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1.
Front Psychol ; 15: 1365310, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38725957

RESUMEN

Aim: This research sought to identify the association between sports participation and resilience in children and adolescents as a means to enhance mental health. Methods: A comprehensive survey was carried out, encompassing primary, middle, and high school students from chosen educational institutions. The analytical sample comprised 67,281 students of school age. Sports participation and resilience were evaluated using validated assessment tools, while relevant covariates, such as sex and school grade, were assessed through self-reported questionnaires. Generalized Linear Models were applied to ascertain the association between sports participation and resilience for the entire sample, and separately for subgroups divided by gender or school grade, after controlling for covariates. Results: Among the 67,281 school students, males constituted 51.9% of the sample. Approximately 47.1% of the entire sample reported no sports participation, and the average resilience score was 24.7. The regression model analysis revealed that, in the entire sample, increased in sports participation was linked to higher resilience scores (odds ratio [OR] for 1-3 times per month: 1.20, 95%CI: 1.16-1.24; OR for 1-2 times per week: 1.38, 95%CI: 1.33-1.43; OR for 3 times or more per week: 1.72, 95%CI: 1.65-1.79). Analyses stratified by gender and school grade indicated that sports participation was consistently associated with greater resilience. Conclusion: This study provides cross-sectional evidence supporting the positive association between sports participation and the resilience of children and adolescents, underscoring the potential of encouraging sports participation as a strategy for promoting mental health resilience. The findings presented herein should be subject to further confirmation or refutation in future research endeavors.

2.
Nanomicro Lett ; 16(1): 196, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753068

RESUMEN

Phase change materials (PCMs) offer a promising solution to address the challenges posed by intermittency and fluctuations in solar thermal utilization. However, for organic solid-liquid PCMs, issues such as leakage, low thermal conductivity, lack of efficient solar-thermal media, and flammability have constrained their broad applications. Herein, we present an innovative class of versatile composite phase change materials (CPCMs) developed through a facile and environmentally friendly synthesis approach, leveraging the inherent anisotropy and unidirectional porosity of wood aerogel (nanowood) to support polyethylene glycol (PEG). The wood modification process involves the incorporation of phytic acid (PA) and MXene hybrid structure through an evaporation-induced assembly method, which could impart non-leaking PEG filling while concurrently facilitating thermal conduction, light absorption, and flame-retardant. Consequently, the as-prepared wood-based CPCMs showcase enhanced thermal conductivity (0.82 W m-1 K-1, about 4.6 times than PEG) as well as high latent heat of 135.5 kJ kg-1 (91.5% encapsulation) with thermal durability and stability throughout at least 200 heating and cooling cycles, featuring dramatic solar-thermal conversion efficiency up to 98.58%. In addition, with the synergistic effect of phytic acid and MXene, the flame-retardant performance of the CPCMs has been significantly enhanced, showing a self-extinguishing behavior. Moreover, the excellent electromagnetic shielding of 44.45 dB was endowed to the CPCMs, relieving contemporary health hazards associated with electromagnetic waves. Overall, we capitalize on the exquisite wood cell structure with unidirectional transport inherent in the development of multifunctional CPCMs, showcasing the operational principle through a proof-of-concept prototype system.

3.
ACS Omega ; 9(12): 14249-14254, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38559994

RESUMEN

In vitro diagnostics (IVDs) based on electrochemical immunosensors are crucial for disease screening, diagnosis, prognosis, and treatment monitoring. However, label-free electrochemical immunosensors commonly suffer from poor specificity, leading to false positives. To address this issue, we propose a highly sensitive and precise electrochemical immunosensor for protein marker detection. This approach involves directly labeling the detection antibodies (Ab2) with thionine (Thi). The Ab2 labeled by Thi exhibits a distinct redox peak upon targeted voltage stimulation, enabling accurate quantification of protein biomarkers. Thi-modified antibodies provide significant advantages over traditional antibody modification methods, such as enhanced detection sensitivity, improved accuracy, and specificity in protein marker identification. The method is straightforward and efficient, ensuring specific analyte detection while minimizing interference from other substances in the sample. Additionally, a multielectrode detection method was employed, achieving remarkably low limits of detection (LoDs) for tumor necrosis factor-alpha (TNF-alpha), cardiac troponin I (cTnI), and interleukin-6 (IL-6), with LoDs of 9.38 fg/mL, 1.70 fg/mL, and 8.14 fg/mL, respectively. The proposed electrochemical immunosensor also exhibited high selectivity and repeatability, with relative standard deviations (RSD) of 6.39% for TNF-alpha, 2.42% for cTnI, and 2.72% for IL-6 (n = 5). Moreover, it demonstrated high sensitivity and was evaluated for serum detection using the standard addition method. The results highlight the great potential of the proposed electrochemical immunosensor for clinical applications, offering a novel approach for future utilization in clinical settings.

4.
Macromol Rapid Commun ; 44(21): e2300391, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37690003

RESUMEN

The vibrationally resolved pyrene fluorescence probe method is once popular but now languished, because the vibrationally resolved patterns of pyrene with limited sensitivity and concentration independence have not been updated for over 50 years. During investigation on the polymer interdiffusion of a latex film, it is found that a pyrene acylhydrazone whose vibrationally resolved fluorescence pattern contradictory to those reported in pyrene and most pyrene derivatives. The pyrene acylhydrazone has sensitive concentration- and polarity-dependent fluorescence spectra (the sensitivity on polarity is at most 26 times higher than the old vibrationally resolved patterns), and the sensitivity well remains when it is copolymerized in a polymer. The vibrationally resolved spectrum of this pyrene acylhydrazone is a powerful fluorescence probe, which would be as useful as the pyrene excimer probe nowadays popular.


Asunto(s)
Colorantes Fluorescentes , Polímeros , Fluorescencia , Espectrometría de Fluorescencia/métodos , Pirenos
5.
Molecules ; 28(13)2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37446859

RESUMEN

In this study, ZnAl-layered double hydroxide (ZnAl-LDH) was functionalized with 2-phenylbenzimidazole-5-sulfonic acid (PBSA) to prepare ZnAl-PBSA-LDH using a simple one-step method. The electrochemical impedance spectroscopy (EIS) result of the solution phase demonstrated excellent corrosion inhibition performance of ZnAl-PBSA-LDH. Subsequently, 0.6 wt.% ZnAl-PBSA-LDH with shielding effects and active inhibition was incorporated into the water-based epoxy (WEP) for preparing the high-performance anti-corrosion coating (6-ZPL/WEP). The EIS test illustrated that the 6-ZPL/WEP coating maintained a high low-frequency impedance modulus (|Z0.01 Hz|) after 30 days of immersion, which is nearly two orders of magnitude higher compared to that of the blank coating. These results demonstrated that ZnAl-PBSA-LDH could efficiently improve the corrosion resistance of the WEP coating. Therefore, this study introduces new insights into the use of layered double hydroxides (LDHs) in the domain of anti-corrosion.


Asunto(s)
Hidróxidos , Agua , Hidróxidos/química , Corrosión
7.
BMC Pediatr ; 23(1): 150, 2023 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-37004020

RESUMEN

BACKGROUND: The cut-off date in the education system causes a relative age difference, with developmental advantages for children who are born on the "early side" of the cut-off date and disadvantages for those born later, which is known as the relative age effect (RAE). Very few studies have examined whether there is a RAE on the development of fundamental movement skills (FMSs) in preschool children, and no studies have been conducted in China. The purpose of this study is to identify whether a RAE exists on FMS in Chinese preschool children, comparing RAEs according to gender and age. METHODS: From a total of 378 invited preschool children regularly registered at one Chinese kindergarten, a total of 288 healthy and typically developing preschoolers (4.33 ± 0.84 years-old; 56.6% boys) were included in this study. All children were required to take part in anthropometry and FMS assessments. Analysis of covariance (ANCOVA) was applied to examine the difference in each of the FMS items across quarter categories, year and gender groups, controlling for body mass index (BMI). RESULTS: For the overall sample, the data show the significant main effects on the quarter of birth factor in locomotor skills (LC; F (3, 265) = 2.811, p = 0.04, ηp2 = 0.031), object control skills (OB; F (3, 265) = 6.319, p = 0.04, ηp2 = 0.031), and total test score (TTS; F (3, 265) = 5.988, p = 0.001, ηp2 = 0.063). There were also significant differences in the age effect on all the domains of FMS (FLC (2, 265) = 100.654, p < 0.001, ηp2 = 0.432; FOB (2, 265) = 108.430, p < 0.001, ηp2 = 0.450; FTTS (2, 265) = 147.234, p < 0.001, ηp2 = 0.526) but a gender effect only in LC (F (1, 265) = 20.858; p < 0.001; ηp2 = 0.073). For gender and quarter of birth groups, RAEs in LC only exists in girls. Moreover, regarding age and quarter of birth factors, RAEs are only found at younger ages. CONCLUSIONS: This study suggests the existence of RAEs in the FMS of Chinese preschool children. Teachers need to be aware of the effect of RAEs on the FMS when approaching development, evaluation, and teaching approaches in preschools.


Asunto(s)
Pueblos del Este de Asia , Destreza Motora , Masculino , Femenino , Preescolar , Humanos , Índice de Masa Corporal , Antropometría , Movimiento
8.
ACS Appl Mater Interfaces ; 14(10): 12617-12629, 2022 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-35235285

RESUMEN

Thermal comfort is of great significance to maintain people's healthy state in physics, physiology, and psychology. Personal thermal management (PTM) that passively regulates the immediate environment around the human body has been proposed as a promising strategy to realize on-demand human thermal comfort. In this work, we propose a one-stop solution for the state of the art PTM by combining thermal shielding and thermal energy storage in a Janus-type wearable device, which is named a Janus-type hydroxyapatite-incorporated Kevlar aerogel@Kevlar aerogel supported phase-change material gel (HKA@KPG). The lower HKA with an ultralow thermal conductivity directly attached on the skin can effectively hinder heat transfer from the external environment to human skin. The upper KPG possessing a superior form stability and high energy storage capacity can absorb the heat generated by the human body to regulate the skin temperature. Both the HKA and KPG also demonstrate excellent biocompatibility. Due to its synergistic effect in thermal energy regulation, the Janus HKA@KPG has been applied in wearable PTM in static and dynamic modes to meet the thermal comfort requirements. It is anticipated that the one-stop thermal comfort solution for thermal shielding, thermal energy storage, self-supporting characteristics, wearability, and biosafety offers new possibilities for the next generation of wearable PTMs.


Asunto(s)
Durapatita , Dispositivos Electrónicos Vestibles , Calor , Humanos , Conductividad Térmica
9.
J Colloid Interface Sci ; 606(Pt 1): 223-235, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34390990

RESUMEN

Recently, two-dimensional MXene demonstrated promising advantages to improve the flame-retardant performance of composites; however, its compatibility with polymer matrix is a great concern. In this study, MXene was first functionalized with phosphorylated chitosan (PCS) to obtain the PCS-MXene nanohybrid. The resulting nanohybrid was introduced into the thermoplastic polyurethane (TPU) matrix via solution mixing followed by the hot-pressing method, affording TPU/PCS-MXene nanocomposite. The resulting nanohybrid exhibited superior compatibility with the TPU matrix, enhancing mechanical performance of the TPU/PCS-MXene nanocomposite compared to the pristine TPU and TPU/MXene nanocomposite. Besides, the flame-retardant performance of TPU/PCS-MXene nanocomposite was greatly enhanced, while the smoke emission was effectively suppressed. As only 3 wt% PCS-MXene was introduced, peak heat release rate, total heat release, and total smoke production of the composite decreased by 66.7%, 21.0%, and 27.7%, respectively, compared to the pristine TPU. Systematical characterization was then carried out to investigate the enhancement mechanism of PCS-MXene, highlighting the crucial role of PCS combined with the catalytic effect of MXene. In brief, the compatibility issues of MXene were effectively addressed, and its flame-retardancy enhanced greatly via the PCS modification, the bio-based characteristic of which, in turn greatly benefits the further development of MXene-polymer composite.


Asunto(s)
Quitosano , Retardadores de Llama , Nanocompuestos , Poliuretanos , Humo
10.
Polymers (Basel) ; 11(12)2019 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-31795478

RESUMEN

Fire and smoke suppressions of polyvinyl alcohol (PVA) aerogels are urgently required due to the serious fire hazard they present. MXene, a 2D transition-metal carbide with many excellent properties, is considered a promising synergist for providing excellent flame retardant performance. PVA/ammonium polyphosphate (APP)/transition metal carbide (MXene) composite aerogels were prepared via the freeze-drying method to enhance the flame retardancy. Thermogravimetric analysis, limiting oxygen index, vertical burning, and cone calorimeter tests were executed to investigate the thermal stability and flame retardancy of PVA/APP/MXene (PAM) composite aerogels. The results demonstrated that MXene boosted the flame retardancy of PVA-APP, and that PAM-2 (with 2.0 wt% MXene loading) passed the V-0 rating, and reached a maximum LOI value of 42%; Moreover, MXene endowed the PVA-APP system with excellent fire and smoke suppression performance, as the the peak heat release rate and peak smoke production rate were significantly reduced by 55% and 74% at 1.0 wt% MXene loading. The flame retardant mechanism was systematically studied, MXene facilitated the generation of compact intumescent residues via ita catalyst effects, thus further restraining the release of heat and smoke. This work provides a simple route to improve the flame retardancy of PVA aerogels via the synergistic effect of MXene and APP.

11.
Polymers (Basel) ; 11(12)2019 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-31835415

RESUMEN

Abstract: A series of novel bio-based form stable composite phase-change materials (fs-CPCMs) for solar thermal energy storage and management applications were prepared, using the pomelo peel flour (PPF) as the supporting matrix and poly (ethylene glycol) (PEG) or isocyanate-terminated PEG to induce a phase change. The microscopic structure, crystalline structures and morphologies, phase change properties, thermal stability, light-to-thermal conversion behavior, and thermal management characteristics of the obtained fs-CPCMs were studied. The results indicate that the obtained fs-CPCM-2 presented remarkable phase-change performance and high thermal stability. The melting latent heat and crystallization heat for fs-CPCM-2 are 143.2 J/g and 141.8 J/g, respectively, and its relative enthalpy efficiency (λ) is 87.4%, which are higher than most reported values in the related literature. The obtained novel bio-based fs-CPCM-2 demonstrated good potential for applications in solar thermal energy storage and waste heat recovery.

12.
Polymers (Basel) ; 9(11)2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-30965924

RESUMEN

Design of polymer nanocomposites has been an intense research topic in recent decades because hybrid nanomaterials are widely used in many fields. Throughout their development, there has often been a challenging issue how one can uniformly distribute nanoparticles (NPs) in a polymer matrix, avoiding their agglomeration. In this short review, we first introduce the theory of colloidal aggregation/gelation purely based on intense shear forces. Then, we illustrate a methodology for preparing polymer nanocomposites where the NPs (as fillers) are uniformly and randomly distributed inside a matrix of polymer NPs, based on intense shear-driven aggregation of binary colloids, without using any additives. Its feasibility has been demonstrated using two stable binary colloids composed of (1) poly-methyl methacrylate fillers and polystyrene NPs, and (2) graphene oxide sheets (fillers) and poly-vinylidene fluoride NPs. The mechanism leading to capturing and distribution of the fillers inside the polymer NP matrix has been illustrated, and the advantages of the proposed methodology compared with the other common methods are also discussed.

13.
Soft Matter ; 12(27): 5876-82, 2016 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-27334421

RESUMEN

A general methodology has been developed for preparing nanocomposites with uniform, random distribution of fillers in polymer matrices, purely based on intense shear-driven aggregation, while avoiding filler aggregation. This procedure is demonstrated for a binary colloid composed of graphene oxide (GO) sheets and poly-vinylidene fluoride (PVDF) nanoparticles (NPs), both negatively charged and stable at rest. On the other hand, the PVDF NPs are shear-active (i.e. aggregation occurs under intensive shear), while the GO sheets are shear-inactive. It is found that when the two suspensions are mixed and the resulting binary colloid is forced to pass through a microchannel (MC) device (at a very high shear rate, G = 1.2 × 10(6) s(-1)), the shear-inactive GO sheets are captured and well distributed inside the PVDF NP clusters or gels. In addition, it is shown that in order to have 100% capture efficiency for the GO sheets, a minimum solid content of the binary colloid is required, which can be identified experimentally as the minimum leading to gelation after passing through the MC only one time.

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