Fecal microbiota transplantation for treatment of non-alcoholic fatty liver disease:Mechanism,clinical evidence,and prospect

The population of non-alcoholic fatty liver disease(NAFLD)patients along with relevant advanced liver disease is projected to continue growing,because currently no medications are approved for treatment.Fecal microbiota transplantation(FMT)is believed a novel and promising therapeutic approach based on the concept of the gut-liver axis in liver disease.There has been an increase in the number of pre-clinical and clinical studies evaluating FMT in NAFLD treatment,however,existing findings diverge on its effects.Herein,we briefly summarized the mechanism of FMT for NAFLD treatment,reviewed randomized controlled trials for evaluating its efficacy in NAFLD,and proposed the prospect of future trials on FMT.

Effect of carrier mobility on performance of perovskite solar cells

The high carrier mobility and long diffusion length of perovskite material have been regarded because of its excellent photovoltaic performance. However, many studies have shown that a diffusion length longer than 1 μm and higher carrier mobility have no positive effect on the cells' performance. Studies of organic solar cells have demonstrated the existence of an optimal mobility value, while systematic research of the carrier mobility in the PSCs is very rare. To make these questions clear, the effect of carrier mobility on perovskite solar cells' performance is studied in depth in this paper by simulation.Our study shows that the optimal mobility value of the charge transportation layer and absorption layer are influenced by both doping concentration and layer thickness. The appropriate carrier mobility can reduce the carrier recombination rate and enhance the carrier concentration, thus improving the cells' performance. A high efficiency of 27.39% is obtained in the simulated cell with the combination of the optimized parameters in the paper.

Color liquid crystal grating based color holographic 3D display system with large viewing angle

Holographic 3D display is highly desirable for numerous applications ranging from medical treatments to military affairs.However,it is challenging to simultaneously achieve large viewing angle and high-fidelity color reconstruction due to the intractable constraints of existing technology.Here,we conceptually propose and experimentally demonstrate a simple and feasible pathway of using a well-designed color liquid crystal grating to overcome the inevitable chromatic aberration and enlarge the holographic viewing angle,thus enabling large-viewing-angle and color holographic 3D display.The use of color liquid crystal grating allows performing secondary diffraction modulation on red,green and blue reproduced images simultaneously and extending the viewing angle in the holographic 3D display system.In principle,a chromatic aberration-free hologram generation mechanism in combination with the color liquid crystal grating is proposed to pave the way for on such a superior holographic 3D display.The proposed system shows a color viewing angle of~50.12°,which is about 7 times that of the traditional system with a single spatial light modulator.This work presents a paradigm for achieving desirable holographic 3D display,and is expected to provide a new way for the wide application of holographic display.

变形参数对AZ31B镁合金直齿圆柱齿轮热锻过程中变形和显微组织演变的影响（英文）

应用有限元模拟和统计分析方法研究变形参数对直齿圆柱齿轮成形过程中变形和显微组织演变的影响。将有限元方法与显微组织演化模型相集成建立了基于浮动凹模设计的齿轮成形有限元模型。采用Gleeble热力模拟实验和定量金相分析技术获得镁合金高温流动应力曲线和动态再结晶模型。数值模拟和实验检验表明,由于齿轮形状复杂,且坯料与模具间存在接触摩擦,齿轮各部位变形和显微组织存在不均匀现象。变形温度降低或者变形速率增加,有利于获得平均晶粒尺寸细小的组织,但是变形和显微组织不均匀性增大,其原因和流动应力曲线特征有关。

Tunable liquid crystal grating based holographic 3D display system with wide viewing angle and large size

As one of the most ideal display approaches,holographic 3-dimensional(3D)display has always been a research hotspot since the holographic images reproduced in such system are very similar to what humans see the actual environment.However,current holographic 3D displays suffer from critical bottlenecks of narrow viewing angle and small size.Here,we propose a tunable liquid crystal grating-based holographic 3D display system with wide viewing angle and large size.Our tunable liquid crystal grating,providing an adjustable period and the secondary diffraction of the reconstructed image,enables to simultaneously implement two different hologram generation methods in achieving wide viewing angle and enlarged size,respectively.By using the secondary diffraction mechanism of the tunable liquid crystal grating,the proposed system breaks through the limitations of narrow viewing angle and small size of holographic 3D display.The proposed system shows a viewing angle of 57.4°,which is nearly 7 times of the conventional case with a single spatial light modulator,and the size of the reconstructed image is enlarged by about 4.2.The proposed system will have wide applications in medical diagnosis,advertising,education and entertainment and other fields.

Cryptochrome-mediated hypocotyl phototropism was regulated antagonistically by gibberellic acid and sucrose in Arabidopsis

Both phototropins(phot1 and phot2)and cryptochromes(cry1 and cry2)were proven as the Arabidopsis thaliana blue light receptors.Phototropins predominately function in photomovement,and crypto-chromes play a role in photomorphogenesis.Although cryptochromes have been proposed to serve as positive modulators of phototropic responses,the underlying mechanism remains unknown.Here,we report that depleting sucrose from the medium or adding gibberellic acids(GAs)can partially restore the defects in phototropic curvature of the phot1 phot2 double mutants under high-intensity blue light;this restoration does not occur in phott phot2 cry1 cry2 quadruple mutants and nph3(nonphototropic bypocotyl 3)mu-tants which were impaired phototropic response in sucrose-containing medium.These results indicate that GAS and sucrose antgonistically regulate hypocotyl phototropism in a cryptochromes dependent manner,butit showed a crosstalk with phototropin signaling on NPH3.Furthermore,cryptochromes activation by blue light inhibit GAS synthesis,thus stabilizing DELLAS to block hypocotyl growth,which result in the higher GAs content in the shade side than the lit side of hypocotyl to support the asymmetric growth of hypocotyl.Through modulationof the abundance of DELLAS by sucrose depletion or added GAs,it revealed that cryptochromes have a function in mediating phototropic curvature.

Controlling Flow Instability in Straight Spur Gear Forging Using Numerical Simulation and Response Surface Method

Workability domain without the onset of flow instability was developed by numerical simulation and response surface method(RSM) for complex-shaped straight spur gear forging. The processing map of AZ31 B alloys was calculated from flow stress curves and then integrated with the finite element model to simulate the distribution of flow instability in the straight spur gear undergoing isothermal forging process. Occurrence of flow instability depends on forging temperature, punch velocity and billet reduction. Taking forging temperature and punch velocity as design variables, while billet reduction as response variable, RSM of workability domain was established. Analysis of variance indicates that forging temperature is the most significant factor determining the appearance of flow instability in the forged gear. Flow instability is easier to take place at lower temperatures of 250 and 300 °C in the early stage of forging but at higher temperatures of 350 and 400 °C in the later stage of forging, which is attributed to different deformation mechanisms and dynamic recrystallization behaviors at different temperatures or deformation levels. Meanwhile, increasing punch velocity further reduces the workability of the forged gear.Four different processing paths were chosen to carry out the gear forging trials. Visual observations and metallographic examinations demonstrate that the developed workability domain contributes to optimization of forging parameters.

Deformation Mechanism and Hot Workability of Extruded Magnesium Alloy AZ31

Using the flow stress curves obtained by Gleeble thermo-mechanical testing, the processing map of extruded magnesium alloy AZ31 was established to analyze the hot workability. Stress exponent and activation energy were calculated to characterize the deformation mechanism. Then, the effects of hot deformation parameters on deformation mechanism,microstructure evolution and hot workability of AZ31 alloy were discussed. With increasing deformation temperature, the operation of non-basal slip systems and full development of dynamic recrystallization(DRX) contribute to effective improvement in hot workability of AZ31 alloy. The influences of strain rate and strain are complex. When temperature exceeds 350 °C, the deformation mechanism is slightly dependent of the strain rate or strain. The dominant mechanism is dislocation cross-slip, which favors DRX nucleation and grain growth and thus leads to good plasticity. At low temperature(below 350 °C), the deformation mechanism is sensitive to strain and strain rate. Both the dominant deformation mechanism and inadequate development of DRX deteriorate the ductility of AZ31 alloy. The flow instability mainly occurs in the vicinity of 250 °C and 1 s-1.