[Objective] The objective of this research focuses on developing competencies in artificial intelligence and machine learning for students wishing to experiment in the creation of machine learning models. [Methodology] The study was conducted in the Digital Image Processing Laboratory of Universidad Nacional de Costa Rica, during the first cycle of 2023 by faculty and students doing their internships. For this exploratory-applied research, a step-by-step methodology was created and used to classify benign and malignant mammograms by developing a machine-learning model. A data set comprised of 118 previously diagnosed mammogram images was used. [Results] Results are divided into two areas. The first area is the systematization of the teaching and learning process based on competencies, learning results, and the rubric to evaluate learning in artificial intelligence, machine learning, and neural networks. The second area involves the products generated by developing the computer application Mammography Classification Model, which integrates a convolution neural network that includes image transformation, creation, and training. [Conclusions] It is concluded that, in the academic field, student-centered learning models can be innovated to strengthen skills that enhance their professional profile. In the medical field, the classification of mammograms is an opportunity to develop competencies in a real environment.

[Objective] The paper aimed to evaluate in vitro development of infective structures of Beauveria spp. strains and their effect on the growth of tomato seedlings (Solanum lycopersicum) under high-temperature conditions. [Methodology] The development of five strains was compared under both optimal and high-temperature conditions (up to 35°C) regarding the production of conidia, mycelium growth, and germination. Subsequently, the effect of the strain with the highest yield on the growth of seedlings of S. lycopersicum, cultivar 'Gladiator', was assessed under the same temperature conditions. Furthermore, each strain was identified using PCR amplification of the nuclear intergenic region Bloc and elongation factor EF1-α. [Results] Strains were identified as Beauveria bassiana of neotropical lineage. No significant differences were found in the conidia production between treatments (p-value > 0.05), as opposed to mycelial growth. Minor but significant changes were observed in root-to-surface ratios but not in any other evaluated variables, and only for seedlings treated with strain H-31. [Conclusions] The entomopathogenic potential of B. bassiana was determined under environmental stress conditions, such as high temperatures typical of tropical climates. This study also lays the groundwork for the bioprospecting of thermotolerant microorganisms with agrobiotechnological potential in global warming scenarios.

[Objective] This study aimed to identify the knowledge, attitudes, and competences of second-cycle students from Excelencia Cahuita Elementary Coastal Public School, located in Limón, Costa Rica, for disaster risk management related to climate change, where there is a problem due to the impact on natural resources and the human environment. [Methodology] An exploratory-descriptive quantitative approach was used, with a non-experimental cross-sectional research design. The sample is non-probabilistic purposive and is represented by 52 fourth-, fifth-, and sixth-graders. The technique for data collection was a survey, therefore; a questionnaire was administered with 68 items distributed in five sections: 1. Respondent’s profile and characteristics; 2. knowledge of weather, climate, and climate change concepts; 3. climate change perception; 4. statements on disaster risk management (DRM); 5. identification of concepts related to the study of nature. [Results] Results show that reality is unfavorable to climate risk management in the subject of study; this unfavorable climate risk management is reflected in a deficient response and rescue training related to activities such as planning, logistical capability, and training through drills. [Conclusions] It is concluded that there is a need to generate environmental education plans that propose precise concepts on global warming, climate change, and disaster risk management. These concepts must be connected to daily life experiences recreated in the classroom to effectively address their complexity and allow children to be competent, adaptable, and resilient in the face of both adversities and benefits of climate change.

[Objective] This study aimed to implement 3D image acquisition and postprocessing tools for the natural heritage preservation of a collection of craniums from a zoology museum and a wildlife rescue center. [Methodology] Samples were prepared following osteotechnics protocols developed at the rescue center. They were then digitized in a darkroom using a metrology-grade 3D scanner. Meshes were optimized for both fabrication and visualization purposes. Subsequently, some of the models were printed at a university makerspace using three different technologies to be measured and analyzed with the metrology capabilities of inspection software; the purpose was to determine which technology provided the most accurate replicas.[Results] The results demonstrated that the three technologies produced high-quality replicas. However, those based on optical processes (SLA and material jetting) generated more accurate physical models, which are of particular interest for scientific fields, such as zooarchaeology, paleontology, biology, and veterinary medicine. These fields could benefit from training and learning experiences supported by these digital asset collections. The models were successfully adapted to be uploaded to a 3D viewer platform, which is compatible with low-cost virtual reality solutions, to implement them in environmental education activities. [Conclusions] The experience demonstrates that photogrammetry and 3D scanning are feasible solutions to preserve high-value samples of scientific and historical interest composed of biological materials exposed to degradation by environmental conditions. It also provides new digital assets to foster outreach and educational activities for universities, museums, and rescue centers.

[Objective] This study aimed to assess the production of basidiomata of Favolus rugulosus under controlled conditions in different mushroom-growing substrates and to analyze the proximate composition of cultivated basidiomata. [Methodology] The species was identified through morphological and molecular phylogenetic analyses based on the ITS marker. Its domestication potential was evaluated using various easy-access substrates. Total phenolic content and the antiradical activity against DPPH• were measured, and proximate content was assessed in cultivated basidiomata. [Results] The mixture of eucalyptus sawdust and straw yielded the highest production over a 45-day period, while the ethyl acetate fraction exhibited the highest concentration of phenolic compounds (35.6 ± 2.6 mg GAE g-1) and antiradical activity against DPPH• (13.6 ± 1.3 mg AAE g-1). In terms of proximate composition, F. rugulosus basidioma contains 20% protein, 15.4% carbohydrates, 25.2% dietary fiber, and 5.7% fat. [Conclusions] Regarding the cultivation of Favolus rugulosus, the eucalyptus sawdust-straw mixture presented the highest yields, biological efficiency, and number of flushes. Nutritional and chemical composition analyses of basidiomata revealed that F. rugulosus is an edible mushroom with potential use in the food industry as it is a rich source of protein, carbohydrates, dietary fiber, and essential fatty acids.

Pesticide misuse by farmers poses hazards to human, animal, and environmental health. [Objective] This study aimed to document potential pesticide formulation misuse in agricultural farms. [Methodology] Inadequate storage practices, incorrect pesticide selection, and pesticide formulation overuse were documented through interviews and photographs on 13 agricultural farms from the Cartago and Guanacaste provinces of Costa Rica between August 2022 and April 2023. [Results] Storage room characteristics in many farms do not comply with safety standards prescribed by the Costa Rican Ministry of Agriculture and Livestock. Different active ingredients with herbicidal, fungicidal, insecticidal, and bactericidal properties are used in crop species for which they are not recommended. These substances include those from the carbamate, pyridine, cyclohexanedione, pyrethroid, conazole, benzothiazinone, oxadiazine, and phthalimide chemical groups in Cartago province, and from the neonicotinoid and pyrethroid chemical groups in Guanacaste province. Many pesticide formulations are utilized in quantities exceeding the manufacturers' recommendations. Among these formulations were bifenthrin, captan, oxamyl, cypermethrin, mancozeb, dimethoate, and deltamethrin in Cartago province, and imidacloprid in Guanacaste province. [Conclusions] These substances and their secondary metabolites have the potential to move across different environmental compartments such as water, soil, and air, thereby negatively affecting the health of community members rather than just the farmers applying these formulations. Well-established pesticide education programs based on on-site visits to farmers can enhance awareness about implementing good practices and ensure rational use of these substances, with positive results in non-target organisms such as humans and ecosystem service providers as well as natural and anthropogenic ecosystems.

[Objective] This work aims to adapt and validate a scale that measures the level of self-regulation in mathematical problem-solving contexts of teachers in initial training in primary education. [Methodology] For sample selection, non-probabilistic convenience or incidental sampling was used. A total of 269 first-year primary education undergraduate degree students at the University of the Basque Country (UPV/EHU) in the 2020–2021 academic year participated in the validation process of the adapted scale. The type of research conducted is descriptive. Data were analyzed using the SPSS statistical software. [Results] The Cronbach's alpha coefficient value of 0.884 revealed a consistent internal reliability. Likewise, to test the factor structure of the scale, an exploratory factor analysis was conducted, obtaining a Kaiser-Meyer-Olkin (KMO) index of 0.836 > 0.7 and a p= 0.000<0.05 in the Bartlett test of sphericity. It also indicated a seven-factor structure: students' perceptions of their ability and how these perceptions influence self-regulation of the resolution process; ethics, problem-solving and personal growth; attitude towards the statement; negative self-efficacy beliefs; external causal attribution; problem-solving methods; and the social environment. [Conclusions] The latent structure provided by the exploratory factor analysis agrees with the classification of items established a priori and allows for the orientation of the confirmatory factor analysis that provides continuity to the research.

[Objective] This research project analyze math anxiety and anxiety experienced when teaching math by primary school teachers working for the Ministry of Public Education in Costa Rica. For this purpose, math anxiety and its three dimensions and math teaching anxiety and its four dimensions were determined. In addition, the influence of some variables such as academic performance, sex, and work experience on anxiety were also analyzed. [Methodology] The study was quantitative and had a sample of 372 practicing teachers (336 women and 36 men) from six regions of Costa Rica: San Carlos, North-North Zone, Limón, Los Santos, Puriscal, and Alajuela with ages between 23 and 63 years. Their experience as primary school teachers range from one year to 35 years, while 55 of them are still studying and 317 are not pursuing university studies. [Results] Higher academic performance is associated with lower MA and MTA scores. Furthermore, teachers suffer MA (Math Anxiety) and MTA (Math Teaching Anxiety), years of experience do not improve this situation, and less self-confident subjects experience more MTA. In addition, a positive correlation was found between MA, MTA, and their dimensions, being the correlations between GA (General Anxiety)-EA (Exam Anxiety), MA-GA, SC (Self-Confidence)-AMT (Attitude towards Math Teaching), and MTA-CK (Content Knowledge) the strongest. [Conclusions] The study concludes that the sample shows a significant percentage of MA and MTA, as well as their dimensions, which negatively affects attitude towards mathematics and teachers’ perception and self-confidence when teaching this subject.

[Objective] The aim is to explore how in-service teachers professionally view curricular materials and students' mathematical thinking in the area of measurement. [Methodology] The participants were 18 in-service primary school teachers, who completed a 12-item questionnaire with three focuses: (i) interpret students' mathematical thinking, (ii) propose activities to support students' understanding, and (iii) analyze activities related to curriculum references regarding magnitudes and their measurements. The analysis was conducted in two stages. In the first stage, the characteristics of the responses by in-service teachers to each of the items were identified, and in the second stage those characteristics were grouped according to the three focuses in order to identify any peculiarities on how teachers interpreted students' mathematical thinking and proposed and analyzed activities using the curriculum. [Results] Results indicate that teachers have difficulties in identifying errors because they do not consider the real context of the problem. Furthermore, although they were able to propose different activities, they had difficulties when asked to place the activity into an everyday context. The curricular difference between mathematical process and ability proved to be difficult for teachers in the area of measurement. [Conclusions] Teachers’ limitations show the need to develop continuing education proposals for in-service primary teachers that foster the development of teaching competences.

Aldehydes are compounds in the atmosphere formed by the photochemical degradation of other organic compounds in the troposphere and can be emitted by natural or anthropogenic sources. [Objective] An analytical method was implemented to quantify aldehyde samples in matrices such as air and rainwater. [Methodology] Aldehyde sampling and analysis were conducted using method TO-11 from the United States Environmental Protection Agency (EPA). Sampling was carried out by using adsorption cartridges coated with a 2,4-DNPH solution, forming a hydrazone with the aldehydes present in the rainwater and the air, which were tested using a liquid chromatograph coupled to a UV-visible detector (HPLC-UV/Vis). To validate the analysis technique and the analytical quality of the results, the following was determined: linearity, sensitivity, quantification limits, detection limits, repeatability, reproducibility, and recovery percentage. In the case of repeatability, the comparison of the Horwitz coefficient of variation was used with the percentages of relative standard deviation (% RSD) of the samples. [Results] The detection and quantification limits obtained range between 0.18 μg/m3 and 3.20 μg/m3 for acetaldehyde and acrolein, respectively, while quantification limits are between 0.62 μg/m3 for acetaldehyde and 4.70 μg/m3 for heptanal, data that characterizes the method’s analytical quality. [Conclusions] In general, the analysis method for aldehydes showed linearity, with R2 values equal to or greater than 0.9991 for each calibration curve, and relative deviation percentage values less than 2.25 %, indicating good precision in the analysis.