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1.
Medicine (Baltimore) ; 103(32): e39237, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39121305

RESUMO

BACKGROUND: The approach of total hip arthroplasty (THA) has long been controversial, and many studies have compared different approaches. However, there is still a lack of consistent conclusions and comprehensive, systematic comparisons and evaluations. METHODS: This study retrieved 7 databases: PubMed, Web of Science, Embase, Cochrane Library, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, and Wanfang Database. The search time ranged from the establishment of each database to November 1, 2023. Data analysis was performed using Review Manager 5.4, and outcome was presented as the weighed mean difference for continuous data and risk/odds ratio for dichotomous data. We used the Mantel-Haneszel method and random effects model to obtain the overall effects of the differences in the impact of 2 surgical methods on clinical outcomes in all included studies. RESULTS: A total of 33 articles were included in this study, including 14478 participants, 4911 participants in DAA group and 9567 participants in PA group. The visual analogue scale scores of the DAA group at 1 day and 2 days after THA were significantly lower than those of the PA group (mean difference [MD] = -0.56, 95% confidence interval [CI]: -0.83 to -0.30, P < .01) at 1 day and (MD = -0.67, 95% CI: -1.16 to -0.17, P = .01) at 2 days. The risk of intraoperative fracture (odds ratio = 2.18, 95% CI: 1.11-4.29, P = .05) and lateral femoral nerve injury (risk ratio = 7.84, 95% CI: 1.69-36.42, P < .01) in the DAA group was significantly higher than that of the PA group. The number of prostheses in the Lewinnek safe zone of the DAA group was significantly higher than that of the PA group (risk ratio = 1.13, 95% CI: 1.00-1.27, P = .05). The results showed no significant difference between the DAA group and the PA group in the time to stop using walking aids, dislocation rate, groin pain, incision complications, heterotopic ossification, intraoperative blood loss, and acetabular anterior (P > .05). CONCLUSION: Compared with the PA group, patients in the DAA group showed more ideal anatomical and imaging results, shorter hospital stay, and showing advantages in postoperative pain, but with a higher incidence of intraoperative complications.


Assuntos
Artroplastia de Quadril , Humanos , Artroplastia de Quadril/métodos , Artroplastia de Quadril/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento
2.
ACS Appl Mater Interfaces ; 16(12): 14669-14679, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38498683

RESUMO

Mn-rich P2-type layered oxide cathode materials suffer from severe capacity loss caused by detrimental phase transition and transition metal dissolution, making their implementation difficult in large-scale sodium-ion battery applications. Herein, we introduced a high-valent Sb5+ substitution, leading to a biphasic P2/O3 cathode that suppresses the P2-O2 phase transformation in the high-voltage condition attributed to the stronger Sb-O covalency that introduces extra electrons to the O atom, reducing oxygen loss from the lattices and improving structural stability, as confirmed by first-principle calculations. Besides, the enhanced Na+ diffusion kinetics and thermodynamics in the modified sample are associated with the enlarged lattice parameters. As a result, the proposed cathode delivers a discharge capacity of 142.6 mAh g-1 at 0.1C between 1.5 and 4.3 V and excellent performance at a high mass loading of 8 mg cm3 with a specific capacity of 131 mAh g-1 at 0.2C. Furthermore, it also possesses remarkable rate capability (90.3 mAh g-1 at 5C), specifying its practicality in high-energy-density sodium-ion batteries. Hence, this work provides insights into incorporating high-valent dopants for high-performance Mn-rich cathodes.

3.
Chemistry ; 29(14): e202203977, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36576084

RESUMO

The electrochemical reduction of carbon dioxide (CO2 ) to value-added chemicals is a promising strategy to mitigate climate change. Metalloporphyrins have been used as a promising class of stable and tunable catalysts for the electrochemical reduction reaction of CO2 (CO2 RR) but have been primarily restricted to single-carbon reduction products. Here, we utilize functionalized earth-abundant manganese tetraphenylporphyrin-based (Mn-TPP) molecular electrocatalysts that have been immobilized via electrografting onto a glassy carbon electrode (GCE) to convert CO2 with overall 94 % Faradaic efficiencies, with 62 % being converted to acetate. Tuning of Mn-TPP with electron-withdrawing sulfonate groups (Mn-TPPS) introduced mechanistic changes arising from the electrostatic interaction between the sulfonate groups and water molecules, resulting in better surface coverage, which facilitated higher conversion rates than the non-functionalized Mn-TPP. For Mn-TPP only carbon monoxide and formate were detected as CO2 reduction products. Density-functional theory (DFT) calculations confirm that the additional sulfonate groups could alter the C-C coupling pathway from *CO→*COH→*COH-CO to *CO→*CO-CO→*COH-CO, reducing the free energy barrier of C-C coupling in the case of Mn-TPPS. This opens a new approach to designing metalloporphyrin catalysts for two carbon products in CO2 RR.

4.
J Am Chem Soc ; 144(42): 19417-19429, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36226909

RESUMO

Crystals are known to grow nonclassically or via four classical modes (the layer-by-layer, dislocation-driven, dendritic, and normal modes, which generally involve minimal interfacet surface diffusion). The field of nanoscience considers this framework to interpret how nanocrystals grow; yet, the growth of many anisotropic nanocrystals remains enigmatic, suggesting that the framework may be incomplete. Here, we study the solution-phase growth of pentatwinned Au nanorods without Br, Ag, or surfactants. Lower supersaturation conditions favored anisotropic growth, which appeared at variance with the known modes. Temporal electron microscopy revealed kinetically limited adatom funneling, as adatoms diffused asymmetrically along the vicinal facets (situated inbetween the {100} side-facets and {111} end-facets) of our nanorods. These vicinal facets were perpetuated throughout the synthesis and, especially at lower supersaturation, facilitated {100}-to-vicinal-to-{111} adatom diffusion. We derived a growth model from classical theory in view of our findings, which showed that our experimental growth kinetics were consistent with nanorods growing via two modes simultaneously: radial growth occurred via the layer-by-layer mode on {100} side-facets, whereas the asymmetric interfacet diffusion of adatoms to {111} end-facets mediated longitudinal growth. Thus, shape anisotropy was not driven by modulating the relative rates of monomer deposition on different facets, as conventionally thought, but rather by modulating the relative rates of monomer integration via interfacet diffusion. This work shows how controlling supersaturation, a thermodynamic parameter, can uncover distinct kinetic phenomena on nanocrystals, such as asymmetric interfacet surface diffusion and a fundamental growth mode for which monomer deposition and integration occur on different facets.


Assuntos
Nanopartículas Metálicas , Nanotubos , Nanopartículas Metálicas/química , Nanotubos/química , Anisotropia , Cinética , Tensoativos
5.
Nanomaterials (Basel) ; 12(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35745365

RESUMO

Polyserotonin nanoparticles (PSeNP) and films are bioinspired nanomaterials that have potential in biomedical applications and surface coatings. As studies on polyserotonin (PSe) nanoparticles and films are still in their infancy, synthetic pathways and material development for this new class of nanomaterial await investigation. Here, we sought to determine how different buffers used during the polymerization of serotonin to form nanoparticles and films impact the physicochemical properties of PSe materials. We show that buffer components are incorporated into the polymer matrix, which is also supported by density functional theory calculations. While we observed no significant differences between the elasticity of nanoparticles synthesized in the different buffers, the nanoscale surface properties of PSe films revealed dissimilarities in surface functional groups influenced by solvent molecules. Overall, the results obtained in this work can be used towards the rational design of PSe nanomaterials with tailored properties and for specific applications.

6.
J Am Chem Soc ; 141(21): 8584-8591, 2019 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-31067857

RESUMO

The electrochemical reduction of CO2 has seen many record-setting advances in C2 productivity in recent years. However, the selectivity for ethanol, a globally significant commodity chemical, is still low compared to the selectivity for products such as ethylene. Here we introduce diverse binding sites to a Cu catalyst, an approach that destabilizes the ethylene reaction intermediates and thereby promotes ethanol production. We develop a bimetallic Ag/Cu catalyst that implements the proposed design toward an improved ethanol catalyst. It achieves a record Faradaic efficiency of 41% toward ethanol at 250 mA/cm2 and -0.67 V vs RHE, leading to a cathodic-side (half-cell) energy efficiency of 24.7%. The new catalysts exhibit an in situ Raman spectrum, in the region associated with CO stretching, that is much broader than that of pure Cu controls, a finding we account for via the diversity of binding configurations. This physical picture, involving multisite binding, accounts for the enhanced ethanol production for bimetallic catalysts, and presents a framework to design multimetallic catalysts to control reaction paths in CO2 reductions toward desired products.

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