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Abstract Introduction For effective preventive strategies against GORD (gastro-esophageal reflux disease), we assessed the GORD burden from 1990 to 2019. Methods The burden of GORD between 1990 and 2019 was evaluated globally, regionally, and nationally. Using ASIR (age-standardized incidence), ASYLDs (age-standardized years lived with disabilitys), we compared them to the GBD world population per 100,000. The estimates were based on 95% uncertainty intervals (UIs). The AAPC (average annual percent change) in incidence, YLDs, along with prevalence rates with associated 95% CIs were estimated. Results Data to estimate the burden of GORD are scarce till now. The global ASIR of GORD in 2019 was 3792.79 per 100,000, an increase AAPC of 0.112% from 1990. The prevalence of GORD increased with a AAPC of 0.096% to 9574.45 per 100,000. Global ASYLDs in 2019 was 73.63, an increase AAPC of 0.105% from 1990. The GORD burden varies greatly depending on the development level and geographical location. USA demonstrated the most obvious decreasing trend in burden of GORD, while Sweden had an increasing trend. That the increase in GORD YLDs was mediated primarily by the growth and aging of population, was revealed by decomposition analyses. There was an inverse relationship between SDI (socio-demographic index) and GORD-burden. Frontier analyses revealed significant scope of improvement in the status of development at all levels. Conclusion GORD is a public health challenge, especially in Latin America. Some SDI quintiles had declining rates, while some countries experienced increased rates. Thus, resources should be allocated for preventative measures based on country-specific estimates.

The catalytic properties of metal oxides are often enabled by surface defects, and their characterization is thus vital to the understanding and application of metal oxide catalysts. Typically, surface defects for metal oxides show fingerprints in spectroscopic characterization. However, we found that synchrotron-radiation photoelectron spectroscopy (SRPES) is difficult to probe surface defects of ZnO. Meanwhile, CO as a probe molecule cannot be used properly to identify surface defect sites on ZnO in infrared (IR) spectroscopy. Instead, we found that formaldehyde could serve as a probe molecule, which is sensitive to surface defect sites and could titrate surface oxygen vacancies on ZnO, as evidenced in both SRPES and IR characterization. Density functional theory calculations revealed that formaldehyde dissociates to form formate species on the stoichiometric ZnO (10 1 ¯ 0) surface, while it dissociates to formyl species on Vo sites of the reduced ZnO (10 1 ¯ 0) surface instead. Furthermore, the mechanism of formaldehyde dehydrogenation on ZnO surfaces was also elucidated, while the generated hydrogen atoms are found to be stored in ZnO bulk from 423 K to 773 K, making ZnO an interesting (de)hydrogenation catalyst. [ABSTRACT FROM AUTHOR]

Revealing the fundamental mechanisms governing reactant-induced disintegration of supported metal nanoparticles and their dependences on the metal component and reactant species is vital for improving the stability of supported metal nanocatalysts and single-atom catalysts. Here we use first-principles based disintegration thermodynamics to study the CO- and OH- induced disintegration of Ag, Cu, Au, Ni, Pt, Rh, Ru, and Ir nanoparticles into metal-reactant complexes (M(CO)n, M(OH)n, n=1 and 2) on the pristine and bridge oxygen vacancy site of TiO2(110). It was found that CO has a stronger interaction with these considered transition metals compared to OH, resulting in lower formation energy and a larger promotion effect on the disintegration of nanoparticles (NPs). The corresponding reactant adsorption energy shows a linear dependence on the metal cohesive energy, and metals with higher cohesive energies tend to have higher atomic stability due to their stronger binding with reactant and support. Further disintegration free energy calculations of NPs into metal-reactant complexes indicate only CO-induced disintegration of Ni, Rh, Ru, and Ir nanoparticles is thermodynamically feasible. These results provide a deeper understanding of reactant-induced disintegration of metal nanoparticles into thermodynamically stable metal single-atom catalysts. [ABSTRACT FROM AUTHOR]

Dissolution is the primary route of Pt nanoparticle degradation in electrochemical devices, e.g., fuel cells. Investigation of potential-dependent dissolution kinetics of Pt nanoparticles is crucial to optimize the nanoparticle size and operating conditions for better performance. A mean-field kinetic theory under the steady-state approximation, combined with atomistic thermodynamics and Wulff construction, was developed to study the interplay between oxygen chemisorption, electrode potential, and particle size on the dissolution of Pt nanoparticles. We found that although oxygen chemisorption from electrode potential-induced water splitting can stabilize Pt nanoparticles through decreasing the surface energy and increasing the redox potential, the electrode potential plays a more decisive role in facilitating the dissolution of Pt nanoparticles. In comparison with the minor effect of oxygen chemisorption, an increase in the particle size, though reducing the dispersion, has a more significant effect on the suppression of the dissolution. These theoretical understandings on the effects of electrode potential and particle size on the dissolution are crucial for optimizing the nanoparticle size under oxidative operating conditions. [ABSTRACT FROM AUTHOR]