Structural and Functional Insights into an Arabidopsis NBS-LRR Receptor in Nicotiana benthamiana

Nucleotide-binding site leucine-rich repeat receptors (NBS-LRR/NLRs) are crucial intracellular immune proteins in plants. Previous article reported a novel NLR protein SUT1 (SUPPRESSORS OF TOPP4-1, 1), which is involved in autoimmunity initiated by type one protein phosphatase 4 mutation (topp4-1) in Arabidopsis, however, its role in planta is still unclear. This study employed Nicotiana benthamiana, a model platform, to conduct an overall structural and functional analysis of SUT1 protein. The transient expression results revealed that SUT1 is a typical CNL (CC-NBS-LRR) receptor, both fluorescence data and biochemical results showed the protein is mainly anchored on the plasma membrane due to its N-terminal acylation site. Further truncation experiments announced that its CC (coiled-coil) domain possessed cell-death-inducing activity. The outcomes of point mutations analysis revealed that not only the CC domain, but also the full-length SUT1 protein, whose function and subcellular localization are influenced by highly conserved hydrophobic residues. These research outcomes provided favorable clues for elucidating the activation mechanism of SUT1.

The Application of Nicotiana benthamiana as a Transient Expression Host to Clone the Coding Sequences of Plant Genes

Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using complementary DNA (cDNA) derived from messenger RNA (mRNA) extracted from plant tissues and generated by reverse transcription. However, some CDS are difficult to acquire through this process as they are expressed at extremely low levels or have specific spatial and/or temporal expression patterns in vivo. These challenges require the development of alternative CDS cloning technologies. In this study, we found that the genomic intron-containing gene coding sequences (gDNA) from Arabidopsis thaliana, Oryza sativa, Brassica napus, and Glycine max can be correctly transcribed and spliced into mRNA in Nicotiana benthamiana. In contrast, gDNAs from Triticum aestivum and Sorghum bicolor did not function correctly. In transient expression experiments, the target DNA sequence is driven by a constitutive promoter. Theoretically, a sufficient amount of mRNA can be extracted from the N. benthamiana leaves, making it conducive to the cloning of CDS target genes. Our data demonstrate that N. benthamiana can be used as an effective host for the cloning CDS of plant genes.

铜乙二胺法测定中国手工纸纤维素特性粘度的改进实验

介绍了一个通过铜乙二胺法测定纤维素特性粘度的改进实验。在该方法中,木质素对纤维素特性粘度的测定会产生巨大影响。为了探讨这一问题,本实验构建纤维素-木质素模型,讨论了木质素含量对纤维素特性粘度的影响,并采用改进的计算方法获得了更加准确的纤维素特性粘度和聚合度。此外,还探讨了与空气接触时,不同溶解时间对纤维素铜乙二胺特性粘度的影响。该实验是纤维素相关材料的基本表征实验,学生可以了解纤维素的基本性质和溶解机理,以及高分子材料粘度的测定和粘度计的使用方法,还可以学习构建简单模型对各组分影响进行探讨。

Network Security Situation Awareness Framework based on Threat Intelligence

Network security situation awareness is an important foundation for network security management,which presents the target system security status by analyzing existing or potential cyber threats in the target system.In network offense and defense,the network security state of the target system will be affected by both offensive and defensive strategies.According to this feature,this paper proposes a network security situation awareness method using stochastic game in cloud computing environment,uses the utility of both sides of the game to quantify the network security situation value.This method analyzes the nodes based on the network security state of the target virtual machine and uses the virtual machine introspection mechanism to obtain the impact of network attacks on the target virtual machine,then dynamically evaluates the network security situation of the cloud environment based on the game process of both attack and defense.In attack prediction,cyber threat intelligence is used as an important basis for potential threat analysis.Cyber threat intelligence that is applicable to the current security state is screened through the system hierarchy fuzzy optimization method,and the potential threat of the target system is analyzed using the cyber threat intelligence obtained through screening.If there is no applicable cyber threat intelligence,using the Nash equilibrium to make predictions for the attack behavior.The experimental results show that the network security situation awareness method proposed in this paper can accurately reflect the changes in the network security situation and make predictions on the attack behavior.

First-principles investigation of the significant anisotropy and ultrahigh thermoelectric efficiency of a novel two-dimensional Ga_(2)I_(2)S_(2) at room temperature

Two-dimensional(2D)thermoelectric(TE)materials have been widely developed;however,some 2D materials exhibit isotropic phonon,electron transport properties,and poor TE performance,which limit their application scope.Thus,exploring excellent anisotropic and ultrahigh-performance TE materials are very warranted.Herein,we first investigate the phonon thermal and TE properties of a novel 2D-connectivity ternary compound named Ga2I2S2.This paper comprehensively studies the phonon dispersion,phonon anharmonicity,lattice thermal conductivity,electronic structure,carrier mobility,Seebeck coefficient,electrical conductivity,and the dimensionless figure of merit(ZT)versus carrier concentration for 2D Ga_(2)I_(2)S_(2).We conclude that the in-plane lattice thermal conductivities of Ga_(2)I_(2)S_(2) at room temperature(300 K)are found to be 1.55 W mK^(−1) in the X-axis direction(xx-direction)and 3.82 W mK^(−1)in the Y-axis direction(yy-direction),which means its anisotropy ratio reaches 1.46.Simultaneously,the TE performance of p-type and n-type doping 2D Ga2I2S2 also shows significant anisotropy,giving rise to the ZT peak values of p-type doping in xx-and yy-directions being 0.81 and 1.99,respectively,and those of n-type doping reach ultrahigh values of 7.12 and 2.89 at 300 K,which are obviously higher than the reported values for p-type and n-type doping ternary compound Sn2BiX(ZT∼1.70 and∼2.45 at 300 K)(2020 Nano Energy 67104283).This work demonstrates that 2D Ga_(2)I_(2)S_(2) has high anisotropic TE conversion efficiency and can also be used as a new potential room-temperature TE material.

前哨淋巴结活检术在结直肠癌中的应用研究(英文)

Objective:The aim of this study was to investigate the feasibility of sentinel lymph node biopsy(SLNB) in colorectal cancer.Methods:Twenty patients of colorectal cancer were enrolled in this study.Endoscopic injection submucosally of 99mTc-DX was performed around the primary tumor 3 h before operation.Immediately after laparotomy, methylene blue was injected into subserosal layer adjacent to the tumor.Sentinel lymph nodes(SLNs) were defined as blue stained nodes or(and) those containing 10 times more radioactivity than surrounding tissue with a γ probe, all resected nodes were examined postoperatively by routine rapid frozen examination and HE stain.The diagnostic nodes metastasis states and false-negative rate of regional lymph node status on the basis of SLNs were calculated respectively.Results:SLNs were detected in 16 of 20 patients with a successful detection rate of 80%, the number of SLNs ranged from 1 to 3, with a mean value of 2.4 per case, metastasis rate of SLNs were 37.5%(18/48), the diagnostic sensitivity was 80%(16/20), the diagnostic accuracy was 83.3%(15/18), the false-negative rate was 20%(4/20).Conclusion:The SLN concept is validated in colorectal cancer.Combined-agent SLN mapping is an accurate diagnostic procedure for detecting lymph node metastasis in patients with colorectal cancer and may indicate rational extent of lymphadenectomy for colorectal cancer.

Total Synthesis of Dimeric HPI Alkaloids

In this paper,we report a full account of the synthesis of dimeric hexahydropyrroloindole alkaloids and its analogues.The key feature of our new strategy is the novel catalytic copper(10%)mediated intramolecular arylations of o-haloanilides followed by intermolecular oxidative dimerization of the resulting oxindoles in one pot.This sequential reaction leads to the key intermediates for the synthesis of(+)-chimonanthine,(+)-folicanthine,(-)-calycanthine and(-)-ditryptophenaline.Graphical Abstract In the presence of catalytic amount of cuprous iodide(10%),an intramolecular arylation of ohaloanilides followed by an intermolecular oxidative dimerization of the resulting oxindoles leads to a commonintermediate for the synthesis of(+)-chimonanthine,(+)-folicanthine and(-)-calycanthine.Based on this cascade sequence,we also developed a flexible strategy towards the asymmetric syntheses of dimeric HPI alkaloids(-)-ditryptophenaline and its analogues.

Screening and Identifying of Interaction Protein AtL5 in Arabidopsis thaliana

Research background: The Arabidopsis-resistance protein L5 (AT1G12290) can trigger cell death in Nicotiana benthamiana, which is a characteristic function of an NBS-LRR (Nucleotide-Binding Sites and Leucine-Rich Repeat) protein activation. Purpose: To explore the function and molecular regulatory network of L5. Method: We employed yeast two-hybrid technology to search for interacting proteins of L5, combined with laser confocal microscopy to observe the subcellular localization of these candidate proteins, and analyzed the impact of these proteins on L5 function using an Agrobacterium mediated transient expression system. Results: Seven candidate interacting proteins were identified from the Arabidopsis cDNA library, including PPA1 (AT1G01050), RIN4 (AT3G25070), LSU1 (AT3G49580), BZIP24 (AT3G51960), BOI (AT4G19700), RING/U (AT4G22250) and PPA3 (AT2G46860). Functional analysis of these candidate interacting proteins showed that they participated in multiple pathways, including biological and abiotic stress, programmed cell death, protein degradation, material metabolism and transcriptional regulation. The results of laser confocal microscopy manifested that RIN4 was only localized on the plasma membrane (PM), and RING/U was mainly associated with the PM. PPA1, PPA3, LSU1, BZIP24, and BOI all emerged nuclear and cytoplasmic localization. The results of the transient assay proclaimed that both BOI and RING/U can inhibit cell death caused by L5. Conclusions: These results indicate that L5 immune receptors may participate in various pathways, and their protein levels and activities are strictly regulated at multiple levels, providing a basis for elucidating the mechanism of L5 immune receptors in Arabidopsis resistance.

Dissecting Multiple Arabidopsis CC-NBS-LRR Proteins Structure and Localization

NBS-LRR (nucleotide binding sites and leucine rich repeat) protein plays a crucial role as sentries and as defense activators in plants. The structure and function of NBS-LRR proteins are closely related. Previous articles have announced that the activated ZAR1 (HopZ-Activated Resistance 1) forms a pentamer in the plasma membrane, which is a calcium permeable channel that can trigger plant immune signaling and cell death. However, the structure of galore NBS-LRRs in Arabidopsis is not yet clear. The functional sites of distinct NBS-LRR in cells may vary. In addition, identifying pathogens and activating defense regions may occur in different subcellular compartments. Therefore, dissecting the specific structure and positioning of NBS-LRRs is an indispensable step in understanding their functions. In this article, we exploit AlphaFold to predict the structure of some designed NBS-LRRs, and utilize Agroinfiltration transient expression system, combined with biochemical fractionation, to dissect the localization of these NBS-LRR receptors from Arabidopsis. Structural data indicates that the identified NBS-LRRs share analogous conformation. Membrane fractionation assay demonstrates these NBS-LRRs are mainly associated with the membrane. These data show that the Ca2+-permeable channel activity may be evolutionarily conserved in NBS-LRR of Arabidopsis, and this study provides some reference clues for analyzing the structure and localization patterns of other plant immune receptors.

An optical analogue for rotating BTZ black holes

We demonstrate an optical realization for the rotating BTZ black hole using the recent popular photon fluid model in an optical vortex but with a new proposed expression for the optical phase.We also give the numerical realization for the optical vortex to ensure that it can be generated experimentally.Different from the earlier suggestions for the analogue rotating black holes,our proposal includes an inner horizon in the analogue black hole structure.Such structure can keep for a long distance for the convenience of observing analogue Hawking or Penrose radiations.

Thermal Deformation Behavior and Processing Map of a Novel CrFeNiSi_(0.15)Medium Entropy Alloy

The thermal deformation behavior of a novel CrFeNiSi_(0.15)medium entropy alloy(MEA)was studied via isothermal compression experiments,with the processing parameter range of 900–1200℃and 0.001–1 s^(−1).According to experimental data,the modified constitutive equation had been obtained,which precisely predicted the flow behavior of CrFeNiSi_(0.15)MEA during thermal deformation.At the same time,the processing map was established on the basis of the dynamic material model(DMM)theory.According to the map,the optimal processing parameters were determined at 1130–1200℃/0.06–1 s−1,under which the power dissipation efficiency could reach above 34%.The peak efficiency was above 38%,which occurred at 1200℃/1 s^(−1).In such parameter,complete dynamic recrystallization(DRX)also occurred.The flow instability of CrFeNiSi_(0.15)MEA was estimated to occur at 900–985℃/0.12–1 s^(−1),which was shown as grain boundaries cracking.Furthermore,both the continuous DRX(CDRX)and discontinuous DRX(DDRX)occurred simultaneously during thermal deformation.Meanwhile,some twins were also newly formed during DRX process,most of which were primary twins.The occurrence of twinning was beneficial to promote the development of DRX behavior.

Million-scale data integrated deep neural network for phonon properties of heuslers spanning the periodic table

Existing machine learning potentials for predicting phonon properties of crystals are typically limited on a material-to-materialbasis, primarily due to the exponential scaling of model complexity with the number of atomic species. We address this bottleneckwith the developed Elemental Spatial Density Neural Network Force Field, namely Elemental-SDNNFF. The effectiveness andprecision of our Elemental-SDNNFF approach are demonstrated on 11,866 full, half, and quaternary Heusler structures spanning 55elements in the periodic table by prediction of complete phonon properties. Self-improvement schemes including active learningand data augmentation techniques provide an abundant 9.4 million atomic data for training. Deep insight into predicted ultralowlattice thermal conductivity (<1 Wm^(−1) K^(−1)) of 774 Heusler structures is gained by p–d orbital hybridization analysis. Additionally, aclass of two-band charge-2 Weyl points, referred to as “double Weyl points”, are found in 68% and 87% of 1662 half and 1550quaternary Heuslers, respectively.

Autonomous atomic Hamiltonian construction and active sampling of X-ray absorption spectroscopy by adversarial Bayesian optimization

X-ray absorption spectroscopy(XAS)is a well-established method for in-depth characterization of electronic structure.In practice hundreds of energy-points should be sampled during the measurements,and most of them are redundant.Additionally,it is also tedious to estimate reasonable parameters in the atomic Hamiltonians for mechanistic understanding.We implement an Adversarial Bayesian optimization(ABO)algorithm comprising two coupled BOs to automatically fit the many-body model Hamiltonians and to sample effectively based on active learning(AL).Taking NiO as an example,we find that less than 30 sampling points are sufficient to recover the complete XAS with the corresponding crystal field and charge transfer models,which can be selected based on intuitive hypothesis learning.Further applications on the experimental XAS spectra reveal that less than 80 sampling points give reasonable XAS and reliable atomic model parameters.Our ABO algorithm has a great potential for future applications on automated physics-driven XAS analysis and AL sampling.

Correspondence(reply):The application conditions of false discovery rate control

We have carefully read the correspondence“False Discov-ery Rate Control in Cancer Biomarker Selection”authored by Li.The author clarified the need of paying attention to the control of false discovery rate(FDR)when screening for cancer biomarkers.They expressed concerns about whether the 30 genes concluded in Figure 7 in our published paper“LPCAT1 functions as a novel prognostic molecular marker in hepatocellular carcinoma”call for FDR control.

Identification of positive cofactor 4 as a diagnostic and prognostic biomarker associated with immune infiltration in hepatocellular carcinoma

Background and aims:Human positive cofactor 4(PC4)is associated with the development and therapeutic resistance of several malignancies.However,the role of PC4 in hepatocellular carcinoma(HCC)remains obscure.Methods:The expression status of PC4 was explored in Gene Expression Omnibus and The Cancer Genome Atlas datasets.Subsequently,the prognostic and diagnostic significance of PC4 in HCC patients was analyzed.Functional enrichment analyses were conducted to explore biological functions and potential mechanisms.The CIBERSORT algorithm was used for immune infiltration analysis.The risk signature was constructed by LASSO-Cox regression and was validated with the International Cancer Genome Consortium dataset.Quantitative real-time polymerase chain reaction was used to verify the expression levels of all genes.Tumor Immune Dysfunction and Exclusion analysis evaluated immunotherapy response.Finally,using online databases,PC4-related competing endogenous RNA networks were constructed.Results:PC4 levels were significantly upregulated in HCC and positively correlated with the pathological grade and clinical stage.The PC4-high expression group showed worse prognosis.In addition,PC4 could distinguish between tumor and normal tissues with an area under the curve of 0.965.The PC4 level was associated with immune checkpoints and immune cell infiltration.In the training and validation sets,the eight-gene risk signature strongly correlated with HCC patient prognosis.Tumor Immune Dysfunction and Exclusion analysis showed that patients in both the PC4-low and low-risk groups were more likely to benefit from immunotherapy.Finally,an lncRNA/microRNA-101-3p/PC4 network was constructed.Conclusion:We confirmed PC4 as a diagnostic and prognostic biomarker in HCC patients.We also developed and validated an eight-gene risk signature,which will help in clinical decision-making.The competing endogenous RNA network could help explore the regulatory mechanisms of PC4 in HCC.

In Silico Screening of Potential Inhibitors against dPLA2 from Named Chinese Herbs for Identification of Compounds with Antivenom Effects Due to Deinagkistrodon acutus Snake Bites

Phospholipase A2 (PLA2) is the key enzyme to the venom from Deinagkistrodon acutus which is one of the highly venomous snakes in China. In addition to being a catalyst for the hydrolysis of phospholipases A2 from snake venom, its well known that it possesses a broad spectrum of pharmacological activities, such as myotoxicity, neurotoxicity, cardiotoxicity, and hemolytic, anticoagulant and antiplatelet activities. However, snakebites are not efficiently treated by conventional serum therapy. Acute wounds can still cause poisoning and death. In order to find effective inhibitors of Deinagkistrodon venom acid phospholipase A2 (dPLA2), we obtained 385 compounds in 9 Chinese herbs from the TCMSP. These compounds were further performed to virtual screen using in silico tools like ADMET analysis, molecular docking and molecular dynamics (MD) simulation. After Pharmacokinetics analysis, we found 7 candidate compounds. Besides, analysis of small molecule interactions with dPLA2 confirmed that the amino acid residues HIS47 and GLY29 are key targets. Because they bind not only to the natural substrate phosphatidylcholine and compounds known for having inhibitory functions, but also for combining with potential antidote molecules in Chinese herbal medicine. This study is the first to report experience with virtual screening for possible inhibitor of dPLA2, such as the interaction spatial structure, binding energy and binding interaction analysis, these experiences not only provide reference for further experimental research, but also have a guideline for the study of drug molecular mechanism of action.

农田节肢动物不同取样方法的综合比较

农田节肢动物多样性具有病虫害控制、传粉等价值,选择一种或多种适宜、准确且高效的取样方法和指示类群来衡量农田节肢动物多样性是一项基础性工作。本文通过地表陷阱法、挂盆陷阱法、扫网法、目测计数法和吸虫器法在有机管理和常规管理农田区的不同农业生境类型中取样,比较不同方法对不同生物类群的捕获效率、经济成本、响应敏感性等。研究发现在捕获效率方面,地陷法和挂盆法最高,其次是扫网法,而吸虫器法和目测计数法较差。挂盆法对步甲、蜘蛛、蜂类和瓢虫类群的捕获效率较佳。陷阱法主要适用于蜘蛛和步甲的取样,扫网法也可用于蜘蛛和瓢虫的取样。在经济成本方面,地陷法的成本最低,扫网法的总成本最高。每种取样方法下仅有个别类群个体数量具有较好的响应敏感性,如地陷法的蜘蛛目个体数和步甲科个体数、挂盆法的总个体数、蜂类个体数和瓢虫科个体数、扫网法的直翅目个体数和半翅目个体数等。在此基础上,综合类群经济价值,操作难易,类群鉴定难度,被动取样程度,是否受取样人影响等比较发现:地陷法对步甲和蜘蛛的取样的综合效果最佳,而不同取样方法下多种类群的组合能更好地监测和评价农田节肢动物多样性的整体情况。地陷法捕获步甲或/和蜘蛛以及挂盆法调查蜂类的组合是基于本研究得出的调查农田节肢动物多样性的最佳组合。

Seed-induced synthesis of functional MFI zeolite materials:Method development,crystallization mechanisms,and catalytic properties

As an important zeolite material,MFI zeolites,as well as their controllable synthesis,are of great interest in both basic and applied science.Among the developed synthetic approaches,the seed-induced method has gradually evolved into a facile,low-cost,and even green alternative to give zeolites the desirable physicochemical properties.In this review,we briefly summarize the development of seed-induced syntheses of diverse functional MFI zeolites,where the“living”seed crystals not only direct the formation of zeolitic framework but also function as special“templates”or“units”to fine-tune the zeolite materials with diverse sizes,shapes,compositions,morphologies and pore structures.Moreover,on the basis of their structural features and crystallization behaviors in seed-induced synthesis,we reveal the roles of seeds and discuss the related crystallization mechanisms including both classical and non-classical pathways.We also want to guide readers to investigate the structure-performance relationships between these functional MFI zeolite catalysts and suitable catalytic reactions.

Constrained crystals deep convolutional generative adversarial network for the inverse design of crystal structures

Autonomous materials discovery with desired properties is one of the ultimate goals for materials science,and the current studies have been focusing mostly on high-throughput screening based on density functional theory calculations and forward modeling of physical properties using machine learning.Applying the deep learning techniques,we have developed a generative model,which can predict distinct stable crystal structures by optimizing the formation energy in the latent space.It is demonstrated that the optimization of physical properties can be integrated into the generative model as on-top screening or backward propagator,both with their own advantages.Applying the generative models on the binary Bi-Se system reveals that distinct crystal structures can be obtained covering the whole composition range,and the phases on the convex hull can be reproduced after the generated structures are fully relaxed to the equilibrium.The method can be extended to multicomponent systems for multi-objective optimization,which paves the way to achieve the inverse design of materials with optimal properties.

超声对晚发型胎儿生长受限不良围产期结局的预测价值

目的探讨超声对晚发型胎儿生长受限(FGR)不良围产期结局的预测因素,并分析其诊断效能。方法回顾性分析2015年12月至2021年5月郑州大学第三附属医院收治的149例产前诊断为晚发型FGR患者的超声声像图及临床资料,按照是否出现不良围产期结局分为不良围产期结局组(72例)和对照组(77例)。记录一般临床资料及分娩前1周内经超声测量的大脑中动脉搏动指数(MCA-PI)、脐动脉搏动指数(UA-PI)、脑胎盘比(CPR)、羊水-脐脑比(AUCR)及估计胎儿体质量(EFW)。采用两独立样本t检验、Mann-WhitneyU检验、χ^(2)检验比较组间上述指标的差异,采用单因素和多因素Logistic逐步回归分析确定晚发型FGR不良围产期结局的预测因素,构建受试者操作特征(ROC)曲线分析各超声参数对不良围产期结局的预测效能。结果与对照组相比,不良围产期结局组AUCR、EFW百分位数、CPR、MCA-PI、最大羊水暗区垂直深度均明显降低[30.63±10.33vs39.70±11.15;3.2(2.1,6.4)vs5.7(3.5,8.9);1.18±0.28vs1.37±0.21;1.22±0.26vs1.34±0.23;27.50(22.00,31.00)mmvs29.00(23.50,34.50)mm],UA-PI明显增高(1.05±0.20vs0.98±0.16),差异具有统计学意义(t=5.138,P<0.001;Z=-4.618,P<0.001;t=4.464,P<0.001;t=3.129,P=0.002;Z=-2.292,P=0.022;t=-2.504,P=0.013)。多因素Logistic逐步回归分析显示AUCR、EFW百分位数、CPR为晚发型FGR不良围产期结局的独立预测因素(OR=0.951、0.753、0.154,P=0.024、<0.001、=0.044)。经过ROC曲线分析,AUCR、EFW百分位数、CPR预测晚发型FGR不良围产期结局的界值、敏感度、特异度分别为39.64、53.2%、81.9%;4.85、66.2%、66.7%;1.19、81.8%、51.4%。AUCR、EFW百分位数、CPR 3个变量联合的多参数模型对不良围产期结局的诊断效能提升,弥补了单项参数预测晚发型FGR不良围产期结局敏感度与特异度失衡的问题,ROC曲线下面积为0.795,敏感度、特异度分别为76.6%、70.8%。结论超声检查在预测晚发型FGR不良围产期结局中具有重要价值,AUCR、EFW百分位数及CPR是晚发型FGR不良围产期结局的独立预测因素,可为产前咨询和临床处理提供依据。