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Enzyme-driven Nanorobots Walking Along Predesigned Tracks on the DNA Origami for Cargo Transport and Catalysis

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Chemical Research in Chinese Universities 2024年第2期40卷 333-342页

作者： NIE Cunpeng MA Tianran CHEN Tingting chu xia State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha410082P.R.China

In molecular engineering,designing and synthesizing molecular machines with capable of performing complex tasks,remains a formidable *** is an excellent candidate for building molecular robots because it is highly ***,we present an artificial nanorobot,in which a DNA cube serves as the inert‘body’,and nucleic acid catalysts based on an enzymatic nicking reaction act as the‘legs’for *** nanorobot can execute a series of actions,such as‘start’,‘turn’,and‘stop’when it walks along a predefined *** performance could be confirmed and monitored by using an atomic force microscope(AFM)and fluorescence *** by biological machines,we artificially designed a series of specialized tasks that combined walking with control of cargo transport and ***-time fluorescence kinetics curves provide monitoring signals for cargo transport and catalytic *** work can enrich the toolbox of DNA machinery and has great potential for engineering molecular nanofactories.

关键词： DNA origami DNA nanorobot Controlled cargo transport DNAzyme catalysis

Bi^(3+)-activated dual-wavelength emitting phosphors toward effective optical thermometry

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Chinese Chemical Letters 2024年第3期35卷 486-492页

作者： yu Xue yuqi Chen Guixian Li Weixi xia Qinan Mao Lang Pei Meijiao Liu Liang chu Jiasong Zhong Center of Advanced Optoelectronic Materials College of Materials and Environmental EngineeringHangzhou Dianzi UniversityHangzhou 310018China College of Electronics and Information Hangzhou Dianzi UniversityHangzhou 310018China Department of Chemistry Zhejiang Sci-Tech UniversityHangzhou 310018China

Optical thermometry as an important local temperature-sensing technique,has received increasing attention in scientific and industrial ***,it is still a big challenge to develop luminescent materials with self-activated dual-wavelength emissions toward high-sensitivity optical ***,a novel ratiometric thermometric strategy of Bi^(3+)-activated dual-wavelength emission band was realized in the same lattice position with two local electronic states of La_(3)Sb_(1-x)Ta_xO_(7):Bi^(3+)(0≤x≤1.0)materials based on the different temperature-dependent emission behaviors,benefiting from the highlysensitive and regulable emission to the coordination environment of Bi^(3+).The structural and spectral results demonstrate that the emission tremendously shifted from green to blue with 68 nm and the intensity was enhanced 2.6 ***,the visual dual-wavelength emitting from two emission centers was presented by increasing the Ta^(5+)substitution concentration to 20%or 25%,mainly originating from the two local electronic states around the Bi^(3+)emission ***,the dual-wavelength with different thermal-quenching performance provided high-temperature sensitivity and good discrimination signals for optical thermometry in the range between 303 and 493 *** maximum relative sensitivity reached 2.64%/K(La_(3)Sb_(0.8)Ta_(0.2)O_(7):0.04Bi^(3+)@383 K)and 1.91%/K(La_(3)Sb_(0.75)Ta_(0.25)O_(7):0.04Bi^(3+)@388 K).This work reveals a rational design strategy of different local electronic states around the singledoping multiple emission centers towards practical applications,such as luminescence thermometry and white LED lighting.

关键词： Dual-wavelength emitting Cationic substitution Two local electronic states Optical thermometry Bi^(3+)-doped phosphor

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On Stability Discrimination of Limit Cycles for Piecewise Smooth Systems

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1785-1803页

作者： Mao An HAN xia.yu ZHOU School of Mathematical Sciences Zhejiang Normal UniversityJinhua321004P.R.China

This paper is concerned with the problem of stability discrimination of limit cycles for piecewise smooth *** first establish the Poincaré map near a periodic orbit,and deduce the first order derivative of the map for general piecewise smooth systems on the ***,we obtain a sufficient condition for determining the stability of limit cycles for these systems.

关键词： Piecewise smooth system limit cycle stability

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Evolution of inner wall wrinkle defects in the sinking zone of a thick-walled steel tube during radial forging

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Advances in Manufacturing 2024年第2期12卷 396-408页

作者： yu-Zhao Yang Cheng Xu Li-xia Fan School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094People’s Republic of China

An axial wrinkle defect was observed in the inner wall of the sinking zone of a thick-wall steel tube processed by cold radial *** can evolve into *** present study focuses on the evolution of wrinkles and the effects of process parameters on them using a three-dimensional radial forging process finite element model,radial forging experiments,and surface morphology *** results indicated that the vertical section angle of the hammer die and the size of the tube blank significantly affect the evolution of *** height-to-width ratioλwas introduced to describe the morphology of *** had an approximately linear relationship with the radius reduction in the sinking *** was a linear correlation between the growth slope ofλand the axial to circumferential strain ratio|εr/εθ|,which can predict theλunder few process *** the 30SiMn2MoVA steel,at the junction of the forging and sinking zones,the threshold ofλof the wrinkle that can evolve into a fissure is approximately 1.123.

关键词： Radial forging Inner wall Wrinkle defects Evolution Sinking zone

Towards imbalanced motion:part-decoupling network for video portrait segmentation

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Science China(Information Sciences) 2024年第7期67卷 197-210页

作者： Tianshu yu Changqun xia Jia LI State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and EngineeringBeihang University Peng Cheng Laboratory

Video portrait segmentation(VPS), aiming at segmenting prominent foreground portraits from video frames, has received much attention in recent years. However, the simplicity of existing VPS datasets leads to a limitation on extensive research of the task. In this work, we propose a new intricate large-scale multi-scene video portrait segmentation dataset MVPS consisting of 101 video clips in 7 scenario categories,in which 10843 sampled frames are finely annotated at the pixel level. The dataset has diverse scenes and complicated background environments, which is the most complex dataset in VPS to our best *** the observation of a large number of videos with portraits during dataset construction, we find that due to the joint structure of the human body, the motion of portraits is part-associated, which leads to the different parts being relatively independent in motion. That is, the motion of different parts of the portraits is imbalanced. Towards this imbalance, an intuitive and reasonable idea is that different motion states in portraits can be better exploited by decoupling the portraits into parts. To achieve this, we propose a part-decoupling network(PDNet) for VPS. Specifically, an inter-frame part-discriminated attention(IPDA)module is proposed which unsupervisedly segments portrait into parts and utilizes different attentiveness on discriminative features specified to each different part. In this way, appropriate attention can be imposed on portrait parts with imbalanced motion to extract part-discriminated correlations, so that the portraits can be segmented more accurately. Experimental results demonstrate that our method achieves leading performance with the comparison to state-of-the-art methods.

关键词： video portrait segmentation imbalanced motion unsupervised part decoupling motion correlation inter-frame attention

Perception field based imitation learning for unlabeled multi-agent pathfinding

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Science China(Information Sciences) 2024年第5期67卷 115-135页

作者： Wenjie chu Ailun yu Wei ZHANG Haiyan ZHAO Zhi JIN School of Computer Science Peking University Key Laboratory of High-Confidence Software Technologies (Peking University) Ministry of Education

This paper proposes an imitation learning method to learn a universal agent policy for unlabeled multi-agent pathfinding(unlabeled MAPF) in grid environments. The method transforms the unlabeled MAPF problem into a series of temporal-independent homogeneous classification problems for each *** on this transformation, a neural network is designed to imitate a distance-optimal expert *** neural network consists of two successive modules: perception field learner and field integrating *** former refines and encodes the current system state into a perception field for each agent by combining a set of learnable field-generating functions. The latter takes an agent's perception field as input and decides the agent's next action based on a triplet cross-attention mechanism. We evaluate our method on a diverse set of unlabeled MAPF tasks. Compared with state-of-the-art counterparts, the experimental results manifest the superiority of the proposed method in both generalization ability and scalability.

关键词： unlabeled multi-agent pathfinding perception field triplet cross-attention multi-agent imitation learning learning-based planning

Developing risk models and subtypes of autophagy-associated LncRNAs for enhanced prognostic prediction and precision in therapeutic approaches for liver cancer patients

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Oncology Research 2024年第4期32卷 703-716页

作者： LU ZHANG JINGUO chu yuSHAN yu Department of General Practice The First Affiliated Hospital of Ningbo UniversityNingboChina

Background:Limited research has been conducted on the influence of autophagy-associated long non-coding RNAs(ARLncRNAs)on the prognosis of hepatocellular carcinoma(HCC).Methods:We analyzed 371 HCC samples from TCGA,identifying expression networks of ARLncRNAs using autophagy-related *** for prognostically relevant ARLncRNAs involved univariate Cox regression,Lasso regression,and multivariate Cox regression.A Nomogram was further employed to assess the reliability of Riskscore,calculated from the signatures of screened ARLncRNAs,in predicting ***,we compared drug sensitivities in patient groups with differing risk levels and investigated potential biological pathways through enrichment analysis,using consensus clustering to identify subgroups related to ***:The screening process identified 27 ARLncRNAs,with 13 being associated with HCC ***,a set of signatures comprising 8 ARLncRNAs was successfully constructed as independent prognostic factors for *** in the high-risk group showed very poor prognoses in most clinical *** Riskscore was closely related to immune cell scores,such as macrophages,and the DEGs between different groups were implicated in metabolism,cell cycle,and mitotic ***,high-risk group patients demonstrated a significantly lower IC50 for Paclitaxel,suggesting that Paclitaxel could be an ideal treatment for those at elevated risk for *** further identified C2 as the Paclitaxel subtype,where patients exhibited higher Riskscores,reduced survival rates,and more severe clinical ***:The 8 signatures based on ARLncRNAs present novel targets for prognostic prediction in *** drug candidate Paclitaxel may effectively treat HCC by impacting ARLncRNAs *** the identification of ARLncRNAsrelated isoforms,these results provide valuable insights for clinical exploration of autophagy mechanisms in HCC pathogenesis and offer potential av

关键词： Autophagy Hepatocellular carcinoma(HCC) Prognosis Precision medicine Paclitaxel

Reliability analysis of carbon fiber rod-reinforced umbilical cable under tension using an improved sampling method

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Petroleum Science 2024年第4期21卷 2769-2778页

作者： yu Zhang Hong-yu Zhang Ran xia Si-Ao Jiang Fang Wang College of Safety and Ocean Engineering China University of Petroleum China Academy of Aerospace Aerodynamics China Aerospace Science and Technology Group College of Engineering Science and Technology Shanghai Ocean University

The umbilical cable is a vital component of subsea production systems that provide power, chemical agents, control signals et al., and its requirement for reliability is exceedingly high. However, as the umbilical cable is a composite structure comprising multiple functional units, the reliability analysis of such cables involves numerous parameters that can impact calculation efficiency. In this paper, the reliability analysis of a new kind of umbilical cable with carbon fiber rod under tension is analyzed. The global dynamic analytical model is first established to determine the maximum tension load, then the local analytical model of umbilical cable including each unit are constructed by finite element method(FEM). Based on the mechanical analytical model, the reliability of umbilical cable under tension load is studied using response surface method(RSM) and Monte Carlo method. During the calculation process, a new tangent plane sampling method to calculate the response surface function(RSF) is proposed in this paper, which could make sampling points faster come close to the RSF curve, and it is proved that the calculation efficiency increases about 33% comparing with traditional method.

关键词： Umbilical cable Carbon fiber rod Failure analysis Response surface method Reliability

Candy or poison: Plant metabolites as swing factors against microbes

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Molecular Plant 2024年第9期17卷 1341-1343页

作者： Liyuan Wang yu xia Yingnan Hou Shanghai Collaborative Innovation Center of Agri-Seeds School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240China

Plant metabolites play crucial roles in plant-microbe interactions,influencing compatibility with different microbial species and modulating both symbiotic and pathogenic *** synthesize two categories of metabolites:primary and secondary metabolites,each serving specific functions in plant physiology and *** metabolites,including sugars,lipids,nucleotides,amino acids,and organic acids,are essential for plant growth and ***,these metabolites also serve as nutrient sources for *** invasion of devastating pathogens relies heavily on their ability to effectively acquire primary metabolites from host *** instance,transcriptional activator-like effectors from Xanthomonas and Ralstonia are known to trigger the transcription of OsSWEET genes,which encode sugar transporters.

关键词： invasion sugar Plant