All-Climate Stretchable Dendrite-Free Zn-Ion Hybrid Supercapacitors Enabled by Hydrogel Electrolyte Engineering

Hybrid supercapacitors have shown great potentials to fulfill the demand of future diverse applications such as electric vehicles and portable/wearable electronics.In particular,aqueous zinc-ion hybrid supercapacitors(ZHSCs)have gained much attention due to their low-cost,high energy density,and environmental friendliness.Nevertheless,typical ZHSCs use Zn metal anode and normal liquid electrolyte,causing the dendrite issue,restricted working temperature,and inferior device flexibility.Herein,a novel flexible Zn-ion hybrid supercapacitor(FZHSC)is developed by using activated carbon(AC)anode,δ-MnO_(2) cathode,and innovative PVA-based gel electrolyte.In this design,heavy Zn anode and its dendrite issue are avoided and layered cathode with large interlayer spacing is employed.In addition,flexible electrodes are prepared and integrated with an anti-freezing,stretchable,and compressible hydrogel electrolyte,which is attained by simultaneously using glycerol additive and freezing/thawing technique to regulate the hydrogen bond and microstructure.The resulting FZHSC exhibits good rate capability,high energy density(47.86 Wh kg^(−1);3.94 mWh cm^(−3)),high power density(5.81 kW kg^(−1);480 mW cm^(−3)),and excellent cycling stability(~91%capacity retention after 30000 cycles).Furthermore,our FZHSC demonstrates outstanding flexibility with capacitance almost unchanged even after various continuous shape deformations.The hydrogel electrolyte still maintains high ionic conductivity at ultralow temperatures(≤−30℃),enabling the FZHSC cycled well,and powering electronic timer robustly within an all-climate temperature range of−30~80℃.This work highlights that the promising Zn metal-free aqueous ZHSCs can be designed with great multifunctionality for more practical application scenarios.

Confining MoS_(2) nanocrystals in MOF-derived carbon for high performance lithium and potassium storage

Developing an efficient synthesis protocol to simultaneously control 2D nanomaterials’size and dispersion is the pivot to optimize their electrochemical performance.Herein,we report the synthesis of uniform MoS_(2) nanocrystals well-anchored into the void space of porous carbon(donated as MoS_(2)3C hybrids)by a simple confined reaction in metal–organic framework(MOF)during carbonization process.The strong confinement effect refrain MoS2 growth and aggregation,generating abundant active centers and edges,which contribute fast lithium/potassium reaction kinetics.In addition to the hybridization with the derived carbon,the MoS_(2)3C hybrids exhibit rapid Liþtransfer rate(~109 cm^(2) s 1)and greatly improved electronic conductivity.Consequently,the MoS23C hybrids show ultrafast rate performances and satisfactory cycling stabilities as anode materials for both lithium and potassium ion batteries.This work demonstrates a universal tactic to achieve high dispersive 2D nanomaterials with tailorable particle size.

Reconstruction of vector static magnetic field by different axial NV centers using continuous wave optically detected magnetic resonance in diamond

We carried out a proof-of-principle demonstration of the reconstruction of a static vector magnetic field involving adjacent three nitrogen-vacancy(NV) sensors with corresponding different NV symmetry axes in a bulk diamond. By means of optical detection of the magnetic resonance(ODMR) techniques, our experiment employs the continuous wave(CW) to monitor resonance frequencies and it extracts the information of the detected field strength and polar angles with respect to each NV frame of reference. Finally, the detected magnetic field relative to a fixed laboratory reference frame was reconstructed from the information acquired by the multi-NV sensor.

TELF-PSPOC: Three-layer Ensemble Learning Framework for Predicting Student Performance of Online Courses

Virtual learning environment(VLE)MOOC provides large-scale data of resources,activities,and interactions within a course structure for predicting student performance.But it is challenging to extract and learn efficient features from student behaviors.In this paper,a three-layer ensemble learning framework for predicting student performance of online courses(TELF-PSPOC)at an early phase is proposed to analyze data collected from Open University Learning Analytics Dataset(OULAD).First,feature augmentation of student behavior is proposed to enrich current features of student performance,including pass rate and grades of all staged tests,daily clicks of online resources.Second,three-layer ensemble feature learning with heterogeneous classifiers(TEFL-HC)is proposed to benefit the integration of tree model and neural network.Compared with current two-layer ensemble learning,pretraining of features prevents overfitting while using nonlinear regression.The experiment shows that our TELF-PSPOC performs better than several baseline models.Besides,the relationship of the learning results and student behavior via VLE is further discovered.

Study of the axial density/impedance gradient composite long rod hypervelocity penetration into a four-layer Q345 target

Based on the dynamic shock response of the material and structure,the hypervelocity impact processes and mechanisms of long composite rods with axial density/impedance gradients penetration into fourlayer targets were studied through experiments and numerical simulation methods.The propagation law of the shock waves,together with the structural responses of the projectiles and targets,the formation and evolution of the fragment groups formed during the processes and their distributions were described.The damage of each target plate was quantitatively analysed by comparing the results of the experiment and numerical simulation.The results showed that the axial density/impedance gradient projectiles could decrease the impact pressure to a certain extent,and the degree of damage to the target plate decreased layer by layer when the head density/impedance of the projectile was high.When the head density/impedance of the projectile was low,the degree of target damage first increased layer by layer until the projectile was completely eroded and then it decreased.The results can provide a reference for the design and application of long rods with axial composite structure for velocities ranging from 6 to 10 Ma or greater.

Tongxinluo promotes endothelium-dependent arteriogenesis to attenuate diabetic peripheral arterial disease

BACKGROUND Peripheral arterial disease(PAD)has become one of the leading causes of disability and death in diabetic patients.Restoring blood supply to the hindlimbs,especially by promoting arteriogenesis,is currently the most effective strategy,in which endothelial cells play an important role.Tongxinluo(TXL)has been widely used for the treatment of cardio-cerebrovascular diseases and extended for diabetes-related vascular disease.AIM To investigate the effect of TXL on diabetic PAD and its underlying mechanisms.METHODS An animal model of diabetic PAD was established by ligating the femoral artery of db/db mice.Laser Doppler imaging and micro-computed tomography(micro-CT)were performed to assess the recovery of blood flow and arteriogenesis.Endothelial cell function related to arteriogenesis and cellular pyroptosis was assessed using histopathology,Western blot analysis,enzyme-linked immunosorbent assay and real-time polymerase chain reaction assays.In vitro,human vascular endothelial cells(HUVECs)and human vascular smooth muscle cells(VSMCs)were pretreated with TXL for 4 h,followed by incubation in high glucose and hypoxia conditions to induce cell injury.Then,indicators of HUVEC pyroptosis and function,HUVECVSMC interactions and the migration of VSMCs were measured.RESULTS Laser Doppler imaging and micro-CT showed that TXL restored blood flow to the hindlimbs and enhanced arteriogenesis.TXL also inhibited endothelial cell pyroptosis via the reactive oxygen species/nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3/Caspase-1/GSDMD signaling pathway.In addition,TXL restored endothelial cell functions,including maintaining the balance of vasodilation,acting as a barrier to reduce inflammation,and enhancing endothelial-smooth muscle cell interactions through the Jagged-1/Notch-1/ephrin-B2 signaling pathway.Similar results were observed in vitro.CONCLUSION TXL has a pro-arteriogenic effect in the treatment of diabetic PAD,and the mechanism may be related to the inhibition of endothelial cell pyroptosis,restoration of endothelial cell function and promotion of endothelial cell-smooth muscle cell interactions.

An Ensemble Learning Model for Early Dropout Prediction of MOOC Courses

Massive open online courses(MOOCs)have become a way of online learning across the world in the past few years.However,the extremely high dropout rate has brought many challenges to the development of online learning.Most of the current methods have low accuracy and poor generalization ability when dealing with high-dimensional dropout features.They focus on the analysis of the learning score and check result of online course,but neglect the phased student behaviors.Besides,the status of student participation at a given moment is necessarily impacted by the prior status of learning.To address these issues,this paper has proposed an ensemble learning model for early dropout prediction(ELM-EDP)that integrates attention-based document representation as a vector(A-Doc2vec),feature learning of course difficulty,and weighted soft voting ensemble with heterogeneous classifiers(WSV-HC).First,A-Doc2vec is proposed to learn sequence features of student behaviors of watching lecture videos and completing course assignments.It also captures the relationship between courses and videos.Then,a feature learning method is proposed to reduce the interference caused by the differences of course difficulty on the dropout prediction.Finally,WSV-HC is proposed to highlight the benefits of integration strategies of boosting and bagging.Experiments on the MOOCCube2020 dataset show that the high accuracy of our ELM-EDP has better results on Accuracy,Precision,Recall,and F1.

Application of magnetotactic bacteria as engineering microrobots:Higher delivery efficiency of antitumor medicine

For a significant duration,enhancing the efficacy of cancer therapy has remained a critical concern.Magnetotactic bacteria(MTB),often likened to micro-robots,hold substantial promise as a drug delivery system.MTB,classified as anaerobic,aquatic,and gram-negative microorganisms,exhibit remarkable motility and precise control over their internal biomineralization processes.This unique ability results in the formation of magnetic nanoparticles arranged along filamentous structures in a catenary fashion,enclosed within a membrane.These bacteria possess distinctive biochemical properties that facilitate their precise positioning within complex environments.By harnessing these biochemical attributes,MTB could potentially offer substantial advantages in the realm of cancer therapy.This article reviews the drug delivery capabilities of MTB in tumor treatment and explores various applications based on their inherent properties.The objective is to provide a comprehensive understanding of MTB-driven drug delivery and stimulate innovative insights in this field.

超高速撞击条件下靶体损伤区的数值模拟分析

超高速撞击问题中,靶体损伤区研究能够弥补部分实验中难以精确获取成坑形貌的问题,为撞击机理研究和数值模拟的校验提供重要依据.损伤区的数值模拟研究开展较少,主要原因是缺乏经过实验验证的损伤区判据.本文总结了已有的损伤区定量测量实验结果,发现对于同一种靶体,多种切片显微测试方法得到的损伤区深度比较吻合,这给损伤区分析提供了便利.基于iSALE程序模拟分析了累计塑性应变、损伤因子和峰值压力作为损伤区判断参数的适用性,认为TPS=0.1适合作为损伤判据;D=1可以作为损伤判据,但误差较大需谨慎使用;峰值压力不适合作为损伤判据.通过参数化分析发现,随着孔隙率增大和靶体强度增大,损伤区深度逐渐减小.

Al基含能结构材料的Johnson-Cook本构模型及失效参数研究

利用万能实验机和Hopkinson杆装置测试了Al基含能结构材料在不同温度下的静动态力学性能,分析实验结果得到了温度效应和应变率效应对材料力学性能的影响及该合金的Johnson-Cook本构模型参数.结合二维数字图像相关(DIC)方法,研究了Al基含能结构材料的失效应变与应力三轴度及温度之间的关系,得到了该合金的Johnson-Cook失效模型参数.通过平面撞击实验获得了Al基含能结构材料粒子速度和应力波波速之间的经验线性关系和该合金的Grüneisen系数.基于实验获得的材料本构关系和状态方程参数,完成了Al基含能结构材料超高速撞击多层间隔薄钢板的数值模拟,结果表明,数值模拟中靶板的毁伤模式、破孔直径及弹坑主要散布区和实验结果吻合.

An effective strategy to establish a male sterility mutant mini-library by CRISPR/Cas9-mediated knockout of anther-specific genes in rice

Male sterility(MS),characterized by functional defects in male organs or gametes,is an important agronomic trait for hybrid seed production,especially for self-pollinated crops such as rice(Oryza sativa L)(Chen and Liu,2014).Spontaneous MS mutants are rare and difficult to maintain in nature,thus limiting basicresearch and breeding.Artificial mutants are typically generated by physical,chemical,or biological mutagenesis(Wei et al,2013).Recently developed genome editing systems such as CRISPR/Cas9 allow efficient and timesaving knockout of endogenous genes at specific sites(Smith et al,2000;Moscou and Bogdanove,2009;Gasiunas et al.,2012).

International Clinical Practice Guideline of Chinese Medicine Climacteric Syndrome

Foreword International TCM Clinical Practice Guidelines˙Menopausal Syndrome was based on Diagnosis and Treatment Guidelines of Common Disease of TCM Gynaecology˙Climacteric Syndrome(standard number:ZYYXH/T 218-2012)published by the China Association of Chinese Medicine in 2012.Combining with the clinical research evidence at home and abroad in recent years,evidence classification and recommendation opinions were reached,and through expert discussion,this International TCM Clinical Practice Guidelines of Climacteric Syndrome was formed.

Multivalence-Ion Intercalation Enables Ultrahigh 1T Phase MoS_(2)Nanoflowers to Enhanced Sodium-Storage Performance

Developing rapid charging and robust electrode materials for Na-ion batteries is of considerable significance in large-scale power electricity fields.Herein,the authors have proposed a multivalenceion intercalation strategy to construct threedimensional(3D)Co-MoS2 nanoflowers with tailorable 1T/2H phase and interlayer distance.The as-formed S-Co-S covalent bonds serve as“electric bridges”to accelerate interlayer charge transfer without 1T phase degeneration during sodiation and desodiation.Quantum density functional theory(QDFT)calculations further confirm that the optimal Co-MoS2 nanoflowers possess the highest Na adsorption energy with reduced ionic diffusion barrier.Consequently,they deliver a superior sodiumstorage capacity of 351 mAh g−1 in 0.4-3.0 V even at 20 A g−1 without capacity fading at 5 A g−1 for 2000 cycles.The high electrochemical reversibility of the 1T phase in Co-MoS2,which accounts for such excellent performance,has been unveiled for the first time by in situ Raman spectra.This finding demonstrates important insights onto promoting two-dimensional(2D)nanomaterials toward rapid charging alkali-ion batteries.

Microwave hydrothermal synthesis of lanthanum oxyfluoride nanorods for photocatalytic nitrogen fixation:Effect of Pr doping

Photocatalytic fixation of nitrogen has been recognized as a green and promising strategy for ammonia synthesis under ambient conditions.However,the efficient reduction of nitrogen remains a challenge due to high activation energy of nitrogen and low utilization of solar energy.Herein,lanthanum oxyfluoride with different doping content of Pr3+(LaOF:xPr3+)upconversion nanorods were synthesized by microwave hydrothermal method.Results indicated that the doping of Pr3+generated considerable defects on the surface of LaOF which acted as the adsorption and activation center for nitrogen.Meanwhile,the Pr3+ion narrowed the band gap and broadened the light response range of LaOF because LaOF:Pr3+can upconvert visible light into ultraviolet light,which excite LaOF nanorods and improve the utilization of solar light.The doping amount of Pr3+had critical effect on the photocatalytic nitrogen fixation performance which reached as high as 180μmol·L?1·ho1 when the molar ratio of Pr3+to LaOF was optimized to be 2%.

Analysis and Prediction of Hole Penetrated in Thin Plates under Hypervelocity Impacts of Cylindrical Projectiles

The hole penetrated in thin metallic plates due to hypervelocity impacts of cylindrical projectiles was analyzed by experimental method.The projectile caused a hole-expanding effect when penetrating the target plate because of dynamic shear failure and extrusion.A new empirical model was presented to predict the perforation diameter in thin plates impacted by high-velocity cylindrical projectiles.The fitting coefficients resulted in a root-mean-square of 0.0641 and a correlation coefficient of 0.991.The errors between the predicted and the experimental values were less than 7.251%,and less than 4.705%for 93.333%cases of the dataset.The accuracy of the proposed model is much higher than that of Hill's model.Compared with historical equations,the new model is more accurate and can well describe the variations of different parameters with the normalized penetrated hole.The model takes into account the strength of materials,which contributes to the excellent results.This paper could provide important theoretical support for the analysis of the perforation process and its mechanism.

A型塞内卡病毒的病毒样颗粒的制备及其免疫原性分析

为了研制A型塞内卡病毒(Senecavirus A,SVA)的病毒样颗粒(Virus-like particles,VLPs)疫苗,以SVA田间流行毒株CH-FJ-2017结构蛋白基因序列为研究对象,构建了能够同时表达SVA的3种结构蛋白VP0、VP1和VP3的单个原核重组表达质粒pET28a-SVA-VP031。通过大肠杆菌Escherichia coli表达、亲和层析纯化和体外自组装,获得SVA VLPs。透射电子显微镜鉴定显示,SVA的3种结构蛋白在体外能够自组装成直径约25–30 nm的VLPs,并且动物免疫试验结果表明,该VLPs能够有效刺激豚鼠产生高水平的抗原特异性中和抗体。上述研究结果为SVA VLPs疫苗的研制奠定了基础。

Boosting reaction kinetics and reversibility in Mott-Schottky VS/MoS heterojunctions for enhanced lithium storage

Heterostructures have lately been recognized as a viable implement to achieve high-energy Li-ion batteries(LIBs) because the as-formed built-in electric field can greatly accelerate the charge transfer kinetics. Herein, we have constructed the Mott-Schottky heterostructured VS2/MoS2 hybrids with tailorable 1T/2H phase based on their matchable formation energy, which are made of metallic and few-layered VS2 vertically grown on MoS2 surface. The density functional theory(DFT) calculations unveil that such heterojunctions drive the rearrangement of energy band with a facilitated reaction kinetics and enhance the Li adsorption energy more than twice compared to the MoS2 surface. Furthermore, the VS2 catalytically expedites the Li–S bond fracture and meantime the enriched Mo6+ enables the sulfur anchoring toward the oriented reaction with Li+to form Li2S, synergistically enhancing the reversibility of electrochemical redox. Consequently, the as-obtained VS2/MoS2 hybrids deliver a very large specific capacity of 1273 m Ah g^-1 at 0.1 A g^-1 with 61% retention even at 5 A g^-1. It can also stabilize 100 cycles at 0.5 A g^-1 and 500 cycles at 1 A g^-1. The findings provide in-depth insights into engineering heterojunctions towards the enhancement of reaction kinetics and reversibility for LIBs.

DELLA-GRF4-mediated coordination of growth and nitrogen metabolism paves the way for a new Green Revolution

The Green Revolution （GR） based on semi-dwarf breeding has greatly increased cereal crop yields since the 1960＇s.Owing to appropriate plant height, the semi-dwarf crop plants are beneficial to increase light utilization and improve the lodging-resistance, and eventually increase yield potential （Hedden, 2003）. During the past 50 years, the worldwide application of semi-dwarf crop breeding has produced plenty of elite varieties. The characters of Green Revolution varieties （GRVs） are caused by the mutant growth-repressing genes.

Shortened snRNA promoters for efficient CRISPR/Cas-based multiplex genome editing in monocot plants

Dear Editor,CRISPR(clustered regularly interspaced short palindromic repeats)/Cas genome editing is a powerful tool for introducing specific mutations in organisms including plants.The system is composed of a nuclease such as Cas9 or Cas12a and an engineered single-guide RNA(sgRNA)incorporating a target sequence(Li et al.,2019).A Cas9/sgRNA complex recognizes its target site in the genome,resulting in a mutation at that site.

OsEDM2L mediates m^(6)A of EAT1 transcript for proper alternative splicing and polyadenylation regulating rice tapetal degradation

N^(6)-methyladenosine(m^(6)A) modification affects the post-transcriptional regulation of eukaryotic gene expression, but the underlying mechanisms and their effects in plants remain largely unknown. Here,we report that the N^(6)-adenine methyltransferase-like domain-containing protein ENHANCED DOWNY MILDEW 2-LIKE(OsEDM2 L) is essential for rice(Oryza sativa L.) anther development. The osedm2 l knockout mutant showed delayed tapetal programmed cell death(PCD) and defective pollen development. OsEDM2 L interacts with the transcription factors basic helix-loop-helix 142 and TAPETUMDEGENERATIONRETARDATIONto regulate the expression of ETERNAL TAPETUM 1(EAT1), a positive regulator of tapetal PCD. Mutation of OsEDM2 L altered the transcriptomic m^(6)A landscape, and caused a distinct m^(6)A modification of the EAT1 transcript leading to dysregulation of its alternative splicing and polyadenylation, followed by suppression of the EAT1 target genes OsAP25 and OsAP37 for tapetal PCD. Therefore, OsEDM2 L is indispensable for proper messenger RNA m^(6)A modification in rice anther development.