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1.
Oxid Med Cell Longev ; 2014: 402631, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24864189

RESUMO

The influence of exercise combined with whole-body cryotherapy (WBC) on the oxidant/antioxidant balance in healthy men was assessed. The study included 16 kayakers of the Polish National Team, aged 22.7 ± 2.6, subjected to WBC (-120°C--145°C; 3 min) twice a day for the first 10 days of a 19-day physical training cycle: pre exercise morning stimulation and post exercise afternoon recovery. Blood samples were taken on Day 0 (baseline) and on Days 5, 11 and 19. The serum concentration of malondialdehyde (MDA), conjugated dienes (CD), thiobarbituric acid reactive substances (TBARS), protein carbonyls, vitamin E, urea, cortisol, and testosterone were determined, along with the glutathione peroxidase (GPx) activity, the total antioxidant capacity (TAC), and morphological blood parameters. On 5th day of exercise/WBC, the baseline GPx activity decreased by 15.1% (P < 0.05), while on 19th day, it increased by 19.7% (P < 0.05) versus Day 5. On Day 19 TBARS concentration decreased versus baseline and Day 5 (by 15.9% and 17.4%, resp.; P < 0.01). On 19 Day urea concentration also decreased versus 11 Day; however, on 5th and 11th days the level was higher versus baseline. Combining exercise during longer training cycles with WBC may be advantageous.


Assuntos
Antioxidantes/metabolismo , Crioterapia , Exercício Físico , Peroxidação de Lipídeos , Oxidantes/metabolismo , Adulto , Contagem de Células Sanguíneas , Análise Química do Sangue , Glutationa Peroxidase/metabolismo , Humanos , Leucócitos/citologia , Leucócitos/enzimologia , Leucócitos/metabolismo , Masculino , Estresse Oxidativo , Oxirredutases/sangue , Oxirredutases/metabolismo , Fatores de Tempo , Adulto Jovem
2.
J Acoust Soc Am ; 132(5): 3484-93, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23145628

RESUMO

Comparable large-scale surveys including an on-site pitch-naming test were conducted with music students in Japan and Poland to obtain more convincing estimates of the prevalence of absolute pitch (AP) and examine how musical experience relates to AP. Participants with accurate AP (95% correct identification) accounted for 30% of the Japanese music students, but only 7% of the Polish music students. This difference in the performance of pitch naming was related to the difference in musical experience. Participants with AP had begun music training at an earlier age (6 years or earlier), and the average year of commencement of musical training was more than 2 years earlier for the Japanese music students than for the Polish students. The percentage of participants who had received early piano lessons was 94% for the Japanese musically trained students but was 72% for the Polish music students. Approximately one-third of the Japanese musically trained students had attended the Yamaha Music School, where lessons on piano or electric organ were given to preschool children in parallel with fixed-do solfège singing training. Such early music instruction was not as common in Poland. The relationship of AP with early music training is discussed.


Assuntos
Música , Discriminação da Altura Tonal , Estudantes/psicologia , Estimulação Acústica , Adolescente , Adulto , Fatores Etários , Análise de Variância , Audiometria , Criança , Pré-Escolar , Discriminação Psicológica , Humanos , Japão , Pessoa de Meia-Idade , Polônia , Reconhecimento Psicológico , Adulto Jovem
3.
J Acoust Soc Am ; 131(1): 987-92, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22280721

RESUMO

A psychophysical pitch function, describing the relation of perceived magnitude of pitch to the frequency of a pure tone, was determined by absolute magnitude estimation. Pitch estimates were made by listeners with relative pitch and by absolute pitch possessors for 27 tones spanning a frequency range of 31.5-12,500 Hz in 1/3 octave steps. Results show that the pitch function, plotted in log-log coordinates, is steeper below 200 Hz than at higher frequencies. It is hypothesized that the pitch function's bend may reflect the diversity of neurophysiological mechanisms of pitch encoding in frequency ranges below and above 200 Hz. The variation of the function's slope implies that pitch distances between tones with the same frequency ratios are perceived as larger below 200 Hz than at higher frequencies. It is argued that this implication may apply only to a purely sensory concept of pitch distance and cannot be extended to the perception of musical intervals, a phenomenon governed by musical cognitive principles. The results also show that pitch functions obtained for listeners with relative and absolute pitch have a similar shape, which means that quantitative pitch relations determined for both groups of listeners do not differ appreciably along the frequency scale.


Assuntos
Música , Discriminação da Altura Tonal/fisiologia , Cognição/fisiologia , Humanos , Julgamento , Psicoacústica
4.
J Environ Radioact ; 99(10): 1558-65, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18272268

RESUMO

Radiocarbon concentration in the atmosphere is significantly lower in areas where man-made emissions of carbon dioxide occur. This phenomenon is known as Suess effect, and is caused by the contamination of clean air with non-radioactive carbon from fossil fuel combustion. The effect is more strongly observed in industrial and densely populated urban areas. Measurements of carbon isotope concentrations in a study area can be compared to those from areas of clear air in order to estimate the amount of carbon dioxide emission from fossil fuel combustion by using a simple mathematical model. This can be calculated using the simple mathematical model. The result of the mathematical model followed in this study suggests that the use of annual rings of trees to obtain the secular variations of 14C concentration of atmospheric CO2 can be useful and efficient for environmental monitoring and modeling of the carbon distribution in local scale.


Assuntos
Contaminação Radioativa do Ar/análise , Dióxido de Carbono/análise , Árvores/crescimento & desenvolvimento , Radioisótopos de Carbono/análise , Cidades , Combustíveis Fósseis/análise , Modelos Teóricos , Monitoramento de Radiação/métodos
5.
Eur J Appl Physiol ; 100(2): 137-42, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17458576

RESUMO

Effects of whole-body cryostimulation on lysosomal enzyme activity: acid phosphatase (AcP), arylsulphatase (ASA) and cathepsin D (CTS D), as well as on the creatine kinase (CK), and the cortisol concentration in the serum of kayakers during training were studied. Additionally, the effect of a single cryostimulation treatment in untrained men was evaluated. The kayakers were subjected to a ten-day training cycle, in which training sessions were preceded by whole-body cryostimulation at a temperature ranging from -120 to -140 degrees C, and to a control training without cryostimulation. Blood samples were taken from the kayakers before the training and after the sixth and tenth day of training and from untrained men before and after cryostimulation. The single cryostimulation caused a 30% (P < 0.05) decrease in the CK activity in untrained men. After the sixth day of training with cryostimulation, the activity of ASA was 46% (P < 0.001), AcP 32% (P < 0.05) and CK 34% lower (P < 0.05) than after the sixth day of training without cryostimulation. The results support that preceding training with whole-body cryostimulation alleviates exertion stress by a stabilisation of lysosomal membranes.


Assuntos
Temperatura Baixa , Lisossomos/enzimologia , Esforço Físico/fisiologia , Fosfatase Ácida/metabolismo , Adulto , Arilsulfatases/metabolismo , Câmaras de Exposição Atmosférica , Catepsina D/metabolismo , Creatina Quinase/metabolismo , Humanos , Hidrocortisona/metabolismo , Masculino , Músculo Esquelético/metabolismo
6.
Percept Psychophys ; 64(8): 1337-45, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12519030

RESUMO

Musically trained listeners compared a notated melody presented visually and a comparison melody presented auditorily, and judged whether they were exactly the same or not, with respect to relative pitch. Listeners who had absolute pitch showed the poorest performance for melodies transposed to different pitch levels from the notated melodies, whereas they exhibited the highest performance for untransposed melodies. By comparison, the performance of melody recognition by listeners who did not have absolute pitch was not influenced by the actual pitch level at which melodies were played. These results suggest that absolute-pitch listeners tend to rely on absolute pitch even in recognizing transposed melodies, for which the absolute-pitch strategy is not useful.


Assuntos
Música , Percepção da Altura Sonora , Reconhecimento Psicológico , Percepção Auditiva , Humanos
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