1,938 research outputs found

    XXIII International Conference on Spectral Line Shapes

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    Producción CientíficaDoppler free two-photon optogalvanic spectroscopy has been applied to measure the electric field strength in the cathode fall region of a hollow cathode discharge, via the Stark splitting of the 2S level of atomic hydrogen. Important improvements in the experimental arrangement and in our understanding of the discharge, have allowed us to measure accurately the dependence of the electric field with different parameters like the cathode material (stainless steel and tungsten), geometry (10 and 15 mm inner diameter) and the buffer gas. The study is done for different pressures and currents. The first results seem to reveal different behaviour in the electric field, depending on the material and geometry of the cathode and the discharge conditions.Ministerio de Economía, Industria y Competitividad (grants ENE2012- 35902 and BES-2013-063248

    A Variational Approach for Designing Infinite Impulse Response Filters With Time-Varying Parameters

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    Filter design with short transient state is a problem encountered in many fields of circuits, systems, and signal processing. In this paper, a novel low-pass filter design technique with time-varying parameters is introduced in order to minimize the rise-time parameter. Through the use of calculus of variations a method is developed to obtain the optimal closed-form expression for adjusting the parameters. In this context, two cases are addressed: the ideal case in which infinite bandwidth is required and a solution of finite bandwidth. The latter is obtained by means of a proper constraint formulation in the frequency domain. The proposed filter achieves the shortest rise time and allows better preservation of the edge shape in comparison with other existing filtering methods. The analysis, synthesis, and performance of the proposed system are discussed and illustrated with the aid of simulations

    La fauna nativa de México en riesgo y la NOM-059: ¿Están todos los que son y son todos los que están?

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    The Norma Oficial Mexicana 059 (NOM-059) is the Mexican legal instrument that identifies species or populations at risk throug the use of the Método de Evaluación de Riesgo de Extinción de Especies Silvestres de México (MER). From its first promulgation in 1994, the NOM-059 has been used as a reference to assess the conservation status, and as a tool on national environmental policies; however, it has been questioned for the lack of scientific criteria. We assess the relevance of the NOM-059 as a tool to assess the conservation status of Mexican native species by utilizing the mammals as a case study. More than 40% of native mammals are included in the list, though only 10% of the listed species had been evaluated with the MER, and have technical support to justify their inclusion. In most cases, criteria used to determine the species inclusion are unknown, in the other cases the criteria are contradictory with the objectives and methods stablished in the NOM-059. Non-endemic mammals are overrepresented in the list, while the extinction risk of the endemic mammals is underestimated.The evidence shows that in its current form the NOM-059 it is not an adequate tool to assess the species conservation status. Finally, we list a series of recommendations that would improve NOM-059 and strengthen conservation efforts in Mexico. Resumen. La Norma Oficial Mexicana 059 (NOM-059) es el instrumento normativo que identifica las especies o poblaciones de México en riesgo mediante la aplicación del Método de Evaluación de Riesgo de Extinción de Especies Silvestres de México (MER). Desde su primera publicación en 1994 la Norma ha sido usada como referencia para evaluar el estado de conservación y como herramienta en las políticas ambientales nacionales; sin embargo, ha sido fuertemente cuestionada por la aparente falta de criterios científicos. El objetivo de este trabajo fue evaluar la pertinencia del uso de la NOM-059 como referencia del estado de conservación de las especies nativas de México utilizando a los mamíferos como caso de estudio. Más del 40% de los mamíferos nativos de México están incluidos, pero solo el 10% del total de especies listadas se han evaluado con el MER; solo estas especies cuentan con soporte técnico que justifique su inclusión. En la mayoría de los casos los criterios empleados para determinar la inclusión se desconocen, pero en algunos casos son incluso contradictorios a los objetivos y metodología establecidos en la misma Norma. Los resultados sugieren que los mamíferos no endémicos están sobrerrepresentados en la NOM-059, mientras que el riesgo de extinción de los mamíferos endémicos está subestimado. La evidencia pone de manifiesto que en su forma actual la NOM-059 no es la herramienta adecuada para evaluar el estado de conservación. Finalmente, presentamos una serie de  recomendaciones que consideramos contribuyen a mejorar la NOM-059 y así fortalecer los esfuerzos de conservación del país.

    Tsukamurella pulmonis bloodstream infection identified by secA1 gene sequencing

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    Recurrent bloodstream infections caused by a Gram-positive bacterium affected an immunocompromised child. Tsukamurella pulmonis was the microorganism identified by secA1 gene sequencing. Antibiotic treatment in combination with removal of the subcutaneous port healed the patient

    Minor compounds from virgin olive oil attenuate LPS-induced inflammation via visfatin-related gene modulation on primary human monocytes

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    We have analyzed the effects of minor compounds found in the unsaponifiable fraction (UF) and in the phenolic fraction (PF) of virgin olive oil (VOO) on LPS-induced inflammatory response via visfatin modulation in human monocytes. For this purpose, monocytes were incubated with UF and PF at different concentrations and the pro-inflammatory stimulus LPS for 24 hr; squalene (SQ) and hydroxytyrosol (HTyr), the main components in UF and PF, respectively, were also used. The relative expression of both pro-inflammatory and anti-inflammatory genes, as well as other genes related to the NAD+-biosynthetic pathway was evaluated by RT-qPCR; and the secretion of some of these markers was assessed by ELISA procedures. We found that UF, SQ, PF, and HTyr prevented from LPS-induced dysfunctional gene expression and secretion via visfatin-related gene modulation in human monocytes. These findings unveil a potential beneficial role for minor compounds of VOO in the prevention of inflammatory-disorders. Practical application: In this project, potential health benefits of VOO micronutrients (unsaponifiable and phenolic compounds) were confirmed through anti-inflammatory assays. Our results reveal new interesting researching goals concerning nutrition by considering the role of bioactive VOO compounds in the prevention and progress of diseases related to inflammation

    Microscopia de campo oscuro. Una opción en el diagnóstico de la sífilis

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    Introduction: The diagnosis of syphilis by darkfield microscopy, also known as ultra-microscopy, can get ahead in the primary stage up to two weeks compared to a serodiagnostic immunoassay by serological test for syphilis and rapid plasma reagin test, which can result non-reactive. The analysis of the results of the last seven years was the reason for conducting this work. Objective: To characterize the dark field microscopy as an option in the diagnosis of syphilis. Methods: a descriptive, longitudinal and retrospective study was conducted from January 2004 to December 2010. The population consisted of 496 patients who met the inclusion criteria. Results: there were 496 samples of which 354 were negative 71.3%, the overall results of the first and second semesters do not provide differences of epidemiological value. Positive diagnosis reached 28.6%. Conclusions: dark field microscopy allows confirming the presumptive diagnosis at the primary stage, when nontreponemal serological techniques are in an open window period (not reactive). The results show that one in three patients was diagnosed by this technique, leading to the begining of therapy and the implementation of the epidemiological containment of transmission. The negative darkfield does not exclude the possibility of syphilis, the knowledge of the requirements and limitations are essential for a successful diagnosis.Introducción: el diagnóstico de la sífilis por microscopia de campo oscuro, también conocido como ultramicroscopia, puede adelantarse en la etapa primaria hasta dos semanas al inmuno serodiagnóstico por la prueba serológica para la sífilis o la prueba de reagina plasmática rápida, que pueden dar no reactivas; el análisis de los resultados de los últimos siete años fue el motivo de la realización de este trabajo. Objetivo: caracterizar la microscopia de campo oscuro como una opción en el diagnóstico de la sífilis. Método: se realizó un trabajo descriptivo, longitudinal y retrospectivo de enero de 2004-diciembre de 2010, la población estuvo constituida por 496 pacientes que cumplieron los criterios de inclusión. Resultados: se realizaron 496 muestras de las que 354 fueron negativas (71,3%), los resultados totales de los primeros y segundos semestres no ofrecen diferencias de valor epidemiológico y el diagnóstico positivo alcanzó un 28,6%. Conclusiones: la microscopia de campo oscuro permite confirmar el diagnóstico presuntivo en la etapa primaria, donde las técnicas serológicas no reponémicas se encuentran en un franco período de ventana (no reactivas). El resultado obtenido permite afirmar que uno de cada tres pacientes fue diagnosticado por esta técnica, lo que propició  comenzar el tratamiento y realizar la contención epidemiológica de la transmisión. El campo oscuro negativo no excluye la posibilidad de sífilis; el conocimiento de los requisitos y las limitaciones son indispensables para un diagnóstico exitoso

    The effects of exogenous fatty acids and niacin on human monocyte-macrophage plasticity

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    Scope: Macrophage plasticity allows adapting to different environments, having a dual activity in inflammatory-related diseases. Our hypothesis is that the type of dietary fatty acids into human postprandial triglyceride-rich lipoproteins (TRLs), alone or in combination with niacin (vitamin B3), could modulate the plasticity of monocytes-macrophages. Methods and results: We isolated TRLs at the postprandial peak from blood samples of healthy volunteers after the ingestion of a meal rich in saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) or MUFAs plus omega-3 long-chain polyunsaturated fatty acids (LCPUFAs). Autologous monocytes isolated at fasting were first induced to differentiate into naïve macrophages. We observed that postprandial TRL-MUFAs, particularly in combination with niacin, enhance competence to monocytes to differentiate and polarise into M2 macrophages. Postprandial TRL-SFAs made polarised macrophages prone to an M1 phenotype. In contrast to dietary SFAs, dietary MUFAs in the meals plus immediate-release niacin primed circulating monocytes for a reduced postprandial pro-inflammatory profile. Conclusion: Our study underlines a role of postprandial TRLs as a metabolic entity in regulating the plasticity of the monocyte-macrophage lineage and also brings an understanding of the mechanisms by which dietary fatty acids are environmental factors fostering the innate immune responsiveness in humans.Ministerio de Ciencia e Innovación AGL2011- 2900

    gh/igf axis gene expression profile in developing atlantic bluefin tuna (Thunnus thynnus).

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    Atlantic bluefin tuna (ABFT), Thunnus thynnus (Linnaeus, 1758), is a large migratory oceanic top predator, considered as an important worldwide fishery source and a key species in pelagic ecosystems. Survival during the early life stages is crucial for future recruitment success, with larval growth being a determining process. Fish growth and development are mainly controlled by the GH/IGF axis, being involved in skeletal and soft tissue growth, as well as in immune function, appetite control, behavior (including foraging, aggression, and predator avoidance). To characterize the ontogenetic development profile of the GH/IGF axis at the level of gene expression, an ABFT larval rearing experiment (under controlled feeding conditions) was performed in the aquaculture facilities of the Spanish Institute of Oceanography (IEO), in Mazarrón during June 2019. Eggs and larvae from 3 replicates were collected regularly every 2-3 days from 0 until 30 days post-hatching (dph). In a total of 14 sampling points (n = 6-12 larvae) along the ontogeny, growth hormone (gh) and two forms of insulin growth factor (igf1 and igf2) were analyzed by real-time RT-PCR. A sigmoidal gh expression profile was observed, with higher values at 5 and 23 (maximum) dph, and lower values at 0 (minimum), 12 and 30 dph. Nevertheless, igf1 and igf2 showed a gradual increase from early days, also with lower values at 0 and 12 dph, but with maximum levels at 30 dph. Results are discussed considering growing rates and transition from larvae to juvenile, underlining the importance of gh/ igf axis during the ABFT early development and growth

    GH/IGF AXIS GENE EXPRESSION PROFILE IN DEVELOPING ATLANTIC BLUEFIN TUNA (Thunnus thynnus)

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    Atlantic bluefin tuna (ABFT), Thunnus thynnus (Linnaeus, 1758), is a large migratory oceanic top predator, considered as an important worldwide fishery source and a key species in pelagic ecosystems. Survival during the early life stages is crucial for future recruitment success, with larval growth being a determining process. Fish growth and development are mainly controlled by the GH/IGF axis, being involved in skeletal and soft tissue growth, as well as in immune function, appetite control, behavior (including foraging, aggression, and predator avoidance). To characterize the ontogenetic development profile of the GH/IGF axis at the level of gene expression, an ABFT larval rearing experiment (under controlled feeding conditions) was performed in the aquaculture facilities of the Spanish Institute of Oceanography (IEO), in Mazarrón during June 2019. Eggs and larvae from 3 replicates were collected regularly every 2-3 days from 0 until 30 days post-hatching (dph). In a total of 14 sampling points (n = 6-12 larvae) along the ontogeny, growth hormone (gh) and two forms of insulin growth factor (igf1 and igf2) were analyzed by real-time RT-PCR. A sigmoidal gh expression profile was observed, with higher values at 5 and 23 (maximum) dph, and lower values at 0 (minimum), 12 and 30 dph. Nevertheless, igf1 and igf2 showed a gradual increase from early days, also with lower values at 0 and 12 dph, but with maximum levels at 30 dph. Results are discussed considering growing rates and transition from larvae to juvenile, underlining the importance of gh/ igf axis during the ABFT early development and growth
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