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1.
Sensors (Basel) ; 23(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36991992

RESUMO

BACKGROUND: This article presents the system architecture and validation of the NeuroSuitUp body-machine interface (BMI). The platform consists of wearable robotics jacket and gloves in combination with a serious game application for self-paced neurorehabilitation in spinal cord injury and chronic stroke. METHODS: The wearable robotics implement a sensor layer, to approximate kinematic chain segment orientation, and an actuation layer. Sensors consist of commercial magnetic, angular rate and gravity (MARG), surface electromyography (sEMG), and flex sensors, while actuation is achieved through electrical muscle stimulation (EMS) and pneumatic actuators. On-board electronics connect to a Robot Operating System environment-based parser/controller and to a Unity-based live avatar representation game. BMI subsystems validation was performed using exercises through a Stereoscopic camera Computer Vision approach for the jacket and through multiple grip activities for the glove. Ten healthy subjects participated in system validation trials, performing three arm and three hand exercises (each 10 motor task trials) and completing user experience questionnaires. RESULTS: Acceptable correlation was observed in 23/30 arm exercises performed with the jacket. No significant differences in glove sensor data during actuation state were observed. No difficulty to use, discomfort, or negative robotics perception were reported. CONCLUSIONS: Subsequent design improvements will implement additional absolute orientation sensors, MARG/EMG based biofeedback to the game, improved immersion through Augmented Reality and improvements towards system robustness.


Assuntos
Exoesqueleto Energizado , Reabilitação Neurológica , Robótica , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Dispositivos Eletrônicos Vestíveis , Humanos
2.
JMIR Res Protoc ; 11(9): e41152, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36099009

RESUMO

BACKGROUND: Spinal cord injury (SCI) constitutes a major sociomedical problem, impacting approximately 0.32-0.64 million people each year worldwide; particularly, it impacts young individuals, causing long-term, often irreversible disability. While effective rehabilitation of patients with SCI remains a significant challenge, novel neural engineering technologies have emerged to target and promote dormant neuroplasticity in the central nervous system. OBJECTIVE: This study aims to develop, pilot test, and optimize a platform based on multiple immersive man-machine interfaces offering rich feedback, including (1) visual motor imagery training under high-density electroencephalographic recording, (2) mountable robotic arms controlled with a wireless brain-computer interface (BCI), (3) a body-machine interface (BMI) consisting of wearable robotics jacket and gloves in combination with a serious game (SG) application, and (4) an augmented reality module. The platform will be used to validate a self-paced neurorehabilitation intervention and to study cortical activity in chronic complete and incomplete SCI at the cervical spine. METHODS: A 3-phase pilot study (clinical trial) was designed to evaluate the NeuroSuitUp platform, including patients with chronic cervical SCI with complete and incomplete injury aged over 14 years and age-/sex-matched healthy participants. Outcome measures include BCI control and performance in the BMI-SG module, as well as improvement of functional independence, while also monitoring neuropsychological parameters such as kinesthetic imagery, motivation, self-esteem, depression and anxiety, mental effort, discomfort, and perception of robotics. Participant enrollment into the main clinical trial is estimated to begin in January 2023 and end by December 2023. RESULTS: A preliminary analysis of collected data during pilot testing of BMI-SG by healthy participants showed that the platform was easy to use, caused no discomfort, and the robotics were perceived positively by the participants. Analysis of results from the main clinical trial will begin as recruitment progresses and findings from the complete analysis of results are expected in early 2024. CONCLUSIONS: Chronic SCI is characterized by irreversible disability impacting functional independence. NeuroSuitUp could provide a valuable complementary platform for training in immersive rehabilitation methods to promote dormant neural plasticity. TRIAL REGISTRATION: ClinicalTrials.gov NCT05465486; https://clinicaltrials.gov/ct2/show/NCT05465486. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/41152.

3.
Phys Chem Chem Phys ; 21(2): 729-735, 2019 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-30543328

RESUMO

Planar and quasi-planar boron clusters with a disk-like shape are investigated in search of common bonding characteristics. Methods used involve molecular orbital calculations based on Density Functional Theory (DFT), and valence bond partitioning using Adaptive Natural Density Partitioning (AdNDP) analysis. For high-symmetry cases the proposed bonding schemes are confirmed using the group-theoretical induction method. The focus is on the electron occupation of delocalized in-plane 3-center and 4-center bonds. For disks consisting of concentric rings this inner electron count is found to be equal to a multiple of the vertex count of the inner polygon. For two concentric rings the multiplying factor is four, for three concentric rings it is eight. The appropriate bonding schemes are presented which explain these results. Some giant clusters with two hexagonal holes are also discussed.

4.
J Med Microbiol ; 67(3): 400-407, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29458550

RESUMO

PURPOSE: To determine the predominant strains of Bordetella pertussis in Greece during 2010-2015. METHODOLOGY: Infants and children (n=1150) (15 days to 14 years) of Greek, Roma and immigrant origin with different vaccination statuses were hospitalized in Athens, Greece with suspected pertussis infection. IS481/IS1001 real-time PCR confirmed Bordetella spp./B. pertussis infection in 300 samples. A subset of samples (n=153) were analysed by multi-locus variable number tandem repeat analysis (MLVA) and (n=25) by sequence-based typing of the toxin promotor region (ptxP) on DNA extracted from clinical specimens.Results/Key findings. A complete MLVA profile was determined in 66 out of 153 samples; the B. pertussis MLVA type 27 (n=55) was the dominant genotype and all tested samples (n=25) expressed the ptxP3 genotype. The vaccine coverage in the Greek population was 90 %; however, the study population expressed complete coverage in 2 out of 264 infants (0-11 months) and in 20 out of 36 children (1-14 years). Roma and immigrant minorities represent 7 % of the Greek population, but make up 50 % of the study population, indicating a low vaccine coverage among these groups. CONCLUSIONS: The B. pertussis MT27 and ptxP3 genotype is dominant in Greek, Roma and immigrant infants and children hospitalized in Greece. Thus, the predominant MLVA genotype in Greece is similar to other countries using acellular vaccines.


Assuntos
Bordetella pertussis/genética , Coqueluche/epidemiologia , Coqueluche/microbiologia , Adolescente , Bordetella pertussis/isolamento & purificação , Criança , Pré-Escolar , DNA Bacteriano/genética , Feminino , Variação Genética , Genótipo , Grécia/epidemiologia , Hospitais Pediátricos , Humanos , Lactente , Recém-Nascido , Masculino , Repetições Minissatélites , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Coqueluche/diagnóstico , Coqueluche/etnologia
5.
J Phys Chem A ; 121(38): 7246-7254, 2017 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-28850228

RESUMO

The E ⊗ e Jahn-Teller Hamiltonian in the Bargmann-Fock representation gives rise to a system of two coupled first-order differential equations in the complex field, which may be rewritten in the Birkhoff standard form. General leapfrog recurrence relations are derived, from which the quantized solutions of these equations can be obtained. The results are compared to the analogous quantization scheme for the Rabi Hamiltonian.

6.
Phys Chem Chem Phys ; 16(34): 18311-8, 2014 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-25059906

RESUMO

This article presents the use of free particle models to obtain quantum rules for planar boron clusters, with nuclearities in the range from seven to twenty. The information obtained from the models is being compared with electronic structure calculations based on the DFT method. Separate rules for in-plane and out-of-plane bonding are derived. In-plane bonding is precise on the cluster boundary and forms a network of alternating triangular 3c-2e bonds on the inside. The out-of-plane bonding is strongly delocalized and only depends on the global shape and size of the cluster.

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