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Composite materials have gained significant attention owing to the synergistic effects of their constituent materials, thereby facilitating their utilization in new applications or in improving the existing ones. In this study, a composite based on nickel phthalocyanine (NiTsPc), zinc oxide nanoparticles (ZnONPs), and carbon nanotubes (CNT) was developed and subsequently immobilized on a pyrolytic graphite electrode (PGE). The PGE/NiTsPc-ZnONPs-CNT was identified as a selective catalytic hybrid system for detection of neurotransmitter dopamine (DA). The electrochemical and morphological characterizations were conducted using atomic force microscopy (AFM). Chronoamperometry and differential pulse voltammetry (DPV) were used to detect DA and detection limits of 24 nM and 7.0 nM was found, respectively. In addition, the effects of some possible DA interferents, such as ascorbic acid, uric acid, and serotonin, on DA response were evaluated. Their presence did not show significant variations in the DA electrochemical response. The high specificity and sensitivity of PGE/NiTsPc-ZnONPs-CNT for DA enabled its direct detection in human serum without sample pretreatment as well as in DA-enriched serum samples, whose recovery levels were close to 100%, thereby confirming the effectiveness of the proposed method. In general, PGE/NiTsPc-ZnONPs-CNT is a promising candidate for future applications in clinical diagnosis.

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A percepção do tempo é subjetiva e relativa, além de modulada por aspectos neurofuncionais como a emoção, memória e atenção, e está alterada em algumas patologias neuropsiquiátricas. Entretanto, ainda existe muita discussão sobre quais modelos de percepção do tempo são mais aceitáveis e como estão envolvidos nas doenças neurológicas. Desse modo, o conhecimento do fisioterapeuta sobre a percepção do tempo e seus modelos é um fator que pode direcionar ao tratamento do paciente, pois há uma ativação de áreas corticais na percepção do tempo que também são envolvidas na motricidade. Um modelo geral de processamento de informação temporal deve comportar um oscilador, acumulador e comparador dos dados obtidos com a memória. No entanto, as bases neurofisiológicas dos mecanismos de percepção do tempo ainda não são totalmente determinadas, existindo modelos que apontam a existência de um mecanismo neural único ou a de vários dispositivos especializados em diferentes escalas. Embora as mudanças na percepção do tempo não caracterizem uma doença, diversos comprometimentos neurológicos podem acometer a percepção temporal. Apesar dos esforços não se pode concluir sobre quais áreas desempenham a função temporizadora, apenas inferir por meio de experimentos realizados em animais e humanos. (AU)

The time perception is subjective, relative and modulated by neurofunctional aspects such as emotion, memory and attention. This is altered in some neuropsychiatric disorders. However, there is still much debate about which time perception models are more acceptable and how they are involved in neurological diseases. Thus, the physical therapist knowledge of time perception and its models is a factor that can direct the patient treatment, as there is activation in cortical areas which are also involved in motor function. A general model temporal information processing must contain an oscillator, accumulator and comparator data obtained from the memory. However, the neurophysiology of time perception mechanisms are still not fully determined, models exist which indicate the existence of a single neural mechanism or various specialized devices with different scales. Although the change in the time perception does not characterize a disease, various neurological impairments can affect time perception. Despite efforts cannot conclude on areas which perform the timer function, only inferred through performed in animal and human experiments. (AU)

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[Purpose] Stretching using proprioceptive neuromuscular facilitation involve physiological reflex mechanisms through submaximal contraction of agonists which activate Golgi organ, promoting the relaxation reflex. The aim of this study was to evaluate the effects of proprioceptive neuromuscular facilitation alone and with prior application of cryotherapy and thermotherapy on hamstring stretching. [Subjects and Methods] The sample comprised of 32 young subjects with hamstring retraction of the right limb. The subjects were randomly allocated to four groups: the control, flexibility PNF, flexibility PNF associated with cryotherapy, flexibility PNF in association with ultrasound therapy. [Results] After 12 stretching sessions, experimental groups showed significant improvements compared to the control group. Moreover, we did not find any significant differences among the experimental groups indicating PNF stretching alone elicits similar results to PNF stretching with prior administration of cryotherapy or thermotherapy. [Conclusion] PNF without other therapy may be a more practical and less expensive choice for clinical care.