Vegetación arbórea del Pedregal de Las Lajas, Refugio de Vida Silvestre Complejo San Marcelino, Sonsonate, El Salvador

En el Pedregal de Las Lajas, Refugio de Vida Silvestre Complejo San Marcelino, municipio de Izalco, Sonsonate, a 50 km de San Salvador, se desarrolló un estudio cualitativo y cuantitativo de vegetación arbórea se aplicó el método del cuadrado, utilizando 12 franjas longitudinales de 10 x 50 m (6000 m2); reportando 24 familias, 2 sub familias, 31 géneros y 38 especies distribuidas en 478 individuos muestreados. Las especies con mayor índice de valor de importancia (i.v.i.) fueron: pseudobombax ellipticum (130), plumería acutifolia (54), lysiloma divaricatum (45), cochlospermun vitifolium (32), urera baccífera (27) y euphatorium morifolium (26); especies que caracterizan comunidades de selva baja caducifolia. Así mismo se determinó los promedios de altura, reportándose a leucaena shannonii, clethra lanata y heliocarpus glanduliferus con los mayores promedios de altura y a euphatorium morifolium con el promedio de altura más baja. Además, se presenta una breve descripción botánica de las especies arbóreas reportada

Inertial behavior of offshore devices

Peer Reviewe

Síntesis y caracterización de polímeros de ciclodextrina. Aplicación a la liberación de fármacos

Cyclodextrins (CD) are cyclic oligosaccharides which have been widely employed for pharmaceutical applications. CD based hydrogels have been synthesized by the crosslinking reaction with epichlorohydrin using αCD, ßCD, γCD, and 50:50 mixtures of α/ßCD and ß/γCD, at different synthesis temperatures. These gels have been characterized by measuring their swelling capacity, mechanical behavior, thermal properties and pore size distribution. The hydrogels synthesized at higher temperatures present a higher swelling capacity, due to the self-polymerization of epichlorohydrin, yielding a more expanded reticular structure with pores of higher diameter. Mechanical assays show that a lower synthesis temperature leads to stronger and harder polymers, according with a lower swelling capacity. Polymers containing different CD types and synthesized at the same temperature present similar reticular structures. In order to investigate the sorption capacity of these hydrogels toward different solutes, five model molecules have been selected: phenol, 3-nitrophenol, 4-nitrophenol, 1-naphthol, and the antiinflamatory drug diflunisal. The amounts sorbed have been related to the different affinities of CDs to the solutes. Drug delivery of two antiinflammatory (naproxen and nabumetone) and two antifungal drugs (naftifine and terbinafine) from ßCD polymer discs has been investigated. Drug release kinetics were carried out at physiological conditions of pH and temperature, and kinetic and diffusion constants were calculated. The drug release followed a simple Fickian diffusion mechanism for all the model drugs. Also, diffusion coefficients were calculated according to the simplified Higuchi model. Naproxen was also used to perform release assays from polymers containing different CDs. The βCD polymer showed the highest amount of drug loaded and the lowest one corresponds to the polymer containing αCD, in agreement with the affinities for naproxen of the corresponding cyclodextrins. It can be inferred that a simple Fickian diffusion mechanism occurs, except for the mixed polymers at pH 1.2 (anomalous transport) and in the case αCDP at pH 7.0 (burst phenomenon). Furthermore, the diffusion and relaxation contributions have been determined for the mixed polymers in order to achieve progress in the design of new polymer matrices according to the structure of the selected drugs

Modelling and Simulation of Moored Devices for Ocean Currents Energy Harnessing

The main objective of this paper is the presentation of modelling solutions off loating devices that can be used for harnessing energy from ocean currents. It has been structured into three main parts. First, the growing current interest in marine renewable energy in general, and in extracting energy from currents in particular, is presented, showing the large number of solutions that are emerging and some of the most significant types. GESMEY generator is presented in second section. It is based on a new concept that has been patented by the Universidad Politécnica de Madrid and which is currently being developed through a collaborative agreement with the SOERMAR Foundation. The main feature of this generator is that on operation is fully submerged, and no other facilities are required to move to floating state for maintenance, which greatly increases its performance. Third part of the article is devoted to present the modelling and simulation challenges that arise in the development of devices for harnessing the energy of marine currents, along with some solutions which have been adopted within the frame of the GESMEY Project, making particular emphasis on the dynamics of the generator and its contro

La autopsia clínica en el Hospital de Txagorritxu de Vitoria durante el bienio 1991-1992. Un índice básico de la calidad de la asistencia sanitaria en la provincia de Alava

Análisis retrospectivo de los diagnósticos clínicos y hallazgos autópsicos de pacientes fallecidos en el Hospital "Txagorritxu" de Vitoria desde el 1 de Enero de 1990 hasta el 31 de Diciembre de 1991. El objeto de este estudio fue analizar la precisión de los diagnósticos clínicos, respecto a la enfermedad fundamental y causa de muerte, en relación con los hallazgos en las 406 autopsias realizadas durante dos años consecutivos. A pesar de los grandes avances de la ciencia y la técnica médica, la autopsia continúa teniendo un papel importante en el control de calidad de la asistencia sanitaria. De ahí, que la realización de autopsias sea un índice de calidad en las estadísticas sanitarias.1990eko urtarrilaren 6tik abenduaren 31rako tartean Gasteizko Txagorritxu ospitalean hildakoen aurkitze autopsiko eta diagnostiko klinikoen atzeranzko analisia. Lan honen helburua diagnostiko klinikoen zehaztasuna aztertzea izan da. Xehetasun hau egiaztatzeko bi urte hauetan zehar eginiko 406 autopsien emaitzak, aldez aurretik diagnostikatutakoarekin konparatu dira. Zientzia eta medikuntza teknikaren aurrerapenak haundiak izan badira ere autopsiak osasun laguntzaren arloan oso garrantzitsua izaten jarraitzen du, autopsiak egite honek osasun estatistiken kalitatean ezbairik gabeko eragina du.Analyse rétrospective des diagnostiques cliniques et des découvertes après autopsies de patients décédés à l'Hôpital "Txagorritxu" de Vitoria depuis le 1er janvier 1990 jusqu'au 31 décembre 1991. Le but de cette étude était d'analyser la précision des diagnostiques cliniques, concernant la maladie essentielle et la cause de la mort, en rapport avec les découvertes faites au cours des 406 autopsies réalisées durant deux ans consécutivement. Malgré les progrès importants de la science et de la technique médicale, l'autopsie continue de jouer un rôle important dans le contrôle de qualité de l'assistance sanitaire. Il s'ensuit que la réalisation d'autopsies est un indice de qualité dans les statistiques sanitairesA retrospective analysis of clinical diagnoses and autopsy findings of patients deceased at "Txagorritxu" Hospital during 1st January 1990 and 31st December 1991. The aim of the study was to analyse the accuracy of mayor clinical diagnoses and causes of death was estimated from the analysis of clinical diagnoses and autopsy findings in 406 cases during two consecutive years. In spite of the great advances in clinical and technological knowledge, the autopsy continues playing a key role in the quality control of medical practice. There is a considerable need for the performance of autopsies for the sake of medical statistics

Concepción general e hipótesis de diseño en los almacenamientos de gases licuados.España

El presente trabajo trata de resumir el estado actual en relación con el diseño de depósitos de hormigón pretensado para el almacenamiento de gases licuados a temperaturas criogénicas, haciendo hincapié en las acciones extraordinarias que condicionan el diseño de este tipo de almacenamientos. El producto criogénico más comúnmente almacenado en forma líquida es el gas natural que se licúa a —165 ºC y que, por lo tanto, es el que establece unos mayores requisitos de seguridad en el diseño de estos depósitos. El sumario de trabajo que sigue puede distribuirse en los siguientes apartados: — Necesidad del almacenamiento criogénico. — Factor económico en su transporte y almacenaje. — Distintos tipos de almacenamiento. — Descripción general de un almacenamiento criogénico. — Elementos esenciales de un depósito. — Consideraciones mínimas de seguridad. — Factores fundamentales en las hipótesis de diseño. — Tipos de acciones a considerar. — Acciones extraordinarias de origen interno. — Acciones extraordinarias de origen externo

How ChatGPT performs in Oral Medicine: The case of oral potentially malignant disorders

S

Comparative Study of the Efficiency of Different Noble Metals Supported on Hydroxyapatite in the Catalytic Lean Methane Oxidation under Realistic Conditions

The combustion of lean methane was studied over palladium, rhodium, platinum, and ruthenium catalysts supported on hydroxyapatite (HAP). The samples were prepared by wetness impregnation and thoroughly characterized by BET, XRD, UV-Vis-NIR spectroscopy, H2-TPR, OSC, CO chemisorption, and TEM techniques. It was found that the Pd/HAP and Rh/HAP catalysts exhibited a higher activity compared with Pt/HAP and Ru/HAP samples. Thus, the degree of oxidation of the supported metal under the reaction mixture notably influenced its catalytic performance. Although Pd and Rh catalysts could be easily re-oxidized, the re-oxidation of Pt and Ru samples appeared to be a slow process, resulting in small amounts of metal oxide active sites. Feeding water and CO2 was found to have a negative effect, which was more pronounced in the presence of water, on the activity of Pd and Rh catalysts. However, the inhibiting effect of CO2 and H2O decreased by increasing the reaction temperature.This research was funded by Ministerio de Economía y Competitividad (CTQ2015-73219-JIN (AEI/FEDER/UE)), Spanish ministry of Science and Innovation (PID2019-107105RB-I00 AEI/FEDER, UE) and Basque Government (GIC IT-1297-19)

New steps in the development of the second generation TEC GESMEY

The paper shows the results of the new steps that have been done in the development of the tidal energy converter GESMEY. These are the design, construction and trials into the sea of a 1/10 scale prototype and also the construction with the same scale of the buoy BOSCEM, that anchors the device and lets it in the correct work position and depth, along the two directions of the flow that the daily tidal cycle have. Inside the paper is described the objectives and the methodology of the experimental trials that were ca rry out the last summer with the scale prototype. GESMEY is a new type of tidal energy converter (TEC) that has the capability to exploit currents in waters over forty meters by itself and it gets only using its internal ballast system the necessary equilibrium between hy drostatics and hydrodynamics forces to make the emersion and the immersion procedures without any other help. Finally the paper shows the description of the results obtained over the performance of the devices along the immersion, emersion and floating transport manoeuvres and afterwards the results, that were obtained along the generation power tests that were carried out, are shown

Oxidation of residual methane from VNG vehicles over Co3O4-based catalysts: Comparison among bulk, Al2O3-supported and Ce-doped catalysts

Cobalt oxide based catalysts with three different active phase configurations, namely bulk, alumina supported and cerium-doped Co3O4 samples were examined for the complete oxidation of methane under conditions similar to those found in the exhaust of VNG engines. The structural and redox properties of the resulting catalysts were determined by N2 adsorption-desorption, WDXRF, ICP-AES, X-Ray diffraction, temperature-programmed reactions, UV–vis-NIR DRS, XPS and Raman spectroscopy. Alumina-supported catalysts (10–40%wt. Co) were found to be less active, since the strong interactions between the alumina and the Co3O4 active phase were highly detrimental for the redox properties of these catalysts. On the other hand, doping with cerium (10%wt.) led to an increased inherent activity of the Co 3 O4 phase by distorting the spinel lattice, which resulted in improved structural and redox properties and enhanced mobility of the oxygen species within the spinel lattice. These catalysts were also stable over a prolonged period of time under both dry and humid conditions (150 h).Ministry of Economy and Competitiveness (CTQ2016-80253-R) // Basque Government (IT657-13