Puertos francos : serie de artículos sobre esta cuestion publicados en El Noticioso, periódico de esta Capital

Colofó

Al público

Se trata de la contestación de Pedro Mariano Ramírez al proyecto de Manuel Ossuna Saviñón sobre el puerto franco en Santa Cruz y la división de Canarias en dos provinciasDatos de imp. tomados del colofó

Habitantes de Santa Cruz : Los sucesos de la noche del 31, habian terminado mi vida política ...

Se trata del manifiesto de Pedro M. Ramirez antes de embarcarse para Cádiz a exigencias de la Junta de La LagunaTexto firmado por Pedro M. RamirezTexto fechado a bordo del Místico Buen-mozo, en el Puerto de Santa Cruz 3 de agosto de 1843Hoja impresa por una sola car

Preferencias tróficas de Pterois volitans (Scorpaenidae) en el área costera de Holguín, Cuba

El pez león (Pterois volitans) es una especie arrecifal que ha invadido de una manera vertiginosa el Atlántico Occidental. Este estudio tuvo como objetivo caracterizar la dieta del pez león en la zona costera de Holguín, Cuba. Para ello, se realizaron ocho campañas de muestreo durante el período abril-noviembre de 2016 en seis sitios costeros, incluyendo arrecifes frontales, artificiales y bahías, ubicados entre los 14 y 35 m de profundidad. Se analizó un total de 250 ejemplares con tallas entre 8 y 33 cm de longitud estándar. A través del análisis de sus contenidos estomacales se identificaron 27 tipos de presa, las cuales se agruparon en las categorías tróficas de peces, crustáceos y moluscos. Los peces fueron el componente preferencial en la dieta del pez león en base a los métodos numérico, frecuencia de ocurrencia, gravimétrico e índice de importancia relativa. Dentro de las presas, las especies de peces Holocentrus rufus y Monocanthus tuckeri fueron las más representativas. La dieta del pez león en el área de estudio reflejó la disponibilidad de las presas en cada sitio, lo que sugiere que es un predador oportunista (Índice de Levin = 0.91). No se encontró diferencias estadísticas en relación a la similitud entre los sitios de muestreo a partir del aporte del peso de los diferentes componentes consumidos

Minimum Energy Storage Converters based on a Coupled Magnetic Structure: Design Methodology

This paper presents a design methodology for coupled inductor converters designed and operated under the principle of minimum energy storage. This minimum energy storage concept is applied to a coupled inductor converter along with a control strategy that aims to keep constant the sum of input voltages to the magnetic component for every instant of time. If the input voltage is kept constant, output voltage would be also constant for every instant of time and the energy storage in the converter would be minimized. The main advantage of this concept is that a very fast dynamic response can be achieved without operating at very high frequencies, thus maximizing efficiency in a wide load range. Instead of continuous voltage regulation, output voltage can be changed in discrete values, which could be a drawback in some applications. The proposed design methodology is applied in order to design a four-cell prototype and it is validated with an experimental prototyp

Core-less Multiphase Converter with Transformer Coupling

A coupled multiphase converter where the coupling among the phases is done using core-less planar transformers is presented in this paper. Operating principle of the transformer-coupled converter has been presented previously in the literature and in this paper this concept is applied to develop a core-less converter. Two prototypes operating at high frequency (4 MHz), with low profile (3 mm - 4 mm) and 60 W of output power, with two different core-less transformers are presented. Main advantages of applying this concept at high frequency are size reduction and operation with core-less transformers. This topology can be considered as a dc-dc transformer and applications for this topology can be `dc-dc transformers' for two-stage power supply systems and voltage scaling power supplies

Power analog to digital converter for voltage scaling applications

In order to optimize energy efficiency, some applications require adapting supply voltage according to the work load requirements. For example, in high performance digital systems and in RF systems, voltage scaling and modulation techniques have been adopted in order to achieve a more efficient processing of the energy. These techniques are based in rapidly adjusting the system supply voltage level. In order to achieve this, a topology which is capable of achieving very fast changes of the output voltage is needed. In this paper a PWM multiphase topology whose phases are coupled by using transformers is proposed to be used in an envelope elimination and restoration (EER) technique. The proposed topology can achieve very fast changes between discrete voltage steps so it can be considered as a power analog to digita

Role for physical fitness in the association between age and cognitive function in older adults: a mediation analysis of the SABE colombia study

Objectives. We investigated the association between physical fitness and cognitive status. Further, we examined whether physical fitness mediates the association between cognitive functioning and aging. Design. Cross-sectional study. Setting. Urban and rural Colombian older adults. Methods. 4416 participants from the SABE study were included in the current analysis. Physical fitness was assessed with the handgrip test and the usual gait speed test. Cognitive status was evaluated through the Folstein Mini-Mental State Examination. A parallel mediation path was used to test the possible mediator role of physical fitness between aging and cognitive functioning. Results. Older adults with lower handgrip strength (HGS) were more likely to have mild-cognitive status than older adults with healthy HGS (OR = 1.53, 95% CI = 1.15; 2.02). In addition, older adults with a slower gait speed were more likely to have mild cognitive impairment (OR = 2.05, 95% CI = 1.54; 2.78). Age had an inverse relationship with cognitive function (β = -0.110, 95% CI = -0.130; -0.100) and it was also inversely associated with HGS (β = -0.003, 95% CI = -0.005; -0.002) and gait speed (β = -0.010, 95% CI = -0.011; -0.009). The indirect effects, which indicate that the effect of age on cognitive function is transmitted through mediators, showed that both gait speed (β = -0.028, 95% CI = -0.036; -0.020) and HGS (β = -0.014, 95% CI = -0.024; -0.005) were independent mediators of the detrimental effect of aging on cognitive function. Conclusions. Physical fitness mediates the effects of aging on cognitive functioning. Our findings suggest that physical activity can be a key factor to prevent cognitive deterioration during aging process.The study was funded by the Ministry of Health and Social Protection of Colombia Colciencias contract No. 764 of 2013. Robinson Ramírez-Vélez training grant (ID420) as a postdoctoral research fellow with the Universidad Pública de Navarra (UPNA)