Ecological host fitting of Trypanosoma cruzi TcI in Bolivia: mosaic population structure, hybridization and a role for humans in Andean parasite dispersal.

An improved understanding of how a parasite species exploits its genetic repertoire to colonize novel hosts and environmental niches is crucial to establish the epidemiological risk associated with emergent pathogenic genotypes. Trypanosoma cruzi, a genetically heterogeneous, multi-host zoonosis, provides an ideal system to examine the sylvatic diversification of parasitic protozoa. In Bolivia, T. cruzi I, the oldest and most widespread genetic lineage, is pervasive across a range of ecological clines. High-resolution nuclear (26 loci) and mitochondrial (10 loci) genotyping of 199 contemporaneous sylvatic TcI clones was undertaken to provide insights into the biogeographical basis of T. cruzi evolution. Three distinct sylvatic parasite transmission cycles were identified: one highland population among terrestrial rodent and triatomine species, composed of genetically homogenous strains (Ar = 2.95; PA/L = 0.61; DAS = 0.151), and two highly diverse, parasite assemblages circulating among predominantly arboreal mammals and vectors in the lowlands (Ar = 3.40 and 3.93; PA/L = 1.12 and 0.60; DAS = 0.425 and 0.311, respectively). Very limited gene flow between neighbouring terrestrial highland and arboreal lowland areas (distance ~220 km; FST = 0.42 and 0.35) but strong connectivity between ecologically similar but geographically disparate terrestrial highland ecotopes (distance >465 km; FST = 0.016-0.084) strongly supports ecological host fitting as the predominant mechanism of parasite diversification. Dissimilar heterozygosity estimates (excess in highlands, deficit in lowlands) and mitochondrial introgression among lowland strains may indicate fundamental differences in mating strategies between populations. Finally, accelerated parasite dissemination between densely populated, highland areas, compared to uninhabited lowland foci, likely reflects passive, long-range anthroponotic dispersal. The impact of humans on the risk of epizootic Chagas disease transmission in Bolivia is discussed

Empresa Andrews y su estrategia en el simulador Capstone

El presente trabajo de obtención de grado comprende el análisis de la planeación estratégica, toma de decisiones y resultados obtenidos en el simulador de negocios Capstone, lo cual recopila conocimientos teóricos y prácticos obtenidos en la maestría de administración de empresas con especial énfasis en aquellos enfocados a estrategia. El primer capítulo, presenta el marco teórico de la planeación estratégica y definición de esta; abordando temas como liderazgo, indicadores dentro de la organización, estrategias genéricas, entre otros. También se utilizan algunos ejemplos de casos de empresas relevantes, aterrizando los conceptos mencionados. El capítulo dos, es referente al simulador de Capstone, donde se explica la industria, funcionamiento, criterios de compra, segmentos, departamentos y la importancia de la toma de decisiones. También se revisan los reportes de resultados y métricos de la competencia. Así como la planeación estratégica realizada por el equipo Andrews. Los capítulos tres al seis, contienen los resultados bianuales obtenidos por el grupo, así como de la industria, los cuales se traducen en análisis internos y externos así como la evaluación constante de la estrategia elegidaITESO, A.C

Trypanosoma cruzi IIc: phylogenetic and phylogeographic insights from sequence and microsatellite analysis and potential impact on emergent Chagas disease.

Trypanosoma cruzi, the etiological agent of Chagas disease, is highly genetically diverse. Numerous lines of evidence point to the existence of six stable genetic lineages or DTUs: TcI, TcIIa, TcIIb, TcIIc, TcIId, and TcIIe. Molecular dating suggests that T. cruzi is likely to have been an endemic infection of neotropical mammalian fauna for many millions of years. Here we have applied a panel of 49 polymorphic microsatellite markers developed from the online T. cruzi genome to document genetic diversity among 53 isolates belonging to TcIIc, a lineage so far recorded almost exclusively in silvatic transmission cycles but increasingly a potential source of human infection. These data are complemented by parallel analysis of sequence variation in a fragment of the glucose-6-phosphate isomerase gene. New isolates confirm that TcIIc is associated with terrestrial transmission cycles and armadillo reservoir hosts, and demonstrate that TcIIc is far more widespread than previously thought, with a distribution at least from Western Venezuela to the Argentine Chaco. We show that TcIIc is truly a discrete T. cruzi lineage, that it could have an ancient origin and that diversity occurs within the terrestrial niche independently of the host species. We also show that spatial structure among TcIIc isolates from its principal host, the armadillo Dasypus novemcinctus, is greater than that among TcI from Didelphis spp. opossums and link this observation to differences in ecology of their respective niches. Homozygosity in TcIIc populations and some linkage indices indicate the possibility of recombination but cannot yet be effectively discriminated from a high genome-wide frequency of gene conversion. Finally, we suggest that the derived TcIIc population genetic data have a vital role in determining the origin of the epidemiologically important hybrid lineages TcIId and TcIIe

Evaluation of explotation system in an autochthonous goat group of milk production

In the present study we have done an evaluation of the farms in an region of the north of Córdoba (Spain). Twenty five farms with principally murciano-granadina breed, have been visited. In these farms, we have done an inquiry with 310 questions. This inquiry is structured in three sections; one of those has 150 management variables, another one has 100 health variables and the last one has 60 technologic variables. Farms have been clasiffied in three groups in relation to the succesfull events distribution for each group of variables. The clasification system, which has been contrasted by discriminant analysis, let us include the farms while they are incorporating in the program. This is a results in a simple way to apply a different action plan in each group of farms.En este estudio se ha realizado una evaluación de las ganaderías de una comarca del norte de la provincia de Córdoba. Se han visitado 25 explotaciones de ganado caprino lechero, principalmente de raza Murciano-Granadina, en las que se ha realizado una encuesta que contiene un total de 310 preguntas. Dicha encuesta se encuentra estructurada en tres partes, 150 aspectos de manejo, 100 aspectos sanitarios y 60 aspectos tecnológicos. Las explotaciones se han clasificado en tres grupos según la distribución de los sucesos favorables para cada grupo de variables. Este sistema de clasificación, que ha sido contrastado mediante análisis discriminante, permite ir incluyendo ganaderías que se incorporen en un futuro, y resulta una forma sencilla de aplicar un plan de actuaciones diferente para cada grupo de ganaderías

Bird species richness in High-Andean forest fragments : habitat quality and topography matter

Montane forests worldwide are known centers of endemism and biodiversity but are highly threatened by fragmentation processes. Using data collected in 15 Polylepis forest remnants covering 2000 hectares, we investigated how bird species richness and bird community composition, particularly for species of conservation concern, are influenced by habitat quality and topography in the Tunari National Park in the High Andes of Bolivia. Bird species richness was highest in topographically complex, low-elevation Polylepis patches located in areas with a high potential to retain rainwater. Bird communities differed strongly between Polylepis lanata and P. subtusalbida remnants, each supporting different threatened and endemic species. Within the P. subtusalbida forest, high-elevation fragments characterized by high amounts of sunlight and low anthropogenic disturbance were more likely to contain threatened species. Surprisingly, we found no effect of fragment size on the diversity or composition of bird communities or the presence of bird species of conservation concern. The presence of exotic plantations (Pinus and/or Eucalyptus spp.) in or outside forest remnants was negatively associated with the number of bird species as well as with occurrence of the endangered Cochabamba-mountain finch (Compsospiza garleppi). To support the different communities found in Polylepis forests, these results suggest that conservation efforts should be directed towards both forest types (P. subtusalbida and P. lanata) present in the area. For an efficient management of avian diversity, exotic plantations should be established away from native remnants while existing patches should be managed to maintain or increase habitat quality. Finally, the importance of local topography in determining avian species richness and community composition in forest fragments, mainly through topographic controls on moisture distribution and the amount of sunlight received by the fragments, should be considered when planning conservation and reforestation schemes