6,285 research outputs found

    Unveiling the power spectra of δ\delta Scuti stars with TESS. The temperature, gravity, and frequency scaling relation

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    Thanks to high-precision photometric data legacy from space telescopes like CoRoT and Kepler, the scientific community could detect and characterize the power spectra of hundreds of thousands of stars. Using the scaling relations, it is possible to estimate masses and radii for solar-type pulsators. However, these stars are not the only kind of stellar objects that follow these rules: δ\delta Scuti stars seem to be characterized with seismic indexes such as the large separation (Δν\Delta\nu). Thanks to long-duration high-cadence TESS light curves, we analysed more than two thousand of this kind of classical pulsators. In that way, we propose the frequency at maximum power (νmax\nu_{\rm max}) as a proper seismic index since it is directly related with the intrinsic temperature, mass and radius of the star. This parameter seems not to be affected by rotation, inclination, extinction or resonances, with the exception of the evolution of the stellar parameters. Furthermore, we can constrain rotation and inclination using the departure of temperature produced by the gravity-darkening effect. This is especially feasible for fast rotators as most of δ\delta Scuti stars seem to be.Comment: 12 pages, 13 figures, accepted in Astronomy & Astrophysic

    Lower incisor position in different malocclusions and facial patter

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    Introduction: The position of lower incisor has been of considerable concern when planning an orthodontic treatment, having been recognized as one of diagnostic keys, Very important in the development of malocclusion and facial pattern. Objectives: In this study we claim to determine the importance of the position and inclination of lower incisor in the different malocclusions and facial patterns, and to base which of the cephalometric measurement parameters are the mostreliable. Material and Methods: Ninety lateral radiographies were taken, and they were classified by skeletal malocclusion and facial pattern.These teleradiographies have been performed cephalometric analysis, which includelower incisor position belong the following analysis: Ricketts, Riolo, Tweed, McHorris, Jarabak-MSE and Holdaway. Study Design: Cross-sectional study where we perform statistical analysis Anova test, Pearson correlations and Bonferroni analysis. Results: The analyzed measurements present a statistically significant differentiation in lower incisor inclination respect to the anterior cranial base, McHorris angle, angulation of lower incisor respect to occlusal plane and mandibular plane. Conclusions: There are statistically significant differentiation in lower incisor position and inclination respect the malocclusion and individual facial pattern

    Lower incisor position in different malocclusions and facial patterns

    Get PDF
    Introduction: The position of lower incisor has been of considerable concern when planning an orthodontic treatment, having been recognized as one of diagnostic keys, Very important in the development of malocclusion and facial pattern. Objectives: In this study we claim to determine the importance of the position and inclination of lower incisor in the different malocclusions and facial patterns, and to base which of the cephalometric measurement parameters are the mostreliable. Material and Methods: Ninety lateral radiographies were taken, and they were classified by skeletal malocclusion and facial pattern.These teleradiographies have been performed cephalometric analysis, which includelower incisor position belong the following analysis: Ricketts, Riolo, Tweed, McHorris, Jarabak-MSE and Holdaway. Study Design: Cross-sectional study where we perform statistical analysis Anova test, Pearson correlations and Bonferroni analysis. Results: The analyzed measurements present a statistically significant differentiation in lower incisor inclination respect to the anterior cranial base, McHorris angle, angulation of lower incisor respect to occlusal plane and mandibular plane. Conclusions: There are statistically significant differentiation in lower incisor position and inclination respect the malocclusion and individual facial pattern

    A simulation analysis of an influenza vaccine production plant in areas of high humanitarian flow. A preliminary study for the region of norte de santander (colombia)

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    The production of vaccines of biological origin presents a tremendous challenge for re-searchers. In this context, animal cell cultures are an excellent alternative for the isolation and production of biologicals against several viruses, since they have an affinity with viruses and a great capacity for their replicability. Different variables have been studied to know the system’s ideal parameters, allowing it to obtain profitable and competitive products. Consequently, this work fo-cuses its efforts on evaluating an alternative for producing an anti‐influenza biological from MDCK cells using SuperPro Designer v8.0 software. The process uses the DMEN culture medium supple-mented with nutrients as raw material for cell development; the MDCK cells were obtained from a potential scale‐up with a final working volume of 500 L, four days of residence time, inoculum volume of 10%, and continuous working mode with up to a total of 7400 h/Yr of work. The scheme has the necessary equipment for the vaccine’s production, infection, and manufacture with yields of up to 416,698 units/h. In addition, it was estimated to be economically viable to produce recom-binant vaccines with competitive prices of up to 0.31 USD/unit

    Reconstrucción de defectos óseos segmentarios postraumáticos mediante técnica de inducción de membrana

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    Objetivos: Describir y evaluar los resultados del tratamiento quirúrgico de defectos óseos postraumáticos (DOPT) segmentarios mediante técnica de inducción de membrana. Material y métodos: Estudio descriptivo longitudinal de 20 casos de DOPT segmentarios tratados en el Hospital Nacional Cayetano Heredia de Lima, desde enero de 2009 a junio de 2014, mediante reconstrucción en dos etapas con técnica de inducción de membrana. En la primera etapa se indujo la formación de membrana con un espaciador de cemento óseo impregnado con antibiótico. En la segunda etapa se reemplazó el espaciador por injerto óseo. Se evaluó el tiempo de consolidación, grado de acortamiento de la extremidad y resultado funcional. Se registraron las complicaciones. Resultados: Se incluyeron 20 pacientes (15 varones y 5 mujeres), con edad promedio de 29 años (rango: 13-54). Once casos fueron DOPT en tibia, 7 casos en fémur, uno en radio y uno en cúbito. El 90% de los DOPT fueron en longitud mayor o igual a 50 mm, con un promedio de 73 mm; 60% de los casos tenían cultivos positivos al inicio del tratamiento. Presentaron consolidación el 90% de los casos con un único aporte de injerto óseo, el tiempo promedio para la consolidación fue 8 meses. Uno requirió un segundo aporte de injerto y un caso presentó persistencia de infección sin consolidación. Conclusiones: La técnica de inducción de membrana es un método eficaz para el tratamiento de DOPT segmentarios

    Photovoice: An active learning tool with community nursing students

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    Objective: To assess nursing students’ experiences of using photovoice as a pedagogical approach to active learning in the community. Methods: A descriptive design with a cross-sectional mixed-method questionnaire was used with 108 students following an educational activity, in which their communities were photographed and the impact of the pandemic on vulnerable populations was reflected. Descriptive statistics and thematic analysis were used to analyze the data. Results: Seventy eight percent of the students felt that photovoice was an interesting and useful tool for nurses, 89% affirmed it helped stimulate reflection on social and health inequities in times of pandemic, 82% described that it developed many emotions and feelings and 86% would like to disseminate their photographs directly to stakeholders, citizens, and politicians. Three themes were identified in the data: “stimulate critical reflection”, “develop emotional skills”, and “encourage action”. Conclusions: Photovoice is a successful active learning pedagogical approach that engages nursing students to develop critical awareness while connecting with their communities, with the real world. It fosters students' sensitivity and motivation and encourages them to take action. Teachers need to introduce new scaffolds for active learning, such as photovoice, to provide innovative academic support that nurtures and develops the next generation of nurses appropriately

    AmericasNLI: Machine translation and natural language inference systems for Indigenous languages of the Americas

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    Little attention has been paid to the development of human language technology for truly low-resource languages—i.e., languages with limited amounts of digitally available text data, such as Indigenous languages. However, it has been shown that pretrained multilingual models are able to perform crosslingual transfer in a zero-shot setting even for low-resource languages which are unseen during pretraining. Yet, prior work evaluating performance on unseen languages has largely been limited to shallow token-level tasks. It remains unclear if zero-shot learning of deeper semantic tasks is possible for unseen languages. To explore this question, we present AmericasNLI, a natural language inference dataset covering 10 Indigenous languages of the Americas. We conduct experiments with pretrained models, exploring zero-shot learning in combination with model adaptation. Furthermore, as AmericasNLI is a multiway parallel dataset, we use it to benchmark the performance of different machine translation models for those languages. Finally, using a standard transformer model, we explore translation-based approaches for natural language inference. We find that the zero-shot performance of pretrained models without adaptation is poor for all languages in AmericasNLI, but model adaptation via continued pretraining results in improvements. All machine translation models are rather weak, but, surprisingly, translation-based approaches to natural language inference outperform all other models on that task

    Asteroseismic analysis of the CoRoT \delta-Scuti star HD174936

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    We present an analysis of the \delta-Scuti star object HD 174936 (ID 7613) observed by CoRoT during the first short run SRc01 (27 days). A total number of 422 frequencies we are extracted from the light curve using standard prewhitening techniques. This number of frequencies was obtained by considering a spectral significance limit of sig = 10 using the software package SigSpec. Our analysis of the oscillation frequency spectrum reveals a spacing periodicity of around 52 \muHz. Although modes considered here are not in the asymptotic regime, a comparison with stellar models confirms that this signature may stem from a quasi-periodic pattern similar to the so-called large separation in solar-like stars.Comment: 7 pages, 7 figures, 2 tables. Accepted for publication in A&A CoRoT Special Featur

    Climatic groups in Ibero-America viticulture compared to worldwide wine producer regions.

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    The wine production is an important activity in many Ibero-American countries. The wine producer regions of these countries configure a large use of different climate types and viticultural climates. In a vitivinicultural zoning project of CYTED (Ibero-American Program for Science, Technology and Development), a viticultural climatic characterization was done in this macro viticultural region. The project have assembled a climatic database that characterizes the viticultural regions, including relevant variables for viticulture: air temperature (mean, maximum, and minimum), precipitation, relative humidity, solar radiation, number of sunshine hours, wind speed, and evapotranspiration. Using indices of the Geoviticulture MCC System (HI, CI and DI), more than 70 viticultural regions in different countries (Argentina, Bolivia, Brazil, Chile, Cuba, Spain, Mexico, Peru, Portugal and Uruguay) were characterized according to its viticultural climatic. The results, which will be integrated to the worldwide database of the MCC System, showed that the Ibero-American viticulture is placed in a wide range of climatic groups of the wine producing regions around the world. This article presents the climatic groups found in Ibero-America, identifying also some new climatic groups not yet found in other regions of the world. This work also identifies some climatic groups not found in Ibero-America viticulture. The research has also highlighted viticultural areas characterized by climates with ?intra-annual climatic variability?, with the potential to produce more than one growing cycle per year. The results allow to conclude that the wide variability and climatic diversity present in Ibero-America may be one of the reasons to explain the diversity in terms of wine types, sensorial characteristics, typicity and uniqueness of wines produced on this macro-region
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