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1.
Adv Mater ; : e2403583, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743929

RESUMO

2D Janus Transition Metal Dichalcogenides (TMDs) have attracted much interest due to their exciting quantum properties arising from their unique two-faced structure, broken-mirror symmetry, and consequent colossal polarization field within the monolayer. While efforts are made to achieve high-quality Janus monolayers, the existing methods rely on highly energetic processes that introduce unwanted grain-boundary and point defects with still unexplored effects on the material's structural and excitonic properties Through high-resolution scanning transmission electron microscopy (HRSTEM), density functional theory (DFT), and optical spectroscopy measurements; this work introduces the most encountered and energetically stable point defects. It establishes their impact on the material's optical properties. HRSTEM studies show that the most energetically stable point defects are single (VS and VSe) and double chalcogen vacancy (VS -VSe), interstitial defects (Mi), and metal impurities (MW) and establish their structural characteristics. DFT further establishes their formation energies and related localized bands within the forbidden band. Cryogenic excitonic studies on h-BN-encapsulated Janus monolayers offer a clear correlation between these structural defects and observed emission features, which closely align with the results of the theory. The overall results introduce the defect genome of Janus TMDs as an essential guideline for assessing their structural quality and device properties.

2.
Ear Hear ; 45(3): 658-665, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38178304

RESUMO

OBJECTIVES: Otitis media is one of the most important causes of hearing loss at an early age. Effective vaccination with the routine 7-valent pneumococcal conjugate vaccine (PCV-7) was introduced in 2000. It has been gradually replaced by the pneumococcal nontypeable Haemophilus influenzae protein D conjugate vaccine or the higher-valent 13-valent PCV (PCV-13) since 2010. Data on the change in otitis media burden in recent years are sparse at the global, regional, and national levels. DESIGN: The Global Burden of Disease 2019 study was used to evaluate the prevalence, incidence, mortality, disability-adjusted life year (DALY) rates, and the average annual percentage changes (AAPCs) in otitis media in geographic populations worldwide from 1990 to 2019. These global trends were further analyzed by subgroup (age, sex, and sociodemographic index [SDI]). RESULTS: Globally, the all-age rate of prevalence (AAPC = -0.7, 95% confidence interval [CI] = -0.7 to -0.8), DALYs (AAPC = -1.0, 95% CI = -1.1 to -1.0), and mortality (AAPC = -6.8, 95% CI = -7.3 to -6.4) from otitis media decreased constantly between 1990 and 2019. The all-age rate of incidence decreased sharply between 2000 and 2009 with an AAPC of -1.2 (95% CI = -1.4 to -0.9) and continued the downward trend between 2010 and 2019 (AAPC = -0.2, 95% CI = -0.3 to -0.1). In 2019, children aged 1 to 4 years old had the highest incidence at 29,127.3 per 100,000 population, while young adults under 30 years old accounted for 91.3% of the incident cases. Individuals living in middle-SDI countries had the largest increase in the incidence of otitis media, with an AAPC of 0.3 (95% CI = 0.3 to 0.3) between 1990 and 2019. The incidence and DALYs from otitis media decreased with increasing SDI. Regionally, the largest increase in incidence was observed in high-income Asia Pacific, Eastern Europe, and Western Sub-Saharan Africa between 1990 and 2019. Nationally, the largest increase in the incidence of otitis media was observed in the Republic of Korea, with an AAPC of 0.8 (95% CI = 0.6 to 1.1) in the same time period. CONCLUSIONS: There have been successful previous endeavors to reduce DALYs and mortality attributed to otitis media on a global scale. The worldwide incidence of otitis media experienced a sharp decline following the introduction of PCV-7 in 2000, and this downward trend persisted in subsequent years with the adoption of PCV-13/pneumococcal nontypeable Haemophilus influenzae protein D conjugate vaccine. Continual epidemiological surveillance of otitis media's global trends, pathogen distribution, and resistance patterns remains imperative.


Assuntos
Otite Média , Criança , Adulto Jovem , Humanos , Lactente , Pré-Escolar , Adulto , Vacinas Conjugadas , Otite Média/epidemiologia , Incidência , Pesquisa , República da Coreia , Anos de Vida Ajustados por Qualidade de Vida
3.
Proc Natl Acad Sci U S A ; 120(52): e2309786120, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38109550

RESUMO

Many sub-Neptune exoplanets have been believed to be composed of a thick hydrogen-dominated atmosphere and a high-temperature heavier-element-dominant core. From an assumption that there is no chemical reaction between hydrogen and silicates/metals at the atmosphere-interior boundary, the cores of sub-Neptunes have been modeled with molten silicates and metals (magma) in previous studies. In large sub-Neptunes, pressure at the atmosphere-magma boundary can reach tens of gigapascals where hydrogen is a dense liquid. A recent experiment showed that hydrogen can induce the reduction of Fe[Formula: see text] in (Mg,Fe)O to Fe[Formula: see text] metal at the pressure-temperature conditions relevant to the atmosphere-interior boundary. However, it is unclear whether Mg, one of the abundant heavy elements in the planetary interiors, remains oxidized or can be reduced by H. Our experiments in the laser-heated diamond-anvil cell found that heating of MgO + Fe to 3,500 to 4,900 K (close to or above their melting temperatures) in an H medium leads to the formation of Mg[Formula: see text]FeH[Formula: see text] and H[Formula: see text]O at 8 to 13 GPa. At 26 to 29 GPa, the behavior of the system changes, and Mg-H in an H fluid and H[Formula: see text]O were detected with separate FeH[Formula: see text]. The observations indicate the dissociation of the Mg-O bond by H and subsequent production of hydride and water. Therefore, the atmosphere-magma interaction can lead to a fundamentally different mineralogy for sub-Neptune exoplanets compared with rocky planets. The change in the chemical reaction at the higher pressures can also affect the size demographics (i.e., "radius cliff") and the atmosphere chemistry of sub-Neptune exoplanets.

4.
Nat Commun ; 14(1): 7665, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996427

RESUMO

Reversible lattice oxygen redox reactions offer the potential to enhance energy density and lower battery cathode costs. However, their widespread adoption faces obstacles like substantial voltage hysteresis and poor stability. The current research addresses these challenges by achieving a non-hysteresis, long-term stable oxygen redox reaction in the P3-type Na2/3Cu1/3Mn2/3O2. Here we show this is accomplished by forming spin singlet states during charge and discharge. Detailed analysis, including in-situ X-ray diffraction, shows highly reversible structural changes during cycling. In addition, local CuO6 Jahn-Teller distortions persist throughout, with dynamic Cu-O bond length variations. In-situ hard X-ray absorption and ex-situ soft X-ray absorption study, along with density function theory calculations, reveal two distinct charge compensation mechanisms at approximately 3.66 V and 3.99 V plateaus. Notably, we observe a Zhang-Rice-like singlet state during 3.99 V charging, offering an alternative charge compensation mechanism to stabilize the active oxygen redox reaction.

5.
Microsc Microanal ; 29(Supplement_1): 413-415, 2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37613134
8.
Microsc Microanal ; 29(4): 1307-1314, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37488821

RESUMO

Photonic modes in dielectric nanostructures, e.g., wide gap semiconductor like CeO2 (ceria), have the potential for various applications such as information transmission and sensing technology. To fully understand the properties of such phenomenon at the nanoscale, electron energy-loss spectroscopy (EELS) in a scanning transmission electron microscope was employed to detect and explore photonic modes in well-defined ceria nanocubes. To facilitate the interpretation of the observations, EELS simulations were performed with finite-element methods. The simulations allow the electric and magnetic field distributions associated with different modes to be determined. A simple analytical eigenfunction model was also used to estimate the energy of the photonic modes. In addition, by comparing various spectra taken at different location relative to the cube, the effect of the surrounding environment on the modes could be sensed. This work gives a high-resolution description of the photonic modes' properties in nanostructures, while demonstrating the advantage of EELS in characterizing optical phenomena locally.

9.
Aging (Albany NY) ; 15(13): 6361-6379, 2023 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-37421595

RESUMO

BACKGROUND: Macrophages play an important role in the occurrence and development of atherosclerosis. However, few existing studies have deliberately analyzed the changes in characteristic genes in the process of macrophage phenotype transformation. METHOD: Carotid atherosclerotic plaque single-cell RNA (scRNA) sequencing data were analyzed to define the cells involved and determine their transcriptomic characteristics. KEGG enrichment analysis, CIBERSORT, ESTIMATE, support vector machine (SVM), random forest (RF), and weighted correlation network analysis (WGCNA) were applied to bulk sequencing data. All data were downloaded from Gene Expression Omnibus (GEO). RESULT: Nine cell clusters were identified. M1 macrophages, M2 macrophages, and M2/M1 macrophages were identified as three clusters within the macrophages. According to pseudotime analysis, M2/M1 macrophages and M2 macrophages can be transformed into M1 macrophages. The ROC curve values of the six genes in the test group were statistically significant (AUC (IL1RN): 0.899, 95% CI: 0.764-0.990; AUC (NRP1): 0.817, 95% CI: 0.620-0.971; AUC (TAGLN): 0.846, 95% CI: 0.678-0.971; AUC (SPARCL1): 0.825, 95% CI: 0.620-0.988; AUC (EMP2): 0.808, 95% CI: 0.630-0.947; AUC (ACTA2): 0.784, 95% CI: 0.591-0.938). The atherosclerosis prediction model showed significant statistical significance in both the train group (AUC: 0.909, 95% CI: 0.842-0.967) and the test group (AUC: 0.812, 95% CI: 0.630-0.966). CONCLUSIONS: IL1RNHigh M1, NRP1High M2, ACTA2High M2/M1, EMP2High M1/M1, SPACL1High M2/M1 and TAGLNHigh M2/M1 macrophages play key roles in the occurrence and development of arterial atherosclerosis. These marker genes of macrophage phenotypic transformation can also be used to establish a model to predict the occurrence of atherosclerosis.


Assuntos
Aterosclerose , Placa Aterosclerótica , Humanos , Análise da Expressão Gênica de Célula Única , Aterosclerose/genética , Aterosclerose/metabolismo , Placa Aterosclerótica/genética , Placa Aterosclerótica/metabolismo , Macrófagos/metabolismo , Fenótipo , Glicoproteínas de Membrana/metabolismo
10.
Diabetes Metab Syndr ; 17(6): 102791, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37271078

RESUMO

AIMS: To understanding the net regional, national, and economic effect of global population ageing on diabetes and its trends during 1990 and 2019 worldwide. METHODS: We employed a decomposition method to estimate the impact of population ageing on diabetes-related disability-adjusted life years (DALYs) and total deaths in 204 countries from 1990 to 2019 at the global, regional, and national level. This method separated the net effect of population ageing from population growth and changes in mortality. RESULTS: Globally, population ageing has become the major contributor to diabetes-related deaths since 2013. The increases in diabetes-related deaths attributed to population ageing exceeding the decreases in mortality change. Population ageing produced an additional 0.42 million diabetes-related deaths and 14.95 million DALYs from 1990 to 2019. At the regional level, population ageing is associated with the increases in diabetes-related deaths in 18 out of 22 regions. The highest increase in diabetes-related deaths attributed to population ageing occurred in men in East Asia (136.31%) and women in Central Latin America (118.58%). The proportion of diabetes-related deaths and DALYs attributable to population ageing showed a bell-shaped relationship with sociodemographic index (SDI) and peaked at high-middle-SDI countries. CONCLUSIONS: The decreases in diabetes-related deaths attributed to mortality change exceeded the increases attributed to population ageing between 1990 and 2019 globally and regionally. The diabetes-related deaths in high-middle-SDI countries were most impacted by population ageing.


Assuntos
Diabetes Mellitus , Anos de Vida Ajustados por Deficiência , Masculino , Humanos , Feminino , Anos de Vida Ajustados por Qualidade de Vida , Envelhecimento , Fatores de Risco
11.
Adv Mater ; 35(32): e2302525, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37321653

RESUMO

Facile approaches capable of constructing stable and structurally diverse porous liquids (PLs) that can deliver high-performance applications are a long-standing, captivating, and challenging research area that requires significant attention. Herein, a facile surface deposition strategy is demonstrated to afford diverse type III-PLs possessing ultra-stable dispersion, external structure modification, and enhanced performance in gas storage and transformation by leveraging the expeditious and uniform precipitation of selected metal salts. The Ag(I) species-modified zeolite nanosheets are deployed as the porous host to construct type III-PLs with ionic liquids (ILs) containing bromide anion , leading to stable dispersion driven by the formation of AgBr nanoparticles. The as-afforded type-III PLs display promising performance in CO2 capture/conversion and ethylene/ethane separation. Property and performance of the as-produced PLs can be tuned by the cation structure of the ILs, which can be harnessed to achieve polarity reversal of the porous host via ionic exchange. The surface deposition procedure can be further extended to produce PLs from Ba(II)-functionalized zeolite and ILs containing [SO4 ]2- anion driven by the formation of BaSO4 salts. The as-produced PLs are featured by well-maintained crystallinity of the porous host, good fluidity and stability, enhanced gas uptake capacity, and attractive performance in small gas molecule utilization.

12.
Nat Commun ; 14(1): 2664, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37160890

RESUMO

Single atoms of platinum group metals on CeO2 represent a potential approach to lower precious metal requirements for automobile exhaust treatment catalysts. Here we show the dynamic evolution of two types of single-atom Pt (Pt1) on CeO2, i.e., adsorbed Pt1 in Pt/CeO2 and square planar Pt1 in PtATCeO2, fabricated at 500 °C and by atom-trapping method at 800 °C, respectively. Adsorbed Pt1 in Pt/CeO2 is mobile with the in situ formation of few-atom Pt clusters during CO oxidation, contributing to high reactivity with near-zero reaction order in CO. In contrast, square planar Pt1 in PtATCeO2 is strongly anchored to the support during CO oxidation leading to relatively low reactivity with a positive reaction order in CO. Reduction of both Pt/CeO2 and PtATCeO2 in CO transforms Pt1 to Pt nanoparticles. However, both catalysts retain the memory of their initial Pt1 state after reoxidative treatments, which illustrates the importance of the initial single-atom structure in practical applications.

13.
Small ; 19(26): e2302295, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37194952

RESUMO

Although the electrocatalytic nitrate reduction reaction (NO3 - RR) is an attractive NH3 synthesis route, it suffers from low yield due to the lack of efficient catalysts. Here, this work reports a novel grain boundary (GB)-rich Sn-Cu catalyst, derived from in situ electroreduction of Sn-doped CuO nanoflower, for effectively electrochemical converting NO3 - to NH3 . The optimized Sn1% -Cu electrode achieves a high NH3 yield rate of 1.98 mmol h-1 cm-2 with an industrial-level current density of -425 mA cm-2 at -0.55 V versus a reversible hydrogen electrode (RHE) and a maximum Faradaic efficiency of 98.2% at -0.51 V versus RHE, outperforming the pure Cu electrode. In situ Raman and attenuated total reflection Fourier transform infrared spectroscopies reveal the reaction pathway of NO3 - RR to NH3 by monitoring the adsorption property of reaction intermediates. Density functional theory calculations clarify that the high-density GB active sites and the competitive hydrogen evolution reaction (HER) suppression induced by Sn doping synergistically promote highly active and selective NH3 synthesis from NO3 - RR. This work paves an avenue for efficient NH3 synthesis over Cu catalyst by in situ reconstruction of GB sites with heteroatom doping.

14.
Water Res ; 234: 119801, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36889084

RESUMO

While co-oxidation is widely used to biodegrade halogenated organic pollutants (HOPs), a considerable amount of organic primary substrate is required. Adding organic primary substrates increases the operating cost and also leads to extra carbon dioxide release. In this study, we evaluated a two-stage Reduction and Oxidation Synergistic Platform (ROSP), which integrated catalytic reductive dehalogenation with biological co-oxidation for HOPs removal. The ROSP was a combination of an H2-based membrane catalytic-film reactor (H2-MCfR) and an O2-based membrane biofilm reactor (O2-MBfR). 4-chlorophenol (4-CP) was used as a model HOP to evaluate the performance of ROSP. In the MCfR stage, zero-valent palladium nanoparticles (Pd0NPs) catalyzed reductive hydrodechlorination that converted 4-CP to phenol, with a conversion yield over 92%. In the MBfR stage, the phenol was oxidized and used as a primary substrate that supported the co-oxidation of residual 4-CP. Genomic DNA sequencing revealed that phenol produced from 4-CP reduction enriched bacteria having genes for functional enzymes for phenol biodegradation in the biofilm community. In the ROSP, over 99% of 60 mg/L 4-CP was removed and mineralized during continuous operation: Effluent 4-CP and chemical oxygen demand concentrations were below 0.1 and 3 mg/L, respectively. H2 was the only added electron donor to the ROSP, which means no extra carbon dioxide was produced by primary-substrate oxidation.


Assuntos
Poluentes Ambientais , Nanopartículas Metálicas , Dióxido de Carbono , Paládio , Fenóis , Oxirredução , Fenol
15.
Angew Chem Int Ed Engl ; 62(20): e202214322, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-36696269

RESUMO

The development of facile methodologies to afford robust supported metal nanocatalysts under mild conditions is highly desirable yet challenging, particularly via strong metal-support interactions (SMSI) construction. State-of-the-art approaches capable of generating SMSI encapsulation mainly focus on high temperature annealing in reductive/oxidative atmosphere. Herein, ultra-stable metal nanocatalysts based on SMSI construction were produced by leveraging the instantaneous high-energy input from ultrasonication under ambient conditions in H2 O, which could rapidly afford abundant active intermediates, Ti3+ ions, and oxygen vacancies within the scaffolds to induce the SMSI overlayer formation. The encapsulation degree could be tuned and controlled via the reducibility of the solvents and the ultrasonication parameters. This facile and efficient approach could be further extended to diverse metal oxide supports and noble metal NPs leading to enhanced performance in hydrogenation reactions and CO2 conversion.

16.
Environ Sci Technol ; 57(1): 666-673, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36445010

RESUMO

Ammunition wastewater contains toxic nitrated explosives like RDX and oxyanions like nitrate and perchlorate. Its treatment is challenged by low efficiency due to contaminant recalcitrance and high cost due to multiple processes needed for separately removing different contaminant types. This paper reports a H2-based low-energy strategy featuring the treatment of explosives via catalytic denitration followed by microbial mineralization coupled with oxyanion reduction. After a nitrate- and perchlorate-reducing biofilm incapable of RDX biodegradation was coated with palladium nanoparticles (Pd0NPs), RDX was rapidly denitrated with a specific catalytic activity of 8.7 gcat-1 min-1, while biological reductions of nitrate and perchlorate remained efficient. In the subsequent 30-day continuous test, >99% of RDX, nitrate, and perchlorate were coremoved, and their effluent concentrations were below their respective regulation levels. Detected intermediates and shallow metagenome analysis suggest that the intermediates after Pd-catalytic denitration of RDX ultimately were enzymatically utilized by the nitrate- and perchlorate-reducing bacteria as additional electron donor sources.


Assuntos
Substâncias Explosivas , Nanopartículas Metálicas , Poluentes Químicos da Água , Purificação da Água , Substâncias Explosivas/análise , Substâncias Explosivas/metabolismo , Percloratos/análise , Percloratos/metabolismo , Nitratos/análise , Nitratos/metabolismo , Poluentes Químicos da Água/análise , Paládio/análise , Reatores Biológicos/microbiologia
17.
Environ Sci Technol ; 56(24): 18030-18040, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36383359

RESUMO

More food production required to feed humans will require intensive use of herbicides to protect against weeds. The widespread application and persistence of herbicides pose environmental risks for nontarget species. Elemental-palladium nanoparticles (Pd0NPs) are known to catalyze reductive dehalogenation of halogenated organic pollutants. In this study, the reductive conversion of 2,4-dichlorophenoxyacetic acid (2,4-D) was evaluated in a H2-based membrane catalyst-film reactor (H2-MCfR), in which Pd0NPs were in situ-synthesized as the catalyst film and used to activate H2 on the surface of H2-delivery membranes. Batch kinetic experiments showed that 99% of 2,4-D was removed and converted to phenoxyacetic acid (POA) within 90 min with a Pd0 surface loading of 20 mg Pd/m2, achieving a catalyst specific activity of 6.6 ± 0.5 L/g-Pd-min. Continuous operation of the H2-MCfR loaded with 20 mg Pd/m2 sustained >99% removal of 50 µM 2,4-D for 20 days. A higher Pd0 surface loading, 1030 mg Pd/m2, also enabled hydrosaturation and hydrolysis of POA to cyclohexanone and glycolic acid. Density functional theory identified the reaction mechanisms and pathways, which involved reductive hydrodechlorination, hydrosaturation, and hydrolysis. Molecular electrostatic potential calculations and Fukui indices suggested that reductive dehalogenation could increase the bioavailability of herbicides. Furthermore, three other halogenated herbicides─atrazine, dicamba, and bromoxynil─were reductively dehalogenated in the H2-MCfR. This study documents a promising method for the removal and detoxification of halogenated herbicides in aqueous environments.


Assuntos
Herbicidas , Nanopartículas Metálicas , Humanos , Paládio/metabolismo , Catálise , Ácido 2,4-Diclorofenoxiacético
18.
Sensors (Basel) ; 22(19)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36236759

RESUMO

The fusion of light detection and ranging (LiDAR) and inertial measurement unit (IMU) sensing information can effectively improve the environment modeling and localization accuracy of navigation systems. To realize the spatiotemporal unification of data collected by the IMU and the LiDAR, a two-step spatiotemporal calibration method combining coarse and fine is proposed. The method mainly includes two aspects: (1) Modeling continuous-time trajectories of IMU attitude motion using B-spline basis functions; the motion of the LiDAR is estimated by using the normal distributions transform (NDT) point cloud registration algorithm, taking the Hausdorff distance between the local trajectories as the cost function and combining it with the hand-eye calibration method to solve the initial value of the spatiotemporal relationship between the two sensors' coordinate systems, and then using the measurement data of the IMU to correct the LiDAR distortion. (2) According to the IMU preintegration, and the point, line, and plane features of the lidar point cloud, the corresponding nonlinear optimization objective function is constructed. Combined with the corrected LiDAR data and the initial value of the spatiotemporal calibration of the coordinate systems, the target is optimized under the nonlinear graph optimization framework. The rationality, accuracy, and robustness of the proposed algorithm are verified by simulation analysis and actual test experiments. The results show that the accuracy of the proposed algorithm in the spatial coordinate system relationship calibration was better than 0.08° (3δ) and 5 mm (3δ), respectively, and the time deviation calibration accuracy was better than 0.1 ms and had strong environmental adaptability. This can meet the high-precision calibration requirements of multisensor spatiotemporal parameters of field robot navigation systems.

19.
Adv Sci (Weinh) ; 9(21): e2200454, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35599159

RESUMO

Electrochemical CO2 reduction reaction can be used to produce value-added hydrocarbon fuels and chemicals by coupling with clean electrical energy. However, highly active, selective, and energy-efficient CO2 conversion to multicarbon hydrocarbons, such as C2 H4 , remains challenging because of the lack of efficient catalysts. Herein, an ultrasonication-assisted electrodeposition strategy to synthesize CuO nanosheets for low-overpotential CO2 electroreduction to C2 H4 is reported. A high C2 H4 Faradaic efficiency of 62.5% is achieved over the CuO nanosheets at a small potential of -0.52 V versus a reversible hydrogen electrode, corresponding to a record high half-cell cathodic energy efficiency of 41%. The selectivity toward C2 H4 is maintained for over 60 h of continuous operation. The CuO nanosheets are prone to in situ restructuring during CO2 reduction, forming abundant grain boundaries (GBs). Stable Cu+ /Cu0 interfaces are derived from the low-coordinated Cu atoms in the reconstructed GB regions and act as highly active sites for CO2 reduction at low overpotentials. In situ Raman spectroscopic analysis and density functional theory computation reveal that the Cu+ /Cu0 interfaces offer high *CO surface coverage and lower the activation energy barrier for *CO dimerization, which, in synergy, facilitates CO2 reduction to C2 H4 at low overpotentials.

20.
Front Oncol ; 12: 801940, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35296005

RESUMO

Background and Aims: Barrett's esophagus with low-grade dysplasia (BE-LGD) carries a risk of progression to Barrett's esophagus with high-grade dysplasia (BE-HGD) and esophageal adenocarcinoma (EAC). Radiofrequency ablation (RFA) appears to be a safe and efficacious method to eradicate Barrett's esophagus. However, a confirmed consensus regarding treatment of BE-LGD with RFA vs. endoscopic surveillance is lacking. Therefore, this study aimed to elucidate the efficacy and safety for RFA vs. endoscopic surveillance in decreasing the risk of BE-LGD progression to BE-HGD or EAC. Methods: Relevant studies published before May 1, 2021 were identified by searching relevant medical databases. The primary outcome was the rate of progression BE-LGD to HGD and/or EAC after treatment with RFA and endoscopic surveillance. The secondary outcome was the rate of complete eradication of dysplasia (CE-D) and complete eradication of intestinal metaplasia (CE-IM) after treatment with RFA and endoscopic surveillance. Adverse events were also extracted and evaluated. Results: Three randomized controlled trials were eligible for analysis. The pooled estimate of rate of neoplastic progression of BE-LGD to HGD or EAC was much lower in the RFA group than the endoscopic surveillance group (RR, 0.25; 95% CI, 0.07-0.93; P = 0.04), with moderate heterogeneity (I2 = 55%). Subgroup analysis based on progression grade was performed. The pooled rate of progression of BE-LGD to HGD was much lower in the RFA group than the endoscopic surveillance group (RR, 0.25; 95% CI, 0.07-0.71; P = 0.01), with low heterogeneity (I2 = 15%). Although the pooled risk of progression of BE-LGD to EAC was slightly lower in the RFA group than the endoscopic surveillance group (RR, 0.56; 95% CI, 0.05-6.76), the result was not statistically significant (P = 0.65). RFA also was associated a higher rate of CE-D and CE-IM both at the end of endoscopic treatment and during follow-up. However, the rate of adverse events was slightly higher after RFA treatment. Conclusion: RFA decreases the risk of BE-LGD progression to BE-HGD. However, given the uncertain course of LGD and the potential for esophageal stricture after RFA, treatment options should be fully considered and weighed. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021266128, identifier PROSPERO (CRD42021266128).

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