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1.
Langmuir ; 40(19): 10384-10392, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38698714

RESUMO

The oxygen evolution reaction (OER), a crucial semireaction in water electrolysis and rechargeable metal-air batteries, is vital for carbon neutrality. Hindered by a slow proton-coupled electron transfer, an efficient catalyst activating the formation of an O-H bond is essential. Here, we proposed a straightforward one-step hydrothermal procedure for fabricating PO43--modified NiFe layered double-hydroxide (NiFe LDH) catalysts and investigated the role of PO43- anions in enhancing OER. Phosphate amounts can efficiently regulate LDH morphology, crystallinity, composition, and electronic configuration. The optimized sample showed a low overpotential of 267 mV at 10 mA cm-2. Density functional theory calculations revealed that intercalated and surface-adsorbed PO43- anions in NiFe LDH reduced the Gibbs free energy in the rate-determining step of *OOH formation, balancing oxygen-containing intermediate adsorption/dissociation and promoting the OER. Intercalated phosphate ions accelerated precatalyst dehydrogenation kinetics, leading to a rapid reconstruction into active NiFe oxyhydroxide species. Surface-adsorbed PO43- interacted favorably with adsorbed *OOH on the active Ni sites, stabilizing *OOH. Overall, the synergistic effects of intercalated and surface-adsorbed PO43- anions significantly contributed to enhanced OER activity. Achieving optimal catalytic activity requires a delicate equilibrium between thermodynamic and kinetic factors by meticulously regulating the quantity of introduced PO43- ions. This endeavor will facilitate a deeper comprehension of the influence of anions in electrocatalysis for OER.

2.
J Neuroimaging ; 31(2): 261-271, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33270962

RESUMO

BACKGROUND AND PURPOSE: Source-based morphometry(SBM) has been used in multicenter studies pooling magnetic resonance imaging data across different scanners to advance the reproducibility of neuroscience research. In the present study, we developed an analysis strategy for Scanner-Specific Detection (SS-Detect) of SBPs in multiscanner studies, and evaluated its performance relative to a conventional strategy. METHODS: In the first experiment, the SimTB toolbox was used to generate simulated datasets mimicking 20 different scanners with common and scanner-specific SBPs. In the second experiment, we generated one simulated SBP from empirical gray matter volume (GMV) datasets from two different scanners. Moreover, we applied two strategies to compare SBPs between schizophrenia patients' and healthy controls' GMV from two scanners. RESULTS: The outputs of the conventional strategy were limited to whole-sample-level results across all scanners; the outputs of SS-Detect included whole-sample-level and scanner-specific results. In the first simulation experiment, SS-Detect successfully estimated all simulated SBPs, including the common and scanner-specific SBPs, whereas the conventional strategy detected only some of the whole-sample SBPs. The second simulation experiment showed that both strategies could detect the simulated SBP. Quantitative evaluations of both experiments demonstrated greater accuracy of the SS-Detect in estimating spatial SBPs and subject-specific loading parameters. In the third experiment, SS-Detect detected more significant between-group SBPs, and these SBPs corresponded with the results from voxel-based morphometry analysis, suggesting that SS-Detect has higher sensitivity in detecting between-group differences. CONCLUSIONS: SS-Detect outperformed the conventional strategy and can be considered advantageous when SBM is applied to a multiscanner study.


Assuntos
Imageamento por Ressonância Magnética/instrumentação , Adulto , Estudos de Casos e Controles , Substância Cinzenta/diagnóstico por imagem , Humanos , Masculino , Reprodutibilidade dos Testes , Esquizofrenia/diagnóstico por imagem
3.
Research (Wash D C) ; 2020: 5860712, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33029589

RESUMO

Numerous experiments have demonstrated that the metal atom is the active center of monoatomic catalysts for hydrogen evolution reaction (HER), while the active sites of nonmetal doped atoms are often neglected. By combining theoretical prediction and experimental verification, we designed a unique ternary Ru-N4-P coordination structure constructed by monodispersed Ru atoms supported on N,P dual-doped graphene for highly efficient hydrogen evolution in acid solution. The density functional theory calculations indicate that the charge polarization will lead to the most charge accumulation at P atoms, which results in a distinct nonmetallic P active sites with the moderate H∗ adsorption energy. Notably, these P atoms mainly supply highly efficient catalytic sites with ultrasmall absorption energy of 0.007 eV. Correspondingly, the Ru-N4-P demonstrated outstanding HER performance not only in an acidic condition but also in alkaline environment. Notably, the performance of Ru-NPC catalyst at high current is even superior to the commercial Pt/C catalysts, whether in acidic or alkaline medium. Our in situ synchrotron radiation infrared spectra demonstrate that a P-Hads intermediate is continually emerging on the Ru-NPC catalyst, actively proving the nonmetallic P catalytically active site in HER that is very different with previously reported metallic sites.

4.
J Phys Chem Lett ; 10(20): 6081-6087, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31539474

RESUMO

Rationally designing cheap and efficient electrocatalysts at the atomic level is highly desirable for the hydrogen evolution reaction (HER). Here, we demonstrate a metallic MoS2 electrocatalyst decorated with platinum single atoms. When combined with electron microscopy observations, our synchrotron X-ray characterizations and theoretical calculations clearly reveal that the doped Pt atoms bond to S atoms on the surface of MoS2. Notably, these Pt single atoms serve as critical active centers for the HER through capturing H+ from the solution. The optimized Pt-MoS2 catalysts achieve significantly enhanced HER performance due to the single-atom coordination effect. This finding is expected to facilitate further realization of hybridized catalysts through the monatomic riveting strategy.

5.
ACS Nano ; 13(10): 11733-11740, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31525961

RESUMO

Molybdenum disulfide (MoS2) has attracted much attention as a promising alternative to Pt-based catalysts for highly efficient hydrogen generation. However, it suffers sluggish kinetics for driving the hydrogen evolution reaction (HER) process because of inert basal planes, especially in alkaline solution. Here, we show a combination of heteroatom doping and phase transformation strategies to engineer the in-plane structure of MoS2, that trigger their catalytic activities. Systematic characterizations are performed with advanced aberration-corrected microscopy and X-ray techniques, indicating that an as-designed MoS2 catalyst has a distorted zigzag-chain superlattice in metallic phase, while its in-plane structure was engineered via the incorporation of cobalt and oxygen species. The optimal Co, O dual-doped metallic phase molybdenum disulfide (1T-MoS2) electrocatalyst shows a significantly enhanced HER activity with a low overpotential of 113 mV at 10 mA cm-2 and corresponding small Tafel slope of 50 mV dec-1, accompanied by the robust stability in alkaline media. The calculated turnover frequency is higher than 6.65 H2 s-1 at an overpotential of 200 mV. More in-depth insights from the first-principle calculations illustrate that the water dissociation as a rate-determining step was largely accelerated by the in-plane Co-O-Mo species and fast electron transfer of the catalyst. Benefiting from ingenious design and fine identifications, this work provides a fundamental understanding of the relationships among heteroatom doping, phase transformation, and performance for MoS2-based catalysts.

6.
J Phys Chem Lett ; 9(4): 817-824, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29389134

RESUMO

Atomic intercalation of different agents into 2D layered materials can engineer the intrinsic structure on the atomic scale and thus tune the physical and chemical properties for specific applications. Here we successfully introduce tin (Sn) atoms into the interlayer of α-MoO3 nanobelts forming a new MoO3-Sn intercalation with ultrastable structure. Combining with theoretical calculations, our synchrotron radiation-based characterizations and electron microscope observations clearly reveal that the intercalated Sn atoms could bond with five O atoms, forming a pentahedral structure. Subsequently, the Sn-O bonds induce a less distorted [MoO6] octahedral structure, resulting in a unique structure that is distinct with pristine α-MoO3 or any other molybdenum oxides. Employed as anode for lithium-ion battery, the as-prepared MoO3-Sn nanobelts display a much higher capacity of 520 mAhg-1 at 500 mAg-1 than α-MoO3 nanobelts (291 mAhg-1), with a Coulombic efficiency of 99.5%. Moreover, owing to the strong intercalation from Sn ions, the MoO3-Sn nanobelts pose superior cyclability, durability, and reliability.

7.
EuroIntervention ; 12(8): e957-e963, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-26690316

RESUMO

AIMS: The study aimed to examine five-year clinical outcomes of complete (CR), partially complete (PCR), and incomplete revascularisation (ICR) in patients with unprotected left main coronary artery (ULMCA) disease treated with drug-eluting stents (DES). Completeness of revascularisation, defined as revascularisation of all vessels ≥1.5 or 2.5 mm in diameter, has been shown to correlate with outcomes after percutaneous coronary intervention (PCI). There are no data to compare revascularisation strategies on long-term clinical outcomes in patients undergoing PCI of ULMCA disease. METHODS AND RESULTS: This prospective registry enrolled 910 consecutive patients with ULMCA disease undergoing PCI with DES implantation. CR included patients who had a successful revascularisation of all diseased segments with diameter ≥1.5 mm. PCR included patients who had successful revascularisation of all diseased segments with diameter ≥2.5 mm. ICR included patients who did not achieve revascularisation for all diseased segments of diameter ≥2.5 mm. The primary endpoint was the incidence of major adverse cardiac events (MACE: a composite of cardiac death, myocardial infarction and repeat revascularisation) at five-year follow-up. CR was achieved in 386 (42.4%), PCR in 227 (25.0%), and ICR in 297 (32.6%) patients. Patients with ICR had a significantly higher rate of MACE (29.6% vs. 22.5% and 15.5%, p<0.001) and all-cause mortality (12.5% vs. 7.0% and 6.2%; p=0.006) than those with CR and PCR at five-year follow-up. After propensity score matching, patients with CR vs. PCR had similar incidences of MACE (hazard ratio [HR]: 1.16, 95% confidence interval [CI]: 0.78-1.74, p=0.46), mortality (HR: 1.27, 95% CI: 0.61-2.63, p=0.53), and cardiac death (1.8% vs. 4.5%; HR: 2.56, 95% CI: 0.80-8.17, p=0.11). On multivariable logistic regression analysis, ICR appears to be an outcome of poor clinical characteristics, comorbidities and complex coronary anatomy. CONCLUSIONS: In the treatment of patients with ULMCA disease, ICR was associated with worse long-term clinical outcomes than CR and PCR. PCR has clinical outcomes similar to CR in patients with ULMCA disease treated with DES.


Assuntos
Doenças Cardiovasculares/mortalidade , Doença da Artéria Coronariana/cirurgia , Stents Farmacológicos , Infarto do Miocárdio/epidemiologia , Revascularização Miocárdica/estatística & dados numéricos , Intervenção Coronária Percutânea/métodos , Sistema de Registros , Fatores Etários , Idoso , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Hipertensão/epidemiologia , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Doenças Vasculares Periféricas/epidemiologia , Pontuação de Propensão , Modelos de Riscos Proporcionais , Estudos Prospectivos , Resultado do Tratamento
8.
EuroIntervention ; 8(7): 803-14, 2012 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-23171801

RESUMO

AIMS: The present study aimed to compare the long-term (five-year) safety and efficacy between the one-stent, two-stent and double-kissing (DK) crush strategies, utilising drug-eluting stents, for unprotected left main coronary artery (ULMCA) bifurcation lesions. METHODS AND RESULTS: Between March 2004 and April 2007, 633 consecutive patients with ULMCA bifurcation lesions (232 in the one-stent group and 401 in the two-stent group) were prospectively enrolled. The primary endpoint was the occurrence of major adverse cardiac events (MACE), a composite of cardiac death, myocardial infarction (MI), and target vessel revascularisation (TVR), at five-year follow-up. Patients in the the two-stent group were classified as DK crush (n=155) and other two-stent techniques (culotte, T-stenting, kissing stenting and classical crush, n=246). Forty-seven (16.8%) patients in the one-stent group crossed over to the two-stent group. The one-stent group was associated with an increased incidence of MI compared to the two-stent approach (10.5% vs. 5.5%, p=0.025). The crude rate of MACE at five years was 28.0% in the one-stent group and 28.4% in the two-stent group (p=0.927). DK crush was associated with a significantly decreased five-year MACE compared to the other two-stent approaches or the one-stent approach (DK crush: 14.8% vs. other two-stent approaches: 37.0%, one-stent approach: 28.0%, p<0.001). The main benefit of DK crush primarily appeared to be secondary to a reduction in TVR (7.7% vs. 30.5% vs. 18.1%, p<0.001). By Cox regression analyses, the non-DK crush two-stent technique, a high SYNTAX Score (≥33) or New Risk Stratification (NERS) score (>20), and incomplete revascularisation were shown to be independent predictors of MACE at five-year follow-up. CONCLUSIONS: With distal left main true bifurcations, the two-stent technique (excluding DK crush) is an independent predictor of long-term MACE. DK crush is associated with more favourable long-term clinical outcomes. Confirmation of these findings is required from randomised controlled trials.


Assuntos
Angioplastia Coronária com Balão/instrumentação , Angioplastia Coronária com Balão/métodos , Estenose Coronária/terapia , Stents Farmacológicos , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Angioplastia Coronária com Balão/mortalidade , Distribuição de Qui-Quadrado , China/epidemiologia , Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/epidemiologia , Modelos de Riscos Proporcionais , Estudos Prospectivos , Desenho de Prótese , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
9.
Chin Med J (Engl) ; 125(12): 2083-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22884133

RESUMO

BACKGROUND: The predictive value of bifurcation angle (BA) for worse events after stenting bifurcation lesions remains to be unknown. The present study was to investigate the dynamic change of BA and clinical relevance for patients with coronary bifurcation lesions treated by drug-eluting stent (DES). METHODS: BA was calculated by 3-D quantitative coronary analysis from 347 patients in DKCRUSH-II study. Primary endpoint was the occurrence of composite major adverse cardiac events (MACE) at 12-month, including cardiac death, myocardial infarction (MI) and target vessel revascularization (TVR). Secondary end points were the rate of binary restenosis and stent thrombosis at 12-month. RESULTS: Stenting was associated with the reduction of distal BA. The cut-off value of distal BA for predicting MACE was 60°. Distal BA in < 60° group had less reduction after stenting ((-1.96 ± 13.58)° vs. (-12.12 ± 23.58)°, P < 0.001); two-stent technique was associated with significant reduction of distal BA (Δ(-4.05 ± 14.20)°), compared to single stent group (Δ + 1.55 ± 11.73, P = 0.003); the target lesion revascularization (TLR), TVR and MACE rate was higher in one-stent group (16.5%, 19.0% and 21.5%), compared to two-stent group (3.8%, P = 0.002; 7.5%, P = 0.016; and 9.8%, P = 0.024), respectively. Among patients in ≥ 60° group, there were no significant differences in distal BA, stent thrombosis (ST), MI, MACE, death, TLR, TVR between one- and two-stent groups; after stenting procedure, there was only slight change of distal BA in left anterior descending (LAD)-left circumflex (LCX) subgroup (from (88.54 ± 21.33)° at baseline to (82.44 ± 31.72)° post-stenting), compared to either LAD-diagonal branch (Di), or LCX-obtuse marginal branch (OM), or RCA distal (RCAd) (all P < 0.001). CONCLUSION: Two-stent technique was associated with significant reduction of distal BA. DK crush stenting had reduced rate of MACE in patients in < 60° group, compared to one-stent technique.


Assuntos
Angioplastia Coronária com Balão/efeitos adversos , Angioplastia Coronária com Balão/métodos , Doença da Artéria Coronariana/terapia , Adulto , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Feminino , Humanos , Masculino , Estudos Prospectivos , Adulto Jovem
10.
Chin Med J (Engl) ; 125(1): 7-11, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22340457

RESUMO

BACKGROUND: The gender-based differences in adverse events after drug-eluting stent (DES) implantation between Chinese women and men have not been fully studied. The present study aimed to compare the 5-year clinical outcome after DES implantation in Chinese women and men. METHODS: Chinese women (n = 298) and men (n = 698) with newly diagnosed de novo coronary lesions were studied after DES implantation. The primary endpoint was the occurrence of major adverse cardiac events (MACEs) over a 5-year follow-up, including myocardial infarction (MI), cardiac death, and target vessel revascularization (TVR). Propensity score matching (PSM) was used to compare the adjusted MACE rates between sexes. RESULTS: Women differed in body habitus and had increased fasting cholesterol. Fewer women presented with MI, and they had better cardiac function with less complex disease. The unadjusted rate of MI at 3 years (2.1%) and 5 years (5.0%) and MACE (25.2%) at 5 years in men was significantly higher than that of women (0.3%, 1.0% and 17.8%, P = 0.050, P = 0.032, and P = 0.011, respectively). After PSM, the adjusted adverse events between sexes were similar. The stent thrombosis rate rapidly increased after 2 years in men. CONCLUSIONS: There were significant gender-based differences in baseline characteristics. Chinese men had equivalent outcomes to women after DES after adjustment by PSM. The increased rate of MI in men was attributed to an increased unadjusted rate of MACE.


Assuntos
Angioplastia Coronária com Balão/métodos , Stents Farmacológicos , Infarto do Miocárdio/terapia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
11.
J Am Coll Cardiol ; 57(8): 914-20, 2011 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-21329837

RESUMO

OBJECTIVES: The present study aimed to investigate the difference in major adverse cardiac events (MACE) at 12 months in patients with coronary bifurcation lesions after double kissing double crush (DK crush) or provisional stenting (PS) techniques. BACKGROUND: Provisional side branch (SB) stenting is preferable to DK crush because it has been associated with fewer complications. It is unknown which strategy would provide the best results. METHODS: From April 2007 to June 2009, 370 unselected patients with coronary bifurcation lesions from 7 Asian centers were randomly assigned to either the DK or the PS group. Additional SB stenting in PS was required if final results were suboptimal. The primary end point was the occurrence of MACE at 12 months, including cardiac death, myocardial infarction, or target vessel revascularization (TVR). Secondary end point was the angiographic restenosis at 8 months. RESULTS: There were 3 procedural occlusions of SB in the PS group. At 8 months, angiographic restenosis rates in the main vessel and SB were significantly different between the DK (3.8% and 4.9%) and the PS groups (9.7% and 22.2%, p = 0.036 and p < 0.001, respectively). Additional SB stenting in the PS group was required in 28.6% of lesions. TVR was 6.5% in the DK group, occurring significantly less often than in the PS group (14.6%, p = 0.017). There were nonsignificant differences in MACE and definite stent thrombosis between the DK (10.3% and 2.2%) and PS groups (17.3%, and 0.5%, p = 0.070 and p = 0.372, respectively). CONCLUSIONS: DK crush was associated with a significant reduction of TLR and TVR in this unselected patient population. However, there was no significant difference in MACE between DK and the PS groups. (Randomized Study on DK Crush Technique Versus Provisional Stenting Technique for Coronary Artery Bifurcation Lesions; ChicTR-TRC-00000015).


Assuntos
Angioplastia Coronária com Balão/métodos , Reestenose Coronária/mortalidade , Estenose Coronária/mortalidade , Estenose Coronária/terapia , Stents Farmacológicos , Fatores Etários , Idoso , Angioplastia Coronária com Balão/mortalidade , China , Angiografia Coronária/métodos , Reestenose Coronária/diagnóstico por imagem , Reestenose Coronária/terapia , Estenose Coronária/diagnóstico por imagem , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Falha de Prótese , Medição de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Sirolimo/farmacologia , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
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