Tissue effect on RNA:DNA ratios of marine fish larvae

In some routine studies of larval condition based on RNA:DNA ratios, heads and/or guts are removed for further age and feeding analysis. Also, during capture larvae are often found with their eyes missing. In this work we analysed tissues effects (muscle, head, eye, gut and the whole larvae) on RNA:DNA ratios from different species (Sardina pilchardus, Engraulis encrasicolus, Atherina presbyter and Paralichthys orbignyanus) in different developmental stages and from different locations. For all species and development phases, it was shown that RNA :DNA ratios in the head were significantly lower than in muscle or gut. The comparison of RNA :DNA ratios of head with or without eyes did not show significant differences. In a comparison of results from muscle from two tail sections, RNA :DNA ratios were higher for the anterior section in Sardina pilchardus and Engraulis encrasicolus larvae. Caution is needed when RNA :DNA ratios are compared with other studies employing different dissection protocols. For the species studied we propose conversion factors to be applied to RNA:DNA ratio data when different body sections are analysed. We discuss the most appropriate tissues for assessing nutritional condition in fish larvae, based on trends in concentrations of nucleic acids and ratios during starvation experiments

Evidence of displacement of lanternfish larvae associated with surface water movement: Case studies from Southern Africa

The paper is based on larval distribution data from five lanternfish species outside the spawning grounds of the adult populations. Using hydrographic information collected with the larvae, the effect of surface currentson the observed patterns of distribution is discussed. In the South-East Atlantic, adjacent to the Benguela upwelling system, larvae of the pseudoceanic Lampanyctodes hectoris were found farther offshore (250 – 450 km) than usual. The general flow of the current is parallel to the coast, but upwelling filaments extend offshore. The size distributions of the L. hectoris larvae found, together with the rather low temperature at two of the oceanic stations sampled, indicate that they had been displaced by a filament. In the South-West Indian Ocean, the distribution of larvae of highly oceanic species of lanternfish over the shelf is related to onshore intrusions of the Agulhas Current. The size distributions of Hygophum hygomii and Scopelopsis multipunctatus indicate southward transport of larvae. The presence of larvae of Myctophum selenops and Benthosema pterotum, which have not been documented as adults in the region, indicates not only transport to the area, but also that spawning could be taking place closer to the area than previously reported

An Integro-Differential Equation of the Fractional Form: Cauchy Problem and Solution

Producción CientíficaWe solve the Cauchy problem defined by the fractional partial differential equation [∂tt − κD]u = 0, with D the pseudo-differential Riesz operator of first order, and certain initial conditions. The solution of the Cauchy problem resulting from the substitution of the Gaussian pulse u(x, 0) by the Dirac delta distribution ϕ(x) = μδ(x) is obtained as corollary.MINECO grant MTM2014-57129-C2-1-P

Evaluación del comportamiento de las fábricas de ladrillos de tejar y argamasa debido a la humedad que asciende por capilaridad

For a better understanding of the behaviour of old brick masonry in facing the rising damp problem, multiple tests were made in the laboratory: water absorption, moisture content, apparent porosity, temperature and thermal camera imaging on brick masonry and its components: brick and mortar. This has allowed us to determine which of the previous tests is the best in predicting the behaviour of a real wall. In addition, the tests have also helped in defining a process to evaluate the moisture content of walls in a buildings, which is important for heritage restoration projects.Para un mejor conocimiento del comportamiento de las fábricas antiguas de ladrillo frente a la ascensión capilar de agua, se han realizado en laboratorio ensayos de absorción de agua, de contenido de humedad, de porosidad aparente, de temperatura e imágenes con cámara termográfica sobre muros de fábrica y sus materiales componentes: ladrillo y argamasa. Ello ha permitido inferir cuál es el ensayo realizado a los ladrillos que mejor predice el comportamiento del muro real. También ha permitido definir un procedimiento para evaluar el contenido de humedad de fábricas existentes, importante para los proyectos de restauración del patrimonio construido

Aproximación analítica de consumo de combustible y comportamiento periódico para un vehículo que viaja a través de una serie de semáforos

In this paper, we present a piecewise smooth system, that describes the dynamics of a single vehicle moving through a street that has a sequence of lights that turn on and off with a specific frequency. The model presents three dynamic ways: accelerated, decelerated and zero state. Besides, we show the description of the mathematical model used to simulate the system. The simulation was developed under an event-based scheme and implemented in Matlab. To make the numerical analysis, we take as a parameter study the cycle traffic light, which provides benefits to vehicular traffic system due to its configuration is achieved implementing optimization strategies for the phenomenon of green wave and reduces the travel time as the vehicle minimizes the number of stops along the road. Also, the stability was studied for the periodic orbits one and two. Finally, we made an approximation of fuel consumption. We assume that this is proportional to the mechanical energy produced by the motor. From this point of view, it can be concluded that it is possible to apply modeling and simulation strategies based on dynamic systems to understand the complex behaviors associated with the travel of vehicles in a traffic controlled by traffic lights.En el siguiente artículo, se presenta un sistema suave por tramos que describe la dinámica de un vehículo que se mueve a través de una calle con semáforos que se encienden y apagan con una frecuencia específica. El modelo presenta tres comportamientos dinámicos: acelerado, desacelerado y detenido. Además, se muestra la descripción del modelo matemático utilizado para simular el sistema. La simulación se desarrolló bajo un esquema basado en eventos y se implementó en Matlab. Para realizar el análisis numérico, se toma como parámetro el ciclo de los semáforos, que mejora el sistema de tráfico vehicular debido a que con su configuración se logran implementar estrategias de optimización permitiendo que los vehículos se desplacen en ola verde y reduzcan el tiempo de viaje, minimizando así, el número de paradas a lo largo del camino y reduciendo el consumo de combustible debido a las paradas y aceleradas. Además, se estudió la estabilidad de las órbitas periódicas uno y dos que presenta el modelo de simulación, así como sus implicaciones dinámicas. Finalmente, se presenta una propuesta para calcular el consumo de combustible, asumiendo que es proporcional a la energía mecánica producida por el motor, resulta en una propuesta novedosa que permite a las secretarias de movilidad comprender los comportamientos de los vehículos en vías principales de las ciudades. Desde este punto de vista, se puede concluir que es posible aplicar estrategias de modelado y simulación basadas en sistemas dinámicos para comprender los comportamientos complejos asociados al desplazamiento de los vehículos en una via controlada por semáforos

Diel-depth distributions of fish larvae off the Balearic Islands (western Mediterranean) under two environmental scenarios

Final workshop IDEADOS: The wrapping up of the IDEADOS project, International Workshop on Environment, Ecosystems and Demersal Resources and fisheries, 14-16 November 2012, Palma de Mallorca, SpainPeer reviewe

Bounding the output error in a buck power converter using perturbation theory

We show the main results obtained when applying the average theory to Zero Average Dynamic control technique in a buck power converter with pulse-width modulation (PWM). In particular, we have obtained the bound values for output error and sliding surface. The PWM with centered and lateral pulse configurations were analyzed. The analytical results have confirmed the numerical and experimental results already obtained in previous publications. Moreover, through an important lemma, we have generalized the theory for any stable second-order system with relative degree 2, using properties related to transformations and stability of linear systems.Peer Reviewe

Uso del mini nutritional assesment como herramienta de cribaje nutricional en la población mayor de 65 años en el ámbito hospitalario; conveniencia y factibilidad

The high prevalence of malnutrition in the growing population of older adults makes malnutrition screening critical, especially in hospitalized elderly patients. The aim of our study was to evaluate the use of the MNA® Mini Nutritional Assessment in hospitalized older adults for rapid evaluation of nutritional risk. A prospective cohort study was made of 106 patients 65 years old or older admitted to an internal medicine ward of a tertiary-care teaching hospital to evaluate the use of the short form, or screening phase, of the MNA-SF. In the first 48 hours of admission, the full MNA questionnaire was administered and laboratory tests and a dermatologic evaluation were made. The MNA score showed that 77% of the patients were at risk of malnutrition or were frankly malnourished. Low blood levels of albumin, cholesterol and vitamins A and D showed a statistically significant association with malnutrition or risk of malnutrition. Separate evaluation of the MNA-SF showed that it was accurate, sensitive and had predictive value for the screening process. Routine use of the MNA-SF questionnaire by admission nurses to screen patients is recommended. Patients with MNA-SF scores of 11 or lower should be specifically assessed by the nutritional intervention teamEl envejecimiento de la población y la elevada prevalencia de desnutrición en este colectivo hacen que el cribaje de desnutrición sea fundamental, especialmente en ancianos ingresados. Realizamos un estudio prospectivo sobre una población de 106 pacientes mayores de 65 años, ingresados en plantas de Medicina Interna de un hospital terciario, en el que se ha seguido la aplicación sistemática de Minimal Nutritional Assessment (MNA) en las primeras 48 horas de ingreso, así como una evaluación hematológica y dermatológica. Hemos detectado situación nutricional de riesgo (RM) o malnutrición (MN) en el 77% de los casos. Los marcadores biológicos que resultaron asociados estadísticamente a la MN o RM fueron la hipoalbuminemia, hipocolesterolemia, así como la hipovitaminosis A y D. Proponemos el empleo rutinario de la fase de cribaje del MNA por la enfermera de hospitalización, y la valoración específica por equipo especializado (Unidad de Nutrición) en caso de puntuación igual o inferior a 1