303 research outputs found
Acción del locus TH-insulina en la cardiogénesis
198 p.-34 fig.-4 tab.Tyrosine hydroxylase (TH) and insulin are well-characterized independent genes that are situated in tandem, a syntenic organization that can be traced to the early metazoans. Whereas the roles of these proteins postnatally are well known, the presence and function of the TH-insulin locus in organogenesis is unclear. The aim of this study was to define the expression of Th and insulin genes during cardiac development and to unravel their role in heart formation.
Th expression and activity was analyzed in early chick cardiogenesis. Addition of dopamine induced ectopic expression of Bmp-2, linking TH to early cardiac differentiation programmes.
Overexpression of Th led to increased atrial myosin heavy chain (AMHC-1) and T-box 5 gene (TBX5) expression in the anterior region of the cardiac tube and induced bradyarrhythmia. Exposure to retinoic acid induced the expression of Th in parallel to that of Amhc-1 and Tbx5. Concordantly, inhibition of endogenous retinoic acid synthesis decreased the expression of Th as well as that of Amhc-1 and Tbx5.
Insulin levels were also strictly regulated during cardiac development. The expression of two embryonic mRNA isoforms of insulin, Pro1B and Pro1B1, that differ from the pancreatic transcript was characterized on the embryonic cardiac tube, being the Pro1B1 the predominant isoform after the linear tube formation. Overexpression of the translationally active proinsulin embryonic transcript, Pro1B, and even more of the pancreatic transcript, Pro1A, caused cardiac malformations.
Overexpression of Pro1B led to the reduction of Amhc-1 and Tbx5 expression. Moreover, expansion of Vmhc-1 expression into the posterior region of the cardiac tube was detected.
Thus, TH and insulin are expressed in a dynamic pattern during the primitive heart tube formation. This locus is involved in the network of signals that drive early cardiac chamber specification, acting as a key regulators of the embryonic chick heart morphogenesis.Peer reviewe
Acción del locus TH-insulina en la cardiogénesis
Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 11-04-201
Evaluación de estrés laboral a personal de trabajos críticos de montaje de andamios en empresa Aser Ltda., Viña del Mar
Tesis (Ingeniería en Seguridad y Prevención de Riesgos)El presente proyecto de título se sustenta en la investigación de los diferentes factores que influyen en una de las principales causas de accidentes fatales laborales: caídas de distinto nivel.
En Chile entre los años 2016 y 2017, el porcentaje de participación del riesgo caída a distinto nivel, en la totalidad de accidentes fatales laborales sin participación de vehículos no ha sido menor al 28% (SUSESO, 2017), aun contemplando los programas de prevención y metodologías aplicadas para la reducción de esta estadística en específico. Esto ha sido motivo de discusión en distintos escenarios, desde empresas pequeñas, hasta las más grandes, donde esta accidentabilidad causa pérdidas en múltiples niveles y magnitudes.
Los diversos mercados laborales hoy existentes, ofrecen una amplia gama de trabajos y ocupaciones que permiten al país crecer y a la gente alcanzar sus sueños y metas. Pero el riesgo de accidentabilidad grave o fatal viene a truncar el progreso y trayecto de las personas, siendo los más afectados aquellos que pierden a sus seres amados, quienes, además, por lo general no reciben más que una breve explicación de lo sucedido y se ven obligados a cargar con el peso de la incertidumbre y la duda sobre las causas de lo ocurrido por un largo tiempo; sin mencionar el amplio listado de consecuencias y repercusiones que estos accidentes traen a los distintos actores involucrados o relacionados con el trabajo que se estaba realizando al momento del suceso.
Actualmente, las regulaciones sobre quién es o no apto para lidiar con un riesgo como lo es la caída a distinto nivel, sólo se basan en exámenes físicos y teórico-prácticos sobre su nivel de aptitud para estos cargos y ocupaciones laborales. Y lo que es peor, en ocasiones, aún estas regulaciones son pasadas por alto, debido a la premura del término de obras y cumplimiento de metas de progreso. De lo que se desprenden dos problemas potencialmente peligrosos, primero, la inmensa brecha de desconocimiento sobre la verdadera “aptitud” del personal para realizar trabajos en altura, y segundo, la falta de herramientas o instrumentos específicos para determinar dicha aptitud, esto sin siquiera entrar en el escenario de la regulación del cumplimiento de dichos estándares.
La Norma Chilena 998 Of.1999 “Andamios: Requisitos generales de seguridad” en el punto 6.2.3, menciona: El armado y desarmado de andamios es un trabajo con riesgo de alto potencial y por lo tanto quienes efectúan esta labor deben ser personas técnicamente capacitadas, y aptas física y síquicamente. Considerando la cita anterior, como una ocupación en la que el principal riesgo con el que debe lidiar el trabajador es la caída a distinto nivel, actualmente los organismos administradores y otros centros médicos laborales no se encuentran habilitados para determinar si el trabajador es apto “síquicamente”, por no contar con un instrumento específico designado y desarrollado para determinar el perfil psicológico acorde al cargo a desarrollar.
Siendo lo anterior el común denominador del problema en la mayoría de los cargos y ocupaciones que lidian con el factor de caída a distinto nivel, es que esta memoria de título se concentrará en desarrollar una herramienta de identificación de basada en un perfil psicológico acorde a la naturaleza de este riesgo, que comprenda la detección y nivelación de los postulantes y actuales trabajadores que desarrollen trabajos expuestos a altura física
A Big Data Platform for Real Time Analysis of Signs of Depression in Social Media
In this paper we propose a scalable platform for real-time processing of Social Media data. The platform ingests huge amounts of contents, such as Social Media posts or comments, and can support Public Health surveillance tasks. The processing and analytical needs of multiple screening tasks can easily be handled by incorporating user-defined execution graphs. The design is modular and supports different processing elements, such as crawlers to extract relevant contents or classifiers to categorise Social Media. We describe here an implementation of a use case built on the platform that monitors Social Media users and detects early signs of depressionThis work was funded by FEDER/Ministerio de Ciencia, Innovación y Universidades—Agencia Estatal de Investigación/ Project (RTI2018-093336-B-C21). Our research also receives financial support from the Consellería de Educación, Universidade e Formación Profesional (accreditation 2019–2022 ED431G-2019/04, ED431C 2018/29, ED431C 2018/19) and the European Regional Development Fund (ERDF), which acknowledges the CiTIUS-Research Center in Intelligent Technologies of the University of Santiago de Compostela as a Research Center of the Galician University SystemS
Real-time focused extraction of social media users
In this paper, we explore a real-time automation challenge: the problem of focused extraction of Social Media users. This challenge can be seen as a special form of focused crawling where the main target is to detect users with certain patterns. Given a specific user profile, the task consists of rapidly ingesting Social Media data and early detecting target users. This is a real-time intelligent automation task that has numerous applications in domains such as safety, health or marketing. The volume and dynamics of Social Media contents demand efficient real-time solutions able to predict which users are worth to explore. To meet this aim, we propose and evaluate several methods that effectively allow us to harvest relevant users. Even with little contextual information (e.g., a single user submission), our methods quickly focus on the most promising users. We also developed a distributed microservice architecture that supports real-time parallel extraction of Social Media users. This modular architecture scales up in clusters of computers and it can be
easily adapted for user extraction in multiple domains and Social Media sources. Our experiments suggest that some of the proposed prioritisation methods, which work with minimal user context, are effective at rapidly focusing on the most relevant users. These methods perform satisfactorily with huge volumes of users and interactions and lead to harvest ratios 2 to 9 times higher than those achieved by random prioritisationThis work was supported in part by the Ministerio de Ciencia e Innovación (MICINN) under Grant RTI2018-093336-B-C21 and Grant PLEC2021-007662; in part by Xunta de Galicia under Grant ED431G/08, Grant ED431G-2019/04, Grant ED431C 2018/19, and Grant ED431F 2020/08; and in part by the European Regional Development Fund (ERDF)S
The end of the demographic dividend in Latin America: challenges for economic and social policies
Artículo de revistaPopulation ageing is a major global challenge. The Latin American economies have a younger population structure than other emerging and advanced economies, which has allowed them to enjoy the so-called demographic dividend (a favourable working age/non-working age population ratio). However, according to the latest demographic projections of the United Nations (UN), it is estimated that in 2020 the Latin American population pyramid will resemble that of the advanced economies in 1990 and that, by around 2050, both groups will have similar population profiles. This article documents the current demographic trends in Latin America and discusses the main related challenges, in particular, those arising from the adaptation of social welfare systems to population ageing
Sarcopenia: molecular pathways and potential targets for intervention
Producción CientíficaAging is associated with sarcopenia. The loss of strength results in decreased muscle mass and motor function. This process accelerates the progressive muscle deterioration observed in older adults, favoring the presence of debilitating pathologies. In addition, sarcopenia leads to a decrease in quality of life, significantly affecting self-sufficiency. Altogether, these results in an increase in economic resources from the National Health Systems devoted to mitigating this problem in the elderly, particularly in developed countries. Different etiological determinants are involved in the progression of the disease, including: neurological factors, endocrine alterations, as well as nutritional and lifestyle changes related to the adoption of more sedentary habits. Molecular and cellular mechanisms have not been clearly characterized, resulting in the absence of an effective treatment for sarcopenia. Nevertheless, physical activity seems to be the sole strategy to delay sarcopenia and its symptoms. The present review intends to bring together the data explaining how physical activity modulates at a molecular and cellular level all factors that predispose or favor the progression of this deteriorating pathology.ISABIAL (grant number 190290)Instituto de Salud Carlos III - Fondo Europeo de Desarrollo Regional (CB12/03/30038
Loose Morphology and High Dynamism of OSER Structures Induced by the Membrane Domain of HMG-CoA Reductase
The membrane domain of eukaryotic HMG-CoA reductase (HMGR) has the conserved capacity to induce endoplasmic reticulum (ER) proliferation and membrane association into Organized Smooth Endoplasmic Reticulum (OSER) structures. These formations develop in response to overexpression of particular proteins, but also occur naturally in cells of the three eukaryotic kingdoms. Here, we characterize OSER structures induced by the membrane domain of Arabidopsis HMGR (1S domain). Immunochemical confocal and electron microscopy studies demonstrate that the 1S:GFP chimera co-localizes with high levels of endogenous HMGR in several ER compartments, such as the ER network, the nuclear envelope, the outer and internal membranes of HMGR vesicles and the OSER structures, which we name ER-HMGR domains. After highpressure freezing, ER-HMGR domains show typical crystalloid, whorled and lamellar ultrastructural patterns, but with wide heterogeneous luminal spaces, indicating that the native OSER is looser and more flexible than previously reported. The formation of ER-HMGR domains is reversible. OSER structures grow by incorporation of ER membranes on their periphery and progressive compaction to the inside. The ER-HMGR domains are highly dynamic in their formation versus their disassembly, their variable spherical-ovoid shape, their fluctuating borders and their rapid intracellular movement, indicating that they are not mere ER membrane aggregates, but active components of the eukaryotic cell
Crocus nevadensis Amo & Campo ex Amo (Iridaceae), novedad para la provincia de Toledo = Crocus nevadensis Amo & Campo ex Amo (Iridaceae), new to the province of Toledo
Se publican las primeras citas conocidas para Crocus nevadensis Amo & Campo ex Amo en la provincia de Toledo. Se muestran fotografías tomadas en la fecha y lugar de los hallazgos. ---------- ABSTRACT---------- The first records of Crocus nevadensis Amo & Campo ex Amo in the province of Toledo and photographs of these records are published
Waste and Recycled Materials and their Impact on the Mechanical Properties of Construction Composite Materials
In a world increasingly fixated on the demands of sustainable development, too much attention has been focused on the widely used building materials, mainly on those tools and strategies for their reuse and those characteristics for considering them as environmental-friendly materials. Among the strategies are the following: (a) increased reliability on waste and recycled materials—such action will have to incorporate the substitution of recycled for virgin materials; (b) improved durability through reduction of materials needed for their replacement; and (c) improved mechanical properties, which reduces the use of raw materials. Extensive research and development activities in recycling composite materials have been conducted, and various technologies have been developed: (a) mechanical recycling, (b) thermal recycling, and (c) chemical recycling. However, gamma radiation is an innovative and clean technology, alternative to conventional recycling procedures. Gamma irradiation has proved to be an adequate tool for modifications of the physicochemical properties of polymers, through different effects: (a) scission, branching as well as cross-linking of polymer chains and (b) oxidative degradation. Moreover, the reuse and recycling of waste materials and the use of gamma radiation are useful tools for improving the mechanical properties of concrete. In this chapter, we show results of the effects of gamma irradiation on the physicochemical properties of waste and recycled materials and their reuse to enhance the properties of construction composite materials
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