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Path-Following Control With Obstacle Avoidance of Autonomous Surface Vehicles Subject to Actuator Faults

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 956-964页

作者： li-Ying Hao Gege Dong Tieshan li Zhouhua peng the School of Marine Electrical Engineering Dalian Maritime UniversityDalian 116026China the School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731the Navigation CollegeDalian Maritime UniversityDalian 116026 the Yangtze Delta Region Institute(Huzhou) Huzhou 313001China

This paper investigates the path-following control problem with obstacle avoidance of autonomous surface vehicles in the presence of actuator faults,uncertainty and external *** surface vehicles inevitably suffer from actuator faults in complex sea environments,which may cause existing obstacle avoidance strategies to *** reduce the influence of actuator faults,an improved artificial potential function is constructed by introducing the lower bound of actuator efficiency *** nonlinear state observer,which only depends on measurable position information of the autonomous surface vehicle,is used to address uncertainties and external *** using a backstepping technique and adaptive mechanism,a path-following control strategy with obstacle avoidance and fault tolerance is designed which can ensure that the tracking errors converge to a small neighborhood of *** with existing results,the proposed control strategy has the capability of obstacle avoidance and fault tolerance ***,the comparison results through simulations are given to verify the effectiveness of the proposed method.

关键词： Actuator faults autonomous surface vehicle(ASVs) improved artificial potential function nonlinear state observer obstacle avoidance

Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

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Science China Chemistry 2024年第8期67卷 2524-2546页

作者： jun-Bing lin Dong-Sheng Ji peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 2010 to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1,3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： organocatalysis asymmetric catalysis ammonium dienolate cascade reaction difunctionalization

Effect of temperature on suspension magnetization roasting of hematite using biomass waste as reductant:A perspective of gas evolution

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Journal of Central South University 2024年第6期31卷 1870-1887页

作者： CAO Yue SUN Yong-sheng HAN Yue-xin GAO peng li Yan-jun School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang 110819China

The magnetization reduction of hematite using biomass waste can effectively utilize waste and reduce CO_(2) emission to achieve the goals of carbon peaking and carbon *** effects of temperatures on suspension magnetization roasting of hematite using biomass waste for evolved gases have been investigated using TG-FTIR,Py-GC/MS and gas composition *** mixture reduction process is divided into four *** the temperature range of 200-450℃ for mixture,the release of CO_(2),acids,and ketones is dominated in gases *** yield and concentration of small molecules reducing gases increase when the temperature increases from 450 to 900℃.At 700℃,the volume concentrations of CO,H_(2) and CH_(4) peak at 8.91%,8.90% and 4.91%,*** the suspension magnetization roasting process,an optimal iron concentrate with an iron grade of 70.86%,a recovery of 98.66% and a magnetic conversion of 45.70% is obtained at 700℃.Therefore,the magnetization reduction could react greatly in the temperature range of 600 to 700℃ owing to the suitable reducing *** study shows a detail gaseous evolution of roasting temperature and provides a new insight for studying the reduction process of hematite using biomass waste.

关键词： suspension magnetization roasting biomass pyrolysis gases evolution reduction behavior

Synthesis and Antibacterial Activities of Selenide Derivatives of Benzisoselenazolone

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Wuhan University Journal of Natural Sciences 2001年第4期6卷 851-853页

作者： Yang li ping, Wu jun, peng Yun shan, liu Xiu fang, Xu Han sheng College of Chemistry and Molecular, Wuhan University, Wuhan 430072, China College of Chemistry and Molecular Wuhan University Wuhan China

A series of Benzisolselenazolone (BISA) derivatives were synthesized and evaluated for their antibacterial activities againstE coli. by using LKB-2277 bioactivity monitor. Other bioactivities were tested by the method of High Throughput Screening for pharmaceutical activity compounds (HTP) BISA derivatives 3b, at the concentration of 40 μg/mL, showed 100%antibacterial activity and 62%inhibition rate of aldose reductase (at the concentration of 5μg/mL). These new compound structures have determined by IR,1H NMR and MS spectra.

关键词： BISA Ebselen antibacterial activity NO synthase Aldose reductase

Climate-growth relationships of Pinus tabuliformis along an altitudinal gradient on Baiyunshan Mountain,Central China

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Journal of Forestry Research 2024年第1期35卷 202-212页

作者： Xiaoxu Wei Jianfeng peng Jinbao li Jinkuan li Meng peng Xuan li Yameng liu Jiaxin li College of Geography and Environmental Science Henan UniversityKaifeng 475004People’s Republic of China Key Laboratory of Earth System Observation and Simulation of He’nan Province Kaifeng 475004People’s Republic of China Department of Geography University of Hong KongPokfulamHong Kong SARPeople’s Republic of China HKU Shenzhen Institute of Research and Innovation Shenzhen 518057People’s Republic of China

A set of standard chronologies for tree-ring width(TRW),earlywood width(EWW)and latewood width(LWW)in Pinus tabuliformis *** an altitudi-nal gradient(1450,1400,and 1350 m a.s.l.)on Baiyunshan Mountain,Central China to analyze the effect of varying temperature and precipitation on growth along the *** analyses showed that at all three altitudes and the TRW and EWW chronologies generally had signifi-cant negative correlations with mean and maximum tem-peratures in the current April and May and with minimum temperatures in the prior July and August,but significant positive correlations with precipitation in the current *** were generally significantly negative between LWW chronologies and all temperatures in the prior July and August,indicating that the prior summer temperature had a strong lag effect on the growth of *** that increased with *** correlation with the standard-ized precipitation evapotranspiration index(SPEI)confirmed that wet conditions in the current May promoted growth of TR and EW at all *** altitudinal differences were also found;at 1400 m,there were significant positive correlations between EWW chronologies and SPEI in the current April and significant negative correlations between LWW chronologies and SPEI in the current September,but these correlations were not significant at 1450 *** 1350 m,there were also significant negative correlations between the TRW and the EWW chronologies and SPEI in the prior October and the current July and between LWW chronology and SPEI in the current August,but these cor-relations were not significant at 1400 *** correlation results showed a stable response of EWW in relation to the SPEI in the current May at all three altitudes and of LWW to maximum temperature in the prior July-August at 1400 m from 2002 to *** EWW chronology at 1400 m and the LWW chronology at 1450 m were identified as more suitable for climate reconstruction.T

关键词： Tree rings Climate response Altitudinal gradient Baiyunshan Mountain Pinus tabuliformis Carr

Role of deubiquitinase JOSD2 in the pathogenesis of esophageal squamous cell carcinoma

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World Journal of Gastroenterology 2024年第6期30卷 565-578页

作者： Wen-peng Wang Dan Shi Duo Yun jun Hu Jie-Fu Wang Jia liu Yan-peng Yang Ming-Rui li jun-FengWang Da-Lu Kong Department of Colorectal Oncology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin’s Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin 300060China Department of Gastrointestinal Surgery Tianjin Nan Kai HospitalTianjin Medical UniversityTianjin Key Laboratory of Acute Abdomen Disease Associated Organ Injury and ITCWM RepairInstitute of Integrative Medicine for Acute Abdominal DiseasesTianjin 300100China Department of Oncology The First Hospital of HohhotHohhot 010000Inner Mongolia Autonomous RegionChina Department of Endocrinology Dazhou Central HospitalDazhou 635000Sichuan ProvinceChina

BACKGROUND Esophageal squamous cell carcinoma(ESCC)is a deadly malignancy with limited treatment ***(DUBs)have been confirmed to play a crucial role in the development of malignant ***2 is a DUB involved in con-trolling protein deubiquitination and influencing critical cellular processes in *** To investigate the impact of JOSD2 on the progression of *** Bioinformatic analyses were employed to explore the expression,prognosis,and enriched pathways associated with JOSD2 in *** transduction was utilized to manipulate JOSD2 expression in ESCC cell lines(KYSE30 and RESULTS )Preliminary research indicated that JOSD2 was highly expressed in ESCC tissues,which was associated with poor *** analysis demonstrated that JOSD2 was upregulated in ESCC cell lines compared to normal esophageal ***2 knockdown inhibited ESCC cell activity,including proliferation and colony-forming ***,JOSD2 knockdown decreased the drug resistance and migration of ESCC cells,while JOSD2 overexpression enhanced these *** vivo xenograft assays further confirmed that JOSD2 promoted tumor proliferation and drug resistance in ***,JOSD2 appears to activate the MAPK/ERK and PI3K/AKT signaling *** spectrometry was used to identify crucial substrate proteins that interact with JOSD2,which identified the four primary proteins that bind to JOSD2,namely USP47,IGKV2D-29,HSP90AB1,and *** JOSD2 plays a crucial role in enhancing the proliferation,migration,and drug resistance of ESCC,suggesting that JOSD2 is a potential therapeutic target in ESCC.

关键词： Esophageal squamous cell carcinoma JOSD2 Ubiquitination Biomarker Targeted therapy Drug resistance

Unsupervised construction of health indicator for rotating machinery via multi-criterion feature selection and attentive variational autoencoder

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Science China(Technological Sciences) 2024年第5期67卷 1524-1537页

作者： li XinYu CHENG ChangMing peng ZhiKe State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai200240China School of Mechanical Engineering Ningxia UniversityYinchuan750021China

Health indicator(HI)construction is a crucial task in degradation evaluation and facilitates the prognostic and health management(PHM)of rotating *** interference from artificial labeling,the HI construction approaches in an unsupervised manner have attracted substantial ***,current unsupervised methods generally struggle with two problems:(1)ignorance of both redundancy between features and global variability of features during the feature selection process;(2)inadequate utilization of information from different sampling *** tackle these problems,this work develops a novel unsupervised approach for HI construction that integrates multi-criterion feature selection and the Attentive Variational Autoencoder(Attentive VAE).Explicitly,a multi-criterion feature selection(Mc FS)algorithm together with an elaborately designed metric is proposed to determine a superior feature subset,considering the relevance,the redundancy,and the global variability of features ***,for the adequate utilization of the information from distinct sampling moments,a deep learning model named Attentive VAE is *** Attentive VAE is solely fed with the selected features in the health state for model training and the HI is derived through the reconstruction error to reveal the degradation degree of *** case studies based on genuine experimental datasets are involved to quantitatively evaluate the superiority of the developed approach,demonstrating its superiority over other unsupervised methods for characterizing degradation *** effectiveness of both the Mc FS algorithm and the Attentive VAE is verified by ablation experiments,respectively.

关键词： health indicator(HI) unsupervised learning multi-criterion feature selection global variability attention mechanism

Growth hormone promotes the reconstruction of injured axons in the hypothalamo-neurohypophyseal system

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Neural Regeneration Research 2024年第10期19卷 2249-2258页

作者： Kai li Zhanpeng Feng Zhiwei Xiong jun Pan Mingfeng Zhou Weizhao li Yichao Ou Guangsen Wu Mengjie Che Haodong Gong junjie peng Xingqin Wang Songtao Qi junxiang peng Department of Neurosurgery Institute of Brain DiseasesNanfang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

Previous studies have shown that growth hormone can regulate hypothalamic energy metabolism, stress, and hormone release. Therefore, growth hormone has great potential for treating hypothalamic injury. In this study, we established a specific hypothalamic axon injury model by inducing hypothalamic pituitary stalk electric lesions in male mice. We then treated mice by intraperitoneal administration of growth hormone. Our results showed that growth hormone increased the expression of insulin-like growth factor 1 and its receptors, and promoted the survival of hypothalamic neurons, axonal regeneration, and vascular reconstruction from the median eminence through the posterior pituitary. Altogether, this alleviated hypothalamic injury-caused central diabetes insipidus and anxiety. These results suggest that growth hormone can promote axonal reconstruction after hypothalamic injury by regulating the growth hormone-insulin-like growth factor 1 axis.

关键词： arginine vasopressin growth hormone hypothalamo-neurohypophyseal system hypothalamus injury insulin-like growth factor 1 oxytocin regeneration

Recent advances of high-entropy electrocatalysts for water electrolysis by electrodeposition technology:a short review

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Rare Metals 2024年第6期43卷 2371-2390页

作者： Han-Ming Zhang Shao-Fei Zhang li-Hao Zuo Jia-Kang li jun-Xia Guo peng Wang Jin-Feng Sun Lei Dai Hebei Key Laboratory of Flexible Functional Materials School of Materials Science and EngineeringHebei University of Science and TechnologyShijiazhuang 050018China Department of Chemistry National University of SingaporeSingapore117543Singapore

Hydrogen is considered as the promising energy carrier to substitute traditional fossil fuel,due to its cleanliness,renewability and high energy *** electrolysis is a simple and eonvenient technology for hydrogen *** efficiency of water electrolysis for hydrogen production is limited by the electrocatalytic performances on hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).The exorbitant Pt-and Ir-/Ru-based electrocatalysts as optimal HER and OER electrocatalysts,respectively,restrict water electrolysis ***,non-precious metal-based high-entropy electrocatalysts have exhibited excellent electrocatalytic activities and long-term stabilities for water electrolysis,as promising precious cataly st ***,the construction of the high-entropy electroc atalysts is vital to water electrolysis *** technology is an efficient method for the preparation of high-entropy electrocatalysts due to its simple,fast,energy-saving and environmental-friendly ***-component co-precipitation facilely occurs during the electroredox in electrodeposition ***-entropy alloys,oxides,(oxy)hydroxides,phosphides and phosphorus sulfide oxides have been successfully prepared by galvanostatic,potentiostatic electrodeposition,cyclic voltammetry,pulse,nanodroplet-mediated and cathodic plasma electrodeposition ***,introduction of the development of high-entropy electrocatalysts synthesized by electrodeposition technology is significant to researchers and *** and outlooks are also concluded to boost the industrial application of electrodeposition in water electrolysis and other energy conversion areas.

关键词： High-entropy electrocatalysts Electrodeposition technology Water electrolysis Multi-component co-precipitation Excellent electrocatalytic performances