283 research outputs found
Validación de la escala de ansiedad hacia las matemáticas (EAnM) y determinación de la relación entre ansiedad hacia las matemáticas, rendimiento académico y variables demográficas en escolares Españoles
75 p.La presente investigación pretende validar la Escala de Ansiedad Hacia las Matemáticas –EAnM- creada por Arias & Palacios (2015), en una muestra de 588 estudiantes de educación secundaria y bachillerato procedentes de diversas ciudades de España, cuyas edades fluctuaron entre 12 a 19 años de edad. Con el fin de determinar la validez de constructo, es que se realizó un análisis factorial exploratorio (AFE), con el método de extracción mínimos cuadrados no ponderados y una rotación promax en la muestra final de participantes (n=410). Los resultados arrojados en el AFE dieron cuenta de un solo factor preponderante, lo cual es coherente con lo expuesto por Arias & Palacios (2015) en su investigación. Sin embargo la escala EAnM, que originalmente era de 20 ítems, quedó finalmente conformada por 17 ítems debido a los criterios de eliminación. Además para determinar la fiabilidad de la se observó el índice Omega de McDonald -.95- y el índice de Alfa de Cronbach -.94-. A su vez se investigó la validez de criterio, en la que se utilizó el rendimiento académico para la relación, y cuyos resultados arrojaron que la ansiedad se relacionó de forma negativa y moderada con el rendimiento en matemáticas (r=.44). Así mismo, se analizaron diferencias por edad y género, resultando que los escolares de entre 12 a 15 años muestran niveles ligeramente más elevados de ansiedad hacia las matemáticas que los estudiantes de mayor edad, así como las mujeres muestran niveles de ansiedad matemática más altos que los hombres.Palabras Claves: Ansiedad, Ansiedad hacia las Matemáticas, Análisis Factorial Exploratorio (AFE), Rendimiento Académico, Validació
Multi feature-rich synthetic colour to improve human visual perception of point clouds
Although point features have shown their usefulness in classification with Machine Learning, point cloud visualization enhancement methods focus mainly on lighting. The visualization of point features helps to improve the perception of the 3D environment. This paper proposes Multi Feature-Rich Synthetic Colour (MFRSC) as an alternative non-photorealistic colour approach of natural-coloured point clouds. The method is based on the selection of nine features (reflectance, return number, inclination, depth, height, point density, linearity, planarity, and scattering) associated with five human perception descriptors (edges, texture, shape, size, depth, orientation). The features are reduced to fit the RGB display channels. All feature permutations are analysed according to colour distance with the natural-coloured point cloud and Image Quality Assessment. As a result, the selected feature permutations allow a clear visualization of the scene's rendering objects, highlighting edges, planes, and volumetric objects. MFRSC effectively replaces natural colour, even with less distorted visualization according to BRISQUE, NIQUE and PIQE. In addition, the assignment of features in RGB channels enables the use of MFRSC in software that does not support colorization based on point attributes (most commercially available software). MFRSC can be combined with other non-photorealistic techniques such as Eye-Dome Lighting or Ambient Occlusion.Xunta de Galicia | Ref. ED481B-2019-061Xunta de Galicia | Ref. ED431F 2022/08Agencia Estatal de Investigación | Ref. PID2019-105221RB-C43Universidade de Vigo/CISU
Hydrothermal carbonization of olive tree pruning as a sustainableway for improving biomass energy potential: effect of reaction parameters on fuel properties
Hydrothermal carbonization (HTC) allows the conversion of organic waste into a solid product called hydrochar with improved fuel properties. Olive tree pruning biomass (OTP), a very abundant residue in Mediterranean countries, was treated by HTC to obtain a solid fuel similar to coal that could be used in co-combustion processes. Three different reaction temperatures (220, 250, and 280 °C) and reaction times (3, 6, and 9 h) were selected. The hydrochars obtained were extensively analyzed to study their behavior as fuel (i.e., ultimate, proximate, fiber and thermogravimetric analysis, Fourier-transform infrared spectroscopy (FTIR), activation energy, and combustion performance). The concentrations of cellulose, hemicellulose, and lignin in the samples depict a clear and consistent trend with the chemical reactions carried out in this treatment. Regarding O/C and H/C ratios and HHV, the hydrochars generated at more severe conditions are similar to lignite coal, reaching values of HHV up to 29.6 MJ kg-1. The higher stability of the solid is reflected by the increase of the activation energy (≈60 kJ mol-1), and ignition temperatures close to 400 °C. With this, HTC is a proper thermal treatment for the management of raw OTP biomass and its further conversion into a solid biofuel.Judith González-Arias would like to thank the Junta de Castilla y León (Consejería de
Educación) fellowship, Orden EDU/1100/2017, cofinanced by the European Social Fund.info:eu-repo/semantics/publishedVersio
Current productive situation of cattle farms in Spain: The Cantabrian Cornice case
[ES] Este trabajo caracteriza desde el punto de vista productivo y socioeconómico las explotaciones con bovino en la Cornisa Cantábrica y España, además de analizar la evolución reciente de los principales indicadores de ajuste entre 2007 y el año 2016. Para lograr este objetivo se han utilizado las principales magnitudes agrarias, relativas al número de explotaciones, superficie, ganado, trabajo y valor económico de la producción. Los resultados obtenidos muestran una concentración territorial, especialización y concentración productiva del bovino, junto a un avance del proceso de ajuste estructural.[EN] This study characterizes, from a productive and socioeconomic point of view, the cattle farms in Cantabrian Cornice and Spain, besides analyzing recent evolution of the main adjustment indicators between 2007 and 2016. In doing so, we have analyzed the main agricultural magnitudes, relative to the number of farms, land, livestock, labor and economic value of production. The results obtained show a territorial concentration, specialization and productive concentration of the cattle, together with an advance of the structural adjustment process.Este trabajo ha sido financiado por el INIA, mediante el contrato predoctoral FPI-INIA, convocatoria 2015 (Sostenibilidad económica de las explotaciones de bovino en Cantabria).García-Suárez, E.; García-Arias, AI.; Vázquez-González, I. (2020). Situación productiva reciente de las explotaciones con bovino en España: el caso de la Cornisa Cantábrica. Economía Agraria y Recursos Naturales - Agricultural and Resource Economics. 19(2):93-111. https://doi.org/10.7201/earn.2019.02.05OJS9311119
SCRATCH EN LA FORMACIÓN DE JÓVENES Y ADULTOS COMO PRODUCTORES CREATIVOS
El trabajo responde a la necesidad del perfeccionamiento del currículo de Computación de la Misión “José Félix Ribas” de la República Bolivariana de Venezuela. En el diagnóstico inicial se constató que la asignatura se caracterizaba por contenidos desactualizados y una metodología de enseñanza limitada fundamentalmente a las videoclases. El proceso para perfeccionar el currículo incluyó, entre otros elementos, un diagnóstico, el estudio de concepciones actuales sobre la enseñanza de la informática y el intercambio en las Mesas de Trabajo. Una de las propuestas innovadoras lo constituye el diseño del tema Computación Creativa, que además de proponer objetivos y contenidos novedosos, combina las videoclases con el aprendizaje por proyectos. Para contribuir a la preparación de estudiantes y docentes se elaboraron dos materiales didácticos digitales, que incluyen ejemplos de proyectos relacionados con la historia de Venezuela y la Revolución Bolivariana. Esta propuesta responde de una manera más adecuada al contexto actual venezolano, donde se exige la formación de ciudadanos con una cultura de productores, con solidez ideológica y que participen de forma protagónica en la defensa de la Revolución Bolivariana. La propuesta fue valorada positivamente por los docentes que participaron en las Mesas de Trabajo, y por directivos de la Misión Ribas. 
Immigrant IBD Patients in Spain Are Younger, Have More Extraintestinal Manifestations and Use More Biologics Than Native Patients
Background: Previous studies comparing immigrant ethnic groups and native patients with IBD have yielded clinical and phenotypic differences. To date, no study has focused on the immigrant IBD population in Spain.
Methods: Prospective, observational, multicenter study comparing cohorts of IBD patients from ENEIDA-registry who were born outside Spain with a cohort of native patients.
Results: We included 13,524 patients (1,864 immigrant and 11,660 native). The immigrants were younger (45 ± 12 vs. 54 ± 16 years, p < 0.001), had been diagnosed younger (31 ± 12 vs. 36 ± 15 years, p < 0.001), and had a shorter disease duration (14 ± 7 vs. 18 ± 8 years, p < 0.001) than native patients. Family history of IBD (9 vs. 14%, p < 0.001) and smoking (30 vs. 40%, p < 0.001) were more frequent among native patients. The most prevalent ethnic groups among immigrants were Caucasian (41.5%), followed by Latin American (30.8%), Arab (18.3%), and Asian (6.7%). Extraintestinal manifestations, mainly musculoskeletal affections, were more frequent in immigrants (19 vs. 11%, p < 0.001). Use of biologics, mainly anti-TNF, was greater in immigrants (36 vs. 29%, p < 0.001). The risk of having extraintestinal manifestations [OR: 2.23 (1.92–2.58, p < 0.001)] and using biologics [OR: 1.13 (1.0–1.26, p = 0.042)] was independently associated with immigrant status in the multivariate analyses.
Conclusions: Compared with native-born patients, first-generation-immigrant IBD patients in Spain were younger at disease onset and showed an increased risk of having extraintestinal manifestations and using biologics. Our study suggests a featured phenotype of immigrant IBD patients in Spain, and constitutes a new landmark in the epidemiological characterization of immigrant IBD populations in Southern Europe
Clarithromycin Effect in Microbial Communities
Financiaciado para publicación en acceso aberto: Universidade de Vigo/CISUGA laboratory experiment was carried out to investigate the response of the microbial communities in acid agricultural soils located in the NW Iberian Peninsula to the presence of clarithromycin. Four soils, with different organic C content and similar pH, and seven different concentrations of clarithromycin (0.49, 1.95, 7.81, 31.25, 125, 500 and 2,000 mg kg−1 of soil) were used, and microbial estimates were made after 8 and 42 incubation days. The phospholipid fatty acids (PLFA) technique was used to estimate the total microbial biomass and biomass of specific microbial groups as well as the microbial community structure (PLFA pattern). The microbial biomass (total and specific groups) was different in the four studied soils, the lowest values being exhibited by soils with the lowest organic C. The antibiotic addition showed a positive effect on microbial biomass (total and specific groups), especially at the highest dose; the effect being similar or even more accentuated with time passed after the addition (42 days ≥8 days). Principal component analysis (PCA) of the PLFA data carried out with the whole data set showed that the main determining factors of the microbial structure followed the order: soil > time incubation ≥ antibiotic dose. When the PCA was performed individually for each incubation time, the results indicated that microbial communities of the four soils were different. Likewise, for each soil, different microbial communities were observed depending on antibiotic concentration. The microbial biomass and PLFA pattern data were coincidentally showing that the clarithromycin addition favored fungi and G− bacteria more that bacteria and G+ bacteria; the effect being dose-dependent. Our data (microbial biomass, PLFA pattern) also demonstrated that the effect of clarithromycin addition on microbial communities in these four acid agricultural soils persisted even after 42 incubation days.Xunta de Galicia | Ref. ED481B-2022-081Ministerio de Ciencia, Innovación y Universidades | Ref. RTI2018-099574-B-C21Ministerio de Ciencia, Innovación y Universidades | Ref. RTI2018-099574-B-C22Ministerio de Ciencia, Innovación y Universidades | Ref. FPU21/0420
Ectopic overexpression of the cell wall invertase gene CIN1 leads to dehydration avoidance in tomato
Drought stress conditions modify source–sink relations, thereby influencing plant growth, adaptive responses, and
consequently crop yield. Invertases are key metabolic enzymes regulating sink activity through the hydrolytic cleavage
of sucrose into hexose monomers, thus playing a crucial role in plant growth and development. However, the physiological
role of invertases during adaptation to abiotic stress conditions is not yet fully understood. Here it is shown
that plant adaptation to drought stress can be markedly improved in tomato (Solanum lycopersicum L.) by overexpression
of the cell wall invertase (cwInv) gene CIN1 from Chenopodium rubrum. CIN1 overexpression limited stomatal
conductance under normal watering regimes, leading to reduced water consumption during the drought period, while
photosynthetic activity was maintained. This caused a strong increase in water use efficiency (up to 50%), markedly
improving water stress adaptation through an efficient physiological strategy of dehydration avoidance. Drought stress
strongly reduced cwInv activity and induced its proteinaceous inhibitor in the leaves of the wild-type plants. However,
the CIN1-overexpressing plants registered 3- to 6-fold higher cwInv activity in all analysed conditions. Surprisingly,
the enhanced invertase activity did not result in increased hexose concentrations due to the activation of the metabolic
carbohydrate fluxes, as reflected by the maintenance of the activity of key enzymes of primary metabolism and
increased levels of sugar-phosphate intermediates under water deprivation. The induced sink metabolism in the leaves
explained the maintenance of photosynthetic activity, delayed senescence, and increased source activity under drought
stress. Moreover, CIN1 plants also presented a better control of production of reactive oxygen species and sustained
membrane protection. Those metabolic changes conferred by CIN1 overexpression were accompanied by increases
in the concentrations of the senescence-delaying hormone trans-zeatin and decreases in the senescence-inducing
ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) in the leaves. Thus, cwInv critically functions at the integration point of metabolic, hormonal, and stress signals, providing a novel strategy to overcome drought-induced
limitations to crop yield, without negatively affecting plant fitness under optimal growth conditions.España Ministerio de Ciencia e Innovación AT2009-0038 and AGL2011-2799
Evaluation of Joint Management of Pine Wood Waste and Residual Microalgae for Agricultural Application
[EN] This work addresses the joint management of residual microalgae and pine wood waste through pyrolysis to obtain a solid product for its use as soil amendment and two other by-products (liquid and gaseous) that can be used for energy purposes. Two management routes have been followed. The first route is through the co-pyrolysis of mixtures of both residual materials in several proportions and the later use of their solid fraction for soil amendment. The second route is the pyrolysis of pine wood waste and its direct combination with dried residual microalgae, also using it as soil amendment. The solid fraction assessment shows that from seven solid products (biochar) three stand out for their positive applicability in agriculture as soil amendment. In addition, they also present the benefit of serving as carbon sink, giving a negative balance of CO2 emissions. However, caution is suggested due to biochar applicability being subject to soil characteristics. To ensure the sustainability of the overall process, the energy available in liquid and gaseous fractions has been assessed for covering the drying needs of the residual microalgae in both cases. These results suggest that the pyrolysis process is a sustainable way to manage specific evaluated residues and their products.S
Role of transcription factor Sp1 and CpG methylation on the regulation of the human podocalyxin gene promoter
BACKGROUND: Podocalyxin (podxl) is a heavily glycosylated transmembrane protein mainly found on the apical membrane of rat podocytes and also in endothelial, hematopoietic, and tumor cells. Despite of its interest no much is known about the transcriptional regulation of podxl in different cells. Thus, we aimed at studying the functional features of the 5'-regulatory region of the human Podxl gene. RESULTS: The promoter region of the human Podxl gene has been cloned and its structure and function were analyzed. The primary DNA sequence is rich in G+C and is devoid of TATA or CAAT boxes. The sequence contains recognition sites for several putative transcription factors; however, the basic promoter activity seems to rely entirely on Sp1 transcription factor since supershift analysis was positive only for this factor. The region encompassed by 66 to -111 nts conferred the minimal transcriptional activity that increases as the number of Sp1 sites augmented with the length of the promoter fragment. In Sp1-lacking insect cells the Podxl promoter constructs showed activity only if cotransfected with an Sp1 expression plasmid. Finally, mutation of the Sp1 sites reduced the promoter activity. We analyzed whether methylation of the CpG dinucleotides present in the first ~600 nts of the promoter region of Podxl could explain the variable rates of expression in different types of cells. Inactivation of methyltransferases by 5'-aza-2'deoxicitidine showed a dose-dependent increase in the podxl content. Moreover, in vitro methylation of the promoter constructs -111,-181 and -210 led to an almost complete reduction of the promoter activity. A correlation was found between the degree of methylation of the CpG promoter dinucleotides and the rate of podxl expression in different cell lines. CONCLUSION: Our results indicate that transcriptional regulation of Podxl is supported primarily by Sp1 site(s) and that DNA-methylation of the CpG promoter islands contributes to control the tissue specific expression of podxl
- …