Alterations in the gut microbiota may influence gastrointestinal (GI) dysbiosis frequently reported in individuals with autism spectrum disorder (ASD). In this study, we sequenced the bacterial 16S rRNA gene to evaluate changes in fecal microbiota between 48 children with ASD and 48 healthy children in China. At the phylum level, the number of Firmicutes, Proteobacteria, and Verrucomicrobia decreased in children with ASD, while the Bacteroidetes/Firmicutes was significantly higher in autistic children due to enrichment of Bacteroidetes. At the genus level, the amount of Bacteroides, Prevotella, Lachnospiracea_incertae_sedis, and Megamonas increased, while Clostridium XlVa, Eisenbergiella, Clostridium IV, Flavonifractor, Escherichia/Shigella, Haemophilus, Akkermansia, and Dialister decreased in children with ASD relative to the controls. Significant increase was observed in the number of species synthesizing branched‐chain amino acids (BCAAs), like Bacteroides vulgatus and Prevotella copri, while the numbers of Bacteroides fragilis and Akkermansia muciniphila decreased in children with ASD compared to the controls. Most importantly, the highest levels of pathogenic bacteria were different for each child with ASD in this cohort. We found that only one functional module, cellular antigens, was enriched in children with ASD, and other pathways like lysine degradation and tryptophan metabolism were significantly decreased in children with ASD. These findings provide further evidence of altered gut microbiota in Chinese ASD children and may contribute to the treatment of patients with ASD. Lay Summary This study characterized the gut bacteria composition of 48 children with ASD and 48 neurotypical children in China. The metabolic disruptions caused by altered gut microbiota may contribute significantly to the neurological pathophysiology of ASD, including significant increases in the number of species synthesizing BCAAs, and decreases in the number of probiotic species. These findings suggest that a gut microbiome‐associated therapeutic intervention may provide a novel strategy for treating GI symptoms frequently seen in individuals with ASD. Autism Res 2020, 13: 1614–1625. © 2020 International Society for Autism Research, Wiley Periodicals, Inc.

Multiferroic materials, which offer the possibility of manipulating the magnetic state by an electric field or vice versa, are of great current interest. However, single-phase materials with such cross-coupling properties at room temperature exist rarely in nature; new design of nano-engineered thin films with a strong magneto-electric coupling is a fundamental challenge. Here we demonstrate a robust room-temperature magneto-electric coupling in a bismuth-layer-structured ferroelectric Bi5Ti3FeO15 with high ferroelectric Curie temperature of ~1000 K. Bi5Ti3FeO15 thin films grown by pulsed laser deposition are single-phase layered perovskit with nearly (00l)-orientation. Room-temperature multiferroic behavior is demonstrated by a large modulation in magneto-polarization and magneto-dielectric responses. Local structural characterizations by transmission electron microscopy and Mössbauer spectroscopy reveal the existence of Fe-rich nanodomains, which cause a short-range magnetic ordering at ~620 K. In Bi5Ti3FeO15 with a stable ferroelectric order, the spin canting of magnetic-ion-based nanodomains via the Dzyaloshinskii-Moriya interaction might yield a robust magneto-electric coupling of ~400 mV/Oe·cm even at room temperature.

A lead-free piezoelectric material with ultra-high properties, Ba(Ti0.8Zr0.2)O3-x(Ba0.7Ca0.3)TiO3(BZTxBCT) nanocrystals was synthesized via a sol-gel method, and the corresponding thin films were also deposited on Pt/Ti/SiO2/Si substrates by a spin-coating approach. The BZT-xBCT thin film exhibited a high remnant polarization of 22.15 mC cm2 with a large coercive field of 68.06 kV cm1. The resultant gel is calcined at various elevated temperatures and studied with FTIR/XRD/Raman/DSC-TGA/AFM/SEM techniques for gel composition, crystallization, phase transition, thermochemistry and the morphology of the film. Although the room temperature crystal structure of the BZT-xBCT nanocrystals appears to be a standard perovskite structure by conventional X-ray diffraction (XRD), Raman spectroscopy demonstrates the presence of non-centrosymmetric regions arising from the off-centering of the titanium (zirconium) atoms.The Raman spectra findings demonstrate the degree by which the tetragonal phase grows with the increase of calcining temperature in BZT-0.5BCT, and the characteristic ferroelectric-ferroelectric phase transition in BZT-xBCT while going through the MPB process. The structural and constituent evolution for the conversion process from gel to ceramic, as well as the formation mechanism of the BZT-0.5BCT crystallite, were also elucidated.Keywords gel, synthesized, ba, ti0, 8zr0, 2, crystallization, o3, ferroelectric, x, ba0, 7ca0, 3, tio3, thin, films, evolution, phase, properties, sol Disciplines Engineering | Physical Sciences and Mathematics Publication DetailsWang, Z., Zhao, K., Guo, X., Sun, W., Jiang, H., Han, X., Tao, X., Cheng, Z., Zhao, H., Kimura, H., Yuan, G., Yin, J. & Liu, Z. (2013). Crystallization, phase evolution and ferroelectric properties of sol-gel-synthesized Ba(Ti0.8Zr0.2)O3-x(Ba0.7Ca0.3)TiO3 thin films. Journal of Materials Chemistry C, 1 522-530. AuthorsZeng-mei Wang, Kuan Zhao, Xin-li Guo, Wei Sun, Hua-long Jiang, Xue-qin Han, Xu-tang Tao, Zhen-xiang Cheng, Hong-yang Zhao, Hideo Kimura, Guo-liang Yuan, Jiang Yin, and Zhi-guo Liu nanocrystals was synthesized via a sol-gel method, and the corresponding thin films were also deposited on Pt/Ti/SiO 2 /Si substrates by a spin-coating approach. The BZT-xBCT thin film exhibited a high remnant polarization of 22.15 mC cm À2 with a large coercive field of 68.06 kV cm À1 . The resultant gel is calcined at various elevated temperatures and studied with FTIR/XRD/Raman/DSC-TGA/AFM/SEM techniques for gel composition, crystallization, phase transition, thermochemistry and the morphology of the film. Although the room temperature crystal structure of the BZT-xBCT nanocrystals appears to be a standard perovskite structure by conventional X-ray diffraction (XRD), Raman spectroscopy demonstrates the presence of non-centrosymmetric regions arising from the off-centering of the titanium (zirconium) atoms. The Raman spectra findings demonstrate the degree by which the tetragonal phase grows with the increase of calcining temperature in BZT-0.5BCT, and the...

the emerging global energy crisis. [1] To boost the hydrogen production efficiency, the rational design and fabrication of semiconductor photoelectrodes with broad light absorption, adequate exciton generation, efficient charge separation/transfer, and long-term stability are highly desired. [2] Recently, semiconductors quantum dots (QDs) have demonstrated huge potential as light sensitizers in photoanodes for high efficiency solar-driven PEC application due to their size/shape/composition-tunable optical properties that features considerable overlap with solar spectrum. [3] However, the state-of-the-art QDs used in current PEC systems still suffer from major limitations including highly toxic heavy metal elements (Pb, Cd etc.), insufficient charge separation/transfer, and low photo-stability. [1b,4] Developing eco-friendly core/shell structured QDs is a promising strategy to address these issues, while a proper selection of core and shell materials is necessary to obtain core/shell QDs with tailored band structure, optimized optical properties/ charge dynamics, and enhanced photo/chemical stability for high performance and stable solar-to-hydrogen conversion.Among various semiconductor QDs, heavy metal-free InP QDs have recently attracted great attention due to their large absorption coefficient, narrow band gap (≈1.34 eV in bulk), and wide wavelength tunability. [5] Nevertheless, bare InP QDs can exhibit abundant surface defect states, resulting in severe non-radiative recombination for largely reduced quantum yield (QY, usually <5%) and photo/chemical stability. [6] Generally, inorganic shell (such as ZnS and ZnSe) were coated on InP core QDs to form type I band alignment with improved radiative emission and photo/chemical stability. [7] Considering the stress-induced defects at the core/shell interface, the ZnSe shell with a lower lattice mismatch (3.4%) as compared to ZnS (7.6%) is more appropriate to coat on InP core for optimized optical characteristics. [8] In 2019, Jang et al. synthesized InP/ZnSe/ZnS QDs to fabricate a red QDs-light-emitting diode (QLED) with an external quantum efficiency of 21.4%, which is considered as a milestone for the display application based on environmentally friendly QDs, demonstrating the huge potential of InP-based core/shell QDs as building blocks in optoelectronic devices. [9] However, to date, most of the investigations regarding InP-based core-shell QDs are mainly focused on enhancing As emerging eco-friendly alternatives to traditional Cd/Pb-based quantum dots (QDs), InP/ZnSe(S) core/shell QDs have demonstrated huge potential in light-emitting technologies. So far, these QDs have been rarely employed in solar energy conversion applications due to their type-I band structure offering limited photo-induced charge carrier separation and transfer. Here, a controllable Cu shell doping approach is reported to engineer the optoelectronic properties of InP/ZnSe core/shell QDs and realize high performance and stable solar-driven photoelectrochemical (PEC) hydrogen evol...

A state-of-the-art spherical aberration-corrected STEM was fully utilized to directly visualize the multiferroic domain structure in a hexagonal YMnO3 single crystal at atomic scale. With the aid of multivariate statistical analysis (MSA), we obtained unbiased and quantitative maps of ferroelectric domain structures with atomic resolution. Such a statistical image analysis of the transition region between opposite polarizations has confirmed atomically sharp transitions of ferroelectric polarization both in antiparallel (uncharged) and tail-to-tail 180° (charged) domain boundaries. Through the analysis, a correlated subatomic image shift of Mn-O layers with that of Y layers, exhibiting a double-arc shape of reversed curvatures, have been elucidated. The amount of image shift in Mn-O layers along the c-axis is statistically significant as small as 0.016 nm, roughly one-third of the evident image shift of 0.048 nm in Y layers. Interestingly, a careful analysis has shown that such a subatomic image shift in Mn-O layers vanishes at the tail-to-tail 180° domain boundaries. Furthermore, taking advantage of the annular bright field (ABF) imaging technique combined with MSA, the tilting of MnO5 bipyramids, the very core mechanism of multiferroicity of the material, is evaluated.

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The structure and magnetic properties of perovskite DyMn1−xFexO3 samples have been studied. Static orbital orderings are expected to exist in samples with x ≤ 0.2 due to strong Jahn-Teller distortion, which become less stable as x increases and probably disappears in samples with x &gt; 0.5. The antiferromagnetic transition temperature increases as x increases. At the composition x &gt; 0.5, spin reorientation starts to appear. Meanwhile, the spin reorientation temperature and the antiferromagnetic Néel temperature gradually separate and widen the temperature range of the magnetic metastable state between these two transitions. The magnetic competition is discussed based on exchange interaction and Dzyaloshinsky-Moriya interaction.

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