Replication of the Association of a MET Variant with Autism in a Chinese Han Population

Background: Autism is a common, severe and highly heritable neurodevelopmental disorder in children, affecting up to 100 children per 10,000. The MET gene has been regarded as a promising candidate gene for this disorder because it is located within a replicated linkage interval, is involved in pathways affecting the development of the cerebral cortex and cerebellum in ways relevant to autism patients, and has shown significant association signals in previous studies. Principal Findings: Here, we present new ASD patient and control samples from Heilongjiang, China and use them in a case-control and family-based replication study of two MET variants. One SNP, rs38845, was successfully replicated in a case-control association study, but failed to replicate in a family-based study, possibly due to small sample size. The other SNP, rs1858830, failed to replicate in both case-control and family-based studies. Conclusions: This is the first attempt to replicate associations in Chinese autism samples, and our result provides evidence that MET variants may be relevant to autism susceptibility in the Chinese Han population

Perovskite Solar Cells Fabricated by Using an Environmental Friendly Aprotic Polar Additive of 1,3-Dimethyl-2-imidazolidinone

Abstract Perovskite solar cells (PSCs) have great potentials in photovoltaics due to their high power conversion efficiency and low processing cost. PSCs are usually fabricated from PbI2/dimethylformamide solution with some toxic additives, such as N-methyl pyrrolidone and hexamethylphosphoramide. Here, we use an environmental friendly aprotic polar solvent, 1,3-dimethyl-2-imidazolidinone (DMI), to fabricate perovskite films. By adding 10 vol% DMI in the precursor solution, high-quality perovskite films with smooth surface are obtained. By increasing annealing temperature from 100 to 130 °C, the average grain size of the perovskite increases from ~ 216 to 375 nm. As a result, the efficiency of the PSCs increases from 10.72 to 14.54%

Fabrication of Perovskite Films with Large Columnar Grains via Solvent-Mediated Ostwald Ripening for Efficient Inverted Perovskite Solar Cells

Generally, residual solvent is embedded in perovskite precursor films fabricated from the Lewis adduct method. Most of the research focus on the ligand function of the solvent in forming a solvate complex for fabricating high quality perovskite films. However, little attention has been paid to the latent function of the solvent in the perovskite precursor films during the annealing process due to its fast extravasation at high temperature. Here, we develop a sandwich configuration of substrate/perovskite precursor films/PC₆₁BM to retard the extravasation of solvent during annealing. We find that the restrained solvent induces an obvious solvent-mediated dissolution–recrystallization process, leading to high quality perovskite films with large columnar grains. There is mass transportation from small grains to large grains in the dissolution–recrystallization process, which follows the Ostwald ripening model. Inverted planar solar cells are fabricated on the basis of this annealing method. The photovoltaic performance of the solar cells is improved significantly due to its high quality perovskite films with large columnar grains

Elucidating the Key Role of a Lewis Base Solvent in the Formation of Perovskite Films Fabricated from the Lewis Adduct Approach

High-quality perovskite films can be fabricated from Lewis acid–base adducts through molecule exchange. Substantial work is needed to fully understand the formation mechanism of the perovskite films, which helps to further improve their quality. Here, we study the formation of CH₃NH₃PbI₃ perovskite films by introducing some dimethylacetamide into the PbI₂/<i>N</i>,<i>N</i>-dimethylformamide solution. We reveal that there are three key processes during the formation of perovskite films through the Lewis acid–base adduct approach: molecule intercalation of solvent into the PbI₂ lattice, molecule exchange between the solvent and CH₃NH₃I, and dissolution–recrystallization of the perovskite grains during annealing. The Lewis base solvents play multiple functions in the above processes. The properties of the solvent, including Lewis basicity and boiling point, play key roles in forming smooth perovskite films with large grains. We also provide some rules for choosing Lewis base additives to prepare high-quality perovskite films through the Lewis adduct approach

Emulsion Synthesis of Size-Tunable CH₃NH₃PbBr₃ Quantum Dots: An Alternative Route toward Efficient Light-Emitting Diodes

We report a facile nonaqueous emulsion synthesis of colloidal halide perovskite quantum dots by controlled addition of a demulsifier into an emulsion of precursors. The size of resulting CH₃NH₃PbBr₃ quantum dots can be tuned from 2 to 8 nm by varying the amount of demulsifier. Moreover, this emulsion synthesis also allows the purification of these quantum dots by precipitation from the colloidal solution and obtains solid-state powder which can be redissolved for thin film coating and device fabrication. The photoluminescence quantum yields of the quantum dots is generally in the range of 80–92%, and can be well-preserved after purification (∼80%). Green light-emitting diodes fabricated comprising a spin-cast layer of the colloidal CH₃NH₃PbBr₃ quantum dots exhibited maximum current efficiency of 4.5 cd/A, power efficiency of 3.5 lm/W, and external quantum efficiency of 1.1%. This provides an alternative route toward high efficient solution-processed perovskite-based light-emitting diodes. In addition, the emulsion synthesis is versatile and can be extended for the fabrication of inorganic halide perovskite colloidal CsPbBr₃ nanocrystals

Controlled Growth of Ag/Au Bimetallic Nanorods through Kinetics Control

One-dimension noble nanomaterials have promising applications in many fields, and their growth pattern control is significant to property modulation. Herein, we report a facile strategy with which the growth pattern of Ag on the Au nanorod (NR) or decahedral nanoparticle (NP) surface can be precisely controlled and various structured Ag/Au NRs can be synthesized. Achievement of growth pattern control is mainly attributed to the adjustable reaction kinetics of Ag^– to Ag⁰. Slow and moderate reaction rate favor asymmetrical growth, producing Au-tipped Ag NRs and asymmetrical Ag–Au–Ag NRs, respectively. In the case of a fast reaction rate, symmetrical growth dominates and symmetrical Ag–Au–Ag NRs form. Furthermore, the prepared bimetallic NRs can be used as starting materials to generate other novel nanostructures (nanocups, nanonails, and longer Au-tipped Ag NRs). The result presented here is vital to both exploration of growth theory and constructing nanostructures of not only the Au/Ag bimetallic system but also possibly other noble bimetallic systems. Moreover, these prepared nanostructures could provide model materials for studying the physical properties (such as structure-dependent surface plasmon) or have potential applications in the medical field. For example, hollow nanocups can serve as containers for controlled release of drug, etc

Statistical analysis of rs38845 and rs1858830 in the Chinese Han case and control samples.

<p>Statistical analysis of rs38845 and rs1858830 in the Chinese Han case and control samples.</p