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Aprender con sentido en educación inicial: una mirada a la metodologÃa de proyecto
Get PDFEl presente ensayo contiene una reflexión sobre la importancia de llevar a cabo metodologÃas activas en educación inicial, que reconozcan y valoren las caracterÃsticas propias de este nivel educativo, visibilizando las demandas de la infancia respecto a cómo se deben desarrollar los procesos de enseñanza y aprendizaje. Asimismo, se describe la metodologÃa de proyecto como una opción educativa que promueve los principios, fundamentos y enfoques de la educación parvularia, dando sentido al aprendizaje y al rol formador que deben desempeñar los párvulos como verdaderos protagonistas de su aprendizaje
Field-based learning in global migrant health: An evaluation of student learning outcomes
No full textIncreased migration and im/migrant (i.e. migrant and immigrant) inequities, particularly during COVID-19, call for experiential global public health teaching to adequately prepare future leaders. We evaluated student perspectives on the benefits, drawbacks, and lessons learned from a migrant health field course in the U.S.Mexico border region. We analyzed qualitative data from reflexive diary-writing assignments and post-course evaluations from graduate and undergraduate students (N = 12). Students highlighted personal growth and reflexivity, professional development opportunities, and benefits and drawbacks of the immersive course design as key themes. Tri-national learning across Canada, Mexico and the U.S., and an interdisciplinary, cross-cultural learning model allowed for deeper understandings of globally relevant and politically and socially complex issues through community engagement and `real-world' approaches. Students described benefits of reflexive learning, bridging classroom-based learning with field experiences, and learning about community-engaged research in advancing im/migrant justice, though acknowledged challenges of intensive course design. Narratives highlighted unique needs in navigating challenges inherent in reflexive learning on sensitive topics, such as structural inequities faced by asylum seekers. This evaluation provides unique empirical evidence to inform future experiential learning opportunities rooted in equity-oriented approaches, which are crucial for advancing hands-on learning regarding global issues. Appropriate approaches must ensure ethical, respectful community engagement and ongoing support for students.This work was supported by the Simon Fraser University [Teaching & Learning Centre [G0263]]
Adenomatoid Odontogenic Tumor Associated To Reactive Fibro Osseous Lesion: A Case Report
No full textAn adenomatoid odontogenic tumor (AOT) is a benign epithelial lesion, being the fourth most common among all odontogenic tumors. Usually presents as slow painless growth that sometimes leads to facial asymmetry. Many cases are detected by radiographic studies, and the indication for biopsy and surgery is secondary to this finding. We report a case of a 17-year-old man with a history of left mandibular painless swelling since 4 months ago, associated with facial asymmetry and hard consistency. An imaging study showed an extensive unilocular radiolucent lesion to the basilar arch, with defined limits and with peripheral hyperdense areas located only vestibular to the lesion. The histopathology was composed of odontogenic epithelial cell proliferation, with epithelial nodular and duct-like structures, rosettes of spindled epithelial cells with eosinophilic material, calcifications, and fibro-osseous reaction. Surgical conservative excision including the affected tooth is the treatment of choice and recurrence is rare. The histologic findings of reactive fibro-osseous proliferation in AOT should be interpreted as a reactive change in the tumor capsule and not as an adnexal lesion. We present an atypical case of AOT with reactive fibro-osseous reaction. Despite clinical aggressive behavior, conservative surgical treatment could be the treatment of choice. Additionally, we emphasize the importance of histopathological examination together with the imaging study of radiolucent lesions of the maxillary bones. Key words:Adenomatoid Odontogenic Tumor, Odontogenic tumor, fibro-osseous lesion
Complications Of Tattoos: Literature Review
No full textEl tatuaje se define como la implantación de un pigmento exógeno en la dermis para crear un diseño. Mayoritariamente los tatuajes son decorativos, pero también pueden ser con fines religiosos, médicos u ocurrir accidentalmente. La Academia Americana de DermatologÃa distingue 5 tipos de tatuajes: traumáticos, amateurs, profesionales, médicos y cosméticos. Los tatuajes son tan antiguos como la humanidad, datan de hace 5.300 años. Lo prueban los restos encontrados en los Alpes Italianos
Modelo de classificacao do agente avaliador segundo as relacoes de poder: o que avalia quem avalia
No full textLa clasificación tradicional de la evaluación según agentes evaluadores exige una reconfiguración a la luz del estudio de las relaciones de poder en las prácticas y las necesidades pedagógicas de proyectos innovadores. Se propone un nuevo modelo basado en la concepción de que lo que define el tipo de evaluación no es el rol del sujeto (docente, estudiante), sino la posición simbólica del evaluador respecto de lo evaluado, expresada en relaciones de poder y diálogo. El nuevo modelo considera los conceptos habituales categorizados según la naturaleza del evaluador: observador (heteroevaluación) y participante (coevaluación y autoevaluación). El artÃculo se organiza secuencialmente en problematización, revisión de la teorÃa evaluativa, análisis del modelo de clasificación tradicional y descripción del modelo propuesto
The autophagy protein Def8 is altered in Alzheimer's disease and Aβ42-expressing Drosophila brains
No full textAlzheimer's disease (AD) is the most common neurodegenerative disorder, characterized by protein accumulation in the brain as a main neuropathological hallmark. Among them, A beta 42 peptides tend to aggregate and create oligomers and plaques. Macroautophagy, a form of autophagy characterized by a double-membrane vesicle, plays a crucial role in maintaining neuronal homeostasis by degrading protein aggregates and dysfunctional organelles as a quality control process. Recently, DEF8, a relatively uncharacterized protein, has been proposed as a participant in vesicular traffic and autophagy pathways. We have reported increased DEF8 levels in lymphocytes from mild cognitive impairment (MCI) and early-stage AD patients and a neuronal profile in a murine transgenic AD model. Here, we analyzed DEF8 localization and levels in the postmortem frontal cortex of AD patients, finding increased levels compared to healthy controls. To evaluate the potential function of DEF8 in the nervous system, we performed an in silico assessment of its expression and network profiles, followed by an in vivo evaluation of a neuronal Def8 deficient model using a Drosophila melanogaster model of AD based on A beta 42 expression. Our findings show that DEF8 is an essential protein for maintaining cellular homeostasis in the nervous system, and it is upregulated under stress conditions generated by A beta 42 aggregation. This study suggests DEF8 as a novel actor in the physiopathology of AD, and its exploration may lead to new treatment avenues.We thank Washington University, Knight ADRC (Alzheimer's Disease Research Center), grants number P50AG005681, P01AG003991, and P01AG026276, for donating human brain samples. This study used fly stocks obtained from the Bloomington Drosophila Stock Center (NIH P40OD018537). All the biosafety and approvals for the ethical were obtained before the start of the study. All procedures performed in this study were under the ethical standards of the University Mayor. The study was conducted following the Bioethical Scientific Committee from Universidad Mayor Protocol. This work was directly funded by the Chilean Government grants Fondecyt 11200981 (MS) and FDP-UM2021-34 (MS), Fondecyt 1200459 (UW), Fondecyt 1230823 (DRR-MS), FONIS SA22I0041 (NS), and Fondecyt 11160288 (MCN)
Vinificación y guarda de vinos Carignan en tinajas de arcilla de Pañul: estudio de la composición volátil de los vinos
No full textClay vessels have been used since several times to vinification and aging wines. Currently, wine producers have returned to use traditional production methods to provide differentiate attributes and increase the wine typicity. The goal of this research was to study the volatile compounds of Carignan wines a) vinified in stainless steel tanks and aged in Panul's pottery vessels, and b) vinified and aging in Panul's pottery vessels. The results showed that the content of 1-hexanol, 2,3-butanediol, and alpha-terpinol was higher in wines vinified in stainless steel tanks and ageing in Panul's pottery vessels, while the content of 1-heptanol, butanoic acid, hexanoic acid and 0-damascenone was higher in wines vinified and aged in Panul's pottery vessels. Carignan wines aged in Panul's pottery vessels presented aromatic attributes such as floral, fruity, citrus, almond, green apple, strawberry, and anise according to their odorant activity value. These results may be of interest to ceramic and wine producers, as they open a range of economic opportunities by diversifying their products
Climate variability of the southern Amazon inferred by a multi-proxy tree-ring approach using Cedrelafissilis Vell
No full textThe analysis of climate variability and development of reconstructions based on tree-ring records in tropical forests have been increasing in recent decades. In the Amazon region, ring width and stable isotope long-term chronologies have been used for climatic studies, however little is known about the potential of wood traits such as density and chemical concentrations. In this study, we used well-dated rings of Cedrela fissilis Vell. from the drought-prone southern Amazon basin to assess the potential of using inter-annual variations of annually-resolved ring width, wood density, stable oxygen isotope (818OTR) measured in tree-ring cellulose and concentration of Sulfur (STR) and Calcium (CaTR) in xylem cells to study climate variability. During wet years, Cedrela fissilis produced wider and denser rings with higher CaTR and lower STR, as well as depleted 818OTR values. During dry years, a wider range of responses was ob-served in growth, density and STR, while lower CaTR and enriched 818OTR values were found. The annual centennial chronologies spanning from 1835 to 2018 showed good calibration skills for reconstructing local precipitation, evapo-transpiration (P-PET), Amazon-wide rainfall, as well as climate modes related to sea surface temperature (SST) anom-alies such as El Nino South Oscillation (ENSO), Tropical Northern Atlantic (TNA), and the Western Hemisphere Warm Pool (WHWP) oscillations. CaTR explained 42 % of the variance of local precipitation (1975-2018), RW explained 30 % of the P-PET variance (1975-2018), while 818OTR explained 60 % and 57 % of the variance of Amazon rainfall (1960-2018) and El Nino 3.4 (1920-2018), respectively. Our results show that a multi-proxy tropical tree-ring ap-proach can be used for high-reliable reconstructions of climate variability over Amazon basin at inter-annual and multidecadal time scales.We thank the Wood Anatomy and Tree-Ring Laboratory (LAIM)(FAPESP project: 2009/53951-7), Department of Forest Sciences, Luiz deQueiroz College of Agriculture (ESALQ). This research was supported by the Post-Graduate Program of Forest Resources (ESALQ-USP, Brazil), and FAPESP grants 2020/04608-7, 2018/22914-8 and 2017/50085-3. RSS was supported by VULBOS project (UPO-1263216), VURECLIM(P20_00813) and AH by PinCaR project (UHU-1266324) both by FEDER Funds, Andalusia Regional Government, Consejeria de Economia, Conocimiento, Empresas y Universidad 2014-2020. RSS and AH were also supported by EQC2018-004821-P and IE19_074 UPO projects co funded by Spanish "Plan Estatal de Investigacion Cientificay TecnicaydeInnovacion 2017-2020" and "Plan Andaluz de Invetigacion, Desarrollo e Innovacion (PAIDI 2020)", respectively. GAP was supported by CAPES (grant #88887.199858/2018-00) in the National Academic Cooperation Programin the Amazon. Additional thanks to the logging company AMATA for their assistance in the field work
High-accuracy detection of supraspinatus fatty infiltration in shoulder MRI using convolutional neural network algorithms
No full textBackgroundThe supraspinatus muscle fatty infiltration (SMFI) is a crucial MRI shoulder finding to determine the patient's prognosis. Clinicians have used the Goutallier classification to diagnose it. Deep learning algorithms have been demonstrated to have higher accuracy than traditional methods. AimTo train convolutional neural network models to categorize the SMFI as a binary diagnosis based on Goutallier's classification using shoulder MRIs. MethodsA retrospective study was performed. MRI and medical records from patients with SMFI diagnosis from January 1st, 2019, to September 20th, 2020, were selected. 900 T2-weighted, Y-view shoulder MRIs were evaluated. The supraspinatus fossa was automatically cropped using segmentation masks. A balancing technique was implemented. Five binary classification classes were developed into two as follows, A: 0, 1 v/s 3, 4; B: 0, 1 v/s 2, 3, 4; C: 0, 1 v/s 2; D: 0, 1, 2, v/s 3, 4; E: 2 v/s 3, 4. The VGG-19, ResNet-50, and Inception-v3 architectures were trained as backbone classifiers. An average of three 10-fold cross-validation processes were developed to evaluate model performance. AU-ROC, sensitivity, and specificity with 95% confidence intervals were used. ResultsOverall, 606 shoulders MRIs were analyzed. The Goutallier distribution was presented as follows: 0 = 403; 1 = 114; 2 = 51; 3 = 24; 4 = 14. Case A, VGG-19 model demonstrated an AU-ROC of 0.991 +/- 0.003 (accuracy, 0.973 +/- 0.006; sensitivity, 0.947 +/- 0.039; specificity, 0.975 +/- 0.006). B, VGG-19, 0.961 +/- 0.013 (0.925 +/- 0.010; 0.847 +/- 0.041; 0.939 +/- 0.011). C, VGG-19, 0.935 +/- 0.022 (0.900 +/- 0.015; 0.750 +/- 0.078; 0.914 +/- 0.014). D, VGG-19, 0.977 +/- 0.007 (0.942 +/- 0.012; 0.925 +/- 0.056; 0.942 +/- 0.013). E, VGG-19, 0.861 +/- 0.050 (0.779 +/- 0.054; 0.706 +/- 0.088; 0.831 +/- 0.061). ConclusionConvolutional neural network models demonstrated high accuracy in MRIs SMFI diagnosis