Ansiedad matemática en estudiantes universitarios de Costa Rica y su relación con el rendimientos académico y variables sociodemográficas

The study tried to determine the relationship between mathematics anxiety and the variables of gender, academic achievement, number of times students have taken the course and type of school in students taking the course MAT-001 General Mathematics of the National University of Costa Rica. To that end, a purposive sample of 472 students of such course was collected and the instrument of Hopko, Mahadevan, Bare and Hunt was adjusted to it (2003). Data collected were analyzed with the statistical program SPSS applying the corresponding hypothesis tests. According with the results, students showed a medium level of math anxiety and women showed a math anxiety significantly higher than men, while student graduated from private schools showed a significantly lower level of math anxiety than those from public schools or from the modality “General Equivalency Diploma”. Besides, the higher the math anxiety of the student is, the lower their academic achievement will be. Finally, there were no statistically significant differences between math anxiety and the number of times students have taken the course.El estudio buscó determinar la relación entre ansiedad matemática y las variables género, rendimiento académico, cantidad de veces que ha llevado el curso y tipo de colegio, en estudiantes del curso MAT-001 Matemática General de la Universidad Nacional de Costa Rica. Para ello se escogió una muestra intencional de 472 alumnos de dicho curso y se les aplicó una adecuación del instrumento de Hopko, Mahadevan, Bare y Hunt (2003). Los datos recolectados fueron analizados con el programa estadístico SPSS aplicando las pruebas de hipótesis correspondientes. De acuerdo con los resultados,  se encontró que los estudiantes presentaron un nivel medio de ansiedad Matemática y que las mujeres mostraron una ansiedad matemática significativamente mayor que los hombres; mientras que los estudiantes egresados de colegios privados obtuvieron una ansiedad matemática significativamente menor que los provenientes de colegios públicos o de la modalidad de “bachillerato por madurez”. De igual forma resultó que entre mayor es la ansiedad matemática del estudiante su rendimiento académico será significativamente menor. Por último, no se encontraron diferencias estadísticamente significativas entre  la ansiedad matemática y la cantidad de veces que el estudiante ha llevado el curso

Ansiedad matemática en estudiantes universitarios de Costa Rica y su relación con el rendimientos académico y variables sociodemográficas

The study tried to determine the relationship between mathematics anxiety and the variables of gender, academic achievement, number of times students have taken the course and type of school in students taking the course MAT-001 General Mathematics of the National University of Costa Rica. To that end, a purposive sample of 472 students of such course was collected and the instrument of Hopko, Mahadevan, Bare and Hunt was adjusted to it (2003). Data collected were analyzed with the statistical program SPSS applying the corresponding hypothesis tests. According with the results, students showed a medium level of math anxiety and women showed a math anxiety significantly higher than men, while student graduated from private schools showed a significantly lower level of math anxiety than those from public schools or from the modality “General Equivalency Diploma”. Besides, the higher the math anxiety of the student is, the lower their academic achievement will be. Finally, there were no statistically significant differences between math anxiety and the number of times students have taken the course.El estudio buscó determinar la relación entre ansiedad matemática y las variables género, rendimiento académico, cantidad de veces que ha llevado el curso y tipo de colegio, en estudiantes del curso MAT-001 Matemática General de la Universidad Nacional de Costa Rica. Para ello se escogió una muestra intencional de 472 alumnos de dicho curso y se les aplicó una adecuación del instrumento de Hopko, Mahadevan, Bare y Hunt (2003). Los datos recolectados fueron analizados con el programa estadístico SPSS aplicando las pruebas de hipótesis correspondientes. De acuerdo con los resultados,  se encontró que los estudiantes presentaron un nivel medio de ansiedad Matemática y que las mujeres mostraron una ansiedad matemática significativamente mayor que los hombres; mientras que los estudiantes egresados de colegios privados obtuvieron una ansiedad matemática significativamente menor que los provenientes de colegios públicos o de la modalidad de “bachillerato por madurez”. De igual forma resultó que entre mayor es la ansiedad matemática del estudiante su rendimiento académico será significativamente menor. Por último, no se encontraron diferencias estadísticamente significativas entre  la ansiedad matemática y la cantidad de veces que el estudiante ha llevado el curso

Determinación de órganos diana para la multiplicación y persistencia del virus de la enfermedad de linfocistis (LCDV) en dorada (Sparus aurata, L.)

La enfermedad de linfocistis es la única patología de etiología viral descrita en dorada cultivada En la cuenca mediterr nea, la prevalencia es cercana al 100 , ocasionando graves p rdidas económicas debido a la imposibilidad de comercializar los peces afectados En el presente trabajo se ha abordado el estudio de la patog nesis del virus de la enfermedad de linfocistis (LCDV) en dorada, además se han establecido los órganos implicados en la multiplicación vírica Para ello, se ha diseñado un protocolo de hibridación in situ empleando sondas RNA marcadas con digoxigenina dirigidas contra el gen que codifica la proteína principal de la cápside (MCP) viral, y se ha evaluado en poblaciones de dorada. En paralelo, se ha procedido a la cuantificación del número de copias de genoma viral por PCR a tiempo real y cuantificación relativa de la transcripción del gen que codifica la MCP viral mediante qRT-PCR. Los resultados obtenidos indican que el LCDV establece una infección sistémica en alevines de dorada, pudiendo detectarse señal de hibridación tanto en órganos internos (hígado, bazo, riñón) como en músculo y aleta. También se han observado diversos daños histopatológicos en animales enfermos, mientras que en animales recuperados de la enfermedad estos daños parecen revertir, aunque en estos animales la infección persiste, si bien sólo a niveles detectables mediante PCR a tiempo real.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Basal gnathostomes provide unique insights into the evolution of vitamin B12 binders

© The Author(s), 2014. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Genome Biology and Evolution 7 (2015): 457-464, doi:10.1093/gbe/evu289.The uptake and transport of vitamin B12 (cobalamin; Cbl) in mammals involves a refined system with three evolutionarily related transporters: transcobalamin 1 (Tcn1), transcobalamin 2 (Tcn2), and the gastric intrinsic factor (Gif). Teleosts have a single documented binder with intermediate features to the human counterparts. Consequently, it has been proposed that the expansion of Cbl binders occurred after the separation of Actinopterygians. Here, we demonstrate that the diversification of this gene family took place earlier in gnathostome ancestry. Our data indicates the presence of single copy orthologs of the Sarcopterygii/Tetrapoda duplicates Tcn1 and Gif, and Tcn2, in Chondrichthyes. In addition, a highly divergent Cbl binder was found in the Elasmobranchii. We unveil a complex scenario forged by genome, tandem duplications and lineage-specific gene loss. Our findings suggest that from an ancestral transporter, exhibiting large spectrum and high affinity binding, highly specific Cbl transporters emerged through gene duplication and mutations at the binding pocket.This work was funded by the Fundação para a Ciência e a Tecnologia (FCT) project PEst-C/MAR/LA0015/2013. PhD grant SFRH/BD/84238/2012 awarded to M.L-.M. Postdoctoral grant SFRH/BPD/72519/2010 awarded to R.R

Sources of hepatic triglyceride accumulation during high-fat feeding in the healthy rat

Hepatic triglyceride (HTG) accumulation from peripheral dietary sources and from endogenous de novo lipogenesis (DNL) was quantified in adult Sprague-Dawley rats by combining in vivo localized 1H MRS measurement of total hepatic lipid with a novel ex vivo 2H NMR analysis of HTG 2H enrichment from 2H-enriched body water. The methodology for DNL determination needs further validation against standard methodologies. To examine the effect of a high-fat diet on HTG concentrations and sources, animals (n = 5) were given high-fat chow for 35 days. HTG accumulation, measured by in vivo 1H MRS, increased significantly after 1 week (3.85 ± 0.60% vs 2.13 ± 0.34% for animals fed on a standard chow diet, P < 0.05) and was maintained until week 5 (3.30 ± 0.60% vs 1.12 ± 0.30%, P < 0.05). Animals fed on a high-fat diet were glucose intolerant (13.3 ± 1.3 vs 9.4 ± 0.8 mM in animals fed on a standard chow diet, for 60 min glycemia after glucose challenge, P < 0.05). In control animals, DNL accounted for 10.9 ± 1.0% of HTG, whereas in animals given the high-fat diet, the DNL contribution was significantly reduced to 1.0 ± 0.2% (P < 0.01 relative to controls). In a separate study to determine the response of HTG to weaning from a high-fat diet, animals with raised HTG (3.33 ± 0.51%) after 7days of a high-fat diet reverted to basal HTG concentrations (0.76 ± 0.06%) after an additional 7 days of weaning on a standard chow diet. These studies show that, in healthy rats, HTG concentrations are acutely influenced by dietary lipid concentrations. Although the DNL contribution to HTG content is suppressed by a high-fat diet in adult Sprague-Dawley rats, this effect is insufficient to prevent overall increases in HTG concentrations. Copyright © 2008 John Wiley & Sons, Ltd

Radial and tangential migration of telencephalic somatostatin neurons originated from the mouse diagonal area

The telencephalic subpallium is the source of various GABAergic interneuron cohorts that invade the pallium via tangential migration. Based on genoarchitectonic studies, the subpallium has been subdivided into four major domains: striatum, pallidum, diagonal area and preoptic area (Puelles et al. 2013; Allen Developing Mouse Brain Atlas), and a larger set of molecularly distinct progenitor areas (Flames et al. 2007). Fate mapping, genetic lineage-tracing studies, and other approaches have suggested that each subpallial subdivision produces specific sorts of inhibitory interneurons, distinguished by differential peptidic content, which are distributed tangentially to pallial and subpallial target territories (e.g., olfactory bulb, isocortex, hippocampus, pallial and subpallial amygdala, striatum, pallidum, septum). In this report, we map descriptively the early differentiation and apparent migratory dispersion of mouse subpallial somatostatin-expressing (Sst) cells from E10.5 onward, comparing their topography with the expression patterns of the genes Dlx5, Gbx2, Lhx7-8, Nkx2.1, Nkx5.1 (Hmx3), and Shh, which variously label parts of the subpallium. Whereas some experimental results suggest that Sst cells are pallidal, our data reveal that many, if not most, telencephalic Sst cells derive from de diagonal area (Dg). Sst-positive cells initially only present at the embryonic Dg selectively populate radially the medial part of the bed nucleus striae terminalis (from paraseptal to amygdaloid regions) and part of the central amygdala; they also invade tangentially the striatum, while eschewing the globus pallidum and the preoptic area, and integrate within most cortical and nuclear pallial areas between E10.5 and E16.5.This work was funded by the Spanish Ministry of Science and Innovation grant BFU2008-04156, and SENECA Foundation contract 0458/GERM/06-10891 to L.P.; and the Local Government of Castilla-La Mancha grant PII1I09-0065-8194 to C.D. Infrastructure support provided by the University of Murcia and Castilla-La Mancha is also acknowledged

Ansiedad matemática en estudiantes universitarios de Costa Rica y su relación con el rendimientos académico y variables sociodemográficas

The study tried to determine the relationship between mathematics anxiety and the variables of gender, academic achievement, number of times students have taken the course and type of school in students taking the course MAT-001 General Mathematics of the National University of Costa Rica. To that end, a purposive sample of 472 students of such course was collected and the instrument of Hopko, Mahadevan, Bare and Hunt was adjusted to it (2003). Data collected were analyzed with the statistical program SPSS applying the corresponding hypothesis tests. According with the results, students showed a medium level of math anxiety and women showed a math anxiety significantly higher than men, while student graduated from private schools showed a significantly lower level of math anxiety than those from public schools or from the modality “General Equivalency Diploma”. Besides, the higher the math anxiety of the student is, the lower their academic achievement will be. Finally, there were no statistically significant differences between math anxiety and the number of times students have taken the course.El estudio buscó determinar la relación entre ansiedad matemática y las variables género, rendimiento académico, cantidad de veces que ha llevado el curso y tipo de colegio, en estudiantes del curso MAT-001 Matemática General de la Universidad Nacional de Costa Rica. Para ello se escogió una muestra intencional de 472 alumnos de dicho curso y se les aplicó una adecuación del instrumento de Hopko, Mahadevan, Bare y Hunt (2003). Los datos recolectados fueron analizados con el programa estadístico SPSS aplicando las pruebas de hipótesis correspondientes. De acuerdo con los resultados,  se encontró que los estudiantes presentaron un nivel medio de ansiedad Matemática y que las mujeres mostraron una ansiedad matemática significativamente mayor que los hombres; mientras que los estudiantes egresados de colegios privados obtuvieron una ansiedad matemática significativamente menor que los provenientes de colegios públicos o de la modalidad de “bachillerato por madurez”. De igual forma resultó que entre mayor es la ansiedad matemática del estudiante su rendimiento académico será significativamente menor. Por último, no se encontraron diferencias estadísticamente significativas entre  la ansiedad matemática y la cantidad de veces que el estudiante ha llevado el curso

Light elements in stars with exoplanets

It is well known that stars orbited by giant planets have higher abundances of heavy elements when compared with average field dwarfs. A number of studies have also addressed the possibility that light element abundances are different in these stars. In this paper we will review the present status of these studies. The most significant trends will be discussed.Comment: 10 pages, 6 figures. Submitted to the proceedings of IAU symposium 268: Light elements in the universe

Genotype by environment interaction and adaptability of photoperiod-sensitive biomass sorghum hybrids.

Biomass sorghum is an alternative feedstock to cogenerate energy and produce second-generation ethanol. The aim of this study was to evaluate the Genotype by Environment Interaction (GEI) in biomass sorghum and to identify the hybrids that associate high adaptability and stability using the Toler nonlinear regression, the Genotypes plus Genotype by Environment (GGE) biplot, and the Annicchiarico recommendation index. Thirty-three experimental photoperiod-sensitive single-cross hybrids and three checks were evaluated in relation to the traits: flowering time, plant height, moisture content, green mass yield, and dry mass yield. It was observed that the effects of hybrids, environment, and GEI were expressive. The GEI was predominantly complex for the traits related to the biomass yield. The Toler, GGE biplot and Annicchiarico methods show complementarity. The experimental hybrids 1, 8, 22, 31 and 33 are promising because of associating stability and lower recommendation risk. The hybrids 1 and 8 present broad adaptability, while the hybrids 22, 31 and 33 exhibit specific adaptability to high quality environments

Potential risk of Artemia sp as a transmission vector of lymphocystis disease virus (LCDV)

4 páginas, 1 figura. XI Congreso Nacional de Acuicultura (Vigo, 24-28 septiembre 2007). Ed. Antonio Cerviño Eiroa, Alejandro Guerra Díaz y Carmen Pérez Acosta.[EN] Cysts and naupliis of Artemia sp. were analysed. Specific nested-PCR revealed lymphocystis disease virus (LCDV) genome. Infective viral particle has been observed by CPE development in inoculated cell cultures. Viral genome was found by in situ hybridization in nauplii and adults of natural infected artemia, as in nauplii of bath challenged artemia. No morphological damages have been observed. Artemia is a bio-accumulator of fish pathogens, with a possible role as environmental reservoir of fish pathogens. These results have shown the risk of artemia as a source of viral pathogens to fish larvae.[ES] En el presente trabajo se han realizado estudios virológicos en distintos lotes de quistes comerciales de artemias utilizados como alimento de larvas de peces marinos en piscifactorías. Mediante nested-PCR se ha detectado genoma del virus de linfocistis (LCDV) en homogeneizados de quistes y nauplios de artemia. La existencia de partículas víricas infectivas en estos homogeneizados se ha demostrado mediante la aparición de efectos citopáticos en cultivos celulares. Los ensayos de hibridación in situ han demostrado la existencia del LCDV en artemias infectadas naturalmente, así como en artemias inoculadas mediante baño, sin observarse alteraciones morfológicas. Las artemias actúan por tanto como bioacumuladores, pudiendo desempeñar un papel importante como reservorios ambientales de patógenos de peces. Estos resultados ponen de manifiesto el riesgo potencial de las artemias como fuente de patógenos víricos en estadios larvarios.Irene Cano es contratada postdoctoral en el ICMAN.CSIC dentro del Fondo social europeo- I3P-CSIC, en el marco del proyecto AGL2006-17777-C03-02/ACU (IP: Carmen Sarasquete).Peer reviewe