Spectral purification improves monitoring accuracy of the comprehensive growth evaluation index for film-mulched winter wheat

In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge mulching,ridge–furrow full mulching, and flat cropping full mulching in winter wheat.Based on the fuzzy comprehensive evaluation (FCE) method, four agronomic parameters (leaf area index, above-ground biomass, plant height, and leaf chlorophyll content) were used to calculate the comprehensive growth evaluation index (CGEI) of the winter wheat, and 14 visible and near-infrared spectral indices were calculated using spectral purification technology to process the remote-sensing image data of winter wheat obtained by multispectral UAV.Four machine learning algorithms, partial least squares, support vector machines, random forests, and artificial neural network networks(ANN), were used to build the winter wheat growth monitoring model under film mulching, and accuracy evaluation and mapping of the spatial and temporal distribution of winter wheat growth status were carried out.The results showed that the CGEI of winter wheat under film mulching constructed using the FCE method could objectively and comprehensively evaluate the crop growth status.The accuracy of remote-sensing inversion of the CGEI based on the ANN model was higher than for the individual agronomic parameters, with a coefficient of determination of 0.75,a root mean square error of 8.40, and a mean absolute value error of 6.53.Spectral purification could eliminate the interference of background effects caused by mulching and soil, effectively improving the accuracy of the remotesensing inversion of winter wheat under film mulching, with the best inversion effect achieved on the ridge–furrow full mulching area after spectral purification.The results of this study provide a theoretical reference for the use of UAV remote-sensing to monitor the growth status of winter wheat with film mulching.

A Study of Solar Rotation and Differential Rotation

The Sun has solar rotation;nevertheless, many evidences have suggested that different latitude of the Sun rotates in different speed, which is now known as differential rotation. This work calculates the solar rotation speeds near the equator and 30? in the northern hemisphere using Fixed-Point Arithmetic method. The calculated results show a greater speed at the equator than the speed at 30?, indicating that the speed decreases as the latitude becomes higher. .

差速器行星齿轮结构优化

汽车差速器是当车辆行驶在不平路面或转弯等情况时,可使两侧车轮以不同角速度旋转同时传递扭矩,从而消除左、右车轮在汽车运动学上的不协调,是汽车传动系中的关键零部件之一,其力矩的分配和各构件的强度直接决定着车辆的转向性能、通过性和可靠性。差速器内一般包含行星齿轮、半轴齿轮,行星齿轮与半轴齿轮相比体积较小,在承受相同载荷的情况下,行星齿轮更易损坏。本文通过优化行星齿轮结构,达到提高行星齿轮可靠性的目的。

Targeting the PD-L1 cytoplasmic domain and its regulatory pathways to enhance cancer immunotherapy

As a significant member of the immune checkpoint,programmed cell death 1 ligand 1(PD-L1)plays a critical role in cancer immune escape and has become an important target for cancer immunotherapy.Clinically approved drugs mainly target the extracellular domain of PD-L1.Recently,the small cytoplasmic domain of PD-L1 has been reported to regulate PD-L1 stability and function through multiple pathways.Therefore,the intracellular domain of PD-L1 and its regulatory pathways could be promising targets for cancer therapy,expanding available strategies for combined immunotherapy.Here,we summarize the emerging roles of the PD-L1 cytoplasmic domain and its regulatory pathways.The conserved motifs,homodimerization,and posttranslational modifications ofthe PD-L1 cytoplasmic domain have been reported to regulate the membrane anchoring,degradation,nucleartranslocation,and glycosylation of PD-L1.This summary provides a comprehensive understanding of the functions of the PD-L1 cytoplasmic domain and evaluates the broad prospects for targeted therapy.

Hyaluronic acid-based hydrogels with tobacco mosaic virus containing cell adhesive peptide induce bone repair in normal and osteoporotic rats

Tobacco mosaic virus(TMV)has been studied as a multi-functional agent for bone tissue engineering.An osteo-inductive effect of wild-type TMV has been reported,as it can significantly enhance the bone differentiation potential of bone marrow stromal cells both on a two-dimensional substrate and in a three-dimensional(3D)hydrogel system.A TMV mutant(TMV-RGD1)was created which featured the adhesion peptide arginyl-glycyl-aspartic acid(RGD),the most common peptide motif responsible for cell adhesion to the extracellular matrix,on the surface of the virus particle to enhance the bio-functionality of the scaffold material.We hypothesised that the incorporation of either wild-type TMV or TMV-RGD1 in the 3D hydrogel scaffold would induce bone healing in critical size defects of the cranial segmental bone.We have previously tested the virus-functionalised scaffolds,in vitro,with a hyaluronic acid-based system as an in-situ hydrogel platform for 3D cell encapsulation,culture,and differentiation.The results of these experiments suggested the potential of the virus-functionalised hydrogel to promote in vitro stem cell differentiation.The hydrogel-forming system we employed was shown to be safe and biocompatible in vivo.Here,we further explored the physiological responses regarding bone regeneration of a calvarial defect in both normal and osteoporotic ovariectomized rat models.Our results,based on histological analysis in both animal models,suggested that both wild-type TMV and TMV-RGD1 functionalised hydrogels could accelerate bone regeneration,without systemic toxicity,evaluated by blood counts.New bone formation was intensified by the incorporation of the RGD-mutant viral particles.This finding increased the potential for use of the rodshaped plant virus as a platform for the addition of powerful biofunctionality for tissue engineering applications.This study was approved by the Ethics Committee on Animal Use of the Zhenjiang Affiliated First People’s Hospital affiliated to Jiangsu University.