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Multi-Messenger Physics With the Pierre Auger Observatory
No full textAn overview of the multi-messenger capabilities of the Pierre Auger Observatory is presented. The techniques and performance of searching for Ultra-High Energy neutrinos, photons and neutrons are described. Some of the most relevant results are reviewed, such as stringent upper bounds that were placed to a flux of diffuse cosmogenic neutrinos and photons, bounds placed on neutrinos emitted from compact binary mergers that were detected by LIGO and Virgo during their first and second observing runs, as well as searches for high energy photons and neutrons from the Galactic center that constrain the properties of the putative Galactic PeVatron, observed by the H.E.S.S. collaboration. The observation of directional correlations between ultra-high energy cosmic rays and either high energy astrophysical neutrinos or specific source populations, weighted by their electromagnetic radiation, are also discussed. They constitute additional multi-messenger approaches aimed at identifying the sources of high energy cosmic rays. © Copyright © 2019 Kampert, Alejandro Mostafa, Zas and The Pierre Auger Collaboration
Direct measurement of the muonic content of extensive air showers between 2× 1017 and 2×1018 eV at the Pierre Auger Observatory
No full textThe hybrid design of the Pierre Auger Observatory allows for the measurement of the properties of extensive air showers initiated by ultra-high energy cosmic rays with unprecedented precision. By using an array of prototype underground muon detectors, we have performed the first direct measurement, by the Auger Collaboration, of the muon content of air showers between 2 × 10 17 and 2 × 10 18 eV. We have studied the energy evolution of the attenuation-corrected muon density, and compared it to predictions from air shower simulations. The observed densities are found to be larger than those predicted by models. We quantify this discrepancy by combining the measurements from the muon detector with those from the Auger fluorescence detector at 1017.5eV and 1018eV. We find that, for the models to explain the data, an increase in the muon density of 38 % ± 4 % (12 %) ±18%21% for EPOS-LHC, and of 50 % (53 %) ± 4 % (13 %) ±20%23% for QGSJetII-04, is respectively needed. © 2020, The Author(s)
Transforming weaknesses into strengths through organisational shamans: The case of Colombian peace commissioner that signed the final agreement
No full textThe aim of this paper is to propose a tool for organisational management based on the analysis and interpretation of shamans in organisations, defining organisational shaman as someone who perceives, predicts and manages the company's social and environmental health. To achieve this goal, we follow a mixed sequential methodology, i.e., quantitative and qualitative, that begins with the revision of the current status of the discussion about organisational shamans through a bibliometric analysis, and ends with a content analysis that serves to propose a conceptual tool to search and select a shaman. Once define the conceptual tool, we verified it in the case of the Colombian Commissioner for Peace, one of the negotiators of the peace agreement signed between the government and the armed group FARC-EP. To finally, understand how it has been possible to transform one of the country's weaknesses into strength, and how the consultant-shaman is jointly responsible for the results. © 2021 Inderscience Enterprises Ltd
Prediction of noise from wind turbines: A theoretical and experimental study
No full textSeveral noise propagation models used to calculate the noise produced by wind turbines have been reported. However, these models do not accurately predict sound pressure levels. Most of them have been developed to estimate the noise produced by industries, in which wind speeds are less than 5 m/s, and conditions favor its spread. To date, very few models can be applied to evaluate the propagation of sound from wind turbines and most of these yield inaccurate results. This study presents a comparison between noise levels that were estimated using the prediction method established in ISO 9613 Part 2 and measured levels of noise from wind turbines that are part of a wind farm currently in operation. Differences of up to 56.5 dBZ, with a median of 29.6 dBZ, were found between the estimated sound pressure levels and measured levels. The residual sound pressure levels given by standard ISO 9613 Part 2 for the wind turbines is larger for high frequencies than those for low frequencies. When the wide band equivalent continuous sound pressure level is expressed in dBA, the residual varies between -4.4 dBA and 37.7 dBA, with a median of 20.5 dBA. © 2019 Revista Facultad de Ingenieria.Hay muchos modelos de propagación de ruido que se utilizan para calcular el ruido proveniente de los aerogeneradores. Sin embargo, fallan en la precisión con que pueden predecir los niveles de presión sonora. La mayoría de estos modelos han sido desarrollados para estimar el ruido proveniente de las industrias, con velocidades del viento inferiores a 5 m/s y condiciones favorables a su propagación. Hasta ahora hay muy pocos modelos que se puedan aplicar para la propagación del sonido proveniente de los aerogeneradores y la mayoría de ellos arrojan resultados poco precisos. En este artículo se presenta una comparación entre los niveles de ruido estimados a través del método de predicción establecido en la norma ISO 9613 Parte 2 y los niveles de ruido medidos proveniente de los aerogeneradores instalados en un parque eólico en funcionamiento. Se encontraron diferencias entre los niveles de presión sonora estimados y medidos de hasta 56.5 dBZ, con una mediana de 29.6 dBZ. El nivel de presión sonora residual arrojado por la norma ISO 9613 Parte 2 para los aerogeneradores es mayor para las frecuencias altas que para las frecuencias bajas. © 2019 Revista Facultad de Ingenieria
Mechanical and Hydraulic Behaviour of Unsaturated Residual Soils
No full textThe negative effect of rains on the stability of the slopes is a problem that, added to anthropic factors and population settlements, currently generate not only material but also human losses. Therefore, the evaluation of threat by mass movements has become a first order problem. However, one of the aspects that presents the greatest uncertainty in these evaluations is the effect of soil saturation. This paper presents a methodology for evaluating the effect of rainfall by estimating the probability of soil saturation using the Richards equation and the first order and second moment method-FOSM. The methodology was applied considering two residual soils from the area of north-western Colombia named Aburra valley. For this purpose, a characterization of each material was made, evaluating the variability of shear strength parameters and hydraulic parameters. Subsequently, infiltration models were made using the Richards equation with a historical rain event that occurred between October 27 and November 13, 2010, which exceeded the failure thresholds established for the Aburra Valley and generated several landslides. The advance of the wetting front was evaluated, and the probability of saturation was determined. It was found that, in all the evaluated soils, full saturation reaches depths between 600 and 6000 mm and the probability of saturation is greater in soils from Stock de Altavista that report a lesser values of air entry suction. The mean values of φ b varies between 1.3° and 6.5° for soils from Stock de Altavista. © Published under licence by IOP Publishing Ltd
Health-related quality of life, anxiety, depression and spiritual wellbeing in patients with chronic obstructive pulmonary disease [Calidad de vida relacionada con la salud, ansiedad, depresión y bienestar espiritual en pacientes con diagnóstico de enfermedad pulmonar obstructiva cronica]
No full textThe aim of this study was to evaluate the relationship between health-related quality of life -HRQOL, anxiety, depression and spiritual well-being in patients diagnosed with chronic obstructive pulmonary disease -COPD. The sample consisted of 71 patients with a mean age of 72 years old. The study design was descriptive correlational. Instruments: Medical Outcomes Study 36-Item ShortForm Health Survey, MOS SF-36, Airways Questionnaire (AQ-20), Spirituality Index of Well-Being (SIWB) and The Hospital Anxiety and Depression Scale -HADS. Results: The physical-quality-of-life index of MOS-SF36 had a lower score with respect to the mental summary index, at a general level the HRQoL of these patients was favorable. Regarding multiple linear regression analysis, there was a negative relationship of anxiety with quality of life measured with AQ-20. The results confirm the weight of negative emotions on the perception of quality of life of patients with COPD. © 2018 Fundación AIGLé.El propósito de este estudio fue evaluar las relaciones entre calidad de vida relacionada con la salud -CVRS, la ansiedad, la depresión y el bienestar espiritual en pacientes con diagnóstico de enfermedad pulmonar obstructiva crónica -EPOC. La muestra estuvo conformada por 71 pacientes con una media de edad de 72 años. El diseño del estudio fue descriptivo correlacional. Instrumentos: cuestionario de calidad de vida relacionada con la salud -MOS SF36, cuestionario de calidad de vida abreviado para pacientes con EPOC Airways -AQ20, inventario de bienestar espiritual -SIWB y escala hospitalaria de ansiedad y depresión -HADS. Resultados: el índice sumario físico de calidad de vida del MOS-SF36 tuvo una puntación más baja con respecto al índice de sumario mental, a nivel general la CVRS de estos pacientes fue favorable. Respecto al análisis de regresión lineal múltiple, hubo una relación negativa de la ansiedad con la calidad de vida medida con el AQ-20. Los resultados encontrados confirman el peso de la ansiedad, especialmente, sobre la percepción de la CVRS en los pacientes con EPOC. © 2018 Fundación AIGLé
Emotional Networked maps from EEG signals
No full textThe EEG has showed that contains relevant information about recognition of emotional states. It is important to analyze the EEG signals to understand the emotional states not only from a time series approach but also determining the importance of the generating process of these signals, the location of electrodes and the relationship between the EEG signals. From the EEG signals of each emotional state, a functional connectivity measurement was used to construct adjacency matrices: lagged phase synchronization (LPS), averaging adjacency matrices we built a prototype network for each emotion. Based on these networks, we extracted a set node features seeking to understand their behavior and the relationship between them. We found through the strength and degree, the group of representative electrodes for each emotional state, finding differences from intensity of measurement and the spatial location of these electrodes. In addition, analyzing the cluster coefficient, degree, and strength, we find differences between the networks from the spatial patterns associated with the electrodes with the highest coefficient. This analysis can also gain evidence from the connectivity elements shared between emotional states, allowing to cluster emotions and concluding about the relationship of emotions from EEG perspective. © 2020 IEEE
Priorities and interactions of Sustainable Development Goals (SDGs) with focus on wetlands
No full textWetlands are often vital physical and social components of a country's natural capital, as well as providers of ecosystem services to local and national communities. We performed a network analysis to prioritize Sustainable Development Goal (SDG) targets for sustainable development in iconic wetlands and wetlandscapes around the world. The analysis was based on the information and perceptions on 45 wetlandscapes worldwide by 49 wetland researchers of the GlobalWetland Ecohydrological Network (GWEN). We identified three 2030 Agenda targets of high priority across the wetlandscapes needed to achieve sustainable development: Target 6.3-"Improve water quality"; 2.4-"Sustainable food production"; and 12.2-"Sustainable management of resources". Moreover, we found specific feedback mechanisms and synergies between SDG targets in the context of wetlands. The most consistent reinforcing interactions were the influence of Target 12.2 on 8.4-"Efficient resource consumption"; and that of Target 6.3 on 12.2. The wetlandscapes could be differentiated in four bundles of distinctive priority SDG-targets: "Basic human needs", "Sustainable tourism", "Environmental impact in urban wetlands", and "Improving and conserving environment". In general, we find that the SDG groups, targets, and interactions stress that maintaining good water quality and a "wise use" of wetlandscapes are vital to attaining sustainable development within these sensitive ecosystems. © 2019 by the authors
Nonlinear optical properties of n-type asymmetric double δ -doped quantum wells: role of high-frequency laser radiation, doping concentration and well width
No full textA numerical investigation on the nonlinear optical rectification, second and third harmonic generation coefficients in asymmetric double n-type δ-doped GaAs quantum well is performed in order to identify the influence of non-resonant intense laser radiation, doping concentration and the change in well widths. The energy eigenvalues and the corresponding eigenfunctions are determined by using effective-mass and parabolic band approximations. The working analytical expressions for the optical coefficients are derived from the iterative solving of compact-density matrix description of dielectric susceptibility. The obtained results reveal that the position and amplitude of the nonlinear optical rectification, second and third harmonic generation coefficients can be altered by modifying the external field as well as the compositional and geometrical setups. © 2020, Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature
Challenge-based learning: A ‘entrepreneurship-oriented’ teaching experience
No full textChallenge-based Learning (CBL) is a pedagogical approach that actively involves students in a realistic, problematic and meaningful situation related to their environment, which requires defining a challenge and implementing a solution for it (OIETM, 2015). The CBL methodology was applied by instructors with the support of students, part of the management programme from a Colombian university. The goal was to assess the validity of the methodology and examine solutions proposed by students to real-life problems in organisations. After assessing the challenge-based learning (CBL) it can be concluded, that a link to the entrepreneurial orientation exists. This link promotes the development of critical and constructive thinking, while encouraging students to analyse, design, develop and execute solutions for real-life problems, similar to those they will encounter as graduate students in any organisation. © 2020 British Educational Leadership, Management & Administration Society (BELMAS)