Escuela de Ciencias

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    Análisis físico del minuto 120 del partido Chile-Brasil en el Mundial de Fútbol 2014
    (2015-12) Echiburu, Mauricio
    Este trabajo presenta el análisis, desde un punto de vista físico, de la última jugada del alargue del encuentro entre Chile y Brasil, en el Mundial de Fútbol 2014. En dicho partido, el jugador chileno Mauricio Pinilla estrelló el balón en el larguero del arco de Brasil obligando a un alargue a penales. El análisis de la jugada comprende un estudio sobre el movimiento del balón y su posterior rebote en el arco, determinando las velocidades a través de la observación de videos de la jugada, y de estimaciones razonables para la situación. Además, se realiza un análisis de la fuerza de arrastre del aire sobre el balón para la jugada, obteniendo de ello cálculos de la energía cinética del balón antes y después del rebote, para luego estimar la fuerza y deformación que actúa sobre el balón. Todo este análisis se desarrolló con información y tecnología disponible para cualquier persona, de forma que los resultados sean replicables en el aula de clases. Por esto último se sugieren actividades docentes a desarrollar utilizando este análisis como base, para trabajar diferentes fenómenos de la Física, desde una mirada más cercana para los estudiantes.
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    Glucagon-like peptide 1 receptor activation regulates cocaine actions and dopamine homeostasis in the lateral septum by decreasing arachidonic acid levels
    (2016) Reddy, IA; Pino, JA; Weikop, P; Osses, N; Sørensen, G; Bering, T; Valle, C; Bluett, RJ; Erreger, K; Wortwein, G; Reyes, JG; Graham, D; Stanwood, GD; Hackett, TA; Fink-Jensen, A; Torres, GE; Galli, A; Patel, S
    Agonism of the glucagon-like peptide 1 (GLP-1) receptor (GLP-1R) has been effective at treating aspects of addictive behavior for a number of abused substances, including cocaine. However, the molecular mechanisms and brain circuits underlying the therapeutic effects of GLP-1R signaling on cocaine actions remain elusive. Recent evidence has revealed that endogenous signaling at the GLP-1R within the forebrain lateral septum (LS) acts to reduce cocaine-induced locomotion and cocaine conditioned place preference, both considered dopamine (DA)-associated behaviors. DA terminals project from the ventral tegmental area to the LS and express the DA transporter (DAT). Cocaine acts by altering DA bioavailability by targeting the DAT. Therefore, GLP-1R signaling might exert effects on DAT to account for its regulation of cocaine-induced behaviors. We show that the GLP-1R is highly expressed within the LS. GLP-1, in LS slices, significantly enhances DAT surface expression and DAT function. Exenatide (Ex-4), a long-lasting synthetic analog of GLP-1 abolished cocaine-induced elevation of DA. Interestingly, acute administration of Ex-4 reduces septal expression of the retrograde messenger 2-arachidonylglycerol (2-AG), as well as a product of its presynaptic degradation, arachidonic acid (AA). Notably, AA reduces septal DAT function pointing to AA as a novel regulator of central DA homeostasis. We further show that AA oxidation product γ-ketoaldehyde (γ-KA) forms adducts with the DAT and reduces DAT plasma membrane expression and function. These results support a mechanism in which postsynaptic septal GLP-1R activation regulates 2-AG levels to alter presynaptic DA homeostasis and cocaine actions through AA.
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    Frequency and coinfection between genotypes of human papillomavirus in a population of asymptomatic women in northern Peru
    (2018) Costa, Luis E.; Ponce-Benavente, Luis; Rejas-Pinelo, Patricia; Aguilar-Luis, Miguel Angel; Palomares-Reyes, Carlos; Becerra-Goicochea, Lorena; Pinillos-Vilca, Luis; Silva-Caso, Wilmer; Weilg, Pablo; Alvitrez-Arana, Juan; Bazán-Mayra, Jorge; del Valle-Mendoza, Juana
    Objective: Describe the prevalence of HPV genotypes via PCR and DNA sequencing in 397 women who attended to the gynecological outpatient center in the Hospital Regional Docente de Cajamarca from March to September 2017./ Results: A positive PCR result for HPV was observed in 121 cervical samples. A high-risk genotype was found in 63.6% (77/121) of patients, a probably oncogenic type in 23.1% (28/121) and a low-risk type in 7.4%. Among the high-risk genotypes, HPV-31 was the most common one present in 20% (21/77), followed by HPV-16 in 11.4% (12/77). Coinfections between two or more genotypes were observed in 12 cases.
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    Identification of infection by Chikungunya, Zika, and Dengue in an area of the Peruvian coast. Molecular diagnosis and clinical characteristics.
    (2018) Sánchez-Carbonel, José; Tantaléan-Yépez, Derek; Aguilar-Luis, Miguel Angel; Silva-Caso, Wilmer; Weilg, Pablo; Vásquez-Achaya, Fernando; Costa, Luis; Martins-Luna, Johanna; Sandoval, Isabel; del Valle-Mendoza, Juana
    Objective: To assess the presence of Dengue, Chikungunya, and Zika in serum samples of patients with acute febrile illness in Piura, Peru and describe the most common clinical features./Results: Dengue was the most common arbovirus detected in 170/496 (34.3%), followed by Zika in 39/496 (7.9%) and Chikungunya in 23/496 (4.6%). Among the 170 samples positive for Dengue, serotype 2 was the most predominant type present in 97/170 (57.1%) of samples, followed by the serotype 3 in 9/170 (5.3%). Headaches, muscle pain, and joint pain were the most common symptoms associated with fever in patients with Dengue and Zika. No symptoms predominance was observed in patients with Chikungunya. Dengue is considered the most frequent arbovirus in Peru and the number of cases has increased dramatically in the last 5 years. However, it is not the only arbovirus that circulates along the northern coast of Peru. It has also been determined the presence of Zika and Chikungunya in our population, which may suggest the circulation of other arboviruses that have not been detected.
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    Motion analysis of kinetic impact projectiles for physics education in real context
    (2020-04-16) Hernández, Carla V.; Echiburu, Mauricio A.; Humire, Fernando R.; Mosso, Edward F.
    The article presents a proposal to contextualize the study of movement in first courses of univer- sity physics, as a contribution to decision-making in situations of a social nature. For this, the case of the use of kinetic impact projectiles and the actual data provided by official sources is considered. This information is used in an object motion model describing the kinematic characteristics of a spherical projectile (a rubber bullet). For these purposes, a number Reynolds Re ≫ 1 was used, which allows applying a nonlinear motion equation to find the velocity and impact energy per unit area of projectile. Results and analysis of this model can generate an interesting discussion in the classroom about the need to build protocols for the use of kinetic impact projectiles, and the importance of using scientific knowledge in social conflicts.
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    Análisis bibliométrico sobre Educación Financiera en Educación Primaria
    (2020-05-31) Puraivan-Huenuman, Eduardo; Ferrada, Cristian; Díaz-Levicoy, Danilo; Silva-Díaz, Francisco
    La organización curricular de diferentes países está en constante cambio, con el foco puesto, principalmente, en el desarrollo de diversas competencias en los futuros ciudadanos. La Organización para la Cooperación y el Desarrollo Económico ha entregado una serie de orientaciones respecto a formación en competencias, una de ellas es la financiera. En este sentido, el objetivo del estudio es analizar la literatura científica alojada en la base de datos Scopus relacionada con la Educación Financiera en Educación Primaria. Para ello, se realiza un estudio cuantitativo, de nivel descriptivo y tipo bibliométrico, que permite conocer la situación actual respecto de esta temática. El análisis se realiza mediante las propias métricas de Scopus y el uso del software Bibliometrix. Los resultados indican que, mediante las palabras clave utilizadas, se encontraron 130 artículos, siendo Estados Unidos y Europa los territorios geográficos de mayor producción, el año 2019 como el de notable cantidad de investigaciones, conjuntamente al área de las ciencias-matemática congregan 55,1% de éstas, en el lapsus de los 48 años investigados. En conclusión, el estudio proporciona evidencia sobre la poca productividad, dejando de manifiesto la irrisoria proliferación de esta línea de estudio, un área factible de mejorar y extrapolar a Educación Secundaria
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    Forest-Genetic method to optimize parameter design of multiresponse experiment
    (2020-08-27) Villa-Murillo, Adriana; Carrión, Andrés; Sozzi, Antonio
    We propose a methodology for the improvement of the parameter design that consists of the combination ofRandom Forest (RF) with Genetic Algorithms (GA) in 3 phases: normalization, modelling and optimization.The first phase corresponds to the previous preparation of the data set by using normalization functions. In thesecond phase, we designed a modelling scheme adjusted to multiple quality characteristics and we have called itMultivariate Random Forest (MRF) for the determination of the objective function. Finally, in the third phase,we obtained the optimal combination of parameter levels with the integration of properties of our modellingscheme and desirability functions in the establishment of the corresponding GA. Two illustrative cases allow us tocompare and validate the virtues of our methodology versus other proposals involving Artificial Neural Networks(ANN) and Simulated Annealing (SA).
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    ConCiencia T01E01: Radio Astronomía
    (Universidad Viña del Mar, 2020-10-02) Parra, Rodrigo; Rojas, Eva; Echiburu, Mauricio
    El radio astrónomo de APEX, Rodrigo Parra, conversa junto a los académicos del Departamento de Ciencias Básicas de la Universidad Viña del Mar, Eva Rojas y Mauricio Echiburu.
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    ConCiencia T01E02: Neurociencia
    (Universidad Viña del Mar, 2020-10-09) Mora, Soraya; Rojas, Eva; Echiburu, Mauricio
    La profesora de física y estudiante de posgrado en Neurociencia, Soraya Mora, conversa junto a los académicos Aliro Maulen y Mauricio Echiburu sobre como la Neurociencia se relaciona con la visión y como modelar el ojo humano.
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    ConCiencia T01E03: Histología
    (Universidad Viña del Mar, 2020-10-29) Maulen, Aliro; Gaete, Jonny; Escalona, Eduardo; Echiburu, Mauricio
    Junto a los académicos Jonny Gaete y Eduardo Escalona, conversamos con el Histólogo de la UVM Aliro Maulén. Él nos explica a qué se dedica la histología y cuales son los desafíos actuales y futuros que enfrenta el laboratorio que lidera dentro de la Universidad.
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    ConCiencia T01E04: Bibliotecología
    (Universidad Viña del Mar, 2020-11-04) Reyes-Lillo, Danilo; Escalona, Eduardo; Gaete, Jonny; Echiburu, Mauricio
    Conversamos con Danilo Reyes, bibliotecólogo de la UVM y creador de la web INFOXICADOS, quien nos contó sobre la búsqueda de la información en los tiempos actuales.
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    ConCiencia T01E05: Neutrinos
    (Universidad Viña del Mar, 2020-11-10) Helo, Juan Carlos; Rojas, Eva; Escalona, Eduardo; Echiburu, Mauricio
    El académico de la Universidad de la Serena, Juan Carlos Helo, habla sobre estas casi indetectables partículas. Nos acompañan en este episodio los académicos del DCB de la UVM Eva Rojas y Eduardo Escalona.
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    ConCiencia T01E06: Discos protoplanetarios
    (Universidad Viña del Mar, 2020-11-19) Montecinos, Matías; Escalona, Eduardo; Rodriguez, Neumarino; Echiburu, Mauricio
    En este episodio conversamos con el astrofísico Matías Montecinos sobre la investigación de sistemas planetarios. Nos acompañan en este episodio los académicos del DCB de la UVM Neumarino Rodríguez y Eduardo Escalona.
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    ConCiencia T01E07: Medio Ambiente
    (Universidad Viña del Mar, 2020-12-22) Mena, Marcelo; Rojas, Eva; Escalona, Eduardo; Echiburu, Mauricio
    En este episodio conversamos con el Ingeniero Civil Bioquímico Marcelo Mena sobre la matriz energética del país y su visión del futuro.
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    GDAS atmospheric models in astroparticle shower simulations
    (2021) Grisales-Casadiegos, J.; Sarmiento-Cano, C.; Núñez, Luis A.; LAGO Collaboration
    Atmospheric conditions affect the development of cascades of secondary particles produced by primary cosmic rays. Global Data Assimilation System, implementing atmospheric models based on meteorological measurements and numerical weather predictions, could significantly improve the outcomes of the simulations for extensive air showers. In this work, we present a methodology to simulate the effect of the atmospheric models in secondary particle flux at the Earth’s surface. The method was implemented for Bucaramanga-Colombia, using ARTI: a complete computational framework developed by the Latin American Giant Observatory Collaboration to estimate the particle spectra on Water Cherenkov Detectors depending on the geographical coordinates. We observe differences in the total flux that varies monthly concerning the subtropical summer atmospheric profile as preliminary results.
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    A Hybrid Artificial Intelligence Model for Aeneolamia varia (Hemiptera: Cercopidae) Populations in Sugarcane Crops
    (2021) Figueredo, Luis; Villa-Murillo, Adriana; Colmenarez, Yelitza; Vásquez, Carlos
    Sugarcane spittlebugs are considered important pests in sugarcane crops ranging from the southeastern United States to northern Argentina. To evaluate the effects of climate variables on adult populations of Aeneolamia varia (Fabricius) (Hemiptera: Cercopidae), a 3-yr monitoring study was carried out in sugarcane fields at weeklong intervals during the rainy season (May to November 2005–2007). The resulting data were analyzed using the univariate Forest-Genetic method. The best predictive model explained 75.8% variability in physiological damage threshold. It predicted that the main climatic factors influencing the adult population would be, in order of importance, evaporation; evapotranspiration by 0.5; evapotranspiration, cloudiness at 2:00 p.m.; average sunshine and relative humidity at 8:00 a.m. The optimization of the predictive model established that the lower and upper limits of the climatic variables produced a threshold in the population development rate of 184 to 267 adult insects under the agroecological conditions of the study area. These results provide a new perspective on decision-making in the preventive management of A. varia adults in sugarcane crops.
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    Forbush decrease on September 6-13, 2017 observed by the Tanca water-Cherenkov detector
    (2021) de Aguiar, Renan; Campos Fauth, Anderson; LAGO Collaboration
    Solar activity was intense in September 2017 and its effects were observed in different detectors placed at the Earth’s surface. Three halo Coronal Mass Ejections (CME) hit the planet and caused magnetic storms. The effects of the CMEs on the flux of galactic cosmic rays at ground level were observed by the Tanca detector, which is one of the water-Cherenkov detectors (WCD) that make up the Latin American Giant Observatory (LAGO). In this paper we present the detection of Forbush events observed by Tanca during the month of September 2017. This WCD is installed on the campus of the University of Campinas, in Brazil, having three photomultiplier tubes that detect Cherenkov photons produced by cosmic radiation in 11400 liters of ultra pure water. We present the description and performance of the experimental apparatus and the observation on days 6th, 8th and 13th of the Forbush events originated by the CMEs. A decrease in the cosmic rays flux due to a stream inTeraction region was also observed on 14th September. These results were compared with observations made by neutron monitors and indices of the Earth’s magnetic activity.
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    ConCiencia T01E08: Producción de Litio en Chile
    (Universidad Viña del Mar, 2021-01-05) Espinoza, Daniel; Rojas, Guillermo; Escalona, Eduardo; Echiburu, Mauricio
    Los académicos Eduardo Escalona, Guillermo Rojas y Mauricio Echiburu, conversaron con el Ingeniero Civil en Industrias mención química, Daniel Espinoza, quien se desempeñó como Ingeniero de producción en una planta de litio al norte de nuestro país.
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    ConCiencia T01E09: Ciencia y Género
    (Universidad Viña del Mar, 2021-01-08) Hernández, Carla; Rojas, Eva; Maulen, Aliro; Escalona, Eduardo; Echiburu, Mauricio
    Los académicos Eva Rojas, Eduardo Escalona, Mauricio Echiburu y Aliro Maulen conversaron con la Doctora de la USACH Carla Hernández, sobre temas de equidad de género en ciencias.
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    ConCiencia T01E10: Simetrías
    (Universidad Viña del Mar, 2021-03-05) Pino, Miguel; Escalona, Eduardo; Echiburu, Mauricio
    Los académicos Mauricio Echiburu y Eduardo Escalona conversaron con el Doctora de la USACH Miguel Pino, sobre simetrías y su aplicación en la física.