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1.
Biosensors (Basel) ; 14(1)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38275305

RESUMO

This study examines the relationship between physiological complexity, as measured by Approximate Entropy (ApEn) and Sample Entropy (SampEn), and fitness levels in female athletes. Our focus is on their association with maximal oxygen consumption (VO2,max). Our findings reveal a complex relationship between entropy metrics and fitness levels, indicating that higher fitness typically, though not invariably, correlates with greater entropy in physiological time series data; however, this is not consistent for all individuals. For Heart Rate (HR), entropy measures suggest stable patterns across fitness categories, while pulse oximetry (SpO2) data shows greater variability. For instance, the medium fitness group displayed an ApEn(HR) = 0.57±0.13 with a coefficient of variation (CV) of 22.17 and ApEn(SpO2) = 0.96±0.49 with a CV of 46.08%, compared to the excellent fitness group with ApEn(HR) = 0.60±0.09 with a CV of 15.19% and ApEn(SpO2) =0.85±0.42 with a CV of 49.46%, suggesting broader physiological responses among more fit individuals. The larger standard deviations and CVs for SpO2 entropy may indicate the body's proficient oxygen utilization at higher levels of physical demand. Our findings advocate for combining entropy metrics with wearable sensor technology for improved biomedical analysis and personalized healthcare.


Assuntos
Oximetria , Oxigênio , Humanos , Feminino , Entropia , Exercício Físico
2.
Br J Anaesth ; 131(4): 640-644, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37544838

RESUMO

Recent concerns regarding the clinical accuracy of pulse oximetry in dark-skinned patients, specifically in detecting occult hypoxaemia, have motivated research on this topic and recently reported in this journal. We provide an overview of the technical aspects of the issue, the sources of inaccuracy, and the current regulations and limitations. These insights offer perspectives on how pulse oximetry can be improved to address these potential limitations.


Assuntos
Hipóxia , Oximetria , Humanos , Hipóxia/diagnóstico , Pacientes
3.
Materials (Basel) ; 16(6)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36984011

RESUMO

Amorphous microwires have attracted substantial attention in the past decade because of their useful technological applications. Their bistable magnetic response is determined by positive or negative magnetostriction, respectively. First-order reversal curves (FORC) are a powerful tool for analyzing the magnetization reversal processes of many-body ferromagnetic systems that are essential for a deeper understanding of those applications. After theoretical considerations about magnetostatic interactions among microwires, this work introduces a systematic experimental study and analysis of the FORC diagrams for magnetostrictive microwires exhibiting an individually bistable hysteresis loop, from a single microwire to sets of an increasing number of coupled microwires, the latter considered as an intermediate case to the standard many-body problem. We performed the study for sets of quasi-identical and different hysteretic microwires where we obtained the coercivity Hc and interaction Hu fields. In the cases with relevant magnetostatic interactions, FORC analysis supplies deeper information than standard hysteresis loops since the intrinsic fluctuations of the switching field generate a complex response. For sets of microwires with very different coercivity, the coercivity distributions of the individual microwires characterize the FORC diagram.

4.
Bioengineering (Basel) ; 10(2)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36829748

RESUMO

The market for wrist-worn devices is growing at previously unheard-of speeds. A consequence of their fast commercialization is a lack of adequate studies testing their accuracy on varied populations and pursuits. To provide an understanding of wearable sensors for sports medicine, the present study examined heart rate (HR) measurements of four popular wrist-worn devices, the (Fitbit Charge (FB), Apple Watch (AW), Tomtom runner Cardio (TT), and Samsung G2 (G2)), and compared them with gold standard measurements derived by continuous electrocardiogram examination (ECG). Eight athletes participated in a comparative study undergoing maximal stress testing on a cycle ergometer or a treadmill. We analyzed 1,286 simultaneous HR data pairs between the tested devices and the ECG. The four devices were reasonably accurate at the lowest activity level. However, at higher levels of exercise intensity the FB and G2 tended to underestimate HR values during intense physical effort, while the TT and AW devices were fairly reliable. Our results suggest that HR estimations should be considered cautiously at specific intensities. Indeed, an effective intervention is required to register accurate HR readings at high-intensity levels (above 150 bpm). It is important to consider that even though none of these devices are certified or sold as medical or safety devices, researchers must nonetheless evaluate wrist-worn wearable technology in order to fully understand how HR affects psychological and physical health, especially under conditions of more intense exercise.

5.
ACS Omega ; 7(39): 35153-35158, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36211079

RESUMO

Understanding the kinetics of electron transfer reactions involves active research in physics, chemistry, biology, and nano-tech. Here, we propose a model to apply in a broader framework by establishing a connection between thermodynamics and kinetics. From a purely thermodynamic point of view, electronic transfer Marcus' theory is revisited; consequently, calculations of thermodynamic variables such as mobility, energy, and entropy are provided. More significantly, two different regimes are explicitly established. In the anomalous region, an exergonic process associated with negative heat capacity appears. Further, in the same region, mobility, energy, and entropy decrease when the temperature increases.

6.
Sensors (Basel) ; 22(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35591092

RESUMO

Nowadays, pulse oximetry has become the standard in primary and intensive care units, especially as a triage tool during the current COVID-19 pandemic. Hence, a deeper understanding of the measurement errors that can affect precise readings is a key element in clinical decision-making. Several factors may influence the accuracy of pulse oximetry, such as skin color, body temperature, altitude, or patient movement. The skin pigmentation effect on pulse oximetry accuracy has long been studied reporting some contradictory conclusions. Recent studies have shown a positive bias in oxygen saturation measurements in patients with darkly pigmented skin, particularly under low saturation conditions. This review aims to study the literature that assesses the influence of skin pigmentation on the accuracy of these devices. We employed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement to conduct a systematic review retrospectively since February 2022 using WOS, PubMed, and Scopus databases. We found 99 unique references, of which only 41 satisfied the established inclusion criteria. A bibliometric and scientometrics approach was performed to examine the outcomes of an exhaustive survey of the thematic content and trending topics.


Assuntos
COVID-19 , Pigmentação da Pele , Bibliometria , Humanos , Oximetria , Oxigênio , Pandemias , Estudos Retrospectivos
7.
Biosensors (Basel) ; 11(10)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34677347

RESUMO

The myths surrounding women's participation in sport have been reflected in respiratory physiology. This study aims to demonstrate that continuous monitoring of blood oxygen saturation during a maximal exercise test in female athletes is highly correlated with the determination of the second ventilatory threshold (VT2) or anaerobic threshold (AnT). The measurements were performed using a pulse oximeter during a maximum effort test on a treadmill on a population of 27 healthy female athletes. A common behavior of the oxygen saturation evolution during the incremental exercise test characterized by a decrease in saturation before the aerobic threshold (AeT) followed by a second significant drop was observed. Decreases in peripheral oxygen saturation during physical exertion have been related to the athlete's physical fitness condition. However, this drop should not be a limiting factor in women's physical performance. We found statistically significant correlations between the maximum oxygen uptake and the appearance of the ventilatory thresholds (VT1 and VT2), the desaturation time, the total test time, and between the desaturation time and the VT2. We observed a relationship between the desaturation time and the VT2 appearance. Indeed, a linear regression model between the desaturation time and the VT2 appearance can predict 80% of the values in our sample. Besides, we suggest that pulse oximetry is a simple, fairly accurate, and non-invasive technique for studying the physical condition of athletes who perform physical exertion.


Assuntos
Oximetria , Consumo de Oxigênio , Saturação de Oxigênio , Atletas , Feminino , Humanos , Oxigênio
8.
J. health med. sci. (Print) ; 7(4): 215-221, oct.-dic. 2021.
Artigo em Espanhol | LILACS | ID: biblio-1396092

RESUMO

El objetivo del presente artículo ha sido describir el programa "Optimización de la Protección en Radiología Intervencionista Pediátrica en América Latina y el Caribe" (OPRIPALC) que nace el año 2018 como respuesta conjunta de la Organización Panamericana de la Salud y la Organización Mundial de la Salud, en cooperación con el Organismo Internacional de Energía Atómica, para colaborar con sus Estados miembros en asegurar que las exposiciones a la radiación de los pacientes pediátricos sean las mínimas necesarias durante los procedimientos intervencionistas. Actualmente, hay 18 centros de los siguientes 10 países que participan: Argentina, Brasil, Chile, Colombia, Costa Rica, Cuba, Ecuador, México, Perú y Uruguay. Para el desarrollo del programa se plantean una serie de objetivos, productos, actividades y resultados esperados. La puesta en marcha de la WEB de OPRIPALC ha significado un instrumento muy válido para seguir la información actualizada del programa. Un programa actualizado de formación en radioprotección para los profesionales implicados en el programa, se está realizando por medio de "webinars". Se deberá seguir actuando en la aplicación del programa de control de calidad básico para los equipos de rayos X participantes y validar los valores de los Niveles de Referencia para Diagnóstico (NRDs). Se propone formar un equipo de trabajo entre los Físicos Médicos y Tecnólogos Médicos participantes de OPRIPALC para implicarse en las pruebas de control básicas que todos los centros debieran realizar. Se han presentado algunos resultados iniciales de OPRIPALC en eventos científicos internacionales. Se está avanzando en proponer unos primeros valores sobre NRDs en procedimientos de intervencionismo cardiológico pediátrico por bandas de edad y peso. OPRIPALC es una de las pocas iniciativas de carácter regional para obtener valores de NRDs en procedimientos intervencionistas pediátricos. Se espera que tanto los valores de referencia como la metodología empleada en OPRIPALC, puedan ser utilizados en otras regiones del mundo.


The objective of this article has been to describe the program "Optimization of Protection in Pediatric Interventional Radiology in Latin America and the Caribbean" (OPRIPALC) that was born in 2018 as a joint response of the Pan American Health Organization and the World Organization of the Health, in cooperation with the International Atomic Energy Agency, to collaborate with its member states in ensuring that radiation exposures of pediatric patients are the minimum necessary during interventional procedures. Currently, there are 18 centers from the following 10 countries participating: Argentina, Brazil, Chile, Colombia, Costa Rica, Cuba, Ecuador, Mexico, Peru and Uruguay. For the development of the program, a series of objectives, products, activities and expected results are proposed. The launch of the OPRIPALC WEBSITE has been a very valid instrument for following up-to-date information on the program. An updated training program in radiation protection for the professionals involved in the program is being carried out through webinars. It should continue acting in the application of the basic quality control program for the participating X-ray equipment and validate the values of the Diagnostic Reference Levels (DRLs). It is proposed to form a work team among the OPRIPALC participating medical physicists to get involved in the basic control tests that all centers should carry out. Some initial results of OPRIPALC have been presented at international scientific events. Progress is being made in proposing first values on DRLs in pediatric cardiac intervention procedures by age and weight bands. OPRIPALC is one of the few regional initiatives to obtain DRLs values in pediatric interventional procedures. It is expected that both the reference values and the methodology used in OPRIPALC can be used in other regions of the world.


Assuntos
Humanos , Criança , Pediatria/normas , Proteção Radiológica/normas , Cardiologia/normas , Controle de Qualidade , Padrões de Referência , Valores de Referência , Segurança , Radiologia Intervencionista , Região do Caribe , Técnicas de Diagnóstico Cardiovascular , Otimização de Processos , Níveis de Referência de Diagnóstico , América Latina
9.
Med. leg. Costa Rica ; 21(2): 71-84, sept. 2004.
Artigo em Espanhol | LILACS | ID: lil-401251

RESUMO

La violencia contra las mujeres es un problema antiguo, tanto como la sociedad, pero hasta hace sólo tres décadas permaneció oculto tras mecanismos culturales que ayudados por la prensa que le llamaban "Sucesos". Esta manera, se le negó su carácter de problema social y se le redujo a un asunto privado que viven las mujeres. Hacer visible esta realidad oculta, requirió años de trabajo, hubo que acuñar términos para señarlar las diferentes manifestaciones de la violencia oculta: violencia física, violencia psicológica, violencia sexual, violencia patrimonial, incesto, acoso sexual, femicidio, revictimización. Términos que además de inexistentes eran impensables, como la violación en el matrimonio. Sin embargo esta realidad se hizo pesadilla, la violencia contra las mujeres, que en los 90 comenzaba a ser visibilizada por las organizaciones feministas, una década después es ya materia de trabajo de las instituciones pero al mismo tiempo, estos instrumentos de análisis han sido reciclados a favor de las relaciones dominantes de los hombres y de las instituciones contra las mujeres y las usuarias. Las etiquetas profesionales como el "síndrome de invalidez aprendida", lo que ha hecho es confundir a las autoridades al asignarle el valor de una "nueva incapacidad de las mujeres", revictimizando de nuevo al no comprender que el problema no es intrapsíquico sino social. Los profesionales pueden ayudar a que se entienda que la que esta invalida es la sociedad y sus estructuras de poder y no la capacidad psíquica de la mujer que lucha por sus derechos. Palabras clave: Violencia oculta, mujeres, violencia física, violencia psicológica, violencia sexual, violencia patrimonial, incesto, acoso sexual, femicidio, revictimización, intrasíquico


Assuntos
Humanos , Feminino , Mulheres Maltratadas , Escalas de Graduação Psiquiátrica , Psicologia , Assédio Sexual , Comportamento Social , Violência , Costa Rica
10.
Med. leg. Costa Rica ; 19(2): 63-77, sept. 2002. ilus
Artigo em Espanhol | LILACS | ID: lil-325313

RESUMO

Si bien la interrupción voluntaria del embarazo es una práctica común en todo el mundo, el tema es sumamente controversial ya que en él se conjugan aspectos fundamentales como el inicio de la vida humana, el derecho de las mujeres a controlar su propio cuerpo, la sexualidad, la naturaleza de las responsabilidades del Estado para interferir en este terreno y las tensiones entre las visiones seculares y religiosas sobre la vida. El debate permite precisamente visibilizar el hecho de que sobre estos temas no existen visiones homogéneas e inmutables. En ese sentido, a pesar de que en muchos países existen leyes que penalizan el aborto, el asunto nos remite al terreno de principios morales y éticos contrapuestos. Aquí se discuten algunas de las implicaciones de estas controversias y se brinda información sobre la incidencia del aborto, así como sobre las consecuencias tanto del aborto inseguro como la despenalización. Finalmente, se analizan las implicaciones de la penalización del aborto para el cumplimiento de algunos derechos fundamentales como el respeto a las diferencias, la libre elección, la autodeterminación y la tolerancia. Palabras claves: Aborto, aborto inducido, derecho de las mujeres, aborto inseguro, despenalización, tolerancia.


Assuntos
Aborto Induzido , Bioética , Ética , Legislação , Legislação Médica , Mulheres , Saúde da Mulher , Costa Rica
11.
Med. leg. Costa Rica ; 19(1): 5-16, mar. 2002. ilus
Artigo em Espanhol | LILACS | ID: lil-359453

RESUMO

Para muchas mujeres y niñas la familia es el grupo social más violento y el hogar más peligroso. Si se compara los soldados americanos muertos en la guerra de Vietnan 57685, contra más de 70000 mujeres asesinadas en los hogares de Vietnan en el mismo periodo se comprende la magnitud de lo que estamos hablando. En Costa Rica, país de paz, de las mujeres que han acudido a pedir ayuda a CEFEMINA, 15 por ciento han sido atacadas con armas de fuego, 31 por ciento con arma blanca, 24 por ciento con otros objetos. El riesgo de muerte es parte de la vivencia cotidiana de muchas mujeres, 58 por ciento han sentido peligro de morir en manos de su agresor, 47 por ciento han pensado suicidarse, 48 por ciento ha tenido que dejar su hogar por miedo de morir. En el presente estudio se detectan 44 homicidios de mujeres (Femicidio), que no aparecen en los anuarios del Organismo de Investigación Judicial, haciendo del subregistro de agresiones otra forma de hacer violencia contra las mujeres. Palabras claves: violencia contra mujeres y niñas, homicidio, femicidio, problema social, violencia familiar, CEFEMINA, violencia cotidiana, pornografía, explotación sexual.


Assuntos
Humanos , Feminino , Mulheres Maltratadas , Violência Doméstica , Família , Saúde da Família , Relações Familiares , Homicídio , Maus-Tratos Conjugais , Violência , Mulheres , Saúde da Mulher , Costa Rica
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