Exploring perceptions of extreme environments and extremophiles in Chilean schoolchildren: an ethnographic study.

Chile is unique because of its diverse extreme environment, ranging from arid climates in the north to polar climates in Patagonia. Microorganisms that live in these environments are called extremophiles, and these habitats experience intense ecosystem changes owing to climate warming. Most studies of extremophiles have focused on their biotechnological potential; however, no study has examined how students describe extremophiles. Therefore, we were interested in answering the following question: How do schoolchildren living in extreme environments describe their environments and extremophiles? We performed an ethnographic study and analyzed the results of 347 representative drawings of participants aged 12-16 years from three schools located in the extreme environments of Chile San Pedro de Atacama (hyper-arid, 2,400 m), Lonquimay (forest, 925 m), and Punta Arenas (sub-Antarctic, 34 m). The social representation approach was used to collect data, and systemic networks were used to organize and systematize the drawings. The study found that, despite differences between extreme environments, certain natural elements, such as trees and the sun, are consistently represented by schoolchildren. The analysis revealed that the urban and rural categories were the two main categories identified. The main systemic networks were rural-sun (21,1%) for hyper-arid areas, urban-tree (14,1%) for forest areas, and urban-furniture (23,4%) for sub-Antarctic areas. When the results were analyzed by sex, we found a statistically significant difference for the rural category in the 7th grade, where girls mentioned being more rural than boys. Students living in hyper-arid areas represented higher extremophile drawings, with 57 extremophiles versus 20 and 39 for students living in sub-Antarctic and forest areas, respectively. Bacteria were extremophiles that were more represented. The results provide evidence that natural variables and semantic features that allow an environment to be categorized as extreme are not represented by children when they are focused on and inspired by the environment in which they live, suggesting that school literacy processes impact representations of their environment because they replicate school textbooks and not necessarily their environment.

Rheological Method for Determining the Molecular Weight of Collagen Gels by Using a Machine Learning Technique.

This article presents, for the first time, the results of applying the rheological technique to measure the molecular weights (Mw) and their distributions (MwD) of highly hierarchical biomolecules, such as non-hydrolyzed collagen gels. Due to the high viscosity of the studied gels, the effect of the concentrations on the rheological tests was investigated. In addition, because these materials are highly sensitive to denaturation and degradation under mechanical stress and temperatures close to 40 °C, when frequency sweeps were applied, a mathematical adjustment of the data by machine learning techniques (artificial intelligence tools) was designed and implemented. Using the proposed method, collagen fibers of Mw close to 600 kDa were identified. To validate the proposed method, lower Mw species were obtained and characterized by both the proposed rheological method and traditional measurement techniques, such as chromatography and electrophoresis. The results of the tests confirmed the validity of the proposed method. It is a simple technique for obtaining more microstructural information on these biomolecules and, in turn, facilitating the design of new structural biomaterials with greater added value.

Augmented reality-based learning for the comprehension of cardiac physiology in undergraduate biomedical students.

The integrated mechanisms of heart contraction are some of the most complex processes for undergraduate biomedical students to understand. Visual models have the potential to enhance learning environments by providing visual representations of complex mechanisms. Despite their benefits, the use of visual models in undergraduate classrooms is still limited. For this study, we tested the effect of a learning sequence of activities related to the cardiac cycle using an augmented reality (AR) application for smartphones and tablets. We were interested in understanding the ability of students to draw and label figures reflecting cardiac function after experiencing the learning sequence using AR. Undergraduate students of the biomedical sciences (control n = 43, experimental n = 58) were enrolled in the course, and their drawings were evaluated using multiple levels of complexity (1 = basic to 5 = complex) through a pre-/posttest structure that included a learning sequence based on AR in the experimental group and regular lecture-based activities in the control group. The complexity of students' drawings was evaluated on the anatomical, physiological, and molecular aspects of heart contraction. We used Cohen's kappa index for interrater reliability when determining the complexity of drawings. Control and experimental groups showed no differences in baseline knowledge (preexamination quiz). The students who experienced the AR activities showed an increase in the complexity of representation levels in posttest results and also showed a significant difference in scores for the final exam in the heart physiology course. Our results indicate that using AR enhances the comprehension of anatomical and physiological concepts of the cardiac cycle for undergraduate biomedical students.

Learning Human Anatomy Using Three-Dimensional Models Made from Real-Scale Bone Pieces: Experience with the Knee Joint among Pre-Service Biology Teachers / Aprendizaje de la Anatomía Humana Utilizando Modelos Tridimensionales a Escala: Experiencia con la Articulación de Rodilla en Profesores de Biología en Formación

This study aims to assess the efficiency of using real-scale knee models to learn about the locomotor system. Participants included a total of thirty-nine second year students in a Human Anatomy class of a Biology Teaching course. One week before the intervention, a pre-test was administered to assess the students' prior knowledge. The pre-service biology teachers were provided with a real-scale plaster model of a knee bone and were subsequently required to identify and create their own model of bone, joint and muscle elements. At the end of the intervention, a post-test was performed and opinion survey, in addition to a comparison with other locomotor system structures (four images: knee joint, muscular component of lower limb, shoulder joint and pelvic bone). Students' scores increased significantly in relation to the pre-test, both among the total sample (P=0.000) and between sub-groups divided according to participant gender (male P=0.0021; female P=0.0005) as well as compared to other structures (P<0.05). Furthermore, the pre-service biology teachers showed significant increases in their scores on a Likert-type opinion survey, indicating that these types of interventions promote their motivation for the course (89.2%) as well as their learning (97.8%) and would be advisable for future students (95.5%). The results show that the use of real-scale models and associated work fosters student motivation and enhances the learning of human anatomy.

El objetivo fue evaluar la eficacia de utilizar modelos de rodilla a escala real para el aprendizaje del sistema locomotor. Los participantes incluyen un total de treinta y nueve estudiantes de segundo año de un curso de anatomía humana para estudiantes de Pedagogía en Biología y Ciencias Naturales. Una semana antes de la intervención, se administró un pre-test para evaluar los conocimientos previos de los alumnos. Luego a los profesores de biología en formación se les proporcionó un modelo de yeso a escala real de los huesos de la rodilla donde se les solicitó identificar y crear su propio modelo de elementos de huesos, articulaciones y músculos. Al final de la intervención, se realizó un post-test y una encuesta de opinión, además de una comparación con otras estructuras del aparato locomotor (cuatro imágenes: articulación de la rodilla, componente muscular del miembro inferior, articulación del hombro y el hueso de la pelvis). Los puntajes de los estudiantes aumentaron significativamente en relación con el pre-test, tanto en la muestra total (P= 0,000) y entre subgrupos divididos de acuerdo al sexo (P= 0,0021 masculino; p= 0,0005 femenino), así como también en comparación con otras estructuras del aparato locomotor (P<0,05). Por otra parte, los profesores de biología en formación mostraron altas puntuaciones en una encuesta de opinión tipo Likert, indicando que este tipo de intervenciones promueven su motivación para el curso (89,2%), así como su aprendizaje (97,8%) y que serían recomendable para los futuros estudiantes (95,5%). Los resultados muestran que el uso de modelos a escala real fomenta la motivación del estudiante y mejora el aprendizaje de la anatomía humana.

Evaluación de la percepción del proceso de enseñanza y aprendizaje de un curso de morfología humana por parte de estudiantes de un programa para talentos académicos / Evaluation of the teaching and learning process in a human morphology course by students from an academic talents program

La alta capacidad intelectual se considera una manifestación diferencial del desarrollo cognitivo, siendo la estimulación temprana y sistemática favorecedores de su expresión y desarrollo. Es por ello, que otorgar oportunidades educativas enriquecidas es central para los los niños y niñas con talentos académicos. Esta investigación evalúa la percepción de los estudiantes frente a una metodología de enseñanza teórico-práctica en un curso dirigido a talentos académicos de enseñanza media (n=17) en el área de morfología humana. Los estudiantes formaron parte de un programa universitario de enriquecimiento extracurricular. Al final del periodo los estudiantes evaluaron los cursos mediante una encuesta referida a: i) el curso ii) el profesor, y iii) autoevaluación. Los resultados de la comparación de las evaluaciones realizadas por los estudiantes que participaron en dicho curso versus estudiantes de otros cursos (n=128) muestran diferencias significativas (p<0,05). El talento académico que presenta este tipo de estudiantes complementado con la metodología de trabajo aplicada, permite que avancen secuencialmente y acorde a sus capacidades, en un ambiente de trabajo propicio para tal desarrollo. Además, este tipo de intervenciones fomenta el estudio de la morfología humana en estudiantes con talento académico.

High intellectual capacity is considered to be a differential characteristic of cognitive development, noting that early and systematic stimuli encourages its expression and advancement. It is therefore, essential for academically talented children to be given enriched educational opportunities. This research project evaluates the students perceptions in a theoretical-practical teaching methodology in a course directed at high school academic talents in the area of human morphology. The students were part of a university program for extra-curricular enrichment. At the end of the period, the students assessed the courses by means of a survey referred to: i) the course ii) the professor and iii) self-evaluation. The results taken from the comparisons of the evaluations of the students participating in the course versus the students from other courses (n=128) showed significant differences (p<0.05). The academic talent represented by this type of student, complemented with the applied work methodology, allows the students to sequentially progress according to their capacities in an appropriate work environment for their development. Furthermore, it also encourages human morphology study in students who are academically talented.