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1.
Cell Biochem Biophys ; 60(3): 329-34, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21301991

RESUMO

This study investigates the effects produced by an increased concentration of glucose in a suspending medium on the erythrocytes Information Theory quantifiers. Erythrocytes, which were obtained from eight healthy volunteers, were washed and incubated in vitro with glucose solutions at different concentrations. The measured Wavelet-based Information Theory quantifiers include the Relative Wavelet Energy (RWE), the Normalized Total Wavelet Shannon Entropy (NTWS), MPR-Statistical Complexity Measure (SCM) and entropy-complexity plane. The results show that the increase in glucose concentration does not produce significant changes on the RWE, while significant ones on the NTSE, which combined with SCM values allow to identify different behaviour for all the different populations in the entropy-complexity plane. Modification in the hemorheological properties of cells could be clearly detected with these Wavelet-based Information Theory quantifiers.


Assuntos
Eritrócitos/efeitos dos fármacos , Glucose/farmacologia , Entropia , Humanos , Modelos Teóricos
2.
Biocell ; Biocell;31(1): 41-49, abr. 2007. tab, graf
Artigo em Inglês | LILACS | ID: lil-491536

RESUMO

An in vitro collection has been Established with selected European aspen from Palencia province (Spain). Currently, this collection includes 32 high quality clones, selected for their good bearing and healthy state. Most of them belong to different discrete local populations. Populus tremula L. was propagated in proliferation Aspen Culture Medium; they required subculture every 3 months. The purpose of this study was, therefore, to select a medium which allows the maintenance of 32 clones for a period longer than 3 months without subculture and to observe the behavior of those clones in 15 different culture medium compositions. Seven nodal cutting stem explants from each clone were cultured in parallel in the different media. One and three months after setting on the stem explants, the number and the size of shoots, the root size, the presence or absence of callus and the survival, were evaluated. The survival was monthly recorded during 8 months. Taking into account the explant development, four media were proposed for collection preservation. One of them, Ga, with a reduction of salts, sucrose, 6-benzoaminopurine, omitting adenine sulphate and 1-naphthalene acetic acid, is the most economical. Behavior observations of the 32 clones in the 15 medium compositions showed the influence of the genotype of the clones.


Assuntos
Árvores/crescimento & desenvolvimento , Células Clonais , Estruturas Vegetais/crescimento & desenvolvimento , Meios de Cultura/química , Populus/crescimento & desenvolvimento , Técnicas de Cultura , Preservação Biológica , Espanha
3.
Biocell ; Biocell;31(1): 41-49, abr. 2007. tab, graf
Artigo em Inglês | BINACIS | ID: bin-122871

RESUMO

An in vitro collection has been Established with selected European aspen from Palencia province (Spain). Currently, this collection includes 32 high quality clones, selected for their good bearing and healthy state. Most of them belong to different discrete local populations. Populus tremula L. was propagated in proliferation Aspen Culture Medium; they required subculture every 3 months. The purpose of this study was, therefore, to select a medium which allows the maintenance of 32 clones for a period longer than 3 months without subculture and to observe the behavior of those clones in 15 different culture medium compositions. Seven nodal cutting stem explants from each clone were cultured in parallel in the different media. One and three months after setting on the stem explants, the number and the size of shoots, the root size, the presence or absence of callus and the survival, were evaluated. The survival was monthly recorded during 8 months. Taking into account the explant development, four media were proposed for collection preservation. One of them, Ga, with a reduction of salts, sucrose, 6-benzoaminopurine, omitting adenine sulphate and 1-naphthalene acetic acid, is the most economical. Behavior observations of the 32 clones in the 15 medium compositions showed the influence of the genotype of the clones.(AU)


Assuntos
Estruturas Vegetais/crescimento & desenvolvimento , Populus/crescimento & desenvolvimento , Meios de Cultura/química , Células Clonais , Árvores/crescimento & desenvolvimento , Técnicas de Cultura , Preservação Biológica , Espanha
4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(2 Pt 1): 021115, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17358321

RESUMO

Efficient tools to characterize stochastic processes are discussed. Quantifiers originally proposed within the framework of information theory, like entropy and statistical complexity, are translated into wavelet language, which renders the above quantifiers into tools that exhibit the important "localization" advantages provided by wavelet theory. Two important and popular stochastic processes, fractional Brownian motion and fractional Gaussian noise, are studied using these wavelet-based informational tools. Exact analytical expressions are obtained for the wavelet probability distribution. Finally, numerical simulations are used to validate our analytical results.

5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(6 Pt 1): 061114, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18233821

RESUMO

By recourse to appropriate information theory quantifiers (normalized Shannon entropy and Martín-Plastino-Rosso intensive statistical complexity measure), we revisit the characterization of Gaussian self-similar stochastic processes from a Bandt-Pompe viewpoint. We show that the ensuing approach exhibits considerable advantages with respect to other treatments. In particular, clear quantifiers gaps are found in the transition between the continuous processes and their associated noises.

6.
J Neurosci Methods ; 153(2): 163-82, 2006 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-16675027

RESUMO

Wavelet-based informational tools for quantitative electroencephalogram (EEG) record analysis are reviewed. Relative wavelet energies, wavelet entropies and wavelet statistical complexities are used in the characterization of scalp EEG records corresponding to secondary generalized tonic-clonic epileptic seizures. In particular, we show that the epileptic recruitment rhythm observed during seizure development is well described in terms of the relative wavelet energies. In addition, during the concomitant time-period the entropy diminishes while complexity grows. This is construed as evidence supporting the conjecture that an epileptic focus, for this kind of seizures, triggers a self-organized brain state characterized by both order and maximal complexity.


Assuntos
Encéfalo/fisiologia , Eletroencefalografia , Processamento de Sinais Assistido por Computador , Adolescente , Adulto , Encéfalo/fisiopatologia , Criança , Entropia , Epilepsia/fisiopatologia , Feminino , Humanos , Masculino , Fatores de Tempo
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