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1.
Pediatr Exerc Sci ; : 1-10, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39168460

RESUMEN

PURPOSE: This systematic review and meta-analysis aimed to systematically examine and summarize recent evidence on the effects of soccer-based training (SBT) on anthropometric measures in children and adolescents with overweight/obesity. METHODS: Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis 2020 guidelines, a thorough literature search across 7 electronic databases was conducted on October 11, 2023. The studies' methodological quality was evaluated using the QualSyst tool, followed by conducting a meta-analysis with a random-effects model, and the certainty of evidence was assessed. RESULTS: Six studies were included, with 4 studies of strong methodological quality and 2 studies of moderate methodological quality. The results of the meta-analysis revealed SBT decreases fat mass percentage (effect size [ES] = 0.47 [small]; P = .002), with no significant effect of SBT on body mass index (ES = 0.180 [small]; P = .275), body mass (ES = 0.183 [trivial]; P = .212), fat-free mass (ES = 0.074 [trivial]; P = .635), or waist circumference (ES = 0.358 [small]; P = .053). The certainty of evidence was moderate for all outcomes. CONCLUSIONS: SBT appears to decrease fat mass percentage, without affecting body mass, body mass index, fat-free mass, or waist circumference in obese/overweight children and adolescents. These findings require further investigation given the moderate certainty of evidence. REGISTRATION: The protocol of this review was registered in the Open Science Framework database (https://doi.org/10.17605/OSF.IO/8P4V2).

2.
PLoS One ; 19(7): e0305060, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39012850

RESUMEN

In addressing issues related to electromagnetic interference, the demand for ferrite materials with exceptional magnetic and dielectric properties has escalated recently. In this research, sol-gel auto combustion technique prepared Nickel zinc ferrites substituted with cerium, denoted as Ni0.5Zn0.5Ce0.02Fe1.98O4.X-ray diffraction (XRD), Vibrating Sample Magnetometer (VSM), and Field Emissions Scanning Electron Microscope (FESEM) were used to investigate the structure, magnetic properties, and morphology of Cerium doped NiZn Nano ferrites, respectively. The magnetic and dielectric properties of the sample was examined within a frequency range of 2.5-5.5 GHz. Sample exhibits low permittivity (2.2), high permeability (1.4), low dielectric (0.35) and magnetic loss tangent (-0.5) and highest saturation magnetization measuring 30.28 emu/g. A Novel Double-band, 4x4 MIMO window grill-modeled antennas operating on 3.5 GHz and 4.8 GHz frequency bands for 5G smartphones is designed using the CST microwave studio suite. The performance of window grilled 4x4 MIMO antenna model with Cerium doped NiZn nano ferrites as substrate, is investigated and found the return loss of -35 and -32 dB, with the bandwidth of 200MHz, gain (1.89 & 4.38dBi), envelope correlation coefficient (0.00185), channel capacity loss (0.2bps/Hz), and interterminal isolation of (22& 19dB).The results show that the antenna size is reduced with improved bandwidth, higher isolation and better diversity gain performance using Cerium doped NiZn nano ferrite substrate compared to conventional dielectric substrates.


Asunto(s)
Cerio , Compuestos Férricos , Níquel , Zinc , Cerio/química , Compuestos Férricos/química , Níquel/química , Zinc/química , Difracción de Rayos X , Microondas
3.
Cureus ; 16(6): e63107, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39070339

RESUMEN

Infective endocarditis (IE) is a serious cardiovascular condition with the potential to lead to severe valvular regurgitation. We present a case of a 65-year-old male who presented with a fever and was diagnosed with IE through point-of-care ultrasound (POCUS). The patient's condition subsequently led to severe aortic regurgitation. Timely diagnosis facilitated by POCUS played a crucial role in the management of this case. The patient underwent successful timely surgical intervention to prevent further infective embolism and heart failure due to severe acute aortic regurgitation. This case underscores the pivotal role of POCUS in the early diagnosis and multidisciplinary management of cardiology diseases, highlighting its importance in delivering optimal patient care.

4.
Cureus ; 16(7): e65468, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39071073

RESUMEN

This review aims to identify the associated attributes of willingness to pay (WTP) for overweight and obesity interventions. A narrative review was conducted by partially adopting the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. A non-exhaustive search using a pre-defined strategy and keywords was done on three selected literature databases: Pubmed, Scopus, and Web of Science. The inclusion criteria for the review were original studies written in English, published between 2000 and 2022, and focused on WTP for overweight and obesity interventions in adults. The extracted studies were manually screened for their eligibility through three cascading tiers: the title, the abstract, and the full article. Only nine original studies were eligible for review based on the screening procedure of 40 screened articles. There was heterogeneity in the study designs, methods, target populations, study duration, and perspectives across the studies. The majority of the studies showed that higher WTP was associated with younger age, having higher income, being female, having higher body mass index (BMI), having the perception of being overweight, habits, and attitudes. WTP is also attributed to the associated percentage of weight loss, long-term health risk reduction, time to noticeable weight loss, delivery mode, side effects, lifestyle modification, and costs of interventions. The identification of common attributes of the WTP for overweight and obesity intervention can assist in the formulation and implementation of effective evidence-based policies. Specific sub-groups with low WTP could be targeted via unique initiatives to improve their participation in weight-loss interventions.

5.
SLAS Technol ; : 100164, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39033878

RESUMEN

In the face of an aging population, smart healthcare services are now within reach, thanks to the proliferation of high-speed internet and other forms of digital technology. Data problems in smart healthcare, unfortunately, put artificial intelligence in this area to serious limitations. There are several issues, including a lack of standard samples, noisy data interference, and actual data that is missing. A three-stage AI-based data generating strategy is suggested to handle missing datasets, using a small sample dataset obtained from a smart healthcare program community in a specific city: Step one involves generating the dataset's basic attributes using a tree-based generation strategy that takes the original data distribution into account. Step two involves using the Naive Bayes algorithm to create basic indicators of behavioural capability assessment for the samples. Step three builds on stage two and uses a multivariate linear regression method to create evaluation criteria and indicators of high-level behavioural capability. Six problems involving multiple classifications and two tasks using multiple labels are implemented using various neural network-based training strategies on the obtained data to assess the usefulness of the dataset for downstream tasks. To ensure that the data collected is genuine and useful, the experimental data must be analysed and expert knowledge must be included.

6.
J Sports Med Phys Fitness ; 64(7): 631-639, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38916086

RESUMEN

BACKGROUND: During a prolonged quarantine, there is a need to monitor aerobic fitness levels of trained individuals who are isolated with a simple fitness test that can be performed in confined space of their own homes. This study examined the reliability, validity, usefulness and sensitivity of a novel 3-min submaximal heart rate burpees test (or SubHR3-MBT) to assess and monitor changes in aerobic fitness, of trained athletes. In the SubHR3-MBT, male and female athletes performed 48 and 39 burpees respectively, within 3 min by following a constant beeping pace. The performance criterion of the SubHR3-MBT is the highest heart rate attained (or exercise HRpeak) at the end of 3-min (wherein a lower exercise HRpeak indicates a higher level of aerobic fitness). METHODS: A total of 40 male and female national athletes from various sports volunteered for the study. RESULTS: For reliability (Part 1), the SubHR3-MBT showed good relative and excellent reliability, with intraclass correlation coefficient 0.90 and coefficient of variation 2.6%, respectively. For validity (Part II), there was significant negative correlation between relative exercise HRpeak with respiratory gas-measured VO2max (r=-0.51, large; P<0.001). The test's technical error of measurement of 2.3 is slightly greater than its smallest worthwhile change of 1.5. For sensitivity (Part III), the athletes were tested twice for their SubHR3-MBT and VO2max, once at baseline and another at a followed-up test after >10 weeks. There was a significant correlation between the % change in relative exercise HRpeak with the % change in VO2max (r=-0.66, large; P<0.001). CONCLUSIONS: The SubHR3-MBT is a reliable, valid, marginally useful test and may be able to track changes in aerobic fitness in trained athletes with moderate levels of sensitivity, in case of future isolation due to pandemic occurrence.


Asunto(s)
Prueba de Esfuerzo , Frecuencia Cardíaca , Humanos , Masculino , Femenino , Reproducibilidad de los Resultados , Prueba de Esfuerzo/métodos , Frecuencia Cardíaca/fisiología , Adulto , Aptitud Física/fisiología , Atletas , Adulto Joven , Sensibilidad y Especificidad , COVID-19
8.
Sci Rep ; 14(1): 12326, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811630

RESUMEN

Within concrete engineering, the uptake of self-compacting concrete (SCC) represents a notable trend, delivering improved workability and placement efficiency. However, challenges persist, notably in achieving optimal performance while mitigating environmental impacts, particularly in cement consumption. However, simply reducing the cement content in the mix design can directly compromise the structural-concrete requirements. Towards these challenges, global trends emphasize the utilization of appropriate waste materials in blended concrete. This study explored a promising strategy by integrating supplementary cementitious materials (SCMs) to contribute to the United Nations' Sustainable Development Goals (SDGs) in addition to the engineering contributions. It suggests an optimal combination of Metakaolin (MK) and Limestone Powder (LP) to partially substitute cement. The research methodology employs the response surface method (RSM) to systematically explore the ideal ingredient ratios. Through a comprehensive analysis of orthogonal array of 16 mixes, encompassing both mixture and process variables, this study aims to explain the effects of MK and LP addition on the rheological and mechanical properties of SCC with varying cement replacement levels. In terms of mixture constituents, the total composition of cement, MK, and LP was fixed at 100%, while coarse aggregate (CA), fine aggregate (FA), and the water-to-binder ratio were held as process variables. In order to assess the rheological properties of the mix-design, various tests including slump flow, L-box, and sieve segregation were conducted. Additionally, to evaluate mechanical strength, samples were tested for compressive strength at both 7 and 28 days. Findings from the experiments reveal higher concentrations of MK result in reduced workability and hardened properties. Through RSM-based designed experimentation covering both rheological and mechanical aspects, it is observed that the optimal cement replacement level lies between 40 and 55%. The findings of this study contribute to the advancement of sustainable and structurally robust concrete practices, offering insights into the optimal utilization of SCMs to meet both engineering requirements and environmental sustainability goals.

9.
J Sports Sci ; 42(7): 646-654, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38771259

RESUMEN

We aimed to examine the effects of Ramadan fasting (RF) and high-intensity short-term maximal performance on elite soccer players' shooting accuracy, executive function (EF), and perceptions. Sixteen Muslim elite players fasting during Ramadan underwent assessments before (BR), during (DR), and after Ramadan (AR). Soccer-specific technical performance was evaluated using the Loughborough Soccer Shooting Test (LSST) before and after a 5-metre shuttle run test (5mSRT), conducted at the same time-of-day (17:00 h). Performance metrics recorded included higher distance (HD), total distance (TD), and fatigue index (FI). RPE after a 5-min warm-up and each repetition of the 5mSRT were obtained, and the mean RPE score was calculated. Trail Making Test (TMT Parts A and B) were used after the warm-up and the 5mSRT. Perceived difficulty (PD) was assessed following the LSST. HD, TD, and FI were not affected by RF (p > 0.05). DR, RPE and accuracy scores in the LSST were significantly lower after the 5mSRT compared to BR (1.29 vs. 1.24 AU; 1.29 vs. 1.24, respectively). In conclusion, RF had no adverse effects on physical performance. However, when combined with high-intensity running sessions, RF may impact accuracy and PD, and these adverse effects seem to have been translated into EF.


Asunto(s)
Rendimiento Atlético , Cognición , Ayuno , Islamismo , Percepción , Fútbol , Humanos , Fútbol/fisiología , Fútbol/psicología , Ayuno/fisiología , Rendimiento Atlético/fisiología , Rendimiento Atlético/psicología , Adulto Joven , Cognición/fisiología , Masculino , Percepción/fisiología , Función Ejecutiva/fisiología , Adulto , Fatiga , Esfuerzo Físico/fisiología
10.
Chem Asian J ; 19(16): e202400220, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-38654594

RESUMEN

The advancement of a sustainable and scalable catalyst for hydrogen production is crucial for the future of the hydrogen economy. Electrochemical water splitting stands out as a promising pathway for sustainable hydrogen production. However, the development of Pt-free electrocatalysts that match the energy efficiency of Pt while remaining economical poses a significant challenge. This review addresses this challenge by highlighting latest breakthroughs in Pt-free catalysts for the hydrogen evolution reaction (HER). Specifically, we delve into the catalytic performance of various transition metal phosphides, metal carbides, metal sulphides, and metal nitrides toward HER. Our discussion emphasizes strategies for enhancing catalytic performance and explores the relationship between structural composition and the performance of different electrocatalysts. Through this comprehensive review, we aim to provide insights into the ongoing efforts to overcome barriers to scalable hydrogen production and pave the way for a sustainable hydrogen economy.

11.
J Neurosci Methods ; 406: 110128, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38554787

RESUMEN

BACKGROUND: In recent times, the expeditious expansion of Brain-Computer Interface (BCI) technology in neuroscience, which relies on electroencephalogram (EEG) signals associated with motor imagery, has yielded outcomes that rival conventional approaches, notably due to the triumph of deep learning. Nevertheless, the task of developing and training a comprehensive network to extract the underlying characteristics of motor imagining EEG data continues to pose challenges. NEW METHOD: This paper presents a multi-scale spatiotemporal self-attention (SA) network model that relies on an attention mechanism. This model aims to classify motor imagination EEG signals into four classes (left hand, right hand, foot, tongue/rest) by considering the temporal and spatial properties of EEG. It is employed to autonomously allocate greater weights to channels linked to motor activity and lesser weights to channels not related to movement, thus choosing the most suitable channels. Neuron utilises parallel multi-scale Temporal Convolutional Network (TCN) layers to extract feature information in the temporal domain at various scales, effectively eliminating temporal domain noise. RESULTS: The suggested model achieves accuracies of 79.26%, 85.90%, and 96.96% on the BCI competition datasets IV-2a, IV-2b, and HGD, respectively. COMPARISON WITH EXISTING METHODS: In terms of single-subject classification accuracy, this strategy demonstrates superior performance compared to existing methods. CONCLUSION: The results indicate that the proposed strategy exhibits favourable performance, resilience, and transfer learning capabilities.


Asunto(s)
Interfaces Cerebro-Computador , Electroencefalografía , Imaginación , Humanos , Electroencefalografía/métodos , Imaginación/fisiología , Atención/fisiología , Redes Neurales de la Computación , Actividad Motora/fisiología , Encéfalo/fisiología , Movimiento/fisiología , Procesamiento de Señales Asistido por Computador
12.
Heliyon ; 10(4): e25712, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38375251

RESUMEN

In this paper, a multi-input multi-output (MIMO) antenna for future mobile phone applications operating in sub-6 GHza using a novel combination of an E-shaped slot placed on the ground plane and an F-shaped probe is used to achieve a dual-band independently tunable antenna. The proposed antenna is not only self-isolated but it has also effectively achieved high isolation of greater than 17 dB in both 3.5 GHz (3.4 - 3.6 GHz) and 4.7 GHz (4.6 - 4.87 GHz) frequency bands for 8-element MIMO antenna configuration for 5G smartphones. The simple yet compact size of (0.035 λ0Image 1 0.23 λ0), of the slot antenna produces a balanced slot mode which not only reduces the ground effects but also improves the isolation between two adjacent input ports. The novelty of the proposed dual-band MIMO antenna is its independent control of each band across a wide frequency band and results demonstrate higher efficiency (64% - 71%) and diversity gain performance in both frequency bands. Furthermore, the antenna is designed by the meticulous configurations of 8-antenna elements without employing any external decoupling structure to attain the desired polarization diversity. The prototype of this 8-element MIMO antenna is also fabricated and measured to validate its simulated performance. The simple structure of the proposed design and high efficiency makes it a promising candidate for 5G smartphones.

13.
J Clin Neurophysiol ; 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38376923

RESUMEN

INTRODUCTION: This study examines the usability and comfort of a behind-the-ear seizure detection device called brain seizure detection (BrainSD) that captures ictal electroencephalogram (EEG) data using four scalp electrodes. METHODS: This is a feasibility study. Thirty-two patients admitted to a level 4 Epilepsy Monitoring Unit were enrolled. The subjects wore BrainSD and the standard 21-channel video-EEG simultaneously. Epileptologists analyzed the EEG signals collected by BrainSD and validated it using video-EEG data to confirm its accuracy. A poststudy survey was completed by each participant to evaluate the comfort and usability of the device. In addition, a focus group of UT Southwestern epileptologists was held to discuss the features they would like to see in a home EEG-based seizure detection device such as BrainSD. RESULTS: In total, BrainSD captured 11 of the 14 seizures that occurred while the device was being worn. All 11 seizures captured on BrainSD had focal onset, with three becoming bilateral tonic-clonic and one seizure being of subclinical status. The device was worn for an average of 41 hours. The poststudy survey showed that most users found the device comfortable, easy-to-use, and stated they would be interested in using BrainSD. Epileptologists in the focus group expressed a similar interest in BrainSD. CONCLUSIONS: Brain seizure detection is able to detect EEG signals using four behind-the-ear electrodes. Its comfort, ease-of-use, and ability to detect numerous types of seizures make BrainSD an acceptable at-home EEG detection device from both the patient and provider perspective.

14.
Eur J Appl Physiol ; 124(6): 1861-1874, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38233706

RESUMEN

BACKGROUND: This study examined the effects of a single all-out bout of 30-s sprint-cycle performed daily for 5 consecutive days per week for 6 weeks, on aerobic fitness, muscle strength and metabolic-health markers in physically active young males and females. METHODS: Healthy, physically active 20-28 year olds, were randomly assigned to either experimental (EXP, N = 11) or non-training control (CON, N = 8) group. With supervision, the EXP group performed one bout of 30-s sprint-cycle daily, Mondays to Fridays over 6 weeks, while CON group continued with their usual lifestyle. The followings were measured at pre- and post-intervention: maximal aerobic power, peak torque of knee extensors and flexors at velocities 30° s-1 and 300° s-1, resting heart rate, resting blood pressure, body fat percentage, fasting lipid profile, fasting blood glucose, and fasting insulin levels. RESULTS: There were no significant improvements in the EXP group for all the measured variables (all P > 0.05); except for significant interaction effects in peak torque of knee extensors at 30° s-1 (P = 0.044) and low-density lipoprotein-cholesterol (P = 0.046). Post hoc test indicate that CON group showed decline in their low-density lipo-proteins levels (P = 0.024). CONCLUSION: Six weeks of one all-out bout of 30-s sprint-cycle per day, for 5 consecutive days per week, was ineffective in improving cardiovascular fitness, maximal strength, and most health markers in physically active young adults. The present results when combined with the previous literature suggest that there is a possibility of a minimum threshold for a number of sprint-cycle bouts needed to be performed before any form of cardio-metabolic-health benefit is accrued.


Asunto(s)
Fuerza Muscular , Humanos , Masculino , Femenino , Adulto , Fuerza Muscular/fisiología , Adulto Joven , Capacidad Cardiovascular/fisiología , Ejercicio Físico/fisiología , Aptitud Física/fisiología , Biomarcadores/sangre , Frecuencia Cardíaca/fisiología , Presión Sanguínea/fisiología
18.
Br J Sports Med ; 58(3): 136-143, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-37923379

RESUMEN

OBJECTIVE: To systematically review, summarise and appraise findings of published systematic reviews, with/without meta-analyses, examining associations between Ramadan fasting observance (RO), health-related indices and exercise test performances in athletes and physically active individuals. DESIGN: Overview of systematic reviews with assessment of reviews' methodological quality. DATA SOURCES: PubMed, Web of Science, Scopus, Cochrane Database of Systematic Reviews, SPORTDiscus, ProQuest, PsycINFO and SciELO. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Systematic reviews with/without meta-analyses examining associations of RO with health-related indices and exercise performances in athletes and physically active individuals. RESULTS: Fourteen systematic reviews (seven with meta-analyses) of observational studies, with low-to-critically-low methodological quality, were included. Two reviews found associations between RO and decreased sleep duration in athletes and physically active individuals. One review suggested athletes may experience more pronounced reductions in sleep duration than physically active individuals. One review found associations between RO and impaired sleep quality in athletes and physically active individuals. RO was associated with decreased energy, carbohydrate and water intake in adult-aged athletes, but not adolescents. One review suggests RO was associated with athletes' increased feelings of fatigue and decreased vigour. No association was found between RO and athletes' lean mass or haematological indices. RO was unfavourably associated with changes in athletes' performance during high-intensity exercise testing. CONCLUSION: Continuance of training during RO could be associated with athletes' mood state disturbances, decreased sleep duration and performance decline during high-intensity exercise testing, while preserving lean mass. However, careful interpretation is necessary due to the low-to-critically-low methodological quality of the included reviews.


Asunto(s)
Rendimiento Atlético , Prueba de Esfuerzo , Humanos , Anciano , Ayuno Intermitente , Revisiones Sistemáticas como Asunto , Ejercicio Físico , Atletas
19.
Chem Rec ; 24(1): e202300358, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38150653

RESUMEN

Energy conversion, consumption, and storage technologies are essential for a sustainable energy ecosystem. Energy storage technologies like batteries, supercapacitors, and fuel cells bridge the gap between energy conversion and consumption, ensuring a reliable energy supply. From ancient methods to modern advancements, research has focused on improving energy storage devices. Challenges remain, including performance, environmental impact and cost, but ongoing research aims to overcome these limitations. A special issue titled "Recent Advances in Electrochemical Energy Storage" presents cutting-edge progress and inspiring further development in energy storage technologies.

20.
PLoS One ; 18(12): e0288593, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38113223

RESUMEN

In this paper, a 12x12 dual-band MIMO antenna for 5G smartphones is proposed. It operates in the sub 6 GHz (2.4GHz and 3.5GHz) frequency bands. The MIMO antenna elements are printed on an FR4 epoxy substrate that has a thickness of 0.8mm. The main substrate measures 150 × 75 × 0.8 mm3, while the side substrates have dimensions of 75 × 6 × 0.8mm3. The twelve dual-band antenna elements are compact in size. Each antenna element size is reduced significantly, which is 11.20 × 5.98 mm2(0.0896λ × 0.04784λ). These antenna elments are arranged in such a way that the MIMO antenna not only provides polarization diversity but also helps in achieving good performance in terms of isolation, which is more than 13.5 dB between two adjacent antenna elements. Another significance of the proposed antenna is that both the frequency bands can be tuned independently by varying the corresponding length of each arm. The performance parameters like efficiency is around 40-56% for the lower band and it is 48-62% for the upper band. The envelope correlation coefficient (ECC) is below 0.04 in both frequency bands for the proposed dual band MIMO antenna.


Asunto(s)
Resinas Epoxi , Teléfono Inteligente , Refracción Ocular
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