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1.
J Sports Sci ; 41(10): 972-989, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37742342

RESUMO

Badminton footwork has been characterised with jump-landing, cross step, side side and lunges, which requires movement agility to facilitate on-court performance. A novel badminton shoe design with systematic increase of lateral wedge hardness (Asker C value of 55, 60, 65, and 70) was developed and investigated in this study, aiming to analyse the dose-response effect of incremental wedge hardness on typical badminton footwork. Stance time and joint stiffness were employed to investigate the footwork performance, and the factorial Statistical non-Parametric Mapping and Principal Component Analysis (PCA) were used to quantify the biomechanical responses over the stance. As reported, shorter contact times (decreased by 8.9%-13.5%) and increased joint stiffness (in side step) of foot-ankle complex were found, suggesting improved footwork stability and agility from increased hardness. Time-varying differences were noted during the initial landing and driving-off phase of cross and side steps and drive-off returning of lunges, suggesting facilitated footwork performance. The reconstructed modes of variations from PCA further deciphered the biomechanical response to the wedge dosage, especially during drive-off, to understand the improved footwork agility and stability.


Assuntos
Extremidade Inferior , Esportes com Raquete , Humanos , Fenômenos Biomecânicos/fisiologia , Dureza , Extremidade Inferior/fisiologia , Articulações/fisiologia , Esportes com Raquete/fisiologia
2.
Int J Neurosci ; 130(9): 917-925, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31903823

RESUMO

Purpose:In this article, we propose current source density (CSD) as a marker for diagnosis of Attention Deficit and Hyperactivity Disorder (ADHD) children for the first time.Materials and methods: A source localization method (sLORETA) was used to find the source of abnormality in the CSD in electrical distribution of different frequency bands in resting state EEG for the ADHD children in comparison to the normal children using statistical nonparametric mapping (SnPM) test. Resting-state EEG in eye-open (EO) condition was recorded from 13 ADHD and 15 age-matched normal children (aged between 6 and 13).Results: Significant differences were found in the CSD of three frequency bands: delta, theta, and alpha in the parietal lobe, between ADHD and normal groups.Conclusions: Higher CSD in the parietal lobe for ADHD children was found which suggests that an abnormality exists in the parietal lobe of children with ADHD which can be related to the attention shifting problem in these children.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Ondas Encefálicas/fisiologia , Eletroencefalografia , Neuroimagem Funcional , Lobo Parietal/fisiopatologia , Adolescente , Criança , Eletroencefalografia/métodos , Feminino , Neuroimagem Funcional/métodos , Humanos , Masculino
3.
Bioengineering (Basel) ; 9(11)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36421104

RESUMO

This study compares foot-ankle temporal kinematics characteristics during planned and unplanned gait termination (PGT and UGT) in subjects with different arch stiffnesses (ASs) based on the statistical nonparametric mapping (SnPM) method. By measuring three-dimensional arch morphological parameters under different loading conditions, 28 healthy male subjects were classified and participated in gait termination (GT) tests to collect metatarsophalangeal (MTP) and ankle-joint kinematics data. The two-way repeated-measures ANOVA using SnPM was employed to assess the impacts of AS on foot-ankle kinematics during PGT and UGT. Our results show that joint angles (MTP and ankle joints) were altered owing to AS and GT factors. The flexible arches hahadve periods of significantly greater MTP and ankle joint angles than those of stiff arches during the stance phase of GT, whereas subjects exhibited significantly smaller ankle and MTP joint angles during UGT. These results add additional insights into the morphological arch biomechanical function, and the comprehensive compensatory adjustment of lower-limb joints during gait stopping caused by unplanned stimulation.

4.
Sports Biomech ; : 1-21, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36541614

RESUMO

The purpose of this study was to determine how the intrinsic head-trunk coordination dynamics that exist during forward running are modified during a dynamic sidestepping task. Fourteen athletes performed both forward running and sidestepping tasks. Head-trunk coordination and range of motion were assessed during the flight and stance phases in the transverse and sagittal planes. The sidestepping task resulted in greater in-phase head-trunk coordination during stance in the transverse plane (p < .001, ES = -1.71) and in reduced anti-phase coordination between head and trunk in the sagittal plane (p < .001, ES = 1.52). Statistical non-parametric mapping revealed that during sidestepping the sagittal plane coupling angle shifted away from anti-phase earlier during midstance. The sidestepping task resulted in greater transverse and sagittal plane head and trunk range of motion and greater vertical trunk centre of mass displacement. Sidestepping modified the intrinsic coordination dynamics that are present during forward running, with greater transverse plane head contributions and reductions in compensatory sagittal plane head motion, which may occur during the transition from weight acceptance to propulsion during the stance phase. These changes in the intrinsic coordination dynamics of the upper body during sidestepping tasks may impact visual perception and readiness compared to forward running during complex sports tasks.

5.
Med Phys ; 45(3): 1108-1117, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29369364

RESUMO

PURPOSE: The identification of a brain tumor imaged with PET or SPECT is usually performed with visual inspection of an expert medical clinician. However an automated diagnostic of such images hasn't been established or applied. In this study, we explored the possibility of establishing an automated statistical analysis for the diagnosis of glioma by means of IPA-SPECT data. METHODS: On the basis of a dataset of 100 patients that have undergone MRI and IPA-SPECT acquisition, in this work, we identify an automated workflow. Three different approaches were explored: I. statistical non-parametric mapping analysis (SnPM), II. statistical non-parametric analysis with an increased number of permutations due to sign-flipping function (PALM) and III. statistical parametric analysis (SPM). The automated methods were compared with the visual inspection. RESULTS: The study proved PALM and SPM approaches to have a high diagnostic power. Compared to the parametric methods, the non-parametric method is the mathematically correct approach for the problem in question. If we take the high resolution structural MRI information into account, the diagnostic power of PALM was not significantly inferior to the visual inspection (P = 0.5150), showing an area under the ROC curve (AUC) smaller only by less than 3%. CONCLUSIONS: The automated diagnostic method based on statistical inference, here applied to diagnose glioma tumors in IPA-SPECT data, seems to be a promising tool that can support the visual investigation in nuclear medicine. Moreover in the foreseeable future, the presented methodology has a big potential in various application like localization of active tumor tissues in surgical resection or stereotactic radiosurgery.


Assuntos
Glioma/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Estatística como Assunto , Tomografia Computadorizada de Emissão de Fóton Único , Automação , Humanos
6.
Neuroimage Clin ; 20: 336-346, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30112275

RESUMO

Synchronization of neural activity as measured with functional connectivity (FC) is increasingly used to study the neural basis of brain disease and to develop new treatment targets. However, solid evidence for a causal role of FC in disease and therapy is lacking. Here, we manipulated FC of the ipsilesional primary motor cortex in ten chronic human stroke patients through brain-computer interface technology with visual neurofeedback. We conducted a double-blind controlled crossover study to test whether manipulation of FC through neurofeedback had a behavioral effect on motor performance. Patients succeeded in increasing FC in the motor cortex. This led to improvement in motor function that was significantly greater than during neurofeedback training of a control brain area and proportional to the degree of FC enhancement. This result provides evidence that FC has a causal role in neurological function and that it can be effectively targeted with therapy.


Assuntos
Atividade Motora , Córtex Motor/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Neurorretroalimentação/métodos , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Adulto , Idoso , Estudos Cross-Over , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Córtex Motor/fisiologia , Rede Nervosa/fisiologia , Neurorretroalimentação/fisiologia , Estimulação Luminosa/métodos , Acidente Vascular Cerebral/fisiopatologia
7.
Int J Psychophysiol ; 90(2): 282-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24056021

RESUMO

Individuals with depression are excessively sensitive to negative feedback and therefore overly cautious. To explore the neural mechanisms of response monitoring which contributed to their impaired behavioral adjustment, we recruited 22 individuals with depressive disorder and 24 healthy controls. Component analysis of the error-related negativity (ERN) and correct-related negativity (CRN), and sLORETA analysis of the ERN and CRN were combined. The comparable error rate and longer reaction time (RT) in individuals with depression as compared to healthy controls suggested a trade-off between accuracy and speed. The amplitude of the ERN and CRN was significantly enhanced in depression. Further sLORETA localizations of the ERN and CRN showed a significantly stronger current density with an extensive distribution in the anterior cingulate cortex (ACC), medial frontal cortex (MFC), inferior parietal lobule (IPL) and superior temporal gyrus (STG) in individuals with depression than in healthy controls. Increased activities in the ACC and MFC indexed increased response monitoring during automatic error detection, while hyperactivity over IPL and STG might indicate high uncertainness after error responses in depression. The hyperactivity within an extensive cortical distribution might be the neural basis of the excessive sensitivity to errors and the conservative accuracy/speed strategy in depression.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Depressão/diagnóstico por imagem , Depressão/fisiopatologia , Potenciais Evocados/fisiologia , Adulto , Variação Contingente Negativa/fisiologia , Eletroencefalografia , Fenômenos Eletromagnéticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Tempo de Reação/fisiologia , Tomografia Computadorizada por Raios X
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