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1.
Sensors (Basel) ; 24(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38610437

RESUMO

Computer vision (CV)-based systems using cameras and recognition algorithms offer touchless, cost-effective, precise, and versatile hand tracking. These systems allow unrestricted, fluid, and natural movements without the constraints of wearable devices, gaining popularity in human-system interaction, virtual reality, and medical procedures. However, traditional CV-based systems, relying on stationary cameras, are not compatible with mobile applications and demand substantial computing power. To address these limitations, we propose a portable hand-tracking system utilizing the Leap Motion Controller 2 (LMC) mounted on the head and controlled by a single-board computer (SBC) powered by a compact power bank. The proposed system enhances portability, enabling users to interact freely with their surroundings. We present the system's design and conduct experimental tests to evaluate its robustness under variable lighting conditions, power consumption, CPU usage, temperature, and frame rate. This portable hand-tracking solution, which has minimal weight and runs independently of external power, proves suitable for mobile applications in daily life.


Assuntos
Antebraço , Dispositivos Eletrônicos Vestíveis , Humanos , Extremidade Superior , Mãos , Algoritmos
2.
Sensors (Basel) ; 23(7)2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-37050523

RESUMO

Telerehabilitation is important for post-stroke or post-surgery rehabilitation because the tasks it uses are reproducible. When combined with assistive technologies, such as robots, virtual reality, tracking systems, or a combination of them, it can also allow the recording of a patient's progression and rehabilitation monitoring, along with an objective evaluation. In this paper, we present the structure, from actors and functionalities to software and hardware views, of a novel framework that allows cooperation between patients and therapists. The system uses a computer-vision-based system named virtual glove for real-time hand tracking (40 fps), which is translated into a light and precise system. The novelty of this work lies in the fact that it gives the therapist quantitative, not only qualitative, information about the hand's mobility, for every hand joint separately, while at the same time providing control of the result of the rehabilitation by also quantitatively monitoring the progress of the hand mobility. Finally, it also offers a strategy for patient-therapist interaction and therapist-therapist data sharing.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Telerreabilitação , Humanos , Interface Usuário-Computador , Mãos , Extremidade Superior , Software
3.
Comput Biol Med ; 132: 104347, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33799218

RESUMO

BACKGROUND AND OBJECTIVES: Electroencephalography (EEG) measures the electrical brain activity in real-time by using sensors placed on the scalp. Artifacts due to eye movements and blinking, muscular/cardiac activity and generic electrical disturbances, have to be recognized and eliminated to allow a correct interpretation of the Useful Brain Signals (UBS). Independent Component Analysis (ICA) is effective to split the signal into Independent Components (IC) whose re-projection on 2D topographies of the scalp (images also called Topoplots) allows to recognize/separate artifacts and UBS. Topoplot analysis, a gold standard for EEG, is usually carried out offline either visually by human experts or through automated strategies, both unenforceable when a fast response is required as in online Brain-Computer Interfaces (BCI). We present a fully automatic, effective, fast, scalable framework for artifacts recognition from EEG signals represented in IC Topoplots to be used in online BCI. METHODS: The proposed architecture, optimized to contain three 2D Convolutional Neural Networks (CNN), divides Topoplots in 4 classes: 3 types of artifacts and UBS. The framework architecture is described and the results are presented, discussed and indirectly compared with those obtained from state-of-the-art competitive strategies. RESULTS: Experiments on public EEG datasets showed overall accuracy, sensitivity and specificity greater than 98%, taking 1.4 s on a standard PC for 32 Topoplots, i.e. for an EEG system with at least 32 sensors. CONCLUSIONS: The proposed framework is faster than other automatic methods based on IC analysis and fast enough to be used in EEG-based online BCI. In addition, its scalable architecture and ease of training are necessary conditions to apply it in BCI, where difficult operating conditions caused by uncontrolled muscle spasms, eye rotations or head movements, produce specific artifacts that need to be recognized and dealt with.


Assuntos
Artefatos , Couro Cabeludo , Algoritmos , Piscadela , Encéfalo , Eletroencefalografia , Humanos , Processamento de Sinais Assistido por Computador
4.
World J Mens Health ; 39(4): 750-759, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33474849

RESUMO

PURPOSE: Osteoporosis affects more than 200 million people worldwide: its prevalence increases with age and is actually growing due to the constant population aging. Women are at greater risk than men, but in recent years it has become increasingly evident that osteoporosis represents a significantly important problem also for men. However, osteoporosis in men is still poorly studied, underdiagnosed and inadequately treated. MATERIALS AND METHODS: We conducted an observational study to identify any gender disparities in osteoporosis screening. For this purpose we observed people consecutively admitted at our Outpatient Service for the Diagnosis of Osteoporosis during the last 3 years. Patients underwent clinical and laboratory assessment and bone mineral density (BMD) measurements by dual-energy X-ray absorptiometry. Bone turnover serum markers have been evaluated and stratified according to gender. RESULTS: Out of 3,752 patients, 2,376 subjects who met the inclusion criteria were identified. As expected, the great majority (94.5%) of the screened subjects were women and only 5.4% were men. Women exhibited lower BMD compared to men (T-score values: -2.33±1.14 vs. -1.31±1.55; p<0.001), whereas the prevalence of fractures in osteoporotic men was significantly higher (50% vs. 31%; p<0.001). Women had lower vitamin D and higher bone remodeling markers compared to men. Secondary osteoporosis was more frequent in men (66.67%) than in women (20.83%) and the calculated risk for hip fractures was higher in osteoporotic men compared to women (11.47±10.62 vs. 6.87±7.73; p<0.001). CONCLUSIONS: Here we highlighted that men are under-screened for osteoporosis and exhibit secondary osteoporosis more frequently than women.

5.
Pattern Recognit Lett ; 140: 95-100, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33041409

RESUMO

Computer Tomography (CT) imaging of the chest is a valid diagnosis tool to detect COVID-19 promptly and to control the spread of the disease. In this work we propose a light Convolutional Neural Network (CNN) design, based on the model of the SqueezeNet, for the efficient discrimination of COVID-19 CT images with respect to other community-acquired pneumonia and/or healthy CT images. The architecture allows to an accuracy of 85.03% with an improvement of about 3.2% in the first dataset arrangement and of about 2.1% in the second dataset arrangement. The obtained gain, though of low entity, can be really important in medical diagnosis and, in particular, for Covid-19 scenario. Also the average classification time on a high-end workstation, 1.25 s, is very competitive with respect to that of more complex CNN designs, 13.41 s, witch require pre-processing. The proposed CNN can be executed on medium-end laptop without GPU acceleration in 7.81 s: this is impossible for methods requiring GPU acceleration. The performance of the method can be further improved with efficient pre-processing strategies for witch GPU acceleration is not necessary.

6.
Brain Sci ; 10(4)2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32235515

RESUMO

3M syndrome is a rare disorder that involves the gene cullin-7 (CUL7). CUL7 modulates odour detection, conditions the olfactory response (OR) and plays a role in the development of the olfactory system. Despite this involvement, there are no direct studies on olfactory functional effects in 3M syndrome. The purpose of the present work was to analyse the cortical OR through chemosensory event-related potentials (CSERPs) and power spectra calculated by electroencephalogram (EEG) signals recorded in 3M infants: two twins (3M-N) and an additional subject (3M-O). The results suggest that olfactory processing is diversified. Comparison of N1 and Late Positive Component (LPC) indicated substantial differences in 3M syndrome that may be a consequence of a modified olfactory processing pattern. Moreover, the presence of delta rhythms in 3M-O and 3M-N clearly indicates their involvement with OR, since the delta rhythm is closely connected to chemosensory perception, in particular to olfactory perception.

7.
Sensors (Basel) ; 18(3)2018 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-29534448

RESUMO

Hand rehabilitation is fundamental after stroke or surgery. Traditional rehabilitation requires a therapist and implies high costs, stress for the patient, and subjective evaluation of the therapy effectiveness. Alternative approaches, based on mechanical and tracking-based gloves, can be really effective when used in virtual reality (VR) environments. Mechanical devices are often expensive, cumbersome, patient specific and hand specific, while tracking-based devices are not affected by these limitations but, especially if based on a single tracking sensor, could suffer from occlusions. In this paper, the implementation of a multi-sensors approach, the Virtual Glove (VG), based on the simultaneous use of two orthogonal LEAP motion controllers, is described. The VG is calibrated and static positioning measurements are compared with those collected with an accurate spatial positioning system. The positioning error is lower than 6 mm in a cylindrical region of interest of radius 10 cm and height 21 cm. Real-time hand tracking measurements are also performed, analysed and reported. Hand tracking measurements show that VG operated in real-time (60 fps), reduced occlusions, and managed two LEAP sensors correctly, without any temporal and spatial discontinuity when skipping from one sensor to the other. A video demonstrating the good performance of VG is also collected and presented in the Supplementary Materials. Results are promising but further work must be done to allow the calculation of the forces exerted by each finger when constrained by mechanical tools (e.g., peg-boards) and for reducing occlusions when grasping these tools. Although the VG is proposed for rehabilitation purposes, it could also be used for tele-operation of tools and robots, and for other VR applications.


Assuntos
Luvas Protetoras , Mãos , Força da Mão , Humanos , Reabilitação do Acidente Vascular Cerebral , Interface Usuário-Computador , Realidade Virtual
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