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1.
Artigo em Inglês | MEDLINE | ID: mdl-39021157

RESUMO

The classification of inter-patient ECG data for arrhythmia detection using electrocardiogram (ECG) signals presents a significant challenge. Despite the recent surge in deep learning approaches, there remains a noticeable gap in the performance of inter-patient ECG classification. In this study, we introduce an innovative approach for ECG classification in arrhythmia detection by employing a 1D convolutional neural network (CNN) to leverage both morphological and temporal characteristics of cardiac cycles. Through the utilization of 1D-CNN layers, we automatically capture the morphological attributes of ECG data, allowing us to represent the shape of the ECG waveform around the R peaks. Additionally, we incorporate four RR interval features to provide temporal context, and we explore the potential application of entropy rate as a feature extraction technique for ECG signal classification. Consequently, the classification layers benefit from the combination of both temporal and learned features, leading to the achievement of the final arrhythmia classification. We validate our approach using the MIT-BIH arrhythmia dataset, employing both intra-patient and inter-patient paradigms for model training and testing. The model's generalization ability is assessed by evaluating it on the INCART dataset. The model attains average accuracy rates of 99.13% and 99.17% for 2-fold and 5-fold cross-validation, respectively, in intra-patient classification with five classes. In inter-patient classification with three and five classes, the model achieves average accuracies of 98.73% and 97.91%, respectively. For the INCART dataset, the model achieves an average accuracy of 98.20% for three classes. The experimental outcomes demonstrate the superiority of the proposed model compared to state-of-the-art models in recognizing arrhythmias. Thus, the proposed model exhibits enhanced generalization and the potential to serve as an effective solution for recognizing arrhythmias in real-world datasets characterized by class imbalances in practical applications.

2.
Saf Health Work ; 11(2): 193-198, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32596015

RESUMO

BACKGROUND: Medical laboratory workers are frequently exposed to a wide range of chemicals. This exposure can have adverse effects on their health. Furthermore, a knowledge lack of the chemical risk increases the likelihood of exposure. The chemical risk assessment reduces the risk of exposure to hazardous chemicals and therefore, guarantees health and safety of the workers. METHOD: The chemical risk assessment was conducted using a modified INRS method, according to the new CLP Regulation, of 11 unit laboratories in a Moroccan medical laboratory. Observation of each workstation and analysis of safety data sheets are key tools in this study. RESULTS: A total of 144 substances and reagents that could affect the health of the analytical technicians were identified. Among these products, 17% are concerned by the low priority risk score, with 55% concerned by the average priority risk score and 28% concerned by the high priority risk score. This study also enabled to better identify the chemical agents that have restrictive occupational exposure limit value and controls were conducted to this effect. On the basis of the results obtained, several corrective and preventive measures have been proposed and implemented. CONCLUSION: Risk assessment is essential to ensure the health and safety of workers and to meet regulatory requirements. It enables to identify all the risky manipulations and to adopt appropriate preventive measures. However, it is not a one-time activity but it must be continuous in order to master the changes and thus ensure the best safety of all.

3.
Rev. bras. farmacogn ; 28(5): 575-581, Sept.-Oct. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-977733

RESUMO

Abstract Echinoderms have attracted the attention of scientists over the past few years after identifying a variety of unique structures endowed by interesting biological properties. However, the Moroccan coast biodiversity is still uninvestigated. In our ongoing attempts to valorize the rich Moroccan marine environment, this study aimed at assessing the antimicrobial activity of extracts obtained from three echinoderms Astropecten irregularis, Luidia sarsi and Ophiura albida against the human pathogens: Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica and Bacillus subtilis. Moreover, their antioxidant activities were tested using standard methods in addition to the antidiabetic activity which has been evaluated in vitro against α-amylase and α-glucosidase enzymes. HPLC-DAD-QTOF-MS analysis revealed a significant content of some phenolic compounds such as pyrogallol, gallic, sinapic, ferulic, p-hydroxybenzoic and salicylic acids whose existence can be related to the endophytic fungi and/or dietary intake whereas GC-MS analysis exhibited diverse chemical structures such as cholesterol, oleic acid and glycerol 1-palmitate.

4.
Front Robot AI ; 5: 88, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-33500967

RESUMO

Despite major progress in Robotics and AI, robots are still basically "zombies" repeatedly achieving actions and tasks without understanding what they are doing. Deep-Learning AI programs classify tremendous amounts of data without grasping the meaning of their inputs or outputs. We still lack a genuine theory of the underlying principles and methods that would enable robots to understand their environment, to be cognizant of what they do, to take appropriate and timely initiatives, to learn from their own experience and to show that they know that they have learned and how. The rationale of this paper is that the understanding of its environment by an agent (the agent itself and its effects on the environment included) requires its self-awareness, which actually is itself emerging as a result of this understanding and the distinction that the agent is capable to make between its own mind-body and its environment. The paper develops along five issues: agent perception and interaction with the environment; learning actions; agent interaction with other agents-specifically humans; decision-making; and the cognitive architecture integrating these capacities.

5.
Nat Prod Res ; 31(22): 2669-2674, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28152614

RESUMO

Scolymus hispanicus or the Golden Thistle, locally known as 'Guernina' or 'Taghediwt', is one of the most appreciated wild vegetables in Morocco. This study aims to characterise the functional chemical and pharmacological variability of Scolymus hispanicus parts (roots, stems, leaves and flowers). The chemical analysis revealed higher content of α-tocopherol in the flowers (2.79 ± 0.07 mg/100 g) and lead to the identification of 3 flavonoids and 13 phenolic acids, with high content of gallic acid in leaves (187.01 ± 10.19 mg/kg); chlorogenic (936.18 ± 92.66 mg/kg) and caffeic (4400.14 ± 191.43 mg/kg) acids in flowers, roots were much more higher in sinapic acid (0.25 ± 0.03 mg/kg) compared to the other parts. Moreover, Scolymus hispanicus ethanolic extracts exhibited interesting antioxidant and antimicrobial properties, promising anti-amylase and anti-glucosidase activities and relevant diuretic effect that confirms its traditional uses.


Assuntos
Flores/química , Folhas de Planta/química , Raízes de Plantas/química , Scolymus/química , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Diuréticos/química , Diuréticos/farmacologia , Flavonoides/análise , Ácido Gálico/análise , Hidroxibenzoatos/análise , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Marrocos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Caules de Planta , alfa-Tocoferol/análise
6.
Appl Ergon ; 42(6): 785-91, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21296335

RESUMO

In the context of task sharing between a robot companion and its human partners, the notions of safe and compliant hardware are not enough. It is necessary to guarantee ergonomic robot motions. Therefore, we have developed Human Aware Manipulation Planner (Sisbot et al., 2010), a motion planner specifically designed for human-robot object transfer by explicitly taking into account the legibility, the safety and the physical comfort of robot motions. The main objective of this research was to define precise subjective metrics to assess our planner when a human interacts with a robot in an object hand-over task. A second objective was to obtain quantitative data to evaluate the effect of this interaction. Given the short duration, the "relative ease" of the object hand-over task and its qualitative component, classical behavioral measures based on accuracy or reaction time were unsuitable to compare our gestures. In this perspective, we selected three measurements based on the galvanic skin conductance response, the deltoid muscle activity and the ocular activity. To test our assumptions and validate our planner, an experimental set-up involving Jido, a mobile manipulator robot, and a seated human was proposed. For the purpose of the experiment, we have defined three motions that combine different levels of legibility, safety and physical comfort values. After each robot gesture the participants were asked to rate them on a three dimensional subjective scale. It has appeared that the subjective data were in favor of our reference motion. Eventually the three motions elicited different physiological and ocular responses that could be used to partially discriminate them.


Assuntos
Mãos , Movimento , Robótica/métodos , Adulto , Eletromiografia , Movimentos Oculares/fisiologia , Feminino , Resposta Galvânica da Pele , Mãos/fisiologia , Força da Mão/fisiologia , Humanos , Masculino , Movimento/fisiologia , Postura/fisiologia , Tempo de Reação , Robótica/normas , Interface Usuário-Computador
7.
Fitoterapia ; 75(7-8): 774-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15567263

RESUMO

A new isoquinoline-N-oxide alkaloid was extracted from the alkaloid fraction of a methanol extract of the seeds of Calycotome villosa subsp. intermedia. Its structure was established as 1-hydroxymethyl-6,7-dimethoxyisoquinoline-N-oxide (1) by spectroscopic techniques and X-ray diffraction analysis.


Assuntos
Alcaloides/química , Fabaceae , Isoquinolinas/química , Fitoterapia , Extratos Vegetais/química , Cristalografia por Raios X , Humanos , Sementes
8.
Molecules ; 9(7): 568-73, 2004 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-18007456

RESUMO

The known flavonoid chrysin-7-O-(beta-D-glycopyranoside) (chrysin glucoside,1) as a major fraction and a new glycoside flavone, chrysin-7-O-beta-D-[(6"-acetyl)glycopyranoside] (2) were isolated from the flowers and leaves of Calycotome Villosa Subsp. Intermedia, They were identified by UV-Vis, 1R, (1)H-, (13)C-NMR and ESI-MS.


Assuntos
Flavonas/isolamento & purificação , Glicosídeos/isolamento & purificação , Magnoliopsida/química , Flavonas/química , Glicosídeos/química
9.
Molecules ; 9(8): 650-7, 2004 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-18007466

RESUMO

Two tetrahydroisoquinoline alkaloids were extracted from the alkaloid fraction of a methanol extract of the seeds of Calycotome Villosa Subsp. intermedia. Their structures were established as (R)-1-hydroxymethyl-7-8-dimethoxy-1,2,3,4-tetrahydro- isoquinoline (1) and (S)-7-hydroxymethyl-2-3-dimethoxy-7,8,9,10-tetrahydroisoquinoline chloride (2) by spectroscopic techniques and X-ray diffraction analysis.


Assuntos
Alcaloides/química , Alcaloides/isolamento & purificação , Magnoliopsida/química , Tetra-Hidroisoquinolinas/química , Tetra-Hidroisoquinolinas/isolamento & purificação , Cristalografia por Raios X , Modelos Moleculares
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