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Sparse Modal Decomposition Method Addressing Underdetermined Vortex-Induced Vibration Reconstruction Problem for Marine Risers

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China Ocean Engineering 2024年第2期38卷 285-296页

作者： DU Zun-feng zhu Hai-ming YU Jian-xing State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation School of Civil EngineeringTianjin UniversityTianjin 300350China

When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real risers.The problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration modes.However,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known measurements.This study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal space.In the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring.

关键词： motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing

Chemical Scissors Tailored Nano‑Tellurium with High‑Entropy Morphology for Efficient Foam‑Hydrogel‑Based Solar Photothermal Evaporators

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Nano-Micro Letters 2024年第3期16卷 149-168页

作者： Chenyang xing Zihao Li Ziao Wang Shaohui Zhang Zhongjian Xie Xi zhu Zhengchun Peng State Key Laboratory of Radio FrequencyHeterogeneous Integration Shenzhen UniversityShenzhen 518060People’s Republic of China Center for Stretchable Electronics and NanoSensors College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China School of Science and Engineering The Chinese University of Hong KongShenzhenShenzhen 518172People’s Republic of China Institute of Pediatrics Shenzhen Children’s HospitalShenzhen 518038GuangdongPeople’s Republic of China International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060People’s Republic of China

The development of tellurium(Te)-based semiconductor nanomaterials for efficient light-to-heat conversion may offer an effective means of harvesting sunlight to address global energy concerns.However,the nanosized Te(nano-Te)materials reported to date suffer from a series of drawbacks,including limited light absorption and a lack of surface structures.Herein,we report the preparation of nano-Te by electrochemical exfoliation using an electrolyzable room-temperature ionic liquid.Anions,cations,and their corresponding electrolytic products acting as chemical scissors can precisely intercalate and functionalize bulk Te.The resulting nano-Te has high morphological entropy,rich surface functional groups,and broad light absorption.We also constructed foam hydrogels based on poly(vinyl alcohol)/nano-Te,which achieved an evaporation rate and energy efficiency of 4.11 kg m^(−2)h^(−1)and 128%,respectively,under 1 sun irradiation.Furthermore,the evaporation rate was maintained in the range 2.5-3.0 kg m^(−2)h^(−1)outdoors under 0.5-1.0 sun,providing highly efficient evaporation under low light conditions.

关键词： Tellurium High entropy Electrochemical modification Solar absorption Evaporation rate

Light-controlled soft bio-microrobot

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Light(Science & Applications) 2024年第3期13卷 531-543页

作者： Jianyun Xiong xing Li Ziyi He Yang Shi Ting Pan Guoshuai zhu Dengyun Lu Hongbao Xin Guangdong Provincial Key Laboratory of Nanophotonic Manipulation Institute of NanophotonicsJinan University511443 GuangzhouChina

Micro/nanorobots hold exciting prospects for biomedical and even clinical applications due to their small size and high controllability.However,it is still a big challenge to maneuver micro/nanorobots into narrow spaces with high deformability and adaptability to perform complicated biomedical tasks.Here,we report a light-controlled soft bio-microrobots(called“Ebot”)based on Euglena gracilis that are capable of performing multiple tasks in narrow microenvironments including intestinal mucosa with high controllability,deformability and adaptability.The motion of the Ebot can be precisely navigated via light-controlled polygonal flagellum beating.Moreover,the Ebot shows highly controlled deformability with different light illumination duration,which allows it to pass through narrow and curved microchannels with high adaptability.With these features,Ebots are able to execute multiple tasks,such as targeted drug delivery,selective removal of diseased cells in intestinal mucosa,as well as photodynamic therapy.This light-controlled Ebot provides a new bio-microrobotic tool,with many new possibilities for biomedical task execution in narrow and complicated spaces where conventional tools are difficult to access due to the lack of deformability and bio-adaptability.

关键词： narrow illumination curved

An Adaptive Local Grid Nesting-based Genetic Algorithm for Multi-earth Observation Satellites' Area Target Observation

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Journal of Systems Science and Systems Engineering 2024年第2期33卷 232-258页

作者： Ligang xing Wei Xia Xiaoxuan Hu Waiming zhu Yi Wu School of Management Hefei University of TechnologyHefei 230009China Key Laboratory of Process Optimization and Inteligent Decision-making Ministry of EducationHefei 230009China Intelligent Interconnected Systems Laboratory of Anhui Province Hefei 230009China

The Scheduling of the Multi-EOSs Area Target Observation(SMEATO)is an EOS resource schedul-ing problem highly coupled with computational geometry.The advances in EOS technology and the ex-pansion of wide-area remote sensing applications have increased the practical significance of SMEATO.In this paper,an adaptive local grid nesting-based genetic algorithm(ALGN-GA)is proposed for developing SMEATO solutions.First,a local grid nesting(LGN)strategy is designed to discretize the target area into parts,so as to avoid the explosive growth of calculations.A genetic algorithm(GA)framework is then used to share reserve information for the population during iterative evolution,which can generate high-quality solutions with low computational costs.On this basis,an adaptive technique is introduced to determine whether a local region requires nesting and whether the grid scale is sufficient.The effectiveness of the proposed model is assessed experimentally with nine randomly generated tests at different scales.The results show that the ALGN-GA offers advantages over several conventional algorithms in 88.9%of instances,especially in large-scale instances.These fully demonstrate the high efficiency and stability of the ALGN-GA.

关键词： Multi-EOSs scheduling area target observation adaptive genetic algorithm local grid nesting

CrossFormer Embedding DeepLabv3+ for Remote Sensing Images Semantic Segmentation

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Computers, Materials & Continua 2024年第4期79卷 1353-1375页

作者： Qixiang Tong Zhipeng zhu Min Zhang Kerui Cao Haihua xing School of Information Science and Technology Hainan Normal UniversityHaikou571158China

High-resolution remote sensing image segmentation is a challenging task. In urban remote sensing, the presenceof occlusions and shadows often results in blurred or invisible object boundaries, thereby increasing the difficultyof segmentation. In this paper, an improved network with a cross-region self-attention mechanism for multi-scalefeatures based onDeepLabv3+is designed to address the difficulties of small object segmentation and blurred targetedge segmentation. First,we use CrossFormer as the backbone feature extraction network to achieve the interactionbetween large- and small-scale features, and establish self-attention associations between features at both large andsmall scales to capture global contextual feature information. Next, an improved atrous spatial pyramid poolingmodule is introduced to establish multi-scale feature maps with large- and small-scale feature associations, andattention vectors are added in the channel direction to enable adaptive adjustment of multi-scale channel features.The proposed networkmodel is validated using the PotsdamandVaihingen datasets. The experimental results showthat, compared with existing techniques, the network model designed in this paper can extract and fuse multiscaleinformation, more clearly extract edge information and small-scale information, and segment boundariesmore smoothly. Experimental results on public datasets demonstrate the superiority of ourmethod compared withseveral state-of-the-art networks.

关键词： Semantic segmentation remote sensing multiscale self-attention

Divergent defluorocarboxylation of α-CF_(3) alkenes with formate via photocatalyzed selective mono-or triple C-F bond cleavage

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Science China Chemistry 2024年第1期67卷 368-373页

作者： xing-Yu Wang Pei Xu Wen-Wen Liu Hao-Qiang Jiang Song-Lei zhu Dong Guo Xu zhu Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy School of PharmacyXuzhou Medical UniversityXuzhou 22100China

Unprecedented divergent synthesis of gem-difluorovinylacetic acid and glutaric acid derivatives fromα-CF_(3)alkenes with formate as the carbonyl source was disclosed.The reaction can undergo selective mono-or triple C-F bond cleavage by simply switching the photocatalyst and hydrogen atom transfer(HAT)catalyst under visible-light-induced conditions at room temperature.Foramte acts as both the C1 source and the reductant through the generation of CO_(2)^(·-)species,which underwent Giese radical addition to electron-deficient alkenes to trigger the consecutive C-F bond cleavage and carboxylation process.

关键词： C-F bond activation defluorocarboxylation carbon dioxide radical anion visible light

Robotic versus laparoscopic surgery for sporadic benign insulinoma:Short-and long-term outcomes

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 399-405页

作者： zhu-Zeng Yin Yuan-xing Gao Zhi-Ming Zhao Ming-Gen Hu Wen-Bo Tang Rong Liu Faculty of Hepato-Pancreato-Biliary Surgery The First Medical CenterChinese PLA General HospitalBeijing 100853China Institute of Hepatobiliary Surgery of Chinese PLA Beijing 100853China Key Laboratory of Digital Hepatobiliary Surgery of Chinese PLA Beijing 100853China

Background:Minimally invasive surgery is the optimal treatment for insulinoma.The present study aimed to compare short-and long-term outcomes of laparoscopic and robotic surgery for sporadic benign insulinoma.Methods:A retrospective analysis of patients who underwent laparoscopic or robotic surgery for insulinoma at our center between September 2007 and December 2019 was conducted.The demographic,perioperative and postoperative follow-up results were compared between the laparoscopic and robotic groups.Results:A total of 85 patients were enrolled,including 36 with laparoscopic approach and 49 with robotic approach.Enucleation was the preferred surgical procedure.Fifty-nine patients(69.4%)underwent enucleation;among them,26 and 33 patients underwent laparoscopic and robotic surgery,respectively.Robotic enucleation had a lower conversion rate to laparotomy(0 vs.19.2%,P=0.013),shorter operative time(102.0 vs.145.5 min,P=0.008)and shorter postoperative hospital stay(6.0 vs.8.5 d,P=0.002)than laparoscopic enucleation.There were no differences between the groups in terms of intraoperative blood loss,the rates of postoperative pancreatic fistula and complications.After a median follow-up of 65 months,two patients in the laparoscopic group developed a functional recurrence and none of the patients in the robotic group had a recurrence.Conclusions:Robotic enucleation can reduce the conversion rate to laparotomy and shorten operative time,which might lead to a reduction in postoperative hospital stay.

关键词： Robotic surgical procedures Laparoscopy Insulinoma Enucleation Pancreatectomy

Ancient dormant virus remnant ERVW-1 drives ferroptosis via degradation of GPX4 and SLC3A2 in schizophrenia

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Virologica Sinica 2024年第1期39卷 31-43页

作者： Dongyan Zhang Xiulin Wu xing Xue Wenshi Li Ping Zhou Zhao Lv Kexin Zhao Fan zhu State Key Laboratory of Virology and Department of Medical Microbiology School of Basic Medical SciencesWuhan UniversityWuhan430071China Hubei Province Key Laboratory of Allergy&Immunology Wuhan UniversityWuhan430071China

Human endogenous retroviruses(HERVs)are remnants of retroviral infections in human germline cells from millions of years ago.Among these,ERVW-1(also known as HERV-W-ENV,ERVWE1,or ENVW)encodes the envelope protein of the HERV-W family,which contributes to the pathophysiology of schizophrenia.Additionally,neuropathological studies have revealed cell death and disruption of iron homeostasis in the brains of individuals with schizophrenia.Here,our bioinformatics analysis showed that differentially expressed genes in the human prefrontal cortex RNA microarray dataset(GSE53987)were mainly related to ferroptosis and its associated pathways.Clinical data demonstrated significantly lower expression levels of ferroptosis-related genes,particularly Glutathione peroxidase 4(GPX4)and solute carrier family 3 member 2(SLC3A2),in schizophrenia patients compared to normal controls.Further in-depth analyses revealed a significant negative correlation between ERVW-1 expression and the levels of GPX4/SLC3A2 in schizophrenia.Studies indicated that ERVW-1 increased iron levels,malondialdehyde(MDA),and transferrin receptor protein 1(TFR1)expression while decreasing glutathione(GSH)levels and triggering the loss of mitochondrial membrane potential,suggesting that ERVW-1 can induce ferroptosis.Ongoing research has shown that ERVW-1 reduced the expression of GPX4 and SLC3A2 by inhibiting their promoter activities.Moreover,Ferrostatin-1(Fer-1),the ferroptosis inhibitor,reversed the iron accumulation and mitochondrial membrane potential loss,as well as restored the expressions of ferroptosis markers GSH,MDA,and TFR1 induced by ERVW-1.In conclusion,ERVW-1 could promote ferroptosis by downregulating the expression of GPX4 and SLC3A2,revealing a novel mechanism by which ERVW-1 contributes to neuronal cell death in schizophrenia.

关键词： ERVW-1 Glutathione peroxidase 4(GPX4) Solute carrier family 3 member 2(SLC3A2) Ferroptosis Schizophrenia

Mapping out the reaction network of humin formation at the initial stage of fructose dehydration in water

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Green Energy & Environment 2024年第6期9卷 1016-1026页

作者： xing Fu Yexin Hu Ping Hu Hui Li Shuguang Xu Liangfang zhu Changwei Hu Key Laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengduSichuan610064China State Key Laboratory of Southwestern Chinese Medicine Resources Innovative Institute of Chinese Medicine and PharmacyChengdu University of Traditional Chinese MedicineChengduSichuan611137China

The formation of humins hampers the large-scale production of 5-hydroxymethylfurfural(HMF)in biorefinery.Here,a detailed reaction network of humin formation at the initial stage of fructose-to-HMF dehydration in water is delineated by combined experimental,spectroscopic,and theoretical studies.Three bimolecular reaction pathways to build up soluble humins are demonstrated.That is,the intermolecular etherification of β-furanose at room temperature initiates the C12 path,whereas the C-C cleavage of a-furanose at 130-150℃ leads to C11 path,and that of open-chain fructose at 180℃ to C11' path.The successive intramolecular dehydrations and condensations of the as-formed bimolecular intermediates lead to three types of soluble humins.We show that the C12 path could be restrained by using HCl or AlCl_(3) catalyst,and both the C12 and C110 paths could be effectively inhibited by adding THF as a co-solvent or accelerating heating rate via microwave heating.

关键词： Carbohydrates 5-hydroxymethylfurfural Reaction network Soluble humins Tautomer