Variabilidad morfométrica en crustáceos de playas arenosas de la Isla Grande de Chiloé, sur de Chile

Indexación: Web of Science; Scielo.The macroinfauna of exposed sandy beaches along the Chilean coast is dominated by crustaceans, which show an across-shore zonation; the talitrid amphipod Orchestoidea tuberculata as the dominant taxon in the upper levels, the cirolanid isopod Excirolana hirsuticauda is dominant in the mid-intertidal, and the anomuran crab Emerita analoga is common in the low levels. This study analyses samples collected during the spring of 2001 and 7 morphological characters were measured on 30 adults of each species: body length, body height, body width, antennae and uropodal exopod lengths. The study sites were located near 42°S, an area where various beach types (i.e., reflective, intermediate and dissipative) occur along the northern coasts of the Chilean archipelagos. The morphometric variability of O. tuberculata, E. hirsuticauda and E. analoga was analyzed using cluster and principal component analysis. The results of this study showed that independently of beach type, individuals of O. tuberculata inhabiting proximal beaches showed greater similarity than individuals inhabiting beaches located distant from each other. Individuals of E. analoga inhabiting similar beach types showed greater similarity than individuals living in different beach types. These results are discussed in relation to across-shore zonation and the natural history of these species.La macroinfauna de playas arenosas expuestas en la costa chilena está dominada por crustáceos, los cuales muestran una zonación transversal; el anfípodo talítrido Orchestoidea tuberculata es el taxón dominante en los niveles superiores, el isópodo cirolánido Excirolana hirsuticauda lo es en la parte media del intermareal y el anomuro Emerita analoga es dominante en los niveles bajos. Este estudio examinó la variabilidad morfométrica de estas 3 especies de crustáceos en relación a los tipos morfodinámicos de playas. Las muestras fueron recolectadas durante la primavera de 2001 y se examinaron 7 caracteres morfológicos medidos en 30 adultos de cada especie: longitud del cuerpo, alto del cuerpo, ancho de cuerpo, longitud de las antenas y longitud de los urópodos. Los sitios de estudio se localizaron cerca de los 42°S, un área donde los diferentes tipos de playa (i.e., reflectivo, intermedio y disipativo) se producen a lo largo de las costas septentrionales de los archipiélagos chilenos. La variabilidad morfométrica de O. tuberculata, E. hirsuticauda y E. analoga se analizó mediante análisis de cluster y de componentes principales. Los resultados de este estudio mostraron que, independientemente del tipo de playa, los individuos de O. tuberculata que habitan playas próximas presentan una mayor similitud que con aquellas que habitan playas lejanas. Los individuos de E. analoga que habitan en el mismo tipo de playa mostraron una mayor similitud que con aquellas que habitan en diferentes tipos de playas. Estos resultados se discuten en relación con la zonificación a través del intermareal y la historia natural de estas especies.http://ref.scielo.org/rcysp

Taxonomy and phylogeny of clinically important mucoralean fungi

Recientemente, varios estudios han comunicado la creciente incidencia de mucormicosis tanto en pacientes inmunosuprimidos como inmunocompetentes (Bitar et al., 2009; Roden et al., 2005; Saegeman et al., 2010). Algunas especies pertenecientes al orden Mucorales (subphylum Mucoromycotina) son considerados patógenos oportunistas, causando infecciones con una alta tasa de mortalidad. Interesante es el cambio epidemiológico observado tanto en Apophysomyces elegans, como en Saksenaea vasiformis, dos especies consideradas patógenos emergentes, con una gran relevancia clínica en los últimos años, debido a la infección en personas inmunocompetentes. Otro aspecto relevante es el hecho de que los Mucorales son resistentes a la mayoría de los antifúngicos disponibles en la actualidad. La anfotericina B es el único medicamento antimicótico que ha demostrado una potente actividad in vitro y una considerable eficacia in vivo. Sin embargo, la eficacia clínica sigue siendo limitada, con una alta tasa de mortalidad, sobre todo cuando las infecciones son causadas por agentes tales como Saksenaea vasiformis o Apophysomyces elegans. En la presente tesis, se analizó un amplio panel de aislamientos procedentes de muestras clínicas, principalmente de los Estados Unidos de América. Hemos sido capaces de demostrar la utilidad de las herramientas morfológicas en la identificación de los mucorales, obteniendo un 92% de correlación con las herramientas moleculares. Además, y en base a un enfoque polifásico, que incluyó el análisis de la morfología, la fisiología y las secuencias de diversos genes; siete nuevas especies de mucorales han sido descubiertas y descritas: Apophysomyces ossiformis; Apophysomyces trapeziformis; Apophysomyces variabilis; Mucor ellipsoideus; Mucor velutinosus; Saksenaea erythrospora, y Saksenaea oblongispora.Recently, several studies have reported the increasing incidence of mucormycosis in both immunocompromised and immunocompetent patients (Bitar et al., 2009; Roden et al., 2005; Saegeman et al., 2010). Some species belonging to the order Mucorales (subphylum Mucoromycotina) are considered opportunistic pathogens, causing infections with a high mortality rate. Interesting is the epidemiological change observed in both Apophysomyces elegans and Saksenaea vasiformis, two species considered emerging pathogens, with a high clinical relevance in recent years, due to the infection in immunocompetent people. Another relevant aspect is the fact that the Mucorales are resistant to most of the currently available antifungal drugs. Amphotericin B is the only antifungal drug to show potent in vitro activity and in vivo efficacy. Nevertheless, the clinical efficacy remains limited, with high mortality rate, especially when the infections are caused by either Saksenaea vasiformis or Apophysomyces elegans. In the present thesis, we analyzed a large panel of isolates from clinical samples, principally from of the United States of America. We have been able to demonstrate the useful of morphological tools in the identification of mucoralean fungi, obtaining a 92% of correlation with the molecular tools. Additionally, and based on a polyphasic taxonomy approach which included morphology, physiology and DNA sequence analyses, 7 new species of mucoralean fungi have been discovered and described: Apophysomyces ossiformis; Apophysomyces trapeziformis; Apophysomyces variabilis; Mucor ellipsoideus; Mucor velutinosus; Saksenaea erythrospora, and Saksenaea oblongispora

Sentiment analysis on twitter for the portuguese language

Dissertação para obtenção do Grau de Mestre em Engenharia InformáticaWith the growth and popularity of the internet and more specifically of social networks, users can more easily share their thoughts, insights and experiences with others. Messages shared via social networks provide useful information for several applications, such as monitoring specific targets for sentiment or comparing the public sentiment on several targets, avoiding the traditional marketing research method with the use of surveys to explicitly get the public opinion. To extract information from the large amounts of messages that are shared, it is best to use an automated program to process these messages. Sentiment analysis is an automated process to determine the sentiment expressed in natural language in text. Sentiment is a broad term, but here we are focussed in opinions and emotions that are expressed in text. Nowadays, out of the existing social network websites, Twitter is considered the best one for this kind of analysis. Twitter allows users to share their opinion on several topics and entities, by means of short messages. The messages may be malformed and contain spelling errors, therefore some treatment of the text may be necessary before the analysis, such as spell checks. To know what the message is focusing on it is necessary to find these entities on the text such as people, locations, organizations, products, etc. and then analyse the rest of the text and obtain what is said about that specific entity. With the analysis of several messages, we can have a general idea on what the public thinks regarding many different entities. It is our goal to extract as much information concerning different entities from tweets in the Portuguese language. Here it is shown different techniques that may be used as well as examples and results on state-of-the-art related work. Using a semantic approach, from these messages we were able to find and extract named entities and assigning sentiment values for each found entity, producing a complete tool competitive with existing solutions. The sentiment classification and assigning to entities is based on the grammatical construction of the message. These results are then used to be viewed by the user in real time or stored to be viewed latter. This analysis provides ways to view and compare the public sentiment regarding these entities, showing the favourite brands, companies and people, as well as showing the growth of the sentiment over time