906 resultados para Agregação temporal


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We analysed the relationship between changes in land cover patterns and the Eurasian otter occurrence over the course of about 20 years (1985-2006) using multi-temporal Species Distribution Models (SDMs). The study area includes five river catchments covering most of the otter's Italian range. Land cover and topographic data were used as proxies of the ecological requirements of the otter within a 300-m buffer around river courses. We used species presence, pseudo-absence data, and environmental predictors to build past (1985) and current (2006) SDMs by applying an ensemble procedure through the BIOMOD modelling package. The performance of each model was evaluated by measuring the area under the curve (AUC) of the receiver-operating characteristic (ROC). Multi-temporal analyses of species distribution and land cover maps were performed by comparing the maps produced for 1985 and 2006. The ensemble procedure provided a good overall modelling accuracy, revealing that elevation and slope affected the otter's distribution in the past; in contrast, land cover predictors, such as cultivations and forests, were more important in the present period. During the transition period, 20.5% of the area became suitable, with 76% of the new otter presence data being located in these newly available areas. The multi-temporal analysis suggested that the quality of otter habitat improved in the last 20 years owing to the expansion of forests and to the reduction of cultivated fields in riparian belts. The evidence presented here stresses the great potential of riverine habitat restoration and environmental management for the future expansion of the otter in Italy

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Recent evidence suggests the human auditory system is organized,like the visual system, into a ventral 'what' pathway, devoted toidentifying objects and a dorsal 'where' pathway devoted to thelocalization of objects in space w1x. Several brain regions have beenidentified in these two different pathways, but until now little isknown about the temporal dynamics of these regions. We investigatedthis issue using 128-channel auditory evoked potentials(AEPs).Stimuli were stationary sounds created by varying interaural timedifferences and environmental real recorded sounds. Stimuli ofeach condition (localization, recognition) were presented throughearphones in a blocked design, while subjects determined theirposition or meaning, respectively.AEPs were analyzed in terms of their topographical scalp potentialdistributions (segmentation maps) and underlying neuronalgenerators (source estimation) w2x.Fourteen scalp potential distributions (maps) best explained theentire data set.Ten maps were nonspecific (associated with auditory stimulationin general), two were specific for sound localization and two werespecific for sound recognition (P-values ranging from 0.02 to0.045).Condition-specific maps appeared at two distinct time periods:;200 ms and ;375-550 ms post-stimulus.The brain sources associated with the maps specific for soundlocalization were mainly situated in the inferior frontal cortices,confirming previous findings w3x. The sources associated withsound recognition were predominantly located in the temporal cortices,with a weaker activation in the frontal cortex.The data show that sound localization and sound recognitionengage different brain networks that are apparent at two distincttime periods.References1. Maeder et al. Neuroimage 2001.2. Michel et al. Brain Research Review 2001.3. Ducommun et al. Neuroimage 2002.

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In a medieval Barcelonan side-street, urine, rubbish, and a bewildering array of graphic imagery splatters the narrowing walls between two major thoroughfares. A contemporary conflict between residents, unknown artists and others is played out using banners, bottles, stickers, posters, stencils, spray paint, and bodily substances. In this shadowed liminality, local and global debates are superimposed upon substructures constructed from disease, prostitution, and the Saint of the Plague. The continuing urban struggle constitutes temporal statements of dirt and purity, violence and humour, dominance and resistance, death and salvation. Like the renovated facades masking the crumbling remains of structures long neglected, the government’s literal whitewashing of the art is a temporal cover-up of a discursive symptom stretching from deeply embedded preconditions. However, from his niche in the angular bend of the alley bearing his name, the statue of St. Rock remains unblinkingly staring, raised above the contestations expressed below.

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Accurate perception of the temporal order of sensory events is a prerequisite in numerous functions ranging from language comprehension to motor coordination. We investigated the spatio-temporal brain dynamics of auditory temporal order judgment (aTOJ) using electrical neuroimaging analyses of auditory evoked potentials (AEPs) recorded while participants completed a near-threshold task requiring spatial discrimination of left-right and right-left sound sequences. AEPs to sound pairs modulated topographically as a function of aTOJ accuracy over the 39-77ms post-stimulus period, indicating the engagement of distinct configurations of brain networks during early auditory processing stages. Source estimations revealed that accurate and inaccurate performance were linked to bilateral posterior sylvian regions activity (PSR). However, activity within left, but not right, PSR predicted behavioral performance suggesting that left PSR activity during early encoding phases of pairs of auditory spatial stimuli appears critical for the perception of their order of occurrence. Correlation analyses of source estimations further revealed that activity between left and right PSR was significantly correlated in the inaccurate but not accurate condition, indicating that aTOJ accuracy depends on the functional decoupling between homotopic PSR areas. These results support a model of temporal order processing wherein behaviorally relevant temporal information--i.e. a temporal 'stamp'--is extracted within the early stages of cortical processes within left PSR but critically modulated by inputs from right PSR. We discuss our results with regard to current models of temporal of temporal order processing, namely gating and latency mechanisms.

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O objetivo deste trabalho foi determinar os índices de captura de Rhynchophorus palmarum em armadilhas iscadas com o feromônio de agregação, 6-metil-2(E)-hepten-4-ol (rincoforol), associado a toletes de cana-de-açúcar, a pedaços de frutos do abacaxi e a seis compostos voláteis isolados de frutos do abacaxi. Os compostos voláteis do abacaxi são caracterizados por uma mistura de ésteres metílicos e etílicos, sendo o octanoato de metila e o octanoato de etila os mais abundantes. As armadilhas iscadas com o rincoforol associado a toletes de cana-de-açúcar e as iscas com rincoforol associado a pedaços de abacaxi não apresentaram diferenças significativas no número de besouros capturados. No entanto, ambas apresentaram índices de captura superiores àquelas em que o rincoforol foi utilizado em associação com voláteis do abacaxi. Não se observaram efeitos significativos do local e época de captura, nem no número de machos e de fêmeas capturados.

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En aquest treball s’ha estudiat la variabilitat temporal i espacial en l’acumulació de sediment fi a la llera del riu Isàbena (Conca de l’Ebre) al llarg d’un any (1 de Juny de 2007 al 31 de maig de 2008) així com la seva relació amb l’arribada de sediments a l’embassament de Barasona, amb el mètode directe de camp, en aquest cas el cilindre de resuspensió. Aquesta tècnica s’ha aplicat a quatre seccions ubicades al tram baix de l’Isàbena. Amb les dades obtingudes, s’ha analitzat la dinàmica de les acumulacions a les diferents estacions de l’any, tractant de trobar patrons característics.

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São apresentados resultados pertinentes às culturas do milho (Z. mays), feijão (P. vulgaris) e caupi (V. unguiculata) consorciados com bananeira 'Terra' (Musa AAB) em Teolândia, Litoral Sul da Bahia, em cultivo simultâneo, no estabelecimento da bananeira e sucessivo logo após a colheita do primeiro. Os espaçamentos utilizados foram o 4,0 x 2,0 x 3,0 m, 4,0 x 2,0 x 2,6m e 4,0 x 2,0 x 2,8m em fileira dupla, o que permitiu melhor proveito da área pelas culturas intercalares. O milho, ou o feijão, ou o caupi ocupou apenas as ruas entre as fileiras duplas de bananeiras, ficando livres as ruas formadas pelas fileiras duplas, devido ao seu sombreamento pela bananeira ser mais rápido. O objetivo deste trabalho foi avaliar o desempenho das culturas do milho, feijão e caupi na agregação de valor à bananeira 'Terra', quando consorciadas com esta cultura. Nos melhores tratamentos (T9, T6, T8 e T4), o índice de rentabilidade-IR (receita total ÷ custos) alcançou valores expressivos, de 3,36 até 6,68, resultando em efeitos altamente positivos em decorrência das tecnologias e insumos utilizados, o que vai permitir a agregação de um elevado valor à bananeira e, conseqüentemente, uma boa remuneração ao produtor. Estes resultados indicam que, para cada real investido, houve um retorno de R$ 3,36 e R$ 6,68, respectivamente. O IR 0,91 (T2), relativo à cultura do milho, implica que houve prejuízo, o que significa que a receita líquida deste tratamento vai reduzir e não incrementar a receita líquida proporcionada pela cultura da bananeira.

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The concept of temporal 'plus' epilepsy (T+E) is not new, and a number of observations made by means of intracerebral electrodes have illustrated the complexity of neuronal circuits that involve the temporal lobe. The term T+E was used to unify and better individualize these specific forms of multilobar epilepsies, which are characterized by electroclinical features primarily suggestive of temporal lobe epilepsy, MRI findings that are either unremarkable or show signs of hippocampal sclerosis, and intracranial recordings which demonstrate that seizures arise from a complex epileptogenic network including a combination of brain regions located within the temporal lobe and over closed neighbouring structures such as the orbitofrontal cortex, the insulo-opercular region, and the temporo-parieto-occipital junction. We will review here how the term of T+E has emerged, what it means, and which practical consideration it raises.

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Seizures can be an early symptom of Alzheimer's disease (AD) and can precede cognitive decline. Early epilepsy in AD can mimic transient epileptic amnesic syndrome (TEAS) or epileptic amnesic syndrome. We report the case of a patient who started a cerebrospinal fluid (CSF)-proven AD with partial seizures and TEAS that secondarily became a cortical posterior atrophy syndrome. CSF biomarkers showed a high amyloid production, amyloidopathy, and high level of total tau and p-Tau. This observation adds data to the complex AD-early epilepsy interactions and illustrates that atypical AD can cause a TEAS. Possible red flags for an underlying neurodegenerative process in TEAS are discussed.