88 research outputs found

    Problems in Defining a Prototypical Transitive Sentence Typologically

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    High Frequency Thick Film BST Ferroelectric Phase Shifter

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    This paper discusses the performance of a thick-film ferroelectric phase shifter at high frequency. The phase shifter is fabricated from Barium Strontium Titanate (BST) thick-films on alumina substrates using a screen-printing method, and the electrodes are patterned using direct gravure-printing. We have achieved down to 40 μm gaps between electrodes using this method. Comparison between the theoretical response and experiment results will be presented. The extracted dielectric constants of the BST material using this phase shifter is also be presented here

    Dendritic Spikes Amplify the Synaptic Signal to Enhance Detection of Motion in a Simulation of the Direction-Selective Ganglion Cell

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    The On-Off direction-selective ganglion cell (DSGC) in mammalian retinas responds most strongly to a stimulus moving in a specific direction. The DSGC initiates spikes in its dendritic tree, which are thought to propagate to the soma with high probability. Both dendritic and somatic spikes in the DSGC display strong directional tuning, whereas somatic PSPs (postsynaptic potentials) are only weakly directional, indicating that spike generation includes marked enhancement of the directional signal. We used a realistic computational model based on anatomical and physiological measurements to determine the source of the enhancement. Our results indicate that the DSGC dendritic tree is partitioned into separate electrotonic regions, each summing its local excitatory and inhibitory synaptic inputs to initiate spikes. Within each local region the local spike threshold nonlinearly amplifies the preferred response over the null response on the basis of PSP amplitude. Using inhibitory conductances previously measured in DSGCs, the simulation results showed that inhibition is only sufficient to prevent spike initiation and cannot affect spike propagation. Therefore, inhibition will only act locally within the dendritic arbor. We identified the role of three mechanisms that generate directional selectivity (DS) in the local dendritic regions. First, a mechanism for DS intrinsic to the dendritic structure of the DSGC enhances DS on the null side of the cell's dendritic tree and weakens it on the preferred side. Second, spatially offset postsynaptic inhibition generates robust DS in the isolated dendritic tips but weak DS near the soma. Third, presynaptic DS is apparently necessary because it is more robust across the dendritic tree. The pre- and postsynaptic mechanisms together can overcome the local intrinsic DS. These local dendritic mechanisms can perform independent nonlinear computations to make a decision, and there could be analogous mechanisms within cortical circuitry

    Susceptibility of low-density lipoprotein particles to aggregate depends on particle lipidome, ismodifiable, and associates with future cardiovascular deaths

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    Aims Low-density lipoprotein (LDL) particles cause atherosclerotic cardiovascular disease (ASCVD) through their retention, modification, and accumulation within the arterial intima. High plasma concentrations of LDL drive this disease, but LDL quality may also contribute. Here, we focused on the intrinsic propensity of LDL to aggregate upon modification. We examined whether inter-individual differences in this quality are linked with LDL lipid composition and coronary artery disease (CAD) death, and basic mechanisms for plaque growth and destabilization.Methods and results We developed a novel, reproducible method to assess the susceptibility of LDL particles to aggregate during lipolysis induced ex vivo by human recombinant secretory sphingomyelinase. Among patients with an established CAD, we found that the presence of aggregation-prone LDL was predictive of future cardiovascular deaths, independently of conventional risk factors. Aggregation-prone LDL contained more sphingolipids and less phosphatidylcholines than did aggregation-resistant LDL. Three interventions in animal models to rationally alter LDL composition lowered its susceptibility to aggregate and slowed atherosclerosis. Similar compositional changes induced in humans by PCSK9 inhibition or healthy diet also lowered LDL aggregation susceptibility. Aggregated LDL in vitro activated macrophages and T cells, two key cell types involved in plaque progression and rupture.Conclusion Our results identify the susceptibility of LDL to aggregate as a novel measurable and modifiable factor in the progression of human ASCVD

    Folklore as an evidential category

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    Folklore refers to information that we have learnt as a part of the history of our own people and that has passed on from generation to generation for hundreds, or even thousands of years. This paper shows that as an information source folklore has features in common with other information sources, most notably hearsay, but it nevertheless constitutes an information source of its own, characterized as [-personal] [-direct] and [+internalized]. In addition, the paper proposes a formal-functional typology based on the element used for folklore coding. It is also shown that the semantic similarity of the coded element with the proposed definition of folklore corresponds to its frequency. Finally, the paper discusses the central theoretical implications this study has for our understanding of evidentiality.Peer reviewe

    Problems in Defining a Prototypical Transitive Sentence Typologically

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    Enfocament comunicatiu i ensenyament de llengües: una aplicació en un centre multicultural

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    [cat] És innegable que el sorgiment de l’enfocament comunicatiu va canviar la forma d’ensenyar llengua en un moment en què la visió formalista era imperant. Malgrat això, aquesta metodologia encara no s’ha estès entre els centres de secundària del nostre entorn més proper i, com a conseqüència, es pot observar com els estudiants presenten serioses mancances en la competència lingüística. Partint d’aquest situació, es presenta aquest treball amb la intenció de proposar una unitat didàctica que pugui obrir un camí per millorar l’ensenyament de la llengua a l’educació secundària. La proposta que es presenta beu de l’enfocament comunicatiu però deixa enrere el model més clàssic d’aquesta metodologia i incorpora l’ensenyament de la gramàtica, ja que s’ha demostrat la seva eficàcia a l’hora d’aprendre llengües. Aquesta aportació no és gaire innovadora en relació amb les metodologies o activitats emprades, però tampoc és la intenció. De fet, la idea inicial ha estat poder dissenyar una unitat didàctica que millori el rendiment i l’aprenentatge significatiu dels alumnes a partir d’una base teòrica que ja s’ha demostrat eficaç
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