1,479 research outputs found
An efficient protocol to perform genetic traceability of tissue and foods from Geoffroea decorticans
The quality of a DNA isolation method depends, among others, on the target tissue and the metabolites therein. Geoffroea decorticans Burkart (chanar) is a species that has nutritional and pharmacological potential. However, an effective method of DNA extraction capable of facilitating population studies and food genetic traceability has not been studied yet. The objective of the present work was to evaluate four methods of DNA extraction from leaves and chanar-based foods. The methods were evaluated based on yield, DNA purity, and molecular markers. The CCI-P (CTAB/Chloroform-Isoamylalcohol/pellet) method showed the highest yield of DNA obtained from leaves. However, the CPCI-SC (CTAB/Phenol-Chloroform-Isoamylalcohol/silica-column) method was the only one that resulted in acceptable DNA quality with both parameters (A260/A280 and A260/A230). The leaf DNA obtained with this method showed a greater amount of fragments with RAPD, and an acceptable amount of fragments with ISSR. On the other hand, the CCI-P method showed a higher yield of DNA from arrope de chanar (syrup). However, the CPCI-SC method was the only one that had relatively better DNA quality, which allowed the amplification of molecular markers. Regarding chanar flour, the CPCI-SC method showed the highest yield, DNA quality and good amplification with molecular markers. Therefore, the CPCI-SC extraction method is efficient for obtaining DNA from different matrices, and can support studies for a possible designation of origin of chanar-based foods
Creativity, pedagogical, and educational innovation: analysis of the perception of a group of Chilean teachers
Este estudio se circunscribe al ámbito de la educación, la didáctica y la metodología en el trabajo de aula. Se analizan los resultados de una investigación con enfoque cuantitativo, que tuvo por objetivo identificar la percepción y experiencias acerca de la creatividad, innovación pedagógica y educativa -estas dos últimas nociones no siempre claras y distinguibles en la teoría y los estudios empíricos- en un grupo de docentes que recién inicia su proceso de formación en un programa de postgrado de Magíster en Didáctica, dictado por la Escuela de Educación del Campus Los Ángeles de la Universidad de Concepción, de la provincia y región de Biobío, Chile. La investigación tuvo un alcance descriptivo y como principal técnica de recolección de datos se utilizó un cuestionario de opinión con preguntas abiertas. Los principales hallazgos señalan que el profesorado en general y en un porcentaje mayoritario valora la creatividad, entiende el concepto de innovación pedagógica, pero tiene dificultades para identificar la diferencia entre esta última y la innovación educativa debido a su amplitud conceptual. Además, los resultados señalan que si bien el profesorado cree que la innovación es necesaria y tiene buena predisposición a ella en el ámbito de su labor pedagógica-docente, no siempre se generan las condiciones favorables para su implementación en los establecimientos educativos.This study is circumscribed to the scope of education, didactics, and classroom methodology. The results of an investigation with a quantitative approach will be analyzed, whose aim was to identify the perception and experiences related to creativity, as well as to pedagogical and educational innovation - the two latter concepts not always clear and distinguishable in theory and empirical studies. The research was done in a group of teachers who were just beginning their training process in a Graduate Degree in Didactics, taught in the School of Education at the Los Angeles Campus of the Universidad de Concepción, in the region of Biobío, Chile. The investigation had a descriptive approach and the main method for data collection was an opinion questionnaire with open questions. The main findings show that teachers in general and in a high percentage appreciate creativity, understand the concept of pedagogical innovation, but have difficulties to identify the difference between the latter and educational innovation due to its conceptual breadth. Furthermore, the results show that while teachers believe that innovation is necessary and that they are willing to do it in their pedagogical teaching activity, favorable conditions to implement it in schools are not always generated
Multi-epoch <i>L</i>-band Spectroscopy of the Be Star μ Centauri Prior to Outburst
With the aim of contributing to the understanding of the disk formation process in Be stars, we pursued a one-year spectroscopic observing campaign of the Be star μ Centauri in the L-band, using VLT/ISAAC. We present the nine near-IR spectra we obtained in an epoch of relative photometric quiescence prior to an outburst of ΔV = 0.4 magnitude. Visual estimates during the epoch of our L-band spectroscopy are also presented for the first time, together with the unpublished complete visual light curve between the years 1998 and 2014. We observe significant and monotonic changes in emission line strength of Bracket-α and Pfund-γ lines relative to Humphreys lines, and also in the continuum slope. We interpret these observed changes in terms of important changes to the column density of the line emitting regions, moving from an optically thin to an optically thick stage just prior to a major outburst. For each observing date, we provide estimates for the column density and relative extension of the line emitting region. If the changes observed toward the end of our observing campaign were related to mass-loss changes from the central star, they would correspond to an increase in a factor of two in the mass of the disk in the innermost region. If related to the visual outburst observed one month later, the variability observed in our spectra would be the first detection of the early disk formation process in the L-band.Instituto de Astrofísica de La PlataFacultad de Ciencias Astronómicas y Geofísica
Sequential Monte Carlo with transformations.
This paper examines methodology for performing Bayesian inference sequentially on a sequence of posteriors on spaces of different dimensions. For this, we use sequential Monte Carlo samplers, introducing the innovation of using deterministic transformations to move particles effectively between target distributions with different dimensions. This approach, combined with adaptive methods, yields an extremely flexible and general algorithm for Bayesian model comparison that is suitable for use in applications where the acceptance rate in reversible jump Markov chain Monte Carlo is low. We use this approach on model comparison for mixture models, and for inferring coalescent trees sequentially, as data arrives
Mineralizaciones de hierro en el travertino de Lanjarón (Granada)
Las mineralizaciones de hierro y manganeso del travertino de Lanjarón (Granada) están constituídas fundamentalmente por goethita y ferrihidrita, junto a hidróxidos amorfos de hierro y óxidos de manganeso. El travertino esencialmente calcítico contiene eventualmente aragonito.El depósito de estos materiales está relacionado con el quimismo de las aguas minero-medicinales de la zona; así como, con la presencia de bacterias de los géneros Gallionella y Leptothrix
Patient Perceptions of Trauma-Focused Telemental Health Services Using the Telehealth Satisfaction Questionnaire (TSQ)
Telehealth services can address many barriers to traditional office-based mental health services. Few studies have assessed youth and caregiver perceptions of and satisfaction with trauma-focused interventions delivered via telemental health. The current study presents data collected using the Telehealth Satisfaction Questionnaire (TSQ), which was developed to measure child and caregiver satisfaction with services, comfort with the telehealth equipment, and barriers to traditional office-based services. Thirteen clinicians delivered home- and school-based Trauma-Focused Cognitive Behavioral Therapy (TF-CBT) via videoconferencing on tablets and computers to 60 child patients (71.7% Latinx, 18.3% Black, and 10.0% non-Hispanic White). Patients and caregivers completed the TSQ at treatment discharge via telephone, videoconferencing, or in-person interviews. There was a high level of satisfaction among patients and caregivers receiving TF-CBT via telemental health. Furthermore, most youth and caregivers felt comfortable using the telehealth equipment from the outset of therapy, and all participants who were not initially comfortable using the equipment reported feeling more comfortable over time. The most common barriers to traditional office-based services were caregiver work schedule (57.7%), distance to mental health clinic (55.8%), and lack of transportation (44.2%). Patients and caregivers expressed a preference for telemental health services if given the option between receiving therapy via videoconferencing versus going to an office-based clinic. Findings indicated telemental health treatment addressed barriers that would have otherwise prevented families from accessing office-based services. The Telehealth Satisfaction Questionnaire can be used to help clinics and providers assess patient and caregiver satisfaction with telehealth services in various settings
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