Genome-wide identification of the CONSTANS-LIKE(COL)family and mechanism of fruit senescence regulation by PpCOL8 in sand pear(Pyrus pyrifolia)

Pyrus pyrifolia Nakai‘Whangkeumbae'is a sand pear fruit with excellent nutritional quality and taste.However,the industrial development of pear fruit is significantly limited by its short shelf life.Salicylic acid(SA),a well-known phytohormone,can delay fruit senescence and improve shelf life.However,the mechanism by which SA regulates CONSTANS-LIKE genes(COLs)during fruit senescence and the role of COL genes in mediating fruit senescence in sand pear are poorly understood.In this study,22 COL genes were identified in sand pear,including four COLs(Pp COL8,Pp COL9a,Pp COL9b,and Pp COL14)identified via transcriptome analysis and 18 COLs through genome-wide analysis.These COL genes were divided into three subgroups according to the structural domains of the COL protein.Pp COL8,with two B-box motifs and one CCT domain,belonged to the first subgroup.In contrast,the other three Pp COLs,Pp COL9a,Pp COL9b,and Pp COL14,with similar conserved protein domains and gene structures,were assigned to the third subgroup.The four COLs showed different expression patterns in pear tissues and were preferentially expressed at the early stage of fruit development.Moreover,the expression of Pp COL8 was inhibited by exogenous SA treatment,while SA up-regulated the expression of Pp COL9a and Pp COL9b.Interestingly,Pp COL8 interacts with Pp MADS,a MADS-box protein preferentially expressed in fruit,and SA up-regulated its expression.While the production of ethylene and the content of malondialdehyde(MDA)were increased in Pp COL8-overexpression sand pear fruit,the antioxidant enzyme(POD and SOD)activity and the expression of Pp POD1 and Pp SOD1 in the sand pear fruits were down-regulated,which showed that Pp COL8 promoted sand pear fruit senescence.In contrast,the corresponding changes were the opposite in Pp MADS-overexpression sand pear fruits,suggesting that Pp MADS delayed sand pear fruit senescence.The co-transformation of Pp COL8 and Pp MADS also delayed sand pear fruit senescence.The results of this study revealed that Pp COL8 can play a key role in pear fruit senescence by interacting with Pp MADS through the SA signaling pathway.

A novel Ag/ZnO core-shell structure for efficient sterilization synergizing antibiotics and subsequently removing residuals

The massive use of antibiotics has led to the aggravation of bacterial resistance and also brought environmental pollution problems.This poses a great threat to human health.If the dosage of antibiotics is reduced by increasing its bactericidal performance,the emergence of drug resistance is certainly delayed,so that there's not enough time for developing drug resistance during treatment.Therefore,we selected typical representative materials of metal Ag and semiconductor ZnO nano-bactericides to design and synthesize Ag/ZnO hollow core-shell structures(AZ for short).Antibiotics are grafted on the surface of AZ through rational modification to form a composite sterilization system.The research results show that the antibacterial efficiency of the composite system is significantly increased,from the sum(34.7%+22.8%-57.5%)of the antibacterial efficiency of AZ and gentamicin to 80.2%,net synergizes 22.7%,which fully reflects the effect of 1+1>2.Therefore,the dosage of antibiotics can be drastically reduced in this way,which makes both the possibility of bacterial resistance and medical expenses remarkably decrease.Subsequently,residual antibiotics can be degraded under simple illumination using AZ-self as a photocatalyst,which cuts off the path of environmental pollution.In short,such an innovative route has guiding significance for drug resistance.

面向数字时代重置教育和培训——欧盟《数字教育行动计划(2021-2027)》的要点和启示

为解决欧盟成员国之间数字教育不均衡、教师数字素养不足、新冠肺炎疫情期间在线教育大规模紧急使用引发的诸多问题等,欧盟委员会发布《数字教育行动计划(2021—2027)》,提出两大战略重点和14项行动举措。这是欧盟继2018年颁布首份数字教育行动计划后的第二份计划,其中两个战略重点分别是促进高性能数字教育生态系统的发展、提高人们应对数字化转型的数字技能和能力,旨在提高欧盟公民的数字素养,发展更高质量、更易获得和更具包容性的数字化教学、学习和评估。我国十分重视教育数字化转型工作,正在实施教育数字化战略行动,但目前还缺乏关于数字教育发展战略规划和行动计划,建议尽快制定中国数字教育战略行动计划,积极构建数字教育生态系统,加强数字教育国际交流与合作,不断提高全民应对数字化转型的数字技能和能力。

Divergent evolutionary patterns of the MAPK cascade genes in Brassica rapa and plant phylogenetics

Mitogen-activated protein kinase(MAPK)cascade signal transduction modules play crucial roles in regulating many biological processes in plants.These cascades are composed of three classes of hierarchically organized protein kinases,MAPKKKs,MAPKKs and MAPKs.Here,we analyzed gene retention,phylogenetic,evolution and expression patterns of MAPK cascade genes in Brassica rapa.We further found that the MAPK branches,classes III and IV,appeared after the split of bryophytes and green algae after analyzing the MAPK cascade genes in 8 species,and their rapid expansion led to the great size of the families of MAPKs.In contrast,the ancestral class I subfamily of MAPKK gene families have been highly conserved from algae to angiosperms.For the MAPKKK family,the MEKK and Raf subfamily share a common evolutionary origin,and Raf plays a major role in the expansion of the MAPKKK gene family.The cis-elements and interaction network analyses showed the important function of MAPK cascade genes in development and stress responses in B.rapa.This study provides a solid foundation for molecular evolution analyses of MAPK cascade genes.

Flexible Task Scheduling Based on Edge Computing and Cloud Collaboration

With the rapid development and popularization of 5G and the Internetof Things, a number of new applications have emerged, such as driverless cars.Most of these applications are time-delay sensitive, and some deficiencies werefound during data processing through the cloud centric architecture. The data generated by terminals at the edge of the network is an urgent problem to be solved atpresent. In 5 g environments, edge computing can better meet the needs of lowdelay and wide connection applications, and support the fast request of terminalusers. However, edge computing only has the edge layer computing advantage,and it is difficult to achieve global resource scheduling and configuration, whichmay lead to the problems of low resource utilization rate, long task processingdelay and unbalanced system load, so as to lead to affect the service quality ofusers. To solve this problem, this paper studies task scheduling and resource collaboration based on a Cloud-Edge-Terminal collaborative architecture, proposes agenetic simulated annealing fusion algorithm, called GSA-EDGE, to achieve taskscheduling and resource allocation, and designs a series of experiments to verifythe effectiveness of the GSA-EDGE algorithm. The experimental results showthat the proposed method can reduce the time delay of task processing comparedwith the local task processing method and the task average allocation method.

Study on stability of permafrost slopes during thawing

A numerical simulation platform that analyzes the variation of the slope factor of safety with time instantaneously is proposed based on heat conduction theory to study the law of stability development of permafrost slopes during thawing.This platform considers ice-water phase change,elastoplastic constitutive behavior and strength reduction in thawing permafrost and can evaluate the factor of safety of permafrost slopes with different slope angles and water contents.Results indicate that under different slope angles and water contents,the evolution of the factor of safety with time displays two stages:nonlinearly decreasing at first and then essentially remaining constant.During the decreasing stage,the plastic slip line overlaps with the thawing front.In this stage,the selfweight of the post-thawed permafrost layer increases continuously while the shear strength of the frozen-thaw interface keeps unchanged.This is the main reason leading to the decrease in the factor of safety.In the second stage,the thawing depth increases continuously while the position of the plastic slip line remains unchanged,resulting in a constant safety factor stage.

Hypoxia Imaging of Rodent Xenografts with ¹⁸F-Fluoromisonidazole: Comparison of Dynamic and Static PET Imaging

Purpose: To generate parametric images of tumor hypoxia in a tumor-bearing rat model using voxel-based compartmental analysis of dynamic fluorine-18 labeled misonidazole (18F-FMISO) microPET? images, and to compare the parametric images thus derived with static “late” 18F-FMISO microPET? images for the detection of tumor hypoxia. Materials and Methods: Nude rats bearing HT-29 colorectal carcinoma xenografts (≈1.5 - 2 cm in diameter) in the right hind limb were positioned in a custom-fabricated, animal-specific foam mold. Animals were injected via the tail vein with ≈55.5 MBq 18F-FMISO and continuously imaged for either 60 or 120 minutes, with additional late static images up to 3 hour post-injection. The raw list-mode data was reconstructed into 37 - 64 frames with earlier frames of shorter time durations (12 - 15 seconds) and later frames of longer durations (up to 300 seconds). Time activity curves (TACs) were generated over regions encompassing the tumor as well as an artery, the latter for use as an input function. A beta version of a compartmental modeling package (BioGuide?, Philips Healthcare) was used to generate parametric images of k3 and Ki, rate constants of entrapment and flux of 18F-FMISO, respectively. Results: Data for 7 HT-29 tumor xenografts were presented, 6 of which yielded clear areas of tumor hypoxia as defined by Ki/k3 maps. Importantly, intratumoral foci with high 18F-FMISO uptakes on the late images did not always exhibit high Ki/k3 values and may there- fore represent false-positives for radiobiologically significant hypoxia. Conclusions: This study attempts to quantify tumor hypoxia using compartmental analysis of dynamic 18F-FMISO PET images in rodent xenograft tumor models. The results demonstrate feasibility of the approach in small-animal imaging studies, and provide evidence for the possible unreliability of late-time static imaging of 18F-FMISO PET in identifying tumor hypoxia.

环境保护税对中国空气质量影响的研究

随着经济的快速发展,我国的环境问题日益严峻,为了降低污染,提高环境质量,落实生态文明建设,2018年1月1日起我国开始征收环境保护税。本文通过对全国2016年-2020年的主要空气污染物月平均浓度的整理和计算,研究分析了环境保护税的征收对中国空气质量的影响,研究结果表明征收环境保护税可以有效降低空气污染,提高环境质量,并据此为完善环境保护税制提出了几点建议。

高分子囊泡领域面临的挑战和未来研究方向

作为细胞中的主要运输系统,天然囊泡在物质的定点输运过程中具有至关重要的作用.高分子囊泡是与之结构相似的一种人工囊泡,具有优异的膜稳定性和胶体稳定性、高药物负载率、低膜穿透性、优异的可修饰性和长循环时间等优势,在生物医用领域具有广泛的应用前景.然而,目前该领域尚面临一系列重要挑战,如合成和制备方法较为复杂、生物相容性较难预测、功能和递送途径有限等,限制了其临床转化之路.本文从囊泡的构建模块合成、自组装技术和潜在的生物医学应用等角度,提出了设计和制备下一代高分子囊泡需要解决的五个关键科学问题,指出了未来面临的重要挑战和发展方向,例如简化设计和合成过程,优化和规范自组装过程,拓展潜在的应用前景.

Remodeling of the ryanodine receptor isoform 1 channel regulates the sweet and umami taste perception of Rattus norvegicus

Sweet and umami tastes are elicited by sweet and umami receptors on the tongue and palate epithelium,respectively.However,the molecular machinery allowing the taste reaction remains incompletely understood.Through a phosphoproteomic approach,we identified the key proteins that trigger taste mechanisms based on phosphorylation cascades.Ryanodine receptor isoform 1(RYR1)was further verified by sensory and behavioral assays.We propose a model of RYR1-mediated sweet/umami signaling in which the RYR1 channel,which mediates Ca^(2+)release from the endoplasmic reticulum,is closed by dephosphorylation in bud tissue after sweet/umami treatment.The alteration in Ca^(2+)content in the cytosol induces transient membrane depolarization and generates a cell current for taste signal transduction.We demonstrate that RYR1 is a new channel involved in the regulation of sweet/umami signal transduction and propose a“metabolic clock”notion based on sweet/umami sensing.Our study provides a valuable foundation for a system-level understanding of the taste perception mechanism.

A STIR nucleic acid drug delivery system for stirring phenotypic switch of microglia in Parkinson’s disease treatments

Neuroinflammation is one of the three important pathological features in neurodegenerative diseases including Parkinson’s disease(PD).The regulation of neuroinflammation can reduce the severity of neurological damage to alleviate diseases.Numerous studies have shown that the phenotype switch of microglia is tightly associated with the nuclear factorκB(NF-κB)-mediated inflammatory pathway.Therefore,the small interfering RNA(siRNA)therapy for downregulating the expression of NF-κB,provides a promising therapeutic strategy for Parkinson’s disease treatments.Considering the brain delivery challenges of siRNA,a sequential targeting inflammation regulation(STIR)delivery system based on poly(amino acid)s is developed to improve the therapeutic effects of Parkinson’s disease treatments.The STIR system sequentially targets the blood–brain barrier and the microglia to enhance the effective concentration of siRNA in the targeted microglia.The results demonstrate that the STIR nanoparticles can transform microglial phenotypes and regulate brain inflammation,thus achieving neuronal recovery and abnormal aggregation ofα-synuclein protein(α-syn)reduction in the treatment of Parkinson’s disease.Herein,this STIR delivery system provides a promising therapeutic platform in PD treatments and has great potential for other neurodegenerative diseases’therapies.

Experimental investigation of characteristics of instability evolution in a centrifugal compressor

The stable range of operation for the centrifugal compressor significantly influences the dynamic,economic,and environment-friendly characteristics of power systems.A deep understand-ing of the characteristics of instability evolution is necessary to improve the compressor stability.A centrifugal compressor equipped with a vaneless diffuser is experimentally investigated using high-response static-pressure measurements.The results obtained indicate that three typical rotational-speed ranges exist based on the different instability evolution characteristics,which reveals the var-ious impeller–diffuser matching behaviors over the entire speed range.At low-speed ranges((40%–75%)N_(max),N_(max)is the maximum rotational speed),the compressor exhibits stable,Rotating Insta-bility(RI),impeller stall(diffuser stall),and surge modes.The impeller stall mode is induced by RI and propagates downstream,resulting in the diffuser stall and compressor surge modes.In the medium-speed range((75%–85%)N_(max)),the compressor exhibits stable,diffuser stall,RI,and surge modes.In the high-speed range((85%–100%)N_(max)),the compressor exhibits stable,diffuser stall,and surge modes.The dominant instability position is shifted from the impeller to the diffuser as the rotational speed increases.Both the impeller and diffuser stall present an irregular sawtooth static-pressure wave and exhibit broadband frequency spectrum patterns.

Parallel all-optical logic operations based on metasurface polarization optics

We developed a general framework for parallel all-optical logic operations with independent phase control of arbitrary orthogonal polarization state enabled by a single-layer metasurface.A pair of orthogonal circular polarized bases are used as two input channels of the logic operator,and their four combinations perfectly match various binary input states.Correspondingly,distinct phase profiles are encoded into the metasurface,which enables parallel operation of the two logic gates by way of polarization switching.It allows for an efficient and compact way to implement multi-channel multiplexed logic gate operations with the capability of fast optical computing at the chip scale.

抗恶意敌手的百万富翁问题解决方案

安全多方计算是国际密码学界研究的热点,百万富翁问题是安全多方计算最基础最重要的问题,是构造其他安全多方计算协议的基本模块.这个问题已经有许多解决方案,但除了基于混淆电路的协议之外,目前基于公钥加密算法的解决方案几乎都是半诚实模型下的解决方案,抗恶意敌手的解决方案极少,仅有的个别解决方案效率很低,这制约着恶意模型下许多安全多方计算问题的解决.抗恶意敌手的解决方案更符合安全多方计算的实际应用场景,研究抗恶意敌手的百万富翁问题解决方案,具有重要的理论与现实意义.本文首先设计了一个半诚实模型下百万富翁问题的解决方案,进一步分析了恶意敌手可能的恶意行为,并用零知识证明和分割选择阻止或发现这些恶意行为,将半诚实模型下安全的计算协议改造成恶意模型下安全的计算协议,并用理想–实际范例证明了协议的安全性,分析了恶意敌手攻击成功的概率和方案的效率.理论分析表明与现有方案相比,我们提出的方案效率至少提高6倍.

Fabrication and long persistent luminescence of Ce3+-Cr3+co-doped yttrium aluminum gallium garnet transparent ceramics

Pe rsistent luminescence(Pers L)materials are widely used in safety indication,traffic and transportation signs,architectural decoration and other fields.In this paper,(Y_(1-x)Ce_(x))(Al_(0.9995)Cr_(0.0005))_(2)Ga_(3)O_(12)(x=0.001,0.002,0.003,0.005)transparent ceramics were successfully prepared by solid-state reaction method in air followed by HIP post-treatment.With the increase of Cedoping concentration,the optical quality of the as-prepared ceramics is improved and the morphology is denser.Luminescent quenching occurs when the Ceconcentration is more than 0.2%.The as-prepared transparent ceramics we re annealed in different atmosphere s.From the PersL decay curve s,the transparent ce ramics after air annealing show the best PersL performance:luminance with 4424.0 mcd/m^(2)and PersL duration over865 min after ceasing 365 nm excitation,respectively.The effects of Cedoping concentration and annealing atmospheres are also discussed in detail.

Concurrent validity of evaluating knee kinematics using Kinect system during rehabilitation exercise

Squats,ascending and descending stairs,and lunges are three functional movements popularly used in clinical rehabilitation.This study aimed to analyze the validity of the Kinect v2 for assessing the kinematics of three functional knee movements.An intelligent program was developed for real-time kinematic evaluation of the knee joint using the Kinect v2 system.Based on image recognition technology,images from the Kinect v2 depth camera were used to develop a kinematic evaluation program for knee joint movements.The kinematics of 30 healthy volunteers during stair ascent and descent,squatting,and lunging movements were collected synchronously with both VICON and Kinect systems.The peak knee angles in the sagittal and coronal planes were extracted and analyzed.A paired samples t-test and the relative coefficient within the groups were used for statistical analysis of the validity of the Kinect compared to the VICON.There was no significant difference(p>0.05)in bilateral knee flexion angle when lunging.No significant difference(p>0.05)was found in left knee flexion during squatting exercises.Although the Kinect generally underestimated knee flexion and valgus,it displayed excellent consistency and good to excellent agreement with the VICON motion analysis system.The results demonstrated that the Kinect based measurement tool for analyzing knee kinematics has the potential to be an effective clinical training device for maintaining knee alignment during exercise.

Effect of cationic groups in organic sulfide electrolyte on the performance of CdS quantum dot sensitized solar cells

Two organic sulfide redox couples derived from2-mercapto-5-methyl-1,3,4-thiadiazole(McMT):tetrabutylammonium thiolate(McMT-TBA?)/disulfide dimer(BMT)and tetramethylammonium thiolate(McMTTMA?)/BMT were incorporated into quantum dots sensitized solar cells(QDSCs)as alternatives to the inorganic polysulfide electrolyte(Na2S/S).It was found in symmetrical cells test that the interfaces of the organic sulfide electrolytes/platinum counter-electrode have much lower charge transfer resistances as well as higher interface reaction rates compared with that for the inorganic one.Besides,QDSCs based on organic sulfide electrolytes exhibited obviouslyhigher fill factors,open circuit photovoltages,and therefore higher conversion efficiency,thanks to the prohibited recombination and lower redox potential.In addition,by comparing and analyzing the performance of devices based on organic sulfide electrolytes with different cationic groups,it is found that cationic group TMA?with smaller size was favorable for the mass transport in the electrolyte,which explains the better photovoltaic performance of McMT-TMA?/BMT based solar cell than that of McMT-TBA?/BMT based one.Eventually,a power conversion efficiency(PCE)of 0.63%was achieved for QDSCs using McMT-(TMA?)/BMT redox couple as electrolyte,which was till now the highest for CdS QDSC based on organic sulfide electrolyte.

主动穿细胞转运的定向纳米载体用于化学-免疫治疗抑制肿瘤生长及转移

目前免疫治疗已经显示出了极大的肿瘤治疗潜力,然而纳米载体较低的转运能力以及肿瘤免疫响应性低等问题严重阻碍了免疫治疗的临床应用.为了解决这些问题,本课题研制了一种具有主动穿细胞转运能力的定向纳米载体用于化疗增强的免疫治疗.当该纳米载药系统到达肿瘤部位,金属基质蛋白酶2响应的纳米外壳崩解,释放出带有正电荷的纳米内核.正电荷促使纳米内核产生吸附介导的胞吞,进而促进纳米载药系统的跨血管内皮细胞运输和跨细胞药物递送,并最终将药物递送到远端肿瘤细胞中. PD-L1抗体和化疗药物分别被载于纳米载体的外壳和内核中进行精准递送,从而达到对具有不同治疗靶点的药物同步递送、定向释药的目的.肿瘤微环境中释放的PD-L1抗体作用于T细胞表面的特异性受体,阻断了T细胞与肿瘤细胞的结合.正电荷纳米内核同步运载奥沙利铂和吲哚美辛进入深层肿瘤细胞,在整个肿瘤组织中引发免疫原性死亡、逆转免疫抑制作用,招募大量的T细胞并最终增强免疫治疗疗效.本研究中所构建的纳米载药体系不仅能够抑制原位瘤生长,还能够阻止肿瘤的转移.这为化疗增强的免疫治疗提供了一种新的纳米递送方案,提高了免疫治疗在免疫响应率低的肿瘤中的疗效.

Dual inhibition of glycolysis and oxidative phosphorylation by aptamer-based artificial enzyme for synergistic cancer therapy

Dual inhibition of glycolysis and oxidative phosphorylation(OXPHOS)can break the metabolic plasticity of cancer cells to inhibit most energy supply and lead to effective cancer therapy.However,the pharmacokinetic difference among drugs hinders these two inhibitions to realize a uniform temporal and spatial distribution.Herein,we report an aptamer-based artificial enzyme for simultaneous dual inhibition of glycolysis and OXPHOS,which is constructed by arginine aptamer modified carbon-dots-doped graphitic carbon nitride(AptCCN).AptCCN can circularly capture intracellular arginine attribute to the specific binding ability of arginine aptamers to arginine,and further catalyze the oxidation of enriched arginine to nitric oxide(NO)under red light irradiation.In vitro and in vivo experiments showed that arginine depletion and NO stress could inhibit glycolysis and OXPHOS,leading to energy blockage and apoptosis of cancer cells.The presented aptamer-based artificial enzyme strategy provides a new path for cell pathway regulation and synergistic cancer therapy.

Concurrent validity of a markerless motion capture system for the assessment of shoulder functional movement

As a markerless motion capture system(MLS),the Microsoft Kinect sensor may be a low-cost and portable option for measuring shoulder joint angles.However,the system's concurrent validity to capture shoulder functional movement is unclear.The purpose of this study was to investigate the concurrent validity of MLS for capturing shoulder kinematics during functional movement by comparing the MLS measures to those of the marker-based motion capture system(MBS).Twenty-five healthy participants were included in this study.Using the Microsoft Kinect sensor as the MLS and Vicon as the MBS,six shoulder functional movements were measured in all three anatomical planes concurrently.The six movements included flexion to max,maximum extension,abduction to 90°,internal rotation at 90°abduction,external rotation at 0°abduction,and maximum horizontal adduction.The shoulder joint kinematics was measured with both systems.The MLS showed a good to excellent correlation(r>0.75)with MBS for abduction to 90°,maximum external rotation at 0°abduction and maximum internal rotation at 90°abduction.The results for maximum extension(r=0.727)and maximum horizontal adduction(r=0.619)showed a moderate to good correlation.For maximum flexion,a poor correlation was observed(r=0.479).The validity of the MLS to measure shoulder kinematics would be acceptable.The system demonstrates potential as a measurement tool of joint motions for a function assessment and rehabilitation purpose.