74 research outputs found

    Preliminary results of the small animal rotational positron emisson tomography scanner

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    [Abstract] AMI Annual Conference 2004, March 27-31, Orlando, FloridaThis contribution reports preliminary results of a high-resolution small animal positron emission tomography (PET) based on pairs of opposed scintillation rotating detectors working in time coincidencePublicad

    Análisis de la acción tutorial en ingeniería y arquitectura. Gestión eficaz del tiempo

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    En este trabajo expondremos un análisis exhaustivo de como se ha desarrollado la acción tutorial en la Escuela Politécnica Superior de la Universidad de Alicante en el curso 2014/2015. El marcado carácter de voluntariedad de la acción tutorial en nuestro centro por parte de estudiantes y tutores permite que el trabajo se realice más satisfactoriamente tanto por parte de tutores como por parte de los estudiantes, puesto que han decidido seguir el plan por ello mismos y no como una imposición. Además expondremos nuestras experiencias en el desarrollo del Taller de Gestión Eficaz del Tiempo, taller desarrollado en nuestro centro bajo la tutela de la experta Nuria Alberquilla, que tiene entre otros muchos objetivos el aprendizaje y puesta en práctica de técnicas para realizar una gestión eficaz del tiempo, con un mejor equilibrio entre la vida académica y personal y la identificación de los principales factores externos e internos que influyen en los resultados obtenidos, y cómo mejorarlos

    Experiencias en la tutorización de enseñanzas técnicas

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    El PAT en la Escuela Politécnica está abierto a todos aquellos tutores que deseen formar parte del plan y también a todos los alumnos, que, voluntariamente pueden marcar la opción de participar en el plan en la matrícula, y también a aquellos que, a pesar de no marcar la opción en la matrícula, finalmente han decidido seguir el plan de acción tutorial. Esta característica de participación e inscripción voluntaria permite que el trabajo se realice más satisfactoriamente tanto por parte de tutores como por parte de los alumnos, puesto que han decidido seguir el plan por ello mismos y no como una imposición. Con este trabajo nos proponemos presentar nuestras experiencias en el desarrollo de la tutorización de nuestros estudiantes así como la evolución en el desarrollo de la tutorización por pares

    Coordinación del Plan de Acción Tutorial en la Escuela Politécnica Superior

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    Al igual que en cursos anteriores en la Escuela Politécnica se desarrolla, promovido por el Vicerrectorado de Estudios, Formación y Calidad, coordinado desde el Instituto de Ciencias de la Educación, el Plan de Acción Tutorial (PAT) el cual está abierto a todos aquellos tutores que deseen formar parte del plan y también a todos los estudiantes, que, voluntariamente pueden marcar la opción de participar en el plan en la matrícula, y también a aquellos que, a pesar de no marcar la opción en la matrícula, finalmente han decidido seguir el plan de acción tutorial. Esta característica de participación e inscripción voluntaria permite que el trabajo se realice más satisfactoriamente tanto por parte de tutores como por parte de los estudiantes, puesto que han decidido seguir el plan por ello mismos y no como una imposición. Con este resumen nos proponemos presentar nuestras experiencias en el desarrollo del PAT de nuestro centro

    Identification of Brucella by MALDI-TOF Mass Spectrometry. Fast and Reliable Identification from Agar Plates and Blood Cultures

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    BACKGROUND: MALDI-TOF mass spectrometry (MS) is a reliable method for bacteria identification. Some databases used for this purpose lack reference profiles for Brucella species, which is still an important pathogen in wide areas around the world. We report the creation of profiles for MALDI-TOF Biotyper 2.0 database (Bruker Daltonics, Germany) and their usefulness for identifying brucellae from culture plates and blood cultures. METHODOLOGY/PRINCIPAL FINDINGS: We created MALDI Biotyper 2.0 profiles for type strains belonging to B. melitensis biotypes 1, 2 and 3; B. abortus biotypes 1, 2, 5 and 9; B. suis, B. canis, B ceti and B. pinnipedialis. Then, 131 clinical isolates grown on plate cultures were used in triplicate to check identification. Identification at genus level was always correct, although in most cases the three replicates reported different identification at species level. Simulated blood cultures were performed with type strains belonging to the main human pathogenic species (B. melitensis, B. abortus, B. suis and B. canis), and studied by MALDI-TOF MS in triplicate. Identification at genus level was always correct. CONCLUSIONS/SIGNIFICANCE: MALDI-TOF MS is reliable for Brucella identification to the genus level from culture plates and directly from blood culture bottles

    Counteranion-Dependent Reaction Pathways in the Protonation of Cationic Ruthenium−Vinylidene Complexes

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    The tetraphenylborate salts of the cationic vinylidene complexes [Cp*Ru=C=CHR(iPr2PNHPy)]+ (R = p-C6H4CF3 (1a-BPh4), Ph (1b-BPh4), p-C6H4CH3 (1c- BPh4), p-C6H4Br (1d-BPh4), tBu (1e-BPh4), H (1f-BPh4)) have been protonated using an excess of HBF4·OEt2 in CD2Cl2, furnishing the dicationic carbyne complexes [Cp*Ru≡CCH2R(iPr2PNHPy)]2+ (R = p-C6H4CF3 (2a), Ph (2b), p-C6H4CH3 (2c), p-C6H4Br (2d), tBu (2e), H (2f)), which were characterized in solution at low temperature by NMR spectroscopy. The corresponding reaction of the chloride salts 1a-Cl, 1b-Cl, 1c-Cl, and 1d-Cl followed a different pathway, instead affording the novel alkene complexes [Cp*RuCl(κ1(N),η2(C,C)-C5H4N-NHPiPr2CH=CHR)][BF4] (3a−d). In these species, the entering proton is located at the α- carbon atom of the former vinylidene ligand, which also forms a P−C bond with the phosphorus atom of the iPr2PNHPy ligand. To shed light on the reaction mechanism, DFT calculations have been performed by considering several protonation sites. The computational results suggest metal protonation followed by insertion. The coordination of chloride to ruthenium leads to alkenyl species which can undergo a P−C coupling to yield the corresponding alkene complexes. The noncoordinating nature of [BPh4]− does not allow the stabilization of the unsaturated species coming from the insertion step, thus preventing this alternative pathway

    Multicenter study of brain volume abnormalities in children and adolescent-onset psychosis

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    The goal of the study is to determine the extent of structural brain abnormalities in a multicenter sample of children and adolescents with a recent-onset first episode of psychosis (FEP), compared with a sample of healthy controls. Total brain and lobar volumes and those of gray matter (GM), white matter, and cerebrospinal fluid (CSF) were measured in 92 patients with a FEP and in 94 controls, matched for age, gender, and years of education. Male patients (n = 64) showed several significant differences when compared with controls (n = 61). GM volume in male patients was reduced in the whole brain and in frontal and parietal lobes compared with controls. Total CSF volume and frontal, temporal, and right parietal CSF volumes were also increased in male patients. Within patients, those with a further diagnosis of "schizophrenia" or "other psychosis" showed a pattern similar to the group of all patients relative to controls. However, bipolar patients showed fewer differences relative to controls. In female patients, only the schizophrenia group showed differences relative to controls, in frontal CSF. GM deficit in male patients with a first episode correlated with negative symptoms. Our study suggests that at least part of the GM deficit in children and adolescent-onset schizophrenia and in other psychosis occurs before onset of the first positive symptoms and that, contrary to what has been shown in children-onset schizophrenia, frontal GM deficits are probably present from the first appearance of positive symptoms in children and adolescents

    Activation of Copper Species on Carbon Nitride for Enhanced Activity in the Arylation of Amines

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    We report the promoting effect of graphitic carbon nitride in Cu-catalyzed N-arylation. The abundance of pyridinic coordination sites in this host permits the adsorption of copper iodide from the reaction medium. The key to achieving high activity is to confine active Cu species on the surface, which is accomplished by introducing atomically-dispersed metal dopants to block diffusion into the bulk. The alternative route of incorporating metal during the synthesis of graphitic carbon nitride is ineffective as Cu is thermodynamically more stable in inactive subsurface positions. A combination of X-ray absorption, X-ray photoelectron, and electron paramagnetic resonance spectroscopy, density functional theory, and Kinetic Monte Carlo simulations is employed to determine the location and associated geometry as well as the electronic structure of metal centers. N-arylation activity correlates to the surface coverage by copper, which varies during the reaction due to an interplay between site formation via adsorption from the reaction medium and deactivation by diffusion into the bulk of the material, and is highest when an Fe dopant is used that hinders movement through the lattice

    Counteranion and Solvent Assistance in Ruthenium-Mediated Alkyne to Vinylidene Isomerizations

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    The complex [Cp*RuCl(iPr2PNHPy)] (1) reacts with 1-alkynes HC≡CR (R = COOMe, C6H4CF3) in dichloromethane furnishing the corresponding vinylidene complexes [Cp*Ru≡C≡CHR(iPr2PNHPy)]Cl (R = COOMe (2a- Cl), C6H4CF3 (2b-Cl)), whereas reaction of 1 with NaBPh4 in MeOH followed by addition of HC≡CR (R = COOMe, C6H4CF3) yields the metastable π-alkyne complexes [Cp*Ru(η2-HC≡CR)(iPr2PNHPy)][BPh4] (R = COOMe (3a-BPh4), C6H4CF3 (3b-BPh4)). The transformation of 3a-BPh4/3b-BPh4 into their respective vinylidene isomers in dichloromethane is very slow and requires hours to its completion. However, this process is accelerated by addition of LiCl in methanol solution. Reaction of 1 with HC≡CR (R = COOMe, C6H4CF3) in MeOH goes through the intermediacy of the π-alkyne complexes [Cp*Ru(η2-HC≡CR)(iPr2PNHPy)]Cl (R = COOMe (3a-Cl), C6H4CF3 (3b-Cl)), which rearrange to vinylidenes in minutes, i.e., much faster than their counterparts containing the [BPh4]− anion. The kinetics of these isomerizations has been studied in solution by NMR. With the help of DFT studies, these observations have been interpreted in terms of chloride- and methanolassisted hydrogen migrations. Calculations suggest participation of a hydrido−alkynyl intermediate in the process, in which the hydrogen atom can be transferred from the metal to the β-carbon by means of species with weak basic character acting as proton shuttles

    Imigração e saúde: a (in)acessibilidade das mulheres imigrantes aos cuidados de saúde

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    A utilização dos serviços de saúde pelas populações imigrantes tem vindo a ser considerado um dos mais importantes indicadores da sua integração nas so- ciedades receptoras (Dias e col., 2009). No entanto, o conhecimento em torno da qualidade e da eficácia do acesso dos/as imigrantes aos cuidados de saúde, especialmente no que respeita às mulheres imigran- tes, é ainda escasso em Portugal (Fonseca e col., 2005). Embora os estudos nacionais tenham vindo, nas últimas décadas, a procurar traçar os diferentes perfis sociais das mulheres imigrantes em Portugal, sobretudo no que concerne às suas relações fami- liares ou laborais (Wall e col., 2005), a investigação no domínio da saúde é ainda parca e exclusora de uma análise centrada no género ou interseccional. Neste texto apresenta-se uma reflexão sobre os de- terminantes que condicionam a (in)acessibilidade das mulheres imigrantes aos cuidados de saúde, enfatizando-se os fatores que poderão estar a agir no sentido contrário à sua integração neste setor
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