Publications by authors named "Coufal D"

Suitability of shallow (one-hidden-layer) networks with translation-invariant kernel units for function approximation and classification tasks is investigated. It is shown that a critical property influencing the capabilities of kernel networks is how the Fourier transforms of kernels converge to zero. The Fourier transforms of kernels suitable for multivariable approximation can have negative values but must be almost everywhere nonzero.

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In this comparative study, six causality detection methods were compared, namely, the Granger vector autoregressive test, the extended Granger test, the kernel version of the Granger test, the conditional mutual information (transfer entropy), the evaluation of cross mappings between state spaces, and an assessment of predictability improvement due to the use of mixed predictions. Seven test data sets were analyzed: linear coupling of autoregressive models, a unidirectional connection of two Hénon systems, a unidirectional connection of chaotic systems of Rössler and Lorenz type and of two different Rössler systems, an example of bidirectionally connected two-species systems, a fishery model as an example of two correlated observables without a causal relationship, and an example of mediated causality. We tested not only 20000 points long clean time series but also noisy and short variants of the data.

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Nonparametric detection of coupling delay in unidirectionally and bidirectionally coupled nonlinear dynamical systems is examined. Both continuous and discrete-time systems are considered. Two methods of detection are assessed-the method based on conditional mutual information-the CMI method (also known as the transfer entropy method) and the method of convergent cross mapping-the CCM method.

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Background: Breast carcinomas represent a heterogeneous group of tumors diverse in behavior, outcome, and response to therapy. Identification of proteins resembling the tumor biology can improve the diagnosis, prediction, treatment selection, and targeting of therapy. Since the beginning of the post-genomic era, the focus of molecular biology gradually moved from genomes to proteins and proteomes and to their functionality.

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The soluble methane monooxygenase (sMMO) hydroxylase is a prototypical member of the class of proteins with non-heme carboxylate-bridged diiron sites. The sMMO subclass of enzyme systems has several distinguishing characteristics, including the ability to catalyze hydroxylation or epoxidation chemistry, a multisubunit hydroxylase containing diiron centers in its alpha subunits, and the requirement of a coupling protein for optimal activity. Sequence homology alignment of known members of the sMMO family was performed in an effort to identify protein regions giving rise to these unique features.

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The soluble methane monooxygenase system from Methylococcus capsulatus (Bath) catalyzes the oxidation of methane to methanol and water utilizing dioxygen at a non-heme, carboxylate-bridged diiron center housed in the hydroxylase (H) component. To probe the nature of the reductive activation of dioxygen in this system, reactions of an analogous molecule, nitric oxide, with the diiron(II) form of the enzyme (Hred) were investigated by both continuous and discontinuous kinetics methodologies using optical, EPR, and Mössbauer spectroscopy. Reaction of NO with Hred affords a dinitrosyl species, designated Hdinitrosyl, with optical spectra (lambdamax = 450 and 620 nm) and Mössbauer parameters (delta = 0.

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The authors analyze the results of treatment of AC luxation by the method of coracoclavicular cerclage at the First Surgical Clinical of the Faculty Hospital and Policlinic in Olomouc in 1968-1988. A total of 18 patients were examined after an average period of 12.5 years following operation.

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