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We report the free energy barriers for the elementary reactions in the 2e− and 4e− oxygen reduction reaction (ORR) steps on Au(100) in an alkaline solution. Due to the weak adsorption energy of O2 on Au(100), the barrier for the association channel is very low, and the 2e− pathway is clearly favored, while the barrier for the O–O dissociation channel is significantly higher at 0.5 eV. Above 0.7 V reversible hydrogen electrode (RHE), the association channel becomes thermodynamically unfavorable, which opens up the O–O dissociation channel, leading to the 4e− pathway. The low adsorption energy of oxygenated species on Au is now an advantage, and residue ORR current can be observed up to the 1.0–1.2 V region (RHE). In contrast, the O–O dissociation barrier on Au(111) is significantly higher, at close to 0.9 eV, due to coupling with surface reorganization, which explains the lower ORR activity on Au(111) than that on Au(100). In combination with the previously suggested outer sphere electron transfer to O2 for its initial adsorption, these results provide a consistent explanation for the features in the experimentally measured polarization curve for the alkaline ORR on Au(100) and demonstrate an ORR mechanism distinct from that on Pt(111). It also highlights the importance to consider the spin state of O2 in ORR and to understand the activation barriers, in addition to the adsorption energies, to account for the features observed in electrochemical measurements. [ABSTRACT FROM AUTHOR]

ABSTRACT In the context of numerical simulators for multiphase flow in porous media, there exists a long‐standing issue known as the grid orientation effect (GOE), wherein different numerical solutions can be obtained when considering grids with different orientations under certain unfavorable conditions. The GOE is relevant to the instability near displacement fronts. If numerical oscillations accompanied by sharp fronts are not adequately suppressed, the GOE occurs. To reduce or even eliminate the GOE, we propose augmenting adaptive artificial viscosity in the process of solving the saturation equation. It has been demonstrated that appropriate artificial viscosity can effectively reduce or even eliminate the GOE. The proposed numerical method can be easily applied in practical engineering problems. [ABSTRACT FROM AUTHOR]

ABSTRACT In this work, we improve the traditional adaptive mesh refinement (AMR) by combining it with the finite analytical method (FAM) to solve the multiphase flow in heterogeneous porous media numerically. The FAM can provide rather accurate internodal transmissibility, and it is employed to improve the accuracy of coarsening and refining processes in AMR. The high performance of the proposed AMR‐FAM is indicated through numerical tests for solving the two‐phase flow in 2D heterogeneous media. The numerical simulation results indicate that the proposed AMR‐FAM is more accurate than the traditional AMR‐FAM. Compared with the simulation in the original fine grids, the proposed AMR‐FAM can provide nearly the same results. Moreover, the computational cost in the AMR grids is only approximately one‐third of the cost in the original fine grids according to our numerical tests. [ABSTRACT FROM AUTHOR]

The patient is a 12-year-old male who has experienced recurrent perianal abscesses for over 10 years, along with recurrent oral ulcers and deformities in the joints of hands and feet. Gastrointestinal endoscopy and capsule endoscopy revealed multiple ulcers in the digestive tract. Combined with his histopathological examinations, the patient was diagnosed with Crohn's disease. Whole exome sequencing and peripheral blood karyotype analysis indicated a karyotype of 47,XY,+8. The patient was treated with a "step-up" strategy. His clinical symptoms were under control, with significant improvement observed during endoscopic examination. This case suggests that early-onset inflammatory bowel disease may have genetic susceptibility, and when accompanied by other multi-system involvement, the possibility of chromosomal abnormalities, such as trisomy 8, should be considered and given due attention.

Background: Upper respiratory tract infection (URTI), one of the most common respiratory diseases, has a high annual incidence. Trollius chinensis capsule has been used to treat URTI in China. However, the underlying-mechanisms remain unclear., Methods: Network pharmacology was used to explore the potential mechanism of action of Trollius chinensis capsule in URTI treatment. The active compounds in Trollius chinensis were obtained from the TCMSP, SymMap, and ETCM databases. The TCMSP, PubChem, and SwissTargetPrediction databases were used to predict potential targets of Trollius chinensis. URTI-associated targets were gathered from GeneCards and DisGeNET databases. The key targets and signaling pathways associated with URTI were selected by network topology, GO, and KEGG pathway enrichment analysis. Molecular docking was used to verify the binding activity between active compounds and key targets., Results: Quercetin, pectolinarigenin, beta-sitosterol, acacetin and cirsimaritin are major active compounds in Trollius chinensis capsule. Eighty one candidate therapeutic targets were confirmed to be involved in protection of Trollius chinensis capsule against URTI. Among them, 7 key targets (TP53, IL6, AKT1, CASP3, CXCL8, MMP9, and EGFR) were verified to have good binding affinities to the main active compounds. Furthermore, enrichment analyses suggested that inflammatory response, virus infection and oxidative stress related biological processes and pathways were possibly the potential mechanism., Conclusion: Overall, the present study clarified that quercetin, pectolinarigenin, beta-sitosterol, acacetin and cirsimaritin are proved to be the main effective compounds of Trollius chinensis capsule treating URTI, possibly by acting on the targets of IL6, AKT1, CASP3, CXCL8, MMP9 and EGFR to play anti-infectious, anti-viral, and anti-oxidative effects. This study provides a new understanding of the active compounds and mechanisms of Trollius chinensis capsule in URTI treatment from the perspective of network pharmacology., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

We report the free energy barriers for the elementary reactions in the 2e- and 4e- oxygen reduction reaction (ORR) steps on Au(100) in an alkaline solution. Due to the weak adsorption energy of O2 on Au(100), the barrier for the association channel is very low, and the 2e- pathway is clearly favored, while the barrier for the O-O dissociation channel is significantly higher at 0.5 eV. Above 0.7 V reversible hydrogen electrode (RHE), the association channel becomes thermodynamically unfavorable, which opens up the O-O dissociation channel, leading to the 4e- pathway. The low adsorption energy of oxygenated species on Au is now an advantage, and residue ORR current can be observed up to the 1.0-1.2 V region (RHE). In contrast, the O-O dissociation barrier on Au(111) is significantly higher, at close to 0.9 eV, due to coupling with surface reorganization, which explains the lower ORR activity on Au(111) than that on Au(100). In combination with the previously suggested outer sphere electron transfer to O2 for its initial adsorption, these results provide a consistent explanation for the features in the experimentally measured polarization curve for the alkaline ORR on Au(100) and demonstrate an ORR mechanism distinct from that on Pt(111). It also highlights the importance to consider the spin state of O2 in ORR and to understand the activation barriers, in addition to the adsorption energies, to account for the features observed in electrochemical measurements., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)