1,279 research outputs found

    3x3 Multibeam Network for a Triangular Array of Three Radiating Elements

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    A multibeam antenna study based on Butler network will be undertaken in this document. These antenna designs combines phase shift systems with multibeam networks to optimize multiple channel systems. The system will work at 1.7 GHz with circular polarization. Specifically, result simulations and measurements of 3 element triangular subarray will be shown. A 45 element triangular array will be formed by the subarrays. Using triangular subarrays, side lobes and crossing points are reduced

    Factors associated with overeducation among recent graduates during labour market integration: The case of Catalonia (Spain)

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    Overeducation has usually been considered a phenomenon brought about during integration into the labour market. There is no single explanation, but rather several factors that are associated with overeducation. We analyse overeducation among graduates in Catalonia four years after finishing their degrees. The analysis is based on the self-assessment made by workers in surveys conducted by AQU (Catalan University Quality Assurance Agency) between 2008 and 2014 and we use logit and probit statistical models to determine the probability of a graduate being overeducated, depending on a wide range of economic, sociological, technological and academic variables. We use the Heckman methodology in the analysis. This study corroborates the results of previous studies on the relationship between wages, job satisfaction and overeducation. In addition, the results show, firstly, differences in levels of overeducation between different fields of study, most notably between 'Humanities and Arts' and 'Health Sciences'. Secondly, the results reveal the impact of the economic cycle on overeducation. Thirdly, the variables used in the statistical model exhibit stable behaviour and, as a result, they provide an explanation for overeducation as a structural phenomenon, regardless of the economic situation. Furthermore, other variables show a significant relationship with signalling theory and career mobility theory, which both explain the overeducation phenomenon. We especially emphasise the role of professional career development during undergraduate studies. Additionally, we found that the family socio-economic environment is relevant in explaining overeducation and, lastly, technological factors and aspects of the graduates' work environment also contribute to explaining the phenomenon

    Nuevo índice para evaluar anomalías de elementos traza en suelos: el caso del SE español

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    In this work, an index is established to detect anomalies in trace elements in the soil. This index, which relates the total concentration of each element with the regional geochemical background value of the element considered, was defined by studying the levels of trace elements from different soils located in SE Spain. In the area, a previous screening of trace elements detected seven zones with anomalies and revealed two conflictive areas: Sierra Gador and Cabo de Gata. In each zone, a second sampling was undertaken at two different depths (0-20 cm and 20-40 cm). The results indicate that the main anomalies were due to arsenic (As), lead (Pb), and zinc (Zn). In Sierra Gador Pb was the element that registered the highest rate of enrichment with respect to the regional geochemical background, reaching values up to 270-fold higher in some samples. In this zone, more than 50% of the samples were anomalous in any of the trace elements studied (higher than regional geochemical background). In Cabo de Gata, As concentration was higher than the geochemical background in more than 40% of the samples; meanwhile Pb concentration was higher in 50% of the samples.En este trabajo establecemos un índice para detectar anomalías en el contenido de elementos traza en suelos. Este índice relaciona el contenido total de cada elemento traza con el fondo geoquímico regional, definido mediante el estudio de los niveles de elementos traza en diferentes suelos localizados en el sureste español. En un primer estudio sobre niveles de elementos traza en suelos del área de estudio detectaron siete zonas con anomalías, de las cuales dos fueron consideradas conflictivas: Sierra de Gádor y Cabo de Gata. En cada una de estas dos zonas se realizó un segundo estudio más exhaustivo a dos niveles de profundidad (0-20 y 20-40 cm). Los resultados indican que las principales anomalías correspondes a los niveles de As, Pb y Zn. En Sierra de Gádor el Pb es el elemento que presenta una mayor tasa de enriquecimiento con respecto al fondo geoquímico regional, con valores puntuales que lo superan hasta 270 veces. También en esta zona más del 50% de las muestras presentan anomalías en alguno de los elementos analizados. En Cabo de Gata el As supera el fondo geoquímico regional en más del 40% de las muestras; mientras que el Pb lo supera en el 50% de las muestras.This study has been made possible by the research Project no. 1550 of the Regional Environmental Department of the Andalusian Government

    Incisivo lateral superior con dos raíces y dos conductos. Caso Clínico.

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    Las anomalías en la morfología del incisivo lateral superior son de muy baja frecuencia. Las anomalías de desarrollo radicular pueden presentarse como alteraciones tanto en el número de conductos, como en el número de raíces, así como en ambas regiones a la vez. En el presente trabajo, se reporta el caso de un paciente que se presenta a la consulta con malestar en el incisivo lateral superior izquierdo. En la radiografía preoperatoria se detectó la presencia de dos conductos y dos raíces, sin anomalía morfológica de su corona clínica, con requerimiento de tratamiento endodóntico. Concluimos que una correcta interpretación de las imágenes radiográficas preoperatorias es esencial, para poder detectar estas variantes y tomar las consideraciones necesarias para el adecuado tratamiento endodóntico.Fil: Martinez, P.. Universidad de Buenos Aires. Facultad de Odontología; Argentina;Fil: Boldo, M.. Universidad de Buenos Aires. Facultad de Odontología; Argentina;Fil: Corominola, P.. Universidad de Buenos Aires. Facultad de Odontología; Argentina;Fil: Sierra, L.. Universidad de Buenos Aires. Facultad de Odontología; Argentina;Fil: Lenarduzzi, A.. Universidad de Buenos Aires. Facultad de Odontología; Argentina;Fil: Fernández Solari, Jose Javier. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Fisiología; Argentina;Fil: Rodriguez, P.. Universidad de Buenos Aires. Facultad de Odontología; Argentina

    Naturalistic driving study for older drivers based on the DriveSafe app

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    2019 IEEE Intelligent Transportation Systems Conference (ITSC), Auckland, New Zealand, 27-30 Oct. 2019Elderly population is increasing year after year in the developed countries. However, the knowledge of actual mobility needs of senior drivers is scarce. In this paper, we present a naturalistic driving study (NDS) focused on older drivers through smartphone technology and using our DriveSafe app. Our system automatically generates a driving analysis report based on objective indicators. The proposal supposes an improvement over the traditional surveys and observers, and represents an advance over the current NDSs by using smartphones instead of complex instrumented vehicles. Our method avoids the problems of manual annotation by using an automatic method for data reduction information. Furthermore, a comparison between traditional questionnaires and information provided by our system is carried out and conclusions are presented.Ministerio de Economía y CompetitividadDGTComunidad de Madri

    Glucocorticoid receptor dysregulation underlies 5-HT2AR-dependent synaptic and behavioral deficits in a mouse neurodevelopmental disorder model.

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    Prenatal environmental insults increase the risk of neurodevelopmental psychiatric conditions in the offspring. Structural modifications of dendritic spines are central to brain development and plasticity. Using maternal immune activation (MIA) as a rodent model of prenatal environmental insult, previous results have reported dendritic structural deficits in the frontal cortex. However, very little is known about the molecular mechanism underlying MIA-induced synaptic structural alterations in the offspring. Using prenatal (E12.5) injection with polyinosinic-polycytidylic acid potassium salt as a mouse MIA model, we show here that upregulation of the serotonin 5-HT2A receptor (5-HT2AR) is at least in part responsible for some of the effects of prenatal insults on frontal cortex dendritic spine structure and sensorimotor gating processes. Mechanistically, we report that this upregulation of frontal cortex 5-HT2AR expression is associated with MIA-induced reduction of nuclear translocation of the glucocorticoid receptor (GR) and, consequently, a decrease in the enrichment of GR at the 5-HT2AR promoter. The translational significance of these preclinical findings is supported by data in postmortem human brain samples suggesting dysregulation of GR translocation in frontal cortex of schizophrenia subjects. We also found that repeated corticosterone administration augmented frontal cortex 5-HT2AR expression and reduced GR binding to the 5-HT2AR promoter. However, virally (adeno-associated virus) mediated augmentation of GR function reduced frontal cortex 5-HT2AR expression and improved sensorimotor gating processes via 5-HT2AR. Together, these data support a negative regulatory relationship between GR signaling and 5-HT2AR expression in the mouse frontal cortex that may carry implications for the pathophysiology underlying 5-HT2AR dysregulation in neurodevelopmental psychiatric disorders.National Institutes of Health R01MH084894 (to J. G.-M.), R01MH111940 (to J. G.-M.), NIH-N01DA-17-8932 (to P. M. B.), NIH-N01DA-19-8949 (to P. M. B.), and F30MH116550 (to J. M. S.), and Basque Government IT1211-19 (to J. J. M.) participated in the funding of this study. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health
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