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Herein, a YAG/10 at% Yb:YAG/YAG transparent ceramic planar waveguide (PWG) gain medium has been molded via inkjet printing and dry pressing molding. The composition and rheological property of ink are optimized along with the printing process to enhance the printing accuracy and quality. The PWG has dimensions of 13.5 × 8.0 × 1.8 mm3, while the thickness of the core Yb:YAG layer is ≈190 μm. The in‐line transmittance of the PWG reaches 81.7% at 1030 nm, and the average grain size is ≈2.3 μm. The diffusion characteristics of Yb ions across the interface between the cladding YAG layer and the core Yb:YAG layer are investigated by calculating the diffusion coefficient and the mean diffusion distance of 172Yb ions. The Yb:YAG PWG oscillator, which is pumped from a single end by a 940 nm laser diode, produces continuous wave laser at a wavelength of 1030 nm and exhibits the highest power (3.8 W) and highest absorbed–output slope efficiency (64.6%). [ABSTRACT FROM AUTHOR]

Marbach‐Rustad progeroid syndrome is an extremely rare disease caused by a heterozygous variant in the LEMD2 gene. To date, only two patients and one LEMD2 pathogenic variant have been reported in Marbach‐Rustad progeroid syndrome. Here we describe the third case of Marbach‐Rustad progeroid syndrome worldwide, which is also the first case in China. The proband was affected with premature birth, failed to thrive, facial abnormalities, feeding difficulties, skull defects and delayed motor milestones, but had a normal intelligence and speech. Whole exome sequencing (WES) initially did not find a phenotype‐causing variant when the proband was 1 year of age. The reanalysis of WES data 4 years later revealed the proband harbored a de novo heterozygous c.1436C>T(p.Ser479Phe) variant in the LEMD2 gene, which is known responsible for Marbach‐Rustad progeroid syndrome. Sanger sequencing confirmed the presence of this variant in the proband and absence in his parents and two elder sisters. Our study provides accurate clinical diagnosis for the proband and adds a new patient with Marbach‐Rustad progeroid syndrome. Our study suggests the LEMD2 c.1436C>T(p.Ser479Phe) variant as a hotspot. Our work also indicates reanalysis of WES data of negative cases might identify pathogenic variant and improve diagnostic efficiency. [ABSTRACT FROM AUTHOR]

Photochromic (PC) materials can be widely applied in light‐driven devices such as optical antifake labels, optical switches, information storage. Herein, Er3+ and Pr3+ co‐doped Na0.5+xBi2.5+xNb2O9 (x = −0.02, 0, 0.02) ferroelectric ceramics with excellent PC and luminescence modulation properties have been successfully prepared. Both chemical and physical strategies, namely excess Na+ and Bi3+ content during weighing of raw materials and an electric field poling, have been developed to enhance the PC and luminescence modulation. The largest reflectance difference ΔRef between fresh and irradiated ceramics reaches a high value of 36% at x = 0.02, which is much higher than the usually obtained value in inorganic oxide ferroelectrics. Additionally, this value increases to 39% after an electric field poling. Accordingly, the up‐conversion luminescence modulation ΔRt reaches a high value of 91.6%. The mechanisms of enhanced PC reaction and luminescence modulation via an electrical poling are discussed. Furthermore, a fast response time of around 1 s for PC reaction is achieved in this material. Utilizing this advantage, a hand‐rewritable display using the prepared ceramics has been achieved besides the applications in anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

In this study, fine Y2O3–MgO composite nanopowders were synthesized via the sol–gel method. Dense Y2O3–MgO composite ceramics were fabricated by pre‐sintering the green body in air at different temperatures for 1 h and then subjecting the sintered bodies to hot isostatic pressing at 1300°C for 1 h. The effects of pre‐sintering temperature on the microstructural, mechanical, and optical properties of the resulting ceramics were studied. The average grain size of the ceramics was increased, whereas their hardness and fracture toughness were decreased with increasing pre‐sintering temperature. A maximum fracture toughness of 1.42 MPa·m1/2 and Vickers hardness of 10.4 GPa were obtained. The average flexural strength of the ceramics was 411 MPa at room temperature and reached 361 MPa at 600°C. A transmittance of 84% in the 3–5 µm region was obtained when the composite ceramics were sintered at 1400°C. Moreover, a transmittance of 76% in the 3–5 µm region was obtained at 500°C. [ABSTRACT FROM AUTHOR]

In this study, highly transparent aluminate oxynitride (AlON) ceramics were prepared via the reactive sintering of Al2O3 and AlN powders using a Y2O3‐MgAl2O4‐H3BO3 ternary sintering additive. The ternary doping process resulted in the efficient preparation of transparent AlON ceramics with small grains and high transmittance as compared to the binary doping (Y2O3‐MgAl2O4) process. The addition of 0.1 wt.% Y2O3‐0.4 wt.% MgAl2O4‐0.12 wt.% H3BO3 resulted in the formation of a 4‐mm‐thick AlON ceramic with high transmittance (81% at 600 nm) and low haze (3.46%). This is the best performance in terms of the thickness and transmittance reported for AlON transparent ceramics prepared by the reactive sintering method. [ABSTRACT FROM AUTHOR]

The oxidation behavior and mechanism of aluminum oxynitride (AlON) powder exposed to air at elevated temperatures between 800°C and 1300°C was investigated by X‐ray diffractometry (XRD), scanning electron microscope (SEM), electron spin resonance (ESR), nuclear magnetic resonance (NMR), and simultaneous thermogravimetry, differential thermal analysis, and mass spectrometry techniques (TG‐DTA‐MS). The weight of AlON gradually increases to a maximum value at 1150°C and then decreases with further heating. Meanwhile, AlON powder undergoes chemical changes, as evidenced by lattice expansion, and turns eventually into alumina. ESR spectra reveal the occurrence of lone pair electrons in the oxidized products and the intensity of corresponding resonance signal increases before disappearing with the increase in temperature. Combined with the results of NMR and TG‐DTA‐MS, the measured data suggest that Al‐N in [AlO3N] tetrahedron and [AlO5N] octahedron are gradually oxidized into Al‐O‐N group with lone pair electrons, which causes continuous weight gain and lattice expansion. Further oxidation at higher temperatures results in alumina and N2. [ABSTRACT FROM AUTHOR]

This study reports a new wet forming method by hydrophobic modification of short‐chain anionic dispersants. The influence of the content and type of hydrophobic chains on the rheology of alumina slurries, the drying shrinkage rates of wet bodies, the density and strength of the green bodies, and the density and microstructure of the resultant ceramics were intensively investigated. It is revealed that hydrophobic modification can endow short‐chain dispersants with coagulation ability, when 0.3 wt% short‐chain PIBM (a copolymer of isobutylene and maleic anhydride) was combined with 0.1 wt% TMAC (tetramethylammonium chloride), solid loading of the slurry was increased to 58 vol% and the slurry can coagulate to a wet green body in a short time. The resultant green body showed a uniform microstructure and was successfully sintered into translucent ceramics. [ABSTRACT FROM AUTHOR]

Highly transparent Y2O3 ceramics using TiO2 as an additive were synthesized by presintering and hot isostatic pressing (HIP). The effects of TiO2 contents and sintering conditions on the optical properties of the final transparent ceramics were investigated. A small amount (0.04‐0.16 wt%) may decrease the densification temperature by about 200°C. The Y2O3 ceramics doped with 0.16 wt% TiO2 revealed a transparency of 82% in the wavelength range 1‐6 μm. The thermal conductivity of the samples is about 11.8 W/m K at 25°C, which is close to that of the undoped Y2O3 ceramics. [ABSTRACT FROM AUTHOR]

Transparent glass-ceramics containing Er3+:CaF2 crystallites were prepared with the co-firing method. The formation process of the glass-ceramics was investigated by means of SEM, XRD, and DSC. The results reveal that the Er3+:CaF2 nanocrystals do not dissolve into the fluorophosphates ( FP) glassmelt until the co-firing temperature increase higher than about 920°C. Below this temperature, Er3+:CaF2 survives the co-firing process and the nanocrystals just grow to spherical crystals of micrometers in size. Co-firing temperature higher than this temperature leads to the dissolution of Er3+:CaF2 and the dissolved Er3+:CaF2 recrystallized during quenching process and takes the shape of dendrite. [ABSTRACT FROM AUTHOR]

Strontium fluorapatite particles with tunable morphologies and geometries were successfully synthesized via a precipitation system by adjusting the pH value and temperature. Several analysis techniques were used to investigate and characterize the particles. The surface energy was calculated using first-principle calculations based on density functional theory. Capsule-like nanosized primary grains with axial growth directions parallel to the c-axis were synthesized at higher pH values, resulting from the difference in surface energy for the different planes of the Sr5( PO4)3F lattice. Bundle-like clusters were obtained at a pH value of ~7, which was attributed to a combination of the difference in surface energy and the phenomenon of heterogeneous nucleation occurring at low degrees of supersaturation. The study determined the approaches necessary to manufacture Sr5( PO4)3F powders with specific characteristics for different applications. [ABSTRACT FROM AUTHOR]

Context Affected by steroid 5α-reductase type 2 deficiency (5α- RD2), 46, XY individuals present divergent phenotypes characterized by undervirilization of male external genitalia. To identify the disorder, mutational analysis of 5α-reductase type 2 gene ( SRD5A2) is a reliable approach. The genotype-phenotype relationship has not been elucidated. Objective To improve the diagnosis and expand the knowledge of the disease, we collected and analysed relevant data of clinical diagnosis, biological investigation and molecular determination in 45 children with the SRD5 A2 gene mutations from South China in our centre. Subjects and methods We studied a cohort of 45 Chinese children with SRD5 A2 gene mutations. Results Isolated microphallus (35·6%) and microphallus associated with various degrees of hypospadias (55·6%) were frequent phenotype. Female external genitalia with clitoromegaly (8·9%) were rare. 16 of 18 (88·9%) cases had hCG-stimulated T/ DHT ratio above 10. In 45 patients, we identified 15 different mutations. Five have never been described: p. His90 Thrfs X31, p. Gly21 Arg, p. Gly149 Asp, p. Arg145 Leu and p. Gly66 Arg. The p. Arg227 Gln mutation was detected in 41 (91·1%) patients. The p. Leu89 Val polymorphism was found in 38 (84·4%) patients. Homozygous mutations were presented in 16 (35·6%) patients, compound heterozygous mutations in 20 (44·4%) patients, compound heterozygous mutations alone with the p. Leu89 Val polymorphism in nine (20·0%) patients. Exons 1 and 4 were most affected, and the number of mutant alleles per exon was 78·1% and 12·2%, respectively. Conclusions The study demonstrated a wide spectrum of phenotypes, biological profiles and genotypes in the children with 5α- RD2 from South China. The heterozygous mutation p. Arg227 Gln is presumably a hot spot mutation and suggests a founder effect in the population of South China that may explain a moderate phenotype among our patients. Our report provides new insights into the molecular mechanism of 5α- RD2 and help to the diagnosis and treatment of this disease. [ABSTRACT FROM AUTHOR]