Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
1.
J Am Chem Soc ; 146(32): 22777-22786, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39096316

RESUMEN

Low-temperature operation poses a significant challenge for current commercial rechargeable lithium-ion batteries (LIBs). Organic polymer electrode materials, exhibiting a nonintercalation redox mechanism, offer a viable solution to mitigate the decline in electrochemical performance at low temperatures in LIBs. Herein, a radical polymer P(DATPAPO-TPA) with a conjugated nitrogen-rich triphenylamine derivative as the backbone and high-density nitroxide pendants has been synthesized. Due to the large interstitial spaces between adjacent structural units and polymer chains, resulting from the significant torsion angle between the benzene rings in the P(DATPAPO-TPA) skeleton, ions could effectively transport. This structural feature demonstrated a notable discharge capacity of 143.3 mA h·g-1 and a high charge-discharge plateau at ∼3.75 V vs Li+/Li, outperforming most reported radical polymer cathode materials. In addition, its capacity retention could reach 83.1% after 2000 cycles at an ultrahigh current density of 50 C, showing excellent rate capability and promising cyclability. Also notable was P(DATPAPO-TPA)'s favorable low-temperature performance that maintains a high discharge capacity of 139.2 mA h·g-1 at 0 °C. The synthesized P(DATPAPO-TPA) is a tangible illustration of a viable design strategy for low-temperature electrode materials, thereby contributing to broadening applications for radical polymer electrode materials.

2.
BMC Cardiovasc Disord ; 24(1): 341, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969996

RESUMEN

BACKGROUND: The study evaluated the performance of the Mindray N-terminal pro-B-type natriuretic peptide (NT-proBNP) in a healthy population in China, focusing on creating a reference range for future clinical applications adjusted according to different demographics. METHODS: The study measured NT-proBNP in 2277 healthy individuals. We analyzed age and sex-stratified data, performed precision, accuracy, linearitcvy, and detection limit studies, and evaluated method comparison and consistency between Roche and Mindray assays on 724 serum samples. We used Excel 2010, Medcalc, and GraphPad Prism 9. RESULTS: In males, the 97.5th centile NT-proBNP concentration at age < 45, 45 to 54, 55 to 64, 65 to 74 and ≧ 75 were 89.4 ng/L, 126 ng/L, 206 ng/L, 386 ng/L and 522 ng/L, respectively. In females, the concentration of NT-proBNP at the same age was 132 ng/L, 229 ng/L, 262 ng/L, 297 ng/L and 807 ng/L, respectively. The repeatability precision coefficient of variation (CV%) for NT-proBNP was between 0.86 and 1.65 in analytical performance. In contrast, the reproducibility precision (CV%) for NT-proBNP was between 1.52 and 3.22, respectively. The study found a bias of accuracy of 3.73% in low-value samples (concentration: 148.69) and 7.31% in high-value samples (concentration: 1939.08). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 125 ng/L were 96.6%, 92.3%, 84.2%, and 98.5%, respectively. In contrast, those of 300 ng/L were 94.0%, 98.2%, 95.7% and 97.5%, respectively. CONCLUSIONS: The Mindray NT-proBNP assay showed increased levels in both males and females with age, with higher levels in women. It performs well and aligns with manufacturer specifications. We recommend adjusting cutoff values based on demographic factors.


Asunto(s)
Biomarcadores , Péptido Natriurético Encefálico , Fragmentos de Péptidos , Valor Predictivo de las Pruebas , Humanos , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Masculino , Femenino , Persona de Mediana Edad , Anciano , Biomarcadores/sangre , Reproducibilidad de los Resultados , Adulto , China , Valores de Referencia , Factores Sexuales , Factores de Edad , Voluntarios Sanos , Anciano de 80 o más Años , Adulto Joven , Límite de Detección
4.
Materials (Basel) ; 17(7)2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38612154

RESUMEN

Controlling infrared thermal radiations can significantly improve the environmental adaptability of targets and has attracted increasing attention in the field of thermal camouflage. Thermal emitters based on Ge2Sb2Te5 (GST) can flexibly change their radiation energy by controlling the reversible phase transition of GST, which possesses fast switching speed and low power consumption. However, the feasibility of the dynamic regulation of GST emitters lacks experimental and simulation verification. In this paper, we propose an electrically tunable thermal emitter consisting of a metal-insulator-metal plasmonic metasurface based on GST. Both optical and thermal simulations are conducted to optimize the structural parameters of the GST emitter. The results indicate that this emitter possesses large emissivity tunability, wide incident angle, polarization insensitivity, phase-transition feasibility, and dynamic thermal camouflage capability. Therefore, this work proposes a reliable optimization method to design viable GST-based thermal emitters. Moreover, it provides theoretical support for the practical application of phase-change materials in dynamic infrared thermal camouflage technology.

5.
Acta cir. bras ; 38: e381023, 2023. ilus, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1439116

RESUMEN

Purpose: To investigate the role of cyanidin-3-O-glucoside (C3G) in renal ischemia/reperfusion (I/R) injury and the potential mechanisms. Methods: Mouse models were established by clamping the left renal vessels, and in vitro cellular models were established by hypoxic reoxygenation. Results: Renal dysfunction and tissue structural damage were significantly higher in the I/R group. After treatment with different concentrations of C3G, the levels of renal dysfunction and tissue structural damage decreased at different levels. And its protective effect was most pronounced at 200 mg/kg. The use of C3G reduced apoptosis as well as the expression of endoplasmic reticulum stress (ERS)-related proteins. Hypoxia/reoxygenation (H/R)-induced apoptosis and ERS are dependent on oxidative stress in vitro. In addition, both AG490 and C3G inhibited the activation of JAK/STAT pathway and attenuated oxidative stress, ischemia-induced apoptosis and ERS. Conclusions: The results demonstrated that C3G blocked renal apoptosis and ERS protein expression by preventing reactive oxygen species (ROS) production after I/R via the JAK/STAT pathway, suggesting that C3G may be a potential therapeutic agent for renal I/R injury.


Asunto(s)
Animales , Ratones , Daño por Reperfusión , Sistema de Señalización de MAP Quinasas , Quinasas Janus , Lesión Renal Aguda/fisiopatología , Isquemia , Antocianinas/análisis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA