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CO oxidation has been studied for more than a century; however, molecular-level understanding of its activation protocol and related intermediates remains elusive. Here, we present a unified mechanistic and kinetic picture of various electronic metal-support interactions within platinum-carbon catalysts via in situ spectroscopic/kinetic analyses and multi-scale simulations. Transient kinetic analysis and molecular dynamics simulations with a reactive force field provided a quantitative description of the competition between the oxygen association and oxygen dissociation mechanisms tuned by the interfacial charge distribution and CO coverage. Steady-state isotopic transient kinetic analysis and density functional theory calculations revealed a simultaneous shift in the rate-determining step (RDS) from O2 * dissociation to O* and CO* and O2 * and CO* association. A de novo strategy from the interfacial charge distribution to the reaction mechanism, kinetics/thermodynamics of RDS, and, ultimately, catalytic performance was developed to quantitatively map the above CO activation mechanism with an order-of-magnitude increase in reactivity. The proposed catalytic picture and de novo strategy are expected to prompt the development of theories and methodologies for heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Background: Sjögren's syndrome (SS) is a common rheumatic disease for which finding the right imaging tool remains a challenge. Purpose: This study aimed to evaluate the performance of salivary gland ultrasonography (SGUS), shear wave elastography (SWE) and their combined use for the diagnosis of primary and secondary SS (pSS and sSS). Methods: This retrospective study included patients with dry symptoms who underwent routine examinations between May 2019 and December 2023. Patients were categorized into the pSS (n = 41), sSS (n = 26), and control (n = 27) groups based on the American College of Rheumatology/European League Against Rheumatism classification criteria (2016). A comparison of SGUS and shear wave velocity (SWV) results was conducted among the three groups. The diagnostic capabilities of different ultrasound methods for SS were evaluated using receiver operating characteristic (ROC) curves and the area under the curve (AUC) for specificity. Results: Compared to the control group, both the pSS (1.80 ± 1.03 vs. 0.67 ± 0.48, p < 0.001) and the sSS (1.85 ± 0.88 vs. 0.67 ± 0.48, p < 0.001) groups exhibited significantly elevated SGUS scores. However, there was no statistically significant difference between the pSS and sSS groups (p = 0.849). The SWV values in both the pSS and sSS groups were significantly higher than those in the control group (all p < 0.001). The AUC for diagnosing SS using only SGUS scores was 0.823 (95% confidence interval [CI]: 0.731–0.894). Combining SGUS scores and SWV values resulted in improved diagnostic accuracy (AUC: 0.883, 95% CI: 0.801–0.940). Conclusions: SGUS and SWE are pivotal in the diagnosis of Sjögren's syndrome, with their synergistic application poised to bolster diagnostic precision. This combined approach also furnishes substantial backing for the clinical assessment and management of Sjögren's syndrome. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusion This study aimed to investigate the clinical and laboratory characteristics of salivary gland ultrasonography (SGUS)‐positive patients with primary Sjögren's syndrome (pSS) compared to SGUS‐negative patients and to analyse the diagnostic value of SGUS and labial salivary gland biopsy (LSGB) grading in pSS.A retrospective analysis of patients admitted to the Affiliated Hospital of Yangzhou University between May 2019 and November 2023 was conducted. According to the OMERACT scoring system, patients with pSS were divided into an SGUS‐negative group (score <2) and an SGUS‐positive group (score ≥2). The patient's age, gender, clinical symptoms, laboratory parameters and diagnostic examinations were compared and analysed, and Spearman correlation analysis was used to analyse the correlation between SGUS, LSGB and influencing factors.There was no significant difference in dry mouth, dry eyes, tooth loss, fever, joint pain, fatigue, interstitial lung disease or renal tubular acidosis between the two groups, although there were more patients with salivary gland enlargement in the SGUS‐positive group (p < 0.05). In terms of high levels of immunoglobulin G (IgG), high levels of rheumatoid factor (RF), anti‐nuclear antibody ≥1:320, anti‐Sjögren's syndrome A‐52KD and anti‐Sjögren's syndrome B, the number of cases in the SGUS‐positive group was greater than that in the SGUS‐negative group (p < 0.05). LSGB samples were graded per the Chisholm–Mason system with significant differences between multiple groups. SGUS score negatively correlated with age and positively correlated with LSGB grade.This study showed that the SGUS score positively correlated with LSGB grade in pSS patients and negatively correlated with patient age. Thus, SGUS and LSGB are consistent in the diagnosis of pSS to reflect the degree of salivary gland involvement, and patients who are SGUS positive have high RF and IgG levels, a variety of autoantibodies positive and a tendency toward salivary gland enlargement. [ABSTRACT FROM AUTHOR]