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Resumen Otto (2016) es el primer huracán en la historia documentada de ciclones tropicales de haber alcanzado directamente Costa Rica. Este trabajo analiza las descargas eléctricas (DE) de Otto en noviembre 2016 en su paso desde el Caribe hasta el Pacífico, usando datos de la World Wide Lightning Location Network; lo cual constituye una investigación pionera en esta región de Centroamérica. Las DE asociadas a Otto capturan muy bien las fases de intensificación y degradación de este huracán, que como variable podría ser parametrizada en los modelos numéricos para mejorar el entendimiento y evolución de estos sistemas. Otto presentó tres picos máximos de descargas; uno en categoría 1 en la escala Saffir-Simpson, otro en categoría 2 y el último en la categoría 3 (OH3), poco antes de su entrada a tierra entre Costa Rica y Nicaragua. La región de mayor cantidad de DE se desplazó del centro hacia las zonas más externas del huracán conforme éste se intensificó. En el caso de OH3, el máximo de DE se ubicó en las bandas externas de Otto (250-300 km). Durante su evolución, las de máximas DE observadas estaban relacionadas con temperaturas del tope de las nubes menores a los -70 °C.

The concept of Sustainable Development has given rise to multiple interpretations. In this article, it is proposed that Sustainable Development should be interpreted as the capacity of territory, community, or landscape to conserve the notion of well-being that its population has agreed upon. To see the implications of this interpretation, a Brander and Taylor model, to evaluate the implications that extractivist policies have over an isolated community and cooperating communities, is proposed. For an isolated community and through a bifurcation analysis in which the Hopf bifurcation and the heteroclinic cycle bifurcation are detected, 4 prospective scenarios are found, but only one is sustainable under different extraction policies. In the case of cooperation, the exchange between communities is considered by coupling two models such as the one defined for the isolated community, with the condition that their transfers of renewable resources involve conservation policies. Since human decisions do not occur in a continuum, but rather through jumps, the mathematical model of cooperation used is a Filippov System, in which the dynamics could involve two switching manifolds of codimension one and one switching manifold of codimension two. The exchange in the cooperation model, for specific parameter arrangements, exhibits n-periodic orbits and chaos. It is notable that, in the cases in which the system shows sliding, it could be interpreted as a recovery delay related to the time needed by the deficit community to recover, until its dependence on the other community stops. It is concluded (1) that a sustainability analysis depends on the way well-being is defined because every definition of well-being is not necessarily sustainable, (2) that sustainability can be visualized as invariant sets in the nonzero region of the space of states (equilibrium points, n-periodic orbits, and strange attractors), and (3) that exchange is key to the prevalence of the human being in time. The results question us on whether Sustainable Development is only to keep us alive or if it also implies doing it with dignity.

Lightning activity has been recognized to have, historically, social and environmental consequences around the globe. This work analyzes the space-time distribution of lightning-densities (D) in an extended Central America region (ECA). World Wide Lightning Location Network data was analyzed to link D with dominant climate patterns over the ECA for 2012–2020. D associated with cold surges entering the tropics dominate during boreal winter. The highest D (hot-spots) was found to agree well with previously known sites, such as the “Catatumbo” in Venezuela; however, D was lower here due to different detection efficiencies. Previously reported hot-spots showed strong continental signals in CA; however, in this work, they were over the oceans near to coastlines, especially in the eastern tropical Pacific (ETP). Most cold-spots, implying a minimum of vulnerability to human impacts and to some industries, were situated in the Caribbean Sea side of Central America. The Mid-Summer-Drought and the Caribbean-Low-Level-Jet (CLLJ) markedly reduced the D during July-August. The CLLJ in the central CS and across the Yucatan and the southern Gulf of Mexico acts as a lid inhibiting convection due to its strong vertical shear during the boreal summer. The CLLJ vertical wind-shear and its extension to the Gulf of Papagayo also diminished convection and considerably decreased the D over a region extending westward into the ETP for at least 400–450 km. A simple physical mechanism to account for the coupling between the CLLJ, the MSD, and lightning activity is proposed for the latter region.

Hurricane Otto (2016) was characterised by remarkable meteorological features of relevance for the scientific community and society. Scientifically, among the most important attributes of Otto is that it underwent a rapid intensification (RI) process. For society, this cyclone severely impacted Costa Rica and Nicaragua, leaving enormous economic losses and many fatalities. In this study, a set of three numerical simulations are performed to examine the skill of model estimations in reproducing RI and trajectory of Hurricane Otto by comparing the results of a global model to a regional model using three different planetary boundary layer parameterizations (PBL). The objective is to set the basis for future studies that analyse the physical reasons why a particular simulation (associated with a certain model setup) performs better than others in terms of reproducing RI and trajectory. We use the regional model Weather Research and Forecasting—Advanced Research WRF (WRF-ARW) with boundary and initial conditions provided by the Global Forecast System (GFS) analysis (horizontal resolution of 0.5 degrees). The PBL used are the Medium Range Forecast, the Mellor-Yamada-Janjic (MYJ), and the Yonsei University (YSU) parameterizations. The regional model is run in three static domains with horizontal grid spacing of 27, 9 and 3 km, the latter covering the spacial extent of Otto during the simulation period. WRF-ARW results improve the GFS forecast, in almost every aspect evaluated in this study, particularly, the simulated trajectories in WRF-ARW show a better representation of the cyclone path and movement compared to GFS. Even though the MYJ experiment was the only one that exhibited an abrupt 24-h change in the storm’s surface wind, close to the 25-knot threshold, the YSU scheme presented the fastest intensification, closest to reality.

The evaluation of intraseasonal, seasonal, and annual variability of rainfall and temperature extremes, while using climate change scenarios data, is extremely important for socio-economic activities, such as water resources management. Costa Rica, a climate change hotspot, is largely dependent on rainfall for socioeconomic activities; hence, the relevance of this study. Based on the NEX-GDDP, rainfall and temperature range were analyzed for Costa Rica at the end of the century (2070–2099), while using 1970–1999 as a baseline for six available meteorological stations. Differences between the multimodel ensembles of two prospective scenarios (RCP 4.5 and 8.5) and the historical information were computed. This study highlights Costa Rica as an inflexion region for climate change impacts in Central America, for which projected scenarios suggest an early onset of the rainy season, and a decline in the mid-summer drought (MSD) minimum. The assessment of model data in some regions of Costa Rica, for which historical data were available, suggests that the latter does not capture a well-known regional climate feature, the MSD, in both precipitation and temperature range well. The availability of observed past data sources is a major limitation of this research; however, with the station data used, it is still possible to draw some conclusions regarding future climate in some regions of Costa Rica, especially in the northwest side of the country, where past data are consistent with model information, providing a more reliable picture of changes in climate there that has potential implications for socioeconomic sectors.

Surface and upper air observations and MM5v3 simulations examined the structure and inland penetration of sea breeze (SB) along the Grande de Tárcoles river basin (GTRB), central Pacific, Costa Rica, for two different intensity regimes of the Caribbean Low-Level Jet (CLLJ). Data comprise the period of 1 July to 16 September 2004 from Ticosonde-North American Monsoon Experiment, and a local University of Costa Rica-National Meteorological Institute field campaign. Maximum precipitation occurs between 14:00–17:00 LST, showing a time lag of 2 to 3 h after the temperature maximum, suggesting that local diurnal heating is key to convection. July–August precipitation exhibited a rainfall decrease along GTRB due to the SB dynamical processes interaction with a strong CLLJ. The SB maximum inland incursion was 24 km, with no evidence of its penetration into the Central Valley. The MM5v3 simulations for two convective and boundary layer (BL) schemes captured some SB structure features along the GTRB. Comparison of model results with observed data shows deficiencies in the model representation of the surface flow near coastal regions. Differences may be the result of time lag model’s poor responses to actual early morning BL sea–land temperature gradients. MM5v3 configurations used in this study resulted in biased wind speed simulations.

A theoretical study of the effect of the substituent Z on the gas phase acidity of substituted benzoic acids ZC6H4COOH in terms of density functional theory descriptors (chemical potential, softness and Fukui function) is presented. The calculated gas phase ΔacidG° values obtained were close to the experimental ones reported in the literature. The good relationship between the ΔacidG° values and the electronegativity of ZC6H4COOH and its fragments, suggested a better importance of the inductive than polarizability contributions. The balance of inductive and resonance contributions of the substituent in the acidity of substituted benzoic acids showed that the highest inductive and resonance effects were for the -SO2CF3 and -NH2 substituents in the para- and ortho-position, respectively. The Fukui function confirmed that the electron-releasing substituent attached to the phenyl ring of benzoic acid decreased the acidity in the trend ortho > meta > para, and the electron-withdrawing substituent increased the acidity in the trend ortho < meta < para.

In the first part of this work it was determined that general circulation model (GCM) ECHAM4.5 shows more ability than CCM3.6 to simulate key climate features of Central America. For such reason, output from ECHAM4.5 was used to perform a dynamical downscaling experiment using the regional model MM5v3, in which a set of high-resolution simulations (of up to 30-km horizontal resolution) was generated for January 2000. The results of the dynamical downscaling allow to conclude that MM5v3 is able to suitably reproduce aspects of the Central American climate that GCMs cannot capture because of their coarse horizontal resolution, their limitations in representing both the regional topography and the mesoscale dynamical interactions. Comparison with data derived from observations indicates that the MM5v3 simulates the region of maximum low-level wind that is related to the Intra-Americas Seas Low Level Jet, although the regional model underestimates its intensity. Regarding the precipitation patterns, they agree with those derived from the observations (drier areas in the Pacific, wetter areas in the Caribbean). Nevertheless, there is a generalized overestimation in the amount of simulated rain. The analysis of the standard deviation for a twelve-member sample shows areas in which MM5v3 has greater dispersion or uncertainty (mainly to the south of Panama). Keywords: numerical models, seasonal climate prediction, dynamical downscaling, climate, climate variability.

Este estudio analiza los elementos descritos e implementados en el modelo de Educación Intercultural Bilingüe en Honduras, que tiene como resultado tácito la revitalización de la lengua pech¹. Se empleó una metodología cualitativa, apoyada por una investigación documental a través del método de análisis documental y la recopilación, procesamiento e interpretación de estadísticas educativas. Previo a esto, se realizó la investigación documental, donde se tomaron como muestra los documentos obtenidos en el proceso de recolección de datos. Luego, se aplicaron entrevistas estructuradas a la totalidad de las personas informantes (16 en total); también entrevistas a profundidad al personal directivo, docente, padres y madres de familia, y personas líderes comunitarias. Los datos cualitativos se procesaron a través de la transcripción de los audios y se triangularon los resultados de las entrevistas, los resultados de la investigación documental y la teoría. Los resultados principales muestran el quebrantamiento de la transmisión intergeneracional de la lengua pech. La población hablante representa el 4.19 % 1 de los 2,122 que habitan en el núcleo indígena donde se realizó este estudio. De manera paulatina, la lengua pech ha sido desplazada por la lengua oficial, el español, tanto en el hogar como en la escuela, el trabajo y la vida pública. Existen materiales educativos, pero son insuficientes para la enseñanza de la lectoescritura del pech, tomando en cuenta que en el Currículo Nacional Básico es considerada como segunda lengua. El modelo de educación intercultural bilingüe, que tiene como función primordial revitalizar la lengua pech e iniciar un proceso de alfabetización para la población, no logra su cometido. El valor cultural que tiene la lengua para los pech es símbolo identitario que agencia un potencial para su revitalización.

Este artículo tiene como objetivo determinar cuáles son los factores que inciden en la reintegración económica de excombatientes de grupos insurgentes en el departamento de Bolívar, Colombia. Para esto, se analizaron algunas variables socioeconómicas como la edad, el nivel educativo, el género, el estado conyugal, la descendencia, los ingresos familiares, el ex grupo armado y el tipo de desmovilización del individuo. Metodológicamente, se aplicó un modelo econométrico de selección binaria. Entre las conclusiones principales de este artículo, se destaca que los determinantes de reintegración económica en el departamento de Bolívar son el nivel educativo, el género y los ingresos familiares de los excombatientes.

Due to the complex interplay of various meteorological phenomena, simulating weather is a challenging and open research problem. In this contribution, we propose a novel physics-based model that enables simulating weather at interactive rates. By considering atmosphere and pedosphere we can define the hydrologic cycle - and consequently weather - in unprecedented detail. Specifically, our model captures different warm and cold clouds, such as mammatus, hole-punch, multi-layer, and cumulonimbus clouds as well as their dynamic transitions. We also model different precipitation types, such as rain, snow, and graupel by introducing a comprehensive microphysics scheme. The Wegener-Bergeron-Findeisen process is incorporated into our Kessler-type microphysics formulation covering ice crystal growth occurring in mixed-phase clouds. Moreover, we model the water run-off from the ground surface, the infiltration into the soil, and its subsequent evaporation back to the atmosphere. We account for daily temperature changes, as well as heat transfer between pedosphere and atmosphere leading to a complex feedback loop. Our framework enables us to interactively explore various complex weather phenomena. Our results are assessed visually and validated by simulating weatherscapes for various setups covering different precipitation events and environments, by showcasing the hydrologic cycle, and by reproducing common effects such as Foehn winds. We also provide quantitative evaluations creating high-precipitation cumulonimbus clouds by prescribing atmospheric conditions based on infrared satellite observations. With our model we can generate dynamic 3D scenes of weatherscapes with high visual fidelity and even nowcast real weather conditions as simulations by streaming weather data into our framework. [ABSTRACT FROM AUTHOR]

According to literature, there is a strong influence of stress with the emergence of diseases. In this paper the attributes that make possible this influence in order to develop a mathematical model that allows the approach of scenarios that change with the frequency an individual implements temporary solutions to deal with stress (pseudosolutions), or change the frequency with which it receives the specialized medical treatment to treat the disease were considered. Results are conclusive of the dynamic behavior of the system, allowing the configuration of different scenarios in which the individual: 1) is completely healed, 2) reaches stable levels of stress-sickness which can bear safely but with the implementation of different pseudosolutions and medical treatments, or 3) jeopardizes its life. [ABSTRACT FROM AUTHOR]

Por lo general, el profesorado se centra en promover la criticidad y trata, a toda costa, desarrollar procesos de intertextualidad en el estudiantado, dejando de lado los otros niveles indispensables para conseguir el producto final. En este sentido, es vital tener presente que el orden de los factores, en este caso, si alteraría el resultado, ya que velis nolis se debe llevar un ciclo y unos procedimientos específicos para lograr los objetivos trazados con antelación. Por este motivo, es necesario demostrar que las lecturas por menos y encima de lo esperado conforme a unos caracteres y cantidad de fijaciones inciden en la comprensión textual. Por otra parte, en esta investigación se aplicó un diseño transformativo secuencial con enfoque mixto, se seleccionó una muestra de 80 estudiantes de nivel secundario de una institución educativa privada del municipio de Galapa-Colombia, quienes realizaron una lectura de tres textos relacionados con el electromagnetismo en la pantalla del Eye tracker T.120 y con el uso del software Tobii.3.4.6. Los resultados permiten confrontar desde la práctica docente distintas posturas sobre la incursión de estas variables en los procesos lectores. Finalmente, se concluye que las fijaciones visuales cumplen un rol principal para la comprensión de un texto y, por consiguiente, se plantea como prospectiva el diseño de una propuesta didáctica que tome como referente la ciencia y la imagen para buscar la comprensión adecuada por parte del lector.

Context: The complexity in critical patient management and polypharmacy, raise the need for support from a clinical pharmacist to optimize drug therapies. Aims: To evaluate the clinical pharmacist participation in an Adult Intensive Care Unit in a local context where the practice is not well established. Methods: The study was conducted in a teaching hospital. Consisted of two stages a retrospective in which were collected of pharmacotherapy follow-up during a period of two years and a prospective phase of observational and cross-sectional character, which picked up the clinical history of patients and pharmaceutical interventions. These pharmaceutical interventions were evaluated by two intensive care physicians and two external pharmacist, using a default score to each one of these, the degree of concordance was obtained using the kappa coefficient. Results: In the retrospective phase were collected 182 patients, who were performed a total of 750 interventions, of which 99.7% was accepted by physician. In the prospective phase, were analyzed 53 patients that involved 263 pharmaceutical interventions with 96.6% of acceptance on the part of the medical staff. The degree of correlation of the interventions was κ = 0.61 between two physicians of the unit, and κ = 0.71 between two external pharmacists. Conclusions: The contribution that a clinical pharmacist can provide in an adult intensive care has a positive impact on the treatment of patients with a high percentage of acceptances on the part of the medical team.

Context: Critically ill patients has a large number of pathophysiological changes product of commitment and organ systems. Therefore, knowledge of the pharmacological properties of antimicrobials is essential to choose the best treatment. In order to optimize the response of antibiotic therapy and these drugs, new strategies have been proposed dosage, the most used drug application of the model, called: Pharmacokinetics/Pharmacodynamics (PK/PD). In the case of β-lactam antibiotics, the PK/PD model is known as time-dependent on the Minimum Inhibitory Concentration (Time > MIC). For optimal concentrations in β-lactam antibiotics, prolonged or continuous infusions, thus exposing the drug on the pathogen is achieved in a longer optimal concentrations through are used. Aims: To evaluate the therapeutic response of β-lactam antibiotics in critically ill patients with prolonged infusions by applying the model PK/ PD. Methods: Prospective observational study (concurrent cohort), taking as a control non-concurrent historic cohort, conducted for a period of seven months in the intensive care unit of the Hospital Clínico San Borja Arriarán (HCSBA), Santiago, Chile. Results: It was found a significant difference in number of days of hospitalization in ICU for the group bolus versus infusion group (12.5 ± 5.4 vs. 18 ± 9.7 days, IC: 1.5-9.5; p = 0.009). Conclusions: This study suggests that there would be a therapeutic advantage in the use of prolonged infusion in ICU stay duration.

Con el fin de determinar el efecto del calcio y diferentes láminas de riego en plantas de repollo (Brassica oleracea), se sometieron 80 plantas a un diseño completamente al azar, factorial de 3x3, donde el primer factor correspondió a tres niveles de calcio (80, 120 y 160kg x ha-1 de Ca) y el segundo a láminas de riego determinadas por coeficientes (0,8; 1 y 1,2 de la evaporación medida en un evaporímetro construido), más un testigo con una lámina de uno y sin aplicación de calcio, para un total de diez tratamientos. El experimento tuvo una duración de 130 días en invernadero y diez días en laboratorio, para evaluar el comportamiento en poscosecha. Los tratamientos indujeron diferencias significativas para la altura, el área foliar, el peso fresco de hojas, tallo y cabeza, el peso seco de raíz y cabeza, el pH y la pérdida de peso fresco y, altamente significativas para los sólidos solubles totales y el análisis económico. Con la aplicación de la lámina de 0,8 y 160kg x ha-1 de Ca, se obtuvo mayor peso fresco de cabeza y mayor cantidad de fitomasa fresca por cada peso invertido (33,76g x $), por tanto, éste tratamiento es recomendable para ser implementado por los productores de repollo. El suministro de lámina de 1 y 160kg x ha-1 de Ca permitió conservar el repollo en mejores condiciones durante la poscosecha.With the purpose of determining the effect of calcium and different water tables in cabbage (Brassica oleracea) 80 plants were put under a completely randomized design, factorial of 3x3, where the first factor corresponded to three calcium levels (80, 120 and 160kg x ha -1) and the second one to three water tables, determined by using three evaporation coefficients (0.8; 1 and 1.2 of evaporation, measured with an evaporimeter) and a treatment with a water table of 1, without calcium application, for a total of ten treatments. The research was carried out during 130 days in a greenhouse and during ten days under laboratory conditions, to evaluate the post-harvest behavior. The treatments induced significant differences for height, leaf area, fresh weight of leaves, stem and head, dry weight of roots and head, pH and loss of fresh weight; and highly significant differences in total soluble solids and within the economic analysis. With the application of a water table of 0.8 and 160kg x ha-1 of Ca the greatest fresh weight of heads was obtained and a higher fresh phytomass for each inverted peso (33.76g x $). Therefore, this treatment is recommended to be implemented by cabagge producers. The water table of 1 and 160kg x ha-1 of Ca, allowed conserving cabbage in better conditions during post-harvest.