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1.
Heliyon ; 6(6): e04158, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32551391

RESUMEN

Classification of behavior into principal categories of approach and avoidance is grounded in evolutionary considerations and multiple results of behavioral, self-report, and brain-activity analyses. Contrasted via measures of cognitive processes, avoidance is accompanied by greater cognitive engagement than approach. Considering outcome as a key constituent of behavioral underpinnings, we interpret approach/avoidance distinction in terms of structure of experience: avoidance domain provides more detailed interaction with the environment, than approach domain. Learning outwardly similar behaviors aimed at gain or loss outcomes manifests formation of different structures that underlie further learning. Therefore, we predicted difference of learning transfer between gain and loss contexts that was revealed here by introducing two tasks for different groups of schoolchildren in Finland and Russia. The cultural specificity of gain/loss differences was also evident with employed measures, including error rate and post-error slowing. The results support that avoidance-motivated behavior is organized as a more complex organism-environment interaction, than the approach-motivated behavior.

2.
Vestn Khir Im I I Grek ; 174(1): 23-5, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-25962289

RESUMEN

The ultrasonic signs or focal formations have a defining value for indication of fine-needle aspiration biopsy of thyroid nodules. The size and dynamics of growth aren't so important. The evaluation of indications for performing a thyroid nodules biopsy was made in 6403 patients. It was proved that the size of thyroid nodules hadn't any value for the indications and technique of aspiration biopsy. It was stated that a subjectivity assessment, many errors and parameters variety took place in clinical and ultrasound examination in the case of thyroid nodules changes. Indications for biopsy based on the size of nodules hadn't any theoretical or practical value. The indications according to TIRADS system are reasonable. Their application considerably improved obtaining an informative material and increased the probability of thyroid tumor detection.


Asunto(s)
Biopsia con Aguja Fina/métodos , Glándula Tiroides/patología , Nódulo Tiroideo , Tiroidectomía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Reproducibilidad de los Resultados , Estudios Retrospectivos , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/patología , Nódulo Tiroideo/cirugía , Ultrasonografía
3.
Phys Rev Lett ; 108(19): 192001, 2012 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-23003028

RESUMEN

The COMPASS Collaboration at CERN has investigated the π- γ → π- π- π+ reaction at center-of-momentum energy below five pion masses, sqrt[s]<5m(π), embedded in the Primakoff reaction of 190 GeV pions impinging on a lead target. Exchange of quasireal photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, t'<0.001 GeV2/c2. Using partial-wave analysis techniques, the scattering intensity of Coulomb production described in terms of chiral dynamics and its dependence on the 3π-invariant mass m(3π)=sqrt[s] were extracted. The absolute cross section was determined in seven bins of sqrt[s] with an overall precision of 20%. At leading order, the result is found to be in good agreement with the prediction of chiral perturbation theory over the whole energy range investigated.

4.
J Breath Res ; 5(1): 016005, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21358039

RESUMEN

This work describes the gas-sensitive properties of a one-dimensional organic conductor before and after exposure to carbon monoxide and human breath. A sensitive material, an anion-radical salt of tetracyanoquinodimethane, has been investigated by infrared spectroscopy and electrical resistivity measurements. Drastic spectral and electrical changes are found after gas exposure showing that the compound interacts strongly with human breath, carbon monoxide, and ammonia. Under breath action the resistance changes by more than three orders of magnitude while the adsorption of CO, one of the components of breath, results in a decrease in both IR absorption and electrical conductivity. The intensity of the IR absorption spectrum of the material in the CO medium decreases down to 30% in the 2180-2500 cm(-1) range. This absorption varies by about 10% between 750 and 2500 cm(-1) after breath action. Direct electrical measurements show that actions of donor or acceptor gas result in opposite changes of electric resistance. The electrical resistance of the sample can drop down to 0.4 MΩ due to the pulse action of ammonia at 4 ppm concentration, while it increases upon exposure to carbon monoxide media at concentrations of 6-25 ppm. The response signal of the investigated samples changes proportionally to the concentration of the acting gas. The results substantiate prominent gas sensitivity of the investigated material, which might find applications for breath analysis, in particular, for the development of noninvasive diagnosis of gastric diseases.


Asunto(s)
Amoníaco/análisis , Pruebas Respiratorias/instrumentación , Pruebas Respiratorias/métodos , Monóxido de Carbono/análisis , Espectrofotometría Infrarroja/métodos , Impedancia Eléctrica , Humanos , Nitrilos
5.
Phys Rev Lett ; 104(24): 241803, 2010 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-20867295

RESUMEN

The COMPASS experiment at the CERN SPS has studied the diffractive dissociation of negative pions into the π- π- π+ final state using a 190 GeV/c pion beam hitting a lead target. A partial wave analysis has been performed on a sample of 420,000 events taken at values of the squared 4-momentum transfer t' between 0.1 and 1 GeV2/c2. The well-known resonances a1(1260), a2(1320), and π2(1670) are clearly observed. In addition, the data show a significant natural-parity exchange production of a resonance with spin-exotic quantum numbers J(PC)=1-+ at 1.66 GeV/c2 decaying to ρπ. The resonant nature of this wave is evident from the mass-dependent phase differences to the J(PC)=2-+ and 1++ waves. From a mass-dependent fit a resonance mass of (1660±10(-64)(+0)) MeV/c2 and a width of (269±21(-64)(+42)) MeV/c2 are deduced, with an intensity of (1.7±0.2)% of the total intensity.

6.
Neuroscience ; 136(1): 33-42, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16182454

RESUMEN

Learning has been shown to induce changes in neuronal gene expression and to produce development of task-specific neuronal activity. The connection between these two features of neuronal plasticity remains of a great interest. To address this issue we compared distribution of c-Fos expressing and task-related neurons in the rat cerebral cortex following instrumental learning of appetitive lever-press task. The number of Fos-positive neurons was determined immunohistochemically in the retrosplenial and the motor cortex of naive ("control" group), newly trained ("acquisition" group) and overtrained ("performance" group) animals. A significant activation of c-Fos expression was observed in the neurons of the retrosplenial but not motor cortex in the "acquisition" group rats, as compared with the "control" and "performance" groups. In accordance with this c-Fos expression difference, the retrosplenial cortex of the trained animals contained significantly more neurons with lever-press-related activity than the motor cortex. Therefore, the two examined cortical areas showed a parallel between experience-dependent induction of c-Fos and development of task-related neuronal activity. These data support a notion that learning-induced activation of c-Fos is associated with long-term neurophysiological changes produced by training.


Asunto(s)
Corteza Cerebral/fisiología , Condicionamiento Operante/fisiología , Neuronas/fisiología , Proteínas Proto-Oncogénicas c-fos/metabolismo , Animales , Conducta Animal/fisiología , Mapeo Encefálico , Corteza Cerebral/citología , Electrofisiología , Conducta Alimentaria/fisiología , Inmunohistoquímica , Masculino , Corteza Motora/citología , Corteza Motora/metabolismo , Ratas , Ratas Long-Evans
7.
Phys Rev Lett ; 94(20): 202002, 2005 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-16090237

RESUMEN

First measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarized 6LiD target are presented. The data were taken in 2002 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. The Collins asymmetry turns out to be compatible with zero, as does the measured Sivers asymmetry within the present statistical errors.

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