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1.
Comput Biol Med ; 159: 106741, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37105109

RESUMO

Mental disorders are rapidly increasing each year and have become a major challenge affecting the social and financial well-being of individuals. There is a need for phenotypic characterization of psychiatric disorders with biomarkers to provide a rich signature for Major Depressive Disorder, improving the understanding of the pathophysiological mechanisms underlying these mental disorders. This comprehensive review focuses on depression and relapse detection modalities such as self-questionnaires, audiovisuals, and EEG, highlighting noteworthy publications in the last ten years. The article concentrates on the literature that adopts machine learning by audiovisual and EEG signals. It also outlines preprocessing, feature extraction, and public datasets for depression detection. The review concludes with recommendations that will help improve the reliability of developed models and the determinism of computational intelligence-based systems in psychiatry. To the best of our knowledge, this survey is the first comprehensive review on depression and relapse prediction by self-questionnaires, audiovisual, and EEG-based approaches. The findings of this review will serve as a useful and structured starting point for researchers studying clinical and non-clinical depression recognition and relapse through machine learning-based approaches.


Assuntos
Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/diagnóstico , Depressão/diagnóstico , Reprodutibilidade dos Testes , Aprendizado de Máquina , Eletroencefalografia
2.
Build Simul ; 16(2): 225-241, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36277844

RESUMO

The temperature distribution is always assumed to be homogeneous in a traditional single-input-single-output (SISO) air conditioning control strategy. However, the airflow inside is more complicated and unpredictable. This study proposes a zonal temperature control strategy with a thermal coupling effect integrated for air-conditioned large-scale open spaces. The target space was split into several subzones based on the minimum controllable air terminal units in the proposed method, and each zone can be controlled to its own set-point while considering the thermal coupling effect from its adjacent zones. A numerical method resorting to computational fluid dynamics was presented to obtain the heat transfer coefficients (HTCs) under different air supply scenarios. The relationship between heat transfer coefficient and zonal temperature difference was linearized. Thus, currently available zonal models in popular software can be used to simulate the dynamic response of temperatures in large-scale indoor open spaces. Case studies showed that the introduction of HTCs across the adjacent zones was capable of enhancing the precision of temperature control of large-scale open spaces. It could satisfy the temperature requirements of different zones, improve thermal comfort and at least 11% of energy saving can be achieved by comparing with the conventional control strategy. Electronic Supplementary Material ESM: The Appendix is available in the online version of this article at 10.1007/s12273-022-0942-8.

3.
Healthcare (Basel) ; 10(11)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36421621

RESUMO

Mobility and low energy consumption are considered the main requirements for wireless body area sensor networks (WBASN) used in healthcare monitoring systems (HMS). In HMS, battery-powered sensor nodes with limited energy are used to obtain vital statistics about the body. Hence, energy-efficient schemes are desired to maintain long-term and steady connectivity of the sensor nodes. A sheer amount of energy is consumed in activities such as idle listening, excessive transmission and reception of control messages, packet collisions and retransmission of packets, and poor path selection, that may lead to more energy consumption. A combination of adaptive scheduling with an energy-efficient protocol can help select an appropriate path at a suitable time to minimize the control overhead, energy consumption, packet collision, and excessive idle listening. This paper proposes a region-based energy-efficient multipath routing (REMR) approach that divides the entire sensor network into clusters with preferably multiple candidates to represent each cluster. The cluster representatives (CRs) route packets through various clusters. For routing, the energy requirement of each route is considered, and the path with minimum energy requirements is selected. Similarly, end-to-end delay, higher throughput, and packet-delivery ratio are considered for packet routing.

4.
J Microsc ; 288(2): 106-116, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-33128278

RESUMO

Adaptive optics is being applied widely to a range of microscopies in order to improve imaging quality in the presence of specimen-induced aberrations. We present here the first implementation of wavefront-sensorless adaptive optics for a laser-free, aperture correlation, spinning disk microscope. This widefield method provides confocal-like optical sectioning through use of a patterned disk in the illumination and detection paths. Like other high-resolution microscopes, its operation is compromised by aberrations due to refractive index mismatch and variations within the specimen. Correction of such aberrations shows improved signal level, contrast and resolution.


Assuntos
Microscopia , Óptica e Fotônica , Refratometria , Lasers
5.
Comput Methods Programs Biomed ; 202: 106007, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33657466

RESUMO

Mental disorders represent critical public health challenges as they are leading contributors to the global burden of disease and intensely influence social and financial welfare of individuals. The present comprehensive review concentrate on the two mental disorders: Major depressive Disorder (MDD) and Bipolar Disorder (BD) with noteworthy publications during the last ten years. There is a big need nowadays for phenotypic characterization of psychiatric disorders with biomarkers. Electroencephalography (EEG) signals could offer a rich signature for MDD and BD and then they could improve understanding of pathophysiological mechanisms underling these mental disorders. In this review, we focus on the literature works adopting neural networks fed by EEG signals. Among those studies using EEG and neural networks, we have discussed a variety of EEG based protocols, biomarkers and public datasets for depression and bipolar disorder detection. We conclude with a discussion and valuable recommendations that will help to improve the reliability of developed models and for more accurate and more deterministic computational intelligence based systems in psychiatry. This review will prove to be a structured and valuable initial point for the researchers working on depression and bipolar disorders recognition by using EEG signals.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Transtorno Bipolar/diagnóstico , Transtorno Depressivo Maior/diagnóstico , Eletroencefalografia , Humanos , Redes Neurais de Computação , Reprodutibilidade dos Testes
6.
Sci Rep ; 9(1): 19910, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882787

RESUMO

Saturable Absorber (SA) is a key element of any passive mode-locked laser system to provide ultrashort laser system. So far various materials have been proposed that could be used for this purpose. However, the field is still looking for new ways to make the fabrication process easier and cost-effective. Another challenge in testing mode-locked laser systems using various SA samples is the lack of knowledge in preparing these by laser physicists given this is outside their remit of expertise. In this study, we have proposed a novel method to produce these SAs from plastic materials and glycol. Our new method relies upon increase in thickness up to a value where the modulation depth is enough to give stable ultrashort pulses. Although we have shown this method for four materials; similar approach could be applied to any material. This will open the door of unlimited families of SAs that could be easily prepared and applied without any prior knowledge in material sciences.

7.
Sci Rep ; 9(1): 17282, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31754225

RESUMO

Graphene (Gr) and Carbon nanotube (CNT) saturable absorbers (SAs) are considered as broadband absorbers and have been used in various studies in the past to get a broad wavelength and pulse duration tunable laser. However, the literature lacks a comparative study on these SAs where one will continue to give longer pulses than the other. In this paper we have compared these two SAs and provided a guideline on how to design them for tunable operation. The parameters that have been compared in this research can be used for other broad gain materials and SAs.

8.
Graefes Arch Clin Exp Ophthalmol ; 255(5): 945-953, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28101654

RESUMO

PURPOSE: Some forms of keratoplasty assisted by ultrashort-pulse lasers require performing laser cuts close to the endothelium, which requires the knowledge of "safe" values concerning incision depth and pulse energy preserving endothelial cell viability. Our study aims to determine the thresholds for cell death in porcine corneas exposed to ultrashort laser pulses, in terms of laser pulse energy and nearness of the impacts to the endothelium. METHODS: Using a laboratory laser set-up, lamellar cuts were induced while varying pulse energies and distances from the endothelium. A fluorescent staining protocol was used to determine the percentage of surviving endothelial cells. Numerical simulations of the Euler equations for compressible fluids provided pressure level and axial and radial pressure gradient estimates at the endothelium. RESULTS: Ninety percent of the endothelial cells survived when using 16.5 µJ pulses no closer than 200 µm to the endothelium, or pulses not exceeding 2 µJ at a distance of 50 µm. The comparison of the observed percentage of surviving cells with the estimates of the shock wave amplitudes and gradients generated by the laser pulses yielded cell death thresholds at amplitudes in the megapascal range, or gradients of the order of 108 Pa/m. CONCLUSIONS: Our results provide limits in terms of pulse energy and distance of the incision from the endothelium within which endothelial cell viability is preserved. Current forms of corneal laser surgery are compatible with these limits. However, these limits will need to be considered for the development of future laser routines working in close proximity to the endothelium.


Assuntos
Cirurgia da Córnea a Laser/métodos , Endotélio Corneano/ultraestrutura , Animais , Morte Celular , Sobrevivência Celular , Endotélio Corneano/cirurgia , Microscopia Eletrônica de Varredura , Modelos Animais , Suínos , Tomografia de Coerência Óptica
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