Modelos de control quimioterapéutico contra Fasciola hepatica en ganado bovino en pastoreo en clima cálido húmedo

2 páginas.-- Trabajo presentado al XIII Congreso Latinoamericano de Parasitología ( La Habana, Cuba, 11 al 23 de Noviembre, 1997).La fasciolosis en bovinos en el estado de Veracruz, México, tiene una alta prevalencia, por lo que se considera una necesidad generar información sobre modelos de control. Con el objetivo de evaluar 3 modelos de tratamientos fasciolicidas aplicados de manera estratégica en base a las condiciones climatológicas locales, se emplearon 3 grupos de 23 vacunos cada uno, hembras cruces de cebú con suizo pardo, homogéneos en las cantidades de huevos de 5 g de heces. Se utilizó el triclabendazol a dosis de 12 mg/kg. El grupo 1 fue tratado en enero, el 2 en enero y junio, y el 3 en enero, junio y octubre. Cada 45 días se les practicaron exámenes coprológicos cuantitativos (hpg) por la técnica de sedimentación durante un año. Los bovinos se encontraban localizados en una finca situada en el municipio de Nautla, Estado de Veracruz. Se encontró en el grupo 1 la prevalencia al inicio de 100%, en los siguientes 5 muestreos fue de 21.7 a 91.3 % y en el resto de 100%, mientras que el x de hpg al inicio fue de 13.23.14 se redujo en 5 muestreos de 0.560.26 a 12.12.02 mientras que en 4 se incrementó de 14.63.87 a 21.1 3.06 con diferencia (P0.01) entre el primer muestreo y los siguientes. En el grupo 2 la prevalencia al inicio fue de 100%, posteriormente se redujo en 8 muestreos de 8.6% a 95.6%, mientras que el último muestreo fue de 100%, el x de hpg al inicio fue de 15.043.62 se redujo en 8 muestreos de 0.170.13 a 14.102.13 mientras que el penúltimo muestreo fue de 15.733.07 con diferencia entre el primer muestreo hasta el 8, pero sin diferencia con el 9 y el 10 (P0.01). En el grupo 3 la prevalencia al inicio fue de 100% en los siguientes muestreos se redujo de 15.07% a 94.4%, mientras el x de hpg al inicio fue de 13.132.24 disminuyó en los subsecuentes muestreos 0.270.13 a 11.554.56 se encontró que hubo diferencia entre el primer muestreo con todos los subsecuentes (P0.01). Al comparar entre grupos mediante la prueba de Kruskall-Wallis se encontró que hay diferencia (P0.01) del muestreo 8 al 10.Peer reviewe

Absorption and cutaneous deposition of yellow pigment in male and female broilers in response to different levels of xanthophylls from Tagetes erecta

To determine the saturation point of absorption and cutaneous deposition of yellow xanthophylls (XA) in broilers, two hundred and sixteen Ross 308 chickens (108 males and 108 females) were sorted by sex and randomly assigned to 6 dietary treatments containing 6 replications of 6 birds each. Treatments consisted of increasing levels of xanthophylls from Aztec marigold flower (Tagetes erecta) (65, 92, 119, 146, 173, and 200 ppm). Weight gain, feed consumption, and feed conversion were measuredweekly. Plasma pigment levels and skin yellowness in live birds were measured twice per week. Growth performance was analysed through ANOVA for a 6X2 factorial arrangement, where the first factor was the XA adding at six levels, and the second factor was sex at two levels. Pigment plasma concentration and skin yellowness were fitted into a multiple linear regression model. Results indicated that the highest levels of plasma xanthophylls and skin yellowness were found after 28 d of feeding. Skin yellowness increased by 2.24 b* for every d of xanthophylls consumption. In the females, skin yellowness was 1.35 b* higher than in the males. Increasing dietary xanthophylls by 10 ppm was reflected in 0.83 b* of increase in skin yellowness

What do epidemiological studies tell us about chronic kidney disease of undetermined cause in Meso-America? A systematic review and meta-analysis

Background: The aim of this systematic review is to examine the epidemiological knowledge and gaps in understanding of the potential causes of chronic kidney disease of undetermined cause (CKDu) in Meso-America. // Methods: A systematic literature search of epidemiological studies of CKDu was conducted in PubMed, Embase and Web of Science from January 2000 to January 2017. Study quality was assessed by adapting the tool from Higgins et al. for observational studies. Where applicable, the summary prevalence odds ratio (POR) and 95% confidence interval (CI) were calculated using a random effects model. // Results: Twenty-five epidemiological studies were included in the analysis of risk factors for CKDu. The quality assessment of each occupational and community study was medium. The PORs for CKDu were males versus females 2.42 (95% CI 1.76–3.08), family history of CKD (versus none) 1.84 (95% CI 1.37–2.30), high water intake (versus low) 1.61 (95% CI 1.01–2.21) and low altitude (versus highland) 2.09 (95% CI 1.00–3.17). There were no significant associations between CKDu and pesticide exposure (versus no) 1.17 (95% CI 0.87–1.46), alcohol consumption (versus no) 1.34 (95% CI 0.84–1.84), non-steroidal anti-inflammatory drugs (versus no) 0.99 (95% CI 0.60–1.39) and heat stress (versus no) 1.52 (95% CI −0.91 – 3.95). // Conclusion: Our meta-analysis showed positive associations for males (versus females) and family history of CKD, water intake, lowland altitude and CKDu. There were no significant associations with pesticide exposure, non-steroidal anti-inflammatory drugs intake, heat stress and alcohol consumption

Renal Morphology, Clinical Findings, and Progression Rate in Mesoamerican Nephropathy

BackgroundMesoamerican nephropathy (MeN) is a chronic kidney disease affecting rural inhabitants in Central America. We have previously described the renal morphology in 8 patients from El Salvador. To confirm the renal pathology, we have studied kidney biopsies from patients with MeN in Nicaragua. Follow-up urine and blood samples from both biopsy studies were collected to investigate the natural history

Análisis de integridad de un elemento estructural de acero colado utilizado en un puente atirantado

Se presenta la evaluación de la integridad estructural, mediante diagramas de fallo, de 112 anclajes fabricados con acero colado y utilizados en un puente atirantado. Uno de los anclajes había sufrido un fallo y en multitud de ellos se detectaron defectos no planos. Para el desarrollo de los diagramas de evaluación se consideró una fisura elíptica superficial con tres parámetros geométricos distintos. Además, una fisura elíptica embebida y una fisura elíptica superficial, éstas dos últimas de acuerdo a los defectos encontrados en el material. Se utilizaron dos condiciones de carga: incremento de flujo vehicular simulado a 30 años con un incremento anualizado del 6% y las cargas que se producen por el peso de 4 tractocamiones que están a la mitad del puente. Se determinaron las propiedades en tracción del acero de acuerdo a la norma ASTM E- 8 y la tenacidad a la fractura se obtuvo según el procedimiento de la norma ASTM E-1820. Cuando se aplica la carga de servicio simulado a 30 años, los diagramas de fallo muestran que las diferentes tipos de grieta analizados caen en la zona segura del diagrama, y en una condición insegura con las cargas de los 4 tractocamiones. Se concluye que el componente estructural estudiado podrá operar de una manera segura siempre y cuando las cargas aplicadas no alcancen las 974 ton producidas por el peso de los 4 tractocamiones

Sexual propagation of Abies religiosa (Kunth) Cham, by immersion in water at different temperatures and periods

Objective: To increase the percentage of germination in Abies religiosa by immersion in water at different temperatures and times that the seeds will be soaked. Design/methodology/approach: A completely randomized factorial experiment was carried oud with five temperatures (10, Ta, 30, 40 and 50 °C) and 13 times expressed in seconds (10, 20, 40, 60, 600, 1200, 1800, 2400, 3000, 3600, 7200, 14400 and 2160) with a total of 65 treatments and 30 replications of each treatment. The seed were immersed in water at different temperatures and times corresponded to each treatment in order to obtain the best treatment that generated the highest percentage. Results: The best pre-germinative treatment that generated the highest germination percentage was the combination of temperature of 40 °C and a time of 7200s, obtaining 73% germination, and 14% germination as the lowest percentage in the combinations (10 °C x 20s and 10 °C x 40s), generating 26 treatments with percentages higher than 50% germination, registering a peak value of 8.56 and 11.7 days to reach the peak value. Limitations on study/implications: In the experiment, it was important to maintain the different temperatures constant, being those of longer time, lower temperature and higher temperature the most difficult to control and maintain Findings/conclusions: Abies religiosa is able to tolerate and generate acceptable germination percentages with the highest temperature used (50 °C), being one of the best temperatures, which was supposed to generate low germination percentages. Keywords: Germination, Temperature, Time, Peak valueObjective: To increase the germination percentage of Abies religiosa by immersion in water with different temperatures and periods.Design/Methodology/Approach: A completely randomized factorial experiment was carried out with five temperatures (10, Room temperature (Rt), 30, 40, and 50°C) and 13 periods expressed in seconds (10, 20, 40, 60, 600, 1200, 1800, 2400, 3000, 3600, 7200, 14400, and 21600), with a total of 65 treatments and 30 repetitions per treatment. The seeds were dipped in water with the temperatures and periods of each treatment to obtain the highest germination percentage.Results: The best pre-germination treatment (73% germination) was obtained with the combination of 40 °C and 7,200 s. Meanwhile, the treatments with the lowest percentage (14%) were the combinations 10 °C × 20 s and 10 °C × 40 s. Twenty-six treatments recorded a >50% germination, reaching a peak value of 8.56 at 11.7days. Study Limitations/Implications: Keeping the water temperature and theimmersion period constant during the experiment was more difficult in the longer treatments, with the lowest and highest temperatures.Findings/Conclusions: Abies religiosa registers acceptable germination percentages with the highest temperature (50 °C)

Electrodeposited lead dioxide coatings

Lead dioxide coatings on inert substrates such as titanium and carbon now offer new opportunities for a material known for 150 years. It is now recognised that electrodeposition allows the preparation of stable coatings with different phase structures and a wide range of surface morphologies. In addition, substantial modification to the physical properties and catalytic activities of the coatings are possible through doping and the fabrication of nanostructured deposits or composites. In addition to applications as a cheap anode material in electrochemical technology, lead dioxide coatings provide unique possibilities for probing the dependence of catalytic activity on layer composition and structure (critical review, 256 references)

Effects of temperature on thick branes and the fermion (quasi-)localization

Following Campos's work [Phys. Rev. Lett. 88, 141602 (2002)], we investigate the effects of temperature on flat, de Sitter (dS), and anti-de Following Campos's work [Phys. Rev. Lett. \textbf{88}, 141602 (2002)], we investigate the effects of temperature on flat, de Sitter (dS), and anti-de Sitter (AdS) thick branes in five-dimensional (5D) warped spacetime, and on the fermion (quasi-)localization. First, in the case of flat brane, when the critical temperature reaches, the solution of the background scalar field and the warp factor is not unique. So the thickness of the flat thick brane is uncertain at the critical value of the temperature parameter, which is found to be lower than the one in flat 5D spacetime. The mass spectra of the fermion Kaluza-Klein (KK) modes are continuous, and there is a series of fermion resonances. The number and lifetime of the resonances are finite and increase with the temperature parameter, but the mass of the resonances decreases with the temperature parameter. Second, in the case of dS brane, we do not find such a critical value of the temperature parameter. The mass spectra of the fermion KK modes are also continuous, and there is a series of fermion resonances. The effects of temperature on resonance number, lifetime, and mass are the same with the case of flat brane. Last, in the case of AdS brane, {the critical value of the temperature parameter can less or greater than the one in the flat 5D spacetime.} The spectra of fermion KK modes are discrete, and the mass of fermion KK modes does not decrease monotonically with increasing temperature parameter.Comment: 24 pages, 15 figures, published versio

An NLO QCD analysis of inclusive cross-section and jet-production data from the ZEUS experiment

The ZEUS inclusive differential cross-section data from HERA, for charged and neutral current processes taken with e+ and e- beams, together with differential cross-section data on inclusive jet production in e+ p scattering and dijet production in \gamma p scattering, have been used in a new NLO QCD analysis to extract the parton distribution functions of the proton. The input of jet data constrains the gluon and allows an accurate extraction of \alpha_s(M_Z) at NLO; \alpha_s(M_Z) = 0.1183 \pm 0.0028(exp.) \pm 0.0008(model) An additional uncertainty from the choice of scales is estimated as \pm 0.005. This is the first extraction of \alpha_s(M_Z) from HERA data alone.Comment: 37 pages, 14 figures, to be submitted to EPJC. PDFs available at http://durpdg.dur.ac.uk/hepdata in LHAPDFv

Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal