Search

Some areas of tropical soils where cocoa grows contain high cadmium (Cd) concentrations. The cocoa plant's need for nutrition causes the reticular system to uptake the toxic metal, translocate it, and accumulate it in roots, stems, and other edible parts such as cocoa beans and shells, threatening the health of cocoa consumers. To cope with this difficulty, different treatments have been applied to cadmium-contaminated soils, but they showed limited success. In this study, we prepared multicomponent nanoparticles (MCNPs) to treat cocoa soils in fixed-bed columns and field tests. Also, MCNPs were mixed with two varieties of cocoa beans, CNN51 and Fino de Aromain, during the fermentation, aiming to capture the cadmium. Our field investigations began by collecting soil samples from three Ecuadorian cocoa-producing farms to determine their physicochemical properties, cadmium, and iron contents. A few weeks later, a home-built prototype was installed in a cocoa plantation to fabricate the nanomaterials using commercial-grade chemicals and rainwater. Scanning Electron Microscope (SEM) images showed MCNPs with an average size of 65.21 nm and the formation of chain-like aggregates. In contrast, MCNPs size was 76.6 nm, measured with Dispersed Light Scattering (DLS). The chemical composition of MCNPs was 90.7 % Fe0 and 1.81 % sulfur (S), analyzed by energy dispersal X-ray (EDX) and confirmed by X-ray diffraction (XRD) spectrometer measurements. Regarding the treatments, for the fixed-bed column tests, 0.28–1.08 L/kg was dosed into the soil, while for field treatments, 250, 500, and 835 mL/min MCNPs were injected in soil areas of 5 m2 surrounding each cocoa tree (0.5–4.5 mg MCNPs/kg soil) at depths between 0 and 5 cm. Test results revealed that the procedure applied in the field did not reproduce the metal's immobilization (∼22 %) as in the fixed-bed columns (∼80 %). Moreover, cadmium removal was ∼20 % and ∼75 % after treating CCN51 and Fino de Aroma cocoa beans with 0.112 kg MCNPs/kg in the fermentation on-site and 0.034 kg MCNPs/kg in the laboratory. In this study, the size and chain-like aggregates of MCNPs notably influenced the field treatments as they precluded the filtration of MCNPs downwards. However, immobilizing cadmium could be more effective in soils with higher concentrations of the metal and multicomponent nanoparticles of smaller size, expanding our research scope and offering a practical solution to pollution issues in cocoa-growing regions.

Los ciberataques aumentan cada vez más, a partir de incremento del uso del internet como medio para realizar transacciones económicas, medio de comunicación y herramienta de almacenar información. Ante esto, las organizaciones de todos los sectores y sus liderazgos se encuentran en la necesidad de atender estos riesgos crecientes a partir de políticas en materia de ciberseguridad. La presente investigación corresponde a una revisión teórica documental y/o bibliográfica de carácter deductivo. Es objetivo de este trabajo es describir los desafíos en materia de ciberseguridad que afronta el liderazgo transformacional. Entre los hallazgos del trabajo, destacamos que los líderes deben involucrar a la mayor cantidad de miembros de la organización en los procesos de cambio, favoreciendo su capacitación en la materia, los cuáles son necesarios para garantizar la sostenibilidad y crecimiento de la organización. Las políticas en materia de ciberseguridad deben garantizar el desarrollo de la economía digital y el libre mercado. Se concluye que la ciberseguridad debe tratarse como un asunto integral y multidimensional.

El propósito del presente estudio estuvo centrado en develar las tendencias gerenciales en las organizaciones enfocándose en la gerencia, sus competencias y efectividad gerencial. La investigación corresponde a una revisión teórica documental y/o bibliográfica. Las revelaciones indicaron que la gerencia debe llevar a cabo un plan estratégico, mediante la organización y el nombramiento de personal, creando una estructura que impulse al personal a alcanzar los objetivos, resolviendo problemas, y confrontando los resultados persistentes en la empresa. Como reflexión final, se hace importante que todo el personal labore con eficiencia, y esto depende, en parte, de la capacidad de quienes ejercen funciones gerenciales, considerándose los avances científicos y tecnológicos sobre las nuevas tendencias de la gerencia; así como el desarrollo de los conocimientos, para que se realice una efectiva aplicación del hacer cotidiano y gestión de recursos requeridos, además, que se hace necesaria que dicha organización se esfuerce por dar respuestas a las exigencias de la globalización, a los cambios y la valoración del capital humano, como esencia de la misma, manteniendo a la vez, sus estándares de competencia y calidad.

Introducción: La sociedad está envejeciendo, y se estima que este segmento seguirá aumentando en los próximos años. Objetivo: Examinar los efectos que producen 5 semanas de entrenamiento en el rendimiento funcional, fuerza de agarre, perímetro de cintura, masa grasa y percepción de dolor general. Método: 28 sujetos (edad ≥ 55 años), sedentarios, participaron en un programa de entrenamiento de fuerza y entrenamiento aeróbico, de 5 semanas, 5 sesiones semanales de 50-60 minutos de duración. Resultados: Existen diferencias estadísticamente significativas entre los valores previos y posteriores al programa. La magnitud de estas diferencias puede considerarse grande en el Timed Up and Go Test (-27.3%, p=0.000, d=3.01), 30-Second Chair Stand Test (+42%, p=0.000, d=1.77) y percepción de dolor día (-54.7%, p=0.000, d=1.27) y noche (-58.2%, p=0.000, d=1.02). Conclusión: Tras la aplicación del programa de entrenamiento concurrente descrito, todas las variables analizadas han evolucionado favorablemente. Dichas variables están directamente relacionadas con la composición corporal, calidad de vida, reducción del dolor, así como mejora de fuerza para las actividades cotidianas de las personas mayores. Abstract. Introduction: Society is aging, and it is estimated that this segment will continue to grow in the coming years. Objectives: To examine the effects of 5 weeks of training on functional performance, grip strength, waist circumference, fat mass and general pain perception.Methods: 28 subjects (age ≥ 55 years), sedentary, participated in a 5-week strength and aerobic training program, 5 weekly sessions of 50-60 minutes duration. Results: There are statistically significant differences between pre and post program values. The magnitude of these differences can be considered large in the Timed Up and Go Test (-27.3%, p=0.000, d=3.01), 30-Second Chair Stand Test (+42%, p=0.000, d=1.77) and pain perception day (-54.7%, p=0.000, d=1.27) and night (-58.2%, p=0.000, d=1.02).Conclusion: After the application of described concurrent training program, all analyzed variables have evolved favorably. Such variables are directly related to body composition, quality of life, pain reduction, as well as to improvement of strenght for the elderly’s daily activities.

Como elementos clave de la sociedad contemporánea, las organizaciones, desde antes del siglo XX, han transitado por diferentes realidades, desarrollando y consolidando modelos de gestión acordes a las necesidades de los contextos actuales y necesarios para una gestión eficiente de los recursos disponibles. Bajo estos escenarios, se justifican modelos alternativos o emergentes, que surgen como visiones contrarias a los modelos tradicionales. Así, el objetivo de esta investigación, se centra en caracterizar los rasgos distintivos de un modelo de gestión emergente tomando como elementos centrales la toma de decisiones, la estructura organizativa y el control organizacional. Apoyados en la revisión bibliográfica documental y análisis crítico de documentos, se precisan como hallazgos importantes, modelos alternativos que se han venido gestando en las economías locales de la región latinoamericana, llegando a concluir que, el asumir visiones contrarias a lógicas tradicionales, trastoca elementos esenciales de la praxis administrativa. Nuevas formas de pensamientos al momento de tomar decisiones, y de organización recursos en las estructuras, así como nuevos mecanismos de control, surgen y se van afinando con el transitar de los años, de manera que llegue un día donde visiones emergentes, logren sobrepasar las lógicas tradicionales apegadas a modelos de gestión que en otrora respondieron a las exigencias de los contextos.

Optimization models in metabolic engineering and systems biology focus typically on optimizing a unique criterion, usually the synthesis rate of a metabolite of interest or the rate of growth. Connectivity and non-linear regulatory effects, however, make it necessary to consider multiple objectives in order to identify useful strategies that balance out different metabolic issues. This is a fundamental aspect, as optimization of maximum yield in a given condition may involve unrealistic values in other key processes. Due to the difficulties associated with detailed non-linear models, analysis using stoichiometric descriptions and linear optimization methods have become rather popular in systems biology. However, despite being useful, these approaches fail in capturing the intrinsic nonlinear nature of the underlying metabolic systems and the regulatory signals involved. Targeting more complex biological systems requires the application of global optimization methods to non-linear representations. In this work we address the multi-objective global optimization of metabolic networks that are described by a special class of models based on the power-law formalism: the generalized mass action (GMA) representation. Our goal is to develop global optimization methods capable of efficiently dealing with several biological criteria simultaneously. In order to overcome the numerical difficulties of dealing with multiple criteria in the optimization, we propose a heuristic approach based on the epsilon constraint method that reduces the computational burden of generating a set of Pareto optimal alternatives, each achieving a unique combination of objectives values. To facilitate the post-optimal analysis of these solutions and narrow down their number prior to being tested in the laboratory, we explore the use of Pareto filters that identify the preferred subset of enzymatic profiles. We demonstrate the usefulness of our approach by means of a case study that optimizes the ethanol production in the fermentation of Saccharomyces cerevisiae.

Copyright of COMUNI@CCION - Revista de Investigación en Comunicación y Desarrollo is the property of Universidad Nacional del Altiplano and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background Mortality due to COVID-19 is high, especially in patients requiring mechanical ventilation. The purpose of the study is to investigate associations between mortality and variables measured during the first three days of mechanical ventilation in patients with COVID-19 intubated at ICU admission. Methods Multicenter, observational, cohort study includes consecutive patients with COVID-19 admitted to 44 Spanish ICUs between February 25 and July 31, 2020, who required intubation at ICU admission and mechanical ventilation for more than three days. We collected demographic and clinical data prior to admission; information about clinical evolution at days 1 and 3 of mechanical ventilation; and outcomes. Results Of the 2,095 patients with COVID-19 admitted to the ICU, 1,118 (53.3%) were intubated at day 1 and remained under mechanical ventilation at day three. From days 1 to 3, PaO2/FiO2 increased from 115.6 [80.0–171.2] to 180.0 [135.4–227.9] mmHg and the ventilatory ratio from 1.73 [1.33–2.25] to 1.96 [1.61–2.40]. In-hospital mortality was 38.7%. A higher increase between ICU admission and day 3 in the ventilatory ratio (OR 1.04 [CI 1.01–1.07], p = 0.030) and creatinine levels (OR 1.05 [CI 1.01–1.09], p = 0.005) and a lower increase in platelet counts (OR 0.96 [CI 0.93–1.00], p = 0.037) were independently associated with a higher risk of death. No association between mortality and the PaO2/FiO2 variation was observed (OR 0.99 [CI 0.95 to 1.02], p = 0.47). Conclusions Higher ventilatory ratio and its increase at day 3 is associated with mortality in patients with COVID-19 receiving mechanical ventilation at ICU admission. No association was found in the PaO2/FiO2 variation.

Summary: Background: The clinical heterogeneity of COVID-19 suggests the existence of different phenotypes with prognostic implications. We aimed to analyze comorbidity patterns in critically ill COVID-19 patients and assess their impact on in-hospital outcomes, response to treatment and sequelae. Methods: Multicenter prospective/retrospective observational study in intensive care units of 55 Spanish hospitals. 5866 PCR-confirmed COVID-19 patients had comorbidities recorded at hospital admission; clinical and biological parameters, in-hospital procedures and complications throughout the stay; and, clinical complications, persistent symptoms and sequelae at 3 and 6 months. Findings: Latent class analysis identified 3 phenotypes using training and test subcohorts: low-morbidity (n=3385; 58%), younger and with few comorbidities; high-morbidity (n=2074; 35%), with high comorbid burden; and renal-morbidity (n=407; 7%), with chronic kidney disease (CKD), high comorbidity burden and the worst oxygenation profile. Renal-morbidity and high-morbidity had more in-hospital complications and higher mortality risk than low-morbidity (adjusted HR (95% CI): 1.57 (1.34-1.84) and 1.16 (1.05-1.28), respectively). Corticosteroids, but not tocilizumab, were associated with lower mortality risk (HR (95% CI) 0.76 (0.63-0.93)), especially in renal-morbidity and high-morbidity. Renal-morbidity and high-morbidity showed the worst lung function throughout the follow-up, with renal-morbidity having the highest risk of infectious complications (6%), emergency visits (29%) or hospital readmissions (14%) at 6 months (p

Abstract Background The identification of factors associated with Intensive Care Unit (ICU) mortality and derived clinical phenotypes in COVID-19 patients could help for a more tailored approach to clinical decision-making that improves prognostic outcomes. Methods Prospective, multicenter, observational study of critically ill patients with confirmed COVID-19 disease and acute respiratory failure admitted from 63 ICUs in Spain. The objective was to utilize an unsupervised clustering analysis to derive clinical COVID-19 phenotypes and to analyze patient’s factors associated with mortality risk. Patient features including demographics and clinical data at ICU admission were analyzed. Generalized linear models were used to determine ICU morality risk factors. The prognostic models were validated and their performance was measured using accuracy test, sensitivity, specificity and ROC curves. Results The database included a total of 2022 patients (mean age 64 [IQR 5–71] years, 1423 (70.4%) male, median APACHE II score (13 [IQR 10–17]) and SOFA score (5 [IQR 3–7]) points. The ICU mortality rate was 32.6%. Of the 3 derived phenotypes, the A (mild) phenotype (537; 26.7%) included older age ( 65 years), high severity of illness and a higher likelihood of development shock. Crude ICU mortality was 20.3%, 25% and 45.4% for A, B and C phenotype respectively. The ICU mortality risk factors and model performance differed between whole population and phenotype classifications. Conclusion The presented machine learning model identified three clinical phenotypes that significantly correlated with host-response patterns and ICU mortality. Different risk factors across the whole population and clinical phenotypes were observed which may limit the application of a “one-size-fits-all” model in practice.