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Application of Three-Dimensional Visual Simulation in Tidal Defense Engineering 被引量:1
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作者 钟登华 杨斌 +2 位作者 李文倩 刘东海 佟大威 《Transactions of Tianjin University》 EI CAS 2013年第1期1-9,共9页
Any tidal defense engineering involves the collection and analysis of massive information about engineering structures and their surrounding environment. Traditional method, which is carried out mainly by means of two... Any tidal defense engineering involves the collection and analysis of massive information about engineering structures and their surrounding environment. Traditional method, which is carried out mainly by means of twodimensional drawings and textures, is not efficient and intuitive enough to analyze the whole project and reflect its spatial relationship. Three-dimensional visual simulation provides an advanced technical means of solving this problem. In this paper, triangular irregular network (TIN) model simplified by non-uniform rational B-splines (NURBS) technique was used to establish the digital terrain model (DTM) of a super large region. Simulation of dynamic water surface was realized by combining noise function with sine wave superposition method. Models of different objects were established with different modeling techniques according to their characteristics. Application of texture mapping technology remarkably improved the authenticity of the models. Taking the tidal defense engineering in the new coastal region of Tianjin as a case study, three-dimensional visual simulation and dynamic roaming of the study area were realized, providing visual analysis and visible demonstration method for the management and emergency decision-making associated with construction. 展开更多
关键词 tidal defense engineering three-dimensional visual simulation simulation modeling
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Exogenous melatonin enhances heat stress tolerance in sweetpotato by modulating antioxidant defense system,osmotic homeostasis and stomatal traits 被引量:1
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作者 Sunjeet Kumar Rui Yu +5 位作者 Yang Liu Yi Liu Mohammad Nauman Khan Yonghua Liu Mengzhao Wang Guopeng Zhu 《Horticultural Plant Journal》 2025年第1期431-445,共15页
Heat stress hinders the growth and productivity of sweetpotato plants,predominantly through oxidative damage to cellular membranes.Therefore,the development of efficient approaches for mitigating heat-related impairme... Heat stress hinders the growth and productivity of sweetpotato plants,predominantly through oxidative damage to cellular membranes.Therefore,the development of efficient approaches for mitigating heat-related impairments is essential for the long-term production of sweetpotatoes.Melatonin has been recognised for its capacity to assist plants in dealing with abiotic stress conditions.This research aimed to investigate how different doses of exogenous melatonin influence heat damage in sweetpotato plants.Heat stress drastically affected shoot and root fresh weight by 31.8 and 44.5%,respectively.This reduction resulted in oxidative stress characterised by increased formation of hydrogen peroxide(H_(2)O_(2))by 804.4%,superoxide ion(O_(2)^(·-))by 211.5%and malondialdehyde(MDA)by 234.2%.Heat stress also reduced chlorophyll concentration,photosystemⅡefficiency(F_v/F_m)by 15.3%and gaseous exchange.However,pre-treatment with 100μmol L^(-1)melatonin increased growth and reduced oxidative damage to sweetpotato plants under heat stress.In particular,melatonin decreased H_(2)O_(2),O_(2)^(·-)and MDA by 64.8%,42.7%and 38.2%,respectively.Melatonin also mitigated the decline in chlorophyll levels and improved stomatal traits,gaseous exchange and F_(v)/F_(m)(13%).Results suggested that the favorable outcomes of melatonin treatment can be associated with elevated antioxidant enzyme activity and an increase in non-enzymatic antioxidants and osmo-protectants.Overall,these findings indicate that exogenous melatonin can improve heat stress tolerance in sweetpotatoes.This stu dy will assist re searchers in further investigating how melatonin makes sweetpotatoes more resistant to heat stress. 展开更多
关键词 SWEETPOTATO Heat stress MELATONIN Oxidative damage Antioxidant defense system Stomatal traits
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Global Mapping of Three-Dimensional Urban Structures Reveals Escalating Utilization in the Vertical Dimension and Pronounced Building Space Inequality 被引量:1
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作者 Xiaoping Liu Xinxin Wu +6 位作者 Xuecao Li Xiaocong Xu Weilin Liao Limin Jiao Zhenzhong Zeng Guangzhao Chen Xia Li 《Engineering》 2025年第4期86-99,共14页
Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significan... Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significant gap in detailed and consistent data on 3D building space structures with global coverage due to the challenges inherent in the data collection and model calibration processes.In this study,we constructed a global urban structure(GUS-3D)dataset,including building volume,height,and footprint information,at a 500 m spatial resolution using extensive satellite observation products and numerous reference building samples.Our analysis indicated that the total volume of buildings worldwide in2015 exceeded 1×10^(12)m^(3).Over the 1985 to 2015 period,we observed a slight increase in the magnitude of 3D building volume growth(i.e.,it increased from 166.02 km3 during the 1985–2000 period to 175.08km3 during the 2000–2015 period),while the expansion magnitudes of the two-dimensional(2D)building footprint(22.51×10^(3) vs 13.29×10^(3)km^(2))and urban extent(157×10^(3) vs 133.8×10^(3)km^(2))notably decreased.This trend highlights the significant increase in intensive vertical utilization of urban land.Furthermore,we identified significant heterogeneity in building space provision and inequality across cities worldwide.This inequality is particularly pronounced in many populous Asian cities,which has been overlooked in previous studies on economic inequality.The GUS-3D dataset shows great potential to deepen our understanding of the urban environment and creates new horizons for numerous 3D urban studies. 展开更多
关键词 three-dimensional Global mapping Building volume Building height Building space inequality
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Three-dimensional line-of-sight-angle-constrained leader-following cooperative interception guidance law with prespecified impact time 被引量:2
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作者 Hao YOU Xinlong CHANG Jiufen ZHAO 《Chinese Journal of Aeronautics》 2025年第1期491-506,共16页
To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D lea... To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D leader-following cooperative interception guidance law.First,in the LOS direction of the leader,an impact time-controlled guidance law is derived based on the fixed-time stability theory,which enables the leader to complete the interception task at a prespecified impact time.Next,in the LOS direction of the followers,by introducing a time consensus tracking error function,a fixed-time consensus tracking guidance law is investigated to guarantee the consensus tracking convergence of the time-to-go.Then,in the direction normal to the LOS,by combining the designed global integral sliding mode surface and the second-order Sliding Mode Control(SMC)theory,an innovative 3D LOS-angle-constrained interception guidance law is developed,which eliminates the reaching phase in the traditional sliding mode guidance laws and effectively saves energy consumption.Moreover,it effectively suppresses the chattering phenomenon while avoiding the singularity issue,and compensates for unknown interference caused by target maneuvering online,making it convenient for practical engineering applications.Finally,theoretical proof analysis and multiple sets of numerical simulation results verify the effectiveness,superiority,and robustness of the investigated guidance law. 展开更多
关键词 three-dimensional cooperative interception Leader-following missiles Prespecified impact time LOS-angle-constrained Fixed-time stability Global integral sliding mode
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Three-dimensional models:from cell culture to Patient-Derived Organoid and its application to future liposarcoma research
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作者 SAYUMI TAHARA SYDNEY RENTSCH +4 位作者 FERNANDA COSTAS CASAL DE FARIA PATRICIA SARCHET ROMA KARNA FEDERICA CALORE RAPHAEL E.POLLOCK 《Oncology Research》 SCIE 2025年第1期1-13,共13页
Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma ... Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma pathobiology.Conventional cell culture-based research(2D cell culture)is still playing a pivotal role,while several shortcomings have been recently under discussion.In vivo,mouse models are usually adopted for pre-clinical analyses with expectations to overcome the issues of 2D cell culture.However,they do not fully recapitulate human dedifferentiated liposarcoma(DDLPS)characteristics.Therefore,three-dimensional(3D)culture systems have been the recent research focus in the cell biology field with the expectation to overcome at the same time the disadvantages of 2D cell culture and in vivo animal models and fill in the gap between them.Given the liposarcoma rarity,we believe that 3D cell culture techniques,including 3D cell cultures/co-cultures,and Patient-Derived tumor Organoids(PDOs),represent a promising approach to facilitate liposarcoma investigation and elucidate its molecular mechanisms and effective therapy development.In this review,we first provide a general overview of 3D cell cultures compared to 2D cell cultures.We then focus on one of the recent 3D cell culture applications,Patient-Derived Organoids(PDOs),summarizing and discussing several PDO methodologies.Finally,we discuss the current and future applications of PDOs to sarcoma,particularly in the field of liposarcoma. 展开更多
关键词 Cell culture LIPOSARCOMA Patient-Derived Organoid(PDO) SPHEROID three-dimensional(3D)cell culture
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Glasses-free three-dimensional laparoscopic systems in oncologic surgery:Innovation or equivalence?
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作者 Gustavo Eder González Alvarez Christian Ramírez Sánchez +3 位作者 Melissa Martínez Nieto Mario A Alarcón-Sánchez Juan JoséVarela-Hernández Sarah M LomelíMartínez 《World Journal of Gastrointestinal Surgery》 2025年第11期6-11,共6页
The development of minimally invasive surgery has transformed the management of gastrointestinal cancer.Notably,three-dimensional visualization systems have increased surgical precision.This editorial discusses a rece... The development of minimally invasive surgery has transformed the management of gastrointestinal cancer.Notably,three-dimensional visualization systems have increased surgical precision.This editorial discusses a recent study by Shen and Zhang,which compared the clinical applications of naked-eye threedimensional laparoscopic systems vs traditional optical systems in radical surgery for gastric and colorectal cancer.Both systems appeared to yield comparable surgical and oncological outcomes in terms of safety parameters,operating times,and quality of lymph node dissection.However,the spectacle-free system’s technical and logistical limitations hindered its effects on the surgical team’s overall competency.This editorial examines the authors’findings within the broader context of the evolution of oncologic laparoscopy,discusses the relevance of the results in light of the current literature,and proposes future research directions focused on multicenter validation,comprehensive ergonomic analysis,and technological advancements aimed at enhancing intraoperative collaboration.As technology continues to evolve,clinical implementation of new methods must be supported by robust scientific evidence and standardized criteria,to ensure tangible improvements in efficiency,safety,and oncologic outcomes. 展开更多
关键词 Autostereoscopic three-dimensional technology Laparoscopic surgery three-dimensional laparoscopy Twodimensional laparoscopy Oncologic surgery
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A Dynamic Deceptive Defense Framework for Zero-Day Attacks in IIoT:Integrating Stackelberg Game and Multi-Agent Distributed Deep Deterministic Policy Gradient
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作者 Shigen Shen Xiaojun Ji Yimeng Liu 《Computers, Materials & Continua》 2025年第11期3997-4021,共25页
The Industrial Internet of Things(IIoT)is increasingly vulnerable to sophisticated cyber threats,particularly zero-day attacks that exploit unknown vulnerabilities and evade traditional security measures.To address th... The Industrial Internet of Things(IIoT)is increasingly vulnerable to sophisticated cyber threats,particularly zero-day attacks that exploit unknown vulnerabilities and evade traditional security measures.To address this critical challenge,this paper proposes a dynamic defense framework named Zero-day-aware Stackelberg Game-based Multi-Agent Distributed Deep Deterministic Policy Gradient(ZSG-MAD3PG).The framework integrates Stackelberg game modeling with the Multi-Agent Distributed Deep Deterministic Policy Gradient(MAD3PG)algorithm and incorporates defensive deception(DD)strategies to achieve adaptive and efficient protection.While conventional methods typically incur considerable resource overhead and exhibit higher latency due to static or rigid defensive mechanisms,the proposed ZSG-MAD3PG framework mitigates these limitations through multi-stage game modeling and adaptive learning,enabling more efficient resource utilization and faster response times.The Stackelberg-based architecture allows defenders to dynamically optimize packet sampling strategies,while attackers adjust their tactics to reach rapid equilibrium.Furthermore,dynamic deception techniques reduce the time required for the concealment of attacks and the overall system burden.A lightweight behavioral fingerprinting detection mechanism further enhances real-time zero-day attack identification within industrial device clusters.ZSG-MAD3PG demonstrates higher true positive rates(TPR)and lower false alarm rates(FAR)compared to existing methods,while also achieving improved latency,resource efficiency,and stealth adaptability in IIoT zero-day defense scenarios. 展开更多
关键词 Industrial internet of things zero-day attacks Stackelberg game distributed deep deterministic policy gradient defensive spoofing dynamic defense
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Caterpillar feeding drives patterns of induced defenses and herbivore resistance in wild Pinus tabuliformis
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作者 Tianhua Sun Guona Zhou +4 位作者 Yanan Zhao Suhong Gao Jie Liu Junxia Liu Baojia Gao 《Journal of Forestry Research》 2025年第1期391-411,共21页
The defense mechanisms induced in wild Chinese pine(Pinus tabuliformis)in response to herbivores are not well characterized,especially in the field.To address this knowledge gap,we established a biological model syste... The defense mechanisms induced in wild Chinese pine(Pinus tabuliformis)in response to herbivores are not well characterized,especially in the field.To address this knowledge gap,we established a biological model system to evaluate proteome variations in pine needles after feeding by the Chinese pine caterpillar(Dendrolimus tabulaeformis),a major natural enemy and dominant herbivore.Quantitative tandem mass tag(TMT)proteomics and bioinformatics were utilized to systematically identify differentially abundant proteins implicated in the induced defense response of Chinese pine.We validated key protein changes using parallel reaction monitoring(PRM)technology.Pathway analysis revealed that the induced defenses involved phenylpropanoid,coumarin,and flavonoid biosynthesis,among other processes.To elucidate the regulatory patterns underlying pine resistance,we determined the activities of defense enzymes and levels of physiological and biochemical compounds.In addition,the expression of upstream genes for key proteins was validated by qRT-PCR.Our results provide new molecular insights into the induced defense mechanisms in Chinese pine against this caterpillar in the field.A better understanding of these defense strategies will inform efforts to breed more-resistant pine varieties. 展开更多
关键词 Pinus tabuliformis Dendrolimus tabulaeformis PROTEOMICS Induced defensive responses
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Effects of nitrate(NO_(3)^(−))stress-induced exacerbated cadmium(Cd^(2+))toxicity on the inflammatory response,oxidative defense,and apoptosis in juvenile Japanese flounder(Paralichthys olivaceus)
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作者 Jiachen Yu Jie Lian +6 位作者 Yingying Wan Xiangyuan Li Pengfei Liu Qing Ji Suyue Zhou Nianhao Zheng Xingqiang Wang 《Journal of Environmental Sciences》 2025年第6期535-548,共14页
Due to the discharge of industrialwastewater,urban domestic sewage,and intensive marine aquaculture tailwater,nitrate(NO_(3)^(−))pollution has emerged as a significant issue in offshore waters.Nitrate pollution affect... Due to the discharge of industrialwastewater,urban domestic sewage,and intensive marine aquaculture tailwater,nitrate(NO_(3)^(−))pollution has emerged as a significant issue in offshore waters.Nitrate pollution affects aquatic life and may interact with other pollutants,leading to comprehensive toxicity.Cadmium(Cd^(2+))is the most widespread metal contaminant,adversely affecting aquatic life in the coastal waters of China.Despite this,few studies have focused on the synergistic toxicity of NO_(3)^(−)and Cd^(2+)in marine organisms.This study conducted a 30-day exposure experiment on marine Japanese flounder(Paralichthys olivaceus)to explore the synergistic toxicity of NO_(3)^(−)and Cd^(2+).Our results demonstrated that the exposure to Cd^(2+)alone induced slight histopathological changes in the liver.However,malformations such as hepatic vacuolar degeneration and sinusoid dilatationwere exacerbated under co-exposure.Moreover,co-exposure induced the downregulation of antioxidants and the upregulation of the product malonaldehyde(MDA)from lipid peroxidation,indicating potent oxidative stress in the liver.The increased mRNA expression of IL-8,TNF-α,and IL-1β,along with the decreased expression level of TGF-β,indicated a synergistic inflammatory response in the organisms.Furthermore,the co-exposure led to an abnormal expression of P53,caspase-3,caspase-9,Bcl-2,and Bax,and disturbed the apoptosis in the liver through TUNEL staining analysis.Overall,our results imply that co-exposure synergistically affects inflammation,redox status,and apoptosis in flounders.Therefore,the findings from this study provide valuable perspectives on the ecological risk assessment of marine teleosts co-exposure to NO_(3)^(−)and Cd^(2+). 展开更多
关键词 Nitrate pollution Cadmium Japanese flounder Oxidative defense APOPTOSIS
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From defense chemistry to agroecological solutions:The evolving role of benzoxazinoids in plants
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作者 Tao Li Xueqin Liu +6 位作者 Sai Zhang Jialei Lei Ruiqi Li Peipei Ma Jianyu Wu Yufang Xu Huiyong Zhang 《The Crop Journal》 2025年第5期1333-1349,共17页
Benzoxazinoids(BXDs)are a class of plant secondary metabolites that play pivotal roles in plant defense against pathogens and pests,as well as in allelopathy.This review synthesizes recent advances in our understandin... Benzoxazinoids(BXDs)are a class of plant secondary metabolites that play pivotal roles in plant defense against pathogens and pests,as well as in allelopathy.This review synthesizes recent advances in our understanding of the structural and functional diversity of BXDs,the independent evolutionary trajectories of their biosynthetic pathways across different plant species,their metabolic transformations in target organisms,and the opportunities and challenges of optimizing BXD biosynthesis in crops through metabolic engineering.Compared with monocotyledons,dicotyledons employ a more diverse set of enzymes to catalyze the core reactions of BXD biosynthesis.This functional divergence—yet biochemical convergence—between monocotyledons and dicotyledons exemplifies the convergent evolution of BXD biosynthetic pathways in plants.BXDs act not only as potent antifeedants,insecticides,and antimicrobials but also function as signaling molecules that induce callose deposition and activate systemic immunity,thereby enhancing plant resistance to biotic stress.Furthermore,BXDs shape the rhizosphere by modulating microbial communities through species-specific antimicrobial activities and microbial detoxification mechanisms,ultimately exerting allelopathic effects that alter soil chemistry and nutrient dynamics.The translational potential of BXDs is increasingly recognized by synthetic biology approaches,including artificial intelligence-driven enzyme optimization,heterologous pathway engineering,and gene-editing to enhance crop resistance.Despite these promising prospects,challenges remain in balancing metabolic trade-offs and mitigating ecological risks associated with persistent accumulation of BXDs.Future research integrating multi-omics,evolutionary genomics,and microbiome studies will be essential to fully harness BXDs for sustainable crop improvement and reduced reliance on synthetic agrochemicals. 展开更多
关键词 Benzoxazinoids BIOSYNTHESIS Plant defense ALLELOPATHY Metabolic engineering
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Large Prey Growth in the Wolkowicz-Rothe-Shafer Predator-Prey System with Group Defense
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作者 André ZEGELING LIAO Jin 《数学理论与应用》 2025年第3期1-52,共52页
This paper investigates the number of limit cycles in a predator-prey system with group defense,intially introduced by Wolkowicz and later examined by Rothe and Shafer in the 1980’s.Under the assumption of large prey... This paper investigates the number of limit cycles in a predator-prey system with group defense,intially introduced by Wolkowicz and later examined by Rothe and Shafer in the 1980’s.Under the assumption of large prey growth,the system reduces to a perturbed singular system,whose limit cycles can be analyzed using geometric singular perturbation methods-primarily through the study of a slow-divergence integral.Our work completes partially the results previously obtained by Li and Zhu and by Hsu.We provide a comprehensive classification of all possible singular cycles capable of generating limit cycles and analyze the slow-divergence integral for the nine distinct types of cycle families that arise in a canard explosion.Based on these findings,we demonstrate that the maximum number of limit cycles emerging from the singular cycles is two in all cases,thereby confirming conjectures posed by Rothe-Shafer and Xiao-Ruan. 展开更多
关键词 Predator-prey system Group defense Singular perturbation Limit cycle
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Investigation into the degradation of 2,4,6-trichlorophenol utilizing a three-dimensional electrocatalytic reactor filled with fluorine-doped copper-carbon particle electrodes
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作者 Hongrui Zhang Wenyu Huang +4 位作者 Hainong Song Hanhui Yan Jia Zhang Fang Zhong Huilan Li 《Journal of Environmental Sciences》 2025年第9期701-719,共19页
The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated cata... The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated catalytic activity and minimal energy consumption continues to pose a significant challenge.In this research,Fluorine-doped copper-carbon(F/Cu-GAC)particle electrodes were effectively synthesized through an impregnationcalcination technique,utilizing granular activated carbon as the carrier and fluorinedoped modified copper oxides as the catalytic agents.The particle electrodes were subsequently utilized to promote the degradation of 2,4,6-trichlorophenol(2,4,6-TCP)in a threedimensional electrocatalytic reactor(3DER).The F/Cu-GAC particle electrodes were polarized under the action of electric field,which promoted the heterogeneous Fenton-like reaction in which H2O2 generated by two-electron oxygen reduction reaction(2e-ORR)of O_(2) was catalytically decomposed to·OH.The 3DER equipped with F/Cu-GAC particle electrodes showed 100%removal of 2,4,6-TCP and 79.24%removal of TOC with a specific energy consumption(EC)of approximately 0.019 kWh/g·COD after 2 h of operation.The F/Cu-GAC particle electrodes exhibited an overpotential of 0.38 V and an electrochemically active surface area(ECSA)of 715 cm^(2),as determined through linear sweep voltammetry(LSV)and cyclic voltammetry(CV)assessments.These findings suggest a high level of electrocatalytic performance.Furthermore,the catalytic mechanism of the 3DER equipped with F/Cu-GAC particle electrodes was elucidated through the application of X-ray photoelectron spectroscopy(XPS),electron spin resonance(ESR),and active species capture experiments.This investigation offers a novel approach for the effective degradation of 2,4,6-TCP. 展开更多
关键词 2 4 6-TRICHLOROPHENOL Heterogeneous Fenton-like process three-dimensional electrocatalytic reactor three-dimensional particle electrode system Fluorine-doped copper-carbon particle electrodes
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Changes in induced-antipredation defense traits and transcriptome regulation of rotifer Brachionus calyciflorus in response to nanoplastics
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作者 Huanhuan XU Xiaodan NAN +6 位作者 Yingying GE Yuxiang ZHOU Chunting ZHOU Kangning LIU Zhenzhen LI Man ZHANG Jiaxin YANG 《Journal of Oceanology and Limnology》 2025年第6期1877-1891,共15页
Nanoplastics(less than 1µm in size,NPs)have emerged as a significant pollutant in aquatic environment,posing considerable threats to freshwater biota.However,the mechanisms through which NPs modulate the predatio... Nanoplastics(less than 1µm in size,NPs)have emerged as a significant pollutant in aquatic environment,posing considerable threats to freshwater biota.However,the mechanisms through which NPs modulate the predation responses of these organisms remain poorly elucidated.We investigated the impacts of polystyrene NPs,characterized by a representative particle size(diameter:50 nm;concentration:0–8μg/L),on the anti-predation defense mechanisms of mature rotifer Brachionus calyciflorus against predator of rotifer Asplanchna brightwellii,utilizing transcriptomics to unravel the underlying molecular pathways.Results reveal that the posterolateral spine length and type of B.calyciflorus serve as robust indicators of defensive morphology,even in the presence of NPs exposure.Specifically,increasing concentrations of NPs and predator cues suppressed the defensive responses,which was associated with morphological transformations.This suppression was associated with the down-regulation of the HIF-1αsignaling pathway,implicating potentially its role in modulating fight-or-flight responses.Furthermore,we identified functional crosstalk among multiple signaling pathways,including HIF-1α,PI3K-Akt,FoxO,and mTOR,in B.calyciflorus,which may underpin the organism's responses to polystyrene NP exposure.These findings contribute to the advancement of predictive models to assess the ecological risks posed by polystyrene NPs contamination in aquatic ecosystems. 展开更多
关键词 ROTIFER Brachionus calyciflorus inducible defense Asplanchna kairomones nanoplastic TRANSCRIPTOME
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A Survey of Adversarial Examples in Computer Vision:Attack,Defense,and Beyond
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作者 XU Keyizhi LU Yajuan +1 位作者 WANG Zhongyuan LIANG Chao 《Wuhan University Journal of Natural Sciences》 2025年第1期1-20,共20页
Recent years have witnessed the ever-increasing performance of Deep Neural Networks(DNNs)in computer vision tasks.However,researchers have identified a potential vulnerability:carefully crafted adversarial examples ca... Recent years have witnessed the ever-increasing performance of Deep Neural Networks(DNNs)in computer vision tasks.However,researchers have identified a potential vulnerability:carefully crafted adversarial examples can easily mislead DNNs into incorrect behavior via the injection of imperceptible modification to the input data.In this survey,we focus on(1)adversarial attack algorithms to generate adversarial examples,(2)adversarial defense techniques to secure DNNs against adversarial examples,and(3)important problems in the realm of adversarial examples beyond attack and defense,including the theoretical explanations,trade-off issues and benign attacks in adversarial examples.Additionally,we draw a brief comparison between recently published surveys on adversarial examples,and identify the future directions for the research of adversarial examples,such as the generalization of methods and the understanding of transferability,that might be solutions to the open problems in this field. 展开更多
关键词 computer vision adversarial examples adversarial attack adversarial defense
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An Effective Adversarial Defense Framework:From Robust Feature Perspective
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作者 Baolin Li Tao Hu +2 位作者 Xinlei Liu Jichao Xie Peng Yi 《Computers, Materials & Continua》 2025年第10期2141-2155,共15页
Deep neural networks are known to be vulnerable to adversarial attacks.Unfortunately,the underlying mechanisms remain insufficiently understood,leading to empirical defenses that often fail against new attacks.In this... Deep neural networks are known to be vulnerable to adversarial attacks.Unfortunately,the underlying mechanisms remain insufficiently understood,leading to empirical defenses that often fail against new attacks.In this paper,we explain adversarial attacks from the perspective of robust features,and propose a novel Generative Adversarial Network(GAN)-based Robust Feature Disentanglement framework(GRFD)for adversarial defense.The core of GRFD is an adversarial disentanglement structure comprising a generator and a discriminator.For the generator,we introduce a novel Latent Variable Constrained Variational Auto-Encoder(LVCVAE),which enhances the typical beta-VAE with a constrained rectification module to enforce explicit clustering of latent variables.To supervise the disentanglement of robust features,we design a Robust Supervisory Model(RSM)as the discriminator,sharing architectural alignment with the target model.The key innovation of RSM is our proposed Feature Robustness Metric(FRM),which serves as part of the training loss and synthesizes the classification ability of features as well as their resistance to perturbations.Extensive experiments on three benchmark datasets demonstrate the superiority of GRFD:it achieves 93.69%adversarial accuracy on MNIST,77.21%on CIFAR10,and 58.91%on CIFAR100 with minimal degradation in clean accuracy.Codes are available at:(accessed on 23 July 2025). 展开更多
关键词 Adversarial defense robust features DISENTANGLEMENT VAE GAN
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λ-return-based aircraft maneuvering for terminal defense and positioning guidance strategies
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作者 DENG Shijie KOU Yingxin +2 位作者 LYU Maolong LI Zhanwu XU An 《Journal of Systems Engineering and Electronics》 2025年第6期1692-1708,共17页
Aiming at the terminal defense problem of aircraft,this paper proposes a method to simultaneously achieve terminal defense and seize the dominant position.The method employs aλ-return based reinforcement learning alg... Aiming at the terminal defense problem of aircraft,this paper proposes a method to simultaneously achieve terminal defense and seize the dominant position.The method employs aλ-return based reinforcement learning algorithm,which can be applied to the flight assistance decision-making system to improve the pilot’s survivability.First,we model the environment to simulate the interaction between air-to-air missiles and aircraft.Subsequently,we propose aλ-return based approach to improve the deep Q learning network(DQN),deep advantageous actor criticism(A2C),and proximity policy optimization(PPO)algorithms used to train manoeuvre strategies.The method employs an action space containing nine manoeuvres and defines the off-target distance at the end of the scene as a sparse reward for algorithm training.Simulation results show that the convergence speed of the three improved algorithms is significantly improved when using theλ-return method.Moreover,the effect of the fetch value on the convergence speed is verified by ablation experiments.In order to solve the illegal behavior problem in the training process,we also design a backtracking-based illegal behavior masking mechanism,which improves the data generation efficiency of the environment model and promotes effective algorithm training. 展开更多
关键词 λ-return terminal defense positioning guidance reinforcement learning
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Finding the balance: Modifying the cholesterol and steroidal glycoalkaloid synthesis pathway in tomato(Solanum lycopersicum L.) for human health, fruit flavor, and plant defense
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作者 Vincenzo Averello IV Adrian D.Hegeman Changbin Chen 《Horticultural Plant Journal》 2025年第1期42-56,共15页
Unlike most plants, members of the genus Solanum produce cholesterol and use this as a precursor for steroidal glycoalkaloids. The production of the compounds begins as a branch from brassinosteroid biosynthesis, whic... Unlike most plants, members of the genus Solanum produce cholesterol and use this as a precursor for steroidal glycoalkaloids. The production of the compounds begins as a branch from brassinosteroid biosynthesis, which produces cholesterol that is further modified to produce steroidal glycoalkaloids. During the cholesterol biosynthesis pathway, genetic engineering could alter the formation of cholesterol from provitamin D3(7-dehydrocholesterol) and produce vitamin D3. Cholesterol is a precursor for many steroidal glycoalkaloids, including a-tomatine and esculeoside A. Alpha-tomatine is consumed by mammals and it can reduce cholesterol content and improve LDL:HDL ratio. When there is a high a-tomatine content, the fruit will have a bitter flavor, which together with other steroidal glycoalkaloids serving as protective and defensive compounds for tomato against insect, fungal, and bacterial pests. These compounds also affect the rhizosphere bacteria by recruiting beneficial bacteria. One of the steroidal glycoalkaloids, esculeoside A increases while fruit ripening. This review focuses on recent studies that uncovered key reactions of the production of cholesterol and steroidal glycoalkaloids in tomato connecting to human health, fruit flavor, and plant defense and the potential application for tomato crop improvement. 展开更多
关键词 CHOLESTEROL Steroidal glycoalkaloids TOMATO Biosynthesis a-tomatine STEROLS TERPENOIDS Plant defense
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A Review of Three-Dimensional Research on Urban Recreation Space Based on CiteSpace
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作者 LIU Yongli 《Journal of Landscape Research》 2025年第1期30-34,共5页
In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring t... In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring the scientific development trend and research hotspots in this field.The results show that the number of published documents shows a fluctuating upward trend,and the significant growth rate reflects the role of policy orientation in promoting the concept of compact city.The co-occurrence analysis of keywords reveals the research hotspots of“compact city”,“recreation space”and“urban park”,while the emergence of new keywords such as“vertical city”and“spatial justice”indicates the new trend of recent research.The cluster analysis and timeline map further show the evolution of research themes,with“compact city”being the largest cluster and having rich connections with other themes such as“urban design”and“urban park”. 展开更多
关键词 Compact city Urban recreation space three-dimensional CITESPACE
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Resection of a ganglioneuroma encasing major blood vessels using three-dimensional laparoscopy combined with organ suspension:A case report
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作者 Guo-Zhen Wu Shen-Zhe Fang +1 位作者 Shi-An Yu Min Yu 《World Journal of Gastrointestinal Surgery》 2025年第8期467-475,共9页
BACKGROUND Ganglioneuroma is a rare,well-differentiated,slow-growing benign tumor of the peripheral nerves,with surgical resection being the only curative treatment.Surgical resection of ganglioneuromas encasing major... BACKGROUND Ganglioneuroma is a rare,well-differentiated,slow-growing benign tumor of the peripheral nerves,with surgical resection being the only curative treatment.Surgical resection of ganglioneuromas encasing major blood vessels remains a substantial clinical challenge.Traditionally,these cases often require open abdominal surgery or combined organ resections,and in some instances,the tumors are considered unresectable.Currently,no reports have described the resection of such tumors via laparoscopy.CASE SUMMARY A 35-year-old woman was admitted to our hospital after the incidental discovery of a retroperitoneal space-occupying lesion.Imaging revealed a mass with the celiac axis and superior mesenteric artery passing through it.A neurogenic tumor was suspected,with ganglioneuroma being the most likely diagnosis.Following comprehensive preoperative preparation,the retroperitoneal tumor was resected using a three-dimensional laparoscopy combined with an organ suspension technique.The surgical approach involved incising the tumor along the vascular axis and conducting meticulous,vascular-preserving tumor excision.The operation lasted approximately 458 minutes,with an estimated blood loss of 50 mL.The patient was discharged on the 8th postoperative day.A transient liver injury occurred after surgery but improved rapidly.After 11 months of postoperative follow-up,no complications or tumor recurrence were observed.CONCLUSION This case illustrates the feasibility of minimally invasive laparoscopic resection for retroperitoneal ganglioneuromas encasing major blood vessels. 展开更多
关键词 Ganglioneuromas Retroperitoneal three-dimensional laparoscopy Organ suspension Case report
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Reconfigurable Three-Dimensional Thermal Dome
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作者 Yuhong Zhou Fubao Yang +5 位作者 Liujun Xu Pengfei Zhuang Dong Wang Xiaoping Ouyang Ying Li Jiping Huang 《Engineering》 2025年第3期236-244,共9页
Thermal metamaterial represents a groundbreaking approach to control heat conduction,and,as a crucial component,thermal invisibility is of utmost importance for heat management.Despite the flourishing development of t... Thermal metamaterial represents a groundbreaking approach to control heat conduction,and,as a crucial component,thermal invisibility is of utmost importance for heat management.Despite the flourishing development of thermal invisibility schemes,they still face two limitations in practical applications.First,objects are typically completely enclosed in traditional cloaks,making them difficult to use and unsuitable for objects with heat sources.Second,although some theoretical proposals have been put forth to change the thermal conductivity of materials to achieve dynamic invisibility,their designs are complex and rigid,making them unsuitable for large-scale use in real threedimensional(3D)spaces.Here,we propose a concept of a thermal dome to achieve 3D invisibility.Our scheme includes an open functional area,greatly enhancing its usability and applicability.It features a reconfigurable structure,constructed with simple isotropic natural materials,making it suitable for dynamic requirements.The performance of our reconfigurable thermal dome has been confirmed through simulations and experiments,consistent with the theory.The introduction of this concept can greatly advance the development of thermal invisibility technology from theory to engineering and provide inspiration for other physical domains,such as direct current electric fields and magnetic fields. 展开更多
关键词 Thermal domes Reconfigurable metamaterials three-dimensional invisibility
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