522 research outputs found

    Efecto del tamaño de tamiz en la caracterización de la macrofauna marina bentónica: Implicancias para su uso en líneas de base, caracterizaciones preliminares de sitios para la acuicultura y monitoreos ambientales en Chile

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    Las características ecológicas de la macrofauna bentónica, la convierten en un buen indicador para evaluar los efectos de perturbaciones antropogénicas (e.g., acuicultura, emisarios submarinos, etc.) sobre los ecosistemas marinos. La normativa chilena aplicable a monitoreos ambientales establece que su caracterización debe realizarse utilizando tamices de 1.000 µm de abertura. Con el objetivo de evaluar la pérdida de información en composición y abundancia de las especies al utilizar este tamiz respecto de uno de 500 µm, se realizaron muestreos submareales en invierno y verano del 2018 en 5 áreas del Golfo de Arauco, Chile central. El muestreo y análisis consistió en: (i) cernido en tamiz de 1.000 µm, reteniendo los organismos que traspasan este tamiz en uno de 500 µm, (ii) identificación de los organismos retenidos en ambos tamices hasta el nivel taxonómico más bajo posible y, (iii) comparación de la macrofauna entre tamices, períodos y áreas de muestreo, utilizando estadística univariada y multivariada. A partir de los análisis se encontraron diferencias significativas en la estructura comunitaria de la macrofauna entre tamices, áreas y periodos de muestreo. Los índices AMBI y W, utilizados como bio-indicadores comunitarios, también identifican diferencias significativas entre tamices. Los resultados señalan que, si bien el uso de un tamiz de 1.000 µm permite identificar diferencias espaciales y temporales en la macrofauna, con su uso se subestima el nivel de impacto detectado por los bio-indicadores comunitarios. Por tal razón, se recomienda utilizar un tamiz de 500 µm si el objetivo es evaluar impactos antropogénicos en el ambiente marino, especialmente en líneas de base, caracterizaciones preliminares de sitio para la acuicultura y programas de vigilancia ambiental. Toda la información, debiera, además, ser integrada mediante herramientas estadísticas multivariadas, capaces de incorporar en conjunto los antecedentes biológicos y ambientales recopilados en el área de estudio

    Diet and SIRT1 Genotype Interact to Modulate Aging-Related Processes in Patients with Coronary Heart Disease: From the CORDIOPREV Study

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    We investigated whether long-term consumption of two healthy diets (low-fat (LF) or Mediterranean (Med)) interacts with SIRT1 genotypes to modulate aging-related processes such as leucocyte telomere length (LTL), oxidative stress (OxS) and inflammation in patients with coronary heart disease (CHD). LTL, inflammation, OxS markers (at baseline and after 4 years of follow-up) and SIRT1-Single Nucleotide Polymorphisms (SNPs) (rs7069102 and rs1885472) were determined in patients from the CORDIOPREV study. We analyzed the genotype-marker interactions and the effect of diet on these interactions. Regardless of the diet, we observed LTL maintenance in GG-carriers for the rs7069102, in contrast to carriers of the minor C allele, where it decreased after follow-up (p = 0.001). The GG-carriers showed an increase in reduced/oxidized glutathione (GSH/GSSG) ratio (p = 0.003), lower lipid peroxidation products (LPO) levels (p < 0.001) and a greater decrease in tumor necrosis factor-alpha (TNF-α) levels (p < 0.001) after follow-up. After the LF diet intervention, the GG-carriers showed stabilization in LTL which was significant compared to the C allele subjects (p = 0.037), although the protective effects found for inflammation and OxS markers remained significant after follow-up with the two diets. Patients who are homozygous for the SIRT1-SNP rs7069102 (the most common genotype) may benefit from healthy diets, as suggested by improvements in OxS and inflammation in patients with CHD, which may indicate the slowing-down of the aging process and its related diseases

    Influencia de variables meteorológicas sobre el rendimiento de la caña de azúcar

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    Se  seleccionaron   14   ingenios   azucareros  pertenecientes   a  las   provincias   Artemisa, Mayabeque y Matanzas, con sus respectivas estaciones meteorológicas asociadas. Los datos anuales de rendimiento agrícola e industrial de la caña de azúcar y los registros diarios de precipitaciones y temperaturas en el período comprendido entre 1980 y 2011 (30 años), sirvieron de base para el estudio. El análisis de los datos arrojó que en todo el período, la temperatura máxima (Tmáx) no experimentó cambios, la temperatura media (Tm) aumentó en 0,93ºC, mientras que la temperatura mínima (Tmín) lo hizo en 0,62ºC y la amplitud térmica  (AT)  se  redujo  en  0,72ºC.  De  todas  las  regiones  estudiadas,  la  estación meteorológica de Bahía Honda fue la que mostró los menores valores de AT. Las precipitaciones incrementaron en 33,78%, mientras que RA disminuyó en 52,83% con relación a su valor inicial. Se encontró una dependencia inversa entre la AT y la Tmín, mientras que hubo una fuerte dependencia entre RI y Prec (97%) en las tres provincias. Estas últimas, 10 días antes de la cosecha, tuvieron un ligero efecto negativo sobre RI, en tanto que, éste no fue prácticamente afectado. Se concluyó que la provincia Matanzas fue la que presentó las mejores condiciones climáticas para el cultivo de la caña de azúcar y dentro de ella, la zona más propicia para su desarrollo fue el municipio Jovellanos

    Eco-epidemiological analysis of rickettsial seropositivity in rural areas of Colombia: A multilevel approach

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    ABSTARCT: Rickettsiosis is a re-emergent infectious disease without epidemiological surveillance in Colombia. This disease is generally undiagnosed and several deadly outbreaks have been reported in the country in the last decade. The aim of this study is to analyze the eco-epidemiological aspects of rickettsial seropositivity in rural areas of Colombia where outbreaks of the disease were previously reported. A cross-sectional study, which included 597 people living in 246 households from nine hamlets in two municipalities of Colombia, was conducted from November 2015 to January 2016. The survey was conducted to collect sociodemographic and household characteristics (exposure) data. Blood samples were collected to determine the rickettsial seropositivity in humans, horses and dogs (IFA, cut-off = 1/128). In addition, infections by rickettsiae were detected in ticks from humans and animals by real-time PCR targeting gltA and ompA genes. Data was analyzed by weighted multilevel clog-log regression model using three levels (person, household and hamlets) and rickettsial seropositivity in humans was the main outcome. Overall prevalence of rickettsial seropositivity in humans was 25.62% (95%CI 22.11-29.12). Age in years (PR = 1.01 95%CI 1.01-1.02) and male sex (PR = 1.65 95%CI 1.43-1.90) were risk markers for rickettsial seropositivity. Working outdoors (PR = 1.20 95%CI 1.02-1.41), deforestation and forest fragmentation for agriculture use (PR = 1.75 95%CI 1.51-2.02), opossum in peridomiciliary area (PR = 1.56 95%CI 1.37-1.79) and a high proportion of seropositive domestic animals in the home (PR20-40% vs 40% vs <20% = 3.14 95%CI 2.43-4.04) were associated with rickettsial seropositivity in humans. This study showed the presence of Rickettsia antibodies in human populations and domestic animals. In addition, different species of rickettsiae were detected in ticks collected from humans and animals. Our results highlighted the role of domestic animals as sentinels of rickettsial infection to identify areas at risk of transmission, and the importance of preventive measures aimed at curtailing deforestation and the fragmentation of forests as a way of reducing the risk of transmission of emergent and re-emergent pathogens

    Evidence of association of the NLRP1 gene with giant cell arteritis

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    Recent studies have focused attention on the involvement of NLRP1 to confer susceptibility for extended autoimmune/inflammatory disorders, being considered a common risk factor in autoimmunity. NLRP1 provides a scaffold for the assembly of the inflammasome that activates caspases 1 and 5, required for processing and activation of the proinflammatory cytokines interleukin 1β (IL-1β), IL-18 and IL-33 and promoting inflammation

    Combinations of Metarhizium anisopliae with chemical insecticides and their effectiveness in Mahanarva fimbriolata (Hemiptera: Cercopidae) control on sugarcane

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    Some insecticides can be used jointly with entomopathogenic fungi, and therefore the combi- nation of chemical and biological control measures can be a safe and effective method to con- trol insect pests. The aim of this study was to evaluate the costs and efficacy of combinations of Metarhizium anisopliae (Metschnikoff) Sorokin (Hypocreales: Clavicipitaceae) with thiameth- oxam and imidacloprid on spittlebug (Mahanarva fimbriolata (Stål); Hemiptera: Cercopidae) control on sugarcane. The experiment was conducted as a randomized block design (RBD) with 10 treatments and 4 replications. The treatments included a control (untreated), thia- −1 −1 12 −1 methoxam (250 g ha ), imidacloprid (700 g ha ), M. anisopliae (M. a.) (3 × 10 conidia ha ), A1 (3 × 10 12 M. a. conidia ha −1 + 65 g ha −1 of thiamethoxam), A2 (3 × 10 12 M. a. conidia ha −1 + 125 g ha −1 of thiamethoxam), A3 (3 × 10 12 M. a. conidia ha −1 + 187.5 g ha −1 of thiamethoxam), A4 (3 × 10 12 M. a. conidia ha −1 + 175 g ha −1 of imidacloprid), A5 (3 × 10 12 M. a. conidia ha −1 + 350 g ha −1 of imidacloprid), and A6 (3 × 10 12 M. a. conidia ha −1 + 525g ha −1 of imidacloprid). The reductions in the numbers of M. fimbriolata nymphs per treatment compared to the control were similar at 15 DAT (days after treatment) in all treatments except combination A5 (M. anisopliae and thiamethoxam). At 30 DAT, the numbers of nymphs were significantly reduced in all treatments except A3, and their effectiveness ranged from 14.28% to 92.85%. At 45 DAT the numbers of M. fimbriolata nymphs per treatment were significantly reduced in the following treatments: imidacloprid alone at 700g ha -1 , A1, A2, A3, A4 and A6; and the combinations A1 and A2 caused the lowest M. fimbriolata nymph infestations and effectiveness rates of 77.41 and 87.09 %, respectively. At 75 DAT the 2 best control efficacies occurred in treatments A1 (3 × 10 12 M. a. conidia ha -1 of + 65g ha -1 of thiamethoxam) (82.1%) and A5 (78.6%) (3 × 10 12 M. a. conidia ha −1 + 350 g ha −1 of imidacloprid). At 90 DAT the number of nymphs in the control had increased 2.8 fold over the number at 75 DAT. Very good control efficacies at 90 DAT occurred in all treatments with the combination of the fungus with an insecticide. At 105 DAT the numbers of nymphs had surged in all treatments, and no treatment provided effective control. The treatments with the highest earnings per hectare were A1 (3 × 10 12 M. a. conidia ha -1 + 65 g thiamethoxam) and M. anisopliae alone at the recommended dose of 3 × 10 12 M. a. conidia ha -1 . Our findings demonstrate the effectiveness of using either thiamethoxam or imidacloprid in combination with M. anisopliae to control M. fimbriolata nymphs on sugarcane, but greater net earnings per hectare occurred with the lowest rate of the thiamethoxam combination than with any of the imidacloprid combinations.Algunos insecticidas se puede utilizar con hongos entomopatógenos y por lo tanto, la aso- ciación de los controles químico y biológico puede ser una estrategia segura y eficaz para el control de insectos-plaga. El objetivo de este estudio fue evaluar los costos y eficacia de combinaciones de Metarhizium anisopliae (Metschnikoff) Sorokin (Hypocreales: Clavi- cipitaceae) con insecticidas thiamethoxam e imidacloprid para el control de la chicharrita (Mahanarva fimbriolata (Stål); Hemiptera: Cercopidae) en caña de azúcar . El experimento fue conducido en un delineamiento en bloques casualizados (DBC), con 10 tratamientos y 4 repeticiones. Los tratamientos que incluidos el control (sin tratamiento), thiamethoxam (250 g ha −1 ), imidacloprido (700 g ha −1 ), M. anisopliae (M.a.) (3×10 12 conidios ha −1 ), A1 (3×10 12 conidios ha −1 de M. a. + 65 g ha −1 de thiamethoxam), A2 (3×10 12 conidios ha −1 de M. a. + 125g ha −1 de thiamethoxam), A3 (3×10 12 conidios ha −1 de M. a. + 187.5 g ha −1 de thiamethoxam), A4 (3×10 12 conidios ha −1 de M.a + 175 g ha −1 de imidacloprido), A5 (3×10 12 conidios ha −1 de M. a. + 350 g ha −1 de imidacloprido) y A6 (3×10 12 conidios ha −1 de M. a. + 525g ha −1 de imidacloprido). Las reducciones en el número de ninfas M. fimbriolata por tratamiento en comparación con el control fueron similares a los 15 DAT (días pos tratamiento) en todos los tratamientos excepto A5 combinación (M. anisopliae y thiamethoxam). A los 30 DAT, el número de ninfas se redujeron significativamente en todos los tratamientos, excepto A3, y su eficacia varió de 14,28% para 92,85%. A los 45 DAT, los números de ninfas M. fimbriolata por tratamiento se redujeron significativamente en los siguientes tratamientos: imidacloprido solo en 700 g ha -1 , A1, A2, A3, A4 y A6; y las combinaciones de A1 y A2 causaron la más bajo infestaciones de ninfas M. fimbriolata y sus tasas de eficacia fueron de 77,41 y 87,09%, respectivamente. A los 75 DAT, los 2 mejores eficacias de control se produjeron en tratamientos A1 (3×10 12 conidios ha −1 de M. a. + 65 g ha −1 de thiamethoxam) y A5 (78.6%) (3×10 12 conidios ha −1 de M. a.+ 350 g ha −1 de imidacloprido). A los 90 DAT, el número de ninfas en el control había aumentado 2,8 veces más el número a 75 DAT. Muy buenas eficacias de control en 90 DAT, se produjo en todos los tratamientos con la combinación del hongo con un insecticida. A los 105 DAT, el número de ninfas habían aumentado en todos los tratamientos, y ningún tratamiento había proporcionado un control efectivo. Los tratamientos con los mayores rendimientos hectárea fueron A1 (3×10 12 conidios ha −1 de M. a.+ 65 g de thiamethoxam) y M. anisopliae solo a la dosis recomendada de 3×10 12 conidios ha −1 de M. a. Nuestros resultados demuestran la eficacia de thiamethoxam y imidacloprido en combinación con M. anisopliae para el control de ninfas M. fimbriolata en caña de azúcar, pero mayores beneficio neto por hectárea se produjeron con la tasa más baja de la combinación de thiamethoxam que con cualquiera de las combinaciones de imidacloprid

    Observation of an Excited Bc+ State

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    Using pp collision data corresponding to an integrated luminosity of 8.5 fb-1 recorded by the LHCb experiment at center-of-mass energies of s=7, 8, and 13 TeV, the observation of an excited Bc+ state in the Bc+π+π- invariant-mass spectrum is reported. The observed peak has a mass of 6841.2±0.6(stat)±0.1(syst)±0.8(Bc+) MeV/c2, where the last uncertainty is due to the limited knowledge of the Bc+ mass. It is consistent with expectations of the Bc∗(2S31)+ state reconstructed without the low-energy photon from the Bc∗(1S31)+→Bc+γ decay following Bc∗(2S31)+→Bc∗(1S31)+π+π-. A second state is seen with a global (local) statistical significance of 2.2σ (3.2σ) and a mass of 6872.1±1.3(stat)±0.1(syst)±0.8(Bc+) MeV/c2, and is consistent with the Bc(2S10)+ state. These mass measurements are the most precise to date

    International conference on the healthy effect of virgin olive oil

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    Ageing represents a great concern in developed countries because the number of people involved and the pathologies related with it, like atherosclerosis, morbus Parkinson, Alzheime's disease, vascular dementia, cognitive decline, diabetes and cancer. Epidemiological studies suggest that a Mediterranean diet (which is rich in virgin olive oil) decreases the risk of cardiovascular disease. The Mediterranean diet, rich in virgin olive oil, improves the major risk factors for cardiovascular disease, such as the lipoprotein profile, blood pressure, glucose metabolism and antithrombotic profile. Endothelial function, inflammation and oxidative stress are also positively modulated. Some of these effects are attributed to minor components of virgin olive oil. Therefore, the definition of the Mediterranean diet should include virgin olive oil. Different observational studies conducted in humans have shown that the intake of monounsaturated fat may be protective against age-related cognitive decline and Alzheimer's disease. Microconstituents from virgin olive oil are bioavailable in humans and have shown antioxidant properties and capacity to improve endothelial function. Furthermore they are also able to modify the haemostasis, showing antithrombotic properties. In countries where the populations fulfilled a typical Mediterranean diet, such as Spain, Greece and Italy, where virgin olive oil is the principal source of fat, cancer incidence rates are lower than in northern European countries. The protective effect of virgin olive oil can be most important in the first decades of life, which suggests that the dietetic benefit of virgin olive oil intake should be initiated before puberty, and maintained through life. The more recent studies consistently support that the Mediterranean diet, based in virgin olive oil, is compatible with a healthier ageing and increased longevity. However, despite the significant advances of the recent years, the final proof about the specific mechanisms and contributing role of the different components of virgin olive oil to its beneficial effects requires further investigations. © 2005 Blackwell Publishing Ltd
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