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1.
Heliyon ; 10(5): e26355, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38434340

ABSTRACT

This work analyzes hemodynamic phenomena within the aorta of two elderly patients and their impact on blood flow behavior, particularly affected by an endovascular prosthesis in one of them (Patient II). Computational Fluid Dynamics (CFD) was utilized for this study, involving measurements of velocity, pressure, and wall shear stress (WSS) at various time points during the third cardiac cycle, at specific positions within two cross sections of the thoracic aorta. The first cross-section (Cross-Section 1, CS1) is located before the initial fluid bifurcation, just before the right subclavian artery. The second cross-section (Cross-Section 2, CS2) is situated immediately after the left subclavian artery. The results reveal that, under regular aortic geometries, velocity and pressure magnitudes follow the principles of fluid dynamics, displaying variations. However, in Patient II, an endoprosthesis near the CS2 and the proximal border of the endoprosthesis significantly disrupts fluid behavior owing to the pulsatile flow. The cross-sectional areas of Patient I are smaller than those of Patient II, leading to higher flow magnitudes. Although in CS1 of Patient I, there is considerable variability in velocity magnitudes, they exhibit a more uniform and predictable transition. In contrast, CS2 of Patient II, where magnitude variation is also high, displays irregular fluid behavior due to the endoprosthesis presence. This cross-section coincides with the border of the fluid bifurcation. Additionally, the irregular geometry caused by endovascular aneurysm repair contributes to flow disruption as the endoprosthesis adjusts to the endothelium, reshaping itself to conform with the vessel wall. In this context, significant alterations in velocity values, pressure differentials fluctuating by up to 10%, and low wall shear stress indicate the pronounced influence of the endovascular prosthesis on blood flow behavior. These flow disturbances, when compounded by the heart rate, can potentially lead to changes in vascular anatomy and displacement, resulting in a disruption of the prosthesis-endothelium continuity and thereby causing clinical complications in the patient.

2.
J Otol ; 2023 May 19.
Article in English | MEDLINE | ID: mdl-37362607

ABSTRACT

Objective: To describe audiological symptoms, audiometric profile, and distortion product otoacoustic emission in symptomatic patients recovering from SARS-CoV-2 infection (positive RT-PCR test) and asymptomatic patients (negative RT-PCR test). Methods: An analytical cross-sectional study was conducted using data obtained from clinical charts, physical examination, audiometry, and distortion product otoacoustic emission on 40 patients [case patients (CP)] recovering from SARS-CoV-2 infection diagnosed by a positive RT-PCR test and 22 asymptomatic participants with a negative RT-PCR test [non-case (NC)]. Results: Sixty-two patients (mean age: 31.1 and 28.2 years in the CP and NC groups, respectively) were included. All participants were young without significant comorbidities, risk factors for hearing loss or otological history. Vertigo (5%), tinnitus (17.5%) and aural fullness/hearing loss (35%) were found in the CP group. A statistically significant difference was found in specific frequencies (1000, 4000, and 8000 Hz) and pure tone average (low and high conversational frequencies with increased threshold in the PC group compared with the NC group), which was not found in distortion product otoacoustic emission. Conclusion: Audiovestibular symptoms are frequent in symptomatic patients recovering from SARS-CoV-2 infection. SARS-CoV-2 infection was consistently associated with an increased audiometric hearing threshold at specific frequencies and low tone average.

3.
Sensors (Basel) ; 20(6)2020 Mar 22.
Article in English | MEDLINE | ID: mdl-32235783

ABSTRACT

Through the application of intelligent systems in driver assistance systems, the experience of traveling by road has become much more comfortable and safe. In this sense, this paper then reports the development of an intelligent driving assistant, based on vehicle telemetry and road accident risk map analysis, whose responsibility is to alert the driver in order to avoid risky situations that may cause traffic accidents. In performance evaluations using real cars in a real environment, the on-board intelligent assistant reproduced real-time audio-visual alerts according to information obtained from both telemetry and road accident risk map analysis. As a result, an intelligent assistance agent based on fuzzy reasoning was obtained, which supported the driver correctly in real-time according to the telemetry data, the vehicle environment and the principles of secure driving practices and transportation regulation laws. Experimental results and conclusions emphasizing the advantages of the proposed intelligent driving assistant in the improvement of the driving task are presented.


Subject(s)
Automobile Driving , Telemetry/methods , Accidents, Traffic , Automobiles , Humans , Risk Assessment , Risk Factors , Safety
4.
Sensors (Basel) ; 20(1)2019 Dec 19.
Article in English | MEDLINE | ID: mdl-31861639

ABSTRACT

In this work, authors address workload computation combining human activity recognition and heart rate measurements to establish a scalable framework for health at work and fitness-related applications. The proposed architecture consists of two wearable sensors: one for motion, and another for heart rate. The system employs machine learning algorithms to determine the activity performed by a user, and takes a concept from ergonomics, the Frimat's score, to compute the corresponding physical workload from measured heart rate values providing in addition a qualitative description of the workload. A random forest activity classifier is trained and validated with data from nine subjects, achieving an accuracy of 97.5%. Then, tests with 20 subjects show the reliability of the activity classifier, which keeps an accuracy up to 92% during real-time testing. Additionally, a single-subject twenty-day physical workload tracking case study evinces the system capabilities to detect body adaptation to a custom exercise routine. The proposed system enables remote and multi-user workload monitoring, which facilitates the job for experts in ergonomics and workplace health.


Subject(s)
Accelerometry/methods , Human Activities , Wearable Electronic Devices , Accelerometry/instrumentation , Adult , Exercise , Humans , Machine Learning , Male , Micro-Electrical-Mechanical Systems
5.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1016642

ABSTRACT

Objetivo.Evaluar los tipos de perfil facial blando mediante los ángulos de convexidad facial (ACF) y convexidad facial total (ACFT) y su relación con la posición distal de los segundos molares primarios en niños entre 3 y 5 años. Métodos. Estudio transversal en 28 niños chilenos con al menos un apellido de origen español y dentición primaria completa, quienes cumplían con los requisitos del estudio. Para evaluar el ACF y ACFT se tomó fotografía digital estandarizada del perfil lateral. Con la prueba exacta de Fisher se comparó los perfiles blandos según edad y género, y con t de Student para muestra única se evaluó los promedios angulares. Resultados. Para el ACF la media fue 167,1° ± 5,1, y para ACFT 145,8° ± 3,7. Se observó convexidad alta del ACF en 21,4% de los niños, media en 60,7% y baja en 17,9%; y para el ACFT en 17,9%, 67,9% y 14,2% res-pectivamente. El promedio del ACF para la relación molar escalón mesial, plano vertical y escalón distal fue de 169,2° ± 3.7, 168° ± 4,9 y 162,5°±4,8, mientras que para ACFT fue 146,7° ± 4,4, 146,3° ± 3,6 y 143,5° ± 2,8 respectivamente. Conclusiones. Se observó para ACF relación significativa entre la presencia de perfil convexo alto y escalón distal, además de diferencia significativa entre el promedio de este ángulo en escalón distal en comparación al promedio de referencia. El ACF puede ser indicador aceptable de escalón distal, sin embargo, no es certero al evaluar un plano vertical o escalón mesial. Palabras clave: Cefalometría; Preescolar; Fotografía; Dentición (fuente: DeCS Bireme).


Objetive. To observe the types of soft facial profile according to the angles of facial convexity (FCA) and total facial convexity (TFCA), in addition to evaluating their rela-tionship with the distal position of the primary second molars in children between 3 and 5 years. Methods. Twenty-eight out of 200 children with complete primary dentition were examined to determine the distal relation of primary second molars, and a digital photographic examination of their lateral profile was performed to evaluate the ACF and ACFT. With the Fisher's exact test, soft tissue profiles were compared according to age and gender, and with Student t test for a single sample, the angular averages were evaluated. Results. The mean of the FCA was 167.1 ° ± 5.1, and the TFCA was 145.8 ° ± 3.7. A high convexity of the FCA was observed in 21.4% of the children, medium in 60.7% and low in 17.9%. While in the TFCA it was divided into 17.9% with high convexity, 67.9% medium and 14.2% low. The average value of the FCA for the mesial step, flush terminal and distal step 169.2 ° ± 3.7, 168 ° ± 4.9 and 162.5 ° ± 4.8, while the average of the TFCA was 146.7 ° ± 4.4, 146.3 ° ± 3.6 and 143.5 ° ± 2.8 respectively. Conclusions. A significant relationship between the presence of a high convex profile and a distal step molar relationship was observed for the FCA, as well as a significant difference between the average of this angle in distal step compared to the reference average. Keywords: Cephalometry; Child preschool; Photography; Tooth Deciduous (source: MeSH NLM).

6.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1016649

ABSTRACT

Objetivo.El presente estudio tuvo como objetivo analizar la prevalencia de las anomalías dentomaxilares en niños de 3 a 10 años que solicitaron atención en la Facultad de Odon-tología de la Universidad de Chile en el año 2018. Métodos. Se realizó un estudio des-criptivo y de tipo transversal, donde el universo correspondió a los pacientes atendidos en la UTE (Unidad de Trabajo del Estudiante) Clínica del niño y adolescente de 4to año de la Facultad de Odontología de la Universidad de Chile. Cohorte 2018. Para la evaluación de anomalías dentomaxilares se consideró la Clasificación Biogenética de Bonn Modificada. Anomalías intermaxilares. Resultados. Del total de la muestra analizada (n: 106), el 45,1% de los pacientes presentaron alteraciones de tipo transversal, vertical y/o sagital. Conclusiones. La anomalía transversal más prevalente fue la mordida cruzada unilateral. La anomalía vertical más prevalente fue la sobremordida. Las anomalías sagitales más prevalente fueron las distoclusiones y la mordida invertida simple. Palabras clave: Niño; Maloclusión; Ortodoncia (fuente: DeCS BIREME).


Objetive. The present study aimed to analyze the prevalence of dentomaxillary anomalies in children aged 3 to 10 years old who requested attention at the Faculty of Dentistry of the University of Chile in the year 2018. Methods. A descriptive and cross-sectional study was carried out, where the universe corresponded to the patients attended in the SWU (Student Work Unit) of the Child and Adolescent Clinic of the 4th year of the Faculty of Dentistry of the University of Chile. Cohort 2018. For the evaluation of dentomaxillary anomalies, the Modified Bonn Biogenetic Classification was considered. Intermaxillary abnormalities. Results. Of the total sample analyzed (n: 106), 45.1% of the patients presented transverse, vertical and/or sagittal type alterations. Conclusions. The most prevalent transversal anomaly was the unilateral cross bite. The most prevalent vertical anomaly was the deep bite. The most prevalent sagittal anomalies were the distoclusions and the simple Inverted bite. Keywords: Child; Malocclusion; Orthodontics (Source: MeSH NLM).

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