86,748 research outputs found
Sleep Quality through Vocal Analysis: a Telemedicine Application
No full textVoice is a reservoir of valuable health data. Recent studies highlighted its efficacy in predicting sleep quality, and its potential as biomarker of neurodegeneration. This study assesses the feasibility of a Telemedicine system for the evaluation of sleep quality through brief vocal recordings. Machine Learning models were employed in the binary classification between good and poor sleepers, with great performance in scoring poor sleep quality - 88% and 85% F-1 score on a 5-fold Cross Validation (CV) for females and males, respectively. Moreover, the correlation between perceived sleep quality and a validated global score was studied, as well as the influence of external factors and sleep-wake schedule
Wearable Sensors for Supporting Diagnosis, Prognosis, and Monitoring of Neurodegenerative Diseases
No full textPredicting Axial Impairment in Parkinson’s Disease through a Single Inertial Sensor
No full textBackground: Current telemedicine approaches lack standardised procedures for the remote assessment of axial impairment in Parkinson’s disease (PD). Unobtrusive wearable sensors may be a feasible tool to provide clinicians with practical medical indices reflecting axial dysfunction in PD. This study aims to predict the postural instability/gait difficulty (PIGD) score in PD patients by monitoring gait through a single inertial measurement unit (IMU) and machine-learning algorithms. Methods: Thirty-one PD patients underwent a 7-m timed-up-and-go test while monitored through an IMU placed on the thigh, both under (ON) and not under (OFF) dopaminergic therapy. After pre-processing procedures and feature selection, a support vector regression model was implemented to predict PIGD scores and to investigate the impact of L-Dopa and freezing of gait (FOG) on regression models. Results: Specific time-and frequency-domain features correlated with PIGD scores. After optimizing the dimensionality reduction methods and the model parameters, regression algorithms demonstrated different performance in the PIGD prediction in patients OFF and ON therapy (r = 0.79 and 0.75 and RMSE = 0.19 and 0.20, respectively). Similarly, regression models showed different performances in the PIGD prediction, in patients with FOG, ON and OFF therapy (r = 0.71 and RMSE = 0.27; r = 0.83 and RMSE = 0.22, respectively) and in those without FOG, ON and OFF therapy (r = 0.85 and RMSE = 0.19; r = 0.79 and RMSE = 0.21, respectively). Conclusions: Optimized support vector regression models have high feasibility in predicting PIGD scores in PD. L-Dopa and FOG affect regression model performances. Overall, a single inertial sensor may help to remotely assess axial motor impairment in PD patients
Edge-based freezing of gait recognition in Parkinson's disease
No full textFreezing of gait (FoG) stands as one of the most debilitating symptoms of Parkinson's disease (PD), occurring in more than half of patients with advanced PD. This condition manifests as a sudden blockage, significantly reducing the patients’ quality of life. To improve gait and ameliorate FoG, cueing strategies involving audio, visual, or tactile stimulation have been evaluated. In particular, on-demand systems that can automatically detect FoG and administer cueing have emerged as promising solutions. In response, several wearable sensors and machine learning-based approaches have been proposed for accurate FoG recognition. However, existing techniques suffer from several critical challenges, notably suboptimal performance, and limitations for real-time operation and edge deployment. Addressing these issues, this study presents a groundbreaking advancement in real-time edge-based FoG recognition utilizing convolutional neural networks (CNN). We designed an optimized model, rigorously evaluating it across 62 PD patients using a cutting-edge reference dataset, achieving an F1-score of 92% and an area under the curve of 0.97. Further testing on an external dataset resulted in consistent detection performance, while a lower specificity was observed. The CNN implementation on a cost-effective processing device resulted in a 1 ms inference time and required only 6.3 KB of random access memory (RAM) and 37.8 KB of Flash memory, meeting real-time demands and enhancing clinical applicability
Functional assessment of the collateral-dependent circulation in chronic total coronary occlusion using transthoracic Doppler ultrasound and venous adenosine infusion
No full textThe measurement of collateral flow reserve (CFR; the hyperemic/baseline collateral flow velocity ratio) in patients with chronic total coronary occlusion requires invasive and expensive techniques. Noninvasive transthoracic coronary Doppler echocardiography may be an alternative option. Fifty-one patients with chronic total coronary occlusion were evaluated by transthoracic coronary Doppler echocardiography and venous adenosine infusion to measure CFR in occluded coronary arteries (the left anterior descending artery in 44 patients and the artery supplying the posterior descending artery in 7 patients). CFR data were plotted against 3 angiographic parameters: (1) grade of the epicardial filling of the occluded artery (1=absent, 2=partial, 3=complete), (2) stenosis of the donor artery, and (3) the extent of coronary artery disease (vessels with >or=70% stenosis). Collateral flow was maintained at stress in 34 patients (CFR>or=1, range 1.0 to 2.2) but was withdrawn in 17 patients (CFR<1, range 0.25 to 0.90). CFR increased with the degree of angiographic collateral flow (grade 1: 0.73+/-0.29; grade 2: 1.16+/-0.31; grade 3: 1.34+/-0.49; F=5.31, p=0.008). A multivariate model of CFR prediction showed a direct relation with angiographic collateral grade and the number of diseased vessels and an inverse relation with stenosis of the donor artery. In conclusion, CFR measurement is feasible by transthoracic coronary Doppler echocardiography. One third of the patients with chronic total coronary occlusion had collateral flow withdrawal at stress, which occurs when collateral circulation is poor and when the donor artery is stenotic. CFR correlates with angiographic collateral grade and with the extent of coronary artery disease
Polyamide modified with green tea extract for fresh minced meat active packaging applications
No full textNew antioxidant polyamide was prepared by total immersion in active extract for 48 h. Its antioxidant performance was tested using DPPH (IC50 = 270 ± 21 μg/g) and ORAC (1.52 μmol Trolox/g). In vivo study was done using fresh minced meat stored at 4 °C and analysed after 0, 6, 13, 19, 23 days. After 23 days metmyoglobin (MetMbBK = 31.3 ± 2.9% and MetMbAOX = 25.9 ± 0.8%), CIE L*a*b* (a*BK = 15.0 ± 0.4 and a*AOX = 16.6 ± 0.3) and TBARS (MDABK = 0.0060 ± 0.0003 μg/g and MDAAOX = 0.0044 ± 0.0002 μg/g) showed an improvement of meat shelf life. The results showed that this active film protected meat during 23 days. Migration study to food simulants was done by UPLC®-QqQ-MS and UPLC®-ESI-Q-TOF-MSE. A decrease of oligomers migration (for caprolactam n = 3: BK = 0.050 ± 0.004 mg/Kg; AOX = 0.019 ± 0.001 mg/Kg) was found. Industrial relevance: Nowadays, food industry is focused on improving shelf life of products by controlling its lipid oxidation using natural antioxidants. The obtained results let us design a new active packaging based on natural antioxidants for extending the shelf life of fresh minced meat at industrial scale
The extracapsular dissection technique in the management of benign tumors of the parotid gland: our experience in 194 patients
No full textObjective: The indications for and approaches to extracapsular dissection for parotid gland benign tumours are debated in the literature. This study retrospectively evaluates a single site's short- and long-term results with a standardised extracapsular dissection approach to benign parotid tumours. Methods: A retrospective review of a single institution's records identified cases with extracapsular dissection as the primary surgery for non-recurrent benign parotid tumours. A total of 194 eligible patients were identified (124 women and 70 men, age 47.75 ± 15.62 years). Pre-, intra- and post-surgical data were reviewed for complications and recurrences. Results: Histology reported pleomorphic adenoma in 165 patients, Warthin's tumour in 28 patients and both in one patient. Mean follow up was 36 ± 16 months (range, 12-84 months). The incidences of complications following extracapsular dissection were temporary (n = 13) and permanent (n = 0) facial nerve dysfunction, Frey's syndrome (n = 1)) and recurrences (n = 5). These rates align with prior literature. Conclusion: This case series shows how a standardised approach to extracapsular dissection for benign parotid tumours yields favourable results, supporting a progressive change of strategy towards reduced invasiveness
Nash Equilibria and Bargaining Solutions of Differential Bilinear Games
No full textThis paper is devoted to a theoretical and numerical investigation of Nash equilibria and Nash bargaining problems governed by bilinear (input-affine) differential models. These systems with a bilinear state-control structure arise in many applications in, e.g., biology, economics, physics, where competition between different species, agents, and forces needs to be modelled. For this purpose, the concept of Nash equilibria (NE) appears appropriate, and the building blocks of the resulting differential Nash games are different control functions associated with different players that pursue different non-cooperative objectives. In this framework, existence of Nash equilibria is proved and computed with a semi-smooth Newton scheme combined with a relaxation method. Further, a related Nash bargaining (NB) problem is discussed. This aims at determining an improvement of all players’ objectives with respect to the Nash equilibria. Results of numerical experiments successfully demonstrate the effectiveness of the proposed NE and NB computational framework.publishe
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Cryptogenic cerebral ischemia: clinical usefulness of a flexible ultrasound diagnostic algorithm for detection of patent foramen ovale
No full textParadoxical thromboembolism across a patent foramen ovale (PFO) may be involved in the pathogenesis of cryptogenic strokes. We tested the feasibility and the clinical usefulness of an early screening for PFO combining different ultrasound techniques in patients with acute cerebral ischemia of undetermined cause
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