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Item Metadata only When Memes Become a Serious Business: Memetics as a Political Communication Strategy in the United States and Ecuador(202-10-01) Carrillo Andrade, Andrea del Carmen; López Paredes, Marco Vinicio; Andrea Carrillo, Andrade del CarmenThe media convergence model refers to a context in which the information is produced by every and anybody, without intermediates or filters. This offers new possibilities for citizens and politicians to interact and frame situations. One way to do so is by memetics. Memes have 3 main characteristics: (1) Diffuse at the micro level but shape the macro structure of society; (2) Use cultural items that people can potentially imitate; (3) Travel through competition and selection. When it comes to political memes, few research has been held. That is why the research question that arises is how memes allow prosumers to interact and opine about politicians? The present investigation based in multimodal analysis compares memes among United States and Ecuador when former Presidents were banned from social networks. It concludes that public discussion memes are the preferred ones for prosumers; they use cultural items to create situational jokes and make fun of politicians. These memes imitate instead of creating new messages, are restricted about the topics and generate polarized meanings.Item Open Access 
Detecçao rápida de Salmonella enteritidis em alimentos por ensaio imunoenzimatico Elisa(2003) Alcocer Negrete, Iliana del Rocío; Alcocer Negrete, Iliana Del RocíoTraditional cultural methods for the detection of Salmonella in foods is a labour-intensive and time-consuming, taking 4 to 5 days for the final results to be known. Therefore, simplified and rapid methods are required for both diagnosis of foodborne diseases and microbiological food quality control. The aim of this study was to develop an enzyme-linked immunosorbent assay (ELISA) for the detection of Salmonella Enteritidis in foods. The assay used a polyclonal detector antibody to flagelin raised in rabbit. The method sensitivity was of 10 cells/mL of pure culture. The horseradish peroxidase conjugate was stabel up to two months at 4°C and for this reason it should be used only during this period.Item Metadata only Diseño de un nucleo de un sistema operativo(2009) Calderón Serrano, Jorge AlfredoIntroducción; diseño de un núcleo du un sistema operativo; implementación de KMOS; talleres de implementación de rutinas; especificaciones técnicas hardware y software; multiprocesamiento; casos de estudio; laboratorios de as/400, Solaris, Linux, KMOS.Item Metadata only Would tropical climatic variations impact the genetic variability of triatomines: Rhodnius ecuadoriensis, principal vector of Chagas disease in Ecuador?(2009-09) Villacis Salazar, Anita Gabriela; Yumiseva Marín, Cesar Alberto; Villacis Salazar, Anita GabrielaRhodnius ecuadoriensis is one of the most important vector species of Chagas disease in Ecuador. This species is distributed in the Central coast region and in the south Andean region, and an incipient speciation process between these geographical populations was previously proposed. The current population genetics study only focused on the Central coast region and analyzed 96 sylvatic specimens of R. ecuadoriensis associated with Phytelephas aequatorialis palm trees. We used Cytb and 16S-rRNA sequences and a Cytb-16S-rRNA concatenated set to explore (i) the genetic variability, spatial structuring, and demographic history of R. ecuadoriensis, and to determine (ii) the relationship between the genetic and climatic variabilities. A particularly high genetic variability was observed without detectable general genetic structure; only some terminal genetic clusters were observed. We did not observe isolation by geographical distance (IBD), and it is likely that ancient expansion occurred, according to Fs index and mismatch distribution for Cytb-16S-rRNA concatenated sequences. Hierarchical clustering showed that the current locality origins of the bugs were grouped into four bioclimatic clusters. Genetic and bioclimatic distances were not correlated, but some genetic clusters were associated with bioclimatic ones. The results showed an ancient evolution of the species in the region with a possible old expansion. The absence of spatial genetic structure could be due to climatic conditions (possible selection of singular genotypes) and to passive transportation of palms tree materials where R. ecuadoriensis are living.Item Open Access Genetic differentiation within the Puccinia triticina popuation in South America and Comparison with the North American Population suggests common ancestry and intercontinental migration(2010) Ordoñez Maldonado, María Eugenia; Ordoñez, M.E.Leaf rust, caused by Puccinia triticina, is the most prevalent and widespread disease of wheat in South America. The objective of this study was to determine whether genetically differentiated groups of P. triticina are currently present in South America and to compare the South American population with the previously characterized population in North America. In total, 130 isolates of P. triticina from the wheat- growing regions of Argentina, Brazil, Chile, Peru, and Uruguay, mostly from the 1990s to 2008, were tested for virulence on 20 lines of wheat with single genes for leaf rust resistance and for molecular genotypes with 23 simple-sequence repeat (SSR) markers. After removal of isolates with identical virulence and SSR genotypes, 99 isolates were included for further analysis. Principal coordinate analysis plots indicated five different groups of isolates based on SSR genotypes that also differed for virulence to leaf rust resistance genes. All pairs of groups, except for one pair, were significantly differentiated for SSR genotypes according to RST statistics. All but two pairs of groups were significantly differentiated for virulence phenotype according to ΦPT statistics. Isolates in all five groups had high values of fixation index for SSR alleles and linkage dis- equilibrium was high across all isolates that indicated the clonal repro- duction of urediniospores. Only one of the five P. triticina groups from South America was differentiated for SSR genotypes from all of the six P. triticina groups from North America. The high degree of similarity for SSR genotype of isolates from both South America and North America suggested a common European origin of P. triticina that was introduced to both continents. The emergence of the same P. triticina virulence phenotypes with highly related SSR genotypes in the United States in 1996 and in Uruguay in 1999 indicated the likely intercontinental migra- tion of these genotypes from Mexico to both South America and North America.Item Open Access Using museum collection to detect pathogens(2010) Grijalva Cobo, Mario Javier; Pinto, Miguel.Item Open Access Ecological and genetic divergence between two lineages of Middle American túngara frogs Physalaemus (=Engystomops) pustulosus(2010) Ron Melo, Santiago Rafael; Pröhl, Heike.Uncovering how populations of a species differ genetically and ecologically is important for understanding evolutionary processes. Here we combine population genetic methods (microsatellites) with phylogenetic information (mtDNA) to define genetic population clusters of the wide-spread Neotropical túngara frog (Physalaemus pustulosus). We measure gene flow and migration within and between population clusters and compare genetic diversity between population clusters. By applying ecological niche modeling we determine whether the two most divergent genetic groups of the túngara frog (1) inhabit different habitats, and (2) are separated geographically by unsuitable habitat across a gap in the distribution. Most population structure is captured by dividing all sample localities into two allopatric genetic lineages. The Northern genetic lineage (NW Costa Rica) is genetically homogenous while the Southern lineage (SW Costa Rica and Panama) is sub-divided into three population clusters by both microsatellite and mtDNA analyses. Gene flow is higher within the Northern lineage than within the Southern lineage, perhaps due to increased landscape heterogeneity in the South. Niche modeling reveals differences in suitable habitat between the Northern and Southern lineages: the Northern lineage inhabits dry/pine-oak forests, while the Southern lineage is confined to tropical moist forests. Both lineages seem to have had little movement across the distribution gap, which persisted during the last glacial maximum. The lack of movement was more pronounced for the Southern lineage than for the Northern lineage. This study confirms the finding of previous studies that túngara frogs diverged into two allopatric genetic lineages north and south of the gap in the distribution in central Costa Rica several million years ago. The allopatric distribution is attributed to unsuitable habitat and probably other unknown ecological factors present across the distribution gap. Niche conservatism possibly contributes to preventing movements across the gap and gene flow between both groups. Genetic and ecological data indicate that there is the potential for ecological divergence in allopatry between lineages. In this context we discuss whether the Northern and Southern lineages should be recognized as separate species, and we conclude that further studies of pre- and post-zygotic isolation are needed for a final assessment. Identified population clusters should motivate future behavioral and ecological research regarding within-species biodiversity and speciation mechanisms.Item Open Access Estudio Computacional de Derivados de 5-Hidroximetilfurfural(2010) Meneses Olmedo, Lorena Maribel; Meneses, L.Los problemas ambientales asociados al uso de petróleo, han conseguido que la comunidad científica tome caminos alternativos como lo es la transformación de la biomasa en compuestos químicos básicos. El compuesto 5-hidroximetifurfural (HMF) es considerado un producto químico versátil de la biomasa, ya que puede ser utilizado para sintetizar gran variedad de compuestos que actualmente son derivados del petróleo. En este trabajo, se presenta un estudio computacional de los índices globales de electrofilia y nucleofilia del HMF y sus derivados para determinar los patrones de reactividad, mientras que los patrones de selectividad se analizaron mediante los índices locales de electrofilia y nucleofilia. El modelo teórico ha sido analizado comparando distintos métodos empleados para el cálculo de los índices globales de electrofilia y nucleofilia, resultando una buena correlación entre los modelos de electrofilia, más entre los modelos de nucleofilia su correlación es pobre.Item Open Access Comparison of Lim1 expression in embryos of frogs with different modes of reproduction(2010) Del Pino, Eugenia; Venegas-Ferrín, Michael.A polyclonal antibody was used to detect the expression of the homeodomain protein Lim1 (Lhx1) in embryos of Xenopus laevis, Engystomops randi, Colostethus machalilla and Gastrotheca riobamabae. These frogs belong to four separate families, and have differences in their modes of reproduction and developmental rates. The expression of Lim 1 in embryos of these frogs resembled the X. laevis expression pattern. Thus, the dorsal blastopore lip, axial mesoderm, pronephros and certain cells of the central nervous system were Lim1-postive in embryos of all frogs. There were, however, time differences; thus, in the mid-gastrula of the rapidly developing embryos of X. laevis and E. randi, the Lim1 protein was simultaneously detected in the prechordal plate (head organizer) and notochord (trunk organizer). In contrast, only the prechrodal plate was Lim1- positive during gastrulation in the slow developing embryos of C. machalilla. The notochord elongated and became Lim-1 positive after closure of the blastopore in C. machalilla and G. riobambae embryos. The prechordal plate of G. riobambae embryos could not be clearly detected, as the Lim 1-signal remained around the blastopore during gastrulation. These observations indicate that the timing of gene expression at the dorsal blastopore lip in embryos of slow developing frogs differs from that of X. laevis. Moreover, the comparison shows that the developmental processes of the head and trunk organizers are basically separable and become dissociated in embryos of the slow developing frog, C. machalilla.Item Open Access Microdistribution of Sylvatic Triatomine populations in Central-Coastal Ecuador(2010) Villacís Salazar, Anita Gabriela; Suarez-Dávalos, Victoria.Chagas disease is a serious public health problem in Ecuador, where nearly 230,000 individuals show Trypanosoma cruzi infection. Sylvatic T. cruzi transmission is a threat to current control strategies. This is because of the possibility of house reinfestation by sylvatic triatomines after insecticide treatment. This work quantiÞed the spatial distribution of triatomines in sylvatic habitats and its relationship with nearby human dwellings. A simple random sampling design using live-baited traps and manual searches for triatomines was used in areas near human communities in Manabõ ́ province, Ecuador, during June and July 2007. We identiÞed risk factors associated with triatomine density using generalized linear models, and developed predictive maps for triatomine density interpolation. There were 345 triatomines belonging to the species Rhodnius ecuadoriensis and Panstrongylus howardi collected in sylvatic areas. Spatial analyses revealed an aggregated distribution pattern of the sylvatic triatomine populations (clustered mostly at a distance smaller than 100 m). Generalized linear models showed that the distance from the nearest house, nest type, and height from ground level were the main factors explaining triatomine densities. Squirrel nests (Sciurus stramineus), located in plants other than palms, above 5 m and close to the domicile presented higher infestation. Interpolation maps of triatomine microdistribution are presented as potential tools to predict triato- mine occurrence. The presence of sylvatic populations and the synanthropic tendency of the vectors highlight the need for continuous active and passive entomological surveillance for the long-term control of Chagas disease.Item Open Access The Impact of Conservation on the Status of the World´s Vertebrates(2010) Ron Melo, Santiago Rafael; Hoffman, MichaelUsing data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world’s vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species.Item Open Access Hemidactylus mabouia MOREAU DE JONNES, 1818 and H. Frenatus SCHLEGEL, 1836 in western Ecuador: new records reveal range extension(2010) Torres Carvajal, Lenin Omar; Carvajal-Campos, AmarantaThe name Hemidactylus (GRAY, 1845) specifies a group of nocturnal geckos occurring naturally through much of tropical Asia and Africa (CARRANZA & ARNOLD 2006). This genus comprises more than 80 species, eight of which are known as successful invasive species, H. mabouia (MOREAU DE JONNÈS, 1818), H. frenatus SCHLEGEL in DUMÉRIL & BIBRON, 1836, H. turcicus (LINNAEUS, 1758), H. brookii GRAY, 1845, H. garnotii DUMÉRIL & BIBRON, 1836, H. persicus ANDERSON, 1872, H. flaviviridis RÜPPELL, 1835, and H. bowringii (GRAY, 1845) (CARRANZA & ARNOLD 2006). These species are frequently found in human settlements, therefore their invasive range could well be the result of human introduction, along with some natural transmarine journeys (CAR- RANZA & ARNOLD 2006). Displacement of native species by invasive Hemidactylus has been suggested (BALDO et al. 2008), and there are some cases, in which the introduction of H. mabouia and H. frenatus has affected natural populations of lizards, irrespective of their ecology and biology (PETREN et al. 1993; CASE et al. 1994; MESHAKA 2000).Item Open Access Microdistribution of Sylvatic Triatomine populations in Central-Coastal Ecuador(2010) Grijalva Cobo, Mario Javier; Suarez-Dávalos, Victoria.Chagas disease is a serious public health problem in Ecuador, where nearly 230,000 individuals show Trypanosoma cruzi infection. Sylvatic T. cruzi transmission is a threat to current control strategies. This is because of the possibility of house reinfestation by sylvatic triatomines after insecticide treatment. This work quantiÞed the spatial distribution of triatomines in sylvatic habitats and its relationship with nearby human dwellings. A simple random sampling design using live-baited traps and manual searches for triatomines was used in areas near human communities in Manabõ ́ province, Ecuador, during June and July 2007. We identiÞed risk factors associated with triatomine density using generalized linear models, and developed predictive maps for triatomine density interpolation. There were 345 triatomines belonging to the species Rhodnius ecuadoriensis and Panstrongylus howardi collected in sylvatic areas. Spatial analyses revealed an aggregated distribution pattern of the sylvatic triatomine populations (clustered mostly at a distance smaller than 100 m). Generalized linear models showed that the distance from the nearest house, nest type, and height from ground level were the main factors explaining triatomine densities. Squirrel nests (Sciurus stramineus), located in plants other than palms, above 5 m and close to the domicile presented higher infestation. Interpolation maps of triatomine microdistribution are presented as potential tools to predict triato- mine occurrence. The presence of sylvatic populations and the synanthropic tendency of the vectors highlight the need for continuous active and passive entomological surveillance for the long-term control of Chagas disease.Item Open Access Small Mammals of Santa Rosa, Southwestern Imbabura Province, Ecuador.(2010) Burneo Núñez, Santiago Fernando; Lee, Thomas E.In 2008 a mammal survey was conducted in humid tropical forest on the western slope of the Andes near the town of Santa Rosa. Sherman traps, tomahawk traps, pitfall traps, and mist nets were used to collect mammal specimens at two sites (450 m elevation and 702 m elevation). A total of 113 specimens of 32 species were collected from the survey area. Seventeen Chiropteran species (Saccopteryx bilineata, Anoura fistulata, Glossophaga soricina, Micronycteris megalotis, Phyllostomus discolor, Carollia perspicillata, Sturnira bogotensis, Sturnira luisi, Artibeus jamaicensis, Dermanura rava, Dermanura rosenberfii, Platyrrhinus vittatus, Vampyriscus nymphaea, Vampyressa thyone, Eumops auripendulus, Eptesicus innoxius, and Myotis albascens) and one rodent species (Sigmodontomys aphrastus) represent new records for southwestern Imbabura. New elevation records also were documented for Anoura fistulata and Sturnira bogotensis. Shannon diversity analyses of the Chiropteran fauna and overall mammal diversity indicated greater diversity at the 450 m site.Item Open Access Patrón preliminar de distribución del busardo dosirrojo Buteo polyosoma en Ecuador(2010) De Vries Postma, Tjitte; Buitrón-Jurado, Galo.Se establece el patrón de distribución del busardo dorsirrojo Buteo polyosoma en Ecua- dor. Mediante revisión de registros de especímenes y observaciones en el país, se establece la distribución de las dos formas de esta especie, B. polyosoma peruviensis y B. polyosoma polyosoma. Ambas formas tu- vieron un patrón de distribución disjunta en el Ecuador, con la forma peruviensis restringida a la región suroccidental, entre los 0 y 1.000 m.s.n.m., mientras la forma nominal se distribuyó a lo largo del callejón interandino, hasta los 3.500 m.s.n.m. Localidades importantes para la especie fueron el área del Volcán Pichincha, el Valle de Yunguilla y los alrededores de Ambato, de donde provienen un mayor número de especímenes para la forma nominal, y el área de la Península de Santa Elena para la forma peruviensis. Esta distribución confirma la preferencia por hábitats xerofíticos de Buteo polyosoma. Ambas formas podrían tener un área de contacto en el suroccidente de Loja, donde existen condiciones ambientales idóneas para la presencia de ambas formas, pero hasta el momento no existen especímenes que lo confirmen.Item Open Access Biological Invasions in the Amazonian Tropical Rain Forest: The Case of Drosophilidae (Insecta, Diptera) in Ecuador, South America(2010) Rafael Hidalgo, Violeta Lily; Rafael Hidalgo, Violeta LilyThere have been few reports of invasions in continental rain forests, especially for exotic animals. This study provides original data concerning the potential of exotic drosophilid species to colonize the Amazonian tropical rain forest. To investigate if the structure of drosophilid assemblages differed in response to anthropogenic disturbance, we performed a taxonomic survey at six sites within the Yasuni National Park in Ecuadorian Amazonia along a disturbance gradient from pristine to clearcut artificial forest. A total of 7425 individuals from 34 species were collected of which seven species were exotic. There was significant variation in the assemblage com- position along this disturbance gradient; 31 percent of which was explained by the presence of exotic species, particularly at the most disturbed sites, through nonmetric multidimensional scaling and SIMPER analyses. These results confirm the susceptibility of continental rain forests to invasion by exotic species. There is an urgent need to develop and implement monitoring systems, for example, based on drosophilid assemblage surveys, to detect exotic invasions in continental tropical forests.Item Open Access Five new (extinct?) species of Atelopus (Anura: Bufonidae) from Andean Colombia, Ecuador, and Peru(2010) Ron Melo, Santiago Rafael; Coloma, Luis A.We studied populations of frogs of the genus Atelopus from the Pasto Massif of the Andes in southern Colombia and north- ern Ecuador, and from the Huancabamba depression in southern Ecuador and northern Perú and conclude that they belong to six species, five of which are described as new to science. Atelopus angelito is recorded for the first time from Ecuador and its range is extended 183 km (airline) southwest of its type locality in Departamento del Cauca, Colombia. We distin- guish the five new species from similar ones using features of coloration, skin texture, and morphometrics. We also in- clude osteological data for four of the new species. A putative hybrid zone at Provincia Imbabura, Ecuador, is proposed to exist between the non-sister taxa A. ignescens and one of the new species. Because recent records of four of the new species and A. angelito are lacking despite search efforts, we hypothesize that they are possibly extinct, as are many other Andean Atelopus. Thus, we categorize these species, applying IUCN Red List criteria, as Critically Endangered (Possibly Extinct). No search efforts have been carried out for one new species (from La Victoria, Colombia); thus, it is included under the Data Deficient category. The conservation of Atelopus is briefly discussed.Item Open Access Influencia de Algunos Ácidos Orgánicos sobre las Propiedades Físico-Químicas de Películas de Quitosano Obtenidas a Partir de Desechos de Cangrejo(2010) Meneses Olmedo, Lorena Maribel; Araya, A.El objetivo de este estudio fue conocer la influencia de los ácidos acético, fórmico y láctico en las características físico-químicas de películas de quitosano. Para el efecto se realizaron los tratamientos de desmineralización, desproteinización y despigmentación de desechos de cangrejo rojo (Ucides Occidentalis Ortmam) para obtener quitina, la cual fue desacetilada con hidróxido de sodio 50 % p/v para obtener quitosano. Este quitosano fue caracterizado por las técnicas de espectroscopía de absorción de infrarrojos y titulación potenciométrica, obteniendo valores de grado de desacetilación promedio de 67.0 % y 62.7 % respectivamente. Se determinó el peso molecular por el método viscosimétrico con un valor promedio de 1.26*105 g/mol del polímero. Para formar películas transparentes, se utilizaron soluciones 5% v/v de ácido fórmico, ácido acético y ácido láctico. Las películas presentaron mayor resistencia tensil al ser tratadas con ácido acético y ácido láctico. Por espectroscopía de infrarrojos se logró apreciar las bandas características de las películas de quitosano, demostrando que la parte estructural química tiene ligeras variaciones dependiendo del ácido utilizado para su formación.Item Open Access Ciprofloxacin susceptibility reduction of Salmonella strains isolated from outbreaks(2010) Alcocer Negrete, Iliana del Rocío; Souza, Roberta B.The antimicrobial susceptibility of 212 Salmonella strains isolated from patients and foods was evaluated and 45% were found to be resistant to nalidixic acid. Nalidixic acid resistant strains showed an higher minimal inhibitory concentration for ciprofloxacin than sensitive strains. During the study an increase of strains with reduced susceptibility to ciprofloxacin was also observed.Item Open Access Sobre la especiación del águila mora Gerranoaetus melanoleucus y los busardos de cola blanca(2010) De Vries Postma, Tjitte; Cabot, José.En vista de que: (1) Buteo poecilochrous y B. Polysoma tienen secuencias idénticas de bases en el citocromo B mitocondrial, 606 y 620 pares de bases secuenciadas (Riesing et al., 2003) y Cabot y de Vries (2008) respectivamente; (2) que B. Albicaudatus difiere de los anteriores en sólo dos pares de bases de esta secuencia (Cabot y de Vries, 2008); y (3) la tasa de mutación del ADN mitocondrial es 2 al 10% por millón de años (Irving et al., 1991), queda en evidencia, en primer lugar, que las especies se han diferenciado recientemente, especialmente las dos primeras y, en segundo lugar, que este marcador genético no sirve para este caso, pues no ha habido tiempo para cambios substanciales que dejaran su huella en las secuencias de bases del citocromo B.