Rational Design of a Niobium Tellurite Crystal Nb2Te3O11 Exhibiting Good Overall Infrared NLO Performance by Structural Genetic Engineering.

Nonlinear optical (NLO) materials have aroused increasing interest owing to their promising applications in optoelectronic technologies. Herein, we present the synthesis of an acentric niobium tellurite crystal, Nb2Te3O11, extracted via a spontaneous crystallization approach. It adopts a unique three-dimensional (3D) structure constructed by the distorted [TeO3], [TeO4], and [NbO6] fundamental building units. The title compound undergoes incongruent melting at approximately 807 °C. Optical characterizations demonstrate that Nb2Te3O11 possesses an extended transparency window beyond 5 µm, along with a large band gap value of 3.1 eV. Moreover, the as-synthesized Nb2Te3O11 displays an appreciable second-harmonic generation (SHG) response of 2 × KDP and a notable birefringence of 0.11 under 1064 nm for achieving phase-matching. In addition, theoretical calculation investigations suggest that the intriguing optical properties are ascribed to the cooperative effect of three types of NLO-active motifs: [TeO3] pyramids, [TeO4] seesaws, and [NbO6] octahedra. These attributes provide new functional insights into Nb2Te3O11 and enrich the family of NLO crystals in the mid-infrared region.

Ferroelectric Domain Reversal Dynamics in LiNbO3 Optical Superlattice Investigated with a Real-Time Monitoring System.

The optical superlattice structure derived from a periodic poling process endows ferroelectric crystals with tunable optical property regulation, which has become one of the most efficient strategies for fabricating high-efficiency optical devices. Achieving a precise superlattice structure has been the main barrier for preparation of specific optical applications due to the unclear dynamics of domain structure regulation. Herein, a real-time monitoring system for the in situ observation of periodic poling of lithium niobate is established to investigate ferroelectric domain reversal dynamics. The formation of reversed domain nuclei, growth, and expansion of the domain are monitored, which is highly related to domain growth dynamics. The nucleation and growth of domain are discussed combined with the monition of domain reversal and the variation of local electric field distribution along with finite element analysis. An electrode configuration with multiholes is proposed to use the local electric field more efficiently and controllably, which could achieve a higher domain nucleus density with high uniformity. Two-mm-thick periodically poled LiNbO3 crystals with high quality are achieved. A nonlinear light conversion from 1064.2 to 3402.4 nm is realized by the single-resonance optical parameter oscillator with a nonlinear optical efficiency up to 26.2%.

New advances in clinical application of neostigmine: no longer focusing solely on increasing skeletal muscle strength.

Neostigmine is a clinical cholinesterase inhibitor, that is, commonly used to enhance the function of the cholinergic neuromuscular junction. Recent studies have shown that neostigmine regulates the immune-inflammatory response through the cholinergic anti-inflammatory pathway, affecting perioperative neurocognitive function. This article reviews the relevant research evidence over the past 20 years, intending to provide new perspectives and strategies for the clinical application of neostigmine.

Nanotextured silk fibroin/hydroxyapatite biomimetic bilayer tough structure regulated osteogenic/chondrogenic differentiation of mesenchymal stem cells for osteochondral repair.

OBJECTIVES: Articular cartilage plays a vital role in bearing and buffering. Injured cartilage and subchondral bone repair is a crucial challenge in cartilage tissue engineering due to the peculiar structure of osteochondral unit and the requirement of osteogenic/chondrogenic bi-directional differentiation. Based on the bionics principle, a nanotextured silk fibroin (SF)-chondroitin sulphate (CS)/hydroxyapatite (HAp) nanowire tough bilayer structure was prepared for osteochondral repair. METHODS: The SF-CS/HAp membrane was constructed by alcohol-induced ß-sheet formation serving as the physical crosslink. Its osteochondral repairing capacity was evaluated by culturing bone marrow mesenchymal stem cells (BMSCs) in vitro and constructing a rat osteochondral defect model in vivo. RESULTS: The bilayer SF-CS/HAp membrane with satisfactory mechanical properties similar to natural cartilage imitated the natural osteochondral unit structural layers and exerted the function of bearing and buffering timely after in vivo implantation. SF-CS layer upregulated the expression of chondrogenesis-related genes of BMSCs by surface nanotopography and sustained release CS. Meanwhile, nanotextured HAp layer assembled with nanowire endowed the membrane with an osteogenic differentiation tendency for BMSCs. In vivo results proved that the biomimetic bilayer structure dramatically promoted new cartilage formation and subchondral bone remodelling for osteochondral defect model after implantation. CONCLUSIONS: The SF-CS/HAp biomimetic bilayer membrane provides a promising strategy for precise osteochondral repair.

Histopathology mapping of biochemical changes in diffuse axonal injury by FTIR micro-spectroscopy.

The diagnosis of diffuse axonal injury (DAI) is an important task in forensic pathology and clinical medicine. This study aimed to explore the use of Fourier transform infrared spectroscopy (FTIR) to detect DAI. The DAI area of the rat model was detected point by point by the FTIR-mapping system. Infrared spectral data of DAI were obtained by selecting the amide A band, CH3 symmetric stretching, collagen triple-helix structure and asymmetric stretching vibrational frequency of nucleic acid and phospholipid PO2 as the target peak positions. The system can automatically draw infrared spectral color pathological images. In the DAI group, the amide A protein secondary amine N-H stretching vibration and the collagen triple-helix structure of the high-absorption area were consistent with the DAI area confirmed by the silver and ß-APP staining. The CH3 symmetric stretching, nucleic acid and phospholipid PO2 symmetric stretching vibration absorption spectra showed no significant differences between the experimental and verification groups. The FTIR-mapping technique can visually express the molecular characteristics of DAI, which is expected to be applied to the pathological diagnosis of DAI.

Bio-inspired synthesis of mesoporous HfO2 nanoframes as reactors for piezotronic polymerization and Suzuki coupling reactions.

Complex nanostructures with high compositional and structural tailorability are highly desired in order to meet the material needs in the rapid development of nanoscience and nanotechnology. Therefore, the synthetic technique is of essential importance but currently still suffers from many challenges. Herein, we elaborately explore and demonstrate the flexibility of the anisotropic metallo-organic compound (dihafnium dichloride, Cp2HfCl2) for the fabrication of inorganic architectures by mimicking the assembly behaviors in biomolecules. The open and discrete architectures of mesoporous HfO2 nanoframes were constructed via the self-assembly of precursor with acetone as solvent and ammonia as the basic source, but without any addition of auxiliary organic molecules, like surfactants, DAN or peptides. In addition, the nanostructures (hollow spheres, solid spheres, yolk-shells, aggregations and defect-rich nanoparticles) of HfO2 assemblies can be well manipulated by simply modulating the synthesis parameters. The marked difference in the chemical bonds by the different ligands resulted in discrepant hydrolysis and then specific directional bonds for the diversity of the resultant HfO2 assemblies. Interestingly, the HfO2 nanoframe exhibits enhanced piezoelectricity, and can be used as a microelectrode reactor to trigger the pseudo-electrochemical aniline polymerization reaction by introducing ultrasonic excitation to renew the surface charges. Moreover, as compared with nanoparticle catalysts, the palladium (Pd) loaded nanoframe reactor exhibits obvious enhanced catalytic performance for classical Suzuki coupling, benefiting from the structural advantages of the HfO2 frame. Our findings here can be expected to offer new perspectives to find suitable materials by understanding the analogy between materials chemistry and biomolecule chemistry.

Regulation of transforming growth factor ß-mediated epithelial-mesenchymal transition of lens epithelial cells by c-Src kinase under high glucose conditions.

Recent studies have reported that high glucose (HG) conditions may contribute to the acceleration of renal cell apoptosis and renal fibrosis by inducing epithelial-mesenchymal transition (EMT) of tubular epithelial cells, in which c-Src kinase and transforming growth factor (TGF)-ß are key modulators. In the present study, the roles of c-Src kinase and TGF-ß in EMT of lens epithelial cells (LECs) under HG conditions were investigated. Results indicated human lens epithelial B3 (HLE-B3) cells under HG conditions exhibited significantly increased protein expression levels of phosphorylated c-Src (p-Src418) (P<0.05) and secreted a significantly increased amount of TGF-ß compared with HLE-B3 cells under normal glucose conditions (P<0.05). Notably the c-Src inhibitor PP1 and the activin receptor-like kinase 5 (ALK5) inhibitor SB431542 suppressed EMT of HLE-B3 cells. Results indicated that PP1 significantly inhibited the activities of c-Src and ALK5 and the secretion of TGF-ß, whereas SB431542 only significantly downregulated the protein expression levels and secretion of TGF-ß (P<0.05). Following c-Src knockdown, the protein expression levels of p-Src418, ALK5 and TGF-ß were significantly decreased, the secretion of TGF-ß was significantly suppressed (both P<0.05) and EMT was decreased in HLE-B3 cells. These results suggest that c-Src and TGF-ß may promote EMT of LECs under HG conditions, with c-Src as the upstream regulatory molecule. Thus, the signal axis of c-Src/TGF-ß in EMT of LECs may be a potential novel therapeutic target for the prevention of diabetic subcapsular cataract.

Deposition-precipitation preparation of Ag/Ag3PO4/WO3 nanocomposites for efficient Visible-light degradation of rhodamine B under strongly acidic/alkaline conditions.

A series of novel visible-light-driven Ag/Ag3PO4/WO3 (AAPW) Z-scheme heterostructures were fabricated using a facile deposition-precipitation method followed by photo-reduction without adding any surfactant. To explore more deeply about the photocatalytic activity of AAPW nanocomposites under neutral and strongly acidic/alkaline conditions, we investigated their photocatalytic rhodamine B (RhB) efficiency at different pH value that was controlled by adding HNO3 or NaOH aqueous solution. It was found that as-prepared AAPW photocatalysts showed enhanced photocatalytic RhB efficiency under neutral and even strongly acidic/alkaline environment. The process of charge carrier separation and transfer in the AAPW nanocomposites and Z-scheme mechanism for RhB degradation were described in sufficient detail based on systematical characterizations and measurements. The silver particles introduced to build AAPW Z-scheme structure should contribute to more efficient charge separation, resulting in enhanced photocurrent response and photocatalytic activity. We expect thatthis work will provide systematic study concerning Z-scheme Ag/Ag3PO4/WO3 structure, and fulfill the research about photodegrade activity of catalyst under strongly acidic/alkaline conditions.

Ultrathin N-Doped Mo2C Nanosheets with Exposed Active Sites as Efficient Electrocatalyst for Hydrogen Evolution Reactions.

Probing competent electrocatalysts for hydrogen evolution reaction (HER) of water splitting is one of the most hopeful approaches to confront the energy and environmental crisis. Herein, we highlight ultrathin N-doped Mo2C nanosheets (N-Mo2C NSs) in the role of greatly efficient platinum-free-based electrocatalysts for the HER. The transformation of crystal phase and structure between MoO2 nanosheets with a thickness of ∼1.1 nm and N-Mo2C NSs with a thickness of ∼1.0 nm is studied in detail. Structural analyses make clear that the surfaces of the N-Mo2C NSs are absolutely encompassed by apical Mo atoms, hence affording an ideal catalyst prototype to expose the role of Mo atoms for the duration of HER catalysis. Theoretical calculations demonstrate that the nanosheet structure, N doping, and particular crystalline phase of Mo2C produce more exposed Mo active sites, including Mo atoms on the C plane and doped N atoms. Through detailed electrochemical investigations, N-Mo2C NSs possess HER activity with an onset potential of -48.3 mV vs RHE, Tafel slope of 44.5 mV dec-1, and overpotential of 99 mV vs RHE at the cathodic current density of 10 mA cm-2 with excellent long-term stability. Lastly, the calcination temperature and dicyandiamide amount can obviously affect the phase transformation and surface structure of molybdenum carbide, resulting in an adjustable HER activity. This synthesis mechanism will facilitate the understanding and optimization of Mo-based electrocatalysts in the energy conversion field.

Study on efficacy and visual sensitivity of long-term masking therapy for children with ametropic amblyopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the efficacy and visual sensitivity of occlusion therapy combined training for children with ametropic amblyopia.METHODS:Totally 85 children (85 eyes) with anisometropic amblyopia treated in our hospital from January 2013 to January 2015 were selected.All patients were given occlusion therapy combined training.Statistical analysis of clinical efficacy and visual sensitivity changes were taken,and the changes of visual acuity,AULCSF,S Frmax were analyzed.RESULTS:The visual acuity after therapy was significantly better than that before treatment (1.12±0.29 vs0.45±0.25,P＜0.01);AULCSF,Smax and Frmax all increased,the difference between the two groups was statistically significant (P＜ 0.05).The sensitivity of the same spatial frequency was significantly higher than that before treatment,the difference was statistically significant (P ＜ 0.05),and the contrast sensitivity decreased gradually with the increase of spatial frequency.There were statistical differences in the total effective rate of different refractive degrees after treatment (P=0.001).Mild group and moderate group had no significant difference on the total clinical efficiency difference (x2=3.091,P=0.079);between mild group and severe group total effective rate was significantly different (x2 =11.471,P =0.001);the moderate and severe groups total clinical efficiency were no significantly different (x2 =3.359,P=0.067).In addition,the total efficiency rate of wearing glasses under the age of 6 was significantly higher than that after 6 years old (95％ vs 77％),statistical difference between the two groups was significant (P＜0.05).CONCLUSION:Masking therapy combined with comprehensive training,in the treatment of children with ametropic amblyopia,and wearing a corrective spectacles,is desirable,especially for children under 7 years of age.