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1.
Adv Mater ; : e2310822, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38044876

RESUMO

The electrosynthesis of multi-carbon chemicals from excess CO2 is an area of great interest for research and commercial applications. However, improving both the yield of CO2 -to-ethanol conversion and the stability of the catalyst at the same time is proving to be a challenging issue. Here we propose to stabilize active Cu(I) and In dual sites with sulfur defects through an electro-driven intercalation strategy, which leads to the delocalization of electron density that enhances orbital hybridizations between the Cu-C and In-H bonds. Hence, the energy barrier for the rate-limiting *CHO formation step is reduced toward the key *OCHCHO* formation during ethanol production, which is also facilitated by the combined Cu site enabling C-C coupling and In site with a higher oxygen affinity based on both thermodynamic and kinetic calculations. Accordingly, such dual-site catalyst achieves a high partial current density toward ethanol of 409 ± 15 mA/cm2 for over 120 hours. Furthermore, a scaled-up flow cell is assembled with an industrial-relevant current of 5.7 A for over 36 hours, in which the carbon loss is less than 2.5% and single-pass carbon efficiency is around 19%. This article is protected by copyright. All rights reserved.

2.
BMC Oral Health ; 23(1): 782, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875820

RESUMO

BACKGROUND: Oral health and frailty are significantly related and should be well examined, especially in late life. Few studies have explored the relationship of oral health knowledge, attitudes, and practices with frailty and examined sociodemographic variations in this association. This study aimed to examine the association between oral health knowledge, attitudes, practices and frailty, with a special focus on comparing differences in their association among the Chinese community-dwelling older population. METHODS: This study included 4218 community-dwelling older adults (aged ≥ 60 years) who participated in a cross-sectional survey. Sociodemographic characteristics, oral health knowledge, attitudes, practices, and frail status (non-frailty, pre-frailty, and frailty) were collected with a face-to-face questionnaire-based interview. Multivariate logistic regression models were used to evaluate the association of oral health knowledge, attitudes, and practices with frailty. RESULTS: Of the 4218 participants, 36.2% (n = 1527) and 18.8% (n = 792) were classified as pre-frailty and frailty. Age, gender and educational attainments differences existed in the association of oral health knowledge with frailty. Urban-rural differences in the association of oral health knowledge and practices with frailty were also found. Specifically, oral health knowledge was significantly related to frailty only among participants aged 70-79 years (adjusted odds ratio [95% confidence interval]) (1.08 [1.02-1.15]), females (1.05 [1.00-1.10]), rural residents (1.06 [1.01-1.12]), and those who were primary school and lower education (1.06 [1.01-1.11]), whereas oral health practices were related to frailty only among urban participants (0.96 [0.92-1.00]). CONCLUSION: This study confirmed the different associations of oral health knowledge and practices with frailty among community-dwelling older people in China. Further research is needed to better understand the abovementioned differences and public health strategies are required to improve oral health literacy and thereby contain the development of frailty in later life.


Assuntos
Fragilidade , Idoso , Feminino , Humanos , Fragilidade/epidemiologia , Idoso Fragilizado , Vida Independente , Saúde Bucal , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , China , Avaliação Geriátrica
3.
JACS Au ; 3(8): 2046-2061, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37654582

RESUMO

Electrochemical CO2 upgrade offers an artificial route for carbon recycling and neutralization, while its widespread implementation relies heavily on the simultaneous enhancement of mass transfer and reaction kinetics to achieve industrial conversion rates. Nevertheless, such a multiscale challenge calls for trans-scale electrode engineering. Herein, three scales are highlighted to disclose the key factors of CO2 electrolysis, including triple-phase boundaries, reaction microenvironment, and catalytic surface coordination. Furthermore, the advanced types of electrolyzers with various electrode design strategies are surveyed and compared to guide the system architectures for continuous conversion. We further offer an outlook on challenges and opportunities for the grand-scale application of CO2 electrolysis. Hence, this comprehensive Perspective bridges the gaps between electrode research and CO2 electrolysis practices. It contributes to facilitating the mixed reaction and mass transfer process, ultimately enabling the on-site recycling of CO2 emissions from industrial plants and achieving net negative emissions.

4.
Int J Med Sci ; 20(8): 1009-1023, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37484808

RESUMO

Ischemic stroke (IS) is the majority of strokes which remain the second leading cause of deaths in the last two decades. Circulating microRNAs (miRNAs) have been suggested as potential diagnostic and therapeutic tools for IS by previous studies analyzing their differential expression. However, inconclusive and controversial conclusions of these results have to be addressed. In this study, comprehensive analysis and real-world validation were performed to assess the associations between circulating miRNAs and IS. 29 studies with 112 miRNAs were extracted after manual selection and filtering, 12 differentially expressed miRNAs were obtained from our results of meta-analysis. These miRNAs were evaluated in 20 IS patients, compared to 20 healthy subjects. 4 miRNAs (hsa-let-7e-5p, hsa-miR-124-3p, hsa-miR-17-5p, hsa-miR-185-5p) exhibited the significant expression level in IS patient plasma samples. Pathway and biological process enrichment analysis for the target genes of the 4 validated miRNAs identified cellular senescence and neuroinflammation as key post-IS response pathways. The results of our analyses closely correlated with the pathogenesis and implicated pathways observed in IS subjects suggested by the literature, which may provide aid in the development of circulating diagnostic or therapeutic targets for IS patients.


Assuntos
MicroRNA Circulante , AVC Isquêmico , MicroRNAs , Acidente Vascular Cerebral , Humanos , MicroRNAs/metabolismo , Biomarcadores
5.
BMC Geriatr ; 23(1): 267, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37142945

RESUMO

BACKGROUND: This study aimed to explore whether and how self-rated health, depression and functional ability interactively associated with loneliness using a sample group of older adults residing in China rural communities. METHODS: Data on socio-demographic information, self-rated health, depressive symptoms, functional ability and loneliness (quantified via a single question) were collected from 1009 participants. Cross-tabulations with chi-square test, bivariate correlations, and Classification and Regression Tree (CART) models were employed for analysis. RESULTS: We found that 45.1% of the participants were classified as lonely. Our results gain insight into the hierarchical order of predictors for the presence of loneliness, suggesting that there was a significant interaction between functional ability and depressive symptoms while self-rated health was not a significant factor. The probability of loneliness increased with the combination of limited functional ability and depression, and varied with different interaction of functional ability, depressive symptoms, and marital status, respectively. Notably, while there were some differences, similar associations were observed among older male and female respondents. CONCLUSION: To delay or reduce loneliness, early detection which focuses on older people who report limitations in functional ability, depression, and being female, offers opportunities to start early interventions. Our findings might be helpful not only in designing and implementing loneliness prevention programs but also in improving healthcare for older rural community-dwelling people.


Assuntos
Vida Independente , Solidão , Humanos , Idoso , Depressão/diagnóstico , Depressão/epidemiologia , População Rural , Atividades Cotidianas
6.
Front Nutr ; 9: 1001922, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466415

RESUMO

Background: The prospective association between plasma Se and stroke risk remains inconclusive. The relationship between Se and ischemic stroke among a low circulating Se status population deserves more attention, especially for Chinese people who were a high-risk group for Se deficiency. Objective: The relationship between plasma Se concentration and ischemic stroke risk in a large-scale Chinese community-based population and any potential effect modifiers were investigated. Methods: A nested, case-control study, using data from the "China H-type Hypertension Registry Study" were conducted. A total of 1,904 first ischemic stroke cases and 1,904 controls matched for age, sex, and village were included in this study. The association between plasma Se and first ischemic stroke was evaluated by conditional logistic regression analyses. Results: The median value of plasma Se was 65.8 µg/L among total participants. Overall, a significant inverse relationship between plasma Se and first ischemic stroke risk was found (per SD increment; adjusted OR: 0.87; 95% CI: 0.80 and 0.95). Accordingly, a significantly lower risk of first ischemic stroke was found in participants in quartile 3 (65.8-<77.8 µg/L) (adjusted OR: 0.78; 95% CI: 0.63 and 0.96) and quartile 4 (≥77.8 µg/L) (adjusted OR: 0.76; 95% CI: 0.59 and 0.96), compared with those in quartile 1 (<56.0 µg/L). Furthermore, a significantly lower ischemic stroke risk was found in those with lower low-density lipoprotein cholesterol (LDL-C) levels (<3.4 vs. ≥3.4 mmol/L; P for interaction = 0.015) or those with lower homocysteine levels (<12.1 (median) vs. ≥12.1 µmol/L; P for interaction = 0.027) at baseline. Conclusion: Plasma Se was significantly inversely associated with the risk of first ischemic stroke among a large-scale Chinese community-based population (most adults with hypertension and elevated total homocysteine), especially among those with lower LDL-C and lower homocysteine levels.

7.
Adv Mater ; 34(49): e2207344, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36177699

RESUMO

Aqueous Zn-ion batteries are well regarded among a next-generation energy-storage technology due to their low cost and high safety. However, the unstable stripping/plating process leading to severe dendrite growth under high current density and low temperature impede their practical application. Herein, it is demonstrated that the addition of 2-propanol can regulate the outer solvation shell structure of Zn2+ by replacing water molecules to establish a "eutectic solvation shell", which provides strong affinity with the Zn (101) crystalline plane and fast desolvation kinetics during the plating process, rendering homogeneous Zn deposition without dendrite formation. As a result, the Zn anode exhibits promising cycle stability over 500 h under an elevated current density of 15 mA cm-2 and high depth of discharge of 51.2%. Furthermore, remarkable electrochemical performance is achieved in a 150 mAh Zn|V2 O5 pouch cell over 1000 cycles at low temperature of -20 °C. This work not only offers a new strategy to achieve excellent performance of aqueous Zn-ion batteries under harsh conditions, but also reveals electrolyte structure designs that can be applied in related energy storage and conversion fields.

8.
Adv Mater ; 34(38): e2204637, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35948461

RESUMO

Electrochemical CO2 reduction to CO is a potential sustainable strategy for alleviating CO2 emission and producing valuable fuels. In the quest to resolve its current problems of low-energy efficiency and insufficient durability, a dual-scale design strategy is proposed by implanting a non-noble active Sn-ZnO heterointerface inside the nanopores of high-surface-area carbon nanospheres (Sn-ZnO@HC). The metal d-bandwidth tuning of Sn and ZnO alters the extent of substrate-molecule orbital mixing, facilitating the breaking of the *COOH intermediate and the yield of CO. Furthermore, the confinement effect of tailored nanopores results in a beneficial pH distribution in the local environment around the Sn-ZnO nanoparticles and protects them against leaching and aggregating. Through integrating electronic and nanopore-scale control, Sn-ZnO@HC achieves a quite low potential of -0.53 V vs reversible hydrogen electrode (RHE) with 91% Faradaic efficiency for CO and an ultralong stability of 240 h. This work provides proof of concept for the multiscale design of electrocatalysts.

9.
Nat Commun ; 13(1): 2486, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513361

RESUMO

CO2 electroreduction reaction offers an attractive approach to global carbon neutrality. Industrial CO2 electrolysis towards formate requires stepped-up current densities, which is limited by the difficulty of precisely reconciling the competing intermediates (COOH* and HCOO*). Herein, nano-crumples induced Sn-Bi bimetallic interface-rich materials are in situ designed by tailored electrodeposition under CO2 electrolysis conditions, significantly expediting formate production. Compared with Sn-Bi bulk alloy and pure Sn, this Sn-Bi interface pattern delivers optimum upshift of Sn p-band center, accordingly the moderate valence electron depletion, which leads to weakened Sn-C hybridization of competing COOH* and suitable Sn-O hybridization of HCOO*. Superior partial current density up to 140 mA/cm2 for formate is achieved. High Faradaic efficiency (>90%) is maintained at a wide potential window with a durability of 160 h. In this work, we elevate the interface design of highly active and stable materials for efficient CO2 electroreduction.

10.
Chem Soc Rev ; 51(8): 2917-2938, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35285470

RESUMO

Porous organic polymers (POPs), a versatile class of materials that possess many tunable properties such as high chemical absorptivity and ionic conductivity, are emerging candidate electrode materials, permselective membranes, ionic conductors, interfacial stabilizers and functional precursors to synthesize advanced porous carbon. Based on their crystal structure features, the emerging POPs can be classified into two subclasses: amorphous POPs (hyper cross-linked polymers, polymers with intrinsic microporosity, conjugated microporous polymers, porous aromatic frameworks, etc.) and crystalline POPs (covalent organic frameworks, etc.). This tutorial review provides a brief introduction of different types of POPs in terms of their classification and functions for tackling the remaining challenges in various types of Li-chemistry-based batteries. In situ and ex situ characterization studies are also discussed to highlight their importance and applicability for the structural investigation of POPs to reveal the underlying mechanism of POPs over the course of the electrochemical process. Although some revolutionary advances have been achieved, the development of POPs in Li-chemistry-based batteries is still in its infancy. Perspectives regarding future application and mechanistic insights of POPs in battery studies are outlined at the end.

11.
Angew Chem Int Ed Engl ; 61(23): e202117703, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35233896

RESUMO

The construction of safe and environmentally-benign solid-state electrolytes (SSEs) with intrinsic hydroxide ion-conduction for flexible zinc-air batteries is highly desirable yet extremely challenging. Herein, hierarchically nanostructured CCNF-PDIL SSEs with reinforced concrete architecture are constructed by nanoconfined polymerization of dual-cation ionic liquid (PDIL, concrete) within a robust three-dimensional porous cationic cellulose nanofiber matrix (CCNF, reinforcing steel), where plenty of penetrating ion-conductive channels are formed and undergo dynamic self-rearrangement under different hydrated levels. The CCNF-PDIL SSEs synchronously exhibit good flexibility, mechanical robustness, superhigh ion conductivity of 286.5 mS cm-1 , and decent water uptake. The resultant flexible solid-state zinc-air batteries deliver a high-power density of 135 mW cm-2 , a specific capacity of 775 mAh g-1 and an ultralong cycling stability with continuous operation of 240 hours for 720 cycles, far outperforming those of the state-of-the-art solid-state batteries. The marriage of biomaterials with the diversity of ionic liquids creates enormous opportunities to construct advanced SSEs for solid-state batteries.

12.
J Am Chem Soc ; 143(18): 6855-6864, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33852301

RESUMO

Electrochemical CO2 reduction (CO2RR) using renewable energy sources represents a sustainable means of producing carbon-neutral fuels. Unfortunately, low energy efficiency, poor product selectivity, and rapid deactivation are among the most intractable challenges of CO2RR electrocatalysts. Here, we strategically propose a "two ships in a bottle" design for ternary Zn-Ag-O catalysts, where ZnO and Ag phases are twinned to constitute an individual ultrafine nanoparticle impregnated inside nanopores of an ultrahigh-surface-area carbon matrix. Bimetallic electron configurations are modulated by constructing a Zn-Ag-O interface, where the electron density reconfiguration arising from electron delocalization enhances the stabilization of the *COOH intermediate favorable for CO production, while promoting CO selectivity and suppressing HCOOH generation by altering the rate-limiting step toward a high thermodynamic barrier for forming HCOO*. Moreover, the pore-constriction mechanism restricts the bimetallic particles to nanosized dimensions with abundant Zn-Ag-O heterointerfaces and exposed active sites, meanwhile prohibiting detachment and agglomeration of nanoparticles during CO2RR for enhanced stability. The designed catalysts realize 60.9% energy efficiency and 94.1 ± 4.0% Faradaic efficiency toward CO, together with a remarkable stability over 6 days. Beyond providing a high-performance CO2RR electrocatalyst, this work presents a promising catalyst-design strategy for efficient energy conversion.

13.
Angew Chem Int Ed Engl ; 59(31): 12860-12867, 2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32379944

RESUMO

Simultaneously improving energy efficiency (EE) and material stability in electrochemical CO2 conversion remains an unsolved challenge. Among a series of ternary Sn-Ti-O electrocatalysts, 3D ordered mesoporous (3DOM) Sn0.3 Ti0.7 O2 achieves a trade-off between active-site exposure and structural stability, demonstrating up to 71.5 % half-cell EE over 200 hours, and a 94.5 % Faradaic efficiency for CO at an overpotential as low as 430 mV. DFT and X-ray absorption fine structure analyses reveal an electron density reconfiguration in the Sn-Ti-O system. A downshift of the orbital band center of Sn and a charge depletion of Ti collectively facilitate the dissociative adsorption of the desired intermediate COOH* for CO formation. It is also beneficial in maintaining a local alkaline environment to suppress H2 and formate formation, and in stabilizing oxygen atoms to prolong durability. These findings provide a new strategy in materials design for efficient CO2 conversion and beyond.

14.
Small ; 15(44): e1903610, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31512394

RESUMO

Flexible Zn-air batteries have recently emerged as one of the key energy storage systems of wearable/portable electronic devices, drawing enormous attention due to the high theoretical energy density, flat working voltage, low cost, and excellent safety. However, the majority of the previously reported flexible Zn-air batteries encounter problems such as sluggish oxygen reaction kinetics, inferior long-term durability, and poor flexibility induced by the rigid nature of the air cathode, all of which severely hinder their practical applications. Herein, a defect-enriched nitrogen doped-graphene quantum dots (N-GQDs) engineered 3D NiCo2 S4 nanoarray is developed by a facile chemical sulfuration and subsequent electrophoretic deposition process. The as-fabricated N-GQDs/NiCo2 S4 nanoarray grown on carbon cloth as a flexible air cathode exhibits superior electrocatalytic activities toward both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), outstanding cycle stability (200 h at 20 mA cm-2 ), and excellent mechanical flexibility (without observable decay under various bending angles). These impressive enhancements in electrocatalytic performance are mainly attributed to bifunctional active sites within the N-GQDs/NiCo2 S4 catalyst and synergistic coupling effects between N-GQDs and NiCo2 S4 . Density functional theory analysis further reveals that stronger OOH* dissociation adsorption at the interface between N-GQDs and NiCo2 S4 lowers the overpotential of both ORR and OER.

15.
Acta Biomater ; 55: 420-433, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28391053

RESUMO

Peritoneal adhesion is very common after abdominal and pelvic surgery, which leads to a variety of severe complications. Although numerous pharmacological treatments and barrier-based devices have been investigated to minimize or prevent postoperative adhesion, the clinical efficacy is not very encouraging. In this work, a biodegradable and thermoreversible galactose modified xyloglucan (mXG) hydrogel was developed and the efficacy of mXG hydrogel in preventing postoperative peritoneal adhesion was investigated. The 4% (w/v) mXG solution was a free flowing sol at low temperature, but could rapidly convert into a physical hydrogel at body temperature without any extra additives or chemical reactions. In vitro cell tests showed that mXG hydrogel was non-toxic and could effectively resist the adhesion of fibroblasts. Moreover, in vitro and in vivo degradation experiments exhibited that mXG hydrogel was degradable and biocompatible. Finally, the rat model of sidewall defect-cecum abrasion was employed to evaluate the anti-adhesion efficacy of the mXG hydrogel. The results demonstrated that mXG hydrogel could effectively prevent postoperative peritoneal adhesion without side effects. The combination of suitable gel temperature, appropriate biodegradation period, and excellent postoperative anti-adhesion efficacy make mXG hydrogel a promising candidate for the prevention of postsurgical peritoneal adhesion. STATEMENT OF SIGNIFICANCE: Despite numerous drugs or barrier-based devices have been developed to prevent postoperative adhesion, few solutions have proven to be uniformly effective in subsequent clinical trials. In the present study, we developed a biodegradable and thermoreversible galactose modified xyloglucan (mXG) hydrogel by green enzymatic reaction without using any organic reagents. The developed physical mXG hydrogel not only showed excellent injectability, appropriate gelation time and temperature, but also exhibited excellent biocompatibility and biodegradability both in vitro and in vivo. In addition, mXG hydrogel was easy to handle and could effectively prevent postoperative adhesion without side effects in a rat model of sidewall defect-bowel abrasion. Our study provide a safe and effective postoperative anti-adhesion material which may have potential applications in clinical practice.


Assuntos
Implantes Absorvíveis , Glucanos , Hidrogéis , Aderências Teciduais/prevenção & controle , Xilanos , Animais , Linhagem Celular , Glucanos/química , Glucanos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Camundongos , Ratos Sprague-Dawley , Aderências Teciduais/metabolismo , Aderências Teciduais/patologia , Xilanos/química , Xilanos/farmacologia
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