Functional anatomy of non-REM sleep

The state of non-REM sleep (NREM), or slow wave sleep, is associated with a synchronized EEG pattern in which sleep spindles and/or K complexes and high-voltage slow wave activity (SWA) can be recorded over the entire cortical surface. In humans, NREM is subdivided into stages 2 and 3–4 (presently named N3) depending on the proportions of each of these polygraphic events. NREM is necessary for normal physical and intellectual performance and behavior. An overview of the brain structures involved in NREM generation shows that the thalamus and the cerebral cortex are absolutely necessary for the most significant bioelectric and behavioral events of NREM to be expressed; other structures like the basal forebrain, anterior hypothalamus, cerebellum, caudal brain stem, spinal cord and peripheral nerves contribute to NREM regulation and modulation. In NREM stage 2, sustained hyperpolarized membrane potential levels resulting from interaction between thalamic reticular and projection neurons gives rise to spindle oscillations in the membrane potential; the initiation and termination of individual spindle sequences depends on corticothalamic activities. Cortical and thalamic mechanisms are also involved in the generation of EEG delta SWA that appears in deep stage 3–4 (N3) NREM; the cortex has classically been considered to be the structure that generates this activity, but delta oscillations can also be generated in thalamocortical neurons. NREM is probably necessary to normalize synapses to a sustainable basal condition that can ensure cellular homeostasis. Sleep homeostasis depends not only on the duration of prior wakefulness but also on its intensity, and sleep need increases when wakefulness is associated with learning. NREM seems to ensure cell homeostasis by reducing the number of synaptic connections to a basic level; based on simple energy demands, cerebral energy economizing during NREM sleep is one of the prevalent hypotheses to explain NREM homeostasis.Grant BFU2009-06991/BFI from the Spanish Ministry of Science and Innovation supported this wor

Configuraciones y dinámicas de la violencia organizada en colombia 1987 - 1997

El artículo es una síntesis de una monografía evaluada como meritoria por los jurados. El autor se propone aplicar la teoría de la acción social para entender las estrategias de los actores organizados de la violencia colombiana en la etapa más reciente

Una verdad con muchos interrogantes: preguntas incómodas sobre las cifras oficiales del conflicto armado en Colombia

Figures are often cloaked in a mantle of veracity and forcefulness, which few people replicate because they are thought to be a reflection of reality and the data are mere aggregations of verifiable facts. This article asks uncomfortable questions of four official figures of the armed conflict, and it reveals their implications for struggles for truth. Its emphasis is on how contexts, mediators, and methodological decisions interfere with the production of data and how the presentation of these data constrains the public debate over responsibilities and victims of the armed conflict.Las cifras suelen revestirse con un manto de veracidad y contundencia que pocos replican porque se piensa que éstas son un reflejo de la realidad y que los datos son meras agregaciones de hechos constatables. Este artículo hace preguntas incómodas a cuatro cifras oficiales del conflicto armado y revela sus implicaciones en las luchas por la verdad. Su énfasis se pone en cómo los contextos, los mediadores y las decisiones metodológicas interfieren en la producción de datos y cómo la presentación de estos condiciona el debate público por las responsabilidades y las víctimas del conflicto armado

Saevitia in the massacres of the colombian war

Starting from a description of the massacres in the region of Urabá between 1988 and 2002, this text formulates as a hypothesis that the appearance of saevitia (excessive cruelty) depends on factors such as war space/time, representations of the enemy, military asymmetry and insufficient use of political approaches. According to the author, the characteristics of saevitia in the massacres during the recent decades in the Colombian conflict contrasts with the period known as The Violence (1946-1965), which not only reflects a change in the phenomenology of terror but in the nature of contemporary political violence.A partir de una descripción de las masacres en la región de Urabá entre 1988 y 2002, el presente texto formula como hipótesis que el desencadenamiento de la sevicia depende de factores como el espacio/tiempo de la guerra, las representaciones del enemigo, la asimetría militar y las carencias de explotación de lo político. Según el autor, las características de la sevicia en las masacres de las décadas recientes del conflicto colombiano van a marcar un contraste con el periodo de La Violencia (1946-1965), lo cual refleja no sólo un cambio en la fenomenología del terror sino en la naturaleza de la violencia política contemporánea

High-Temperature Mechanical Properties of IN718 Alloy: Comparison of Additive Manufactured and Wrought Samples

Wire Arc Additive Manufacturing (WAAM) is one of the most appropriate additive manufacturing techniques for producing large-scale metal components with a high deposition rate and low cost. Recently, the manufacture of nickel-based alloy (IN718) using WAAM technology has received increased attention due to its wide application in industry. However, insufficient information is available on the mechanical properties of WAAM IN718 alloy, for example in high-temperature testing. In this paper, the mechanical properties of IN718 specimens manufactured by the WAAM technique have been investigated by tensile tests and hardness measurements. The specific comparison is also made with the wrought IN718 alloy, while the microstructure was assessed by scanning electron microscopy and X-ray diffraction analysis. Fractographic studies were carried out on the specimens to understand the fracture behavior. It was shown that the yield strength and hardness of WAAM IN718 alloy is higher than that of the wrought alloy IN718, while the ultimate tensile strength of the WAAM alloys is difficult to assess at lower temperatures. The microstructure analysis shows the presence of precipitates (laves phase) in WAAM IN718 alloy. Finally, the effect of precipitation on the mechanical properties of the WAAM IN718 alloy was discussed in detail.This project received funding from the European Union’s Marie Skłodowska–Curie Actions (MSCA) Innovative Training Networks (ITN) H2020-MSCA-ITN-2017 under the grant agreement No. 764979 and Basque Government QUALYFAM project, ELKARTEK 2020 program (KK-2020/00042) and HARIPLUS project, HAZITEK 2019 program (ZL-2019/00352)

Review of Intermediate Strain Rate Testing Devices

Materials undergo various loading conditions during different manufacturing processes, including varying strain rates and temperatures. Research has shown that the deformation of metals and alloys during manufacturing processes such as metal forming, machining, and friction stir welding (FSW), can reach a strain rate ranging from 10−1 to 106 s−1. Hence, studying the flow behavior of materials at different strain rates is important to understanding the material response during manufacturing processes. Experimental data for a low strain rate of 103 s−1 are readily available by using traditional testing devices such as a servo-hydraulic testing machine and the split Hopkinson pressure bar method, respectively. However, for the intermediate strain rate (101 to 103 s−1), very few testing devices are available. Testing the intermediate strain rate requires a demanding test regime, in which researchers have expanded the use of special instruments. This review paper describes the development and evolution of the existing intermediate strain rate testing devices. They are divided based on the loading mechanism; it includes the high-speed servo-hydraulic testing machines, hybrid testing apparatus, the drop tower, and the flywheel machine. A general description of the testing device is systematically reviewed; which includes the working principles, some critical theories, technological innovation in load measurement techniques, components of the device, basic technical assumption, and measuring techniques. In addition, some research direction on future implementation and development of an intermediate strain rate apparatus is also discussed in detail.This project received funding from the European Union’s Marie Skłodowska–Curie Actions (MSCA) Innovative Training Networks (ITN) H2020-MSCA-ITN-2017 under the grant agreement No. 76497

The relationship between working conditions and health status in working population that is affiliated to the colombian general system for occupational risk management

ABSTRACT: To analyze the relationship between working conditions and health status using the data provided by The First Colombian National Survey on Health and Working Conditions (I-ENCST). Methods: a cross-sectional study was conducted on 931 workers from 737 work centers. The outcome variable was self-perceived health status (good/ poor). Exposure variables were working conditions, i.e. hygiene, safety, ergonomic, and psychosocial risk factors. Additional variables were: sex, age, social class, education level, geographic region, and economic activity. We estimated the relationship between working conditions and health status using crude odds ratios (OR) that were adjusted through logistic regression with their confidence intervals at 95% (CI95%). Results: workers exposed to the following factors had a higher probability of having a poor health status: insufficient working space (aOR 3.9; 95%CI 1.9-8.3), “the position held does not make it possible to develop skills” (aOR 6.2; 95%CI 2.6-14.7), the work center is very unsafe or not very safe (aOR 7.5; 95%CI 3.0-18.6), and the tools or workstation are inadequate (aOR 5.6; 95%CI 2.3-14.0). Discussion: of the analyzed population, individuals exposed to precarious working conditions had a higher risk of having a poor health status.RESUMEN:Analizar la relación entre las condiciones de trabajo y el estado de salud a partir de los datos de la I Encuesta Nacional de Condiciones de Salud y Trabajo en el Sistema General de Riesgos Profesionales de Colombia (i-encst). Métodos: estudio transversal (931 trabajadores -737 centros de trabajo). La variable resultado fue la percepción del estado de salud (Buena/ Mala). Las variables de exposición fueron las condiciones de trabajo (factores de riesgos higiénicos, seguridad, ergonómicos y psicosociales). Otras variables: sexo, edad, clase social, nivel educativo, región geográfica y actividad económica. Se estimó la relación entre las condiciones de trabajo y el estado de salud por medio de Odds Ratio (OR) crudas y ajustadas por regresión logística con sus intervalos de confianza al 95% (IC95%). Resultados: la población trabajadora expuesta a espacio reducido para la tarea (ORa 3,9; IC95% 1,9-8,3), “el cargo desempeñado no permite el desarrollo de habilidades” (ORa 6,2; IC95% 2,6-14,7), centro de trabajo muy inseguro o poco seguro para trabajar (ORa 7,5; IC95% 3,0-18,6) y medios o herramientas insuficientes (ORa 5,6; IC95% 2,3-14,0), entre otros factores, reportaron mayor probabilidad de tener mala salud. Discusión: la población analizada expuesta a condiciones de trabajo precarias tuvo mayor riesgo de mala salud

Scoping Review About Working Conditions and Health of Immigrant Workers in Spain

Fundamentos: La relación entre inmigración, trabajo y salud constituye uno de los retos más importantes en salud laboral y más concretamente en España por el importante incremento de proporción inmigrante acontecido en el mercado laboral. El objetivo de esta investigación es conocer la relación entre las condiciones de trabajo y sus efectos en la salud de trabajadores inmigrantes en España. Métodos: Revisión bibliográfica de artículos científicos originales en español e inglés Medline y Medes (1998-2012). Se revisaron los textos completos de los artículos incluidos. Resultados: Se incluyeron 20 estudios, 13 con metodología de investigación cuantitativa y 7 cualitativa. Los temas tratados abordaban problemas específicos de salud relacionados con el trabajo (principalmente lesiones por accidente de trabajo), incapacidad laboral y diferencias en condiciones de trabajo y empleo. Los hallazgos de los estudios mostraron mayor incidencia de lesiones por accidentes de trabajo, menores tasas de incapacidad laboral, mayor prevalencia de presentismo laboral, exposición a factores psicosociales y precariedad laboral en la población inmigrante. Conclusiones: A pesar de la singularidad del proceso demográfico migratorio, los problemas de salud y determinantes identificados no difieren de los referenciados en otros países, en otros contextos y en otros momentos.Background:The relationship between immigration, work, and health is one of the most important challenges in occupational health at current, particularly in Spain, by the significant increase in the migrant workers in the labor market occurred. This investigation aims to know the relationship betwen working conditions and their effects on migrant workers. Methods: Scoping review of scientific papers on this topic at the Medline and Medes databases in Spanish and English (1998-2012). The articles included were full text reviewed. Results: 20 studies were included, 13 with quantitative methodology and 7 qualitative. The topics address specific health problems related to work (primarily occupational accidents), disability, and differences in working conditions and employment. The findings of the studies show a higher incidence of injury accidents, lower rates of disability, higher prevalence of work presenteeism, exposure to psychosocial factors, and precariousness. Conclusion: Despite the uniqueness of the demographic process migration happened in Spain, health problems and determinants identified no different from those referenced in other countries, in other contexts and in other times

Perceptions of female immigrant domestic workers on the effects of the sector regulation in Spain

Objetivo: Explorar las percepciones de las mujeres inmigrantes trabajadoras del servicio doméstico sobre la puesta en vigor en España del Real Decreto 1620/2011, que regula la relación laboral del servicio del hogar familiar, y su efecto en sus condiciones de empleo. Métodos: Estudio exploratorio mediante análisis de contenido cualitativo. Se realizaron tres grupos de discusión con mujeres inmigrantes (colombianas, ecuatorianas y marroquíes). Resultados: A pesar de valorar positivamente los beneficios teóricos de la nueva normativa, las mujeres inmigrantes han identificado barreras legales y económicas para conseguir un contrato, ser dadas de alta en la seguridad social y que las personas empleadoras asuman su coste, en especial en el caso de las trabajadoras contratadas por horas. Estas dificultades influyen en la posibilidad de legalizar su situación. La confluencia con la crisis económica ha emergido como un problema que dificulta su cumplimiento. Conclusiones: Aunque el nuevo régimen ha favorecido la creación de puestos de trabajo con mayores derechos laborales en el sector, las mujeres inmigrantes perciben que su puesta en marcha en el actual contexto de crisis económica no ha contribuido a mejorar sus condiciones de empleo.Objective: To examine the perceptions of female immigrant domestic workers of the effect of Royal Decree 1620/2011, which regulates the relationship of domestic workers in the family home and their employment conditions in Spain. Methods: An exploratory study was performed using qualitative content analysis of three focus group discussions with immigrant women from Colombia, Ecuador and Morocco. Results: Immigrant women positively assessed the theoretical benefits of the new regulation, but identified legal and economic barriers to obtaining a contract and being registered in the social security system by their employers, and to employers accepting the cost of these measures, especially for workers hired by the hour. These difficulties affected their possibilities of legalizing their status. The economic crisis posed a serious challenge to compliance with the new regulation. Conclusions: Although the new regime encourages job creation with stronger working rights for these workers, immigrant women perceived that its implementation has been hampered by the current financial crisis and has not, therefore, improved their employment conditions.FIS (PI11/01192)

Rediseño de la distribución de planta aplicado a Isoplasticos S.A.S.

The purpose of this research is to solve an engineering problem by designing an adjustable solution for other similar conditions. The chosen situation was the layout redistribution of an injection and blow molding company, called ISOPLASTICOS S.A.S. which is currently in an accelerated growth addressed by its main client. In order to solve this problem, a solution methodology was designed based on the theories of the SLP, Systematic Layout Planning. The methodology DMAIC was used as the way to approach the problem.Ingeniero (a) IndustrialPregrad