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1.
Light Sci Appl ; 13(1): 165, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009609

RESUMEN

An immature understanding of the mechanisms of persistent luminescence (PersL) has hindered the development of new persistent luminescent materials (PersLMs) with increased brightness. In this regard, in-situ direct current (DC) electric field measurements were conducted on a layered structure composed of the SrAl2O4:Eu2+,Dy3+ phosphor, and an electrode. In this study, the photoluminescence (PL) and afterglow properties were investigated with respect to voltage by analyzing the current signal and thermoluminescence (TL) spectroscopy. The intensity of PersL increased due to a novel phenomenon known as "external electric field stimulated enhancement of initial brightness of afterglow". This dynamic process was illustrated via the use of a rate equation approach, where the electrons trapped by the ultra-shallow trap at 0.022 eV could be transferred through the conduction band during long afterglow. The afterglow intensity could reach 0.538 cd m-2 at a 6 V electric voltage. The design of an electric field stimulation technique enables the enhancement of the intensity of PersLMs and provides a new perspective for exploring the fundamental mechanics of certain established PersLMs.

2.
Materials (Basel) ; 17(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38730838

RESUMEN

Multi-material additive manufacturing using heterogeneous powders as raw materials is one of the important development directions of metal additive manufacturing technology. The evaporation behavior of heterogeneous powders in the selective laser melting (SLM) process has a significant influence on the accuracy of chemical composition control and the quality of the final product. In this paper, the fusion process of Fe20Mn (80 wt.% Fe and 20 wt.% Mn) heterogeneous powder, Fe and Mn elemental powders, and Fe20Mn pre-alloyed powder is numerically simulated using FLOW-3D® software and partially validated through SLM experimental results. The morphology and the characteristics of the flow field and temperature field in the melt pool for four kinds of powder materials are analyzed. The influence of the elemental evaporation behavior of different powders on the mass loss of the Mn element is discussed. The results show that the excessive accumulation of heat increases the maximum temperature of the melt pool, thus increasing mass loss. The Fe20Mn heterogeneous powder has a wider heat-affected zone and a higher peak value of temperature, nearly 400 K higher than that of the Fe20Mn pre-alloyed powders, which exhibits an intensive evaporation behavior. The mass loss of the Mn element obtained from the SLM experiment for Fe20Mn heterogeneous powders forming parts is more than the Fe20Mn pre-alloyed powders' forming parts for different laser powers, up to 17 wt.% at P = 120 W. This tendency is consistent with the numerical analysis of the effect of evaporation behavior of Fe-Mn heterogeneous powder during the SLM process. This study provides the necessary theoretical reference and process guidance for realizing the precise control of the SLM composition of a heterogeneous powder in multi-material additive manufacturing caused by evaporation behavior.

3.
ACS Appl Mater Interfaces ; 14(39): 44622-44631, 2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-36129520

RESUMEN

Near-infrared (NIR) long persistent luminescent (LPL) materials have attracted the interest of many researchers as they have potential applications in many aspects. However, majority of studies on Cr3+ ion-doped LPL materials have focused on Cr3+ in an octahedral site, and the luminescence is limited to the short-wavelength NIR-I region (700-900 nm), which is detrimental to fully explore Cr3+ ion-doped LPL materials with potential applications. In this work, a novel ultra-broadband NIR LPL material, Na2CaGe6O14 (NCGO):x%Cr3+, was successfully designed and synthesized, covering the luminescence range of 600-1200 nm and having the best afterglow duration of more than 10 h. Combining the luminescence lifetime with the low-temperature spectrum, it was concluded that the luminescence of NCGO:Cr3+ consists of the co-emission of Cr3+ in octahedra and tetrahedra. And it was confirmed by electron paramagnetic resonance (EPR) spectrum and X-ray absorption near-edge spectrum (XANES). The application prospects of NCGO:x%Cr3+ in many aspects were investigated in detail. This work could not only give a reference for researchers to study Cr3+ luminescence in multiple coordination but also provide a new strategy for obtaining new ultra-broadband NIR LPL materials.

4.
Nutrients ; 14(16)2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-36014880

RESUMEN

Increased oxidative stress and platelet apoptotic in middle-aged and elderly adults are important risk factors for atherosclerotic cardiovascular disease (ASCVD). Therefore, it is of great significance to control the oxidative stress and platelet apoptosis in middle-aged and elderly adults. Previous acute clinical trials have shown that water-soluble tomato concentrate (WSTC) from fresh tomatoes could exert antiplatelet benefits after 3 h or 7 h, but its effects on platelet apoptosis and oxidative stress are still unknown, especially in healthy middle-aged and elderly adults. This current study aimed to examine the efficacies of WSTC on platelet apoptosis and oxidative stress in healthy middle-aged and elderly adults via a randomized double-blinded placebo-controlled crossover clinical trial (10 weeks in total). A total of 52 healthy middle-aged and elderly adults completed this trial. The results showed that WSTC could increase the serum total antioxidant capacity levels (p < 0.05) and decrease the serum malondialdehyde levels (p < 0.05) after a 4-week WSTC supplementation in healthy middle-aged and elderly adults. Platelet endogenous reactive oxygen species generation (p < 0.05), mitochondrial membrane potential dissipation (p < 0.05) and phosphatidylserine exposure (p < 0.05) were attenuated. In addition, our present study also found that WSTC could inhibit platelet aggregation and activation induced by collagen or ADP after intervention (p < 0.05), while having no effects on adverse events (p > 0.05). The results suggest that WSTC can inhibit oxidative stress and its related platelet apoptosis, which may provide a basis for the primary prevention of WSTC in ASCVD.


Asunto(s)
Antioxidantes , Solanum lycopersicum , Adulto , Anciano , Antioxidantes/farmacología , Apoptosis , Suplementos Dietéticos , Método Doble Ciego , Humanos , Persona de Mediana Edad , Estrés Oxidativo , Agua/farmacología
5.
Front Nutr ; 9: 891241, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35719156

RESUMEN

Background and Aims: Platelets are linked to atherosclerotic development and pathological thrombosis. Single dose of water-soluble tomato extract (WTE) which is a natural extraction can exert anti-platelet effects after 3 or 7 h in British healthy people. However, the effects of WTE supplementation on platelet function in Chinese healthy middle-aged and older individuals have not been studied, and the effects or safety of 4-week WTE supplementation also remain unclear. The present study aims to determine the effects of WTE on platelet function, and explore the safety of 4-week WTE supplementation in Chinese healthy middle-aged and older individuals. Methods: A randomized, double-blinded, and crossover clinical trial was conducted. Firstly, 105 individuals were randomly divided into two groups that received WTE (150 mg/day) or placebo for 4 weeks. Then, after a washout period of 2 weeks, two groups exchanged groups and continued for another 4-week intervention. Platelet aggregation, P-selectin, activated GPIIbIIIa, plasma platelet factor 4 (PF4), ß-thromboglobulin (ß-TG), and thromboxane B2 (TXB2) were tested at baseline, 4, 6, and 10 weeks. Results: Compared with the placebo group, 150 mg/day WTE supplement for 4 weeks significantly reduced ADP-induced or collagen-induced platelet aggregation (-10.8 ± 1.8 or -3.9 ± 1.5%, P < 0.05), ADP-induced or collagen-induced platelet P-selectin expression (-6.9 ± 1.5 or -6.6 ± 1.3%, P < 0.05), ADP-induced or collagen-induced activated GPIIbIIIa (-6.2 ± 2.0 or -3.8 ± 2.0%, P < 0.05). Besides, 4-week intervention of 150 mg WTE per day also resulted in significant reductions in plasma PF4 (-120.6 ± 33.2 ng/mL, P < 0.05) and ß-TG (-129.7 ± 27.5 ng/mL, P < 0.05) and TXB2 (-42.0 ± 4.0 ng/mL, P < 0.05), while had no effects on coagulation function and liver or renal function. Interestingly, 2-week washout period is enough to reverse the inhibitory effect of 4-week WTE supplementation on platelet function. Conclusion: WTE supplementation for 4 weeks could moderately reduce platelet activation, aggregation, and granule secretion in Chinese healthy middle-aged and older individuals, and these effects are safe. After 2-week washout period, the inhibitory effect of 4-week WTE on platelet function can be eliminated. Clinical Trial Registration: [http://www.chictr.org.cn/], identifier [ChiCTR-POR-17012927].

6.
EBioMedicine ; 70: 103533, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34392146

RESUMEN

BACKGROUND: Dyslipidemia induces platelet hyperactivation and hyper-aggregation, which are linked to thrombosis. Anthocyanins could inhibit platelet function in vitro and in mice fed high-fat diets with their effects on platelet function in subjects with dyslipidemia remained unknown. This study aimed to investigate the effects of different doses of anthocyanins on platelet function in individuals with dyslipidemia. METHODS: A double-blind, randomized, controlled trial was conducted. Ninety-three individuals who were initially diagnosed with dyslipidemia were randomly assigned to placebo or 40, 80, 160 or 320 mg/day anthocyanin groups. The supplementations were anthocyanin capsules (Medox, Norway). Platelet aggregation by light aggregometry of platelet-rich plasma, P-selectin, activated GPⅡbⅢa, reactive oxygen species (ROS), and mitochondrial membrane potential were tested at baseline, 6 weeks and 12 weeks. FINDINGS: Compared to placebo group, anthocyanins at 80 mg/day for 12 weeks reduced collagen-induced platelet aggregation (-3.39±2.36%) and activated GPⅡbⅢa (-8.25±2.45%) (P < 0.05). Moreover, compared to placebo group, anthocyanins at 320 mg/day inhibited collagen-induced platelet aggregation (-7.05±2.38%), ADP-induced platelet aggregation (-7.14±2.00%), platelet ROS levels (-14.55±1.86%), and mitochondrial membrane potential (7.40±1.56%) (P < 0.05). There were dose-response relationships between anthocyanins and the attenuation of platelet aggregation, mitochondrial membrane potential and ROS levels (P for trend <0.05). Furthermore, significantly positive correlations were observed between changes in collagen-induced (r = 0.473) or ADP-induced (r = 0.551) platelet aggregation and ROS levels in subjects with dyslipidemia after the 12-week intervention (P < 0.05). INTERPRETATION: Anthocyanin supplementation dose-dependently attenuates platelet function, and 12-week supplementation with 80 mg/day or more of anthocyanins can reduce platelet function in individuals with dyslipidemia. FUNDING: None.


Asunto(s)
Antocianinas/farmacología , Dislipidemias/tratamiento farmacológico , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Adulto , Anciano , Antocianinas/administración & dosificación , Antocianinas/uso terapéutico , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Selectina-P/sangre , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/uso terapéutico , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Especies Reactivas de Oxígeno/sangre
7.
Nutrients ; 13(7)2021 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-34202823

RESUMEN

Little is known about which currently available a priori dietary indexes provide best guidance for reducing cardiometabolic risk factors (CMRF) among hyperlipidemic patients. This study was designed to compare the associations between four a priori dietary indexes, including Diet Balance Index (DBI-16), Chinese Healthy Eating Index (CHEI), Mediterranean Diet Score (MDS) and Dietary Approaches to Stop Hypertension (DASH) and CMRF among hyperlipidemic patients. A total of 269 participants were enrolled into the cross-sectional study. DBI-16, CHEI, MDS, and DASH scores were calculated using established methods. CMRF was measured using standard methods. DBI-total scores (DBI-TS) were inversely associated with triglyceride concentrations and TC:HDL-C ratio, and positively associated with HDL-C and ApoA1 concentrations (all p < 0.05), while the results for DBI-low bound scores (DBI-LBS) were opposite. DBI-high bound scores (DBI-HBS) and DASH scores were positively and inversely associated with glucose concentrations, respectively (both p < 0.05). Higher diet quality distance (DQD) was positively associated with higher TC, LDL-C and ApoB concentrations, and TC:HDL-C and LDL-C:HDL-C ratios, and lower HDL-C and ApoA1 concentrations and ApoA1:ApoB ratio (all p < 0.05). CHEI scores were inversely associated with triglyceride concentrations (p = 0.036). None of the dietary indexes was associated with blood pressures. DBI-16 provided most comprehensive evaluations of the overall diet quality and balance for optimizing cardiometabolic health among hyperlipidemic individuals.


Asunto(s)
Dieta Saludable/métodos , Hiperlipidemias/dietoterapia , Evaluación Nutricional , Apolipoproteína A-I/sangre , Factores de Riesgo Cardiometabólico , HDL-Colesterol/sangre , Estudios Transversales , Dieta Mediterránea/estadística & datos numéricos , Enfoques Dietéticos para Detener la Hipertensión/estadística & datos numéricos , Método Doble Ciego , Femenino , Humanos , Hiperlipidemias/sangre , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Reproducibilidad de los Resultados , Triglicéridos/sangre
8.
Clin Nutr ; 40(4): 1871-1878, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33131908

RESUMEN

BACKGROUND & AIMS: Plasma ceramides have been identified as novel risk factors for metabolic and cardiovascular diseases. We aimed to evaluate the effects of dietary anthocyanins on plasma ceramides and to disentangle whether the alterations in ceramides could be related with those in other cardiometabolic risk factors in the dyslipidemia. METHODS: In a randomized double-blinded placebo-controlled trial, 176 eligible dyslipidemia subjects were randomly assigned into four groups receiving placebo, 40, 80, or 320 mg/day anthocyanins, respectively for 12 weeks. RESULTS: A total of 169 subjects completed the study. After 12-week intervention, dietary anthocyanins dose-dependently reduced plasma concentrations of all six ceramide species in the dyslipidemia subjects (all Ptrend values < 0.05). Specifically, 320 mg/day anthocyanins effectively lowered plasma N-palmitoylsphingosine (Cer 16:0, mean change: -28.3 ± 41.2 versus 2.9 ± 38.2, nmol/L, P = 0.018) and N-tetracosanoylsphingosine (Cer 24:0, mean change: -157.1 ± 493.9 versus 10.7 ± 439.9, nmol/L, P = 0.002) compared with the placebo. The declines in plasma Cer 16:0 and Cer 24:0 were significantly correlated with the decreases in plasma non-high-density lipoprotein cholesterol (nonHDL-C, Spearman's r = 0.32, P = 0.040 for Cer 16:0; Spearman's r = 0.35, P = 0.026 for Cer 24:0), apolipoprotein B (Spearman's r = 0.33, P = 0.031 for Cer 16:0; Spearman's r = 0.48, P = 0.002 for Cer 24:0), and total cholesterol (Spearman's r = 0.34, P = 0.026 for Cer 16:0; Spearman's r = 0.31, P = 0.042 for Cer 24:0) after 12-week 320 mg/day anthocyanin administration. Besides, we found that anthocyanins at 320 mg/day also markedly enhanced cholesterol efflux capacity in the dyslipidemia, the changes of which were positively associated with the reductions in Cer 16:0 (Spearman's r = 0.42, P = 0.006) independent of HDL-C and apolipoprotein A-I. CONCLUSIONS: Reductions in plasma Cer 16:0 and Cer 18:0 after 12-week anthocyanin intervention were dose-dependently associated with improvements in plasma lipids and cholesterol efflux capacity in the dyslipidemia. CLINICAL TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov with the identifier No. NCT03415503.


Asunto(s)
Antocianinas/farmacología , Ceramidas/sangre , Colesterol/sangre , Suplementos Dietéticos , Dislipidemias/tratamiento farmacológico , Lípidos/sangre , Adulto , Anciano , Antocianinas/sangre , China , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Dislipidemias/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad
9.
Zhongguo Gu Shang ; 29(8): 764-766, 2016 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-29282939

RESUMEN

OBJECTIVE: To summarize clinical result of the modified posterior approach for the treatment of the mid and distal segment humeral fractures. METHODS: Between January 2006 and December 2010, 26 patients with the mid and distal segment humeral fractures were treated with the open reduction and plate fixation by the modified posterior approach including 17 males and 9 females with an average of (37.1±1.5) years old ranging from 24 to 50 years old. The time from humeral fractures to operation were from 8 hours to 6 days with an average of (3.3±0.6) d. The elbow function were assessed by Morrey-Bryan. RESULTS: There was no procedure related complications occurred. No neurologic injury and wound infection after operation occurred. All patients were followed up from 22 to 48 months with an average of (30.1±1.6) months. The humeral fractures were confirmed healing. The clinical results of Morrey and Bryan were excellent in 19 cases (94.6±1.8), good in 7 cases (86.5±1.2). CONCLUSIONS: The modified posterior approach avoided injury of triceps muscle and improved postoperative triceps function. The technique may be particularly useful in the treatment of the mid and distal segment humeral fractures.


Asunto(s)
Placas Óseas , Fijación Interna de Fracturas/métodos , Fracturas del Húmero/cirugía , Adulto , Articulación del Codo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético , Resultado del Tratamiento
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