997 resultados para Perceptual knowledge
Resumo:
In this paper, we describe several techniques for detecting tonic pitch value in Indian classical music. In Indian music, the raga is the basic melodic framework and it is built on the tonic. Tonic detection is therefore fundamental for any melodic analysis in Indian classical music. This workexplores detection of tonic by processing the pitch histograms of Indian classic music. Processing of pitch histograms using group delay functions and its ability to amplify certain traits of Indian music in the pitch histogram, is discussed. Three different strategies to detect tonic, namely, the concert method, the template matching and segmented histogram method are proposed. The concert method exploits the fact that the tonic is constant over a piece/concert.templatematchingmethod and segmented histogrammethodsuse the properties: (i) the tonic is always present in the background, (ii) some notes are less inflected and dominant, to detect the tonic of individual pieces. All the three methods yield good results for Carnatic music (90−100% accuracy), while for Hindustanimusic, the templatemethod works best, provided the v¯adi samv¯adi notes for a given piece are known (85%).
Resumo:
ViralZone (http://viralzone.expasy.org) is a knowledge repository that allows users to learn about viruses including their virion structure, replication cycle and host-virus interactions. The information is divided into viral fact sheets that describe virion shape, molecular biology and epidemiology for each viral genus, with links to the corresponding annotated proteomes of UniProtKB. Each viral genus page contains detailed illustrations, text and PubMed references. This new update provides a linked view of viral molecular biology through 133 new viral ontology pages that describe common steps of viral replication cycles shared by several viral genera. This viral cell-cycle ontology is also represented in UniProtKB in the form of annotated keywords. In this way, users can navigate from the description of a replication-cycle event, to the viral genus concerned, and the associated UniProtKB protein records.
Resumo:
A fundamental trait of the human self is its continuum experience of space and time. Perceptual aberrations of this spatial and temporal continuity is a major characteristic of schizophrenia spectrum disturbances--including schizophrenia, schizotypal personality disorder and schizotypy. We have previously found the classical Perceptual Aberration Scale (PAS) scores, related to body and space, to be positively correlated with both behavior and temporo-parietal activation in healthy participants performing a task involving self-projection in space. However, not much is known about the relationship between temporal perceptual aberration, behavior and brain activity. To this aim, we composed a temporal Perceptual Aberration Scale (tPAS) similar to the traditional PAS. Testing on 170 participants suggested similar performance for PAS and tPAS. We then correlated tPAS and PAS scores to participants' performance and neural activity in a task of self-projection in time. tPAS scores correlated positively with reaction times across task conditions, as did PAS scores. Evoked potential mapping and electrical neuroimaging showed self-projection in time to recruit a network of brain regions at the left anterior temporal cortex, right temporo-parietal junction, and occipito-temporal cortex, and duration of activation in this network positively correlated with tPAS and PAS scores. These data demonstrate that schizotypal perceptual aberrations of both time and space, as reflected by tPAS and PAS scores, are positively correlated with performance and brain activation during self-projection in time in healthy individuals along the schizophrenia spectrum.
Resumo:
In a previous work we have shown that sinusoidal whole-body rotations producing continuous vestibular stimulation, affected the timing of motor responses as assessed with a paced finger tapping (PFT) task (Binetti et al. (2010). Neuropsychologia, 48(6), 1842-1852). Here, in two new psychophysical experiments, one purely perceptual and one with both sensory and motor components, we explored the relationship between body motion/vestibular stimulation and perceived timing of acoustic events. In experiment 1, participants were required to discriminate sequences of acoustic tones endowed with different degrees of acceleration or deceleration. In this experiment we found that a tone sequence presented during acceleratory whole-body rotations required a progressive increase in rate in order to be considered temporally regular, consistent with the idea of an increase in "clock" frequency and of an overestimation of time. In experiment 2 participants produced self-paced taps, which entailed an acoustic feedback. We found that tapping frequency in this task was affected by periodic motion by means of anticipatory and congruent (in-phase) fluctuations irrespective of the self-generated sensory feedback. On the other hand, synchronizing taps to an external rhythm determined a completely opposite modulation (delayed/counter-phase). Overall this study shows that body displacements "remap" our metric of time, affecting not only motor output but also sensory input.
Resumo:
R. solanacearum was ranked in a recent survey the second most important bacterial plant pathogen, following the widely used research model Pseudomonas syringae (Mansfield et al., 2012). The main reason is that bacterial wilt caused by R. solanacearum is the world"s most devastating bacterial plant disease (http://faostat.fao.org), threatening food safety in tropical and subtropical agriculture, especially in China, Bangladesh, Bolivia and Uganda (Martin and French, 1985). This is due to the unusually wide host range of the bacterium, its high persistence and because resistant crop varieties are unavailable. In addition, R. solanacearum has been established as a model bacterium for plant pathology thanks to pioneering molecular and genomic studies (Boucher et al., 1985; Cunnac et al., 2004b; Mukaihara et al., 2010; Occhialini et al., 2005; Salanoubat et al., 2002). As for many bacterial pathogens, the main virulence determinant in R. solanacearum is the type III secretion system (T3SS) (Boucher et al., 1994), which injects a number of effector proteins into plant cells causing disease in hosts or an hypersensitive response in resistant plants. In this article we discuss the current state in the study of the R. solanacearum T3SS, stressing the latest findings and future perspectives.
Resumo:
In this paper I present an endogenous growth model where the engine of growth is in-house R&D performed by high-tech firms. I model knowledge (patent) licensing among high-tech firms. I show that if there is knowledge licensing, high-tech firms innovate more and economic growth is higher than in cases when there are knowledge spillovers or there is no exchange of knowledge among high-tech firms. However, in case when there is knowledge licensing the number of high-tech firms is lower than in cases when there are knowledge spillovers or there is no exchange of knowledge.