We present a methodology to simulate the impact of the atmospheric models in the background particle flux on ground detectors using the Global Data Assimilation System. The methodology was within the ...ARTI simulation framework developed by the Latin American Giant Observatory Collaboration. The ground-level secondary flux simulations were performed in a tropical climate in the city of Bucaramanga, Colombia. To validate our methodology, we built monthly profiles over Malargüe between 2006 and 2011, comparing the maximum atmospheric depth, X
max
, with those calculated with the Auger atmospheric option in CORSIKA. The results show significant differences between the predefined CORSIKA atmospheres and their corresponding Global Data Assimilation System atmospheric profiles.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The ANDES Underground Laboratory is being planned and designed to be one of the largest and most shielded laboratories in the Southern Hemisphere, which will be located in the Andes Range, in the ...area of the current Paso AguaNegra that connects the provinces of San Juan (Argentina) and Elqui (Chile). The diversity of experiments that are being planned, including experiments for the direct and indirect search of dark matter and neutrino precision physics, requires a precise knowledge of the flux of high-energy atmospheric muons within the laboratory. These are produced during the interaction of astroparticles with energies between 1012and 1018eV denominated of high and ultra-high energy with the Earth’s atmosphere. In the high-energy component, muons with energies of tens of TeV can be found, capable of passing through thousands of meters of rock. Previous estimates made from reasonable assumptions about the type of rock expected in the area showed that the expected muon flux was compatible with other underground laboratories at an equivalent depth. In this work, extensive atmospheric showers flux simulations were performed at the laboratory site. Afterwards, there was a selection of those muons with sufficient energy to reach the laboratory-based on their angle of incidence and the height at which they enter the mountain. Then a transfer function was modeled using the new geological studies currently available that allow us to have a detailed model of the rock distribution inside the mountain. Finally, the interaction of these muons with the different types of rock was calculated numerically along their way to the laboratory using the continuous slowdown approximation, thus obtaining that the expected muon flux within the laboratory is 1,47±0,02 day−1m−2sr−1
Zeta Potential of Food Matrices Cano-Sarmiento, C.; Téllez-Medina, D. I.; Viveros-Contreras, R. ...
Food engineering reviews,
09/2018, Letnik:
10, Številka:
3
Journal Article
Recenzirano
Food matrices contain electrically charged particles, which interact with each other and with the media and are produced via several interface processes and mechanisms. The understanding of electric ...charge interactions is complex and essential towards the development of food systems since they can determine the type of particle-particle and particle-media interactions. They strongly affect stability, rheological behavior, sedimentation, re-dispersion, filtration, shelf life, texture, flavor, and color; thus, importantly influencing food structure and stability. One of the most useful parameters that allow the study of electric interactions in food systems is the
zeta potential
(ZP). It is possible to find a variety of laboratory instruments designed for its evaluation. ZP is an important property for the characterization of dispersed systems in which sample preparation and measuring methods play a key role to obtain reliable and reproducible results. The use of this parameter has increased in a number of fluid food systems such as alcoholic beverages, juices, extracts, coffee, milk, yoghurt, and edible films, most of which are described in this review. There is a wide amplitude in the number of relevant publications in the literature involving ZP for different products and this is reflected in the length of the different sections of this document. This work depicts a thorough review of the main theoretical principles, applications, and relevance of this parameter in food science and technology.
Alternative therapies for cancer treatment have been developed using bioactive compounds such as betulinic acid (BA). The objective of this study was to investigate the bioactivity of BA in its free ...form and compare it with its nano-encapsulated form under a skin carcinogenesis protocol in a genetically modified murine model. K14E6 and FVB mice were divided into four groups to be treated with free BA and with betulinic acid nanoemulsion (BANE). Lecithin enriched with medium chain fatty acids (MCFAs) was employed as an emulsifier to prepare the nanoemulsions with a mean droplet size of 40 nm. Skin tumors were induced by exposure to DMBA and TPA directly to the transgenic mice. Tumor development was completely inhibited by BANE and by 70% with free BA. This was validated by histological sections and the gene expression of the Cdk4 and Casp8 genes.
Gamma-Ray Bursts (GRBs) are one of the brightest transient events detected, with energies in their prompt phase ranging from keV to GeV. Theoretical models predict emissions at higher energies in the ...early times of the afterglow emission, and recently GRB190114C was the first GRB detected at TeV energies by the MAGIC experiment. The Latin American Giant Observatory (LAGO) operates a network of water Cherenkov detectors (WCD) at different sites in Latin America. Spanning over different altitudes and geomagnetic rigidity cutoffs, the geographic distribution of the LAGO sites, combined with the new electronics for control, atmospheric sensing, and data acquisition, allows the realization of diverse astrophysics studies at a regional scale. LAGO WCDs located at high altitudes possess good sensitivity to electromagnetic secondary radiation, which is the main expected signature of this kind of high-energy event on the ground. Due to the characteristics of the WCD and the wide field of view, LAGO possesses a large aperture high-duty cycle. In this work, we present the results of the sensitivity of LAGO small arrays of WCDs for the detection of events like GRB190114C. Also, we extend the study to other TeV galactic emitters, such as pulsar wind nebulas, TeV-halos, and some additional sources with unidentified categorizations. These are interesting sources to study taking advantage of the long-term monitoring capabilities of LAGO. We use a dedicated simulation process: ARTI, a toolkit developed by LAGO for high-energy air showers, MEIGA, a framework to simulate the response of the detectors, and oneDataSim, the new high-performance computing and cloud-based implementation of our simulation framework.
Resumen: El Laboratorio Subterráneo ANDES está siendo planificado y diseñado para ser uno de los laboratorios más grandes y con mayor cobertura de roca en el Hemisferio Sur, el cual estará ubicado en ...la Cordillera de los Andes, en la zona del actual Paso Agua Negra que conecta las provincias de San Juan (Argentina) y Elqui (Chile). La diversidad de experimentos que se están planificando, entre ellos experimentos de búsqueda directa e indirecta de materia oscura y física de precisión de neutrinos, requieren de un conocimiento preciso del flujo esperado de muones atmosféricos de alta energía dentro del laboratorio. Estos son producidos durante la interacción con la atmósfera terrestre de astropartículas de alta y ultra alta energía, con energías entre 1012 y 1018 eV. En la componente de alta energía pueden encontrarse muones con energías de decenas de TeV, capaces de atravesar miles de metro de roca. Estimaciones previas realizadas a partir de suposiciones razonables sobre el tipo de roca esperada en la zona, mostraron que el flujo de muones esperado era compatible con el de otros laboratorios a una profundidad equivalente. En este trabajo, se realizaron simulaciones de flujo de lluvias atmosféricas extendidas en el sitio del laboratorio. A continuación, se seleccionaron aquellos muones con energía suficiente para alcanzar al laboratorio en base a su ángulo de incidencia y a la altura a la que ingresan en la montaña. Luego se modeló una función de transferencia utilizando los nuevos estudios geológicos disponibles actualmente que permiten disponer un modelo detallado de la distribución de roca en el interior de la montaña. Finalmente, se calculó numéricamente la interacción de estos muones con los diferentes tipos de roca a lo largo de su recorrido hacia el laboratorio utilizando el modelo de desaceleración continua, obteniéndose así que el flujo de muones esperado dentro del laboratorio es de 1,47±0,02 día−1 m−2 sr−1.
Resumo Conscientes de la problemática relacionada con la motivación en el estudio de las carreras científicas, presentamos dos experiencias en las cuales se expone a estudiantes universitarios a ...ambientes, metodologías y técnicas del descubrimiento abordando problemas contemporáneos. Estas experiencias se desarrollaron en dos contextos complementarios: un curso de Introducción a la Física, en el cual se motiva a estudiantes de Física a la participación temprana en investigación, y un semillero de investigación multidisciplinario para estudiantes avanzados de pregrado en Ciencias e Ingeniería, el cual produjo incluso contribuciones a eventos internacionales. Si bien los resultados son preliminares y requieren más ediciones para ser estadísticamente significativos, consideramos que son alentadores. En ambos entornos se observó un aumento de la motivación de los estudiantes para continuar sus carreras haciendo énfasis en la investigación. En este trabajo, además de presentar el marco contextual en el cual se soportan las experiencias, describimos seis actividades concretas para vincular a los estudiantes con los ambientes de descubrimiento, las cuales creemos pueden ser replicadas en ambientes similares de otras instituciones educativas.
Abstract Being aware of the motivation problems observed in many scientific oriented careers, we present two experiences to expose college students to environments, methodologies and discovery techniques addressing contemporary problems. This experiences are developed in two complementary contexts: an Introductory Physics course, where we motivated physics students to participate in research activities, and a multidisciplinary incubator of research oriented to advanced undergraduate students of Science and Engineering (that even produced three poster presentations in international conferences). Although these are preliminary results and require additional editions to get statistical significance, we consider they are encouraging results. On both contexts we observe an increase in the students motivation to orient their careers with emphasis on research. In this work, besides the contextualization support for these experiences, we describe six specific activities to link our students to research areas, which we believe can be replicated in similar environments in other educational institutions.
Resumo Conscientes de la problemática relacionada con la motivación en el estudio de las carreras científicas, presentamos dos experiencias en las cuales se expone a estudiantes universitarios a ...ambientes, metodologías y técnicas del descubrimiento abordando problemas contemporáneos. Estas experiencias se desarrollaron en dos contextos complementarios: un curso de Introducción a la Física, en el cual se motiva a estudiantes de Física a la participación temprana en investigación, y un semillero de investigación multidisciplinario para estudiantes avanzados de pregrado en Ciencias e Ingeniería, el cual produjo incluso contribuciones a eventos internacionales. Si bien los resultados son preliminares y requieren más ediciones para ser estadísticamente significativos, consideramos que son alentadores. En ambos entornos se observó un aumento de la motivación de los estudiantes para continuar sus carreras haciendo énfasis en la investigación. En este trabajo, además de presentar el marco contextual en el cual se soportan las experiencias, describimos seis actividades concretas para vincular a los estudiantes con los ambientes de descubrimiento, las cuales creemos pueden ser replicadas en ambientes similares de otras instituciones educativas.
This paper describes a collaborative experience to empower organized communities to produce, curate and disseminate environmental data. A particular emphasis is done on the description of open ...hardware & software architecture and the processes of commissioning of the low cost Arduino-Raspberry-Pi weather station which measures: atmospheric pressure, temperature, humidity, precipitation, cloudiness, and illuminance/irradiance. The idea is to encourage more people to replicate this open-science initiative. We have started this experience training students & teachers from seven mid secondary schools through a syllabus of 12 two-hours lectures with a web-based support which exposes them to basic concepts and practices of Citizen Science and Open Data Science.
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