Influence of Reduced Graphene Oxide and Carbon Nanotubes on the Structural, Electrical, and Photoluminescent Properties of Chitosan Films.

Chitosan is a biopolymer with unique properties that have attracted considerable attention in various scientific fields in recent decades. Although chitosan is known for its poor electrical and mechanical properties, there is interest in producing chitosan-based materials reinforced with carbon-based materials to impart exceptional properties such as high electrical conductivity and high Young's modulus. This study describes the synergistic effect of carbon-based materials, such as reduced graphene oxide and carbon nanotubes, in improving the electrical, optical, and mechanical properties of chitosan-based films. Our findings demonstrate that the incorporation of reduced graphene oxide influences the crystallinity of chitosan, which considerably impacts the mechanical properties of the films. However, the incorporation of a reduced graphene oxide-carbon nanotube complex not only significantly improves the mechanical properties but also significantly improves the optical and electrical properties, as was demonstrated from the photoluminescence studies and resistivity measurements employing the four-probe technique. This is a promising prospect for the synthesis of new materials, such as biopolymer films, with potential applications in optical, electrical, and biomedical bioengineering applications.

Lesiones papilomatosas orales: hiperplasia epitelial focal / Oral papillomatous lesions: Focal epithelial hyperplasia

No disponible

Con los nervios de punta: de la medicalización a la psicologización de los quebrantos mentales en el trabajo. Bogotá y Medellín, 1898-1961 / With the nerves on the top: from medicalization to psychologization of mental breakers at work. Bogota and Medellín, 1898-1961

En este artículo se analizará el modo en que la neurastenia y la fatiga fueron objetivadas por la medicina dentro del ámbito laboral en las ciudades de Bogotá y Medellín, durante la primera mitad del siglo XX. De ahí la necesidad de tomar como referencia la identificación de los presuntos padecimientos ligados a la esfera del trabajo intelectual y físico. A la reivindicación de los comportamientos frugales para aminorar los efectos de aquellos padecimientos, se le vino a adicionar la creciente psicologización del mundo del trabajo promediando dicha centuria. Aquella psicologización se volvió una herramienta que amplió el espectro de la anormalidad, en medio de la metamorfosis experimentada por el aparato productivo y la diversificación de la estructura laboral a nivel nacional

In this article it will analize the way in which nervous exhaustion and fatigue were objectified by the medicine inside the labour environment in the cities of Bogota and Medellin, during the first half of twentieth century. From there the necessity of taking as reference identification of alleged hardship related to intellectual and physical work sphere. To the demand of frugal behaviours to minimize the effects of that hardship, it added the growing psychologization of world work in the middle of the century. That psychologization was turned into a tool that extended the spectrum of anormality, in the midst of the metamorphosis experienced by the productive system and diversification of labour structure nationally

La endoscopia del sueño inducido / Drug-induced sleep endoscopy

Este documento pretende dar a conocer la endoscopia de sueño inducido entre los distintos especialistas que tratan a los pacientes con trastornos respiratorios del sueño y ser una guía para los especialistas que vayan a realizarla de modo que pueda ser reproducible

This document introduces drug-induced sleep endoscopy to the specialist treating sleep breathing disorders and is intended as a guide for those willing to perform the procedure so that it can be reproducible

[Bodies and minds for work: the psychologization of workers in Bogotá and Medellín, 1946-1991]. / Cuerpos y mentes para el trabajo: la psicologización de los trabajadores en Bogotá y Medellín, 1946-1991.

This article seeks to explore the emergence and development of a series of psychological and managerial discourses on worker motivation, organizational climate and quality of life at work in cities like Bogotá and Medellín. This sheds light on the rise and expansion of psychological knowledge applied to the world of work, aimed at optimizing productivity. Strategies for measurement and quantification were put in place that became tools for objectifying behaviors and encouraging a sort of social and labor re-engineering, within the context of growing labor instability and rising unemployment in the late 1980s and early 1990s.

Cuerpos y mentes para el trabajo: la psicologización de los trabajadores en Bogotá y Medellín, 1946-1991 / Bodies and minds for work: the psychologization of workers in Bogotá and Medellín, 1946-1991

Resumen En este artículo se pretende indagar la emergencia y desarrollo de una serie de discursos psicológico-administrativos sobre la motivación laboral, el clima organizacional y la calidad de vida en el trabajo, en ciudades como Bogotá y Medellín. Con ello se trata de dar cuenta del auge y expansión del conocimiento psicológico aplicado al mundo del trabajo y orientado a la optimización de rendimientos. La puesta en marca de estrategias de medición y cuantificación se erigieron en herramientas destinadas a objetivar comportamientos y fomentar una especie de reingeniería socio-laboral, en medio de un contexto caracterizado por la creciente inestabilidad laboral y el incremento del desempleo a finales de la década de 1980 y comienzos del 1990.

Abstract This article seeks to explore the emergence and development of a series of psychological and managerial discourses on worker motivation, organizational climate and quality of life at work in cities like Bogotá and Medellín. This sheds light on the rise and expansion of psychological knowledge applied to the world of work, aimed at optimizing productivity. Strategies for measurement and quantification were put in place that became tools for objectifying behaviors and encouraging a sort of social and labor re-engineering, within the context of growing labor instability and rising unemployment in the late 1980s and early 1990s.

Drug-induced sleep endoscopy. / La endoscopia del sueño inducido.

This document introduces drug-induced sleep endoscopy to the specialist treating sleep breathing disorders and is intended as a guide for those willing to perform the procedure so that it can be reproducible.

Cuerpos y mentes para el trabajo: lapsicologización de los trabajadores enBogotá y Medellín, 1946-1991 / Bodies and minds for work: the psychologization of workers in Bogotá and Medellín, 1946-1991

En este artículo se pretende indagar la emergencia y desarrollo de una serie de discursos psicológico-administrativos sobre la motivación laboral, el clima organizacional y la calidad de vida en el trabajo, en ciudades como Bogotá y Medellín. Con ello se trata de dar cuenta del auge y expansión del conocimiento psicológico aplicado al mundo del trabajo y orientado a la optimización de rendimientos. La puesta en marca de estrategias de medición y cuantificación se erigieron en herramientas destinadas a objetivar comportamientos y fomentar una especie de reingeniería socio-laboral, en medio de un contexto caracterizado por la creciente inestabilidad laboral y el incremento del desempleo a finales de la década de 1980 y comienzos del 1990

¿Comunicar el error médico o esconderlo? A propósito de las memorias de Henry Marsh / Communicate medical error sor hide them? In relation to the henry marsh's memoirs

"Do no harm" es la obra de Henry Marsh, neurocirujano inglés que en el epílogo de su carrera profesional en el National Health Service, hace memoria no tanto de sus éxitos profesionales como de sus fracasos, lo que nos sirve de punto de partida para plantear un sistema de notificación de errores médicos en España que permita cumplir con la máxima hipocrática que da título al libro: "primum non nocere". Con ese objetivo propuesto nos planteamos primero analizar hasta qué punto existe un conflicto de lealtades en la actuación profesional del médico (institución vs. paciente) que condicione la posibilidad de comunicar los errores que se produzcan, concluyendo que existen contrapesos normativos para cumplir con la máxima de informar al paciente respetando otros derechos en conflicto. El equilibrio entre el derecho a estar informado y el derecho a defenderse frente a ulteriores acciones de responsabilidad tiene el fiel de esa imaginaria balanza en la idea canónica de que para aprender del error lo primero es reconocerlo y lo segundo analizar porqué se produjo. Sólo desde el aprendizaje puede evitarse que el error se repita y con ello mejorar la calidad de la asistencia. En el análisis que hacemos del sistema español de comunicación de efectos adversos (SiNASP) llegamos a la conclusión de que no cumple los estándares que nos planteamos, y no sólo desde un análisis ético y jurídico, sino tomando como referencia los sistemas que con el mismo objetivo existen en nuestro entorno europeo, con las referencias de los tratados y acuerdos internacionales en esta materia. La conclusión final a la que llegamos como colofón de toda la reflexión previa es que para que un sistema de comunicación de errores funciones realmente, tiene que ser obligatorio y anónimo para el informante, transparente y concluyente para el informado y, sobre todo, reflexivo y didáctico para la institución, de modo que se cumpla no sólo con el deber de informar sino también con el de evitar que el error se repita

"Do no harm" is the work of Henry Marsh, an English neurosurgeon who, in the epilogue of his professional career at the National Health Service, remembers not only his professional successes but also his failures. This is the starting point to propose a system of notification of medical errors in Spain that allows to comply with the hippocratic key principle that gives title to the book: "primum non nocere". With this objective, our proposal is, in first place, to analyze the extent to which there is a conflict of loyalties in the professional performance of any doctor (institution vs. patient) that conditions the possibility of communicating the errors that may occur, concluding that there are normative counterweights to comply with this principle: to inform the patient respecting other rights in conflict. The balance between the right to be informed and the right to defend oneself against further actions of responsibility has the faithful of that imaginary balance in the canonical idea that to learn from error the starting point is to recognize it, and the second to analyze why it occurred. Only from learning can the error be avoided and, thus, improved the quality of care assistance. In our analysis of the Spanish system of adverse effects communication (SiNASP), we conclude that it does not meet the standards we set ourselves, and not only from an ethical and legal analysis, but also taking as reference the systems with the same Objective in our European environment - including the references of treaties and international agreements in this area. The final conclusion to which we arrive as the culmination of all the previous reflection is that for a system of communication of errors to actually function, it has to be obligatory and anonymous for the informant, transparent and conclusive for the informed and, above all, reflexive and didactic for the institution, so that it fulfils with the duty to inform and it also avoids that the error is repeated

[Communicate Medical Errors or Hide Them? In Relation to the Henry Marsh's Memoirs]. / ¿Comunicar el Error Médico o Esconderlo? A Propósito de las Memorias de Henry Marsh.

″Do no harm″ is the work of Henry Marsh, an English neurosurgeon who, in the epilogue of his professional career at the National Health Service, remembers not only his professional successes but also his failures. This is the starting point to propose a system of notification of medical errors in Spain that allows to comply with the hippocratic key principle that gives title to the book: ″primum non nocere″. With this objective, our proposal is, in first place, to analyze the extent to which there is a conflict of loyalties in the professional performance of any doctor (institution vs. patient) that conditions the possibility of communicating the errors that may occur, concluding that there are normative counterweights to comply with this principle: to inform the patient respecting other rights in conflict. The balance between the right to be informed and the right to defend oneself against further actions of responsibility has the faithful of that imaginary balance in the canonical idea that to learn from error the starting point is to recognize it, and the second to analyze why it occurred. Only from learning can the error be avoided and, thus, improved the quality of care assistance. In our analysis of the Spanish system of adverse effects communication (SiNASP), we conclude that it does not meet the standards we set ourselves, and not only from an ethical and legal analysis, but also taking as reference the systems with the same Objective in our European environment - including the references of treaties and international agreements in this area. The final conclusion to which we arrive as the culmination of all the previous reflection is that for a system of communication of errors to actually function, it has to be obligatory and anonymous for the informant, transparent and conclusive for the informed and, above all, reflexive and didactic for the institution, so that it fulfils with the duty to inform and it also avoids that the error is repeated.

Hepatitis E Virus in Industrialized Countries: The Silent Threat.

Hepatitis E virus (HEV) is the main cause of acute viral hepatitis worldwide. Its presence in developing countries has been documented for decades. Developed countries were supposed to be virus-free and initially only imported cases were detected in those areas. However, sporadic and autochthonous cases of HEV infection have been identified and studies reveal that the virus is worldwide spread. Chronic hepatitis and multiple extrahepatic manifestations have also been associated with HEV. We review the data from European countries, where human, animal, and environmental data have been collected since the 90s. In Europe, autochthonous HEV strains were first detected in the late 90s and early 2000s. Since then, serological data have shown that the virus infects quite frequently the European population and that some species, such as pigs, wild boars, and deer, are reservoirs. HEV strains can be isolated from environmental samples and reach the food chain, as shown by the detection of the virus in mussels and in contaminated pork products as sausages or meat. All these data highlight the need of studies directed to control the sources of HEV to protect immunocompromised individuals that seem the weakest link of the HEV epidemiology in industrialized regions.

Cuerpos y almas para el trabajo: la sicologización del asalariado en Colombia, 1958-1968 / Bodies and souls for work: the psychologization of the wage-earner in Colombia, 1958-1968

Así, este artículo comienza con un incipiente análisis contextual en torno a la configuración de una cierta ética del trabajo, estrechamente vinculada con una primera demarcación entre lo definido socialmente como normal y anormal. Luego de ello, el texto se despliega alrededor de la forma en que se fueron objetivando una serie de presuntas anomalías del obrero, además del abordaje de su intimidad sicológica y de los presuntos complejos que lo aquejaban. (AU)

Mixed-element Octree: a meshing technique toward fast and real-time simulations in biomedical applications.

This article introduces a meshing technique focused on fast and real-time simulation in a biomedical context. We describe in details our algorithm, which starts from a basic Octree regarding the constraints imposed by the simulation, and then, mixed-element patterns are applied over transitions between coarse and fine regions. The use of surface patterns, also composed by mixed elements, allows us to better represent curved domains decreasing the odds of creating invalid elements by adding as few nodes as possible. In contrast with other meshing techniques, we let the user define regions of greater refinement, and as a consequence of that refinement, we add as few nodes as possible to produce a mesh that is topologically correct. Therefore, our meshing technique gives more control on the number of nodes of the final mesh. We show several examples where the quality of the final mesh is acceptable, even without using quality filters. We believe that this new meshing technique is in the correct direction toward real-time simulation in the biomedical field.

Optimización de los medios de propagación y enraizamiento in vitro de las variedades “criollas” de vid para elaborar pisco / Optimization of media for in vitro propagation and rooting of creole

Los protocolos y medios disponibles para la propagación y enraizamiento in vitro de la vid no han sido ajustados todavía a las variedades “criollas” con las que se elabora el pisco. En este trabajo se exploró el uso de medios para la propagación de las variedades Quebranta, Negra Criolla, Albilla, Italia y Torontel, así como para el enraizamiento de las variedades Quebranta, Albilla y Torontel, a partir de los medios estándares reportados en la literatura científica. Para ello, se pusieron a prueba 11 variantes del medio estándar de propagación de vid (medio Murashige y Skoog 1X, 3% de sucrosa, 1 mg/L de benzilaminopurina y 0,8% de agar) en las que se combinaron reducciones en la fuerza del medio con reducciones en la concentración de hormona. Para el enraizamiento posterior, se probaron el ácido naftalen acético y el ácido indol acético a 5 concentraciones distintas por cada hormona. Los resultados mostraron que el mejor medio para la propagación de las variedades Quebranta, Albilla e Italia es el estándar; las variedades Negra Criolla y Torontel tuvieron mejor desempeño con una reducción de la concentración de benzilaminopurina a 0,25 y 0,5 mg/L, respectivamente. El mejor enraizamiento en la variedad Quebranta ocurrió con 80 µg/L de ácido naftalen acético y 2 mg/L de ácido indol acético; las variedades Albilla y Torontel tuvieron una mejor respuesta al ácido indol acético a concentraciones de 2 y 1 mg/L, respectivamente.

The protocols and culture media available for in vitro propagation and rooting of grapevine have not yet been adjusted to the creole varieties used for pisco making. In this paper we explored the use of culture media for the propagation of varieties Quebranta, Negra Criolla, Albilla, Italia and Torontel and for rooting varieties of Quebranta, Albilla and Torontel based on known standard culture media.To address this issue, 11 media derived from the standard propagation medium for grapevine (1X Murashige & Skoog medium, 3% sucrose, 1 mg/L benzilaminopurine, and 0,8% agar) with diminished medium strength and/or hormone concentration were tested. In addition, 5 concentrations of naphtalen acetic acid or indol acetic acid were tested for rooting. We found that Quebranta, Albilla, and Italia varieties show a better growth in the standard propagation medium; by contrast, Negra Criolla and Torontel grew better in media with diminished benzilaminopurine concentrations (0,25 and 0,5 mg/L, respectively). Quebranta rooted better with 80 µg/L naphtalen acetic acid or 2 mg/L indol acetic acid, while Albilla and Torontel showed better rooting results with 2 and 1 mg/L indol acetic acid, respectively.

Restoring diversity after cattail expansion: disturbance, resilience, and seasonality in a tropical dry wetland.

As the human footprint expands, ecologists and resource managers are increasingly challenged to explain and manage abrupt ecosystem transformations (i.e., regime shifts). In this study, we investigated the role of a mechanical disturbance that has been used to restore and maintain local wetland diversity after a monotypic regime shift in northwestern Costa Rica [specifically, an abrupt landscape-scale cattail (Typha) expansion]. The study was conducted in Palo Verde Marsh (Palo Verde National Park; a RAMSAR Wetland of International Importance), a seasonally flooded freshwater wetland that has historically provided habitat for large populations of wading birds and waterfowl. A cattail (T. domingensis) expansion in the 1980s greatly altered the plant community and reduced avian habitat. Since then, Typha has been managed using a form of mechanical disturbance called fangueo (a Spanish word, pronounced "fahn-gay-yo" in English). We applied a Typha removal treatment at three levels (control, fangueo, and fangueo with fencing to exclude cattle grazing). Fangueo resulted in a large reduction in Typha dominance (i.e., decreased aboveground biomass, ramet density, and ramet height) and an increase in habitat heterogeneity. As in many ecosystems that have been defined by multiple and frequent disturbances, a large portion of the plant community regenerated after disturbance (via propagule banking) and fangueo resulted in a more diverse plant community that was strongly dictated by seasonal processes (i.e., distinct wet- and dry-season assemblages). Importantly, the mechanical disturbance had no apparent short-term impact on any of the soil properties we measured (including bulk density). Interestingly, low soil and foliar N:P values indicate that Palo Verde Marsh and other wetlands in the region may be nitrogen limited. Our results quantify how, in a cultural landscape where the historical disturbance regime has been altered and diversity has declined, a mechanical disturbance in combination with seasonal drought and flooding has been used to locally restrict a clonal monodominant plant expansion, create habitat heterogeneity, and maintain plant diversity.

Fisiopatología de los trastornos respiratorios del sueño en los niños / Physiopathology of sleep-disordered breathing in children

Los trastornos respiratorios del sueño representan un amplio espectro de alteraciones que van desde el ronquido habitual, pasando por la hipoventilación obstructiva hasta el síndrome de apnea hipopnea del sueño (SAHS); producen anomalías de la respiración y de la arquitectura durante el sueño. Hay discrepancias entre los mecanismos fisiopatológicos de los trastornos respiratorios del sueño y sus consecuencias metabólicas, neurocognitivas y cardiovasculares. Las causas de comorbilidad del SAHS en los niños no son todavía bien conocidas y pueden incluir anomalías gasométricas sanguíneas, fragmentación del sueño, inflamación local e inflamación sistémica moduladas por factores genéticos, ambientales, raza, etc. La patogénesis de los trastornos respiratorios del sueño pediátricos es, sin lugar a dudas, una compleja interacción entre factores anatómicos o estructurales y funcionales, entre una vía aérea predispuesta al colapso y una compensación neuromuscular deficiente. Además, es necesario tener en cuenta que el sueño del niño evoluciona de acuerdo a la maduración del sistema nervioso central y ésta varía con la edad. En este artículo se revisa el papel de los diferentes factores anatómicos, funcionales e inflamatorios en la fisiopatología de los trastornos respiratorios del sueño pediátricos (AU)

Sleep-disordered breathing represents a broad spectrum of alterations, ranging from habitual snoring, through obstructive hypoventilation to obstructive sleep apnea-hypopnea syndrome, and produces breathing and architecture anomalies during sleep. There are some controversies on the physiopathological mechanisms of sleep-disordered breathing and its metabolic, neurocognitive and cardiovascular effects. The causes of comorbidity in obstructive sleep apnea-hypopnea syndrome in children are not yet well known and can include blood gasometric anomalies, fragmented sleep, and local and systemic inflammation, modulated by genetic, environmental and ethnic factors. The pathogenesis of pediatric sleep-disordered breathing undoubtedly involves complex interactions between anatomical or structural and functional factors, an airway prone to collapse and deficient neuromuscular compensation. Moreover, in children, sleep progresses in accordance with central nervous system development, which varies with age. This article reviews the role of the distinct anatomic, functional and inflammatory factors in the pathophysiology of pediatric sleep-disordered breathing (AU)

Impacts of individual tree species on carbon dynamics in a moist tropical forest environment.

In the moist tropical forest biome, which cycles carbon (C) rapidly and stores huge amounts of C, the impacts of individual species on C balances are not well known. In one of the earliest replicated experimental sites for investigating growth of native tropical trees, we examined traits of tree species in relation to their effects on forest C balances, mechanisms of influence, and consequences for C sequestration. The monodominant stands, established in abandoned pasture in 1988 at La Selva Biological Station, Costa Rica, contained five species in a complete randomized block design. Native species were: Hieronyma alchorneoides, Pentaclethra macroloba, Virola koschnyi, and Vochysia guatemalensis. The exotic species was Pinus patula. By 16 years, the lack of differences among species in some attributes suggested strong abiotic control in this environment, where conditions are very favorable for growth, These attributes included aboveground net primary productivity (ANPP), averaging 11.7 Mg C x ha(-1) x yr(-1) across species, and soil organic C (0-100 cm, 167 Mg C/ha). Other traits differed significantly, however, indicating some degree of biological control. In Vochysia plots, both aboveground biomass of 99 Mg C/ha, and belowground biomass of 20 Mg C/ha were 1.8 times that of Virola (P = 0.02 and 0.03, respectively). Differences among species in overstory biomass were not compensated by understory vegetation. Belowground NPP of 4.6 Mg C x ha(-1) yr(-1) in Hieronyma was 2.4 times that of Pinus (P < 0.01). Partitioning of NPP to belowground components in Hieronyma was more than double that of Pinus (P = 0.03). The canopy turnover rate in Hieronyma was 42% faster than that of Virola (P < 0.01). Carbon sequestration, highest in Vochysia (7.4 Mg C x ha(-1) x yr(-1), P = 0.02), averaged 5.2 Mg C x ha(-1) x yr(-1), close to the annual per capita fossil fuel use in the United States of 5.3 Mg C. Our results indicated that differences in species effects on forest C balances were related primarily to differences in growth rates, partitioning of C among biomass components, tissue turnover rates, and tissue chemistry. Inclusion of those biological attributes may be critical for robust modeling of C cycling across the moist tropical forest biome.

[Physiopathology of sleep-disordered breathing in children]. / Fisiopatología de los trastornos respiratorios del sueño en los niños.

Sleep-disordered breathing represents a broad spectrum of alterations, ranging from habitual snoring, through obstructive hypoventilation to obstructive sleep apnea-hypopnea syndrome, and produces breathing and architecture anomalies during sleep. There are some controversies on the physiopathological mechanisms of sleep-disordered breathing and its metabolic, neurocognitive and cardiovascular effects. The causes of comorbidity in obstructive sleep apnea-hypopnea syndrome in children are not yet well known and can include blood gasometric anomalies, fragmented sleep, and local and systemic inflammation, modulated by genetic, environmental and ethnic factors. The pathogenesis of pediatric sleep-disordered breathing undoubtedly involves complex interactions between anatomical or structural and functional factors, an airway prone to collapse and deficient neuromuscular compensation. Moreover, in children, sleep progresses in accordance with central nervous system development, which varies with age. This article reviews the role of the distinct anatomic, functional and inflammatory factors in the pathophysiology of pediatric sleep-disordered breathing.