447 research outputs found
¿La igualdad es real en el deporte?: análisis de la práctica físico-deportiva desde una perspectiva de género
El presente estudio tiene como objetivo realizar un análisis que establezca las diferencias que existen en el ámbito deportivo desde una perspectiva de género. Para ello, el lector/a será informado de la evolución de la mujer en el deporte, del intento de la ley por fomentar la igualdad de género y del concepto “coeducación”. Asimismo, se realiza un cuestionario a alumnos y alumnas de Educación Primaria, Educación Secundaria y Bachillerato; y a personas que comprendan las edades de 18 y 35 años. De esta forma, se comparan los resultados obtenidos con los de otras fuentes consultadas y correspondientes a años anteriores para entender que hay un progreso evidente. No obstante, aún se siguen percibiendo actitudes muy discriminatorias y diferencias muy significativas si se atiende a la variable del sexo del encuestado/a.
Por último, se desea sensibilizar a la sociedad acerca de la desigualdad existente entre hombres y mujeres dentro de un marco deportivo y, como consecuencia, de las diferentes causas que la ocasionan.The present study aims to perform an analysis that establishes the differences that exist in the sports field from a gender perspective. For this, the reader will be informed of the evolution of women in sports, of the attempt of the law to promote gender equality and the concept of "coeducation". Likewise, a questionnaire is made to students of Primary Education, Secondary Education and Bachillerato; and to people who understand the ages of 18 and 35 years. In this way, the results obtained are compared with those of other sources consulted and corresponding to previous years to understand that there is evident progress. Nonetheless, very discriminatory attitudes and very significant differences are still perceived if the respondent's sex variable is considered. Finally, we want to sensitize society about the inequality between men and women within a sporting framework and, as a consequence, the different causes that cause it.Universidad de Sevilla. Grado en Educación Primari
DIPLOMACIA CULTURAL EN COLOMBIA Y SU INCLUSIÓN EN GESTIÓN PÚBLICA
En el presente artículo se demuestra como la gestión en políticas públicasa partir de la diplomacia cultural aporta al desarrollo económico y social enAmérica Latina. En este sentido, se realizó una revisión y análisis documental.En estudio se resaltó la diplomacia cultural como instrumento de desarrollosostenible influye en la calidad de vida de una sociedad, permitiendoafrontar los retos globales de competitividad
Propuestas para la mejora de la interpretación del intervalo de confianza en estudiantes preuniversitarios y universitarios
La planificación y diseño de tareas es una pieza clave que todo docente debe tomar en cuenta con objeto de garantizar un proceso de enseñanza y aprendizaje significativo. El conocimiento de los errores y dificultades existentes en torno a un objeto matemático facilita esta labor al profesorado, cuyo análisis contribuirá a realizar propuestas de enseñanza que mejoren dicho proceso. En base a ello, el presente trabajo tiene como objetivo el planteamiento de propuestas de enseñanza enfocadas a solventar los errores y dificultades relacionados con los intervalos de confianza (IC) que tienen los estudiantes de bachillerato y universitarios, apoyándose en el uso de las TICs y las representaciones gráficas. Pensamos que esta forma de abordar el tema propicia una mejor comprensión de la finalidad que realmente tiene el uso de los IC
Algunos conflictos semióticos de futuros profesores al plantear las hipótesis de un contraste
La presente investigación tiene como objeto detectar y categorizar los posibles conflictos semióticos presentes en futuros profesores de Educación Secundaria y Bachillerato sobre el planteamiento de la hipótesis nula y alternativa de un contraste de hipótesis. Se ha contado con la colaboración de 73 futuros profesores del Máster de Educación Secundaria de la Universidad de Granada, a los que se le ha propuesto un problema de contraste de hipótesis similar a los recogidos en las pruebas de acceso a la universidad en cursos anteriores. Mediante un análisis de contenido de las respuestas dadas por los participantes, los resultados revelan conflictos de representación, procedimentales y, en su mayoría, de tipo conceptual, revelando en algunos casos una escasa comprensión de la lógica del contraste de hipótesis. Además, se han identificado dos nuevos conflictos no recogidos en la literatura previa. La información obtenida en el presente trabajo va en consonancia con los resultados señalados en investigaciones previas con estudiantes, lo que plantea una posible relación con el conocimiento de los futuros profesores y, por ende, la necesidad de mejorar su formación sobre este contenido
Quality, oxidative markers and DNA damage (DNA) fragmentation of red deer thawed spermatozoa after incubation at 37 °C in presence of several antioxidants
P. 1005-1019Antioxidants may be useful for supplementing sperm extenders. We have tested dehydroascorbic acid (DHA), TEMPOL, N-acetyl-cysteine (NAC) and rutin on epididymal spermatozoa from red deer, during incubation at 37 °C. Cryopreserved spermatozoa were thawed, washed and incubated with 1 mm or 0.1 mm of each antioxidant, including oxidative stress (Fe2+/ascorbate). Motility (CASA and clustering of subpopulations), viability, mitochondrial membrane potential, and acrosomal status were assessed at 2 and 4 h. Lipoperoxidation, intracellular reactive oxygen species (ROS) and DNA damage (DNA) status (TUNEL) were checked at 4 h. Oxidative stress increased ROS, lipoperoxidation and DNA damage. Overall, antioxidants negatively affected motility and physiological parameters. Only DHA 1 mm protected motility, increasing the fast and progressive subpopulation. However, it had a detrimental effect on acrosomal and DNA status, in absence of oxidative stress. Tempol and rutin efficiently reduced lipoperoxidation, ROS, and DNA damage in presence of oxidative stress. NAC was not as efficient as TEMPOL or rutin reducing lipoperoxidation or protecting DNA, and did not reduce ROS, but its negative effects were lower than the other antioxidants when used at 1 mm, increasing the subpopulation of hyperactivated-like spermatozoa at 2 h. Our results show that these antioxidants have mixed effects when spermatozoa are incubated at physiological temperatures. DHA may not be suitable because of prooxidant effects, but TEMPOL, NAC and rutin may be considered for cryopreservation trials. In general, exposure of red deer spermatozoa to these antioxidants should be limited to low temperatures, when only protective effects may develop.S
Participatory visioning for building disruptive future scenarios for transport and land use planning
Participatory visioning in transport scenario building can be particularly useful to anticipate and examine unexpected outcomes over long-term future timelines, providing broad legitimacy to today's decision-making processes. However, the strategic value of participatory approaches is increasingly being contested due to the difficulty to operationalize non-linear thinking, resulting in long-term visions similar to business-as-usual projections. To address this challenge, we developed and implemented a novel participatory visioning approach based on using semi-structured interviews that incorporate two types of wild cards &- low probability and high impact processes &- as disruptive visioning triggers: imaginable and unimaginable processes. A group of experts evaluated the level of disruptive thinking in the generated future visions. The Henares Corridor in the Metropolitan Area of Madrid, Spain provided the empirical focus. The results present a total of seven 2050 visions: one desired common vision plus six wild card visions. Higher levels of disruptive thinking were mainly present in those future visions generated by unimaginable processes, as such processes initiate highly diverging participant future views. It was also noted that smaller and specific groups of participants can visualize 2050 futures more disruptively. Conclusions and reflections on the strengths and weakness of the presented approach are drawn
Reactive oxygen species generators affect quality parameters and apoptosis markers differently in red deer spermatozoa
P. 225–235Fe2+/ascorbate, hydrogen peroxide (H2O2), and hypoxanthine/xanthine oxidase (XOD) are commonly used for inducing oxidative stress on spermatozoa. A comparative study of these agents was carried out on thawed spermatozoa from red deer. First, we tested a high, medium, and low concentration of each agent: 100, 10, and 1 μM Fe2+ (hydroxyl radical generator); 1 mM, 100, and 10 μM H2O2; and 100, 10, and 1 mU/ml XOD (superoxide and H2O2 generator), incubated at 37 °C for 180 min. Intracellular reactive oxygen species (ROS; H2DCFDA) increased with dose and time similarly for the three systems at each concentration level. Motility and mitochondrial membrane potential (Δψm) were considerably decreased by H2O2 (1 mM and 100 μM) and XOD (100 and 10 mU/ml). Only 1 mM H2O2 reduced viability. The antioxidant Trolox (10 μM) reduced intracellular ROS, but could not prevent the H2O2 or XOD effects. In a second experiment, YO-PRO-1 and M540 were used as apoptotic and membrane stability markers respectively. Only H2O2 increased the proportion of apoptotic and membrane-destabilized spermatozoa. Catalase added to XOD prevented Δψm loss, confirming that H2O2 was the causative agent, not superoxide. In a third experiment, caspase activation was tested using the (FAM-VAD-FMK) probe. Viable spermatozoa with activated caspases could be detected in untreated samples, and only H2O2 increased their proportion after 60 min. There were important differences between ROS generators, H2O2 being the most cytotoxic. Although H2O2 and XOD caused Δψm dissipation, this was not reflected in increasing apoptotic markers.S
Washing increases the susceptibility to exogenous oxidative stress in red deer spermatozoa
P. 1073-1084The effects of routine sperm work are often overlooked. We assessed the effect of washing cryopreserved epididymal spermatozoa from red deer (Cervus elaphus hispanicus, Helzheimer 1909). After thawing, epididymal samples (four stags) were diluted in TALP-HEPES. A split was left untouched, another was centrifuged (300 × g, 5 min) and resuspended, and a third was centrifuged and the supernatant substituted by fresh TALP-HEPES (washing). Each split was supplemented either with nothing, 1 mM of the antioxidant Trolox, 100 μM of the oxidant Fe (with ascorbate), or both. The 3 × 4 treatments were incubated at 37°C and assessed each hour up to 3 h for motility (computer-aided sperm assessment) and viability/apoptosis plus mitochondrial status (YO-PRO-1, propidium iodide, Mitotracker Deep Red; flow cytometry). DNA damage at 4 h was assessed using the terminal deoxynucleotidyl transferase–mediated dUTP nick end-labeling assay. Centrifugation alone affected neither sperm quality nor DNA, and the oxidant had no effect in control or centrifuged samples. Washed samples were not different than control, but oxidant decreased motility, mitochondrial status and viability, and altered the motility subpopulation pattern, being partially suppressed by Trolox. Spermatozoa with damaged DNA dramatically increased in the washed-oxidized sample (from 22.30 ± 3.52% to 67.94 ± 5.07%), but not when antioxidant was present. Although samples from different males behaved similarly, male-to-male variability was detected regarding susceptibility to oxidative damage after washing. We concluded that, although red deer thawed spermatozoa seemed resilient to centrifugation, the vulnerability to oxidative stress after washing makes it advisable to supplement manipulation media with antioxidants, especially taking into account male-to-male variability.S
Precision measurement of Compton scattering in silicon with a skipper CCD for dark matter detection
Experiments aiming to directly detect dark matter through particle recoils can achieve energy thresholds of
O
(
10
eV
)
. In this regime, ionization signals from small-angle Compton scatters of environmental
γ
rays constitute a significant background. Monte Carlo simulations used to build background models have not been experimentally validated at these low energies. We report a precision measurement of Compton scattering on silicon atomic shell electrons down to 23 eV. A skipper charge-coupled device with single-electron resolution, developed for the DAMIC-M experiment, was exposed to a
241
Am
γ
-ray source over several months. Features associated with the silicon K-,
L
1
-, and
L
2
,
3
-shells are clearly identified, and scattering on valence electrons is detected for the first time below 100 eV. We find that the relativistic impulse approximation for Compton scattering, which is implemented in Monte Carlo simulations commonly used by direct detection experiments, does not reproduce the measured spectrum below 0.5 keV. The data are in better agreement with ab initio calculations originally developed for x-ray absorption spectroscopy.The DAMIC-M project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme Grant Agreement No. 788137, and from NSF through Grant No. NSF PHY-1812654. The work at University of Chicago and University of Washington was supported through Grant No. NSF PHY-2110585. This work was supported by the Kavli Institute for Cosmological Physics at the University of Chicago through an endowment from the Kavli Foundation. We also thank the College of Arts and Sciences at UW for contributing the first CCDs to the DAMIC-M project. I. F. C. A. was supported by project PID2019–109829 GB-I00 funded by MCIN/ AEI /10.13039/501100011033. The Centro Atómico Bariloche group is supported by ANPCyT Grant No. PICT-2018-03069. The University of Zürich was supported by the Swiss National Science Foundation. The CCD development work at Lawrence Berkeley National Laboratory Microsystems Lab was supported in part by the Director, Office of Science, of the U.S. Department of Energy under Award No. DE-AC02-05CH11231. We thank Gerald T. Seidler for introducing us to the feff code, and thank Joshua J. Kas, Micah P. Prange, and John J. Rehr for their support with feff. We also thank Christian Sternemann for sharing his NRIXS silicon spectra
Sperm characteristics and in vitro fertilization ability of thawed spermatozoa from Black Manchega ram: Electroejaculation and postmortem collection
P. 160-168The aim of this study was to assess two models of sperm collection on the quality and fertility of thawed spermatozoa from Black Manchega rams, a threatened breed. Sperm samples were collected by electroejaculation and postmortem from each male. Samples were diluted with Biladyl and frozen. Motility (subjective and objective by means of computer-assisted semen analysis), membrane integrity, and acrosomal status (microscopy) were assessed on fresh and thawed semen; plasmalemma integrity, mitochondrial membrane potential, DNA integrity, and acrosomal status were evaluated by flow cytometry on thawed semen. Thawed spermatozoa were used in a heterologous in vitro fertilization test. After thawing, the proportion of live spermatozoa with intact membrane (YO-PRO-1−/PI−) was higher for postmortem samples (P < 0.001), although the ratio of YO-PRO-1− spermatozoa within the PI− population was higher for ejaculated samples (P = 0.007). Likewise, the proportion of live spermatozoa having high mitochondrial membrane potential (MitoTracker+) and intact acrosomes (PNA−) was higher for postmortem samples (P < 0.001 and P < 0.001, respectively). Considering only live spermatozoa, the ratio of MitoTracker+/PNA− cells was higher for electroejaculated samples (P = 0.026 and P = 0.003). Both electroejaculated and postmortem samples fertilized oocytes. Nevertheless, electroejaculated samples yielded a higher percentage of hybrid embryos (P = 0.041). In conclusion, although postmortem spermatozoa had better sperm quality after thawing, electroejaculated spermatozoa showed higher ratios for sperm quality when only the live population was considered. Electroejaculated and postmortem samples might be used for germplasm banking of this threatened breed, but the fertility of postmortem spermatozoa might be lower.S
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