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Chinese Journal of Polymer Science 2024年第5期42卷 675-682,I0004,I0010页

作者： Jiang-Tao Sun zhi-Yong Fan Yi-wei Mao wei Li wei Zhu Dao-Sheng Cai Qing-Song wei State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430074China National Engineering Research Centre for High Efficiency Grinding Hunan UniversityChangsha410082China Wuhan EasyMFG Technology CO. LTDWuhan430074China

High speed sintering,a new powder-bed fusion additive manufacturing technology,utilizes infrared lights(IR)to intensely heat and melt polymer *** presence of defects such as porosity,which is associated with particle coalescence,is highly dependdent on the level of energy *** study investigate the influcence of energy input on porosity and its subsequent effects on the mechanical properties and microstructures of PEBA *** parts were manufactured with a variety of lamp powers,resulting in a range of energy input levels spanning from low to ***,they underwent testing using Archimedes’method,followed by tensile *** porosity,mechanical characteristics,and energy input exhibit a strong correlation;inadequate energy input was the primary cause of pore *** the reduced IR light power resulted in the following outcomes:porosity,ultimate tensile strength,and elongation of 1.37%,7.6 MPa,and 194.2%,*** the energy input was further increased,the porosity was reduced to as low as 0.05%and the ultimate tensile strength and elongation were increased to their peak values of 233.8%and 9.1 MPa,respectively.

关键词： High speed sintering Additive manufacturing Energy input Powder bed fusion PEBA

High-Order Two-Scale Asymptotic Paradigm for the Elastodynamic Homogenization of Periodic Composites

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Acta Mechanica Solida Sinica 2024年第1期37卷 124-138页

作者： wei-zhi Luo Mu He Liang Xia Qi-Chang He State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China Laboratoire Modélisation et Simulation Multi-Echelle MSME UMR 8208 CNRSUniversite Gustave Eiffel77454 Marne-la-ValléeFrance

The classical two-scale asymptotic paradigm provides macroscopic and microscopic analyses for the elastodynamic homogenization of periodic composites based on the spatial or/and temporal variable,which offers an approximate framework for the asymptotic homogenization analysis of the motion ***,in this framework,the growing complexity of the homogenization formulation gradually becomes an obstacle as the asymptotic order *** such a context,a compact,fast,and accurate asymptotic paradigm is *** work reviews the high-order spatial two-scale asymptotic paradigm with the effective displacement field representation and optimizes the implementation by symmetrizing the tensor to be ***,the modified implementation gets rid of the excessive memory consumption required for computing the high-order tensor,which is demonstrated by representative one-and two-dimensional *** numerical results show that(1)the contrast of the material parameters between media in composites directly affects the convergence rate of the asymptotic results for the homogenization of periodic composites,(2)the convergence error of the asymptotic results mainly comes from the truncation error of the modified asymptotic homogenized motion equation,and(3)the excessive norm of the normalized wavenumber vector in the two-dimensional inclusion case may lead to a non-convergence of the asymptotic results.

关键词： Composites Homogenization Asymptotic analysis Dynamics Dispersion

Perception field based imitation learning for unlabeled multi-agent pathfinding

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

作者： Wenjie CHU Ailun YU wei ZHANG Haiyan ZHAO zhi JIN School of Computer Science Peking University Key Laboratory of High-Confidence Software Technologies (Peking University) Ministry of Education

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

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

Predictive model using four ferroptosis-related genes accurately predicts gastric cancer prognosis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2018-2037页

作者： Li Wang wei-hua Gong Department of Emergency The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310000Zhejiang ProvinceChina Department of Surgery The Second Affiliated Hospital Zhejiang University School of MedicineHangzhou 310052Zhejiang ProvinceChina

BACKGROUND Gastric cancer(GC)is a common malignancy of the digestive *** to global 2018 cancer data,GC has the fifth-highest incidence and the thirdhighest fatality rate among malignant *** than 60%of GC are linked to infection with Helicobacter pylori(***),a gram-negative,active,microaerophilic,and helical *** parasite induces GC by producing toxic factors,such as cytotoxin-related gene A,vacuolar cytotoxin A,and outer membrane ***,or iron-dependent programmed cell death,has been linked to GC,although there has been little research on the link between *** infection-related GC and *** To identify coregulated differentially expressed genes among ferroptosis-related genes(FRGs)in GC patients and develop a ferroptosis-related prognostic model with discrimination *** Gene expression profiles of GC patients and those with ***-associated GC were obtained from The Cancer Genome Atlas and Gene Expression Omnibus(GEO)*** FRGs were acquired from the FerrDb database.A ferroptosis-related gene prognostic index(FRGPI)was created using least absolute shrinkage and selection operator–Cox *** predictive ability of the FRGPI was validated in the GEO ***,we verified the expression of the hub genes and the activity of the ferroptosis inducer FIN56 in GC cell lines and *** Four hub genes were identified(NOX4,MTCH1,GABARAPL2,and SLC2A3)and shown to accurately predict GC and ***-associated *** FRGPI based on the hub genes could independently predict GC patient survival;GC patients in the high-risk group had considerably worse overall survival than did those in the low-risk *** FRGPI was a significant predictor of GC prognosis and was strongly correlated with disease ***,the gene expression levels of common immune checkpoint proteins dramatically increased in the highrisk subgroup of the FRGPI *** hub genes were also conf

关键词： Ferroptosis Gastric cancer Helicobacter pylori infection Immune checkpoint protein Prognostic model Ferroptosis-related gene prognostic index

A Low Cost, Green Sustainable and Biodegradable Biomass-based Fluorine-free Water and Oil Repellent

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Chinese Journal of Polymer Science 2024年第4期42卷 480-491页

作者： zhi-wei Shen Shu-Feng Hu Chen Zeng wei-Qing Kong Mei-Fang Zhu State Key Laboratory for Modification of Chemical Fibers&Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China State Key Laboratory of Pulp and Paper Engineering School of Light Industry and EngineeringSouth China University of TechnologyGuangzhou510630China

With the global ban on plastics intensifying, the substitution of plastic with paper has garnered increasing attention. However, the inadequate water and oil repellency of pulp molding hinders its practical applications. Currently, the common method to enhance the oil and water repellency of pulp molding is by adding fluorinated water and oil repellents. Nevertheless, fluorinated compounds are environmentally and physiologically harmful. Therefore, the development of fluorine-free, water and oil repellent alternatives is crucial. In this study, chitosan and stearic acid were utilized as the first and second layers of the oil and water repellent coatings, respectively. The coated samples exhibited favorable water repellency, with a water contact angle of 116.4°, and excellent oil repellency, achieving a 12/12 rating on the kit scale. Importantly, the samples did not exhibit any leakage after being soaked in hot water and hot oil at 95±5℃ for 30 min, demonstrating remarkable performance as a barrier against hot water and oil. Moreover, the coated samples displayed outstanding mechanical properties, thermal stability, biodegradability, and recyclability. The approach presented in this study is simple, cost-effective, environmentally friendly, and represents a promising technique for producing fluoride-free, oil-and water-resistant pulp molding products.

关键词： Biomass Fluoride-free Oil-andwater-resistant Plasticfree

Gastrointestinal contrast-enhanced ultrasonography for diagnosis and treatment of peptic ulcer in children

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World Journal of Gastroenterology 2024年第7期30卷 705-713页

作者： Yu-hua Zhang zhi-hua Xu Shuang-Shuang Ni Hong-Xia Luo Department of Ultrasound The Second Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

BACKGROUND The detection rate of peptic ulcer in children is improving,with development of diagnostic *** is the gold standard for the diagnosis of peptic ulcer,but it is an invasive *** contrast-enhanced ultrasonography(CEUS)has the advantages of being painless,noninvasive,nonradioactive,easy to use,and *** To investigate the clinical value of CEUS for diagnosis and treatment of peptic ulcer in *** We investigated 43 children with digestive tract symptoms in our hospital from January 2021 to June *** children were examined by routine ultrasound,gastrointestinal CEUS,and *** pathological results of gastroscopy were taken as the gold *** ultrasonography was performed before gastrointestinal *** ultrasound showed the thickness of the gastroduodenal wall,gastric peristalsis,and the adjacent organs and tissues around the abdominal *** CEUS recorded the thickness of the gastroduodenal wall;the size,location and shape of the ulcer;gastric peristalsis;and adjacent organs and tissues around the abdominal *** results of routine ultrasound and gastrointestinal ultrasound were compared with those of gastroscopy to evaluate the diagnostic results and coincidence rate of routine ultrasound and gastrointestinal *** children received informed consent from their guardians for *** study was reviewed and approved by the hospital medical ethics *** Among the 43 children,17(15 male,2 female)were diagnosed with peptic ulcer by *** were 26 children with nonpeptic *** were eight cases of peptic ulcer and 35 of nonpeptic ulcer diagnosed by conventional *** diagnostic coincidence rate of peptic ulcer in children diagnosed by conventional ultrasound was 79.1%(34/43),which was significantly different from that of gastroscopy(P=0.033).It indicates that the coincidence rate of gastrointestinal contrast-enhanc

关键词： Contrast-enhanced ultrasound Peptic ulcer Children Gastrointestinal tract Abdominal pain Acoustic contrast agent

Research progress on micro-force measurement of a hydrate particle system

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Petroleum Science 2024年第4期21卷 2169-2183页

作者： Qiang Luo wei Li zhi-Hui Liu Feng Wang zhi-Chao Liu Fu-Long Ning Faculty of Engineering China University of Geosciences (Wuhan) Suzhou Laboratory

It remains a great challenge to understand the hydrates involved in phenomena in practical oil and gas systems. The adhesion forces between hydrate particles, between hydrate particles and pipe walls, and between hydrate particles and reservoir particles are essential factors that control the behaviors of clathrate hydrates in different applications. In this review, we summarize the typical micro-force measurement apparatus and methods utilized to study hydrate particle systems. In addition, the adhesion test results, the related understandings, and the applied numerical calculation models are systematically discussed.

关键词： Clathrate hydrates Hydrate particle Micro-force measurements Adhesion Interactions

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基于阻塞先验知识的文本层次分类模型

模式识别与人工智能 2010年第4期23卷 456-463页

作者：李文苗夺谦卫志华王炜立同济大学计算机科学与技术系上海201804 南昌大学信息工程学院南昌330031

文本层次分类中阻塞现象是影响层次分类器性能的重要原因.针对这一问题,提出基于阻塞先验知识的文本层次分类模型.该模型包括两部分:首先对阻塞分布进行估计,提出"阻塞对"识别技术,重点在于获取严重的阻塞方向;其次,把分析出的阻塞先验... 详细信息

文本层次分类中阻塞现象是影响层次分类器性能的重要原因.针对这一问题,提出基于阻塞先验知识的文本层次分类模型.该模型包括两部分:首先对阻塞分布进行估计,提出"阻塞对"识别技术,重点在于获取严重的阻塞方向;其次,把分析出的阻塞先验知识融合到分类过程中,利用层次拓扑结构修正算法,引导阻塞文本"回归"正确分类路径.在中文语料TanCorp上的实验表明,该算法在没有额外增加分类器数目的前提下,能有效改善层次分类性能,是解决层次分类阻塞问题的一种方法.另外,与平面分类算法比较后,该算法更稳定.

关键词：阻塞文本分类层次结构先验知识动态修正

Salinity effect-induced ENSO amplitude modulation in association with the interdecadal Pacific Oscillation

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Journal of Oceanology and Limnology 2024年第4期42卷 1019-1036页

作者： Hai zhi Xiaokun WANG Rong-hua ZHANG Pengfei LIN Jifeng QI College of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Laoshan Laboratory Qingdao 266237China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China Key Laboratory of Ocean Circulation and Waves Institute of Oceanologyand Center for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China

A 110-year ensemble simulation of an ocean general circulation model(OGCM)was analyzed to identify the modulation of salinity interdecadal variability on El Niño-Southern Oscillation(ENSO)amplitude in the tropical Pacific during *** simulating results show that sea surface salinity(SSS)variation in the region exhibits notable and coherent interdecadal variability signal,which is closely associated with the Interdecadal Pacific Oscillation(IPO).As salinity increases or reduces,the SSS modulations on ENSO amplitude during its warm/cold events vary asymmetrically with positive/negative IPO ***,salinity interdecadal variability can enhance or reduce ENSO-related conditions in upper-ocean stratification,contributing noticeably to ENSO *** anomalies associated with the mixed layer depth and barrier layer thickness can modulate ENSO amplitude during positive and negative IPO phases,resulting in the asymmetry of sea surface temperature(SST)anomaly in the tropical *** positive IPO phases,SSS interdecadal variability contributes positively to El Niño amplitude but negatively to La Niña amplitude by enhancing or reducing SSS interannual variability,and vice versa during negative IPO ***,the results indicate that the modulation of the ENSO amplitude by the SSS interdecadal variability is 15%-28%during negative IPO phases and 30%-20%during positive IPO phases,***,the SSS interdecadal variability associated with IPO and its modulation on ENSO amplitude in the tropical Pacific are among factors essentially contributing ENSO diversity.

关键词： El Niño-Southern Oscillation(ENSO)amplitude Interdecadal Pacific Oscillation(IPO) ocean salinity variability tropical Pacific upper-ocean stratification

Electroacupuncture activates AMPKa1 to improve learning and memory in the APP/PS1 mouse model of early Alzheimer's disease by regulating hippocampal mitochondrial dynamics

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Journal of Integrative Medicine 2024年第5期22卷 588-599页

作者： wei-wei Jia hua-wei Lin Min-guang Yang Ya-ling Dai Yan-yi Ding Wen-shan Xu Si-nuo Wang Ya-jun Cao Sheng-xiang Liang zhi-fu Wang Cong Chen wei-lin Liu College of Rehabilitation Medicine Fujian University of Traditional Chinese Medicine The Institute of Rehabilitation Industry Fujian University of Traditional Chinese Medicine National-Local Joint Engineering Research Center of Rehabilitation Medicine Technology Fujian University of Traditional Chinese Medicine Traditional Chinese Medicine Rehabilitation Research Center of State Administration of Traditional Chinese Medicine Fujian University of Traditional Chinese Medicine

Objective: Studies have shown that electroacupuncture(EA) can alleviate cognitive impairments from Alzheimer's disease(AD) by regulating the expression of adenosine monophosphate-activated protein kinase(AMPK), but the specific mechanism involved remains to be elucidated. Therefore, this study explores the potential mechanism by which EA improves cognitive function from the perspective of mitochondrial ***: The four-month-old transgenic mice with amyloid precursor protein(APP)/presenilin 1(PS1)and AMPKa1-subunit conditional knockout(AMPKa1-cKO) were used for experiments. To evaluate the effects of EA treatment on cognitive function, the T-maze and Morris water maze were used. In addition,chemical exchange saturation transfer, thioflavin staining, transmission electron microscopy, mitochondrial membrane potential, and Western blotting were used to examine the potential mechanisms underlying the effects of EA on APP/PS1 ***: Both APP/PS1 mice and AMPKa1-cKO mice exhibited dysfunction in mitochondrial dynamics accompanied by learning and memory impairment. Inactivation of the AMPK/peroxisome proliferatoractivated receptor-γ coactivator-1a(PGC-1a) pathway increased pathological amyloid-β(Aβ) deposition and aggravated the dysfunction in mitochondrial dynamics. In addition, EA rescued learning and memory deficits in APP/PS1 mice by activating the AMPK/PGC-1a pathway, specifically by reducing pathological Aβ deposition, normalizing energy metabolism, protecting the structure and function of mitochondria,increasing the levels of mitochondrial fusion proteins, and downregulating the expression of fission proteins. However, the therapeutic effect of EA on cognition in APP/PS1 mice was hindered by ***: The regulation of hippocampal mitochondrial dynamics and reduction in Aβ deposition via the AMPK/PGC-1a pathway are critical for the ability of EA to ameliorate cognitive impairment in APP/PS1 mice.

关键词： Adenosine monophosphate-activated protein kinase Alzheimer’s disease Cognitive impairment Electroacupuncture Hippocampus Mitochondrial dynamics