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1.
Quintessence Int ; 52(2): 132-137, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33433079

RESUMEN

The extraction of a tooth with root resorption can be a complicated procedure and can result in the removal of a significant amount of alveolar bone. In the anterior maxilla, esthetic rehabilitation of damaged sites with implant-supported crown could require multiple surgeries. Patients often ask for an alternative, and minimally invasive treatments are generally preferred. In this paper, a clinical case of implant-supported crown in a site affected by root resorption is described. Immediate implant was placed leaving some root fragments in the osteotomy site, thus avoiding invasive extractive surgeries. A minimally invasive flapless technique with a computer-guided implant placement procedure was used. After ?8 years, clinical and radiologic data were stable, gingival tissues around the implant appeared healthy, no dark translucency appeared through marginal gingiva around the implant, and there was no pathologic probing pocket depth ?or bleeding on probing. In the presence of root resorption and ankylosis, computer-guided surgery could be helpful to prepare a precise implant site through various tissues, such as partially resorbed root remnants. (Quintessence Int 2021;52:132-137; doi: 10.3290/j.qi.a45432).


Asunto(s)
Implantes Dentales de Diente Único , Implantes Dentales , Carga Inmediata del Implante Dental , Computadores , Coronas , Implantación Dental Endoósea , Prótesis Dental de Soporte Implantado , Estética Dental , Humanos , Maxilar/cirugía , Extracción Dental , Resultado del Tratamiento
3.
J Craniomaxillofac Surg ; 49(2): 84-92, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33376041

RESUMEN

OBJECTIVE: The aim of this retrospective and observational study was to compare the accuracy of two different virtual surgical planning (VSP) protocols, namely, the CASS method and the modified CASS method. MATERIALS AND METHODS: The patients underwent bimaxillary orthognathic surgery, planned using either the CASS method or the modified CASS method. Linear and angular discrepancies between the VSP outcome and postoperative outcome for both groups were compared for maxilla, mandible, and chin segments. Aside from the comparison between both groups, additional criteria were used to determine the accuracy of the protocol based on a linear and angular difference between planned and actual outcomes of less than 2 mm and 4°, respectively. The intergroup comparisons were performed by one-way ANOVA, with the level of significance set at 5%. RESULTS: A total of 21 patients, of both genders, were assigned into group I (n = 11), planned with the CASS method, and group II (n = 10), planned with the modified CASS method. Both the CASS and modified CASS methods presented similar accuracy with regard to linear differences for the maxilla, mandible, and chin segments, except for ΔX for the mandibular segment, where the modified CASS method showed slightly better accuracy. However, there was a statistically significant difference with regard to angular differences in the chin segment, with the CASS method shown to be the more accurate. Aside from Δpitch for the chin segment, no linear or angular differences exceeded 2 mm or 4°. CONCLUSION: Although statistically significant differences were found with regard to angular measurements in the chin segment, the accuracy of the modified CASS method for virtual planning can be considered as clinically equivalent, with a performance comparable to that of the CASS method.


Asunto(s)
Cirugía Ortognática , Procedimientos Quirúrgicos Ortognáticos , Cirugía Asistida por Computador , Computadores , Femenino , Humanos , Imagenología Tridimensional , Masculino , Planificación de Atención al Paciente , Estudios Retrospectivos
4.
Neural Netw ; 133: 11-20, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33091719

RESUMEN

In computational neuroscience, as well as in machine learning, neuromorphic devices promise an accelerated and scalable alternative to neural network simulations. Their neural connectivity and synaptic capacity depend on their specific design choices, but is always intrinsically limited. Here, we present a strategy to achieve structural plasticity that optimizes resource allocation under these constraints by constantly rewiring the pre- and postsynaptic partners while keeping the neuronal fan-in constant and the connectome sparse. In particular, we implemented this algorithm on the analog neuromorphic system BrainScaleS-2. It was executed on a custom embedded digital processor located on chip, accompanying the mixed-signal substrate of spiking neurons and synapse circuits. We evaluated our implementation in a simple supervised learning scenario, showing its ability to optimize the network topology with respect to the nature of its training data, as well as its overall computational efficiency.


Asunto(s)
Aprendizaje Automático , Redes Neurales de la Computación , Plasticidad Neuronal/fisiología , Neuronas/fisiología , Sinapsis/fisiología , Algoritmos , Computadores , Humanos
5.
J Healthc Eng ; 2020: 8838390, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33354310

RESUMEN

Background: With the outbreak of COVID-19, large-scale telemedicine applications can play an important role in the epidemic areas or less developed areas. However, the transmission of hundreds of megabytes of Sectional Medical Images (SMIs) from hospital's Intranet to the Internet has the problems of efficiency, cost, and security. This article proposes a novel lightweight sharing scheme for permitting Internet users to quickly and safely access the SMIs from a hospital using an Internet computer anywhere but without relying on a virtual private network or another complex deployment. Methods: A four-level endpoint network penetration scheme based on the existing hospital network facilities and information security rules was proposed to realize the secure and lightweight sharing of SMIs over the Internet. A "Master-Slave" interaction to the interactive characteristics of multiplanar reconstruction and maximum/minimum/average intensity projection was designed to enhance the user experience. Finally, a prototype system was established. Results: When accessing SMIs with a data size ranging from 251.6 to 307.04 MB with 200 kBps client bandwidth (extreme test), the network response time to each interactive request remained at approximately 1 s, the original SMIs were kept in the hospital, and the deployment did not require a complex process; the imaging quality and interactive experience were recognized by radiologists. Conclusions: This solution could serve Internet medicine at a low cost and may promote the diversified development of mobile medical technology. Under the current COVID-19 epidemic situation, we expect that it could play a low-cost and high-efficiency role in remote emergency support.


Asunto(s)
Seguridad Computacional , Diagnóstico por Imagen/instrumentación , Internet , Radiología/métodos , Algoritmos , Redes de Comunicación de Computadores , Computadores , Diagnóstico por Imagen/métodos , Diseño de Equipo , Hospitalización , Hospitales , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Informática Médica , Lenguajes de Programación , Telemedicina
6.
Zhonghua Nan Ke Xue ; 26(10): 895-899, 2020 Nov.
Artículo en Chino | MEDLINE | ID: mdl-33382220

RESUMEN

Objective: To investigate the application of the self-made semen quality control (QC) product in internal QC of computer-assisted sperm analysis (CASA). METHODS: CASA was calibrated with high- and low-concentration commercially available semen QC product and meanwhile 15 samples of self-made mixed semen QC product were placed in 75 cryotubes containing liquid nitrogen, followed by CASA of the concentration, motility, curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), linearity (LIN), wobble (WOB) and straightness (STR) of the sperm using standard procedures and 50 days of continuous monitoring. The Makler counting plate was used to measure the concentration and motility of the self-made sperm. RESULTS: The coefficients of variation (CV) of the commercially available semen QC product at high and low concentrations were 6.18% and 7.85%, respectively. CASA showed that the concentration of the self-made QC product was (25.97 ± 1.41) ×106/ml, with a CV of 5.42%, and the sperm motility, VCL, VSL, VAP, LIN, WOB and STR were (22.15 ± 1.75)% (CV = 7.9%), (59.18 ± 2.05) µm/s (CV = 3.46%), (26.79 ± 1.2) µm/s (CV = 4.48%), (34.98 ± 1.4) µm/s (CV = 4.01%), 46.81 ± 1.55 (CV = 3.3%), 60.52 ± 1.3 (CV = 2.15%) and 76.46 ± 1.98 (CV = 2.59%), respectively. The concentration and motility of the self-made sperm detected with the Makler counting plate were (34.39 ± 2.37) ×106/ml (CV = 6.89%) and (38.04 ± 1.69)% (CV = 4.44%), respectively. Levey-Jennings QC charts were plotted for the indicators using the means and standard deviation. CONCLUSIONS: The self-made internal QC product by liquid nitrogen cryopreservation is feasible and effective for monitoring the accuracy and precision of CASA-derived sperm concentration and motion parameters, and it has a smaller CV than the commercially available QC product in measuring sperm concentration.


Asunto(s)
Control de Calidad , Análisis de Semen/métodos , Análisis de Semen/normas , Motilidad Espermática , Computadores , Humanos , Masculino , Espermatozoides
7.
PLoS One ; 15(12): e0243926, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33332433

RESUMEN

A bilevel programming problem with multiple objectives at the leader's and/or follower's levels, known as a bilevel multiobjective programming problem (BMPP), is extraordinarily hard as this problem accumulates the computational complexity of both hierarchical structures and multiobjective optimisation. As a strongly NP-hard problem, the BMPP incurs a significant computational cost in obtaining non-dominated solutions at both levels, and few studies have addressed this issue. In this study, an evolutionary algorithm is developed using surrogate optimisation models to solve such problems. First, a dynamic weighted sum method is adopted to address the follower's multiple objective cases, in which the follower's problem is categorised into several single-objective ones. Next, for each the leader's variable values, the optimal solutions to the transformed follower's programs can be approximated by adaptively improved surrogate models instead of solving the follower's problems. Finally, these techniques are embedded in MOEA/D, by which the leader's non-dominated solutions can be obtained. In addition, a heuristic crossover operator is designed using gradient information in the evolutionary procedure. The proposed algorithm is executed on some computational examples including linear and nonlinear cases, and the simulation results demonstrate the efficiency of the approach.


Asunto(s)
Simulación por Computador , Computadores , Lenguajes de Programación , Algoritmos , Modelos Teóricos , Solución de Problemas
8.
Angle Orthod ; 90(3): 390-396, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33378429

RESUMEN

OBJECTIVES: To evaluate a new superimposition method compatible with computer-aided cephalometrics and to compare superimposition error to that of the conventional Sella-Nasion (SN) superimposition method. MATERIALS AND METHODS: A total of 283 lateral cephalometric radiographs were collected and cephalometric landmark identification was performed twice by the same examiner at a 3-month interval. The second tracing was superimposed on the first tracing by both the SN superimposition method and the new, proposed method. The proposed method not only relied on SN landmarks but also minimized the differences between four additional landmarks: Porion, Orbitale, Basion, and Pterygoid. The errors between the landmarks of the duplicate tracings oriented by the two superimposition methods were calculated at Anterior Nasal Spine, Point A, Point B, Pogonion, and Gonion. The paired t-test was used to find any statistical difference in the superimposition errors by the two superimposition methods and to investigate whether there existed clinically significant differences between the two methods. RESULTS: The proposed method demonstrated smaller superimposition errors than did the conventional SN superimposition method. When comparisons between the two superimposition methods were made with a 1-mm error range, there were clinically significant differences between them. CONCLUSIONS: The proposed method that was compatible with computer-aided cephalometrics might be a reliable superimposition method for superimposing serial cephalometric images.


Asunto(s)
Computadores , Cabeza , Cefalometría , Radiografía , Reproducibilidad de los Resultados
9.
Zhonghua Yan Ke Za Zhi ; 56(12): 920-927, 2020 Dec 11.
Artículo en Chino | MEDLINE | ID: mdl-33342118

RESUMEN

Objective: To develop a fundus image quality assessment system based on computer vision technology and to verify its accuracy by comparing the results of artificial discrimination and using this system. Methods: The process of image evaluation was divided into four modules: fundus image preprocessing, fundus image quality evaluation, fundus image content detection and evaluation result output. The system was designed to automatically evaluate the image quality of each fundus image, identify the optic disc and macula, and judge whether the image was qualified or not according to the image quality discrimination rules. A total of 2 397 fundus images of 787 type 2 diabetes patients were selected as the test data set. The average age of the patients, including 384 males and 403 females, was (69.65±19.09) years old. The images were taken by the staff of community health service centers in Shanghai with a fundus camera. The fundus image quality assessment system was used to conduct quality control and classification of the data set. At the same time, 12 professional fundus picture readers were employed to conduct manual quality control and classification of this data set. The system quality control results and artificial quality discrimination results were compared and analyzed. Results: The fundus image quality assessment system automatically recognized left and right eyes and eye positions on the input fundus images. The quality control interface included four indicator lights, which respectively corresponded to the images with the optic disc or macula as the center of the left or right eye. Evaluation of each fundus image was completed within 1 second, and the results were automatically displayed on the user interface. The 2 397 fundus photos were identified manually as 1 846 qualified photos and 551 unqualified photos. Among the unqualified images, 62 (11.27%) were too dark, 51 (9.27%) were too bright, 59 (10.73%) were not clear in the macular area, 36 (6.54%) showed no macula or optic disc, 125 (22.73%) could not present the fundus structure, 175 (31.82%) were blurred, and 42 (7.64%) were blocked. The results of the system and manual assessment were consistent in 1 788 qualified images (96.86%) and 550 unqualified images (99.82%), with an overall consistency rate of 97.54%. Conclusion: The fundus image quality assessment system can achieve highly consistent results with the professional judgment of ophthalmologists and has the characteristics of objectivity. (Chin J Ophthalmol, 2020, 56:920-927).


Asunto(s)
Diabetes Mellitus Tipo 2 , Anciano , Anciano de 80 o más Años , China , Computadores , Femenino , Fondo de Ojo , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Tecnología
10.
Compend Contin Educ Dent ; 41(10): 514-519; quiz 520, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33350841

RESUMEN

The use of dental implants to restore oral form and function has transformed the dental treatment of both partially and fully edentulous patients. With the advent of cone-beam computed tomography (CBCT) imaging technology in 1998 followed by its establishment at the beginning of the new century as the imaging modality of choice in implant treatment, 2-dimensional treatment planning was abruptly supplemented by the much-cherished third dimension. Additive manufacturing, ie, the fabrication of an object by adding material layer by layer, was pioneered in the early 1980s and has become readily available and relatively affordable over the past few years. Although computer-guided planning of treatment is gaining ground in implant therapy, freehand placement of the fixtures remains the standard of care. Time and cost considerations and lack of proper training throughout the steps involved are factors in why clinicians have been reluctant to adopt computer-guided placement of implants. The purpose of this article is to offer guidance to dental clinicians who favor freehand implant placement to facilitate their transition to computer-guided implantology with the use of static surgical guides.


Asunto(s)
Implantes Dentales , Cirugía Asistida por Computador , Diseño Asistido por Computadora , Computadores , Tomografía Computarizada de Haz Cónico , Implantación Dental Endoósea , Humanos , Imagenología Tridimensional , Planificación de Atención al Paciente
11.
Hipertens. riesgo vasc ; 37(4): 181-193, oct.-dic. 2020. tab
Artículo en Español | IBECS | ID: ibc-196908

RESUMEN

El creciente acceso y la alta eficacia del tratamiento antirretroviral han permitido que las personas que viven con el virus de la inmunodeficiencia humana alcancen una expectativa de vida semejante a la población general. Sin embargo, esta expectativa puede verse afectada por el aumento del riesgo de enfermedad cardiovascular en estos pacientes. Este riesgo es multifactorial, involucrando la elevada prevalencia de factores de riesgo cardiovascular tradicionales, el desarrollo de un estado proinflamatorio relacionado con la infección crónica y el uso de fármacos antirretrovirales con un perfil metabólico adverso. En la práctica clínica diaria disponemos de diferentes tablas y/o calculadoras para estimar el riesgo cardiovascular y orientar en la toma de decisiones médicas. La mayoría de estos surgen de estudios poblacionales en pacientes sin infección por el virus de la inmunodeficiencia humana. El objetivo de esta revisión es describir algunos determinantes de la enfermedad cardiovascular en personas que viven con el virus de la inmunodeficiencia humana, y la utilidad y aplicación de las calculadoras de riesgo cardiovascular en dichas personas


The increasing access and efficacy of antiretroviral therapy has allowed people living with human immunodeficiency virus to achieve a life expectancy similar to that of the general population. However, this goal may be affected by the increased risk of cardiovascular disease in this group. This risk is multifactorial, involving the high prevalence of traditional risk factors, the development of a pro-inflammatory state related to chronic infection, and the use of antiretroviral drugs with an adverse metabolic profile. In daily practice, in order to estimate this risk and guide medical decision-making, different calculators are available. These are based on data from population cohorts, many of them from human immunodeficiency virusnegative subjects. The main aim of this review is to describe the epidemiology of cardiovascular disease in people living with human immunodeficiency virus, the available risk calculators and their use


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Enfermedades Cardiovasculares/diagnóstico , Medición de Riesgo/métodos , Infecciones por VIH/epidemiología , Computadores , Terapia Antirretroviral Altamente Activa , Factores de Riesgo , Inmunoterapia Activa
14.
Nat Commun ; 11(1): 5795, 2020 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-33199682

RESUMEN

Chromosomes of all species studied so far display a variety of higher-order organisational features, such as self-interacting domains or loops. These structures, which are often associated to biological functions, form distinct, visible patterns on genome-wide contact maps generated by chromosome conformation capture approaches such as Hi-C. Here we present Chromosight, an algorithm inspired from computer vision that can detect patterns in contact maps. Chromosight has greater sensitivity than existing methods on synthetic simulated data, while being faster and applicable to any type of genomes, including bacteria, viruses, yeasts and mammals. Our method does not require any prior training dataset and works well with default parameters on data generated with various protocols.


Asunto(s)
Cromosomas/genética , Computadores , Reconocimiento de Normas Patrones Automatizadas , Algoritmos , Cromosomas Fúngicos/genética , Cromosomas Humanos/genética , Genoma Fúngico , Humanos , Saccharomyces cerevisiae/genética , Flujo de Trabajo
15.
Stud Health Technol Inform ; 273: 97-103, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-33087597

RESUMEN

Technological advancements in smart assistive technology enable navigating and manipulating various types of computer-aided devices in the operating room through a contactless gesture interface. Understanding surgeon actions is crucial to natural human-robot interaction in operating room since it means a sort of prediction a human behavior so that the robot can foresee the surgeon's intention, early choose appropriate action and reduce waiting time. In this paper, we present a new deep network based on Convolution Long Short-Term Memory (ConvLSTM) for gesture prediction configured to provide natural interaction between the surgeon and assistive robot and improve operating-room efficiency. The experimental results prove the capability of reliably recognizing unfinished gestures on videos. We quantitatively demonstrate the latter ability and the fact that GestureConvLSTM improves the baseline system performance on LSA64 dataset.


Asunto(s)
Gestos , Dispositivos de Autoayuda , Computadores , Humanos , Quirófanos , Interfaz Usuario-Computador
16.
Indian J Ophthalmol ; 68(11): 2378-2383, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33120622

RESUMEN

Purpose: Since the declaration of the lockdown due to COVID-19, the usage of digital devices has gone up across the globe, resulting in a challenge for the visual systems of all ages. The purpose of this study is to assess the impact of the lockdown on digital device usage, and consequently, the ocular surface health implications and circadian rhythm abnormalities related to digital eye strain. Methods: An open online survey was sent through various social media platforms and was open for a period of 2 weeks. Results: A total of 407 usable responses were obtained; the average age of respondents was 27.4 years. Typically, 93.6% of respondents reported an increase in their screen time since the lockdown was declared. The average increase in digital device usage was calculated at about 4.8 ± 2.8 h per day. The total usage per day was found to be 8.65 ± 3.74 hours. Sleep disturbances have been reported by 62.4% of people. Typically, 95.8% of respondents had experienced at least one symptom related to digital device usage, and 56.5% said that the frequency and intensity of these symptoms increased since the lockdown was declared. Conclusion: The study highlighted the drastic increase in use of digital devices after the initiation of the COVID-19 lockdown, and along with it, the slow deterioration of ocular health across all age groups. Awareness about prevention of digital eye strain should be stressed, and going forward, measures to bring these adverse effects to a minimum should be explored.


Asunto(s)
Astenopía/epidemiología , Betacoronavirus , Computadores , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Cuarentena/estadística & datos numéricos , Trastornos de la Visión/epidemiología , Adulto , Femenino , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Pandemias , Atención al Paciente , Encuestas y Cuestionarios , Adulto Joven
17.
Child Adolesc Ment Health ; 25(4): 267-269, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33025729

RESUMEN

The pandemic is creating unprecedented demand for mental health support for young people. While schools often facilitate mental health support for their students, the demands for online teaching and the uncertainty created by the pandemic make traditional delivery of support through schools challenging. Technology provides a potential way forward. We have developed a digital ecosystem, HABITS, that can be integrated into school and healthcare systems. This has allowed us to deploy specific evidence-based interventions directly, and through schools, to students and to parents in New Zealand during the current pandemic. Chatbot architecture is particularly suited to rapid iteration to provide specific information while apps can provide more generalised support. While technology can provide some solutions, it is important to be aware of the potential to increase current inequities, with those facing the greatest challenges to health and well-being, also least able to afford the resources to access digital interventions. Development of an integrated and equitable digital system will take time and collaboration.


Asunto(s)
Servicios de Salud del Niño/organización & administración , Infecciones por Coronavirus , Servicios de Salud Mental/organización & administración , Salud Mental , Pandemias , Neumonía Viral , Servicios de Salud Escolar/organización & administración , Estudiantes/psicología , Adolescente , Niño , Computadores , Ecosistema , Humanos , Nueva Zelanda , Telecomunicaciones
18.
Ann Biol Clin (Paris) ; 78(5): 519-526, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33026347

RESUMEN

Digital morphology hematology analyzers are becoming more prevalent in laboratories Aims: investigate practices and assess the benefits and limits of digital automated microscopy in hematology. METHODS: questionnaire sent by e-mail in 2018 to French public and private laboratories. RESULTS: out of 118 responses (56 private, 62 public), 117 participants had a CellaVision® microscope, 1 had a West Medica®. Practices were sometimes different, especially in the choice of smears to be digitized or for quality controls (16.1% had internal quality controls, 48.3% external quality controls); 62.1% never used the red blood cell (RBC) characterization tool; the number of cells counted varied from 100 to 400. The study reported a high rate of agreement for these benefits: traceability (95.7%), staff training (94.1%), eye strain (91.4%), risk of error (87.2%), time saving (83.6%). Among the disadvantages, apart from the inadequate search for platelets clumps (93.2%), the agreement rates were often lower: adaptation to digital images (61.2%), difficult assessment of atypical morphologies (49.6%) or RBC morphology (49.6%). CONCLUSION: despite well-established benefits, standardization of practices and technical improvement are still needed.


Asunto(s)
Automatización de Laboratorios , Pruebas Hematológicas/instrumentación , Hematología/instrumentación , Procesamiento de Imagen Asistido por Computador , Microscopía/instrumentación , Actitud del Personal de Salud , Automatización de Laboratorios/instrumentación , Automatización de Laboratorios/métodos , Automatización de Laboratorios/estadística & datos numéricos , Computadores , Pruebas Diagnósticas de Rutina/instrumentación , Pruebas Diagnósticas de Rutina/métodos , Pruebas Diagnósticas de Rutina/estadística & datos numéricos , Pruebas Diagnósticas de Rutina/tendencias , Francia/epidemiología , Pruebas Hematológicas/métodos , Pruebas Hematológicas/estadística & datos numéricos , Pruebas Hematológicas/tendencias , Hematología/métodos , Hematología/estadística & datos numéricos , Hematología/tendencias , Humanos , Procesamiento de Imagen Asistido por Computador/instrumentación , Procesamiento de Imagen Asistido por Computador/métodos , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Procesamiento de Imagen Asistido por Computador/tendencias , Satisfacción en el Trabajo , Microscopía/métodos , Microscopía/estadística & datos numéricos , Microscopía/tendencias , Práctica Profesional/estadística & datos numéricos , Práctica Profesional/tendencias , Control de Calidad , Encuestas y Cuestionarios
19.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3489-3492, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018755

RESUMEN

In this paper a new compression technique based on the discrete Tchebichef transform is presented. To comply with strict on-implant hardware implementation requirements, such as low power dissipation and small silicon area consumption, the discrete Tchebichef transform is modified and truncated. An algorithm is proposed to generate approximate transform matrices capable of truncation without suffering from destructive energy leakage among the coefficients. This is achieved by preserving orthogonality of the basis functions that convey majority portion of the signal energy. Based on the presented algorithm, a new truncated transformation matrix is proposed, which reduces the hardware complexity by up to 74% compared to that of the original transform. Hardware implementation of the proposed neural signal compression technique is prototyped using standard digital hardware. With pre-recorded neural signals as the input, compression rate of 26.15 is achieved while the root-mean-square of error is kept as low as 1.1%.Clinical Relevance- This paper proposes a technique for data compression in high-density neural recording brain implants, along with a power- and area-efficient hardware implementation. From among clinical applications of such implants one can point to neuro-prostheses, and brain-machine interfaces for therapeutic purposes.


Asunto(s)
Interfaces Cerebro-Computador , Compresión de Datos , Algoritmos , Computadores , Registros
20.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4046-4050, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018887

RESUMEN

In general, the signal chain in modern mobile Brain-Computer Interfaces (BCIs) is subdivided into at least two blocks. These are usually wirelessly connected with digital signal processing part implemented separately and often stationary. This causes a limited mobility and results in an additional, although avoidable, latency due to the wireless transmission channel. Therefore, a novel, entirely mobile FPGA-based platform for BCIs has been designed and implemented. While featuring highly efficient adaptability to targeted algorithms due to the ultra low power Flash-based FPGA, the stackable system design and the configurable hardware ensure flexibility for the use in different application scenarios. Powered through a single Li-ion battery, the miniaturized system area of half the size of a credit card leads to high mobility and thus allow for real-world scenario applicability. A Bluetooth Low Energy extension can be connected without any significant area cost, if a wireless data or control signal transmission channel is required. The resulting system is capable of acquiring and fully processing of up to 32 EEG channels with 24 bit precision each and a sampling rate of 250-16k samples per second with a total weight less than 60 g.


Asunto(s)
Interfaces Cerebro-Computador , Algoritmos , Computadores , Suministros de Energía Eléctrica , Procesamiento de Señales Asistido por Computador
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