711 research outputs found

    The enteric nervous system : new developments and emerging concepts

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    The enteric nervous system (ENS) is an integrative neuronal network, organized in two ganglionated plexuses, myenteric and submucosal, composed of neurons and enteric glial cells, controlling the activity of the smooth muscle of the gut, mucosal secretion and blood flow. The ENS contains as many neurons as the spinal cord, and the functional and chemical diversity of enteric neurons closely resembles that of the central nervous system. This highly integrated neural system is also referred to as the ‘brain-in-the-gut’, because of its capability to function in the absence of nerve inputs from the central nervous system.peer-reviewe

    Aspetti psicopatologici dell'epilessia in età evolutiva

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    Nell'ambito dell'argomento che ci accingiamo a trattare qualsiasi generalizzazione appare improponibile. Improponibile proprio per le difficoltà implicite nel fatto che ogni bambino organizza la propria personalità intorno alla sua epilessia, con questa vive e progressivamente si evolve e, attraverso la propria storia personale, approda ad equilibri dinamici che sono squisitamente individuali e rappresentano il risultato di numerose variabili. Importanza particolare assumono infatti, a questo proposito, l'età di insorgenza della malattia, il patrimonio personologico precedente, quello intellettivo attuale, il tipo e la frequenza delle crisi, i rapporti che si stabiliscono fra famiglia e malato a proposito delle crisi

    The enteric nervous system : new developments and emerging concepts

    Get PDF
    The enteric nervous system (ENS) is an integrative neuronal network, organized in two ganglionated plexuses, myenteric and submucosal, composed of neurons and enteric glial cells, controlling the activity of the smooth muscle of the gut, mucosal secretion and blood flow. The ENS contains as many neurons as the spinal cord, and the functional and chemical diversity of enteric neurons closely resembles that of the central nervous system. This highly integrated neural system is also referred to as the ‘brain-in-the-gut’, because of its capability to function in the absence of nerve inputs from the central nervous system.peer-reviewe

    The legitimate competition for the government monopoly

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    The enchanted narration of representative regimes, despite their practice, today is so omnipotent that contradicting it is worthwhile. Deleting the rhetoric with which they legitimate themselves, the author shows the nature of government technique and dominion form that minimizes coercion. What comes to surface is a weave made of oscillations: between political synthesis of government action and recomposition of pluralism.A despecho de su práctica, el cuento maravilloso del régimen representativo hoy día es tan omnipotente como para que valga la pena contradecirlo. Despojándola de la retórica con la que se legitima, el autor analiza la naturaleza de la técnica de gobierno y de la forma de dominio que minimiza la coerción. De ahí que sobresalga una trama compuesta por oscilaciones entre la síntesis política de la acción de gobierno y la recomposición del pluralismo

    Design, fabrication and characterisation of silicon carbide resonators

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    Micro-electro-mechanical systems (MEMS) are integrated mechanical and electrical elements realised with micro-fabrication technology and employed as sensors and actuators. The integration of reliable MEMS switches and resonators into transceiver devices is a challenging and attractive solution to increase the efficiency and reduce the power consumption. Silicon carbide (SiC) is an excellent candidate for developing robust and reliable high frequency MEMS for transceivers applications due to its unique mechanical properties.This thesis presents the design, fabrication and characterisation of 3C-SiC micromechanical vertical resonators. New device architectures have been developed for the study of the electro-mechanical behaviour of the devices with the aim of optimising the actuation efficiency, increasing the resonant frequency and obtaining new device functions.A process for the fabrication of single or poly-crystalline 3C-SiC cantilevers, bridges and rings has been developed with the option of integrating top electrodes made of aluminium (Al) or lead zirconium titanate (PZT). The crystal structure and quality of the SiC layers have been evaluated with X-ray diffraction and Raman spectroscopy. A Young's Modulus of ~ 440 GPa has been calculated for the single crystalline SiC from the mechanical resonant frequency of the fabricated single material cantilevers. The fabricated Al/SiC bridges and rings have been actuated and driven into resonance electro-thermally. It has been found that wide Al electrodes applied close to the beams' anchor can maximise the induced displacement and vibration amplitude thus improving the actuation efficiency. Resonant frequencies in the MHz range have been obtained with the ring architectures therefore achieving higher frequencies compared to beam architectures. In addition, electro-thermal mixing of two input frequencies has been demonstrated and performed with the fabricated Al/SiC structures. Furthermore, piezo-electric transduction has been used for actuating the PZT/SiC cantilevers and for sensing the devices' resonance electrically. The design of the PZT piezo-electric active layer has been shown to influence strongly the devices' resonant frequency and has been optimised to enhance the electrical output by decreasing the electrodes length thus decreasing the feedthrough capacitance.The results obtained in this work can be used for the implementation of SiC MEMS mixer-filters with electro-thermal actuation and piezo-electric sensing for transceiver applications

    The Role of Attachment in Experiences of Affiliate Stigma Among Parents of Lesbian, Gay, and Bisexual Individuals

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    The purpose of this study was to examine the relationship between parents of lesbian, gay, and bisexual (LGB) individuals’ attachment styles and their experiences of LGB affiliate stigma associated with having an LGB child. It was hypothesized that higher levels of anxious and/or avoidant attachment, as measured by the Experiences in Close Relationships Scale (ECR; Brennan, Clark, & Shaver, 1998), would predict higher levels of LGB affiliate stigma, as measured by the LGB Affiliate Stigma Measure (LGB-ASM; Robinson & Brewster, 2016). A sample of 87 self-identified parents of LGB individuals completed the ECR and LGB-ASM. Utilizing multiple regression, results of statistical analyses provided partial support for the hypotheses of this study. Multiple regression analyses supported the primary hypothesis: overall, higher levels of insecure attachment predicted higher levels of LGB affiliate stigma among parents of LGB individuals. Contrary to hypothesis, however, while higher levels of anxious attachment were found to be a significant predictor of two of the three domains of LGB affiliate stigma, levels of avoidant attachment did not emerge as a significant predictor of any of the three domains of LGB affiliate stigma. Clinical implications, limitations, and directions for future research, particularly with parents of LGB individuals, are discussed

    A MEMS Filter Based on Ring Resonator with Electrothermal Actuation and Piezoelectric Sensing

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    AbstractWe report on the design of a two-port ring microelectromechanical (MEMS) resonator with electrothermal actuation and piezoelectric sensing for filtering applications. The ring resonator has been fabricated in silicon carbide with top platinum electrothermal actuator and lead zirconium titanate piezoelectric sensor. The transmission frequency response measurements have shown that the device with a ring radius of 200μm resonate in the frequency range 0.4MHz – 0.6MHz, in the presence of tuning. By applying DC bias voltage in the range 4V – 10V, a frequency tuning range of 330,000ppm has been achieved

    Ornithodoros quilinensis sp. nov. (Acari, Argasidae), a new tick species from the Chacoan region in Argentina

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    Ornithodoros quilinensis sp. nov. (Acari: Argasidae) is described from larvae collected on the small rodents Graomys centralis (Cricetidae: Sigmodontinae) in Argentina. The diagnostic characters for this new species are a combination of small size (520-540 μm), a dorsal plate oval in shape with a length of approximately 200 μm, 14 pairs of dorsal setae, hypostome short and narrower at the base (length from Ph1 to apex 133 μm (120-141)) with dental formula 2/2 and apex blunt, and the capsule of the Haller's organ irregular in shape and without reticulations. The analysis of the 16S rDNA sequences available for the genus Ornithodoros indicate that, phylogenetically, O. quilinensis represents an independent lineage only related to a Bolivian tick species of the genus Ornithodoros yet not formally described.Fil: Venzal, José M.. Universidad de la Republica, Salto; UruguayFil: Nava, Santiago. Instituto Nacional de Tecnología Agropecuaria Eea, Rafaela; ArgentinaFil: Mangold, Atilio Jose. Instituto Nacional de Tecnología Agropecuaria Eea, Rafaela; ArgentinaFil: Mastropaolo, Mariano. Instituto Nacional de Tecnología Agropecuaria Eea, Rafaela; ArgentinaFil: Casás, Gustavo. UNIVERSIDAD DE LA REPUBLICA (UDELAR); . Universidad de la República; UruguayFil: Guglielmone, Alberto Alejandro. Instituto Nacional de Tecnología Agropecuaria Eea, Rafaela; Argentin

    Nuevos registros de garrapatas (Acari: Ixodidae) asociadas a roedores sigmodontinos en Chubut, Argentina

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    Se reportan nuevos hallazgos de garrapatas obtenidas de roedores capturados en sitios cercanos a Cholila (42o31'S, 71o27'W), provincia del Chubut (Argentina). Se registraron las siguientes asociaciones parásito-hospedador: Oligoryzomys lonngicaudatus: 1 larva de Amblyomma tigrinum, 1 hembra de Ixodes sigelos, 2 ninfas de I. sigelos; Reithrodon auritus: 1 hembra de I. sigelos; Loxodontomys micropus: 1 ninfa de I. sigelos; Chelemys macronyx: 7 larvas de I. sigelos. Ixodes sigelos no ha sido reportada previamente en C. macronyx, así como tampoco A. tigrinum sobre O. longicaudatus. Estos resultados brindan nueva evidencia del rol fundamental que cumplen los roedores en el ciclo biológico de algunas garrapatas presentes en la Argentina.We report new findings of ticks from rodents trapped at different sites near Cholila (42o31’S, 71o27’W), Chubut Province (Argentina). The following host-parasite associations were recorded: Oligoryzomys longicaudatus: 1 larva of Amblyomma tigrinum, 1 female of Ixodes sigelos, 2 nymphs of I. sigelos; Reithrodon auritus: 1 female of I. sigelos; Loxodontomys micropus: 1 nymph of I. sigelos; Chelemys macronyx: 7 larvae of I. sigelos. Ixodes sigelos has not been previously reported on C. macronyx as well as not A. tigrinum on O. longicaudatus. These results provide new evidence about the fundamental role of rodents in the life cycle of some ticks present in Argentina.Fil: Mastropaolo, Mariano. Universidad Nacional del Litoral; ArgentinaFil: Martin, Gabriel Mario. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Nava, Santiago. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Santa Fe. Estacion Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
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