8,273 research outputs found

    First data on testate amoebae in speleothems of caves in igneous rocks

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    [Abstract] The testate amoebae form part of the habitual troglobios in caves developed in igneous rocks (plutonic and volcanic) where the little light, the persistence of humidity, the availability of silica and organic matter allow these protozoa to develop their biological cycle. This work presents a first inventory of species of amoebae testate identified in caves in igneous rocks from different parts of the World

    Exploring discourse ethics for tourism transformation

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    The \u27critical turn\u27 in tourism is defined as a research perspective that explores social transformation in and through tourism by facing the negative impact of strategic-instrumental rationality on this activity. This work explores the features of discourse ethics that may normatively support tourism transformation, a gap that has not been thoroughly discussed in tourism research. For this purpose, the study combines the use of critical and ethical theory with an analysis of discourse ethics in tourism literature to demonstrate that the use of Habermasian discourse ethics needs to be complemented with the Apelian approach. Through these steps the work reveals the theoretical bases of discourse ethics to discuss whether understandings between stakeholders guided by strategic-instrumental rationality can be reached not only in the political sphere —Habermas—, but also in the ethical field —Apel

    On the level density of spin chains of Haldane--Shastry type

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    We provide a rigorous proof of the fact that the level density of all su(m) spin chains of Haldane-Shastry type associated with the A_{N-1} root system approaches a Gaussian distribution as the number of spins N tends to infinity. Our approach is based on the study of the large N limit of the characteristic function of the level density, using the description of the spectrum in terms of motifs and the asymptotic behavior of the dispersion relation.Comment: 6 pages, revte

    Four dimensional Lie symmetry algebras and fourth order ordinary differential equations

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    Realizations of four dimensional Lie algebras as vector fields in the plane are explicitly constructed. Fourth order ordinary differential equations which admit such Lie symmetry algebras are derived. The route to their integration is described.Comment: 12 page

    Proximal, Microbiological and Nutritional Characterization in Chinese Potato Flour of the White Variety Colocasia Esculenta for Application in Functional Foods

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    The study presents a qualitative-quantitative scope through descriptive statistics for the variables studied with its analyses, with the objective of performing physical, proximal, microbiological and contained characterization of amino acids in Chinese potato flour of the white variety Colocasia esculenta for its application in functional foods. By obtaining the flour, the proximal percentages are evaluated; moisture 9.01%, ash 2.24 ± 0.15% protein 2.02 ± 0.02% fiber 4.25 ± 0.26% and fat 0.43 ± 0.15%. Additionally, the physical-chemical analyses carried out on the flour obtain a pH of 6.66 ± 0.10% acidity (oxalic) 2.24 ± 0.00% Brix degrees 2 ± 0.50%. The nutritional values reported in the Chinese potato flour of the white variety lies mainly in its content of Methionine with a value of 21.15%, Alanine with 10.43%, Isoleucine with 8.08%, Threonine with 7.41%, Histidine with 3.65% and lysine with 3.10%. Finally, the microbiological analysis of the product is determined, concluding that they are within the parameters established in wheat flours with the INEN 616: 2006 standard; thus it is considered of good quality, suitable for human consumption and consequently, for use in the food industry. Therefore, it can be used as functional food or be transformed through the use of different techniques, thus being an important plant genetic resource to improve the nutritional quality of food, productivity, food health, as well as the protection and prevention of diseases in areas of the equator with high levels of malnutrition. Keywords: characterization, nutritional food, Chinese potato, industrialization, flour. Resumen El estudio presenta un alcance cualitativo-cuantitativo mediante la estadística descriptiva para las variables estudiadas con sus respectivos análisis y el objetivo de realizar la caracterización física, proximal, microbiológica y contenida de aminoácidos en harina de papa China de la variedad blanca Colocasia esculenta para su aplicación en alimentos funcionales. Mediante la obtención de la harina se evalúa los porcentajes proximales; humedad 9,01%, cenizas 2,24 ± 0,15% proteína 2,02 ± 0,02% fibra 4,25 ± 0,26% y grasa 0,43 ± 0.15%. Además, los análisis físico-químicos realizados en la harina se obtiene un pH de 6,66 ± 0,10% acidez (oxálico) 2,24 ± 0,00% grados Brix 2 ± 0,50%. Los valores nutricionales reportados en la harina de papa China de la variedad blanca radica principalmente en su contenido de Metionina con un valor de 21,15%, Alanina 10,43%, Isoleucina 8,08%, Treonina 7,41%, Histidina 3,65% y lisina con el 3,10%. Finalmente, se determina el análisis microbiológico del producto concluyendo que se encuentran dentro de los parámetros establecidos en harinas de trigo con la norma INEN 616:2006 de este modo se considera de buena calidad, apta para el consumo humano y consecutivamente empleada en industria alimentaria. Por lo que, puede ser utilizado como alimento funcional o ser trasformado mediante la utilización de distintas técnicas siendo así un importante recurso fitogenético para mejorar la calidad nutricional de los alimentos, la productividad, la 171 sanidad alimentaria, así como la protección y prevención de enfermedades en zonas del ecuador con altos niveles de desnutrición. Palabras clave: caracterización, alimento nutricional, papa China, industrialización, harina

    Desarrollo y validación de la escala de relajación-mindfulness para adolescentes (EREMIND-A)

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    Indexación: Scopus.Background: The aim of this investigation was to validate the Relaxation- Mindfulness Scale for Adolescents (EREMIND-A), consisting of 18 items and three factors (Attention-Concentration in the present moment; Relaxation (abilities and attitudes); and Sensory awareness/Contemplation/ Interiority). Method: The validation was done with a sample of Secondary Education and Baccalaureate students from four different centres in Spain (n = 1.120). EFA and CFA of the EREMIND-A were performed and construct and incremental validities calculated. Results: Initial results confi rm the validity and reliability of the scale. Conclusions: There is a need for a broader conceptualization of mindfulness, as well as the inclusion and analysis of other related and cross-cutting concepts. The research in this sense will propitiate the adaptation of the Mindfulness- Based Interventions to the reality of the adolescents in the educational centers, where relaxation and the interiority are aspects to be taken into consideration. © 2018 Psicothema.Antecedentes: el objetivo de esta investigación fue validar la Escala de relajación-Mindfulness para Adolescentes (EREMIND-A), que contiene 18 ítems y tres factores (Atención-Concentración en el momento presente; Relajación (habilidades y actitudes); Consciencia Sensorial/Contemplación/Interioridad. Método: la validación se realizó con una muestra de estudiantes de Educación Secundaria y Bachillerato de cuatro centros diferentes en España (n = 1.120). Se realizaron análisis factoriales exploratorios y confirmatorios de la escala y se calcularon la validez de constructo e incremental. Resultados: los resultados iniciales confirman la fiabilidad y validez de la escala. Conclusiones: es necesaria una conceptualización más amplia de la atención plena, así como la inclusión y análisis de otros conceptos relacionados y transversales. La investigación en este sentido propiciará la adaptación de las intervenciones basadas en mindfulness a la realidad de los adolescentes en los centros educativos, donde la relajación y la interioridad son aspectos a tener en consideración.http://www.psicothema.com/pdf/4475.pd

    A New Algebraization of the Lame Equation

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    We develop a new way of writing the Lame Hamiltonian in Lie-algebraic form. This yields, in a natural way, an explicit formula for both the Lame polynomials and the classical non-meromorphic Lame functions in terms of Chebyshev polynomials and of a certain family of weakly orthogonal polynomialsComment: Latex2e with AMS-LaTeX and cite packages; 32 page

    Sensores: De los biosensores a la nariz electrónica

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    The recent advances in sensor devices have allowed the developing of new applications in many technological fields. This review describes the current state-of-the-art of this sensor technology, placing special emphasis on the food applications. The design, technology and sensing mechanism of each type of sensor are analysed. A description of the main characteristics of the electronic nose and electronic tongue (taste sensors) is also given. Finally, the applications of some statistical procedures in sensor systems are described briefly.Los recientes avances en los sistemas de sensores han permitido el desarrollo de nuevas aplicaciones en muchos campos tecnológicos. Este artículo de revisión describe el estado actual de esta nueva tecnología, con especial énfasis en las aplicaciones alimentarias. El diseño, la tecnología y el mecanismo sensorial de cada tipo de sensor son analizados en el artículo. También se describen las principales características de la nariz y la lengua electrónica (sensores de sabor). Finalmente, se describe brevemente el uso de algunos procedimientos estadísticos en sistemas de sensores.Peer reviewe

    A multifrequency method based on the Matched Multifilter for the detection of point sources in CMB maps

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    In this work we deal with the problem of simultaneous multifrequency detection of extragalactic point sources in maps of the Cosmic Microwave Background. We apply a linear filtering technique that uses spatial information and the cross-power spectrum. To make this, we simulate realistic and non-realistic flat patches of the sky at two frequencies of Planck: 44 and 100 GHz. We filter to detect and estimate the point sources and compare this technique with the monofrequency matched filter in terms of completeness, reliability, flux and spectral index accuracy. The multifrequency method outperforms the matched filter at the two frequencies and in all the studied cases in the work.Comment: 14 pages, 6 figures, 1 tabl
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