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Introducción: La leptospirosis es una enfermedad zoonótica causada por Leptospira interrogans y es transmitida por contacto directo con secreciones animales o agua contaminada. Veterinarios y estudiantes de medicina veterinaria son población en riesgo de adquirir la infección.Objetivo: Determinar la seroprevalencia de infección por Leptospira interrogans entre estudiantes de una facultad de medicina veterinaria en Bogotá, Colombia.Métodos: Se procesaron 445 sueros por ELISA, de los cuales 42 muestras se analizaron mediante microaglutinación (MAT).Resultados: La seroprevalencia a Leptospira por ELISA IgM fue del 7,9 % (35de 445). De ellos 34 sueros fueron positivos por MAT al menos para un serovar.Conclusión: Este estudio confirma la utilidad del diagnóstico serológico en individuos con riesgo ocupacional para adquirir la leptospirosis y resalta la importancia del uso de barreras de protección para todas las poblaciones que tienen contacto regular con animales, incluidos los estudiantes de medicina veterinaria.Introduction: Leptospirosis is a zoonotic disease caused by Leptospira interrogans and is transmitted by direct contact with animal secretions or contaminated water. Veterinary and veterinary students are population at risk of infection.Objective: To determine the seroprevalence of Leptospira interrogans infection among students in a School of Veterinary Medicine in Bogotá, Colombia. Methods: We processed 445 sera by ELISA test; then we analyzed 42 samples by microagglutination (MAT).Results: Leptospira seroprevalence by ELISA IgM was 7.9% (35 of 445). 34 sera were positive by MAT at least for one serovar.Conclusion: This study confirms the usefulness of serological diagnosis in individuals with occupational risk for Leptospirosis and stand out the importance of using protective barriers by all populations who have regular animal contact including veterinary students

Studying the Hall-Petch effect regarding sub-micrometer steel (0.6% C)

Este trabajo describe la obtención y caracterización mecánica de una aleación de acero 0,6% C con estructura de tamaño de grano inferior a 1 μm. El proceso para la obtención de piezas masivas se inicia sometiendo el polvo a severa deformación plástica en un molino planetario de bolas y a continuación se realiza la consolidación a alta presión y temperaturas entre 350 y 500 °C. El estudio de la evolución del tamaño de grano muestra que los consolidados sin tratamiento térmico posterior conservan su estructura en el rango nanométrico. En muestras con tratamiento térmico se observa un crecimiento controlado debido a los numerosos puntos de nucleación y la presencia de precipitados de cementita. Los resultados de dureza y tamaño de grano obtenidos cumplen la relación de Hall -Petch. Finalmente se analiza la influencia de las técnicas de obtención y de caracterización mecánica empleadas en este trabajo frente a diferentes fuentes bibliográficas.Postprint (published version

Caracterización de la variabilidad intra-racial en los parámetros productivos de añojos cebados en el sur de España

publishedTomo I . Sección: Sistemas Ganaderos-Economía y Gestión. Sesión: Vacuno carne II. Ponencia nº

Morphology of Platinum Electrodeposits in the Three-Dimensional Sublayer to Full Layer Range Produced under Different Potential Modulations on Highly Oriented Pyrolytic Graphite

The topography of platinum electrodes produced by electrodeposition (19 to 200 mC cm-2) on highly oriented pyrolytic graphite (HOPG) under different potential modulations was investigated by atomic force microscopy, scanning tunneling microscopy, and H-atom electrosorption voltammetry. To modulate electrodeposition, (i) triangular potential cycling at 0.1 V s-1, (ii) a linear cathodic potential at 0.1 V s-1 and anodic potential step cycling, and (iii) square wave potential cycling at 5000 Hz were utilized. AFM and STM imaging showed that at lower platinum loading the HOPG surface was partially covered by a 3D sublayer of platinum. Electrodes produced by procedure (i) were made of faceted platinum aggregates of about 200 nm and nanoclusters in the range of 5−20 nm; those that resulted from procedure (ii) consisted of anisotropic aggregates of nanoclusters arranged as quasi-parallel domains. These electrodes from (i) and (ii) behaved as fractal objects. The electrodes resulting from procedure (iii) exhibited a flat surface that behaved as a Euclidean object. For all WEs, as the platinum loading was increased the HOPG surface was fully covered by a thin 3D layer of platinum aggregates produced by electrodeposition and coalescence phenomena. Large platinum loading led to electrodes with fractal geometry. Statistical parameters (root-mean-square height, skewedness, kurtosis, anisotropy, Abbot curve, number of protrusions and valleys, and fractal dimension) were obtained from the analysis of AFM and STM imaging data. Platinum electrodeposition coupled to either H-adatom formation for procedures (i) and (ii) or phonon dispersion for (iii) was involved in the surface atom rearrangements related to electrofaceting. The H-adatom electrosorption voltammetry data were used to evaluate the real electrode surface area via the voltammetric charge and to advance a tentative explanation of the contribution of the different crystallographic facets to the global electrochemical process dominated by weak H−Pt adsorption interactions.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicada

On the Role of Perception: Understanding Stakeholders’ Collaboration in Natural Resources Management through the Evolutionary Theory of Innovation

Natural resources management deals with highly complex socioecological systems. This complexity raises a conundrum, since wide-ranging knowledge from different sources and types is needed, but at the same time none of these types of knowledge is able by itself to provide the basis for a viable productive system, and mismatches between the two of them are common. Therefore, a growing body of literature has examined the integration of different types of knowledge in fisheries management. In this paper, we aim to contribute to this ongoing debate by integrating the evolutionary theory of innovation—and specifically the concept of proximity—and the theory of perception. We set up a theoretical framework that is able to explain not only why the different types of knowledge differ, but also why they should differ and why this divergence is useful to develop fisheries management. This framework is illustrated through a well-known complex scenario, as was the implementation of the Landing Obligation (LO) in Europe. We conclude that diversity (distance) between types of knowledge is essential for interactive learning, innovation, the incorporation of new ideas or to avoid lock-in, etc. At the same time, cognitive, institutional, geographical, etc. proximity is needed for effective communication, participation and dialoguePostprin

¿Se está llevando a cabo un proceso de diferenciación en el mercado del aceite de oliva virgen extra? Un enfoque hedónico

The differentiation process by quality attributes continues to be an ongoing issue in the Spanish olive oil market. In addition, there is a significant percentage of uninformed consumers with erroneous and confusing ideas concerning this product of daily use. By estimating a hedonic price function using multiple regression analysis, this paper examines the price structure of extra virgin olive oil (EVOO) as well as the contribution of its attributes to the consumers’ utility function in comparison with other olive oils. The price and attributes have been collected from the labelling of the products at the main supermarkets in two olive oil-producing cities of southern Spain. The results show that the EVOO price is higher in products whose labels clearly indicate either the acidity or the olive variety, and bear the “Certified Quality” of the Andalusian logo. Nonetheless, several key attributes for a differentiation of quality were no significant such as flavor and PDO. The evaluation of these attributes implies the emergence of an incipient differentiation process. Furthermore, brands have an impact on the price of EVOO but it depends on whether they are private or manufacturer’s brands. This study provides insight into the Andalusian EVOO market as well as guidance for marketing strategies.La diferenciación entre calidades de aceite de oliva es una tarea aún pendiente del sector oleícola, que se enfrenta a una gran cantidad de consumidores desinformados, que tienen ideas confusas y erróneas sobre un alimento de uso cotidiano. A través de la estimación de la función de precios hedónicos, este trabajo analiza la estructura del precio del aceite de oliva virgen extra (AOVE) así como los atributos que le añaden o le restan valor, con el objetivo de identificar en qué medida el mercado está poniendo en valor determinados atributos que diferencian al AOVE de otros aceites de oliva. La información necesaria sobre precios y atributos ha sido obtenida a partir del etiquetado de los productos presentes en las principales cadenas de supermercados de dos ciudades productoras de aceite de oliva de Andalucía. Los principales resultados muestran que el precio de un AOVE será mayor si en su etiqueta aparece la acidez o la variedad de aceituna, y si tiene el sello de “Calidad Certificada” de Andalucía, atributos que en efecto suponen la emergencia de un proceso, aún incipiente, de diferenciación del AOVE. Las marcas comerciales también tienen un importante impacto sobre el AOVE, pero éste depende de si se trata de una marca de distribuidor o de una empresa líder del sector. Esta información es interesante para conocer el mercado andaluz actual y puede servir a los productores para orientar posibles actuaciones dentro del marketing mix

Synthesis and Electrocatalytic Properties of H2SO4-Induced (100) Pt Nanoparticles Prepared in Water-in-Oil Microemulsion

The increasing number of applications for shape-controlled metal nanoparticles (NPs) has led to the need for easy, cheap, and scalable methodologies. We report the synthesis of (100) preferentially oriented Pt NPs, with a particle size of 9 nm, by using a water-in-oil microemulsion method. The specific surface structure of the NPs is induced by the presence of H2SO4 in the water phase of the microemulsion. Interestingly, the results reported herein show how increasing amounts of H2SO4 lead to the formation of Pt NPs containing a larger amount of (100) sites on their surface. This preferential surface orientation is confirmed electrochemically by using the so-called hydrogen adsorption/desorption process. In addition, transmission electron microscopy measurements confirm the presence of cubic-like Pt NPs. Finally, the electrocatalytic properties of the Pt NPs are evaluated towards ammonia and CO electro-oxidations, which are (100) structure-sensitive reactions.This work has been financially supported by the MCINN-FEDER (Spain) (project CTQ 2010-16271), Generalitat Valenciana (project PROMETEO/2009/045) and in part by NASA-URC Grant No. NNX10AQ17A and NSF-NSEC Center for Hierarchical Manufactur-ing Grant No. CHM-CMMI-0531171. R. M-R is grateful to the Becas Iberoamérica, Santander Universidades-España 2012 and PR-LSAMP Bridge to Doctorate Fellowship programs

COVID-19 pandemic on coronary artery and cerebrovascular diseases in Southern Spain: interrupted time series analysis

Objective: Healthcare systems have been put under intense pressure by the COVID-19 pandemic, although some studies have shown a decline in hospital admissions for cardiovascular and cerebrovascular diseases during the first and second wave of the pandemic. In addition, studies analyzing gender and procedural differences are scarce. The present study aimed to determine the impact of the pandemic on hospital admissions for acute myocardial infarction (AMI) and cerebrovascular disease (CVD) in Andalusia (Spain) and analyzed differences by gender and by percutaneous coronary interventions performed. Patients and methods: An interrupted time series analysis of AMI and CVD hospital admissions in Andalusia (Spain) was carried out to measure the impact of the COVID-19 outbreak. AMI and CVD cases admitted daily in public hospitals of Andalusia between January 2018 and December 2020 were included. Results: During the pandemic, significant reductions in AMI [-19%; 95% confidence interval (CI): (-29%, -9%), p<0.001] and CVD [-17%; 95% CI: (-26%, -9%); p<0.01] in daily hospital admissions were observed. Differences were also produced according to the diagnosis (ST-Elevation Myocardial Infarction, Non-ST-Elevation Myocardial Infarction, other AMI and stroke), with a greater reduction in females for AMI and in males for CVD. Although there were more percutaneous coronary interventions during the pandemic, no significant reductions were observed. Conclusions: A decline in AMI and CVD daily hospital admissions during the first and second wave of COVID-19 pandemic was noted. Gender differences were observed, but no clear impact was observed in percutaneous interventions

First record of the genus Leptodactylus (Anura: Leptodactylidae) in Cuba: Leptodactylus fragilis, a biological invasion?

The Neotropical genus Leptodactylus is currently represented by three species in the West Indies (Leptodactylus albilabris, Leptodactylus fallax and Leptodactylus validus). Based on morphological, acoustic and molecular evidence, we document the presence of a fourth species in the Caribbean region, Leptodactylus fragilis (Brocchi, 1877). The species was found at two localities in western Cuba, and molecular data suggest a northern South American origin, possibly Venezuela, for these populations. We discuss the potential invasive status of L. fragilis, based on its known distribution, relative abundance, behaviour and possible impacts on native species of Cuban amphibians