Wyniki wyszukiwania - Biblioteka Nauki

1

The effect of carbachol on the phase of free-running locomotor activity rhythm under constant darkness (DD) and constant light (LL) in mice

100%

Gaweda M.

Folia Biologica

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1998

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tom 46

202-213

EN

Carbachol chronically and peripherally administered, depending on the circadian time, caused a phase shift in the free-running locomotor activity rhythm, resynchronized the rhythm, or had a masking effect of this rhythm in mice. In the discussion it is stressed that the drug affects the rhythmicity of this activity, probably by acting on the mechanism of suprachiasmatic nuclei.

2

Cortical synchronization suggests neural principles of visual feature grouping

100%

Eckhorn R.

Acta Neurobiologiae Experimentalis

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2000

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tom 60

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nr 2

261-269

EN

Compositions of visual scenes are related here to neural signals in visual cortex and to cortical circuit models to understand neural mechanisms of perceptual feature grouping. Starting from the hypothesis that synchronization and decoupling of cortical gamma-activities (35-90 Hz) define the relations among visual objects, we concentrate on synchronization related to (1) static retinal stimulation during ocular fixation, and (2) transient stimulation by sudden shifts in object position. The synchronization hypothesis has been tested by analyzing signal correlations in visual cortex of monkeys with the following results: Static retinal stimuli induce loosely phase-coupled gamma-activities among neurons of an object's cortical representation. Patches of gamma-synchronization become decoupled across the representation of an object's contour, and therby can code figure-ground segregation. Transient stimuli evoke synchronized volleys of stimulus-locked activities that are typically non-rhythmic and include low frequency components in addition to those in the gamma-range. It is argued that stimulus-induced and stimulus-locked synchronizations may play different roles in perceptual feature grouping.

3

SYNCHRONIZATION OF CAPACITATED VEHICLE ROUTING PROBLEM AMONG PERIODS

100%

Pekár J. , Brezina I. , Čičková z.

Ekonomický časopis (Journal of Economics)

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2017

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tom 65

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nr 1

66 – 78

EN

The routing problems are one of the most important problems in the field of logistic with great practical applicability. This article deals with synchronized distribution during time periods. It is based on optimization using classical capacitated vehicle routing problem while providing different customers’ demands among time periods. The goal is, except the minimization of the total distance, to achieve the stability of solution among the time periods, which contributes to simplification of transportation planning. Although using of the presented model can lead to a partial increase of distribution cost, on the other hand it ensures more transparent routes and eliminates the need for daily optimization. Therefore it brings a positive effect for distributors, drivers and customers that may result in greater economic benefits than the benefit from the optimization on a daily basis.

4

DETECTING BUSINESS CYCLES AND CONCORDANCE OF THE DEMAND-BASED CLASSIFIED PRODUCTION OF THE VISEGRAD COUNTRIES – REGIME SWITCHING APPROACH

100%

Štiblárová Ľ. , Siničáková M.

Ekonomický časopis (Journal of Economics)

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2017

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tom 65

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nr 10

899 – 917

EN

The aim of this paper is to detect business cycles of the Visegrad countries using Markov-switching approach and to examine their synchronicity with the Euro Area aggregate as one of the inevitable conditions for optimal common monetary policy implementation. Unlike previous studies, we provide a further analysis by the use of disaggregated data in order to achieve a detailed look at the co-movement of the production and find the highest level of the synchronization within the capital and intermediate goods sector. On the contrary, non-durable consumer goods production can be identified as a potential demand-based source of the asymmetric shocks due to the lowest rate of concordance. The results on the aggregated level complemented with the Hodrick-Prescott filtered data suggest a medium-to-high level of synchronization, although its increase in time cannot be confirmed for all Visegrad countries.

5

Reduced degree of long-range phase synchrony in pathological human brain

75%

Bhattacharya J.

Acta Neurobiologiae Experimentalis

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2001

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tom 61

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nr 4

309-318

EN

In this paper multivariate spontaneous EEG signals from three broad groups of human subjects - control, seizure, and mania - were studied with the aim of investigating the possible effect of these pathologies on the degree of phase synchronization between cortical areas. The degree of phase synchrony was measured by two recently developed measures which are more suitable than classical indices like correlation or coherence when dealing with nonlinear and non-stationary signals like the EEG. Signals were reduced to seven frequency bands (delta, theta, alpha-1, alpha-2, beta-1, beta-2 and gamma) which were statistically compared between the normal and the other two groups. It was found that the degree of long-range synchrony was significantly reduced for both pathological groups as compared with the control group. No clear differences were found in the degrees of short-range synchrony.