Enseñanza del cálculo con animaciones

Este trabajo tiene como propósito mostrar, con ejemplos, las ventajas de utilizar un software en la enseñanza de las Matemáticas. Se pone más énfasis en las animaciones, pues con éstas podemos simular o reproducir una gran variedad de problemas de Cálculo. Con esto el alumno tiene la oportunidad de visualizar mejor los conceptos del Cálculo, además puede ver para qué sirve resolver una ecuación, una integral, una derivada, etc. Esta utilidad y visualidad es fundamental para un alumno, pues es de esta forma como puede empezar a interesarse por la Matemática

Reproductive biology of little tunny Euthynnus alletteratus (Rafinesque, 1810) in the southwest Gulf of Mexico

The aim of this study was to describe the reproductive dynamic of Euthynnus alletteratus in the southwest Gulf of Mexico. The annual variation of the volume fraction occupied by gametes and tissues in gonads were related with main body indexes, such as the gonadosomatic index (IG), the hepatosomatic index (IH), and the nutrition index (IN), and compared with the sea surface temperature. A total of 951 E. alletteratus individuals were sampled, where a sex ratio of 1:1 and a size interval strongly skewed towards organisms with a fork length (LF) of 36–40 cm were observed. The IG showed an increase from March to September with maximum values in April and July. Two clearly defined peaks were observed, and they were consistent with the histological analysis, where the percentage of ripe gametes predominated from April to September. The optimum thermal window for reproductive activity was from 24 to 28 °C. The size of first sex maturity was 34.35 cm of LF for males and 34.60 (LF) for females, without significant difference between sexes

Systematic Review: Analysis of the economic modeling of biodiversity in rural agricultural households, recommendations for future reports

[ES] Los modelos de agricultura familiar, han sido utilizados para analizar ex-ante diferentes políticas; sin embargo, se desconoce el estado del arte con relación a la evaluación de la biodiversidad dentro de estos modelos. Por esta razón, se desarrolló una revisión sistemática de modelos de agricultura familiar que integren la variable “biodiversidad”. Para tal efecto, se consultaron buscadores especializa-dos, aplicando una estrategia de búsqueda genérica, que permitió identificar 1420 artículos, de los cuales solo 23 fueron seleccionados en base a criterios de inclusión específicos. Se evidencia un vacío en la evaluación de la biodiversidad dentro de los modelos de agricultura familiar.[EN] The Farm-Household models have been used to analyze ex-ante different policies; however, the state of the art is unknown in relation to the evaluation of biodiversity within these models. For this reason, a systematic review on Farm-Household models that integrate the “biodiversity” variable is required. For this purpose, we consulted a specialized search engine, applying a generic search strategy, which identified 1420 articles, of which only 23 were selected based on specific inclusion criteria. There is a gap in the evaluation of biodiversity within Farm-Household models.Los autores agradecen al Convenio de Subvención N.° 200-2015-FONDECYT, que en su cláusula tercera otorga a favor de la Universidad Nacional Agraria La Molina una subvención para el desarrollo del Doctorado de Economía de los Recursos Naturales y desarrollo sustentableReyes-Mandujano, IF.; Fernández, FJ.; Mercado, W.; Goméz, L.; Ponce, RD. (2020). Revisión Sistemática: análisis de la biodiversidad en las economías rurales mediante el modelo de hogares agrícolas y recomendaciones para futuros reportes. Economía Agraria y Recursos Naturales - Agricultural and Resource Economics. 20(1):53-75. https://doi.org/10.7201/earn.2020.01.03OJS537520

Desgaste por abrasión del acero api 5l x65 revestido con niobio por aspersión térmica a plasma y con inconel 625 por soldadura

El objetivo de este trabajo fue evaluar y caracterizar el comportamiento mecánico en desgaste del acero API 5L X65, revestido con niobio en comparación al desempeño del revestimiento de la aleación de inconel 625 empleados en la industria de petróleo y gas. El revestimiento de niobio fue obtenido por el proceso de aspersión térmica a plasma de arco no transferido y el revestimiento inconel 625 por soldadura con electrodo revestido. La resistencia al desgaste por abrasión fue evaluada según la norma Petrobras N-2567, en un tribómetro CTER, la rugosidad y el volumen de material desgastado se determinó a través de perfilometría y la dureza de los revestimientos por microscopia Vickers. Los revestimientos obtenidos fueron caracterizados respecto a su morfología por microscopia electrónica de barrido (MEB) y microscopía óptica (MO). La dureza del revestimiento de niobio obtenido puede haber contribuido a reducir la tasa de desgaste en comparación con el revestimiento de inconel 625

An integrative taxonomic approach reveals Octopus insularis as the dominant species in the Veracruz Reef System (southwestern Gulf of Mexico)

The common octopus of the Veracruz Reef System (VRS, southwestern Gulf of Mexico) has historically been considered as Octopus vulgaris, and yet, to date, no study including both morphological and genetic data has tested that assumption. To assess this matter, 52 octopuses were sampled in different reefs within the VRS to determine the taxonomic identity of this commercially valuable species using an integrative taxonomic approach through both morphological and genetic analyses. Morphological and genetic data confirmed that the common octopus of the VRS is not O. vulgaris and determined that it is, in fact, the recently described O. insularis. Morphological measurements, counts, indices, and other characteristics such as specific colour patterns, closely matched what had been reported for O. insularis in Brazil. In addition, sequences from cytochrome oxidase I (COI) and 16S ribosomal RNA (r16S) mitochondrial genes confirmed that the common octopus from the VRS is in the same highly supported clade as O. insularis from Brazil. Genetic distances of both mitochondrial genes as well as of cytochrome oxidase subunit III (COIII) and novel nuclear rhodopsin sequences for the species, also confirmed this finding (0–0.8%). We discuss our findings in the light of the recent reports of octopus species misidentifications involving the members of the ‘O. vulgaris species complex’ and underscore the need for more morphological studies regarding this group to properly address the management of these commercially valuable and similar taxa

Potential of Core-Collapse Supernova Neutrino Detection at JUNO

JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve

Detection of the Diffuse Supernova Neutrino Background with JUNO

As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO

Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30$M_{\odot}$ for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure

Red de sensores inalámbricos para el cuidado de la salud

La presente tesis presenta una propuesta de solución al problema de la carencia de los centros poblados para la medida y el análisis de signos vitales del poblador ubicado en una zona rural. Esta propuesta se implementó en el poblado de Tornamesa, perteneciente al distrito de San Bartolomé, provincia de Huarochirí, departamento de Lima. La propuesta fue validada por los datos obtenidos de la muestra de pobladores. De los diversos signos vitales se escogió la presión arterial y el pulso. El procedimiento para los otros signos vitales será igual; diferenciándose por el sensor o equipo a utilizarse. Para dar solución al problema se planteo una red y la medida de la presión arterial y del pulso de los pobladores. El envío de los datos tomados se realizó usando las tecnologías de la información y comunicación (TICs), a otro lugar distante para el análisis y diagnóstico por parte de un especialista