Control administrativo docente para mejorar el aprendizaje en el curso de química en el nivel medio superior

[Tesis] (Maestro en Enseñanza de las Ciencias con Especialidad en Química) U.A.N.L.UANLhttp://www.uanl.mx

Comercio de Marfil: el alto precio de un negocio que amenaza las especies

Treball presentat a l'assignatura de Deontologia i Veterinària Legal (21223

Techno-Functional Properties of New Andean Ingredients: Maca (Lepidium meyenii) and Amaranth (Amaranthus caudatus)

[EN] The use of flours derived from Andean products could be an alternative flour. Molecules with a potential beneficial effect on human health have been reported in maca (Lepidium meyenii) (dietary fibre, Mg, Ca, K, functional polysaccharides, etc.) and amaranth (Amaranthus caudatus) (squalene, linoleic acid, P, Ca, K, Mg, dietary fibre, etc.). However, from an industrial point of view, these new ingredients must be characterized in their techno-functional properties. The objective of this work was to analyze the techno-functional parameters of the amaranth and maca flours (NW) and whole (W) flours, in terms of water holding capacity (WHC, g/g), oil holding capacity (OHC, g/g), swelling capacity (SC, mL/g), foaming capacity (FC, %) and emulsifying capacity (EC, mL). The particle size of flours was also analyzed. The results indicated that the highest values for WHC were obtained in maca flour (NW) with 2.45 g of retained water/g of sample. The highest values of OHC were observed for NW flours (around 1.02 g of absorbed oil/g of sample). Meanwhile, for the variables FC and EC, the highest values were obtained for amaranth (NW) with 16.67% and amaranth (W) with 139.44 mL, respectively. Therefore, the results obtained allow us to consider the incorporation of these types of flours to different food products, knowing their effect on WHC, OHC, EC, and pH, and therefore being able to modify the processes concerning the traditional ones. This is especially interesting in the case of the meat products elaboration process in which these parameters could be critical, with the addition of these type of flours.Alarcon-Garcia, MA.; Perez-Alvarez, JA.; López-Vargas, JH.; Pagán Moreno, MJ. (2021). Techno-Functional Properties of New Andean Ingredients: Maca (Lepidium meyenii) and Amaranth (Amaranthus caudatus). Proceedings. 70(1):1-7. https://doi.org/10.3390/foods_2020-07744S1770

Meat Snacks Consumption: Aspects That the Consumer Looks for to Consider Them a Healthy Food

[EN] In recent years, the consumption of snacks has increased substantially. Analysis of consumption trends of this kind of food through the use of surveys would allow matching of the supply to the demand. The objective of the present work was to study snacks and meat snacks consumption, and to analyze which consumers¿ preferences of these products were considered as healthy. An online survey was conducted with 234 consumers where they were asked about which type of snacks they consumed, frequency of consumption, the main characteristics that they look for in these types of foods, and what they consider a healthy snack should have. The results showed that the most important motivations for acquisition and consumption of snacks were those related to convenience, while for meat snacks they were those related to acceptability, above convenience and sociability. The most consumed snacks were, in descending order: fruits, dairy, nuts/seeds, coffee, cookies, and meat snacks. More than 50% of the respondents consumed them from once a day to two to three times a week. As for meat snacks, the most consumed were dehydrated meats for most of those surveyed. For consumers, a healthy meat snack should be rich in protein and low in saltAlarcón-Garcia, MA.; Perez-Alvarez, JA.; López-Vargas, JH.; Pagán Moreno, MJ. (2021). Meat Snacks Consumption: Aspects That the Consumer Looks for to Consider Them a Healthy Food. Proceedings. 70(1):1-6. https://doi.org/10.3390/foods_2020-07738S1670

Estilos de aprendizaje y rendimiento académico de los estudiantes de la Facultad de Ingeniería de Sistemas e Informática de la Universidad Nacional de la Amazonía Peruana-Iquitos 2009

La búsqueda de evidencia de relación entre estilos de aprendizaje y el rendimiento académico de los estudiantes de la Facultad de Ingeniería de Sistemas e Informática de la Universidad Nacional de la Amazonía Peruana en la ciudad de !quitos- 2009 permitirá reflexionar, como punto de partida, en tomo al proceso de enseñanza-aprendizaje y como consecuencia implantar estrategias que faciliten el aprendizaje a los estudiantes. En tal sentido, la presente investigación tuvo como objetivo determinar la relación entre los estilos de aprendizaje y el rendimiento académico de los estudiantes del 1 semestre- 2009 de la Facultad de Ingeniería de Sistemas e Informática (FISI) de la Universidad Nacional de la Amazonía Peruana (UNAP) - Iquitos. La metodología empleada incluyó el éstudio de tipo cuantitativo, aplicada, prospectivo, transversal, correlaciona}, se empleó el diseño de nivel descriptivo correlacional. El tamaño de la población fue de 211 estudiantes, la muestra estuvo constituida por 137 estudiantes con muestreo probabilístico de tipo estratificado con afijación proporcional. Se asignó los sujetos al azar, utilizando la tabla de números aleatorios. Los instrumentos empleados fueron, para los estilos de aprendizaje, el cuestionario de Honey - Alonso de estilos de Aprendizaje (CHAEA) y para el rendimiento académico se utilizó las fichas electrónicas de información académica. Los hallazgos relevantes fueron: El 59.90% de estudiantes tienen estilo reflexivo y 62.05 % de estudiantes lograron rendimiento medio-regular. Para la probar la hipótesis se aplicó la estadística no paramétrica Ji cuadrado obteniéndose X2 =0.2743, gl=2, p=0.8718 y a=0.05, rechazando la hipótesis de estudio y concluyendo que no existe relación significativa entre estilos de aprendizaje y rendimiento académico de los estudiantes de la FISI- UNAP- Iquitos 2009.Looking for the factual relationship between the students learning of the Engineering System and Computer Faculty and their academic performance of The Amazon Peruvian National University in !quitos (city) -2009 willlet us think as a starting point dealing with teaching-learning so we will introduce strategies for easy learning. For that reason, the object of this research is to determínate the relationship between the learning styles and their academic performance ofthe first semester students- 2009 ofthe Engineering System and Computer Faculty (FISI) of the Amazon Peruvian National University (UNAP)- Iquitos. This investigation is of quantity, applied, prospective, transversal, co relational type, but the descriptive co relational type was used. The population is constituted by 211 students; the sample is constituted by 137 students as a probability sample of divided proportional type. The agents were selected at random using the random numbers table. The instrument for the learning styles was the Honey survey- learning styles Alonso (CHAEA) and for the academic performance was the electronic academic information card. The relevant seeks were: 59.90% of the students have reflexive styles and 62.05% got medium-regular performance. The non parameter statistics square "Ji" was used to probe the hypothesis. We got x2 =0.2743, gl=2, p=0.8718 and a=0.05,'rejecting the hypothesis of this research. As a result, there is not any meaningful relationship between the learning styles and their academic performance ofthe FISI-UNAP-Iquitos 2009.Tesi

Effects of soft and hard magnetic particles on the mechanical performance of ultra-soft magnetorheological elastomers

Magnetorheological elastomers (MREs) mechanically respond to external magnetic stimuli by changing their mechanical properties and/or changing their shape. Recent studies have shown the great potential of MREs when manufactured with an extremely soft matrix and soft-magnetic particles. Under the application of an external magnetic field, such MREs present significant mechanical stiffening, and when the magnetic field is off, they show a softer response, being these alternative states fully reversible. Although softmagnetic particles are suitable for their high magnetic susceptibility, they require the magnetic actuation to remain constant in order to achieve the magneto-mechanical stiffening. Here, we present an alternative solution based on hard-magnetic MREs to provide stiffening responses that can be sustained along time without the need of keeping the external magnetic field on. To this end, we manufacture novel extremely soft hardmagnetic MREs (stiffness in the order of 1 kPa) and characterise them under magneto-mechanical shear and confined magnetic expansion deformation modes, providing a comparison framework with the soft-magnetic counterparts. The extremely soft nature of the matrix allows for easily activating the magneto-mechanical couplings under external magnetic actuation. In this regard, we provide a novel approach by setting the magnetic actuation below the fully magnetic saturating field. In addition, free deformation tests provide hints on the microstructural transmission of torques from the hard-magnetic particles to the viscoelastic carrier matrix, resulting in macroscopic geometrical effects and complex functional morphological changes. Keywords: Magnetorheological elastomers (MREs), Magneto-mechanics, Experimental characterisation, Hard-magnetics MRE, Multifunctional materials, Magnetic propertiesThe authors acknowledge support from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No. 947723, project: 4D-BIOMAP). The authors acknowledge support from MCIN/ AEI /10.13039/501100011033 under Grant number PID2020- 117894GA-I00. MAMM acknowledges support from the Ministerio de Ciencia, Innovacion y Universidades, Spain (FPU19/03874) and DGG acknowledges support from the Talent Attraction grant (CM 2018 - 2018-T2/IND-9992) from the Comunidad de Madrid. MH acknowledges the funding through an EPSRC Impact Acceleration Award (EP/R511614/1)

Estudio mecánico del asfalto modificado con polímeros y cueros que son utilizados en la elaboración del calzado

This paper is the result of a cooperation between the Administrative Department of Science, Technology and Innovation (COLCIENCIAS) and Research Group of Pavements and Enginering Materials of the Catholic University of Colombia. The research goal was to understand the physicalmechanical properties of the asphalt cement modified with polymers and leather and also to characterize its chemical properties. The leather used for this modification comes from waste combat boots from the Colombian Army. Several samples were prepared with different combinations of percentages of each of the polymers and leather for the modification of the asphalt cement. The characterization of this material includes stiffness, fluidity and stability in order to find out the percentage with the better performance. After multiple tests, the results show improvements in the mechanical properties of the modified asphalt and leaves the door open for the proper use of polluting material that contributes to reduce the environmental impact.Este artículo es resultado de un trabajo de cooperación entre el Departamento Administrativo de Ciencia, Tecnología e Innovación (Colciencias) y el Grupo de Investigación de Pavimentos y Materiales de Ingeniería de la Universidad Católica de Colombia, cuya finalidad fue entender el comportamiento físico-mecánico del cemento asfáltico modificado con polímeros y cueros, así como caracterizar el material modificado en términos de sus propiedades químicas. En concreto, se toma como material de investigación las botas de combate desechadas por los militares en Colombia, y se procede a la elaboración de muestras con diferentes combinaciones de porcentajes de cada uno de los polímeros y cueros para la modificación del cemento asfáltico. Se realiza también la caracterización de este material y sus propiedades físicas de rigidez, fluidez y estabilidad, de lo cual se obtiene el porcentaje de mejor comportamiento. Luego de múltiples pruebas, los resultados obtenidos muestran mejoras en las propiedades mecánicas de la mezcla asfáltica modificada y deja la puerta abierta para un aprovechamiento adecuado de residuos contaminantes que contribuyan a reducir el impacto ambiental.

Signal-to-noise ratio of the MEG signal after preprocessing

Background Magnetoencephalography (MEG) provides a direct measure of brain activity with high combined spatiotemporal resolution. Preprocessing is necessary to reduce contributions from environmental interference and biological noise. New method The effect on the signal-to-noise ratio of different preprocessing techniques is evaluated. The signal-to-noise ratio (SNR) was defined as the ratio between the mean signal amplitude (evoked field) and the standard error of the mean over trials. Results Recordings from 26 subjects obtained during and event-related visual paradigm with an Elekta MEG scanner were employed. Two methods were considered as first-step noise reduction: Signal Space Separation and temporal Signal Space Separation, which decompose the signal into components with origin inside and outside the head. Both algorithm increased the SNR by approximately 100%. Epoch-based methods, aimed at identifying and rejecting epochs containing eye blinks, muscular artifacts and sensor jumps provided an SNR improvement of 5–10%. Decomposition methods evaluated were independent component analysis (ICA) and second-order blind identification (SOBI). The increase in SNR was of about 36% with ICA and 33% with SOBI. Comparison with existing methods No previous systematic evaluation of the effect of the typical preprocessing steps in the SNR of the MEG signal has been performed. Conclusions The application of either SSS or tSSS is mandatory in Elekta systems. No significant differences were found between the two. While epoch-based methods have been routinely applied the less often considered decomposition methods were clearly superior and therefore their use seems advisable

Mitochondrial Haplogroups Define Two Phenotypes of Osteoarthritis

Objective: To assess a mitochondrion-related phenotype in patients with osteoarthritis (OA). Methods: Serum levels of the following OA-related biomarkers: matrix metalloproteinase-1 (MMP-1); MMP-3; MMP-13; myeloperoxidase (MPO); a peptide of the alpha-helical region of type II collagen, Coll2-1, and its nitrated form Coll2-1NO2; a C-terminal neoepitope generated by the collagenase-mediated cleavage of collagen type II triple helix, C2C; the C-propeptide of collagen type II, CPII; hyaluronic acid (HA); human cartilage glycoprotein 39, YKL-40; cartilage oligomeric matrix protein; and cathepsin K were analyzed in 48 OA patients and 52 healthy controls carrying the haplogroups H and J. Logistic regression models and receiver operating characteristic (ROC) curves were performed to predict the onset of OA. Results: MMP-13 was the only biomarker significantly increased in OA patients compared to healthy controls in both haplogroups H and J. The collagen type II biomarkers, Coll2-1, Coll2-1NO2, the Coll2-1NO2/Coll2-1 ratio, C2C, CPII, and the C2C:CPII ratio were significantly increased in OA patients carrying haplogroup H compared to OA carriers of the haplogroup J. Two logistic regression models for diagnosis were constructed and adjusted for age, gender, and body mass index. For haplogroup H, the biomarkers significantly associated with OA were MMP-13 and Coll2-1; the area under the curve (AUC) of the ROC curve for this model was 0.952 (95% CI = 0.892–1.012). For haplogroup J, the only biomarker significantly associated with OA was MMP-13; the AUC for this model was 0.895 (95% CI = 0.801–0.989). Conclusion: The mitochondrial DNA haplogroups are potential complementary candidates for biomarkers of OA; their genotyping in conjunction with the assessment of classical protein molecular markers is recommended