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Background A birth population-based study was conducted in Danyang, Jiangsu Province, to evaluate major birth defects in emerging regions in China with similar maternal and neonatal care conditions. Methods We conducted a population-based study in a cohort of infants born in Danyang from 2014 to 2021, including 55 709 perinatal infants. Four categories of isolated birth defects were defined as cases: congenital heart defects (CHDs; n=2138), polydactyly (n=145), cleft lip with or without palate (CL/P; n=76) and accessory auricles (n=93). Infants with congenital malformations were identified by the Chinese Birth Defects Monitoring Network. Results Compared with autumn, conception in spring (OR=1.31 [1.16–1.48]) and winter (OR=1.39 [1.23–1.58]) was associated with an increased risk of CHD. Increased risk of CHD, CL/P and accessory auricles was significantly associated with non-local registered residence (OR=1.17 [1.07–1.28], OR=2.73 [1.52–4.88] and OR=2.11 [1.20–3.71], respectively). Individuals of Han nationality were less likely to have polydactyly (OR=0.23 [0.05–0.98]). Conclusions The season of pregnancy was significantly associated with CHDs. Offspring of mothers with non-local registered hometown had greater risks of CHDs, CL/P and accessory auricles. [ABSTRACT FROM AUTHOR]

In alkali metal‐doped optical temperature measurement materials, the influence of the electronegativity difference of alkali metal ions on optical temperature measurement performance is rarely reported. This study investigates and analyzes the performance of optical temperature measurement of Na0.5Gd0.5TiO3: Yb, Er doped with Li+ and K+ ions, utilizing the Judd‐Ofelt theory and the first‐principles method. The results reveal that the sensitivities increase with the increase of atomic number of doped alkali metal ions. The reason is that a difference in ionic radius between the dopant and the replaced ion decreases the symmetry of the crystal field and increases the value of Ω2. The doping K+ with low electronegativity leads to an increase in the s orbital electron density of rare earth ions, thereby repelling the d orbital electrons, reducing the d electron density, and decreasing the value of Ω6. Based on the Judd‐Ofelt theory, a combination of a large Ω2 and a small Ω6 is expected to enhance the absolute sensitivity of optical temperature‐measuring materials doped with rare earth ions. Therefore, it can be concluded that doping an ion with low electronegativity and a significant radius difference from the substitution site is beneficial for enhancing the optical temperature sensitivity. [ABSTRACT FROM AUTHOR]

In the search for high-stiffness and damage-tolerant materials, Fe-based A 3 BX carbide and nitride anti-perovskites were studied using first-principles calculations. These perovskites were found to be stable in cubic structures, as substantiated by the formation energy, elastic Born stability criterion, and phonon dispersion spectrum analysis. The GGA functional was applied for geometry optimization, and the lattice constants are found to be 3.730 Å, 3.715 Å, 3.832 Å, and 3.828 Å for Fe 3 AlC, Fe 3 AlN, Fe 3 SnC, and Fe 3 SnN, respectively. Elastic property analysis reveals that all the materials have large elastic moduli, high sound velocities, and high Debye temperatures. Among them, carbides have superior stiffness and quasi-ductile properties, and they can be further improved by applying additional pressure. Preliminary analysis of electronic properties indicates that they are ferromagnetic and metallic compounds. Their high melting temperatures (>2600 K) confirm their potential in high-temperature applications. The lowest thermal conductivity of Fe 3 SnN suggests its potential in efficient solid-state refrigeration application. Moreover, Fe 3 SnC is proposed to be a viable damage-tolerant material with good prospects. Under 10 GPa external pressure, it possesses a ductile structure with a Young's modulus of 402.15 GPa and bulk modulus of 280.25 GPa.