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1.
Angew Chem Int Ed Engl ; : e202410979, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38967363

ABSTRACT

Catalytic removal of alkynes is essential in industry for producing polymer-grade alkenes from steam cracking processes. Non-noble Ni-based catalysts hold promise as effective alternatives to industrial Pd-based catalysts but suffer from low activity. Here we report embedding of single-atom Pd onto the NiGa intermetallic surface with replacing Ga atoms via a well-defined synthesis strategy to design Pd1-NiGa catalyst for alkyne semi-hydrogenation. The fabricated Pd1Ni2Ga1 ensemble sites deliver remarkably higher specific mass activity under superb alkene selectivity of >96% than the state-of-the-art catalysts under industry-relevant conditions. Integrated experimental and computational studies reveal that the single-atom Pd located synergizes with the neighbouring Ni sites to facilitate the σ-adsorption of alkyne and dissociation of hydrogen while suppress the alkene adsorption. Such synergistic effects confer the single-atom Pd on the NiGa intermetallic with a Midas touch for alkyne semi-hydrogenation, providing an effective strategy for stimulating low active Ni-based catalysts for other selective hydrogenations in industry.

2.
Nat Commun ; 15(1): 3249, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38627484

ABSTRACT

The development of sustainable and anti-poisoning single-atom catalysts (SACs) is essential for advancing their research from laboratory to industry. Here, we present a proof-of-concept study on the poisoning of Au SACs, and the antidote of Au nanoparticles (NPs), with trace addition shown to reinforce and sustain propylene epoxidation. Multiple characterizations, kinetics investigations, and multiscale simulations reveal that Au SACs display remarkable epoxidation activity at a low propylene coverage, but become poisoned at higher coverages. Interestingly, Au NPs can synergistically cooperate with Au SACs by providing distinct active sites required for H2/O2 and C3H6 activations, as well as hydroperoxyl radical to restore poisoned SACs. The difference in reaction order between C3H6 and H2 (nC3H6-nH2) is identified as the descriptor for establishing the volcano curves, which can be fine-tuned by the intimacy and composition of SACs and NPs to achieve a rate-matching scenario for the formation, transfer, and consumption of hydroperoxyl. Consequently, only trace addition of Au NPs antidote (0.3% ratio of SACs) stimulates significant improvements in propylene oxide formation rate, selectivity, and H2 efficiency compared to SACs alone, offering a 56-fold, 3-fold, and 22-fold increase, respectively, whose performances can be maintained for 150 h.

3.
Eur J Pharmacol ; 971: 176539, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38565342

ABSTRACT

Hypoxic-ischemic brain damage (HIBD) is a cerebral injury resulting from the combination of ischemia and hypoxia in neonatal brain tissue. Presently, there exists no efficacious remedy for HIBD. A mounting body of evidence indicates that dynamic metabolites formed during metabolic procedures assume a vital role in neuronal maturation and recuperation. However, it remains unclear whether any endogenous metabolites are involved in the pathogenesis of HIBD. Here, an untargeted metabolomics analysis was conducted by gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry (GC/LC-MS) in OGD/R (oxygen-glucose deprivation/reoxygenation)-induced HT-22 cells. We observed that ferroptosis signaling plays an essential role in HI-induced neuronal injury. Interestingly, we also found that the differentially expressed metabolite, 2-phosphoglyceric acid, significantly improved the neuronal cell survival of OGD/R HT-22 cells by inhibiting ferroptosis. Moreover, 2-phosphoglyceric acid effectively rescued the cell activity of HT-22 cells treated with the ferroptosis inducer RSL-3. Furthermore, 2-phosphoglyceric acid alleviated cerebral infarction and reduced HIBD-induced neuronal cell loss of the central nervous system in neonatal rats by regulating GPX4 expression. Taken together, we found that 2-phosphoglyceric acid, which was downregulated in HT-22 cells induced by OGD/R, exerted neuronal protective effects on OGD/R-treated HT-22 cells and HIBD-induced neonatal rats by inhibiting hypoxic-ischemic-induced ferroptosis through the regulation of the GPX4/ACSL4 axis.


Subject(s)
Hypoxia-Ischemia, Brain , Rats , Animals , Animals, Newborn , Rats, Sprague-Dawley , Hypoxia-Ischemia, Brain/metabolism , Hypoxia/metabolism , Brain/metabolism
4.
Lipids Health Dis ; 23(1): 123, 2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38678275

ABSTRACT

BACKGROUND: The triglyceride glucose (TyG) index and triglyceride-to-high-density lipoprotein cholesterol (TG/HDL-C) ratio are recognized as simple non-insulin-based insulin resistance indices. Our study aimed to explore the relationship between these two indicators and heart failure (HF) in overweight or obesity individuals without diabetes. METHODS: This cross-sectional study selected 13,473 participants from the National Health and Nutrition Examination Survey (NHANES) 2001-2018 dataset. Weighted multivariable logistic regression and subgroup analysis were employed to evaluate the relationships between TyG index, TG/HDL-C ratio, and HF prevalence, respectively. Additionally, smooth curve fitting was utilized to analyze the dose-response relationships. RESULTS: A total of 13,473 obesity or overweight people without diabetes were included in this study through screening, among whom 291 (2.16%) had comorbid HF. The results of multivariable logistic regression suggested that the highest TyG index (OR = 2.4, 95% CI = 1.4-4.2, p = 0.002) and the highest TG/HDL-C ratio (OR = 1.2, 95% CI = 1.1-1.3, p < 0.001) both increased the prevalence of HF, especially in the non-Hispanic population. Dose-response relationships suggested nonlinear relationships between these two indicators and HF. CONCLUSION: Our study demonstrated that elevated TyG index and TG/HDL-C ratio were closely associated with the prevalence of HF, and both exhibited nonlinear relationships with HF prevalence in overweight/obesity adults without diabetes. Based on these findings, additional prospective studies are needed for further validation.


Subject(s)
Heart Failure , Insulin Resistance , Nutrition Surveys , Obesity , Overweight , Triglycerides , Adult , Aged , Female , Humans , Male , Middle Aged , Blood Glucose/metabolism , Cholesterol, HDL/blood , Cross-Sectional Studies , Heart Failure/epidemiology , Heart Failure/blood , Logistic Models , Obesity/epidemiology , Obesity/blood , Overweight/epidemiology , Overweight/blood , Prevalence , Triglycerides/blood
5.
Cerebrovasc Dis ; 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38228101

ABSTRACT

Observational studies have suggested a possible relationship between gut microbiota (GM) and aneurysm development. However, the nature of this association remains unclear due to the inherent limitations of observational research, such as reverse causation and confounding factors. To address this knowledge deficit, this study aimed to investigate and establish a causal link between GM and aneurysm development.

6.
Angew Chem Int Ed Engl ; 63(1): e202314288, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-37988201

ABSTRACT

Methanol serves as a versatile building-block for various commodity chemicals, and the development of industrially promising strategies for its conversion remains the ultimate goal in methanol chemistry. In this study, we design a dual Cu-Cs catalytic system that enables a one-step direct conversion of methanol and methyl acetate/ethanol into high value-added esters/aldehydes, with customized chain length and saturation by leveraging the proximity and distribution of Cu-Cs sites. Cu-Cs at a millimeter-scale intimacy triggers methanol dehydrogenation and condensation, involving proton transfer, aldol formation, and aldol condensation, to obtain unsaturated esters and aldehydes with selectivities of 76.3 % and 31.1 %, respectively. Cu-Cs at a micrometer-scale intimacy significantly promotes mass transfer of intermediates across catalyst interfaces and their subsequent hydrogenation to saturated esters and aldehydes with selectivities of 67.6 % and 93.1 %, respectively. Conversely, Cu-Cs at a nanometer-scale intimacy alters reaction pathway with a similar energy barrier for the rate-determining step, but blocks the acidic-basic sites and diverts the reaction to byproducts. More importantly, an unprecedented quadruple tandem catalytic production of methyl methacrylate (MMA) is achieved by further tailoring Cu and Cs distribution across the reaction bed in the configuration of Cu-Cs||Cs, outperforming the existing industrial processes and saving at least 15 % of production costs.

7.
Eur J Cardiothorac Surg ; 64(6)2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38078822

ABSTRACT

OBJECTIVES: Chest tube (CT) drainage is a main cause of postoperative pain in lung surgery. Here, we introduced a novel drainage strategy with bi-pigtail catheters (PCs) and conducted a randomized controlled trial to compare with conventional CT drainage after uniportal video-assisted thoracic surgery lung surgery. METHODS: A single-centre, prospective, open-labelled, randomized controlled trial (ChiCTR2000035337) was conducted with a preplanned sample size of 396. The primary outcome was the numerical pain rating scale (NPRS) on the first postoperative day. Secondary outcomes included other indicators of postoperative pain, drainage volume, duration of drainage, postoperative hospital stay, incidence of postoperative complications, CT reinsertion and medical costs. RESULTS: A total number of 396 patients were randomized between August 2020 and January 2021, 387 of whom were included in the final analysis. The baseline and clinical characteristics of the patients were well balanced between 2 groups. The NPRS on the first postoperative day was significantly lower in the PC group than in the CT group (2.40 ± 1.27 vs 3.02 ± 1.39, p < 0.001), as well as the second/third-day NPRS, the incidence of sudden severe pain (9/192, 4.7% vs 34/195, 17.4%, P < 0.001) and pain requiring intervention (19/192, 9.9% vs 46/195, 23.6%, P < 0.001). In addition, the medical cost in the PC group was lower (US$7809 ± 1646 vs US$8205 ± 1815, P = 0.025). Univariable and multivariable analyses revealed that the drainage strategy was the only factor influencing the incidence of pain requiring intervention. CONCLUSIONS: The drainage strategy with bi-PCs in patients undergoing uniportal video-assisted thoracic surgery lung surgery alleviates postoperative pain with adequate safety and efficacy.


Subject(s)
Chest Tubes , Lung Neoplasms , Humans , Chest Tubes/adverse effects , Thoracic Surgery, Video-Assisted/adverse effects , Prospective Studies , Lung Neoplasms/surgery , Pain, Postoperative/etiology , Pain, Postoperative/prevention & control , Pain, Postoperative/surgery , Pneumonectomy/adverse effects , Cardiac Catheters , Drainage/adverse effects , Lung
8.
Clin Exp Hypertens ; 45(1): 2280758, 2023 Dec 31.
Article in English | MEDLINE | ID: mdl-37963203

ABSTRACT

Circular RNAs (circRNAs) regulate the function of vascular smooth muscle cells (VSMCs) in atherosclerosis (AS) progression. We aimed to explore the role of circUSP9X in oxidized low-density lipoprotein (ox-LDL)-induced VSMCs. Cell proliferation was assessed using cell counting kit-8 and EDU assays. Cell migration was evaluated using Transwell and wound healing assays. The interaction between circUSP9X or STIM1 and miR-599 was analyzed using dual-luciferase reporter and RNA pull-down assays. Their levels were examined using quantitative real-time PCR. CircUSP9X and STIM1 expression was increased, whereas miR-599 expression was reduced in the serum of patients with AS and ox-LDL-stimulated VSMCs. Overexpression of circUSP9X facilitated the proliferation and migration of VSMCs induced by ox-LDL. CircUSP9X sponged miR-599, which targeted STIM1. MiR-599 reversed the effects induced by circUSP9X, and STIM1 reversed the effects induced by miR-599. Taken together, CircUSP9X promoted proliferation and migration in ox-LDL-treated VSMCs via the miR-599/STIM1 axis, providing a theoretical basis for the role of circUSP9X/miR-599/STIM1 axis in AS.


Subject(s)
Atherosclerosis , MicroRNAs , Humans , Muscle, Smooth, Vascular , Atherosclerosis/genetics , Cell Proliferation , Lipoproteins, LDL/pharmacology , MicroRNAs/genetics
10.
Open Med (Wars) ; 18(1): 20230755, 2023.
Article in English | MEDLINE | ID: mdl-37426050

ABSTRACT

[This corrects the article DOI: 10.1515/med-2021-0319.].

11.
J Electrocardiol ; 80: 155-161, 2023.
Article in English | MEDLINE | ID: mdl-37422943

ABSTRACT

INTRODUCTION: Past research based on observations has suggested that the gut microbiome (GM) could play a role in developing arrhythmias and conduction blocks. Nonetheless, the nature of this association remains uncertain due to the potential for reverse causation and confounding factors in observational research. The aim of this investigation is to elucidate the causal relationship between GM and the development of arrhythmias as well as conduction blocks. METHODS: This study collected summary statistics regarding GM, arrhythmias, and conduction blocks. Two-sample Mendelian randomization (MR) analysis was carried out employing various methods, with inverse variance weighted being the primary approach, followed by weighted median, simple mode, MR-Egger, and MR-PRESSO. Moreover, the MR findings were corroborated through multiple sensitivity analyses. RESULTS: Among them, for atrial fibrillation and flutter (AF), phylum_Actinobacteria and genus_RuminococcaceaeUCG004 demonstrated a negative correlation, while order_Pasteurellales, family_Pasteurellaceae, and genus_Turicibacter were associated with an increased risk. In the case of paroxysmal tachycardia (PT), genus_Holdemania and genus_Roseburia were found to reduce risk. For atrioventricular block (AVB), order_Bifidobacteriales, family_Bifidobacteriaceae, and genus_Alistipes exhibited a negative correlation, whereas genus_CandidatusSoleaferrea showed a positive correlation. Concerning the left bundle-branch block (LBBB), family_Peptococcaceae appeared to decrease the risk, while genus_Flavonifractor was linked to an increased risk. Lastly, no causative GM was identified in the right bundle-branch block (RBBB) context. CONCLUSION: We have uncovered potential causal links between some GM, arrhythmias, and conduction blocks. This insight may aid in designing microbiome-based interventions for these conditions and their risk factors in future trials. Additionally, it could facilitate the discovery of novel biomarkers for targeted prevention strategies.


Subject(s)
Atrial Fibrillation , Gastrointestinal Microbiome , Humans , Mendelian Randomization Analysis , Electrocardiography , Bundle-Branch Block
12.
Eur J Clin Nutr ; 77(11): 1014-1025, 2023 11.
Article in English | MEDLINE | ID: mdl-37488260

ABSTRACT

The effect of time-restricted eating (TRE) has been summarized in previous studies, but its benefits in combination with calorie restriction (CR) still need to be determined. The present meta-analysis aimed to evaluate the efficacy of TRE with CR on weight loss and cardiometabolic risk. PubMed, Embase, Cochrane Library, and gray literature databases were searched from inception to October 18, 2022, for potential randomized controlled trial (RCT) studies based on predefined inclusion and exclusion criteria. Body weight and other cardiometabolic risk factors were described as weighted mean difference (WMD) with a 95% confidence interval (CI). Eight RCTs involving 579 participants were enrolled in the present analysis. The pooled results showed that TRE with CR reduced the body weight, fat mass, and waist circumference significantly (WMD: -1.40, 95% CI: -1.81 to -1.00, and I2: 0%; WMD: -0.73, 95% CI: -1.39 to -0.07, and I2: 0%; WMD: -1.87, 95% CI: -3.47 to -0.26, and I2: 67.25%, respectively). However, compared with CR alone, TRE plus CR exhibited no significant benefit on the blood pressure, glucose profile, and lipid profile. Subgroup analysis suggested that early TRE is more effective in weight loss (WMD: -1.42, 95% CI: -1.84 to -1.01, and I2: 0%) and improving fat mass (WMD: -1.06, 95% CI: -1.91 to -0.22, and I2: 0%) than delayed or broader TRE when combined with CR. Although the combination of TRE and CR can effectively decrease body weight, fat mass, and waist circumference, the long-term effects, particularly those on cardiometabolic risk in participants with chronic cardiovascular disease and diabetes, remain to be explored.


Subject(s)
Caloric Restriction , Cardiovascular Diseases , Humans , Body Weight , Weight Loss , Cardiovascular Diseases/prevention & control , Blood Pressure
13.
Angew Chem Int Ed Engl ; 62(19): e202301024, 2023 May 02.
Article in English | MEDLINE | ID: mdl-36912609

ABSTRACT

Polyethylene terephthalate (PET) hydrogenolysis can produce benzene, toluene, and xylene (BTX), where the selectivity control is challenging. We report a reaction pathway dictated by the Ru coordination environment by examining the binding geometries of adsorbates on differently coordinated Ru centers and their evolution during PET hydrogenolysis. A BTX yield of 77 % was obtained using a Ru/TiO2 with a Ru coordination number of ca. 5.0 where edge/corner sites are dominant, while more gas and saturated products were formed for Ru/TiO2 containing primarily terrace sites. Density functional theory and isotopic labelling revealed that under-coordinated Ru edge sites favor "upright" adsorption of aromatic adsorbates while well-coordinated Ru sites favor "flat-lying" adsorption, where the former mitigates ring hydrogenation and opening. This study demonstrates that reaction pathways can be directed through controlled reactant/intermediate binding via tuning of the Ru coordination environment for efficient conversion of PET to BTX.

14.
Plant Dis ; 2023 Mar 27.
Article in English | MEDLINE | ID: mdl-36973907

ABSTRACT

Juglans regia L. is commercially important for its edible nuts, which is a major species of walnut trees in Sichuan Province (Luo et al. 2020). In September 2021, brown leaf spot symptoms were observed on roughly 75% of 60 J. regia trees surveyed in an orchard of Chongzhou city (30°40'6''N, 103°40'18''E). Initially, the lesions measuring 2-10 mm were reddish to brown with a yellowish halo, then increased in size and coalesced to cover the whole leaf, eventually resulting in severe defoliation. Six symptomatic leaves from different trees were collected, and a single fungal isolate was obtained from each of the sampled leaves using single-spore isolation (Chomnunti et al. 2014). The isolates were incubated on potato dextrose agar (PDA) with a 12h photoperiod at 25 ℃, and deposited at the Culture Collection of Sichuan Agricultural University. Colonies were identical with black center and reddish-brown periphery, and the diameter reached 2 cm after 7 days. On the host, conidiophores were mostly reduced to conidiogenous cells, with prominent and thickened conidiogenous loci. Conidia were light green to light brown, and curved with a thickened and darked hilum at the base, 0-17 septate, tapering toward the distal end, and measuring 20-120 × 3-5 µm ((x ) ̅= 56 × 4, n = 30). Morphological characteristics fit the description of Ragnhildiana diffusa (Heald & F.A. Wolf) Videira & Crous (Synonym: Sirosporium diffusum (Heald & F. A. Wolf) Deighton) (Poletto et al. 2017). The internal transcribed spacer (ITS) region, the large subunit of the nrDNA (LSU), and RNA polymerase II second largest subunit (rpb2) were amplified by polymerase chain reaction and sequenced with primers ITS5/ITS4 (White et al. 1990), LR0R/LR5 (Vilgalys & Hester 1990), fRPB2-5F/Rpb2-R3 (Liu et al. 1999, Videira et al. 2017), respectively. The nucleotide blast of the two isolates (SICAUCC 22-0077, SICAUCC 22-0078) showed 99.7% and 99.5% (ITS, 472/473 bp, 471/473 bp), 100% (LSU, 725/725 bp, 725/725 bp), 99.8% (rpb2, 866/867 bp, 866/867 bp) identities with the ex-type strain of Ragnhildiana diffusa (CBS 106.14). The phylogenetic tree combined with ITS, LSU, and rpb2 genes and morphological characteristics confirmed the identification as R. diffusa. These sequences of the three gene regions of two isolates were deposited in GenBank with accession numbers ON409525 and ON409526 (ITS), ON409559 and ON409560 (LSU), ON417473 and ON417474 (rpb2), respectively. The isolate SICAUCC 22-0077 was used for pathogenicity test to fulfill Koch's postulates. Three leaves of each walnut seedlings (2-year-old seedlings) were inoculated by placing a mycelium plug onto fresh wounds on the upper leaf surface punctured via a fine needle (0.7 mm in diameter), and three replicate seedlings were inoculated. For the control, a sterile PDA plug was placed on the same number of replicate leaves on the plants. The inoculated and control plants were placed in a growth chamber at 25°C with relative humidity >80% and a 12-h photoperiod. Irregular light to dark brown spots developed on inoculated leaves after twenty days, and no symptoms were observed on controls. The re-isolation and examination of the fungus showed it to be morphologically and phylogenetically identical to the originally isolated pathogen. R. diffusa has been described on J. regia in Mexico (Farr & Rossman 2022). To our knowledge, this is the first report of R. diffusa causing brown leaf spot on J. regia in China. The identification of the pathogen will provide a basis for disease management in walnut planting areas.

15.
Chemosphere ; 327: 138536, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36990356

ABSTRACT

In this work, 3D particle-resolved CFD simulations have been performed to investigate the thermal effects of natural gas production from coke oven gas. The catalyst packing structures with uniform, gradient rise and gradient descent distribution and the operating conditions of pressure, wall temperature, inlet temperature and feed velocity are optimized for reduced hot spot temperature. The simulation results show that compared with packing structures with uniform distribution and gradient descent distribution, the gradient rise distribution could effectively reduce the hot spot temperature without affecting the reactor performance in the reactor with upflow reactants feeding, of which the reactor bed temperature rise is 37 K. Under the conditions with the pressure of 20 bar, wall temperature of 500 K, inlet temperature of 593 K, inlet flow rate of 0.04 m/s, the packing structure with gradient rise distribution exhibits the minimum reactor bed temperature rise of 19 K. By optimizing the catalyst distribution and operation conditions, the hot spot temperature of CO methanation process could be dramatically reduced by 49 K at the sacrifice of slightly reduced CO conversion.


Subject(s)
Coke , Natural Gas , Temperature , Hot Temperature , Computer Simulation
16.
Exp Anim ; 72(1): 77-87, 2023 Feb 21.
Article in English | MEDLINE | ID: mdl-36184484

ABSTRACT

Carbon monoxide (CO) has been reported to exhibit a therapeutic effect in lipopolysaccharide (LPS)-induced acute lung injury (ALI). However, the precise mechanism by which CO confers protection against ALI remains unclear. Pyroptosis has been recently proposed to play an essential role in the initiation and progression of ALI. Thus, we investigated whether pyroptosis is involved in the protection of CO against ALI and its underlying mechanism. First, an LPS-induced ALI mouse model was established. To determine the role of pyroptosis, we evaluated histological changes and the expression levels of cleaved caspase-11, N-gasdermin D (GSDMD), and IL-1ß in lung tissues, which are the indicators of pyroptosis. Inhalation of CO exhibited protective effects on LPS-induced ALI by decreasing TNF-α and IL-10 expression and ameliorating pathological changes in lung tissue. In vitro, CO significantly reduced the expression of cleaved caspase-11, N-GSDMD, IL-1ß, and IL-18. In addition, it increased nuclear factor E2-related factor 2 (NRF-2) expression in a time-dependent manner in RAW 264.7 cells and decreased N-GSDMD expression. The expression of cleaved GSDMD and release of LDH were increased after treatment with a specific NRF-2 inhibitor, ML385, indicating that NRF-2 mediates the inhibition of pyroptosis by CO. Taken together, these results demonstrated that CO upregulated NRF-2 to inhibit pyroptosis and subsequently ameliorated LPS-induced ALI.


Subject(s)
Acute Lung Injury , Macrophages, Alveolar , Mice , Animals , Macrophages, Alveolar/metabolism , Macrophages, Alveolar/pathology , Lipopolysaccharides/adverse effects , Carbon Monoxide/adverse effects , Pyroptosis , Acute Lung Injury/chemically induced , Caspases/adverse effects
17.
Acc Chem Res ; 55(22): 3230-3241, 2022 11 15.
Article in English | MEDLINE | ID: mdl-36321554

ABSTRACT

Heterogeneous catalysis is the workhorse of the chemical industry, and a heterogeneous catalyst possesses numerous active sites working together to drive the conversion of reactants to desirable products. Over the decades, much focus has been placed on identifying the factors affecting the active sites to gain deep insights into the structure-performance relationship, which in turn guides the design and preparation of more active, selective, and stable catalysts. However, the molecular-level interplay between active sites and catalytic function still remains qualitative or semiquantitative, ascribed to the difficulty and uncertainty in elucidating the nature of active sites for its controllable manipulation. Hence, bridging the microscopic properties of active sites and the macroscopic catalytic performance, that is, microscopic-to-macroscopic transition, to afford a quantitative description is intriguing yet challenging, and progress toward this promises to revolutionize catalyst design and preparation.In this Account, we propose mesokinetics modeling, for the first time enabling a quantitative description of active site characteristics and the related mechanistic information, as a versatile tool to guide rational catalyst design. Exemplified by a pseudo-zero-order reaction, the kinetics derivation from the Pt particle size-sensitive catalytic activity and size-insensitive activation energy suggests only one type of surface site as the dominant active site, in which the Pt(111) with almost unchanged turnover frequency (TOF111) is further identified as the dominating active site. Such a method has been extended to identify and quantify the number (Ni) of active sites for various thermo-, electro-, and photocatalysts in chemical synthesis, hydrogen generation, environment application, etc. Then, the kinetics derivation from the kinetic compensation effects suggests a thermodynamic balance between the activation entropy and enthalpy, which exhibit linear dependences on Pt charge. Accordingly, the Pt charge can serve as a catalytic descriptor for its quantitative determination of TOFi. This strategy has been further applied to Pt-catalyzed CO oxidation with nonzero-order reaction characteristic by taking the site coverages of surface species into consideration.Hence, substituting the above statistical correlations of Ni and TOFi into the rate equation R = ∑Ni × TOFi offers the mesokinetics model, which can precisely predict catalytic function and screen catalysts. Finally, based on the disentanglement of the factors underlying Pt electronic structures, a de novo strategy, from the interfacial charge distribution to reaction mechanism, kinetics, and thermodynamics parameters of the rate-determining step, and ultimately catalytic performance, is developed to map the unified mechanistic and kinetics picture of reaction. Overall, the mesokinetics not only demonstrates much potential to elucidate the quantitative interplay between active sites and catalytic activity but also provides a new research direction in kinetics analysis to rationalize catalyst design.


Subject(s)
Catalysis , Kinetics , Particle Size , Thermodynamics , Oxidation-Reduction
18.
Cancer Control ; 29: 10732748221132512, 2022.
Article in English | MEDLINE | ID: mdl-36346929

ABSTRACT

BACKGROUND: The cardiovascular toxicity of aromatase inhibitors (AIs) for women with estrogen receptor-positive breast cancer is controversial. We aimed to evaluate the association between AIs and the risk of myocardial infarction (MI) in women with estrogen receptor-positive breast cancer based on real-world studies. METHOD: PubMed, Embase, and Cochrane Library were searched to identify studies that estimated the association between MI risk and AIs. A random-effects model was used to evaluate the hazard ratio (HR) and 95% confidence intervals (CIs) of the predefined outcomes. RESULTS: A total of 134 476 patients from eight cohort studies were enrolled in our analysis. For MI incidence, no significant difference was found between the users of AIs and non-users (HR: .98, 95% CI: .83-1.17). The subgroup analysis of patients without a history of cardiovascular disease (CVD) suggested a reduced risk of MI (HR: .86, 95% CI: .77-.96). No significant difference was found for ischemic stroke (HR: .93, 95% CI: .82-1.07) and heart failure (HR: 1.24, 95% CI: .92-1.66) between the two groups. CONCLUSION: Based on real-world data, AIs may be a safe treatment route for patients with estrogen receptor-positive breast cancer and those with a history of CVD. AIs caused a major decrease in MI in patients without CVD history. However, more in-depth investigations are needed to explore the association between AI use and the incidence of MI in the treatment of estrogen receptor-positive breast cancer.


Subject(s)
Breast Neoplasms , Myocardial Infarction , Humans , Female , Aromatase Inhibitors/adverse effects , Breast Neoplasms/drug therapy , Receptors, Estrogen , Myocardial Infarction/chemically induced , Myocardial Infarction/epidemiology , Incidence
19.
Angew Chem Int Ed Engl ; 61(51): e202215225, 2022 Dec 19.
Article in English | MEDLINE | ID: mdl-36269685

ABSTRACT

Precisely tailoring the distance between adjacent metal sites to match adsorption configurations of key species for the targeted reaction pathway is a great challenge in heterogeneous catalysis. Here, we report a proof-of-concept study on the atomically sites-tailored pathway in Pd-catalyzed acetylene hydrogenation, i.e., increasing the distance of adjacent Pd atoms (dPd-a-Pd ) for configuration matching in acetylene semi-hydrogenation against coupling. dPd-a-Pd is identified as a structural descriptor for describing the competitiveness for reaction pathways, and the increased dPd-a-Pd prefers the semi-hydrogenation pathway due to simultaneously promoted C2 H4 desorption and the destabilized transition state of the C2 H3 * coupling. Spectroscopic, kinetics and electronic structure studies reveal that increasing dPd-a-Pd to 3.31 Šdelivers superior selectivity and stability due to energy matching and appropriate hybridization of Pd 4d with In 2s and, especially, 2p orbitals.

20.
ACS Appl Mater Interfaces ; 14(43): 49082-49093, 2022 Nov 02.
Article in English | MEDLINE | ID: mdl-36256731

ABSTRACT

Heat dissipation efficiency and electromagnetic interference (EMI) shielding performance are vital to integration, miniaturization, and application of electronic devices. Flexible and designable polymer-based composites are promising candidates but suffer from unavoidable interfacial thermal resistances, anisotropic thermal conductivity, and low shielding of EMI limiting application. Herein, multifunctional epoxy resin (EP)-based composites with an interconnected carbon fibers (CFs) network structure containing a low thermal resistance interfacial were prepared by high-temperature calcination and infiltration. The coherent heat and electron transfer pathways constructed with self-oriented CFs cloth connected by carbon nanotubes (CNTs) converted from leaf-shaped zeolitic imidazolate frameworks (ZIF-L) and stable magnetic property provided by cobalt nanoparticles contained in the CNTs made composites to an integrated in-plane thermal conductivity of up to 7.50 W m-1 K-1, a through-plane thermal conductivity of 1.96 W m-1 K-1, and an EMI shielding effectiveness of 38.4 dB. Furthermore, the mechanical properties of CFs and the junction effect of CNTs endowed the composites with stability of mechanical property, thermal conductivity, and EMI shielding effectiveness after multiple bendings. The finite element simulation further verified the advantage of CFs network linked by CNTs on heat transfer. This work provides the desired design for the construction of a multifunctional polymer-based composite used in advanced electronic equipment.

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