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1.
Hum Brain Mapp ; 43(4): 1295-1308, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34796574

RESUMEN

High-density electroencephalography (HD-EEG) is currently limited to laboratory environments since state-of-the-art electrode caps require skilled staff and extensive preparation. We propose and evaluate a 256-channel cap with dry multipin electrodes for HD-EEG. We describe the designs of the dry electrodes made from polyurethane and coated with Ag/AgCl. We compare in a study with 30 volunteers the novel dry HD-EEG cap to a conventional gel-based cap for electrode-skin impedances, resting state EEG, and visual evoked potentials (VEP). We perform wearing tests with eight electrodes mimicking cap applications on real human and artificial skin. Average impedances below 900 kΩ for 252 out of 256 dry electrodes enables recording with state-of-the-art EEG amplifiers. For the dry EEG cap, we obtained a channel reliability of 84% and a reduction of the preparation time of 69%. After exclusion of an average of 16% (dry) and 3% (gel-based) bad channels, resting state EEG, alpha activity, and pattern reversal VEP can be recorded with less than 5% significant differences in all compared signal characteristics metrics. Volunteers reported wearing comfort of 3.6 ± 1.5 and 4.0 ± 1.8 for the dry and 2.5 ± 1.0 and 3.0 ± 1.1 for the gel-based cap prior and after the EEG recordings, respectively (scale 1-10). Wearing tests indicated that up to 3,200 applications are possible for the dry electrodes. The 256-channel HD-EEG dry electrode cap overcomes the principal limitations of HD-EEG regarding preparation complexity and allows rapid application by not medically trained persons, enabling new use cases for HD-EEG.


Asunto(s)
Corteza Cerebral/fisiología , Electrodos , Electroencefalografía/instrumentación , Potenciales Evocados Visuales/fisiología , Adulto , Impedancia Eléctrica , Electroencefalografía/métodos , Electromiografía , Humanos , Monitoreo Ambulatorio , Dispositivos Electrónicos Vestibles
2.
Sensors (Basel) ; 22(20)2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36298430

RESUMEN

Dry electrodes for electroencephalography (EEG) allow new fields of application, including telemedicine, mobile EEG, emergency EEG, and long-term repetitive measurements for research, neurofeedback, or brain-computer interfaces. Different dry electrode technologies have been proposed and validated in comparison to conventional gel-based electrodes. Most previous studies have been performed at a single center and by single operators. We conducted a multi-center and multi-operator study validating multipin dry electrodes to study the reproducibility and generalizability of their performance in different environments and for different operators. Moreover, we aimed to study the interrelation of operator experience, preparation time, and wearing comfort on the EEG signal quality. EEG acquisitions using dry and gel-based EEG caps were carried out in 6 different countries with 115 volunteers, recording electrode-skin impedances, resting state EEG and evoked activity. The dry cap showed average channel reliability of 81% but higher average impedances than the gel-based cap. However, the dry EEG caps required 62% less preparation time. No statistical differences were observed between the gel-based and dry EEG signal characteristics in all signal metrics. We conclude that the performance of the dry multipin electrodes is highly reproducible, whereas the primary influences on channel reliability and signal quality are operator skill and experience.


Asunto(s)
Interfaces Cerebro-Computador , Electroencefalografía , Humanos , Reproducibilidad de los Resultados , Electrodos , Impedancia Eléctrica
3.
An Acad Bras Cienc ; 91(2): e20190018, 2019 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-31241710

RESUMEN

Tissue engineering holds as a prominent technique to repair or replace the damaged human parts to recreate its native function. In this research, a novel scaffold based on polyurethane (PU) comprising megni oil was electrospun for tissue engineering applications. The obtained polyurethane blended with megni oil nanofibers were characterized by scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), contact angle measurement and atomic force microscopy (AFM). Furthermore, the blood compatibility of the fabricated nanocomposites evaluated through activated prothrombin time (APTT), partial thromboplastin time (PT) and hemolysis assay to determine the anticoagulant nature. The morphological results showed that the fabricated nanocomposites showed reduced fiber size (789 ± 143.106 nm) than the pristine control (890 ± 116.91 nm). The interaction between PU and megni oil was identified by the hydrogen bond formation evident in the FTIR. The incorporation of megni oil in the PU decreased the wettability behavior (113.3° ± 1.528) and improved the surface roughness (646 nm). Preliminary evaluation of blood compatibility assessments was carried out using APTT, PT and hemolysis assay revealed the enhanced antithrombogenicity nature of the fabricated nanocomposites than the PU. Hence, we conclude that the fabricated new nanocomposite membrane with desirable characteristics which might find potential application in the tissue engineering applications.


Asunto(s)
Materiales Biocompatibles/química , Nanocompuestos/química , Aceites/química , Poliuretanos/química , Ingeniería de Tejidos/métodos , Ensayo de Materiales , Espectroscopía Infrarroja por Transformada de Fourier
4.
J Phys Ther Sci ; 30(7): 933-937, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30034101

RESUMEN

[Purpose] This study examined how incremental cardiorespiratory exercise may affect the speech rate and Counting Talk Test (CTT)-estimated exercise intensity. [Participants and Methods] Twenty-four healthy adults performed the CTT while exercising on a treadmill at 6 stages of incremental exercise ranging from 40% to 85% of heart rate reserve (HRR). Each participant started walking on the treadmill at 3 to 4 km/h and 0% elevation to warm up. The increments of treadmill grades were adjusted until targeted heart rates corresponding to the percentages of HRR were reached. Then, the participants were asked to rate their perceived exertion while the treadmill grades were maintained for 2-minutes bouts of each exercise stage. At the last minute of the exercise stage, the CTT was performed within a single breath. [Results] The speech rates in the CTT appeared to vary significantly during exercise. Moreover, the CTT-estimated exercise intensity showed significant reductions at several exercise stages. [Conclusion] The CTT estimates exercise intensity semi-quantitatively throughout incremental exercise. However, moderate and vigorous intensities could not be significantly delineated by the current CTT method. This could be due to the variability in speech rates that were indicated as the exercise progressed.

5.
J Med Syst ; 41(10): 148, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28812247

RESUMEN

This paper proposes a robotic Transesophageal Echocardiography (TOE) system concept for Catheterization Laboratories. Cardiovascular disease causes one third of all global mortality. TOE is utilized to assess cardiovascular structures and monitor cardiac function during diagnostic procedures and catheter-based structural interventions. However, the operation of TOE underlies various conditions that may cause a negative impact on performance, the health of the cardiac sonographer and patient safety. These factors have been conflated and evince the potential of robot-assisted TOE. Hence, a careful integration of clinical experience and Systems Engineering methods was used to develop a concept and physical model for TOE manipulation. The motion of different actuators of the fabricated motorized system has been tested. It is concluded that the developed medical system, counteracting conflated disadvantages, represents a progressive approach for cardiac healthcare.


Asunto(s)
Ecocardiografía Transesofágica , Cateterismo , Humanos , Monitoreo Fisiológico , Robótica
6.
Can J Respir Ther ; 52(1): 17-26, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26909010

RESUMEN

BACKGROUND: Evidence regarding the effectiveness of incentive spirometry (ISy) on postoperative pulmonary outcomes after thoracic, cardiac and abdominal surgery remains inconclusive. This is attributed to various methodological issues inherent in ISy trials. Patient compliance has also been highlighted as a possible confounding factor; however, the status of evidence regarding patient compliance in these trials is unknown. OBJECTIVE: To explore the status of evidence on patient compliance with ISy interventions in randomized controlled trials (RCTs) in the above contexts. METHOD: A systematic search using MEDLINE, EMBASE and CINAHL databases was conducted to obtain relevant RCTs from 1972 to 2015 using the inclusion criteria. These were examined for specific ISy parameters, methods used for determining compliance and reporting on compliance. Main outcome measures were comparison of ISy parameters prescribed and assessed, and reporting on compliance. RESULTS: Thirty-six relevant RCTs were obtained. Six ISy parameters were identified in ISy prescriptions from these trials. Almost all (97.2%) of the trials had ISy prescriptions with specific parameters. Wilcoxon signed-rank test revealed that the ISy parameters assessed were significantly lower (Z=-5.433; P<0.001) than those prescribed; 66.7% of the trials indicated use of various methods to assess these parameters. Only six (16.7%) trials included reports on compliance; however, these were also incomprehensive. CONCLUSIONS: There is a scarcity and inconsistency of evidence regarding ISy compliance. Compliance data should be obtained using reliable and standardized methods to facilitate comparisons between and among trials. These should be reported comprehensively to facilitate valid inferences regarding ISy intervention effectiveness.


HISTORIQUE: Les données relatives à l'efficacité de la spirométrie incitative (ISy) sur la capacité pulmonaire après une chirurgie cardiaque, thoracique ou abdominale ne sont pas concluantes. Ce phénomène est attribuable à divers problèmes méthodologiques inhérents aux essais d'ISy. La compliance des patients peut également constituer un facteur confusionnel. Toutefois, on ne connaît pas l'état des données sur la compliance des patients lors de ces essais. OBJECTIF: Explorer l'état des données sur la compliance des patients aux interventions d'ISy dans le cadre d'essais aléatoires et contrôlés (EAC) réalisés dans les contextes susmentionnés. MÉTHODOLOGIE: À l'aide des critères d'inclusion, les chercheurs ont fouillé systématiquement les bases de données MEDLINE, EMBASE et CINAHL pour obtenir les EAC de 1972 à 2015. Ils ont analysé certains paramètres d'ISy, les méthodes utilisées pour déterminer la compliance et les rapports de compliance. Les principales mesures de résultats étaient la comparaison des paramètres d'ISy prescrits et évalués et les rapports de compliance. RÉSULTATS: Les chercheurs ont extrait 36 EAC pertinents. Ils en ont tiré six paramètres dans les prescriptions d'ISy. Presque tous les essais (97,2 %) comportaient des prescriptions d'ISy aux paramètres précis. Le test de la somme des rangs de Wilcoxon a révélé que les paramètres d'ISy évalués étaient considérablement plus faibles (Z= −5,433; P<0,001) que ceux prescrits, et 66,7 % des essais indiquaient l'utilisation de diverses méthodes pour évaluer ces paramètres. Seulement six essais (16,7 %) comportaient des rapports de compliance, également incomplets. CONCLUSIONS: Les données sur la compliance à l'ISy sont rares et contradictoires. Il faudrait obtenir les données de compliance au moyen de méthodes fiables et standardisées afin de faciliter les comparaisons entre les essais. Les rapports devraient être détaillés pour favoriser des inférences valides sur l'efficacité des interventions d'ISy.

7.
J Biomed Inform ; 55: 174-87, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25900270

RESUMEN

This work investigates, whether openEHR with its reference model, archetypes and templates is suitable for the digital representation of demographic as well as clinical data. Moreover, it elaborates openEHR as a tool for modelling Hospital Information Systems on a regional level based on a national logical infrastructure. OpenEHR is a dual model approach developed for the modelling of Hospital Information Systems enabling semantic interoperability. A holistic solution to this represents the use of dual model based Electronic Healthcare Record systems. Modelling data in the field of obstetrics is a challenge, since different regions demand locally specific information for the process of treatment. Smaller health units in developing countries like Brazil or Malaysia, which until recently handled automatable processes like the storage of sensitive patient data in paper form, start organizational reconstruction processes. This archetype proof-of-concept investigation has tried out some elements of the openEHR methodology in cooperation with a health unit in Colombo, Brazil. Two legal forms provided by the Brazilian Ministry of Health have been analyzed and classified into demographic and clinical data. LinkEHR-Ed editor was used to read, edit and create archetypes. Results show that 33 clinical and demographic concepts, which are necessary to cover data demanded by the Unified National Health System, were identified. Out of the concepts 61% were reused and 39% modified to cover domain requirements. The detailed process of reuse, modification and creation of archetypes is shown. We conclude that, although a major part of demographic and clinical patient data were already represented by existing archetypes, a significant part required major modifications. In this study openEHR proved to be a highly suitable tool in the modelling of complex health data. In combination with LinkEHR-Ed software it offers user-friendly and highly applicable tools, although the complexity built by the vast specifications requires expert networks to define generally excepted clinical models. Finally, this project has pointed out main benefits enclosing high coverage of obstetrics data on the Clinical Knowledge Manager, simple modelling, and wide network and support using openEHR. Moreover, barriers described are enclosing the allocation of clinical content to respective archetypes, as well as stagnant adaption of changes on the Clinical Knowledge Manager leading to redundant efforts in data contribution that need to be addressed in future works.


Asunto(s)
Registros Electrónicos de Salud/organización & administración , Almacenamiento y Recuperación de la Información/métodos , Obstetricia/organización & administración , Programas Informáticos , Interfaz Usuario-Computador , Vocabulario Controlado , Europa (Continente) , Femenino , Humanos , Registro Médico Coordinado/métodos , Modelos Organizacionales , Modelación Específica para el Paciente , Lenguajes de Programación , Semántica
8.
Sci Technol Adv Mater ; 16(3): 033504, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27877785

RESUMEN

Cardiovascular disease claims millions of lives every year throughout the world. Biomaterials are used widely for the treatment of this fatal disease. With the advent of nanotechnology, the use of nanocomposites has become almost inevitable in the field of biomaterials. The versatile properties of nanocomposites, such as improved durability and biocompatibility, make them an ideal choice for various biomedical applications. Among the various nanocomposites, polyhedral oligomeric silsesquioxane-poly(carbonate-urea)urethane, bacterial cellulose with polyvinyl alcohol, carbon nanotubes, graphene oxide and nano-hydroxyapatite nanocomposites have gained popularity as putative choices for biomaterials in cardiovascular applications owing to their superior properties. In this review, various studies performed utilizing these nanocomposites for improving the mechanical strength, anti-calcification potential and hemocompatibility of heart valves are reviewed and summarized. The primary motive of this work is to shed light on the emerging nanocomposites for heart valve applications. Furthermore, we aim to promote the prospects of these nanocomposites in the campaign against cardiovascular diseases.

9.
ScientificWorldJournal ; 2014: 912051, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25506620

RESUMEN

People affected with leukemia are on the rise and several strategies were employed to thwart this deadly disease. Recent decade of research focuses on phenolic constituents as a tool for combating various inflammatory, cancer, and cardiac diseases. Our research showed honey and its phenolic constituents as crusaders against cancer. In this work, we explored the antileukemic activity of selected honey and one of its phenolic constituent eugenol against L1210 leukemia animal model. Results of this experiment showed that the selected honey samples as well as eugenol after intraperitoneal injection could not increase the median survival time (MST) of animals. Further, there was only slight marginal increase in the %T/C values of honey and eugenol treated groups. The number of phenolics present in the honey may not be a prime factor to promote antileukemic effect since there was no difference in the MST of two different honeys tested. This study limits the use of selected honey and eugenol against leukemia animal model.


Asunto(s)
Eugenol/uso terapéutico , Leucemia Linfoide/tratamiento farmacológico , Fenoles/uso terapéutico , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Eugenol/farmacología , Miel , Leucemia Linfoide/patología , Masculino , Ratones Endogámicos DBA , Fenoles/farmacología
10.
STAR Protoc ; 5(2): 103115, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38861381

RESUMEN

Manufacturing techniques play an essential role in obtaining optimum mechanical properties of composites. Vacuum-assisted resin infusion (VARI) is a composite fabrication approach for optimal fiber volume fraction. Here, we present a protocol for manufacturing glass fiber-reinforced polymer (GFRP) samples by applying VARI to a modified complex Arcan fixture. We describe steps for material preparation, molding preparation, setting vacuum system, resin mixing, and degassing. We then detail procedures for vacuum infusion process and cutting composites for shear testing samples. For complete details on the use and execution of this protocol, please refer to Alandro et al.1.


Asunto(s)
Vidrio , Vacio , Vidrio/química , Ensayo de Materiales , Polímeros/química
11.
Data Brief ; 53: 110139, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38357454

RESUMEN

This paper presents a dataset of load-displacement obtained from shear loading tests on pure GFRP laminates and hybrid GFRP-graphite filler laminates. The specimens were cut according to the ASTM D 7078 standard, and the width and thickness of the notch area were measured at least three times. Shear loading was applied at a rate of 2 mm/min, and data were recorded from unloading until specimen failure. The data provides information on the maximum load and unique behavior of GFRP laminates. Based on the obtained load, the shear stress (MPa) unit can be calculated. This data can serve as a basis for researchers and engineers working with GFRP laminates and hybrid GFRP-graphite filler laminates.

12.
BMC Res Notes ; 16(1): 194, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37667339

RESUMEN

OBJECTIVE: Genetic polymorphisms in ACE and ACE2 genes are involved in the RAS regulation of blood pressure and their activity may confer susceptibility to hypertension. In addition, they may play a role in SARS-CoV-2 pathogenesis and the severity of COVID-19. This study aims to determine the effect of genetic variations in the ACE (rs4331) and ACE2 (rs2074192) genes with hypertension comorbidity on the severity of COVID-19 in the Indonesian population. RESULT: 186 patients were enrolled and assigned into the COVID-19 group (n = 95) and non-COVID-19 group (n = 91) in this cross-sectional study. GG genotype frequency was dominant in ACE gene, but there were no significant differences between the groups (p = 0.163). The two groups had a significant difference (p = 0.000) for the CC genotype frequency (0,37 vs. 0.01) in the ACE2 gene. The proportion of women with COVID-19 is higher (51%), but men with hypertension had more severe symptoms (44%). Men with hypertension comorbidity, GG (ACE), and TT (ACE2) genotypes tended to have moderate-to-severe symptoms (25%). Similarly, women with hypertension as well as GG and CT genotypes tended to have moderate-to-severe symptoms (21%). We conclude that hypertension and mutations in the ACE (rs4331) and ACE2 (rs2074192) genes affect the severity of COVID-19.


Asunto(s)
Enzima Convertidora de Angiotensina 2 , COVID-19 , Hipertensión , Peptidil-Dipeptidasa A , Femenino , Humanos , Masculino , Enzima Convertidora de Angiotensina 2/genética , COVID-19/epidemiología , COVID-19/genética , Estudios Transversales , Genotipo , Hipertensión/genética , Peptidil-Dipeptidasa A/genética
13.
Artículo en Inglés | MEDLINE | ID: mdl-38083598

RESUMEN

Physiological direct current (DC) potential shifts in electroencephalography (EEG) can be masked by artifacts such as slow electrode drifts. To reduce the influence of these artifacts, linear detrending has been proposed as a pre-processing step. We considered quadratic detrending, which has hardly been addressed for ultralow frequency components in EEG. We compared the performance of linear and quadratic detrending in simultaneously acquired DC-EEG and transcutaneous partial pressure of carbon dioxide during two activation methods: hyperventilation (HV) and apnea (AP). Quadratic detrending performed significantly better than linear detrending in HV, while for AP, our analysis was inconclusive with no statistical significance. We conclude that quadratic detrending should be considered for DC-EEG preprocessing.


Asunto(s)
Artefactos , Electroencefalografía , Dióxido de Carbono , Electrodos , Presión Parcial
14.
An Acad Bras Cienc ; 84(4): 1157-68, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23207710

RESUMEN

Current two-dimensional (2D) ultrasonic marker measurements are inherent with intra- and inter-observer variability limitations. The objective of this paper is to investigate the performance of conventional 2D ultrasonic marker measurements and proposed programmable interactive three-dimensional (3D) marker evaluation. This is essentially important to analyze that the measurement on 3D volumetric measurement possesses higher impact and reproducibility vis-à-vis 2D measurement. Twenty three cases of prenatal ultrasound examination were obtained from collaborating hospital after Ethical Committee's approval. The measured 2D ultrasonic marker is Nuchal Translucency or commonly abbreviated as NT. Descriptive analysis of both 2D and 3D ultrasound measurement were calculated. Three trial measurements were taken for each method. Both data were tested with One-Sample Kolmogorov-Smirnov Test and results indicate that markers measurements were distributed normally with significant parametric values at 0.621 and 0.596 respectively. Computed mean and standard deviation for both measurement methods are 1.4495 ± 0.46490 (2D) and 1.3561 ± 0.50994 (3D). ANOVA test shows that computerized 3D measurements were found to be insignificantly different from the mean of conventional 2D at the significance level of 0.05. With Pearson's correlation coefficient value or R = 0.861, the result proves strong positive linear correlation between 2D and 3D ultrasonic measurements. Reproducibility and accuracy of 3D ultrasound in NT measurement was significantly increased compared with 2D B-mode ultrasound prenatal assessment. 3D reconstructed imaging has higher clinical values compare to 2D ultrasound images with less diagnostics information.


Asunto(s)
Medida de Translucencia Nucal/métodos , Trisomía/diagnóstico , Algoritmos , Análisis de Varianza , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagenología Tridimensional , Variaciones Dependientes del Observador , Embarazo , Reproducibilidad de los Resultados
15.
Molecules ; 17(6): 6290-304, 2012 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-22634840

RESUMEN

Phenolic phytochemicals are a broad class of nutraceuticals found in plants which have been extensively researched by scientists for their health-promoting potential. One such a compound which has been comprehensively used is eugenol (4-allyl-2-methoxyphenol), which is the active component of Syzigium aromaticum (cloves). Aromatic plants like nutmeg, basil, cinnamon and bay leaves also contain eugenol. Eugenol has a wide range of applications like perfumeries, flavorings, essential oils and in medicine as a local antiseptic and anesthetic. Increasing volumes of literature showed eugenol possesses antioxidant, antimutagenic, antigenotoxic, anti-inflammatory and anticancer properties. Molecular mechanism of eugenol-induced apoptosis in melanoma, skin tumors, osteosarcoma, leukemia, gastric and mast cells has been well documented. This review article will highlight the antiproliferative activity and molecular mechanism of the eugenol induced apoptosis against the cancer cells and animal models.


Asunto(s)
Anticarcinógenos/farmacología , Apoptosis/efectos de los fármacos , Eugenol/farmacología , Neoplasias/metabolismo , Animales , Anticarcinógenos/química , Anticarcinógenos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Eugenol/química , Eugenol/uso terapéutico , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/prevención & control
17.
Front Physiol ; 13: 832647, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35422713

RESUMEN

Purpose: When utilizing breathing for speech, the rate and volume of inhalation, as well as the rate of exhalation during the utterance, seem to be largely governed by the speech-controlling system and its requirements with respect to phrasing, loudness, and articulation. However, since the Talk Test represents a non-standardized form of assessment of exercise intensity estimation, this study aimed to compare the utterance rate and the estimated exercise intensity using a newly introduced time-controlled monosyllabic Talk Test (tMTT) versus a self-paced Counting Talk Test (CTT) across incremental exercise stages and examined their associations with the exercise physiological measures. Methods: Twenty-four participants, 10 males and 14 females (25 ± 4.0 yr; 160 ± 10 cm; 62 ± 14.5 kg) performed two sessions of submaximal cardiorespiratory exercise at incremental heart rate reserve (HRR) stages ranging from 40 to 85% of HRR: one session was performed with a currently available CTT that was affixed to a wall in front of the participants, and the other session was conducted with a tMTT with a 1-s inter-stimulus interval that was displayed from a tablet. In each session, the participants performed six stages of exercise at 40, 50, 60, 70, 80, and 85% HRR on a treadmill and were also asked to rate their perceived exertion based on Borg's 6 to 20 Rating of Perceived Exertion (RPE) at each exercise stage. Results: The newly designed tMTT significantly delineated all the six stages of incremental exercise (p ≤ 0.017), while CTT could only delineate exercise stages at 60, 80, and 85% HRR. However, in estimations of exercise intensity, the tMTT demonstrated only moderate associations with HRR and Borg's RPE, similarly to the CTT. Conclusion: If the purpose of exercise monitoring is to detect the intensity of light, moderate, and vigorous exercise intensity, the tMTT could be more universally applicable. However, due to its larger variability of speech rate across exercise intensities, the time-regulated approach may alter the speech breathing characteristics of the exercising individuals in other ways that should be investigated in future research.

18.
Front Digit Health ; 3: 723204, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34778867

RESUMEN

The study of carbon dioxide expiration is called capnometry. The graphical representation of capnometry is called capnography. There is a growing interest in the usage of capnography as the usage has expanded toward the study of metabolism, circulation, lung perfusion and diffusion, quality of spontaneous respiration, and patency of airways outside of its typical usage in the anesthetic and emergency medicine field. The parameters of the capnograph could be classified as carbon dioxide (CO2) concentration and time points and coordinates, slopes angle, volumetric studies, and functional transformation of wave data. Up to date, there is no gold standard device for the calculation of the capnographic parameters. Capnography digitization using the image processing technique could serve as an option. From the algorithm we developed, eight identical breath waves were tested by four investigators. The values of the parameters chosen showed no significant difference between investigators. Although there were no significant differences between any of the parameters tested, there were a few related parameters that were not calculable. Further testing after refinement of the algorithm could be done. As more capnographic parameters are being derived and rediscovered by clinicians and researchers alike for both lung and non-lung-related diseases, there is a dire need for data analysis and interpretation. Although the proposed algorithm still needs minor refinements and further large-scale testing, we proposed that the digitization of the capnograph via image processing technique could serve as an intellectual option as it is fast, convenient, easy to use, and efficient.

19.
Med Biol Eng Comput ; 59(2): 431-447, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33495984

RESUMEN

Wearable electronics and sensors are increasingly popular for personal health monitoring, including smart shirts containing electrocardiography (ECG) electrodes. Optimal electrode performance requires careful selection of the electrode position. On top of the electrophysiological aspects, practical aspects must be considered due to the dynamic recording environment. We propose a new method to obtain optimal electrode placement by considering multiple dimensions. The electrophysiological aspects were represented by P-, R-, and T-peak of ECG waveform, while the shirt-skin gap, shirt movement, and regional sweat rate represented the practical aspects. This study employed a secondary data set and simulations for the electrophysiological and practical aspects, respectively. Typically, there is no ideal solution that maximizes satisfaction degrees of multiple electrophysiological and practical aspects simultaneously; a compromise is the most appropriate approach. Instead of combining both aspects-which are independent of each other-into a single-objective optimization, we used multi-objective optimization to obtain a Pareto set, which contains predominant solutions. These solutions may facilitate the decision-makers to decide the preferred electrode locations based on application-specific criteria. Our proposed approach may aid manufacturers in making decisions regarding the placement of electrodes within smart shirts.


Asunto(s)
Electrocardiografía , Movimiento , Electrodos
20.
Sci Rep ; 11(1): 14534, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34267247

RESUMEN

We propose a novel automatic segmentation algorithm that separates the components of human skin cells from the rest of the tissue in fluorescence data of three-dimensional scans using non-invasive multiphoton tomography. The algorithm encompasses a multi-stage merging on preprocessed superpixel images to ensure independence from a single empirical global threshold. This leads to a high robustness of the segmentation considering the depth-dependent data characteristics, which include variable contrasts and cell sizes. The subsequent classification of cell cytoplasm and nuclei are based on a cell model described by a set of four features. Two novel features, a relationship between outer cell and inner nucleus (OCIN) and a stability index, were derived. The OCIN feature describes the topology of the model, while the stability index indicates segment quality in the multi-stage merging process. These two new features, combined with the local gradient magnitude and compactness, are used for the model-based fuzzy evaluation of the cell segments. We exemplify our approach on an image stack with 200 × 200 × 100  µm3, including the skin layers of the stratum spinosum and the stratum basale of a healthy volunteer. Our image processing pipeline contributes to the fully automated classification of human skin cells in multiphoton data and provides a basis for the detection of skin cancer using non-invasive optical biopsy.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Piel/diagnóstico por imagen , Tomografía Óptica/métodos , Algoritmos , Humanos , Microscopía de Fluorescencia por Excitación Multifotónica/métodos
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