1,659 research outputs found

    A catalog of warps in spiral and lenticular galaxies in the Southern hemisphere

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    A catalog of optical warps of galaxies is presented. This can be considered complementary to that reported by Sanchez-Saavedra et al., with 42 galaxies in the northern hemisphere, and to that by Reshetnikov & Combes, with 60 optical warps. The limits of the present catalog are: logr25 > 0.60, B_{t} < 14.5, delta(2000) < 0, -2.5 < t < 7. Therefore, lenticular galaxies have also been considered. This catalog lists 150 warped galaxies out of a sample of 276 edge-on galaxies and covers the whole southern hemisphere, except the Avoidance Zone. It is therefore very suitable for statistical studies of warps. It also provides a source guide for detailed particular observations. We confirm the large frequency of warped spirals: nearly all galaxies are warped. The frequency and warp angle do not present important differences for the different types of spirals. However, no lenticular warped galaxy has been found within the specified limits. This finding constitutes an important restriction for theoretical models.Comment: 12 pages, 6 figures, to be published in Astronomy and Astrophysic

    Antibacterial activity in three Chaetoceros microalgae species cultures by using antibiotics

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    Diatoms, such as Chaetoceros, grow in a mutualistic relationship with bacteria. However, in some cases, it is necessary to grow them in bacteria-free cultures. To reduce bacterial load, antibiotics are used, and on certain occasions it is necessary to use a mixture with more than one antibiotic. This work aimed to obtain a quick and effective protocol to reduce the bacterial load and evaluate the response of three Chaetoceros species with aquacultural importance. Single and mix antibiotics were used. Microalgal and bacterial growth was measured. The growth parameters for diatoms showed that the significantly highest cell concentration was for C. muelleri (3.15 x106 cells mL-1) and the lowest values to C. calcitrans (2.98 x106 cells mL-1). The significantly highest growth rate was for C. calcitrans (0.77 divisions per day), and the lowest values for Chaetoceros sp. (0.60 divisions per day). The growth parameters for heterotrophic bacteria showed that the significantly highest bacterial load was for Chaetoceros sp. (19.16 x106 CFU (Colony-Forming Units) mL-1) and the lowest values were for C. calcitrans (12.23 x106 CFU mL-1). The growth rate of the heterotrophic bacteria present in Chaetoceros cultures was similar among the three studied species. Streptomycin® and sulfate G41® produced a partial reduction of bacterial load. The most effective treatment for all three species was the use of an antibiotic mix composed of ampicillin® (250 μg mL-1), kanamycin® (200 μg mL-1), neomycin® (50 μg mL-1), and streptomycin® (100 μg mL-1) for three days. The mix prepared with the highest antibiotic concentration produced a reduction of bacteria (100%) for three days; however, it also induced a significant reduction of the growth of the three Chaetoceros species

    Kinetic studies of sodium and metforminium decavanadates decomposition and in vitro cytotoxicity and insulin-like activity

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    The kinetics of the decomposition of 0.5 and 1.0 mM sodium decavanadate (NaDeca) and metforminium decavanadate (MetfDeca) solutions were studied by51V NMR in Dulbecco’s modified Eagle’s medium (DMEM) medium (pH 7.4) at 25◦C. The results showed that decomposition products are orthovanadate [H2VO4]− (V1) and metavanadate species like [H2V2O7]2− (V2), [V4O12]4− (V4) and [V5O15]5− (V5) for both compounds. The calculated half-life times of the decomposition reaction were 9 and 11 h for NaDeca and MetfDeca, respectively, at 1 mM concentration. The hydrolysis products that presented the highest rate constants were V1 and V4 for both compounds. Cytotoxic activity studies using non-tumorigenic HEK293 cell line and human liver cancer HEPG2 cells showed that decavanadates compounds exhibit selectivity action toward HEPG2 cells after 24 h. The effect of vanadium compounds (8–30 µM concentration) on the protein expression of AKT and AMPK were investigated in HEPG2 cell lines, showing that NaDeca and MetfDeca compounds exhibit a dose-dependence increase in phosphorylated AKT. Additionally, NaDeca at 30 µM concentration stimulated the glucose cell uptake moderately (62%) in 3T3-L1 adipocytes. Finally, an insulin release assay in βTC-6 cells (30 µM concentration) showed that sodium orthovanadate (MetV) and MetfDeca enhanced insulin release by 0.7 and 1-fold, respectively.Fil: Silva Nolasco, Aniela M.. Universidad Juárez Autónoma de Tabasco; México. Instituto Nacional de Pediatría; MéxicoFil: Camacho, Luz. Instituto Nacional de Pediatría; MéxicoFil: Saavedra Díaz, Rafael Omar. Universidad Juárez Autónoma de Tabasco; MéxicoFil: Hernández Abreu, Oswaldo. Universidad Juárez Autónoma de Tabasco; MéxicoFil: Leon, Ignacio Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; ArgentinaFil: Sánchez Lombardo, Irma. Universidad Juárez Autónoma de Tabasco; Méxic

    Aplicación de un programa de aquaeróbic de muy corta duración (4 semanas) para la mejora de la condición física saludable en mujeres jóvenes sanas

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    El objetivo de este estudio fue conocer la influencia sobre la condición física saludable de un programa de aquaerobic de muy corta duración en mujeres jóvenes sanas. Participaron en este trabajo 22 mujeres sin patologías aparentes (20,560,98 años), estudiantes de la licenciatura de Ciencias de la Actividad Física y el Deporte, que no practicaban ningún deporte. Los sujetos llevaron a cabo un programa de acondicionamiento físico en el medio acuático basado en el aquaerobic de muy corta duración (8 sesiones de 30 minutos). Se valoró la condición física saludable, inmediatamente antes y después de la actividad. Los resultados muestran una disminución del peso graso estimado y una mejora de la flexibilidad de tronco, fuerza de prensión manual, fuerza-resistencia abdominal, equilibrio y potencia aeróbica máxima estimada. Las conclusiones del presente trabajo fueron: a) un programa de acondicionamiento físico de muy corta duración en el medio acuático se muestra eficaz en la reducción de la masa grasa corporal y b) mediante dicho programa se consiguen mejoras en la mayoría de los parámetros de la condición física saludable en mujeres jóvenes sanas, en especial en los relacionados con la fuerza, la flexibilidad y el equilibrio

    Ghrelin induces clock gene expression in the liver of goldfish in vitro via protein kinase C and protein kinase A pathways

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    The liver is the most important link between the circadian system and metabolism. As a food-entrainable oscillator, the hepatic clock needs to be entrained by food-related signals. The objective of the present study was to investigate the possible role of ghrelin (an orexigenic peptide mainly synthesized in the gastrointestinal tract) as an endogenous synchronizer of the liver oscillator in teleosts. To achieve this aim, we first examined the presence of ghrelin receptors in the liver of goldfish. Then, the ghrelin regulation of clock gene expression in the goldfish liver was studied. Finally, the possible involvement of the phospholipase C/protein kinase C (PLC/PKC) and adenylate cyclase/protein kinase A (AC/PKA) intracellular signalling pathways was investigated. Ghrelin receptor transcripts, ghs-r1a, are present in the majority of goldfish hepatic cells. Ghrelin induced the mRNA expression of the positive (gbmal1a, gclock1a) and negative (gper genes) elements of the main loop of the molecular clock machinery, as well as grev-erbα (auxiliary loop) in cultured liver. These effects were blocked, at least in part, by a ghrelin antagonist. Incubation of liver with a PLC inhibitor (U73122), a PKC activator (phorbol 12-myristate 13-acetate) and a PKC inhibitor (chelerythrine chloride) demonstrated that the PLC/PKC pathway mediates such ghrelin actions. Experiments with an AC activator (forskolin) and a PKA inhibitor (H89) showed that grev-erbα regulation could be due to activation of PKA. Taken together, the present results show for the first time in vertebrates a direct action of ghrelin on hepatic clock genes and support a role for this hormone as a temporal messenger in the entrainment of liver circadian functions

    Emotional Intelligence in Times of Covid-19: a Comparative Study in Peruvian Universities

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    Objective:The aim of the study was to compare emotional intelligence in Peruvian university students from public and private universities.Theoretical framework: In higher education, emotionally intelligent students have the ability to interact appropriately with others, achieve good academic results, and reach personal and professional goals.Method: The methodology was descriptive-comparative, the sample consisted of 838 university students of both sexes from public (471) and private (364) universities belonging to the coast, highlands and jungle regions of Peru. A sociodemographic form created for the study and the emotional intelligence scale (TMMS-24) were used as measurement instruments.Results and conclusion:The results showed that university students over 30 years of age, women, those from the highlands and those who worked had high levels of emotional intelligence.Implications of the research:It is necessary for university institutions to reorganize their academic conditions and provide the necessary inputs to apply socioemotional strategies to students. Researchers linked to the lines of research on emotional intelligence should develop predictive studies to know which factors may be predicting adequate or inadequate emotional intelligence in university students.Originality:This study demonstrates that it is essential to attend to and provide emotional intelligence tools to those students whodo not have the necessary resources to face different situations in the face of the COVID-19 pandemic and contributes to the training of educators, especially environmental educators in crisis contexts

    An Ensemble-based Machine Learning Model for Investigating Children Interaction with Robots in Childhood Education

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    "Investing in children's well-being and supporting high-quality pre-school education is a significant component of its promotion (ECE). All children have the right to participate. ECE teachers' thoughts about children's participation were examined to see if they were linked to children's perceptions of their participation. On the other hand, current studies focus on a single categorization method with lower overall accuracy. The findings of this study provided the basis for the development of an ensemble machine learning (ML) approach for measuring the participation of children with learning disabilities in educational situations that were specifically developed for them. Visual and auditory data are collected and analyzed to determine whether or not the youngster is engaged during the robot-child interaction in this manner. It is proposed that an ensemble ML technique (Enhanced Deep Neural Network (EDNN), Modified Extreme Gradient Boost Classifier, and Logistic Regression) be used to judge whether or not a youngster is actively engaged in the learning process. Children's participation in ECE courses depends on both the quantitative and qualitative characteristics of the classroom, according to this research.

    Dynamic rheological comparison of silicones for podiatry applications

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    Manuscrito aceptado[Abstract]: This work shows an effective methodology to evaluate the dynamic viscoelastic behavior of silicones for application in podiatry. The aim is to characterize, compare their viscoelastic properties according to the dynamic stresses they can be presumably subjected when used in podiatry orthotic applications. These results provide a deeper insight which extends the previous creep-recovery results to the world of dynamic stresses developed in physical activity. In this context, it shoulod be taken into account that an orthoses can subjected to a set of static and dynamic shear and compressive forces.Xunta de Galicia; ED431C-2016-015Xunta de Galicia; ED431G/01This research has been supported by the Spanish Ministry of Science and Innovation, MINECO grants MTM2014-52876-R and MTM2017-82724-R, and by the Xunta de Galicia (Grupos de Referencia Competitiva ED431C-2016-015 and Centro Singular de Investigación de Galicia ED431G/01), all of them through the ERD

    La recuperación mutua en personas con trastornos psicológicos o diversidad funcional a través de la práctica creativa

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    In this paper we introduce the concept of “mutual recovery” and we propose creative practices as efficient recovery tools people with both mental health problems as some sort of functional diversity. Compared with the traditional concept of “art therapy” we propose the concept of “creative practice” as more consistent with the model of “mutual recovery.” To do this, we first make a brief critical review of the relationship between art and madness. Next, we present the related concepts of “recovery” and “mutual recovery” in the context of what has become known as the “health humanities”. Finally, we describe two creative practices currently being tested in Spain in the context of the a international research project about mutual recovery:Creative workshops with people with serious mental illness at the Museum of Contemporary Art of Seville and the theater group of people with diverse functionality with the Down Syndrome Association of Seville.En el presente artículo introducimos el concepto de “recuperación mutua” y proponemos las prácticas creativas como herramientas eficientesde recuperación de personas tanto con problemas de salud mental como con algún tipo de diversidad funcional. Frente al concepto clásico de “arte-terapia” nosotros proponemos el concepto de “práctica creativa” como más compatible con el modelo de “recuperación mutua”. Para ello, en primer lugar realizamos un breve repaso crítico a la relación del arte con la locura. Seguidamente, presentamos los conceptos hermanos de “recuperación” y “recuperación mutua” en el marco de lo que se ha venido a denominar las “health humanities”. Para finalizar, describimos dos prácticas creativas que en la actualidad están siendo evaluadas en España en el contexto de un proyecto de investigacióninternacional en recuperación mutua: Los seminarios creativos con personas con trastorno mental grave en el Museo de Arte Contemporáneo de Sevilla y el grupo de teatro con personas con diversidad funcional de la Asociación Síndrome de Down-Sevill
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