on this new implementation design of the online data logging systems for solar photovoltaic monitoring, it is possible for the first time to have online on-site information of the energy produced remotely, fault identification and rectification, maintenance and recovery time deployed as fast as possible. The results presented in this research as Internet of things (IoT) on smart solar grid systems are likely to offer real-life experiences especially both to the existing body of knowledge and the future solar photovoltaic energy industry irrespective of the study site location for the comparative solar photovoltaic tracking systems. While the thesis has contributed to the smart solar photovoltaic grid system, it has also highlighted areas of further research and the need to investigate more on improving the choice and quality design for solar photovoltaic modules. Finally, it has also made recommendations for further research in the minimization of the absolute or relative errors in the quality and design of the smart static solar photovoltaic module.