Fruits of Schinus terebinthifolia Raddi were investigated. A fast and efficient method for the simultaneous determination of 11 polyphenolic substances by high performance liquid chromatography-diode array detector (HPLC-DAD) was applied. Limits of quantification ranged between 0.78 and 3.14 mg L-1. High concentrations of kaempferol were found. An exploratory evaluation was performed using principal component analysis (PCA) for fruit origin differentiation. Total phenolic content (TPC) ranged from 274 to 517 mg GAE 100 g-1; total flavonoid content (TFC) ranged from 101 to 283 mg QE 100 g-1. In vitro analyses showed that antioxidant capacity with 2,2-diphenyl-1-picrylhydrazyl (DPPH) ranged from 1.7 to 7 µM DPPH 100 g-1. The bacteriostatic and bactericidal effect were also evaluated against: Bacillus subtilis, B. cereus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella choleraesuis, Candida albicans and C. glabrata, using broth microdilution assay. It can be inferred that S. terebinthifolia Raddi fruit has the potential to act as an ally in the search for new alternatives in the action against pathogens, and it can be used as a potential natural antioxidant and antimicrobial agent. Metals (Cu, Fe, Mg, Mn and Zn) were also determined by flame atomic absorption spectrometry (FAAS), with emphasis on high concentrations of Mg, Zn and Fe. investigated 1 chromatographydiode chromatography diode HPLCDAD HPLC DAD (HPLC-DAD applied 078 0 78 0.7 314 3 14 3.1 L1. L1 L 1. L-1 found PCA (PCA differentiation TPC (TPC 27 51 10 g1 g g-1 TFC (TFC 28 g1. 2,2diphenyl1picrylhydrazyl 22diphenyl1picrylhydrazyl diphenylpicrylhydrazyl 2,2 diphenyl picrylhydrazyl 2 (DPPH 17 subtilis B cereus aureus coli aeruginosa choleraesuis C glabrata assay S pathogens agent Cu, Cu (Cu Fe Mg FAAS, FAAS , (FAAS) 07 0. 31 3. L- 5 g- 2diphenyl1picrylhydrazyl 22 2, (FAAS

Palicourea tomentosa (Aubl.) Borhidi (Rubiaceae, Palicoureeae), earlier classified as Psychotria poeppigiana Müll. Arg., is used in folk medicine for a variety of diseases. Biological studies on the plant describes their vasorelaxant, antiplasmodial, antitumoural and anticholinesterase activities. To expand the knowledge on the chemical and biological potential of this species, in this work, phytochemical and dereplication studies, as well as antimicrobial and anticholinesterase evaluation of Palicourea tomentosa were carried out. Phytochemical investigation deals with the isolation of lutein (1), a mixture of dehydrovomifoliol (2) and megastigma-4,7-dien-3-one (3), loliolide (4), 5,13-epoxy-9-hydroxy-megastigma-7-en,3-one (5), vomifoliol (6), asperuloside (7), 3-O-p-coumaroylquinic acid (8), and a mixture of the pyrrolizidinoindoline alkaloids hodgkinsine (9), chimonanthine (10) and psychotriasine (11). The ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC HRMS/MS) based on molecular networking dereplication of dichloromethane fraction led to putative identification of other two megastigmanes, one terpene lactone and three carotenoids, besides seven triterpenes and four indole alkaloids. The dichloromethane, ethyl acetate and hydromethanol fractions of P. tomentosa were able to inhibit Candida albicans with minimum inhibitory concentrations (MICs) of 125, 250 and 125 µg mL-1, respectively. The methanol crude extract, dichloromethane and alkaloid fractions inhibited selectively the butyrilcholinesterase (BuChE) at percentages of 63.09, 60.39 and 56.22%, respectively. Aubl. Aubl (Aubl. Rubiaceae, Rubiaceae (Rubiaceae Palicoureeae, Palicoureeae , Palicoureeae) Müll Arg Arg. diseases vasorelaxant antiplasmodial activities species work out 1, 1 (1) 2 (2 megastigma4,7dien3one megastigma47dien3one megastigmadienone megastigma 4,7 dien 3 4 7 3, (3) 4, (4) 5,13epoxy9hydroxymegastigma7en,3one 513epoxy9hydroxymegastigma7en3one epoxyhydroxymegastigmaenone 5,13 epoxy 9 hydroxy en,3 5 13 en 5, (5) 6, 6 (6) 7, (7) 3Opcoumaroylquinic Opcoumaroylquinic O p coumaroylquinic 8, 8 (8) 9, (9) 10 (10 11. 11 . (11) ultrahigh ultra high highresolution resolution UHPLC HRMS/MS HRMSMS HRMS MS megastigmanes carotenoids P MICs (MICs 25 12 mL1, mL1 mL mL-1 respectively extract BuChE (BuChE 6309 63 09 63.09 6039 60 39 60.3 5622 56 22 56.22% (Aubl (1 ( megastigma4 7dien3one 47 (3 (4 13epoxy9hydroxymegastigma7en 3one hydroxymegastigma 513 5,1 en3 en, (5 (6 (7 (8 (9 (11 mL- 630 0 63.0 603 60. 562 56.22 dienone epoxyhydroxymegastigmaen 51 63. 56.2 56.

ABSTRACT The correct use of tyres on agricultural tractors, in respect of the terrain and the type and internal pressure of the tyre, are factors that influence the performance of the tractor. The aim of the present study was to evaluate the operating performance of an agricultural tractor fitted with two types of traction device (radial and diagonal tyres) at different pressures, and operating on soil with two levels of moisture. The experiment was conducted on a dystrophic Red Yellow Argisol, with tests to evaluate the performance of the tyres under specific working conditions. Tractive power and tractive force, wheel slip and fuel consumption were evaluated. For each of the conditions under evaluation, the radial configuration showed better performance than the diagonal configuration, the effect being more significant at the lower pressure and under low soil moisture. The use of radial tyres led to an increase in traction capacity and drawbar power, with a reduction in fuel consumption, especially at higher slip rates. tractors tyre pressures moisture Argisol force evaluated evaluation rates

Abstract The technique of bending wood by vaporization presents itself as a viable option for curvilinear structural projects, such as gridshells. Coniferous woods are often used in roof structures because, in addition to the desired relationship between mechanical strength and density, they allow the complete treatment of the cross-section of the piece. However, characteristics such as the predominance of sapwood or heartwood and the presence of defects are variables that affect structural performance. The aim of this study was to evaluate the bending limit of Acrocarpus laxinifloius (Indian cedar) veneers with a bending radius of 21 cm at different thicknesses. The impact of the predominance of sapwood or heartwood and the presence of defects on the bending strength was also investigated. The literature indicates that plastic flexibilization by steam occurs at 100°C, with 2.4 minutes for each millimeter of lamella thickness, which were the parameters considered in this study. The statistical analysis indicated a thickness limit of 8 mm for the lamellae to bend and the greater presence of sapwood or heartwood, as well as wood defects, did not significantly affect the bending force. projects gridshells because density crosssection cross section piece However performance Indian cedar 2 thicknesses investigated 100C C 100 100°C 24 4 2. force 10 1

Resumo Atécnica de vergamento da madeira por vaporização se apresenta como opção viável para projetos de estruturas curvilíneas, como as gridshells. Madeiras coníferas são comumente adotadas em estruturas de cobertura, pois além da desejada relação entre resistência mecânica e densidade, permitem o completo tratamento da seção transversal da peça. Entretanto, características como a predominância de alburno ou de cerne e a presença de defeitos são variáveis que afetam o desempenho estrutural. O objetivo deste estudo foi avaliar o limite de vergamento de lamelas de Acrocarpus flaxinifloius (cedro indiano) com raio de curvatura de 21 cm em diferentes espessuras. Também se investigou o impacto da predominância de alburno ou cerne e da presença de defeitos na força de vergamento. A literatura indica que a flexibilização plástica por vapor ocorre a 100°C, com 2,4 minutos para cada milímetro de espessura da lamela, parâmetros estes considerados neste estudo. A análise estatística indicou o limite de 8 mm de espessura para o vergamento das lamelas e a maior presença de alburno ou de cerne, bem como os defeitos da madeira, não afetou significativamente a força de vergamento. curvilíneas gridshells cobertura densidade peça Entretanto estrutural cedro indiano 2 espessuras 100C C 100 100°C 24 4 2, lamela 10 1

Abstract This study handles the possibility of formulating artisanal paints for wall paintings whose pigments come from plants, considering the need for additives and techniques capable of guaranteeing a good performance for internal walls of buildings. The lack of recipes and publications on the proportion of each component to obtain a paint with good performance motivated the preparation of the present research, in which formulations were developed through experimental design of mixtures to obtain homogeneous suspensions that comply with the limits stipulated by NBR 15079-1:2021. The performance of the mixtures in the Abrasion Resistance Test was evaluated according to the variations in the proportions of the components of the mixtures, and the pH and viscosity variable. The results indicate that the highest levels of abrasion resistance were achieved by raising the levels of pigment and bactericide, while high pH indices showed high viscosity and good performance against abrasion resistance, and vice versa. Through this study, it is concluded that it is possible to elaborate paints with Curcuma Longa L. pigments and natural inputs with satisfactory performance for the application and elaboration of mural paintings on internal walls of buildings. plants buildings research 1507912021. 1507912021 15079 1 2021. 2021 15079-1:2021 variable bactericide versa L 150791202 1507 202 15079-1:202 15079120 150 20 15079-1:20 1507912 15 2 15079-1:2 150791 15079-1: 15079-1 15079-

Resumo Opresente estudo buscou formular tintas artesanais para pinturas de murais cujos pigmentos sejam oriundos de plantas, considerando a necessidade de aditivos e técnicas capazes de garantir um bom desempenho para paredes internas de edificações. A falta de receitas e publicações sobre a proporção de cada componente para a obtenção de uma tinta com bom desempenho motivou a elaboração da presente pesquisa, em que foram desenvolvidas formulações através de delineamento experimental de misturas para obter suspensões homogêneas que estejam em conformidade com os limites de desempenho definidos pela NBR 15079-1:2021. O desempenho das misturas frente ao ensaio de resistência à abrasão (RAU) foi avaliado de acordo com as variações das proporções dos componentes das misturas e as variáveis de pH e viscosidade. Os resultados indicam que os índices mais elevados de RAU foram alcançados ao elevar os níveis de pigmento e bactericida, ao passo que altos índices de pH apresentaram viscosidade elevada e bom desempenho frente à RAU, e vice-versa. Através do presente estudo, conclui-se que é possível elaborar tintas com pigmentos de Curcuma Longa L. e insumos naturais com desempenho satisfatório para aplicação e elaboração de pinturas murais em paredes internas de edificações. plantas edificações pesquisa 1507912021. 1507912021 15079 1 2021. 2021 15079-1:2021 (RAU bactericida viceversa. viceversa vice versa. versa vice-versa concluise conclui se L 150791202 1507 202 15079-1:202 15079120 150 20 15079-1:20 1507912 15 2 15079-1:2 150791 15079-1: 15079-1 15079-

Abstract The improvement intention that precedes the improvement behavior of employees is a primary factor for companies that employ them to achieve their objectives. In this study, the influence of two Performance Appraisal (PA) variables was examined: supervisor diligence and subordinates' reactions to the PA meeting. Thirteen control variables were incorporated into the analysis, including 7 demographic and 6 factors related to performance evaluation, such as individualized consideration, relationship, supervisor support, procedural justice, accuracy of PA, and satisfaction with PA. Data were collected through a questionnaire provided by McClendon et al. and responses were obtained from 224 employees of automotive manufacturing companies in the city of Aguascalientes. The reliability coefficients of the questionnaire were high, indicating robust consistency in the responses. A multiple regression analysis revealed an explanatory model of 0.456 of the variance in improvement intention, highlighting the significant contribution of the supervisor's feedback and diligence factors, without the inclusion of control variables. In this context, feedback stood out as the key factor, suggesting that allocating organizational resources for supervisor training could generate greater benefits in employee improvement behavior. These findings highlight the importance of supervisor feedback and diligence as critical elements in driving improvement intention among employees.

Resumen La intención de mejora que precede al comportamiento de mejora de los empleados es un factor primordial para que las empresas que los emplean logren sus objetivos. Este estudio examinó la influencia de dos variables de la Evaluación del Desempeño (ED): la diligencia del supervisor y las reacciones de los subordinados a la reunión de ED. Se incorporaron al análisis 13 variables de control, que incluyeron 7 demográficas y 6 factores relacionados con la evaluación del desempeño, tales como consideración individualizada, relación, apoyo del supervisor, justicia procedimental, precisión de la ED y satisfacción con la ED. Los datos se recopilaron a través de un cuestionario proporcionado por McClendon et al. y se obtuvieron respuestas de 224 empleados de empresas manufactureras automotrices de la ciudad de Aguascalientes. Los coeficientes de confiabilidad del cuestionario fueron altos, indicando una consistencia robusta en las respuestas. Un análisis de regresión múltiple reveló un modelo explicativo del 0.456 de la varianza en la intención de mejora, destacando la contribución significativa de los factores de retroalimentación y diligencia del supervisor, sin la inclusión de las variables de control. En este contexto, la retroalimentación se destacó como el factor clave, sugiriendo que la asignación de recursos organizacionales para la capacitación de supervisores podría generar mayores beneficios en el comportamiento de mejora de los empleados. Estos hallazgos resaltan la importancia de la retroalimentación y la diligencia del supervisor como elementos críticos en el impulso de la intención de mejora entre los empleados.

Resumen Introducción. Las medidas de adaptación al cambio climático requieren de la toma de decisiones informadas. Sin embargo, la agricultura de pequeña escala muestra bajas tasas de adopción de tecnologías por su costo y falta de conectividad. Objetivo. Evaluar tres prototipos de dispositivos para agricultura de pequeña escala y de bajo costo para medir humedad de suelo en diferentes texturas, así como determinar las respectivas ecuaciones de calibración y los efectos de conductividad eléctrica y temperatura en la medida de humedad. Materiales y métodos. Se evaluaron tres prototipos de dispositivos de medición y registro de humedad de suelo, en suelos con diferencial en contenido de arcilla/arena y conductividad eléctrica en parcelas productivas de la Universidad Zamorano, en Honduras; y Finca demostrativa en Popayán, Colombia, durante el primer trimestre del 2022. Se tomaron como referencia sensores comerciales para la comparación del desempeño de los prototipos, mediante análisis de regresión de las lecturas por hora de los sensores durante 90 días. Se recolectaron las variables de conductividad eléctrica (dS/m) y temperatura para determinar la influencia en la precisión de la lectura de humedad. Resultados. Los dispositivos de medición y registro de humedad presentaron un mejor desempeño en suelos con menor contenido de arena. La medición de los dispositivos sobrestimó entre 0,19 y 0,52 puntos porcentuales la lectura de humedad por cada grado adicional de temperatura del suelo, y que por cada dS/m adicional de conductividad eléctrica la lectura se debe ajustar entre 8 y 55 puntos porcentuales. Conclusiones. El prototipo A fue el dispositivo más exacto, mientras que el prototipo B fue el más preciso, con respecto a los sensores comerciales. Los dispositivos de humedad presentaron un mejor desempeño en suelos con menor contenido de arena. Los tres modelos evaluados obtuvieron el mejor desempeño en suelo franco con contenido medio de arcilla.

Abstract Introduction. Climate change adaptation measures require informed decision-making. However, small-scale agriculture shows low rates of technology adoption due to cost and lack of connectivity. Objective. To evaluate three low-cost prototypes of small-scale agriculture devices for soil moisture measurement in different soil textures, as well as to determine the respective calibration equations, and the effects of electrical conductivity and temperature on moisture measurement. Materials and methods. Three measurement and recording prototypes for soil moisture were evaluated in soils with variations in clay/sand content and electrical conductivity in productive plots at Zamorano University in Honduras and a demonstration farm in Popayán, Colombia during the first quarter of 2022. Commercial sensors were used as a reference to compare the performance of the prototypes through regression analysis of hourly sensor readings over 90 days. Electrical conductivity (dS/m) and temperature variables were collected to determine their influence on moisture reading accuracy. Results. The soil moisture measurement devices showed better performance in soils with lower sand content. The measurement from the devices overestimated moisture readings by 0.19 to 0.52 percentage points for each additional degree of soil temperature. Additionally, for each additional dS/m of electrical conductivity, the reading needed adjustment by 8 to 55 percentage points. Conclusions. Prototype A was the most accurate device, while prototype B was the most precise compared to commercial sensors. Soil moisture devices performed best in soils with lower sand content. The three models evaluated performed best in loam soil with a medium clay content.

Summary: Excessive use of chlorpyrifos affects the quality of agricultural soils causing negative effects on the safety of harvested food. The behavior of chlorpyrifos residues depends on soil properties, especially organic matter. Our aim in this research was to determine the effect of the application of vermicompost on the residual and dissipation of chlorpyrifos in an entisol soil of semi-arid climate with variations in its edaphic fertility. Four treatments were studied. T1: 7.5% vermicompost (V) and 92.5% soil (S); T2: 5% V and 95% S; T3: 2.5% V and 97.5% S; T4: 0% V and 100% S. The treatments were subjected to a seven-day incubation period. Subsequently, a dose of chlorpyrifos of 1.5 mg kg-1 as active ingredient was applied once for each treatment. A completely randomized design was used with three replicates for each treatment, forming 12 experimental units. The analytical determination of chlorpyrifos was carried out by high performance liquid chromatography (HPLC). The evaluations were carried out 1.7, 14, 28, 42, 70 and 98 days after the application of chlorpyrifos. The results showed that the incorporation of vermicompost to the soil at increasing levels promoted a decrease in the residual concentration of chlorpyrifos and facilitated its gradual dissipation. The chlorpyrifos dissipation curves correspond to a first order logarithmic equation where the effects of the treatments caused greater dissipation of chlorpyrifos as the evaluation period elapsed. At 98 days of evaluation, T1 registered lower residuality (0.786 m kg-1), higher daily dissipation rate (0.008) and lower half-life of chlorpyrifos (86.64 days). At the end of the research period, edaphic levels of P, K, EC and CEC increased while OM, N and pH decreased after vermicompost application.

Resumen: El uso excesivo de clorpirifos afecta la calidad de los suelos agrícolas provocando efectos negativos en la inocuidad de los alimentos cosechados. El comportamiento de los residuos de clorpirifos depende de las propiedades edáficas especialmente la materia orgánica. El objetivo de la investigación fue determinar el efecto de la aplicación de vermicompost en la residualidad y disipación de clorpirifos en un suelo entisol de clima semiárido con variaciones en su fertilidad edáfica. Se estudiaron cuatro tratamientos. T1: 7.5% vermicompost (V) y 92.5% suelo (S); T2: 5% V y 95% S; T3: 2.5% V y 97.5% S; T4: 0% V y 100% S. Los tratamientos fueron sometidos a un periodo de incubación de siete días. Posteriormente, se aplicó una dosis de clorpirifos de 1.5 mg kg-1 como ingrediente activo en una sola oportunidad por cada tratamiento. Se utilizó un diseño completamente al azar con tres repeticiones por cada tratamiento conformando 12 unidades experimentales. La determinación analítica de clorpirifos se efectuó por cromatografía líquida de alta resolución (HPLC). Las evaluaciones se realizaron a 1,7, 14, 28, 42, 70 y 98 días de la aplicación de clorpirifos. Los resultados demostraron que la incorporación de vermicompost al suelo en niveles crecientes promovió la disminución de la concentración residual de clorpirifos y facilitó su disipación de manera gradual. Las curvas de disipación de clorpirifos corresponden a una ecuación logarítmica de primer orden donde los efectos de los tratamientos ocasionaron mayor disipación de clorpirifos conforme transcurrió el periodo de evaluación. A 98 días de evaluación el T1 registró menor residualidad (0.786 m kg-1), mayor tasa de disipación diaria (0.008) y menor vida media de clorpirifos (86.64 días). Al final del periodo de investigación, los niveles edáficos de P, K, CE y CIC se incrementaron mientras que la MO, N y pH descendieron luego de la aplicación de vermicompost.

Summary: Bioestimulants such as chitosan in traditional agriculture have proven effective in promoting plant growth and development, as well as protecting them from diseases. However, in aquaponic production systems its effect is not documented, therefore the objective of the present work was to determine the effect of chitosan concentration (0, 500 and 1000 mg L-1) in three varieties (Great Lakes, Regina 500 and Red Rock) of lettuce (Latuca sativa L.), on production parameters in a circular aquaponics system. Using a completely randomized design with a 3×3 factorial arrangement, chitosan was applied by spraying at 10 and 45 days after transplantation. After the analysis of variance, the differences due to the variety were determined using the Tukey test and the effect of chitosan concentration through orthogonal polynomials, in addition to a correlation analysis and simple linear regression between the yield, height, number and length of the leaves. The results showed that the variables number of leaves, length of leaves and root, plant weight, plant height and yield increased as the dose of chitosan increased. The Red Rock variety outperformed the Regina 500 and Great Lakes varieties. No presence of insects or diseases was detected. It is concluded that chitosan favors the growth, development and yield of the lettuce plant in a circular aquaponic system, especially with doses of 1000 mg L-1 of chitosan, and that with respect to these same variables, the Red Rock variety surpasses to the Regina 500 and Great Lakes varieties.

Resumen: Los bioestimulantes como el quitosano en la agricultura tradicional han demostrado su eficacia para promover el crecimiento y desarrollo de las plantas, así como protegerlas de enfermedades. Sin embargo, en sistemas de producción acuapónicos su efecto no está documentado, por ello el objetivo del presente trabajo fue determinar el efecto de la concentración de quitosano (0, 500 y 1000 mg L-1) en tres variedades (Grandes Lagos, Regina 500 y Red Rock) de lechuga (Latuca sativa L.), sobre los parámetros de producción en un sistema circular de acuaponía. Utilizando un diseño completamente al azar con un arreglo factorial 3×3 el quitosano se aplicó mediante aspersión a los 10 y 45 días después del trasplante. Posterior al análisis de varianza, las diferencias debido a la variedad se determinaron utilizando la prueba de Tukey y, el efecto de la concentración de quitosano mediante polinomios ortogonales, además de un análisis de correlación y regresión lineal simple entre el rendimiento, altura, número y longitud de las hojas. Los resultados demostraron que las variables número de hojas, longitud de hojas y raíz, peso de planta, altura de planta y rendimiento, se incrementó conforme se aumentó la dosis de quitosano. La variedad Red Rock superó a las variedades Regina 500 y Grandes Lagos. No se detectó la presencia de insectos ni enfermedades. Se concluye que el quitosano favorece el crecimiento, desarrollo y rendimiento de la planta de lechuga en un sistema circular de acuaponía, sobre todo con dosis de 1000 mg L-1 de quitosano, y que respecto a estas mismas variables, la variedad Red Rock supera a las variedades Regina 500 y Grandes Lagos.

Abstract It is known that neuronal maturation after birth lasts approximately twenty years and requires a large amount of energy. If a pregnancy occurs before maturation, the energy must be distributed between the mother and the offspring, having an effect on the anatomical and functional processes of the brain. Therefore, the electrical activity of the frontal cortex was compared, as well as the performance of its functions and maternal care in adolescents and young people (less than six months after giving birth). The NEUROPSI test (attention and coding) and a maternal care instrument were applied to primiparous adolescents and young people; electroencephalographic recordings were performed on a sample of this population. Significant differences are observed in the coding and attention processes (F= 4.5, α= 0.03*; F= 79.7, α= 0.00**), and a significant correlation between attention and maternal care (health and affection categories) as well as health care coding. The electrical activity of the frontal lobe was slower in primiparous adolescents as well as maternal care behaviors. The above is related to delay in the neuronal maturation of adolescent mothers.

Resumen Se sabe que la maduración neuronal tras el nacimiento dura aproximadamente veinte años y necesita gran cantidad de energía. Si ocurre un embarazo antes de la maduración, la energía debe repartirse entre la madre y la cría, teniendo efecto en los procesos anatómicos y funcionales del cerebro. Por ello, se comparó la actividad eléctrica de la corteza frontal, así como el desempeño de sus funciones y cuidados maternales en adolescentes y jóvenes (con menos de seis meses posteriores al parto). Se aplicó el test NEUROPSI (atención y codificación) y un instrumento de cuidados maternales a primíparas adolescentes y jóvenes; a una muestra de esta población se les realizó registros electroencefalográficos. Se observan diferencias significativas en los procesos de codificación y atención (F= 4.5, α= 0.03*; F=79.7, α= 0.00**), y una correlación significativa entre la atención y el cuidado maternal (categorías de salud y cariño), así como de la codificación sobre el cuidado de la salud. La actividad eléctrica del lóbulo frontal fue más lenta en las adolescentes primíparas, así como las conductas de cuidado maternal. Lo anterior se relaciona con una menor maduración neuronal de madres adolescentes.

Resumen: La investigación determinó el efecto de la mediación de un videojuego educativo en el fortalecimiento de la resolución de problemas de matemáticas. El método cuantitativo con alcance descriptivo fue aplicado. La muestra fue no probabilística con 20 estudiantes de la Institución Educativa San Jorge, en la vereda Las Damas, Municipio de Purificación, Departamento de Tolima. Las variables estudiadas fueron: desempeño en resolución de problemas, mecánicas y percepción del videojuego. La encuesta inicial reflejó que un 90% no poseían habilidades matemáticas básicas y tenían una percepción negativa del área. Entonces, fue diseñada una estrategia educativa con un videojuego denominado Corredor Matemático de Pensamiento Variacional (Comapeva), en tercera persona con Unity 3D, Adobe Ilustrator y Autodesk 3d. Fue protagonizado por Comaco: joven aventurero que superó retos matemáticos. El guion narrativo combinó elementos del constructivismo, Aprendizaje Basado en Retos (ABR) y modelo instruccional ADDIE (Análisis, Diseño, Desarrollo, Implementación y Evaluación). La herramienta fue implementada con el apoyo de los docentes. Con el videojuego el 100% de los estudiantes resolvieron retos con diversas estrategias. Disminuyó un 21% el tiempo de desarrollo de los problemas, y un 33% las solicitudes de apoyo del docente. La concentración, atención, memoria, agilidad mental, interpretación y análisis fueron fortalecidas. El videojuego facilitó la construcción de conocimientos en matemáticas de forma sustancial. En consecuencia, fue innovador, motivador y permitió la trasformación de prácticas educativas según las necesidades de aprendizaje.

Abstract: The research considers the effect of the mediation of an educational video game in strengthening mathematics problem solving. The quantitative method with a descriptive scope was applied. The sample was non-probabilistic with 20 students from the San Jorge Educational Institution, in Las Damas village, Municipality of Purificación, Department of Tolima. The variables studied were problem-solving performance, game mechanics, and videogame perception. The initial survey showed that 90% of the students did not have basic mathematical skills and had a negative perception of the subject area. Therefore, an educational strategy was then designed using a video game called the Variational Thinking Mathematical Corridor (Comapeva). The game was developed in third person using Unity 3D, Adobe Illustrator, and Autodesk 3d. It starred Comaco: a young adventurer who overcame mathematical challenges. The narrative script combined elements of constructivism, Challenge-Based Learning (CBL) and instructional model ADDIE (Analysis, Design, Development, Implementation and Evaluation). The tool was implemented with the support of the teachers. With the video game, 100% of the students were able to solve challenges using various strategies. Problem development time decreased by 21%, and teacher support requests decreased by 33%. Concentration, attention, memory, mental agility, interpretation, and analysis skills were all strengthened. The video game facilitated the construction of knowledge in mathematics in a substantial way. Consequently, the video game was found to be innovative and motivating, and it allowed for the transformation of educational practices according to the students' learning needs.

Resumen (Objetivo) Aunque el uso de vídeos de aula no es un tópico novedoso en la formación inicial del profesorado de educación matemática infantil, todavía hay preguntas de investigación sin resolver asociadas, sobre todo, a criterios para seleccionar y analizar vídeos desde un enfoque didáctico y disciplinar. Desde esta perspectiva, la finalidad del artículo es diseñar y validar una rúbrica que sirva para este doble propósito. (Metodología) A partir de un paradigma de investigación cualitativo, se ha seguido un proceso 4x3, es decir, un método secuenciado en cuatro fases con tres pasos en cada una de ellas: 1) revisión, 2) creación, 3) contraste y evaluación, y 4) mejora. (Resultados) La versión definitiva de la rúbrica, denominada R4, consta de 28 ítems organizados en cuatro dimensiones: 1) rol docente, sobre la función que tiene cada docente en el aula; 2) respuesta del alumnado infantil en la tarea, sobre su actuación; 3) relaciones matemáticas, sobre el tipo de matemática; 4) recursos, sobre la gestión y uso de recursos-materiales humanos. Para cada dimensión se considera diversas subdimensiones, en total 16. (Conclusiones) Se concluye que la rúbrica R4 aborda aspectos fundamentales (rol docente, respuesta del alumnado infantil, relaciones matemáticas y recursos) en la labor docente de una maestra o maestro de educación infantil, lo cual permite analizar la práctica docente de un modo holístico y fundamentado.

Resumo (Objetivo) Embora o uso de vídeos em sala de aula não seja um tópico novo na formação inicial de professores de matemática da educação infantil, ainda há questões de pesquisa não resolvidas associadas, sobretudo, aos critérios de seleção e análise de vídeos a partir de uma abordagem didática e disciplinar. A partir dessa perspectiva, o objetivo do artigo é projetar e validar uma rubrica que atenda a essa dupla finalidade. (Metodologia) Com base em um paradigma de pesquisa qualitativa, foi seguido um processo 4x3, ou seja, um método sequenciado em quatro fases com três etapas em cada uma delas: 1) revisão, 2) criação, 3) contraste e avaliação, e 4) aprimoramento. (Resultados) A versão final da rubrica, denominada R4, consiste em 28 itens organizados em quatro dimensões: 1) papel do professor, sobre a função que cada professor tem na sala de aula; 2) resposta dos alunos à tarefa, sobre seu desempenho; 3) relações matemáticas, sobre o tipo de matemática; 4) recursos, sobre o gerenciamento e o uso de recursos humanosmateriais. Para cada dimensão são consideradas diversas subdimensões, totalizando 16. (Conclusões) Conclui-se que a rubrica R4 aborda os principais aspectos (função do professor, resposta dos alunos da educação infantil, recursos e relações matemáticas) no trabalho de ensino de um professor da educação infantil, o que permite uma análise holística e informada da prática de ensino.

Abstract (Objective) Although the use of classroom videos is not a new topic in the initial training of early childhood mathematics education teachers, there are still unresolved research questions associated, above all, with criteria for selecting and analyzing these videos from both a didactic and disciplinary approach. From this perspective, the purpose of this article is to design and validate a rubric that serves this dual purpose. (Methodology) Based on a qualitative research paradigm, a 4x3 process has been followed, that is, a method sequenced in four phases with three steps in each one of them: 1) Review; 2) Creation; 3) Contrast and Evaluation; and 4) Improvement. (Results) The final version of the rubric, called R4, consists of 28 items organized in four dimensions: 1) Teaching role, on the role of the teacher in the classroom; 2) Response of children in the task to his/her performance; 3) Mathematical relations, on the type of mathematics; 4) and Resources, on the management and use of human resources and materials. For each dimension, several subdimensions are considered, 16 in total. (Conclusions) It is concluded that the R4 rubric addresses fundamental aspects (Teaching role, Childrens’ response, Mathematical relations and Resources) in the teaching work of an early childhood education teacher, which allows analyzing the teaching practice in a holistic and justified way.

The aim of this study is to identify the guiding principles of game activism to contribute to possible definitions of the movement, allowing similar phenomena to be identified and distinguished from other activisms. The territoriality of the research is built on the confrontation between the categories of games and their articulation with activism and the streets. Starting from the basic concept of game activism as the use of electronic games in the articulation of these languages with social and political objectives, the article will go through the movements in their different fronts of action, such as educational use, promoting social causes and criticizing the games industry. As part of ongoing research, it is based more on hypotheses than conclusions: the nature of the video game, when considering its genealogy - in this context, from commercial battles to maintaining the aesthetic ideal of graphic performance - is competitive and commercialized and a deconstructed video game demands more than inclusion policies. The deconstruction of the video game demands and participates in the dismantling of communities, commercial exchanges, labour and aesthetic concepts; the military past and the financial nature of the video game-product define a category of game, but do not limit the creative power of the video game. Crossing the debate on gamification or educational games, the question of the console, platforms and hacking in the colonizing principle of the game or narrative as power, game activism is developing in a complex context that requires careful evaluation to question the limits and possibilities of this emerging language of activism.

O presente trabalho tem como objetivo levantar os princípios norteadores do gameativismo para contribuir para possíveis definições do movimento, permitindo a identificação de fenômenos semelhantes e a distinção de outros ativismos. A territorialidade da pesquisa se constrói pelo confronto entre as categorias de games e as articulação destas com o ativismo e as ruas. Partindo do conceito base de gameativismo como o uso de jogos eletrônicos na articulação destas linguagens com objetivos sociais e políticos, o artigo atravessará os movimentos em suas diferentes frentes de ação, como o uso educativo, na promoção de causa sociais e para a crítica à indústria de jogos. Como parte de uma pesquisa em andamento, parte-se mais de hipóteses que de conclusões: a natureza do videogame, quando considerada sua genealogia - nesse contexto, das batalhas comerciais até a manutenção do ideal estético da performance gráfica - é competitiva e mercadológica e um videogame desconstruído exige mais que políticas de inclusão. A desconstrução do videogame demanda e participa da desestruturação das comunidades, das trocas comerciais, do trabalho e de conceitos estéticos; o passado militar e o caráter financeiro do videogame-produto definem uma categoria de jogo, mas não limitam sua potência criativa. Atravessando o debate da gamificação ou jogos educativos, a questão do console, das plataformas e do hacking no princípio colonizador do game ou da narrativa como poder, o gameativismo se desenvolve em um contexto complexo, que demanda avaliação criteriosa a fim de questionar os limites e as possibilidades dessa linguagem emergente de ativismo.

RESUMO Introdução: este artigo foi elaborado a partir da detecção de insuficiências teórico-metodológicas e práticas no processo de preparação técnica da natação artística escolar. Objetivo: desenvolver uma concepção teórica com ma nova forma de reestruturação do conteúdo para o treinamento de figuras, a partir da sua periodização, que favoreça o aumento do desempenho esportivo em nadadores artísticos da categoria escolar. Materiais e métodos: métodos analítico-sintéticos e sistêmicos estrutural-funcionais foram utilizados como métodos teóricos de pesquisa científica. Análise empírica, documental e parecer pericial. Como métodos matemático-estatísticos, estatística descritiva e inferencial, com Teste W de Kendall. Resultados: a qualidade da concepção teórica foi corroborada pela avaliação emitida pelos 15 especialistas selecionados, que tiveram relação direta quer com o treino desportivo, quer de forma articular com o treino da natação artística cubana. Conclusões: os especialistas na avaliação dos indicadores destacam a sua funcionalidade, relevância e viabilidade.

ABSTRACT Introduction: This article was carried out based on identifying theoretical, methodological, and practical shortcomings in the technical preparation process of school artistic swimming. Objective: To develop a theoretical concept with a new way of restructuring the content for the training of figures, based on theirs periodization, which favors the increase of sports performance in school-age artistic wimmers. Materials and Methods: The theoretical methods of scientific research used were analytical-synthetic and systemic-functional. Empirical methods included documentary analysis and expert criteria. Mathematical-statistical methods involved descriptive and inferential statistics, using the Kendall's W Test. Results: The quality of the theoretical concept was confirmed by the evaluation issued by the 15 selected experts, who had a direct relationship either with sports training or in a particular way in the training of Cuban artistic swimming. Conclusions: Experts evaluating the indicators emphasize their functionality, relevance, and feasibility.

RESUMEN Introducción: el presente artículo se realizó a partir de detectar insuficiencias teórico-metodológicas y prácticas en el proceso de preparación técnica de la natación artística escolar. Objetivo: elaborar una concepción teórica con una nueva forma de reestructurar el contenido para el entrenamiento de las figuras, sobre la base de su periodización, que favorezca el incremento del rendimiento deportivo en nadadores artísticos categoría escolar. Materiales y métodos: se emplearon como métodos teóricos de la investigación científica el analítico-sintético y el sistémico estructural funcional. De los empíricos, el análisis documental y el criterio de expertos. Como métodos matemático-estadísticos, la estadística descriptiva e inferencial, con la Prueba de W de Kendall. Resultados: la calidad de la concepción teórica quedó corroborada por la evaluación emitida por los 15 expertos seleccionados, que tuvieran relación directa ya sea con el entrenamiento deportivo o de modo particular en el entrenamiento de la natación artística cubana. Conclusiones: los expertos en la evaluación de los indicadores, resaltan su funcionabilidad, pertinencia y factibilidad.

ABSTRACT As a result of the COVID 19 pandemic, a set of modifications were implemented in the way it was taught. Higher education institutions in Chile were not immune to this phenomenon, and to this scenario was added a set of trends that had already been raising the need to review didactics, in terms of what and how it is taught. Different initiatives led to the development and implementation of didactic strategies that sought to solve the challenges faced by the educational system. Even though innumerable articles referring to the implementation of these didactic innovations have appeared, the evidence regarding the impact of their adaptations remains scarce. The objective of this research is to evaluate the impact of the use of the Case Method on the academic performance of the students of the calculus subject of the Business Administration Engineering degree at a Chilean higher education institution in an online context. through a difference-in-differences model using control groups generated with the Propensity Score Matching technique. The results show a positive and statistically significant effect on student grades.

RESUMEN Producto de la pandemia de COVID 19 se implementaron un conjunto de modificaciones en la forma cómo se enseñaba. Las instituciones de educación superior en Chile no estuvieron ajenas a ese fenómeno, y a este escenario se sumó un conjunto de tendencias que ya venían planteando la necesidad de revisar la didáctica, en cuánto al qué y al cómo se enseña. Diferentes iniciativas llevaron al desarrollo e implementación de estrategias didácticas que buscaron resolver los desafíos que enfrentaba el sistema educativo. Aun cuando han surgido innumerables artículos referidos a la implementación de estas innovaciones didácticas, la evidencia respecto del impacto de sus adaptaciones permanece escasa. El objetivo de la presente investigación es evaluar el impacto del uso del Método del Caso en el rendimiento académico de los estudiantes de los estudiantes de la asignatura de cálculo de la carrera Ingeniería en Administración de Empresas de una institución de educación superior chilena en un contexto online mediante un modelo de diferencias en diferencias usando grupos de control generados con la técnica de Propensity Score Matching. Los resultados muestran un efecto positivo y estadísticamente significativo en las calificaciones de los estudiantes.