7,376 research outputs found

    Epilog: Cajal’s unique and legitimated school

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    Santiago Ramón y Cajal is recognized as the founder of modern neuroscience, his discoveries representing the fundamental pillars of our current understanding of the nervous system. As Cajal’s career spanned a critical period in Spanish history, he witnessed strong social demands for progress in culture, education, and science. Indeed, the life of Santiago Ramón y Cajal can be considered to reflect the gradual development of Spanish science from the last third of the 19th century. Cajal promoted a national movement that had important consequences for Spanish science, mainly triggered by the creation of the “Junta para Ampliación de Estudios e Investigaciones Científicas,” an instrument he established to enrich scientific research and that was later to bear such abundant fruit. The school generated by Cajal profited from this development, through which all Cajal’s disciples received fellowships to train in laboratories across Europe. Unfortunately, the Spanish Civil War disrupted this revitalization of Spanish science and provoked the diaspora of many Spanish scientists. However, a political impulse, mostly following this spirit, was resumed in Spain during the eighties that successfully led to a renaissance in Spanish science.The work in the authors’ laboratories is supported by grants (to Juan Lerma) from the Spanish MICINN (BFU2011-24084), CONSOLIDER (CSD2007-00023), Prometeo/2011/086, and BFU2010-21377 (to Juan A. de Carlos).Peer reviewedPeer Reviewe

    Strengthening measurements from the edges: application-level packet loss rate estimation

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    Network users know much less than ISPs, Internet exchanges and content providers about what happens inside the network. Consequently users cannot either easily detect network neutrality violations or readily exercise their market power by knowledgeably switching ISPs. This paper contributes to the ongoing efforts to empower users by proposing two models to estimate -- via application-level measurements -- a key network indicator, i.e., the packet loss rate (PLR) experienced by FTP-like TCP downloads. Controlled, testbed, and large-scale experiments show that the Inverse Mathis model is simpler and more consistent across the whole PLR range, but less accurate than the more advanced Likely Rexmit model for landline connections and moderate PL

    Conjunctival tumors in children: histopathologic diagnosis in 165 cases

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    ABSTRACT Purpose: Conjunctival tissue tumors have a varied presentation, and few series studies on pediatric patients have been published. The objective of this paper is to report the histopathologic diagnoses (spanning over 1988-2013) of conjunctival tumors in children younger than 14 years. Methods: We conducted a retrospective, descriptive, and observational study by reviewing the database of all children in whom a conjunctival tumor was surgically removed at Hospital de Ojos y Oídos "Dr. Rodolfo Robles V.," Benemérito Comité Pro Ciegos y Sordos de Guatemala. The data pertaining to gender, age, and histopathologic diagnosis of all cases was collected. The same ocular pathologist made all diagnoses. Results: One hundred sixty-five cases were found, with a mean age of 7.88 years, being 91 (55.15%) male subjects. Melanocytic lesions were the most common tumors found (30.91% of cases), with only one case (0.60%) being malignant. Conclusions: Melanocytic lesions were the most common tumors found, and of all the cases, only one was malignant; this was in a patient with xeroderma pigmentosum. These findings are consistent with those reported in other studies regarding the frequencies of the histopathology of conjunctival tumors in the pediatric population

    Design and analysis of a mechanical ventilation system based on cams

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    Low-cost mechanical ventilators have been developed in order to deal with the shortage of traditional ventilators whose quantity is not sufficient in an emergency context in Perú. Protofy, a company from Spain, designed one of the first low-cost mechanical ventilation systems OxyGEN which was approved by a medicine agency in its country in special context of COVID 19. Therefore, as main of this article, a redesign of this system named OxygenIP.PE was carried out according to local requirements and available technology, but maintaining its working concept based on compression mechanism by cams. Sensors were added and a control algorithm of the respiratory rate was developed. Ventilation curves monitoring over time was implemented; in this sense, a mathematical model of the whole system was developed. OxygenIP.PE was redesigned, fabricated, and tested measuring its ventilation curves over time. Results indicate that this redesign provides a sturdy equipment able to work during a longer lifetime than the original. The replicability of the ventilation curves behavior is ensured, while the mechanism dimensions are adapted for a particular airbag resuscitator. The mathematical model of the whole system can satisfactorily determine the ventilation curves over time and is used to show the air pressure, volume, and flow as a function of the compression arm's angular position and differential pressure through the breathing circuit measurement, furthermore the algorithms designed as a consequence of the mathematical model were implemented for Raspberry and ARDUINO microcontrollers. There were obtained parameters of pressure 10-65 cmH2O, airflow 50-65 l/m, volume 0-0.5 l, at two values of beat per minute (BPM) 15 and 25

    Estudio de actores y objetivos del Sistema Parlamenta-rio Mexicano mediante el sistema mactor

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    El objetivo del estudio es, identificar los actores y objetivos más impactantes en el sistema legislativo, para poder determinar los conflictos y posibles alianzas estratégicas entre los actores de cara al futuro. Para ello, primero se explicará mediante un marco teórico la función de los legisladores, el poder como un ejercicio sistemático de los actores políticos y la relación de los legisladores con otros actores dentro de la arena política. Posteriormente se dará una explicación de los pasos del sistema MACTOR a través de matrices de actores y objetivos para finalmente realizar el análisis de los resultados de la investigación

    Personal Autonomy Rehabilitation in Home Environments by a Portable Assistive Robot

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    Increasingly disabled and elderly people with mobility problems want to live autonomously in their home environment. They are motivated to use robotic aids to perform tasks by themselves, avoiding permanent nurse or family assistant supervision. They must find means to rehabilitate their abilities to perform daily life activities (DLAs), such as eating, shaving, or drinking. These means may be provided by robotic aids that incorporate possibilities and methods to accomplish common tasks, aiding the user in recovery of partial or complete autonomy. Results are highly conditioned by the system's usability and potential. The developed portable assistive robot ASIBOT helps users perform most of these tasks in common living environments. Minimum adaptations are needed to provide the robot with mobility throughout the environment. The robot can autonomously climb from one surface to another, fixing itself to the best place to perform each task. When the robot is attached to its wheelchair, it can move along with it as a bundle. This paper presents the work performed with the ASIBOT in the area of rehabilitation robotics. First, a brief description of the ASIBOT system is given. A description of tests that have been performed with the robot and several impaired users is given. Insight into how these experiences have influenced our research efforts, especially, in home environments, is also included. A description of the test bed that has been developed to continue research on performing DLAs by the use of robotic aids, a kitchen environment, is given. Relevant conclusions are also included.This work has been supported by the CAM Project S2009/DPI-1559/ROBOCITY2030 I

    A first approach to the Paleoentomology present in the Quaternarian sites of Atapuerca (Burgos, Spain): the subfossil oribatid fauna (Acari, Oribatida)

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    8 páginas, 3 figuras, 2 tablas.[ES] Los yacimientos cuaternarios de la Sierra de Atapuerca ofrecen interés mundial por haber hospedado varias especies de homínidos que vivieron en el último millón de años. En este contexto, durante la campaña de excavaciones de 2003 se realizó un muestreo puntual en algunos de sus yacimientos para obtener los primeros datos de restos de artrópodos que pudieran conservarse en los mismos. En este trabajo se presentan los resultados obtenidos de ácaros subfósiles pertenecientes al suborden de los oribátidos (Acari, Oribatida). Después de procesar los sedimentos, se obtuvieron un total de 7 individuos en el conjunto de los yacimientos muestreados, de los cuales 6 aparecieron en Gran Dolina en un nivel con datación en torno a los 300.000 años. Los ejemplares, identificados en su mayoría a nivel taxonómico de especie, pertenecen a las familias Cosmochthoniidae, Scheloribatidae, Oribatulidae y Hemileiidae. Dado el conocimiento que se dispone de la biología de los taxones encontrados, que pertenecen a géneros y especies presentes en la actualidad, se han realizado inferencias sobre los ambientes pretéritos en que los animales vivieron.[EN] The Atapuerca Quaternarian sites are of worldwide interest due to the presence of human remains belonging to the last million years. The oribatid mites (Acari, Oribatida) found in several archaeological samples extracted from the Atapuerca Quaternarian deposits, have been analyzed during the 2003 excavation campaign to study the Palaeoentomology of the site. The oribatid mite fauna consists of 7 individuals, 6 of which were obtained from Gran Dolina site (about 300.000 years old) and belong to families Cosmochthoniidae, Scheloribatidae, Oribatulidae and Hemileiidae. Most of the taxa were identified to species level. The results obtained were used as a basis to reconstruct the paleo-environments of the site in correspondence with the biological and ecological preferences of the taxa.Las investigaciones entomológicas de Atapuerca se realizaron dentro del Proyecto BOS2003-08938-C03-02.Peer reviewe
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