Boosting Visible-Light Photocatalytic Activity of BiOCl Nanosheets via Synergetic Effect of Oxygen Vacancy Engineering and Graphene Quantum Dots-Sensitization.

In recent years, oxygen vacancy (VO) engineering has become a research hotspot in the field of photocatalysis. Herein, an efficient GQDs/BiOCl-VO heterojunction photocatalyst was fabricated by loading graphene quantum dots (GQDs) onto BiOCl nanosheets containing oxygen vacancies. ESR and XPS characterizations confirmed the formation of oxygen vacancy. Combining experimental analysis and DFT calculations, it was found that oxygen vacancy promoted the chemical adsorption of O2, while GQDs accelerated electron transfer. Benefiting from the synergistic effect of oxygen vacancy, GQDs, and dye sensitization, the as-prepared GQDs/BiOCl-VO sample exhibited improved efficiency for RhB degradation under visible-light irradiation. A 2 wt% GQDs/BiOCl-VO composite effectively degraded 98% of RhB within 20 min. The main active species were proven to be hole (h+) and superoxide radical (·O2-) via ESR analysis and radical trapping experiments. This study provided new insights into the effective removal of organic pollutants from water by combining defect engineering and quantum dot doping techniques in heterojunction catalysts.

Association between dietary vitamin C and abdominal aortic calcification among the US adults.

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of mortality, and vascular calcification has been highly correlated with CVD events. Abdominal aortic calcification (AAC) has been shown to predict subclinical CVD and incident CVD events. However, the relationship between vitamin C and abdominal aortic calcification remains unclear. OBJECTIVE: To investigate the relationship of dietary vitamin C with AAC among the adult population in the US. METHODS: The National Health and Nutrition Examination Survey (NHANES) 2013-2014 provided the data for the cross-sectional study. 2297 subjects (1089 males) were included in the study. Two scoring systems, AAC 24-point scale (Kauppila) and AAC 8-point scale (Schousboe), were used for the measurement of AAC score. Dietary vitamin C intake was calculated as the average of two rounds of 24-h interview recall data and classified in tertiles for analysis. We applied weighted multiple regression analyses to assess the relationship of dietary vitamin C with AAC score and the risk of having AAC. To ensure the robustness of the findings, subgroup and sensitivity analyses were performed. Additionally, smooth curve fittings, using generalized additive models (GAM) were employed to visualize potential nonlinear relationships. Furthermore, an exploratory analysis on the relationship of vitamin C supplements with AAC was also conducted. RESULTS: The results showed that higher dietary vitamin C intake was related to a reduction in AAC score (AAC-24: ß = -0.338, 95% confidence interval [CI] -0.565, -0.111, P = 0.004; AAC-8: ß = -0.132, 95%CI -0.217, -0.047, P = 0.002), and lower risk of AAC (odds ratio [OR] = 0.807, 95%CI 0.659, 0.989, P = 0.038). However, the relationship of vitamin C supplements with AAC was not identified. CONCLUSIONS: The study revealed that higher intake of dietary vitamin C rather than vitamin C supplements was related to reduced AAC score and lower risk of AAC, indicating that diets rich in vitamin C are recommended due to its potential benefits for protecting against vascular calcification and CVD among the adult population in the US.

Site-Resolved Cu2 O Catalysis in the Oxidation of CO.

The identification of the contribution of different surface sites to the catalytic activity of a catalyst nanoparticle is one of the most challenging issues in the fundamental studies of heterogeneous catalysis. We herein demonstrate an effective strategy of using a series of uniform cubic Cu2 O nanocrystals with different sizes to identify the intrinsic activity and contributions of face and edge sites in the catalysis of CO oxidation by a combination of reaction kinetics analysis and DFT calculations. Cu2 O nanocrystals undergo in situ surface oxidation forming CuO thin films during CO oxidation. As the average size of the cubic Cu2 O nanocrystals decreases from 1029 nm to 34 nm, the dominant active sites contributing to the catalytic activity switch from face sites to edge sites. These results reveal the interplay between the intrinsic catalytic activity and the density of individual types of surface sites on a catalyst nanoparticle in determining their contributions to the catalytic activity.

TiO2 /Cu2 O Core/Ultrathin Shell Nanorods as Efficient and Stable Photocatalysts for Water Reduction.

P-type Cu2 O has been long considered as an attractive photocatalyst for photocatalytic water reduction, but few successful examples has been reported. Here, we report the synthesis of TiO2 (core)/Cu2 O (ultrathin film shell) nanorods by a redox reaction between Cu(2+) and in-situ generated Ti(3+) when Cu(2+) -exchanged H-titanate nanotubes are calcined in air. Owing to the strong TiO2 -Cu2 O interfacial interaction, TiO2 (core)/Cu2 O (ultrathin film shell) nanorods are highly active and stable in photocatalytic water reduction. The TiO2 core and Cu2 O ultrathin film shell respectively act as the photosensitizer and cocatalyst, and both the photoexcited electrons in the conduction band and the holes in the valence band of TiO2 respectively transfer to the conduction band and valence band of the Cu2 O ultrathin film shell. Our results unambiguously show that Cu2 O itself can act as the highly active and stable cocatalyst for photocatalytic water reduction.

The associations between dietary flavonoid intake and hyperlipidemia: data from the national health and nutrition examination survey 2007-2010 and 2017-2018.

Background: Hyperlipidemia is a worldwide health problem and a significant risk factor for cardiovascular diseases; therefore, it imposes a heavy burden on society and healthcare. It has been reported that flavonoids can increase energy expenditure and fat oxidation, be anti-inflammatory, and reduce lipid factor levels, which may reduce the risk of hyperlipidemia. However, the relationship between the prevalence of hyperlipidemia and dietary flavonoid intake in the population remains unclear. Methods: This study included 8,940 adults from the 2007-2010 and 2017-2018 National Health and Nutrition Examination Surveys (NHANES). The relationship between dietary flavonoid intake and the prevalence of hyperlipidemia was analyzed using weighted logistic regression and weighted restricted cubic spline. Results: We found an inverse relationship between subtotal catechins intake and hyperlipidemia prevalence in the third quartile [0.74 (0.56, 0.98), p = 0.04] compared with the first quartile. The prevalence of hyperlipidemia and total flavan-3-ol intake in the third quartile were inversely correlated [0.76 (0.59, 0.98), p = 0.03]. Total anthocyanin intake was inversely related to the prevalence of hyperlipidemia in the third quartile [0.77 (0.62, 0.95), p = 0.02] and the fourth quartile [0.77 (0.60, 0.98), p = 0.04]. The prevalence of hyperlipidemia was negatively correlated with total flavonols intake in the fourth quartile [0.75 (0.60, 0.94), p = 0.02]. Using restricted cubic splines analysis, we found that subtotal catechins intake and total flavan-3-ol intake had a nonlinear relationship with the prevalence of hyperlipidemia. Conclusion: Our study may provide preliminary research evidence for personalizing improved dietary habits to reduce the prevalence of hyperlipidemia.

Remnant cholesterol associates with hypertension beyond low-density lipoprotein cholesterol among the general US adult population.

Background: Previous findings have indicated that elevated low-density lipoprotein cholesterol (LDL-C) and remnant cholesterol (RC) are associated with hypertension. We aim to explore whether higher RC levels may be associated with hypertension beyond LDL-C in the general US adult population. Methods: This study included 10,842 adults from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. Weighted multivariable logistic regression models were used to estimate the odds ratios (ORs) of hypertension for LDL-C and RC. We also performed analyses examining the association between hypertension and LDL-C vs. RC concordant/discordant groups. Results: A total of 4,963 (41.54%, weighted) individuals had hypertension. The weighted median levels were LDL-C: 118mg/dL, RC: 20mg/dL. At lower LDL-C clinical cut-point, the proportion of discordantly high RC dramatically increased. After multivariable adjustment, log RC was associated with higher prevalence of hypertension [OR 2.54, 95% confidence interval (CI) 2.17-2.99]. Participants with the highest tertile of RC were more likely to have hypertension (OR 2.18; 95% CI 1.89-2.52) compared with those with the lowest tertile of RC. This association remained marked after including body mass index (BMI), LDL-C, high-density lipoprotein cholesterol (HDL-C) or triglycerides. The association between LDL-C and hypertension was absent after adjusting for BMI, RC or triglycerides. Compared with low LDL-C/low RC group, the discordant low LDL-C/high RC group was associated with hypertension (OR 2.04; 95% CI 1.72-2.42), whereas the high LDL-C/low RC group was not, regardless of BMI, HDL-C or triglycerides. Similar results were observed when examining discordance among different clinical cut-points, except for the cut-point of LDL-C 70 mg/dL and RC 13 mg/dL. To better understand the association, we performed an additional analysis, which showed that among participants with apolipoprotein B < median (92mg/dL), those with discordant RC ≥ median (20mg/dL) had significantly higher odds of having hypertension (OR 1.73; 95% CI 1.38-2.17). Conclusion: RC was associated with hypertension beyond LDL-C in the general US adult population. This association went beyond increased triglycerides levels, and lipoproteins other than apoB may be involved.

Triglyceride-glucose index and the risk of stroke in American adults: findings from the atherosclerosis risk in communities study.

OBJECTIVES: The associations between the triglyceride-glucose (TyG) index with subsequent stroke in American adults are unknown. The aim of this study was to determine the associations between baseline and trajectories of TyG index with subsequent stroke in American adults. METHODS: A total of 10,132 participants free of a history of stroke at baseline were included. We quantified the association of baseline and trajectories of TyG index with incident total stroke, ischemic stroke and intracerebral hemorrhage using Cox regression, restricted cubic splines and logistic regression analysis. RESULTS: There were 909 incident stroke cases over a median follow-up of 26.6 years. After adjustment for potential confounders, each unit increase in the TyG index was associated with a 32.1% higher risk of incident stroke. Compared with participants in the lowest quartile of the baseline TyG index, those in the highest quartile had a greater risk of incident stroke [HR (95% CI) 1.254 (1.014-1.552)]. Restricted cubic splines showed that the risk of stroke increased in participants with a higher TyG index, especially when the TyG index was > 8.6. Results were similar for incident ischemic stroke. Compared with participants in the lowest quartile of the baseline TyG index, those in the second quartile had a lower risk of intracerebral hemorrhage [HR (95% CI) 0.494 (0.262-0.931)]. Five discrete trajectories with stable TyG indexes at various levels at follow-up visits were identified, and parallel results were observed for the associations of trajectories of TyG index with outcomes. CONCLUSIONS: The TyG index independently predict stroke progression.

Efficacy and Safety of Oral Anticoagulants in Older Adult Patients With Atrial Fibrillation: Pairwise and Network Meta-Analyses.

OBJECTIVE: To evaluate the efficacy and safety of oral anticoagulants for older adult patients with atrial fibrillation (AF). DESIGN: Pairwise and network meta-analyses. SETTING AND PARTICIPANTS: Patients with AF aged ≥75 years. METHODS: PubMed, Embase, and the Cochrane library were searched for published randomized controlled trials and adjusted observational studies evaluating the use of a non-vitamin K antagonist oral anticoagulants (NOACs), vitamin K antagonist, or antiplatelet drug for the prevention of stroke. The primary efficacy and safety outcomes were the composite of stroke and systemic embolism (SSE) and major bleedings. RESULTS: This study included 38 studies enrolling 1,022,908 older adult patients with AF. Results from pairwise meta-analyses showed that NOACs were superior to warfarin for all outcomes, except that dabigatran increased the risk of gastrointestinal (GI) bleedings. Aspirin was associated with a higher risk of SSE and ischemic stroke than warfarin or NOACs. Results of network meta-analyses indicated that apixaban significantly reduced the risk of SSE, major bleedings, and GI bleedings than warfarin, rivaroxaban, and dabigatran. Apixaban, edoxaban, rivaroxaban, and dabigatran reduced the risk of ischemic stroke and intracranial bleeding compared to warfarin. Dabigatran showed lower risk of all-cause mortality than warfarin and of intracranial bleeding than rivaroxaban. CONCLUSIONS AND IMPLICATIONS: NOACs are of at least equal efficacy, or even superior to warfarin. The safety profile of individual NOAC agents was significantly different, as apixaban performs better than the other oral anticoagulants in reducing major bleeding and GI bleeding, whereas dabigatran increased the risk of GI bleeding.

Qing-Xin-Jie-Yu Granule inhibits ferroptosis and stabilizes atherosclerotic plaques by regulating the GPX4/xCT signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Qing-Xin-Jie-Yu Granule (QXJYG) is an integrated traditional Chinese medicine formula used to treat atherosclerotic (AS) cardiovascular diseases. A randomized controlled trial found that QXJYG reduced cardiovascular events and experiments also verified that QXJYG attenuated AS by remodeling the intestinal flora. AIM OF THE STUDY: To determine whether QXJYG would attenuate AS and plaque vulnerability by regulating ferroptosis in high-fat diet-induced atherosclerotic ApoE-/- mice and to investigate the effects of QXJYG on macrophage ferroptosis in RAS-selective lethal 3 (RSL3)-induced J744A.1 cells. METHODS: AS models in ApoE-/- mice and RSL3-induced ferroptosis in J744A.1 cells were established to measure the protective and anti-ferroptotic effects of QXJYG in vivo and in vitro. The glutathione peroxidase 4 (GPX4)/cystine glutamate reverse transporter (xCT) signal pathway was examined by immunohistochemistry and western blotting. RESULTS: QXJYG attenuated AS progression and plaque vulnerability. Characteristic morphological changes of ferroptosis in the QXJYG-treated animals were rare. Total iron was significantly lower in the QXJYG group than in the model group (P < 0.05); QXJYG suppressed the lipid peroxidation (LPO) levels (malondialdehyde), enhanced the antioxidant capacity (superoxide dismutase and glutathione), and reduced inflammatory factors (interleukin [IL]-6, IL-1ß, tumor necrosis factor-α) associated with ferroptosis. Expression of GPX4/xCT in aorta tissues was remarkably increased in the QXJYG group. QXJYG inhibited ferroptosis in J744A.1 macrophages disturbed using RSL3. The Fe2+, LPO, and reactive oxygen species levels were lower in the QXJYG group than in the RSL3 group (P < 0.05). The QXJYG group showed higher expression of the GPX4/xCT signal pathway. CONCLUSION: QXJYG inhibits ferroptosis in vulnerable AS plaques partially via the GPX4/xCT signaling pathway.

Association between dietary inflammatory index and atherosclerosis cardiovascular disease in U.S. adults.

Objective: To evaluate the association between dietary inflammatory index (DII) and Atherosclerotic cardiovascular disease (ASCVD) among U.S. adults. Methods: We collected data from National Health and Nutrition Examination Survey (NHANES) between 1999 and 2018. Adults who reported complete information to diagnose ASCVD and calculate DII were included. We used three models to differentially adjust the covariates, including age, sex, race or ethnicity, education level, smoking status, poverty, insurance, body mass index, hyperlipemia, hypertension, and diabetes. Logistic regression was used to estimate the Odds Ratio (OR) and 95% confidence interval (95% CI) for ASCVD grouped by DII deciles. We additionally conducted spline smoothing with the generalized additive model (GAM) and the log-likelihood ratio to examine the non-linear relationship between DII and ASCVD. If exists, the segmented linear regression will be used to detect the cutoff point. The subgroup analyses were stratified by various atherosclerotic cardiovascular diseases (i.e., CHD, angina, heart attack, and stroke) and sex. Results: A total of 48,733 participants (mean age, 47.13 ± 0.19 years) with 51.91% women were enrolled, of which 5,011 were diagnosed with ASCVD. In the crude model, participants in the five highest deciles (D6, 7, 8, 9, and 10) of DII score had a significantly higher risk of having ASCVD compared to those in the first decile. In the fully adjusted model, those in the tenth decile [OR = 1.47, 95% CI = (1.18,1.84)] of DII had a significantly increased risk of ASCVD compared to the first decile. Notably, when DII is above 3, the ASCVD risk increased by 41% for each one increase in DII [OR = 1.41, 95% CI = (1.15,1.73)]. This relationship was more pronounced in females. Conclusion: Our study revealed a positive and non-linearly association between DII and ASCVD in U.S. adults. This relationship was more pronounced in females. The findings provide a reference for future research and diet recommendations.

Molecular oxygen enhances H2O2 utilization for the photocatalytic conversion of methane to liquid-phase oxygenates.

H2O2 is widely used as an oxidant for photocatalytic methane conversion to value-added chemicals over oxide-based photocatalysts under mild conditions, but suffers from low utilization efficiencies. Herein, we report that O2 is an efficient molecular additive to enhance the utilization efficiency of H2O2 by suppressing H2O2 adsorption on oxides and consequent photogenerated holes-mediated H2O2 dissociation into O2. In photocatalytic methane conversion over an anatase TiO2 nanocrystals predominantly enclosed by the {001} facets (denoted as TiO2{001})-C3N4 composite photocatalyst at room temperature and ambient pressure, O2 additive significantly enhances the utilization efficiency of H2O2 up to 93.3%, giving formic acid and liquid-phase oxygenates selectivities respectively of 69.8% and 97% and a formic acid yield of 486 µmolHCOOH·gcatalyst-1·h-1. Efficient charge separation within TiO2{001}-C3N4 heterojunctions, photogenerated holes-mediated activation of CH4 into ·CH3 radicals on TiO2{001} and photogenerated electrons-mediated activation of H2O2 into ·OOH radicals on C3N4, and preferential dissociative adsorption of methanol on TiO2{001} are responsible for the active and selective photocatalytic conversion of methane to formic acid over TiO2{001}-C3N4 composite photocatalyst.

Oxidative Coupling of Methanol with Molecularly Adsorbed Oxygen on Au Surface to Methyl Formate.

Supported Au catalysts efficiently catalyze the oxidative coupling of methanol with O2 to methyl formate, in which the atomic O species (O(a)) formed via O2 dissociation on the Au surface has been considered as the active oxygen species. Herein we report for the first time that the oxidative coupling of methanol can occur facilely with molecularly adsorbed O2 species (O2(a)) on a Au(997) surface at temperatures as low as around 125 K, while that with O(a) occurs at around 175 K. Both experimental and theoretical calculation results demonstrate a novel reaction mechanism of oxidative coupling of CH3OH with O2(a) via a dioxymethylene (H2COO) intermediate, resulting in the production of both HCOOCH3 and HCOOCH3. These results reveal the unique reactivity of molecularly adsorbed O2 species on Au surfaces for low-temperature oxidation reactions.

The active sites of Cu-ZnO catalysts for water gas shift and CO hydrogenation reactions.

Cu-ZnO-Al2O3 catalysts are used as the industrial catalysts for water gas shift (WGS) and CO hydrogenation to methanol reactions. Herein, via a comprehensive experimental and theoretical calculation study of a series of ZnO/Cu nanocrystals inverse catalysts with well-defined Cu structures, we report that the ZnO-Cu catalysts undergo Cu structure-dependent and reaction-sensitive in situ restructuring during WGS and CO hydrogenation reactions under typical reaction conditions, forming the active sites of CuCu(100)-hydroxylated ZnO ensemble and CuCu(611)Zn alloy, respectively. These results provide insights into the active sites of Cu-ZnO catalysts for the WGS and CO hydrogenation reactions and reveal the Cu structural effects, and offer the feasible guideline for optimizing the structures of Cu-ZnO-Al2O3 catalysts.

The most active Cu facet for low-temperature water gas shift reaction.

Identification of the active site is important in developing rational design strategies for solid catalysts but is seriously blocked by their structural complexity. Here, we use uniform Cu nanocrystals synthesized by a morphology-preserved reduction of corresponding uniform Cu2O nanocrystals in order to identify the most active Cu facet for low-temperature water gas shift (WGS) reaction. Cu cubes enclosed with {100} facets are very active in catalyzing the WGS reaction up to 548 K while Cu octahedra enclosed with {111} facets are inactive. The Cu-Cu suboxide (CuxO, x ≥ 10) interface of Cu(100) surface is the active site on which all elementary surface reactions within the catalytic cycle proceed smoothly. However, the formate intermediate was found stable at the Cu-CuxO interface of Cu(111) surface with consequent accumulation and poisoning of the surface at low temperatures. Thereafter, Cu cubes-supported ZnO catalysts are successfully developed with extremely high activity in low-temperature WGS reaction.Nanocrystals display a variety of facets with different catalytic activity. Here the authors identify the most active facet of copper nanocrystals relevant to the low-temperature water gas shift reaction and further design zinc oxide-copper nanocubes with exceptionally high catalytic activity.