Subangstrom Profile Imaging of Relaxed ZnO(101̅0) Surfaces

Relaxation is a most basic structural behavior of free surfaces, however, direct observation of surface relaxation remains challenging in atomic-scale. Herein, single-crystalline nanoislands formed in situ on ZnO nanowires and nanobelts are characterized using aberration-corrected transmission electron microscopy combined with ab initio calculations. For the first time, displacements of both Zn and O atoms in the fresh (101̅0) facets are quantified to accuracies of several picometers and the under-surface distributions of contractions and rotations of Zn–O bonds are directly measured, which unambiguously verify the theoretically predicted relaxation of ZnO (101̅0) free surfaces. Finally, the surface relaxation is directly correlated with the size effects of electromechanical properties (e.g., elastic modulus and spontaneous polarization) in ZnO nanowires

Strain Concentration at the Boundaries in 5‑Fold Twins of Diamond and Silicon

Widely found in metals, semiconductors, oxides, and even organic materials, multiple twinning has important implications in engineering applications of materials. In this work, the intrinsic strain in 5-fold twins of diamond and silicon has been studied combining aberration-corrected electron microscopy and first-principles calculations. In contrast to metallic 5-fold twins, where the strain distribution is relatively smooth, the semiconductor systems show significant strain concentration at the twin boundaries, which is shear modulus dependent. In silicon with moderate strain concentration, the electronic frontier orbitals are located at the center of the 5-fold twins. Accompanying the increased strain concentration in diamond, however, the frontier orbitals are pushed to the surface. The modification of strain state and surface electronic structure by materials elasticity suggest possible routes to tune catalytic, electronic, and mechanical properties of materials

Table_1_A Mendelian randomization study of the effect of serum 25-hydroxyvitamin D levels on autoimmune thyroid disease.docx

ObjectiveThe influence of vitamin D on autoimmune thyroid disease (AITD) remains a subject of ongoing debate. This study employs Mendelian randomization (MR) to investigate the causal correlations of serum 25-hydroxyvitamin D (25[OH]D) levels with autoimmune thyroiditis (AIT), autoimmune hyperthyroidism (AIH), and Graves disease (GD).MethodsData on single nucleotide polymorphisms related to serum 25(OH)D levels, AIT, AIH, and GD were sourced from UK Biobank and FinnGen. Inverse variance weighted, MR-Egger, and weighted median were employed to test the exposure-outcome causal relationship. Assessments of horizontal pleiotropy, heterogeneity, and stability were performed using the MR-Egger intercept, Cochran’s Q test, and leave-one-out sensitivity analysis, respectively.ResultsThe results of MR analysis showed increased serum 25(OH)D levels was associated with a reduced risk of AIT (OR 0.499, 95% CI 0.289 to 0.860, p = 0.012) but not causal associated with AIH (OR 0.935, 95% CI 0.695 to 1.256, p = 0.654) and GD (OR 0.813, 95% CI 0.635 to 1.040, p = 0.100). Intercept analysis showed no horizontal pleiotropy (p > 0.05), and Cochran’s Q test showed no heterogeneity (p > 0.05). Sensitivity analysis suggested that these results were robust.ConclusionAn increased serum 25(OH)D level is associated with AIT risk reduction but unrelated to AIH and GD. This finding suggests that vitamin D supplementation can be valuable for preventing and treating AIT.</p

Additional file 1 of Post-trigger luteinizing hormone concentration to positively predict oocyte yield in the antagonist protocol and its association with genetic variants of LHCGR

Additional file 1: Supplemental Table 1. Descriptive date and genotype frequencies of 372 patients. Supplemental Figure 1. The body mass index (BMI), LH concentrations and number of high-quality embryos of patients grouped by oocyte retrieval rate (ORR) quartile in cycles with GnRH-a triggering

Table_1_Effect of tea intake on genetic predisposition to gout and uric acid: a Mendelian randomization study.docx

ObjectiveThe effect of tea on gout and uric acid is still controversial. This study aims to analyze the effect of tea intake on genetic predisposition to gout, idiopathic gout, gout due to impairment of renal function as well as uric acid by Mendelian randomization (MR).MethodsForty independent single nucleotide polymorphisms (SNPs) associated with tea intake were selected from UK Biobank. SNPs for uric acid were obtained from BioBank Japan, SNPs for gout were obtained from UK Biobank, and SNPs for gout due to impairment of renal function and idiopathic gout were derived from FinnGen. The causal relationship of exposure-outcome was tested using inverse variance weighted, MR-Egger and weighted median. MR-Egger intercept was employed to assess horizontal pleiotropy, Cochran’s Q test was used to assess heterogeneity, and leave-one-out sensitivity analysis was utilized to analyze the stability of the results.ResultsThe results of MR analysis showed that tea intake was negatively associated with gout due to impairment of renal function (OR 0.997, 95% CI 0.994 to 0.999, P = 0.017), whereas there was no causal association with gout, idiopathic gout, and uric acid (P > 0.05), for which sensitivity analysis suggested that these results were robust.ConclusionsThere was a genetic predisposition effect of increased tea intake on the reduced risk of gout due to impairment of renal function, whereas there was no such effect on gout, idiopathic gout, and uric acid. Tea intake may become an important option in the dietary treatment of gout due to impairment of renal function.</p

Image_1_Effect of tea intake on genetic predisposition to gout and uric acid: a Mendelian randomization study.jpg

ObjectiveThe effect of tea on gout and uric acid is still controversial. This study aims to analyze the effect of tea intake on genetic predisposition to gout, idiopathic gout, gout due to impairment of renal function as well as uric acid by Mendelian randomization (MR).MethodsForty independent single nucleotide polymorphisms (SNPs) associated with tea intake were selected from UK Biobank. SNPs for uric acid were obtained from BioBank Japan, SNPs for gout were obtained from UK Biobank, and SNPs for gout due to impairment of renal function and idiopathic gout were derived from FinnGen. The causal relationship of exposure-outcome was tested using inverse variance weighted, MR-Egger and weighted median. MR-Egger intercept was employed to assess horizontal pleiotropy, Cochran’s Q test was used to assess heterogeneity, and leave-one-out sensitivity analysis was utilized to analyze the stability of the results.ResultsThe results of MR analysis showed that tea intake was negatively associated with gout due to impairment of renal function (OR 0.997, 95% CI 0.994 to 0.999, P = 0.017), whereas there was no causal association with gout, idiopathic gout, and uric acid (P > 0.05), for which sensitivity analysis suggested that these results were robust.ConclusionsThere was a genetic predisposition effect of increased tea intake on the reduced risk of gout due to impairment of renal function, whereas there was no such effect on gout, idiopathic gout, and uric acid. Tea intake may become an important option in the dietary treatment of gout due to impairment of renal function.</p

Image_2_Effect of tea intake on genetic predisposition to gout and uric acid: a Mendelian randomization study.jpg

ObjectiveThe effect of tea on gout and uric acid is still controversial. This study aims to analyze the effect of tea intake on genetic predisposition to gout, idiopathic gout, gout due to impairment of renal function as well as uric acid by Mendelian randomization (MR).MethodsForty independent single nucleotide polymorphisms (SNPs) associated with tea intake were selected from UK Biobank. SNPs for uric acid were obtained from BioBank Japan, SNPs for gout were obtained from UK Biobank, and SNPs for gout due to impairment of renal function and idiopathic gout were derived from FinnGen. The causal relationship of exposure-outcome was tested using inverse variance weighted, MR-Egger and weighted median. MR-Egger intercept was employed to assess horizontal pleiotropy, Cochran’s Q test was used to assess heterogeneity, and leave-one-out sensitivity analysis was utilized to analyze the stability of the results.ResultsThe results of MR analysis showed that tea intake was negatively associated with gout due to impairment of renal function (OR 0.997, 95% CI 0.994 to 0.999, P = 0.017), whereas there was no causal association with gout, idiopathic gout, and uric acid (P > 0.05), for which sensitivity analysis suggested that these results were robust.ConclusionsThere was a genetic predisposition effect of increased tea intake on the reduced risk of gout due to impairment of renal function, whereas there was no such effect on gout, idiopathic gout, and uric acid. Tea intake may become an important option in the dietary treatment of gout due to impairment of renal function.</p

Lattice Strain Distributions in Individual Dealloyed Pt–Fe Catalyst Nanoparticles

Lattice strain is considered to play an important role in the oxygen reduction catalysis on Pt-based catalysts. However, so far, direct evidence of the lattice strain in the catalyst nanoparticles has not been achieved. By using aberration-corrected high-resolution transmission electron microscopy combined with image simulations, a unique core–shell structure, that is, a percolated lattice-contracted Pt–Fe alloy core and a Pt-rich surface with a gradient compressive strain, was directly demonstrated within individual dealloyed Pt–Fe nanoparticles and thus provides direct evidence for the strain effect on their enhanced oxygen reduction activity

Sophisticated Construction of Au Islands on Pt–Ni: An Ideal Trimetallic Nanoframe Catalyst

We have developed a priority-related chemical etching method to transfer the starting Pt–Ni polyhedron to a nanoframe. Utilizing the lower electronegativity of Ni in comparison to Au atoms, in conjunction with the galvanic replacement of catalytically active Au to Ni tops, a unique Au island on a Pt–Ni trimetallic nanoframe is achieved. The design strategy is based on the structural priority mechanism of multimetallic nanocrystals during the synthesis and thus can be generalized to other analogous metal–bimetallic nanocrystal combinations (such as Pd and Cu islands on Pt–Ni nanoframes), which is expected to pave the way for the future development of efficient catalysts

Defect-Dominated Shape Recovery of Nanocrystals: A New Strategy for Trimetallic Catalysts

Here we present a shape recovery phenomenon of Pt–Ni bimetallic nanocrystals that is unequivocally attributed to the defect effects. High-resolution electron microscopy revealed the overall process of conversion from concave octahedral Pt₃Ni to regular octahedral Pt₃Ni@Ni upon Ni deposition. Further experiments and theoretical investigations indicated that the intrinsic defect-dominated growth mechanism allows the site-selective nucleation of a third metal around the defects to achieve the sophisticated design of trimetallic Pt₃Ni@M core–shell structures (M = Au, Ag, Cu, Rh). Consideration of geometrical and electronic effects indicated that trimetallic atomic steps in Pt₃Ni@M could serve as reactive sites to significantly improve the catalytic performance, and this was corroborated by several model reactions. The synthesis strategy based on our work paves the way for the atomic-level design of trimetallic catalysts