Preliminary Development of an Item Bank and an Adaptive Test in Mathematical Knowledge for University Students

In the last decades, the development of computerized adaptive testing (CAT) has allowed more precise measurements with a smaller number of items. In this study, we develop an item bank (IB) to generate the adaptive algorithm and simulate the functioning of CAT to assess the domains of mathematical knowledge in Argentinian university students (N=773). Data were analyzed from the Rasch model. A simulation design created with the R software was used to determine the necessary items of the IB to estimate examinee ability. Our results indicate that the IB in the domains of mathematical knowledge is adequate to be applied in CAT, especially to estimate average ability levels. The use of CAT is recommended for rapidly generating indicators of the knowledge acquired by students and to design educational strategies that enhance student performance. Results, constrains, and implications of this study are discussed.Fil: Ghio, Fernanda Belén. Universidad Nacional de Córdoba. Instituto de Investigaciones Psicológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Psicológicas; ArgentinaFil: Bruzzone, Manuel. Universidad Nacional de Córdoba. Instituto de Investigaciones Psicológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Psicológicas; ArgentinaFil: Rojas Torres, Luis. Universidad de Costa Rica. Facultad de Ciencias Sociales. Instituto de Investigaciones Psicologicas.; Costa RicaFil: Cupani, Marcos. Universidad Nacional de Córdoba. Instituto de Investigaciones Psicológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Psicológicas; Argentin

Factores biogeográficos determinantes de la distribución de Triatoma recurva en Chihuahua, México, 2014

Introduction: Triatoma recurva is a Trypanosoma cruzi vector whose distribution and biological development are determined by factors that may influence the transmission of trypanosomiasis to humans.Objective: To identify the potential spatial distribution of Triatoma recurve, as well as social factors determining its presence.Materials and methods: We used the MaxEnt software to construct ecological niche models while bioclimatic variables (WorldClim) were derived from the monthly values of temperature and precipitation to generate biologically significant variables. The resulting cartography was interpreted as suitable areas for T. recurva presence.Results: Our results showed that the precipitation during the driest month (Bio 14), the maximum temperature during the warmest month (Bio 5), and the altitude (Alt) and mean temperature during the driest quarter (Bio 9) determined T. recurva distribution area at a higher percentage evidencing its strong relationship with domestic and surrounding structures.Conclusions. This methodology can be used in other geographical contexts to locate potential sampling sites where these triatomines occur.Introducción. Triatoma recurva es un vector de Trypanosoma cruzi cuya existencia y desarrollo biológico están determinados por factores que pueden influir en la transmisión de la tripanosomiasis a los seres humanos.Objetivo. Determinar una posible distribución espacial de Triatoma recurva y algunos factores sociales que determinan su presencia.Materiales y métodos. El modelado de nicho ecológico se hizo con el programa MaxEnt empleando las variables bioclimáticas (WorldClim) derivadas de los valores mensuales de temperatura y precipitación para generar variables biológicamente significativas. La cartografía resultante evidenció áreas adecuadas para la presencia de T. recurva.Resultados. Los resultados indicaron que la precipitación del mes más seco (Bio 14), la temperatura máxima del mes más cálido (Bio 5), y la altitud (Alt) y la temperatura media del trimestre más seco (Bio 9), determinaron en mayor porcentaje el área de distribución de T. recurva, observándose que es una especie con una acentuada relación con las estructuras domésticas y circundantes.Conclusión. Esta metodología puede emplearse en otros contextos geográficos para localizar posibles sitios de muestreo de estos triatominos

Identificación de variables que impactan en la Eficiencia Energética de Secadoras de ropa.

Este artículo presenta el estudio de identificación de variables que mayor impacto tienen en la eficiencia energética de una secadora de ropa de tipo doméstico. También se presenta un análisis funcional donde se describen los procesos físicos que se llevan a cabo durante un ciclo de secado, desde la generación de calor a través de un calentador eléctrico, hasta le extracción de la humedad de ropa a través de tubos de escape. Posteriormente, se delimita el “Proceso de Secado” dentro del tambor de la secadora, como el fenómeno a entender, explicar y modelar para mejorar su eficiencia. Por medio de un diagrama de parámetro (Diagrama P) y un panel de expertos es que se entiende el proceso de secado de ropa, y son determinadas las variables de entrada que el sistema necesita; así como las de salida que el sistema entrega. A través de estudios teóricos previos es como se explica que variables físicas deberán controlarse para obtener una mejor eficiencia energética. Para validar dichos estudios teóricos previos, se plantea modelar experimentalmente el fenómeno de secado, a través de la construcción de un prototipo funcional y un diseño de experimentos (DOE). Con estas actividades se logra determinar que variables tienen el mayor impacto sobre la eficiencia energética en el proceso de secado; logrando identificar que una disminución en 15% de la humedad relativa del aire que entra a la secadora, podría ayudar a disminuir hasta en un 17% el consumo energético. También el estudio reveló las variables físicas que podrían hacer un ciclo de secado de ropa más rápido

A Primer on Resonances in Quantum Mechanics

After a pedagogical introduction to the concept of resonance in classical and quantum mechanics, some interesting applications are discussed. The subject includes resonances occurring as one of the effects of radiative reaction, the resonances involved in the refraction of electromagnetic waves by a medium with a complex refractive index, and quantum decaying systems described in terms of resonant states of the energy. Some useful mathematical approaches like the Fourier transform, the complex scaling method and the Darboux transformation are also reviewed.Comment: 28 pages, 9 figures, lectures presented at the Advanced Summer School in Physics 2008, Cinvestav, Mexic

Septic embolism due to periorbital cellulitis caused by pimple drainage

At some point in everyone’s life homemade pimple drainage has been part of the routine, especially in the early years of adult life and teenagers’ days. However, pimple drainage has its special considerations as a mild medical procedure most of the time, even more in patients with serious skin diseases. Even when it is rare to see these kinds of clinical cases in daily medical practice, here we present the case of a 22 years-old female who made (as usual) a home pimple drainage that ended up in periorbital cellulitis and septic embolism. This case highlights the importance of early recognition and appropriate management of periorbital cellulitis to prevent the development of septic embolism

Modeling the subcritical spread of cracks grown by fatigue / Modelando a propagação subcrítica de rachaduras crescidas por fadiga

The objective of this article is to mathematically model the subcritical propagation of fatigue-grown cracks. Three fatigue specimens were used, made of ASTM A 36 structural steel, which were notched in the center of the specimen to simulate a stress concentrator, and for the crack to propagate in the same plane. A three-point bending fatigue machine was used which is equipped with computer data acquisition equipment.The subcritical propagation of fatigue cracks was monitored, using the strain gage technique, and it was verified with the beach marking technique; which guaranteed the reliability of the method. With the data obtained, a vs N graph was made, and the empirical equation that governs this phenomenon was found; Likewise, derivatives were applied and the crack advance speed versus crack size was calculated; and to calculate the stress intensity factor, the Newman Raju method was applied, which is being verified by many researchers in recent years.In this way, it is possible to find a mathematical expression that modulates the fracto-mechanical behavior of the subcritical propagation of a crack, which relates the advance speed of the crack as a function of the fracture toughness evaluated as a function of the intensity factor of tensions K. With which a model similar to the one proposed for the Paris model is achieved, with the values for the parameters C = m / Cycle and m = 2.0252 that are close to the values obtained by researchers in similar materials.

La motivación de los estudiantes a participar en el Concurso Estatal de Aparatos y Experimentos de Física en Coahuila

We carried out in this work a brief survey to the high school students of the Coahuila’s state. The main goal of such survey was figuring out the motivation of the students to participate in science competition fairs related with theoretical and experimental physics. The survey was achieved during the 7th science competition fair of the state of Coahuila. This competition was carried out using the on-line and the face to face modes. According to the results in the survey, the students are motivated to participate in such event because they can increase their knowledge in physics and they also promote their creativity. Most of the students believe that the covid pandemic has affected their performance in the school to learn about physics. Despite this situation, they are considering a career in the field of physics or physics engineering. Finally, the students recommend that the award for the science fair should be cash, scientific travels or acceptance letters from prestigious universities to study physics.En este trabajo se realiza una breve encuesta dirigida a estudiantes de bachillerato del estado de Coahuila de Zaragoza para saber su motivación de participar en competiciones y/o Concurso de Física Experimental y Teórica. Esto en el marco de la realización del 7 Concurso Estatal de Aparatos de Experimentos de Física del estado de Coahuila el cual se llevó a cabo el pasado 23 de abril de 2021 en modalidad hibrida: presencial y en línea. Los resultados de la breve encuesta, indican que los estudiantes se motivan en este tipo de concursos debido al desarrollo de habilidades en la física, fomento de creatividad, y competitividad. Así mismo, manifiestan que la pandemia de Covid-19 si les ha afectado en el estudio de la Física, aunque una gran cantidad de estudiantes tiene pensado estudiar carreras relacionadas con la Ingeniería que involucran la Física como una de sus materias básicas. Finalmente, los estudiantes sugieren que los premios a este tipo de Concursos de Física debieran ser recomendaciones para ingresar en Universidades prestigiosas, dinero en efectivo o viajes científicos

Aplicación del programa de entrenamiento nous para mejorar habilidades sociales, en alumnos del primer año de la Facultad De Ciencias de la Educación de la UNHEVAL, Huánuco 2005-2006

La investigación, consistió en comprobar la efectividad del Programa de Entrenamiento de habilidades sociales “Nous”, en los estudiantes del primer año de diferentes especialidades en la Facultad de Educación de la Universidad Nacional Hermilio valdizan (UNHEVAL), la muestra de estudio fue 82 alumnos, con diseño de un solo grupo y con pre y postest. Luego de haber sido sometidos al tratamiento con el programa “Nous”, los alumnos cambiaron positivamente en sus comportamientos sociales, se mostraron empáticos, asertivos, comunicativos, lo que indica una mejora considerable de sus habilidades sociales

High-sensitivity c-reactive protein epidemiological behavior in adult individuals from Maracaibo, Venezuela

Objectives: High-sensitivity C-Reactive Protein (hs-CRP) is one of the most applied inflammation markers; therefore, the main objective of this research is to evaluate its epidemiological behavior in adult subjects of the Maracaibo City, Venezuela. Materials and Methods: A total of 1,422 subjects, 704 women (49.5%) and 718 men (50.5%), were enrolled in the Maracaibo City Metabolic Syndrome Prevalence Study. The results were expressed as medians and inter-quartile ranges (p25-p75). Differences were determined through the Mann-Whitney U test and one-way ANOVA test with the Bonferroni adjustment. A multiple logistic regression model was designed for the analysis of the main factors associated with high serum hs-CRP levels. Results: Overall hs-CRP median was 0,.372 mg/L (0.126- 0.765 mg/L), 0,382 mg/L (0.122-0.829 mg/L) for women and 0.365 mg/L (0.133-0.712 mg/L) for men; p=0.616. An increasing pattern was observed in hs-CRP concentrations through age, BMI, waist circumference and HOMA2-IR categories. After adjusting for independent variables, a greater risk for elevated hs-CRP levels was observed with female gender, hypertriacylglyceridemia, obesity, diagnosis of metabolic syndrome and very large waist circumference values. Conclusions: Elevated hs-CRP levels are related to the metabolic syndrome but not with each of their separate components, being a greater waist circumference one of the more important risk factors, but only at values much higher than those proposed for our population.&nbsp

Cigarette smoking and metabolic syndrome components: a cross-sectional study from Maracaibo City, Venezuela [version 3; referees: 2 approved]

Background: A growing body of evidence suggests that cigarette smoking can cause the onset of metabolic syndrome prior to cardiovascular diseases. Therefore, the objective of this study was to evaluate the relationship between smoking habit and metabolic syndrome components in an adult population from Maracaibo city, Venezuela. Methods: The Maracaibo City Metabolic Syndrome Prevalence Study is a descriptive, cross-sectional study with random and multi-stage sampling. In this sub-study, 2212 adults from both genders were selected. On the basis of their medical background, they were classified as smokers, non-smokers and former smokers. Metabolic syndrome was defined according to Harmonizing 2009 criteria, using population-specific abdominal circumference cut-off points. The association between risk factors was evaluated using a logistic regression model. Results: In the studied population, 14.8% were smokers, 15.4% were former smokers. In the multivariate analysis, the presence of metabolic syndrome (smokers: OR, 1.54; 95% CI, 1.11–2.14; p=0.010) and its components were related to cigarette smoking, with the exception of hyperglycemia. High blood pressure was inversely associated with current smoking status (smokers: OR, 0.70 (0.51–0.95); p=0.025). Conclusion: Cigarette smoking represents a related factor with metabolic syndrome, being associated with low high-density lipoprotein-cholesterol, increased abdominal circumference and elevated triacylglyceride levels. Former smokers did not present a greater risk for developing this metabolic disease when compared to non-smokers. The effect of avoiding this habit should be evaluated in future studies in our population