A spatial scale assessment of habitat effects on arthropod communities of an oceanic island

Copyright © 2009 Elsevier Masson SAS. All rights reserved.Most habitats in the Azores have undergone substantial land-use changes and anthropogenic disturbance during the last six centuries. In this study we assessed how the richness, abundance and composition of arthropod communities change with: (1) habitat type and (2) the surrounding land-use at different spatial scales. The research was conducted in Terceira Island, Azores. In eighty-one sites of four different habitat types (natural and exotic forests, semi-natural and intensively managed pastures), epigaeic arthropods were captured with pitfall traps and classified as endemic, native or introduced. The land-use surrounding each site was characterized within a radius ranging from 100 to 5000 m. Non-parametric tests were used to identify differences in species richness, abundance and composition between habitat types at different spatial scales. Endemic and native species were more abundant in natural forests, while introduced species were more abundant in intensively managed pastures. Natural forests and intensively managed pastures influenced arthropod species richness and composition at all spatial scales. Exotic forests and semi-natural pastures, however, influenced the composition of arthropod communities at larger scales, promoting the connectivity of endemic and native species populations. Local species richness, abundance and composition of arthropod communities are mostly determined by the presence of nearby natural forests and/or intensively managed pastures. However, semi-natural pastures and exotic forests seem to play an important role as corridors between natural forests for both endemic and native species. Furthermore, exotic forests may serve as a refuge for some native species

Invasibility and species richness of island endemic arthropods: a general model of endemic vs. exotic species

Copyright © 2005 Blackwell Publishing.This paper has two objectives. First, we examine how a variety of biotic, abiotic and anthropogenic factors influence the endemic and introduced arthropod richness on an oceanic island. Second, we look at the relationship between the endemic and introduced arthropod richness, to ask whether areas with high levels of endemic species richness deter invasions

Preacondicionamiento de la semilla de arveja (pisum sativum l.)

En el Centro de Investigación "La selva ", de la Corporación Colombiana de Investigación Agropecuaria. CORPOICA, ubicado en Rionegro, Antioquia. a 2120 msnm, con una temperatura promedio de 17 °C y perteneciente a la formación ecológica Bosque Húmedo Montano Bajo, se llevó a cabo un estudio con la especie arveja (Pisum sativum L.), con el fin de evaluar el efecto del tratamiento de preacondicionamiento de las semillas, conocido como humedecimiento-secado, sobre la germinación, la emergencia y el establecimiento de plantas. Adicionalmente se evaluó el procedimiento con diferentes concentraciones del fungicida sistémico benomyl, en comparación con agua destilada, buscándose reducir la pérdida de plantas durante el período de establecimiento del cultivo, y se midió el efecto de los tratamientos con y sin fungicida sobre el rendimiento, en comparación con plantas provenientes de semilla no preacondicionada. A nivel de laboratorio se encontró que el tratamiento que produjo mayor velocidad de germinación fué la imbibición hasta el 75% de peso de la semilla, con secado posterior hasta recobrar el peso inicial. Utilizando el tratamiento anterior, se halló que la adición de benomyl, en diferentes concentraciones, no afectó la velocidad de germinación ni la germinación total, incrementándose el porcentaje de plantas sanas obtenidas en comparación con el preacondicionamiento sin fungicida, con valores máximos al imbibir con una solución de benomyl al 0.1%. En el campo no se observó efecto de los tratamientos de preacondicionamiento con y sin fungicida sobre la velocidad de emergencia y la emergencia total, reduciendo los tratamientos con fungicida la incidencia de plantas muertas en forma sensible con una respuesta diferencial en rendimiento, por parte de las dos variedades estudiadas, al aplicar los diversos procedimientos de preacondicionamiento. Así, mientras que con el cultivar 'Small Sieve All Sweet ', no hubo efecto en la productividad por parte de los tratamientos, éste fué evidente en el cultivar 'Bogotana', con rendimiento máximo en las plantas provenientes de semilla preacondicionada con una solución de benomyl al 0.05%

Diferentes Integrações de Laboratórios Remotos em Cursos de Engenharia

Este artigo aborda diferentes integrações do VISIR. O VISIR é um laboratório aberto remoto dedicado a experimentos com circuitos elétricos e eletrónicos. Este laboratório permite que professores e alunos tenham oportunidade de contatar com experimentos remotamente e em tempo real, com equipamentos de teste e medição (fonte de alimentação tripla DC, gerador de funções, multímetro e um osciloscópio) ligado a componentes elétricos e eletrónicos. As abordagens didáticas são resumidas e as análises feitas fornecem explicações para alguns dos problemas encontrados, além de algumas diretrizes para futuras implementações. Uma série de pontos fortes e fracos é destacada, levando a sugestões sobre como aprimorar algumas abordagens estratégicas para motivar professores e motivar alunos para o potencial da utilização do VISIR no ensino e na aprendizagem. São apresentadas referências apropriadas para trabalhos publicados anteriormente que ajudam a entender o contexto de pesquisa e as lições derivadas de um uso mais intensivo do VISIR.info:eu-repo/semantics/publishedVersio

Morphologic characterization of tomato tree (Cyphomandra betacea Sendt. Solanaceae)

El desarrollo de los agricultores de las áreas montañosas andinas depende de la oferta de alternativas productivas que permitan capitalizar a los productores, aspecto que difícilmente se puede lograr con las especies anuales sembradas por ellos. Entre las especies con posibilidades para cambiar la situación expuesta se ha identificado un grupo de frutas, que incluyen el tomate de árbol, taxón originario de dicha zona (13, 2). Las posibilidades de este frutal se derivan de su aceptación en los mercados, los precios rentables, relativamente estables y de las posibilidades de su utilización no solo como fruta fresca, sino también en la forma de procesados, lo cual le da un valor agregado a dicha especie. Entre los aspectos que han dificultado su desarrollo se encuentran: oferta nula o escasa de variedades o clones con alta capacidad productiva, falta de calidad de los frutos y uniformidad de las bayas y problemas epidemiológicos, entre los cuales se destacan la antracnosis de las bayas, causada por el hongo Colletotrichum gloesporioides. Esta causa pérdidas totales cuando no se aplican medidas de control, fluctuando las mismas entre el 10 y el 25% en los casos en los cuales se aplican fungicidas protectantesTomate de árbol-Cyphomandra betace

Methicillin-resistant Staphylococcus aureus (MRSA) carriage in a dermatology unit

OBJECTIVE: The aim of this study was to characterize Staphylococcus aureus (MRSA) carriage in a dermatology unit. METHODS: This was a prospective and descriptive study. Over the course of 26 weeks, surveillance cultures were collected weekly from the anterior nares and skin of all patients hospitalized in a 20-bed dermatology unit of a tertiary-care hospital. Samples from healthcare workers (HCWS) were cultured at the beginning and end of the study. Colonized patients were put under contact precautions, and basic infection control measures were enforced. Staphylococcus aureus colonization pressure was determined monthly. Colonized and non-colonized patients were compared, and isolates were evaluated for antimicrobial susceptibility, SCCmec type, virulence factors, and type. RESULTS: Of the 142 patients evaluated, 64 (45%) were colonized by MRSA (39% hospital acquired; 25% community acquired; 36% indeterminate). Despite isolation precautions, hospital-acquired Staphylococcus aureus occurred in addition to the continuous entry of Staphylococcus aureus from the community. Colonization pressure increased from 13% to 59%, and pemphigus and other bullous diseases were associated with MRSA colonization. Eleven out of 71 HCWs (15%) were Staphylococcus aureus carriers, although only one worker carried a persistent clone. Of the hospital-acquired MRSA cases, 14/28 (50%) were SCCmec type IV (3 PFGE types), 13 were SCCmec type III (46%), and one had an indeterminate type. These types were also present among the community-acquired Staphylococcus aureus isolates. SSCmec type IV isolates were shown to be more susceptible than type III isolates. There were two cases of bloodstream infection, and the pvl and tst virulence genes were absent from all isolates. CONCLUSIONS: Dermatology patients were colonized by community- and hospital-acquired Staphylococcus aureus. Half of the nosocomial Staphylococcus aureus isolates were SCCmec type IV. Despite the identification of colonized patients and the subsequent contact precautions and room placement, Staphylococcus aureus colonization continued to occur, and colonization pressure increased. Pemphigus and other bullous diseases were associated with Staphylococcus aureus

development of an occupational health risk management program

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Human adaptation to immobilization: Novel insights of impacts on glucose disposal and fuel utilization

Background: Bed rest (BR) reduces whole-body insulin-stimulated glucose disposal (GD) and alters muscle fuel metabolism, but little is known about metabolic adaptation from acute to chronic BR nor the mechanisms involved, particularly when volunteers are maintained in energy balance. Methods: Healthy males (n=10, 24.0±1.3years), maintained in energy balance, underwent 3-day BR (acute BR). A second cohort matched for sex and body mass index (n=20, 34.2±1.8years) underwent 56-day BR (chronic BR). A hyperinsulinaemic euglycaemic clamp (60mU/m2/min) was performed to determine rates of whole-body insulin-stimulated GD before and after BR (normalized to lean body mass). Indirect calorimetry was performed before and during steady state of each clamp to calculate rates of whole-body fuel oxidation. Muscle biopsies were taken to determine muscle glycogen, metabolite and intramyocellular lipid (IMCL) contents, and the expression of 191 mRNA targets before and after BR. Two-way repeated measures analysis of variance was used to detect differences in endpoint measures. Results: Acute BR reduced insulin-mediated GD (Pre 11.5±0.7 vs. Post 9.3±0.6mg/kg/min, P<0.001), which was unchanged in magnitude following chronic BR (Pre 10.2±0.4 vs. Post 7.9±0.3mg/kg/min, P<0.05). This reduction in GD was paralleled by the elimination of the 35% increase in insulin-stimulated muscle glycogen storage following both acute and chronic BR. Acute BR had no impact on insulin-stimulated carbohydrate (CHO; Pre 3.69±0.39 vs. Post 4.34±0.22mg/kg/min) and lipid (Pre 1.13±0.14 vs. Post 0.59±0.11mg/kg/min) oxidation, but chronic BR reduced CHO oxidation (Pre 3.34±0.18 vs. Post 2.72±0.13mg/kg/min, P<0.05) and blunted the magnitude of insulin-mediated inhibition of lipid oxidation (Pre 0.60±0.07 vs. Post 0.85±0.06mg/kg/min, P<0.05). Neither acute nor chronic BR increased muscle IMCL content. Plentiful mRNA abundance changes were detected following acute BR, which waned following chronic BR and reflected changes in fuel oxidation and muscle glycogen storage at this time point. Conclusions: Acute BR suppressed insulin-stimulated GD and storage, but the extent of this suppression increased no further in chronic BR. However, insulin-mediated inhibition of fat oxidation after chronic BR was less than acute BR and was accompanied by blunted CHO oxidation. The juxtaposition of these responses shows that the regulation of GD and storage can be dissociated from substrate oxidation. Additionally, the shift in substrate oxidation after chronic BR was not explained by IMCL accumulation but reflected by muscle mRNA and pyruvate dehydrogenase kinase 4 protein abundance changes, pointing to lack of muscle contraction per se as the primary signal for muscle adaptation

Aportes al conocimiento del sistema productivo de cultivo de la mora (Rubus glaucus Benth) en Colombia

Varios estudios que examinan el cultivo de la mora en Colombia muestran que esta actividad es realizada por pequeños y medianos agricultores. En muchas regiones constituye una de las principales fuentes de ingresos; generación de empleo rural; oferta de alimento y de agroindustria. En este trabajo se revisaron más de 180 documentos distribuidos entre artículos divulgativos, técnicos y científicos, publicados en boletines, manuales, cartillas, seminarios y cursos; además, resultados de trabajos de investigación, tesis de pregrado y artículos científicos publicados en revistas seriadas e indexadas. Este es resultado de la búsqueda la literatura de la agronomía del sistema productivo de la mora en la red, en la Biblioteca Agropecuaria de Colombia (BAC), en las bibliotecas de de la Universidad Nacional de Colombia y en las bibliotecas de los investigadores del CI La Selva de Corpoica. Para analizar la literatura sobre la agronomía y las prácticas de manejo agronómico de la mora (distribución espacial, trazado y siembra, propagación, tutorado, poda, entre otras). Del manejo agronómico se han escrito diversas publicaciones unas más profundas que otras, estas se caracterizan porque para la mayoría de las practicas agronómicas se carece de un sustento que las valide, para los diferentes ambiente y genotipos y muchas de ellas son el resultado de la observación, del sentido común y de adaptación de otro sistema productivo. Esta literatura surge en la década de 50’s, en la de los 70’ se dan las versiones más integrales del sistema productivo y durante la década de los 90’s, es el periodo dorado cuando se consolida y se presentan los trabajos mas completos, aun todavía faltando, la integralidad entre genotipo, ambiente y la interacción entre estos.Mora-Rubus ulmifoliu