Microproject-based teaching/learning methodology focused on emerging technologies and international entities cooperation

[EN] : This paper deals with the implementation of an educational methodology based on microprojects into the subject ‘Manufacturing Technology’ of the EHEA (European Space of Higher Education) engineering degrees. The main idea is to consolidate the theoretical background by working on microprojects ordered by foreign entities. Under this approachstudents implement the theoretical knowledge acquired in the classroom facing real world problems, such as scope definition, planning and team work, while promoting the use of English and information and communication technologies (ICTs). Results show higher motivation and level of interest among students as well as an improvement on their scores when compared with traditional teaching/learning methods.Fernández-Ceniceros, J.; Sanz-García, A.; Antoñanzas-Torres, F.; Alía-Martínez, M.; Pernía-Espinoza, A. (2015). Microproject-based teaching/learning methodology focused on emerging technologies and international entities cooperation. En 1ST INTERNATIONAL CONFERENCE ON HIGHER EDUCATION ADVANCES (HEAD' 15). Editorial Universitat Politècnica de València. 311-318. https://doi.org/10.4995/HEAd15.2015.336OCS31131

Ice nucleating particles carried from below a phytoplankton bloom to the arctic atmosphere

Author Posting. © American Geophysical Union, 2019. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 46(14), (2019): 8572-8581, doi: 10.1029/2019GL083039.As Arctic temperatures rise at twice the global rate, sea ice is diminishing more quickly than models can predict. Processes that dictate Arctic cloud formation and impacts on the atmospheric energy budget are poorly understood, yet crucial for evaluating the rapidly changing Arctic. In parallel, warmer temperatures afford conditions favorable for productivity of microorganisms that can effectively serve as ice nucleating particles (INPs). Yet the sources of marine biologically derived INPs remain largely unknown due to limited observations. Here we show, for the first time, how biologically derived INPs were likely transported hundreds of kilometers from deep Bering Strait waters and upwelled to the Arctic Ocean surface to become airborne, a process dependent upon a summertime phytoplankton bloom, bacterial respiration, ocean dynamics, and wind‐driven mixing. Given projected enhancement in marine productivity, combined oceanic and atmospheric transport mechanisms may play a crucial role in provision of INPs from blooms to the Arctic atmosphere.We sincerely thank the U.S. Coast Guard and crew of the Healy for assistance with equipment installation and guidance, operation of the underway and CTD systems, and general operation of the vessel during transit and at targeted sampling stations. We would also like to thank Allan Bertram, Meng Si, Victoria Irish, and Benjamin Murray for providing INP data from their previous studies. J. M. C., R. P., P. L., L. T., and E. B. were funded by the National Oceanic and Atmospheric Administration (NOAA)’s Arctic Research Program. J. C. was supported by the NOAA Experiential Research & Training Opportunities (NERTO) program. T. A. and N. C. were supported through the NOAA Earnest F. Hollings Scholarship program. A. P. was funded by the National Science Foundation under Grant PLR‐1303617. Russel C. Schnell and Michael Spall are acknowledged for insightful discussions during data analysis and interpretation. There are no financial conflicts of interest for any author. INP data are available in the supporting information, while remaining DBO‐NCIS data presented in the manuscript are available online (at https://www2.whoi.edu/site/dboncis/).2020-01-1

Don Lupe Oro C2020: nueva variedad de trigo duro para el noroeste de México

El noroeste de México es la principal región productora de trigo cristalino (Triticum durum Desf.). Durante el año 2020 se cultivaron 159,229 ha con este tipo de trigo, las cuales representaron el 90.5 % de la superficie total sembrada en México. Dicha región alcanzó una producción de 1.19 millones de toneladas, con un valor de la producción de 5.25 mil millones de pesos (SIAP, 2021)

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

MESACS: A Multi-Method Environmental Study over The Arctic Chukchi Sea

The Arctic environment is a dynamic part of Earth’s natural system and is currently undergoing rapid increasing air temperature and decreasing sea ice extent, leading to more open ocean waters. As open water areas become more prevalent, phytoplankton communities near the surface of the ocean can proliferate earlier in the year and are apt to reach higher concentrations by the end of the summer season. Phytoplankton biomass around the world has been known to produce a microscopic biofilm at the surface of the ocean composed of biogenic and biological particles which then become airborne and work as both cloud condensation nuclei and ice nucleating particles. These nuclei can subsequently impact the physical and radiative properties of clouds, thereby affecting the surface energy budget. Various studies have investigated the possible link between phytoplankton biomass and cloud condensation nuclei, but the distinct link between ice nucleating particles and the ocean has only rarely been explored, even more so in the high latitude Arctic environment. A comprehensive multi-method study was executed to investigate marine aerosols originating from surface of the ocean and their role as ice nucleating particles in Arctic clouds over the Chukchi Sea. The overarching objective was to participate in a field study, in parallel with supporting lab and remote sensing techniques. The field study named Ice Nucleating over the ARCtic (INARCO II) provided excellent research experience for a graduate student to make local in situ measurements of both Arctic air and seawater. This study also explores for the first time how microscopic haloarchaeal species Haloferax sulfurifontis, Natronomonas pharaonsis, Haloquadratum walsbyi, and Halococcus morrhuae perform as ice nucleating particles. All four species have demonstrated some form of ice nucleating ability by nucleating ice at temperatures above homogeneous freezing T≤~-38℃. The third study, remote sensing analysis, quantifiably characterized the Chukchi Sea phytoplankton biomass using satellite derived chlorophyll-a measurements as a tracer for phytoplankton biomass and its correlation to key cloud physical properties including ice cloud effective radius (re), ice water path (IWP), cloud-top height (CTH), cloud-top temperature (CTT), cloud top pressure (CTP), phase, and cloud fraction at varying 1-km or 5-km spatial resolution. Correlation results and scatter plot linear fitting indicate a positive correlation between Chl-a concentrations with ice cloud effective radius (P-value = 0.0013 and R-value = 0.45) and cloud pressure (P = 0.0009, R = 0.46). Negative correlations were found between Chl-a with cirrus cloud reflectance (P = 0.0013, R = -0.45) and ice cloud optical thickness (P = 0.0267, R = -0.32). Spatial analysis results have shown that Chl-a concentrations do not increase evenly in exceptionally high months, but instead increase along the terrestrial coastlines with a weakening gradient leading to near zero concentrations in open ocean. Mean summer Chl-a concentrations for the entire Chukchi Sea showed a variable year to year summer season with a small increasing trend. Additionally, mean summer Chl-a concentrations were maintained between 1.4 mg/m3 and 2.1 mg/m3 in the past 15 years. Together this multi-method investigation produced results exemplifying the importance of considering Arctic plankton biomass and other biogenic INPs in future climatic models since changes in the sea surface concentrations appear to significantly influence certain Arctic cloud properties

Numerical-Informational methodology for characterising steel bolted components coupling finite element simulations and soft computing techniques

La caracterización de uniones de acero ha sido un tema de investigación muy activo en las últimas décadas debido a su complejidad y vital importancia en el comportamiento de una estructura. La aparición del concepto semirrígido proporcionó destacados beneficios tanto desde el punto de vista estructural como de la perspectiva económica pero, a su vez, exigió procedimientos de cálculo más sofisticados y avanzados. Un enfoque que ha ganado popularidad entre investigadores y calculistas es el método basado en componentes, capaz de estimar el comportamiento de una unión estructural a partir de las curvas características fuerza-desplazamiento de cada uno de los componentes de la unión. Aunque el método es muy versátil y permite modelar cualquier configuración de unión, es necesaria una detallada caracterización de cada uno de los componentes para conseguir una buena precisión en el cálculo. En este contexto, esta tesis presenta una metodología híbrida para determinar la curva completa fuerza-desplazamiento en componentes atornillados. La metodología combina modelos numéricos y modelos de predicción para estimar parámetros de las curvas, tales como la rigidez inicial, la resistencia máxima o el desplazamiento en la fractura. En primer lugar se desarrollan modelos numéricos basados en el método de los elementos finitos (FEM) para reproducir la respuesta real del componente atornillado. Estos modelos incorporan mecanismos de daño progresivo y criterios de fallo para estimar el desplazamiento en la fractura. Con el objetivo de minimizar el gran coste computacional del FEM, se genera un conjunto de simulaciones para entrenar modelos de predicción basados en soft computing (SC). Estos modelos de predicción incluyen una optimización con algoritmos genéticos (GA) para ajustar los parámetros del modelo y, al mismo tiempo, seleccionar las variables de entrada más importantes en la predicción de la respuesta fuerza-desplazamiento. En su conjunto, la metodología propuesta es capaz de proporcionar modelos de predicción precisos y parsimoniosos. La aplicación de la metodología híbrida queda demostrada en la caracterización de dos componentes atornillados fundamentales: la unión a solape y la unión en 'T'. Los resultados obtenidos en la caracterización de ambos componentes resaltan la mayor precisión de la metodología propuesta en comparación con las actuales normativas de cálculo y con modelos analíticos tradicionales. Una vez entrenados y validados, los modelos de predicción son capaces de reemplazar a las costosas simulaciones FE sin una pérdida de precisión significativa y con un coste computacional despreciable. Por tanto, la metodología híbrida podría representar una herramienta efectiva para ser implementada en programas de análisis estructural para diseñadores y calculistas. Finalmente, las contribuciones presentadas en estas tesis evidencian el gran potencial de combinar FEM y SC para predecir el comportamiento de componentes estructurales.Over the last few decades, the characterisation of steel joints has been a highly active research topic thanks to its inherent complexity and utmost importance in the behaviour of a whole structure. The emergence of the semi-rigid concept provided significant benefits from both the structural and economic perspectives, in exchange for more advanced and sophisticated calculation procedures. An approach that has gained popularity is the component-based method, in which the overall behaviour of the joint can be determined from the force-displacement responses of its individual components. Although this method is very versatile for modelling any joint configuration, a detailed characterisation of components is necessary to ensure accuracy. In this context, this thesis presents a hybrid methodology to determine the comprehensive force-displacement curve of bolted components: from initial stiffness up to the fracture point. This methodology couples numerical and informational models to predict key parameters of curves, such as initial stiffness, maximum resistance and displacement at failure. To this end, numerical models based on the finite element method (FEM) are first developed to reproduce the real response of bolted components. These models incorporate progressive damage mechanisms and failure criteria to accurately estimate the displacement at fracture. In order to minimise the computational burden of the FEM, the results of a set of simulations are then utilised to train informational models based on soft computing (SC). A genetic algorithm (GA) optimisation is included to set up model parameters and select the most relevant input variables for predicting the force-displacement response. Taken together, the proposed methodology is capable of providing accurate and parsimonious informational models. The applicability of the hybrid methodology is demonstrated for the characterisation of two fundamental bolted components: the lap and the T-stub. The results obtained highlight the superior accuracy of this methodology as compared to current regulatory codes and traditional analytical models. Once trained and validated, the informational models are able to replace costly FE simulations without a significant decrease in accuracy, and at a negligible computational cost. Therefore, the hybrid methodology could represent an effective tool to be implemented in structural analysis software for designers and practitioners. Overall, the contributions presented in this thesis provide evidence of the great potential of combining FEM and SC to predict the behaviour of structural components

Reseña a: “Sistemas, Cambio y Caos” De la obra de Arias y Heredia, y Reflexiones para el Diseño de Modelos de Pronóstico

En este trabajo se resumen las aportaciones de Arias y Heredia, sobre los sistemas, cambio y caos que en lo sucesivo servirán de base al autor en la reflexión en forma complementaria sobre la actividad generadora de pronósticos como parte central del proceso de planeación de las organizaciones, principalmente las de tipo comercial.Modelos, Sistemas, Análisis de Regresión

LA VARIABLE DE SEGMENTACIÓN DE COMPORTAMIENTO A TRAVÉS DEL CRITERIO DE COMPRA Y SU RELACIÓN CON EL GÉNERO DEL COMPRADOR

En el presente trabajo se trata de probar la relación existente entre el género del comprador de productos básicos; cárnicos y aceites comestibles, y el criterio de compra expresada bajo la dicotomía: Precio del producto vs. Diferenciación del mismo. Indagación realizada durante el año 2008, en la ciudad de Culiacán, Sinaloa México, a través de una de muestra de 310 compradores, en donde se presentan los resultados en forma concluyente; no existe una relación significativa a un nivel a=0.05, entre la variable demográfica de segmentación basada en el sexo del comprador con relación a la variable de segmentación por comportamiento de compra.Diferenciación de Productos, Variable de Segmentación, Productos Básicos