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Challenges and opportunities in Quaternary palynology

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Science China Earth Sciences 2024年第7期67卷 2148-2161页

作者： Qinghai XU Houyuan LU Zhuo zheng College of Geographical Sciences Hebei Key Laboratory of Environmental Change and Ecological ConstructionHebei Normal UniversityShijiazhuang 050024China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Earth Sciences and Engineering Sun Yat-sen UniversityZhuhai 519082China

Quaternary palynology plays a pivotal role in investigating global climate change and various other research fields,serving as an essential tool for the quantitative analysis of paleoenvironment changes.However,due to the vast diversity of terrestrial ecosystems and intricate interactions between vegetation,climate,and human activities,further advancements are required in the following aspects within this discipline.(1)The accuracy of classification in pollen morphology and fossil pollen identification needs improvement,particularly at the species level.This represents a significant challenge in present Quaternary palynology.Computer-aided intelligent recognition holds promise as a solution for species identification based on more detail pollen morphology.(2)Most pollen-based vegetation and climate reconstructions overlook the significance of bare ground.Neglecting bare ground can lead to substantial inaccuracies when quantitatively reconstructing past vegetation and climate.(3)While pollen records provide reliable information on paleoclimate changes,current quantitative climate reconstruction models heavily rely on modern pollen datasets derived from present-day vegetation disturbed more or less by human activities.This introduces bias and uncertainties into paleoclimate reconstruction.(4)Although pollen can serve as an indicator of human activities,accurately quantifying the intensity of human influence remains challenging.Improving accurate identification of crop pollen,reconstructing reliable land cover/use data,and integrating multidisciplinary data may enhance the identification and quantification of signals related to human activity in pollen records.

关键词： Quaternary palynology Paleoclimate Paleovegetation Human activity

Adaptive Trajectory Tracking Control for Nonholonomic Wheeled Mobile Robots:A Barrier Function Sliding Mode Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1007-1021页

作者： Yunjun zheng Jinchuan zheng Ke Shao Han Zhao Hao Xie Hai Wang the School of Mechanical Engineering Hefei University of TechnologyHefei 230009China the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyHawthorn VIC 3122Australia the School of Civil Aviation Northwestern Polytechnical UniversityXi’an 710072China the Shanghai Aerospace Control Technology Institute Shanghai 201109 the School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China the College of Science HealthEngineering and EducationMurdoch UniversityPerth WA6150Australia

The trajectory tracking control performance of nonholonomic wheeled mobile robots(NWMRs)is subject to nonholonomic constraints,system uncertainties,and external disturbances.This paper proposes a barrier function-based adaptive sliding mode control(BFASMC)method to provide high-precision,fast-response performance and robustness for NWMRs.Compared with the conventional adaptive sliding mode control,the proposed control strategy can guarantee that the sliding mode variables converge to a predefined neighborhood of origin with a predefined reaching time independent of the prior knowledge of the uncertainties and disturbances bounds.Another advantage of the proposed algorithm is that the control gains can be adaptively adjusted to follow the disturbances amplitudes thanks to the barrier function.The benefit is that the overestimation of control gain can be eliminated,resulting in chattering reduction.Moreover,a modified barrier function-like control gain is employed to prevent the input saturation problem due to the physical limit of the actuator.The stability analysis and comparative experiments demonstrate that the proposed BFASMC can ensure the prespecified convergence performance of the NWMR system output variables and strong robustness against uncertainties/disturbances.

关键词： Adaptive sliding mode barrier function nonholonomic wheeled mobile robot(NWMR) trajectory tracking control

Spatiotemporal Changes of Snow Depth in Western Jilin,China from 1987 to 2018

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Chinese Geographical Science 2024年第2期34卷 357-368页

作者： WEI Yanlin LI Xiaofeng GU Lingjia zheng Zhaojun zheng Xingming JIANG Tao Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China Changchun Jingyuetan Remote Sensing Experiment Site Chinese Academy of SciencesChangchun 130102China College of Electronic Science and Engineering Jilin UniversityChangchun 130012 National Meteorological Satellite Meteorological Center Beijing 100081China

Seasonal snow cover is a key global climate and hydrological system component drawing considerable attention due to glob-al warming conditions.However,the spatiotemporal snow cover patterns are challenging in western Jilin,China due to natural condi-tions and sparse observation.Hence,this study investigated the spatiotemporal patterns of snow cover using fine-resolution passive mi-crowave(PMW)snow depth(SD)data from 1987 to 2018,and revealed the potential influence of climate factors on SD variations.The results indicated that the interannual range of SD was between 2.90 cm and 9.60 cm during the snowy winter seasons and the annual mean SD showed a slightly increasing trend(P>0.05)at a rate of 0.009 cm/yr.In snowmelt periods,the snow cover contributed to an increase in volumetric soil water,and the change in SD was significantly affected by air temperature.The correlation between SD and air temperature was negative,while the correlation between SD and precipitation was positive during December and March.In March,the correlation coefficient exceeded 0.5 in Zhenlai,Da’an,Qianan,and Qianguo counties.However,the SD and precipitation were neg-atively correlated over western Jilin in October,and several subregions presented a negative correlation between SD and precipitation in November and April.

关键词： snow cover snow depth(SD) climate changes passive microwave(PMW) western Jilin,China

最优影响因素下超燃冲压发动机煤油流动水平管冷却

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机械设计与研究 2024年第2期40卷 29-31,39页

作者：芮雪郑少梅孙文福长治职业技术学院机械电子工程系山西长治046000 青岛理工大学机械与汽车工程学院山东青岛266109 三亚学院理工学院海南三亚572022

水和煤油在管道中的温度分布是不均匀的,且超燃冲压发动机煤油流动水平管冷却过程,没有针对不同区域换热过程进行进一步细分,导致煤油流动水平管冷却通道内速度场的分布规律不够精准,最优冷却因素分析结果失真,影响煤油的冷却效果。为... 详细信息

水和煤油在管道中的温度分布是不均匀的,且超燃冲压发动机煤油流动水平管冷却过程,没有针对不同区域换热过程进行进一步细分,导致煤油流动水平管冷却通道内速度场的分布规律不够精准,最优冷却因素分析结果失真,影响煤油的冷却效果。为解决这一问题,提出一种超燃冲压发动机煤油流动水平管最优冷却因素分析。通过构建航空煤油的对流换热控制模型,将整个换热过程分成不同的阶段,获取进口温度、压力、热流密度对传热的影响,计算出加热壁面内、壁面与流体三者间的传热系数,得出的流动水平管冷却的边界条件,并以此为依据获取对水平管内超临界航空煤油传热的影响因素,完成对超燃冲压发动机煤油流动水平管优化冷却。实验结果证明:所提方法的管壁温度拟合度与实际值基本一致,且冷却效果好,表明所提方法在超燃冲压发动机煤油流动水平管冷却方面具有一定的应用价值。

关键词：超燃冲压发动机煤油流动水平管冷却仿真方法局部高温分布规律

Current status and challenges of pig-to-human organ xenotransplantation

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Science China(Life Sciences) 2024年第4期67卷 829-831页

作者： Minghui Fang Yong-Guang Yang zheng Hu Key Laboratory of Organ Regeneration&Transplantation of Ministry of Education and National-Local Joint Engineering Laboratory of Animal Models for Human DiseasesThe First Hospital of Jilin UniversityChangchun 130061China

Organ shortage is a global issue.Data collected by the Global Observatory on Donation and Transplantation reveals that over 150,000 solid organ transplants are conducted globally each year,a 52%increase from 2010(http... 详细信息

关键词： globally global shortage

The Multiple Roles of Autophagy in Neural Function and Diseases

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Neuroscience Bulletin 2024年第3期40卷 363-382页

作者： Yan-Yan Li zheng-Hong Qin Rui Sheng Department of Pharmacology and Laboratory of Aging and Nervous Diseases Jiangsu Key laboratory of Neuropsychiatric DiseasesCollege of Pharmaceutical Sciences of Soochow UniversitySuzhou 215123China

Autophagy involves the sequestration and delivery of cytoplasmic materials to lysosomes,where proteins,lipids,and organelles are degraded and recycled.According to the way the cytoplasmic components are engulfed,autophagy can be divided into macroautophagy,microautophagy,and chaperone-mediated autophagy.Recently,many studies have found that autophagy plays an important role in neurological diseases,including Alzheimer's disease,Parkinson's disease,Huntington's disease,neuronal excitotoxicity,and cerebral ischemia.Autophagy maintains cell homeostasis in the nervous system via degradation of misfolded proteins,elimination of damaged organelles,and regulation of apoptosis and inflammation.AMPK-mTOR,Beclin 1,TP53,endoplasmic reticulum stress,and other signal pathways are involved in the regulation of autophagy and can be used as potential therapeutic targets for neurological diseases.Here,we discuss the role,functions,and signal pathways of autophagy in neurological diseases,which will shed light on the pathogenic mechanisms of neurological diseases and suggest novel targets for therapies.

关键词： Autophagy Neurodegenerative diseases Cerebral ischemia AMPK mTOR Beclin 1 TP53 Endoplasmic reticulum stress

Advances of biomarkers in nasopharyngeal carcinoma’s early detection

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Science Bulletin 2024年第2期69卷 141-145页

作者： Xiao-Hui zheng Allan Hildesheim Wei-Hua Jia State Key Laboratory of Oncology in South China Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510060China Costa Rican Agency for Biomedical Investigation INCIENSA FoundationSan Jose 10108Costa Rica

Nasopharyngeal carcinoma(NPC),a highly invasive and metastatic cancer,is widely prevalent in South China,Southeast Asia,and North Africa.NPC patients with stages I and II are often asymptomatic.Therefore,NPC patients are usually diagnosed with advanced-stage(stages III and IV)at their first visit.Detection of NPC at early stage is the key to improve the survival of patients.Epstein-Barr virus(EBV)plays an essential role in NPC occurrence in endemic areas.EBV-based biomarkers,including EBV antibody in serum and EBV DNA in plasma,have been specifically proposed for NPC early detection.Herein,we summarize recent advances in biomarkers for the early detection of NPC.

关键词： patients nasopharyngeal Nasopharyngeal

The neuroscience of pain,addiction,and anesthesia

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Zoological Research 2024年第3期45卷 709-710页

作者： Ji Hu Ping zheng School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China State Key Laboratory of Medical Neurobiology Institutes of Brain ScienceMOE Frontier Center for Brain ScienceDepartment of Neurology of Zhongshan HospitalFudan UniversityShanghai 200032China

Researchers and clinicians have long been interested in the mechanisms of pain,anesthesia,and addiction.The International Association for the Study of Pain(IASP)defines pain as an unpleasant sensory and emotional experience associated with,or resembling that associated with,actual or potential tissue damage(Raja et al.,2020).Drug addiction refers to a condition of reliance that develops from regular drug consumption,which may lead to withdrawal symptoms when use is halted.Anesthesia involves the complete loss of consciousness induced by an inhaled or intravenous anesthetic(Tosello et al.,2022).In this special collection,Zoological Research presents research findings focused on pain,addiction,and anesthesia.

关键词： anesthesia damage

Analysis and monitoring of drug therapy in a patient with peptic ulcer complicated by infection:A case report

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World Journal of Clinical Cases 2024年第8期12卷 1530-1535页

作者： Yan-Ping Gou Yue Huang Li Chen Wei zheng Yun-Hua zheng The Second People’s Hospital of Meishan City&Renshou County People’s Hospital Meishan 620500Sichuan ProvinceChina Quality Evaluation and Medical Record Management The Affiliated Hospital of Southwest Jiaotong University&The Third People's Hospital of ChengduChengdu 610000Sichuan ProvinceChina Patriotic Health Campaign Qionglai City Health BureauChengdu 610000Sichuan ProvinceChina

BACKGROUND The role of primary-level medical pharmacists in medical institutions in China is limited;therefore,it is necessary to explore the role of pharmacists in the process of drug treatment.CASE SUMMARY A Chinese pharmacist participated in the complete treatment of a patient with a duodenal ulcer.The rationale for drug treatment was evaluated,and adjustments were made to the antacid and anti-infective regimen,as well as the dose and frequency of administration.Body temperature,routine blood examination,and adverse drug reactions were strictly monitored.During treatment,the pharmacist recommended anti-infective therapy with ampicillin-sulbactam,which effectively controlled the infection.Additionally,the pharmacist suggested changing famotidine to lansoprazole for acid suppression and gastroprotective treatment,combined with Chinese patent medicine such as Kangfuxin Liquid.This is the first case report of a pharmacist in primary-level medical institutions adjusting drug use for patients with duodenal ulcer and pulmonary infection.CONCLUSION A pharmacist participated in the treatment process,provided individualized medication adjustment,and achieved good clinical results.

关键词： Ampicillin-sulbactam Famotidine Lansoprazole Kangfuxin Liquid Chinese pharmacist Case report