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Isobaric enzymatic assays reveal depth-dependent variation in microbial ectoenzyme activities in the deepest ocean on Earth

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Science China Earth Sciences 2025年第1期68卷 185-194页

作者： Junwei CAO Jiahua WANG Hongge ZHANG Junhao DENG Binbin PAN Jiawang chen li ZHANG Jiasong FANG College of Oceanography and Ecological Science Shanghai Ocean University Ocean College Zhejiang University Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and Technology

Microbial ectoenzymes play essential roles in the transformation and mineralization of organic matter in the ***, conventional methods for measuring microbial ectoenzyme activities(MEAs) in the deep ocean under atmospheric conditions can misrepresent the metabolic activities of indigenous microbial communities. To overcome this limitation, we measured the activities of three microbial ectoenzymes(aminopeptidase, α-glucosidase, and β-glucosidase) under both atmospheric and in situ pressure conditions in seawater collected using pressure-retaining and non-pressure-retaining samplers in the Challenger Deep, Mariana Trench. In the case of aminopeptidase and α-glucosidase, the highest isobaric MEAs were observed in the surface layer(50 m), followed by those at abyssopelagic depths(4,000–6,000 m) for aminopeptidase, hadal realm(10,903 m)for α-glucosidase, while β-glucosidase activity exhibited the highest value at 10,903 m. Furthermore, the isobaric MEAs in hadal waters were commonly found to be higher than the decompressed counterparts, highlighting the importance of pressure-retaining sampling and isobaric enzymatic assays. The half-saturation constant(Km) showed a general decreasing trend with depth,suggesting that the deep ocean microbes might have adapted to the high-pressure and oligotrophic environment by increasing their ectoenzyme's affinity to substrate. Furthermore, particle-free MEAs contribute more to the total MEAs in the deep ocean than particle-associated MEAs, suggesting the significance of cell-associated and dissolved ectoenzymes in ocean *** study provides a foundation for future investigations of MEAs in the ocean and has important implications for understanding the dynamics of microbially mediated biogeochemical cycling in marine ecosystems.

关键词： Pressure-retaining sampling Microbial ectoenzyme activity Deep-sea microbes High pressure Mariana Trench

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Mutual regulation of microglia and astrocytes after Gas6 inhibits spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 557-573页

作者： Jiewen chen Xiaolin Zeng Le Wang Wenwu Zhang Gang li Xing cheng Peiqiang Su Yong Wan Xiang li Department of Spine Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Guangdong Province Key Laboratory of Orthopedics and Traumatology GuangzhouGuangdong ProvinceChina

Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord *** and astrocytes play key roles in the spinal cord injury micro-environment and share a close ***,the mechanisms involved remain *** this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming *** expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord *** vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between *** further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling ***,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling *** vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function ***,Gas6 may play a role in the treatment of spinal cord *** can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.

关键词： astrocytes Axl cell polarization Gas6 Hippo signal inflammatory micro-environment intercellular interaction microglia single-cell sequencing spinal cord injury

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Poly(lactic acid)/Poly(butylene adipate-co-terephthalate)films with simultaneous high oxygen barrier and fast degradation properties

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Green Energy & Environment 2025年第1期10卷 1-10页

作者： Mengjing Yang Yuxi Mao Penghui Zhang Jie li Zeming Tong Zhenguo liu Yanhui chen Institute of Flexible Electronics Northwestern Polytechnical UniversityXi'an710072China Key Laboratory of Flexible Electronics of Zhejiang Province Ningbo Institute of Northwestern Polytechnical University218 Qingyi RoadNingbo315103China School of Chemistry and Chemical Engineering Shaanxi Key Laboratory of Macromolecular Science and TechnologyKey Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi'an 710072China

Although poly(lactic acid)(PLA)is a good environmentally-friendly bio-degradable polymer which is used to substitute traditional petrochemical-based polymer packaging films,the barrier properties of PLA films are still insufficient for high-barrier packaging *** this study,oxygen scavenger hydroxyl-terminated polybutadiene(HTPB)and cobalt salt catalyst were incorporated into the PLA/poly(butylene adipate-co-terephthalate)(PLA/PBAT),followed by melting extrusion and three-layer co-extrusion blown film process to prepare the composite *** oxygen permeability coefficient of the composite film combined with 6 wt%oxygen scavenger and 0.4 wt%catalyst was decreased significantly from 377.00 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1) to 0.98 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1),showing a remarkable enhancement of 384.69 times compared with the PLA/PBAT composite ***,the degradation behavior of the composite film was also accelerated,exhibiting a mass loss of nearly 60%of the original mass after seven days of degradation in an alkaline environment,whereas PLA/PBAT composite film only showed a mass loss of 32%.This work has successfully prepared PLA/PBAT composite films with simultaneously improved oxygen barrier property and degradation behavior,which has great potential for high-demanding green chemistry packaging industries,including food,agricultural,and military packaging.

关键词： Barrier property Oxygen scavenging Blow molding Eco-packaging Degradable composite film

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弹载电动舵机幂次滑模反演控制

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北京理工大学学报 2016年第10期36卷 1037-1042页

作者：吕帅帅林辉陈晓雷李兵强西北工业大学自动化学院陕西西安710129

针对高频响弹载电动舵机系统存在的齿隙非线性、参数时变、未知扰动等问题,提出一种幂次型快速Terminal滑模反演控制策略.设计连续可微函数逼近齿隙非线性环节的死区模型,建立拟合系统的状态空间模型并划分为3个子系统进行控制设计.采... 详细信息

针对高频响弹载电动舵机系统存在的齿隙非线性、参数时变、未知扰动等问题,提出一种幂次型快速Terminal滑模反演控制策略.设计连续可微函数逼近齿隙非线性环节的死区模型,建立拟合系统的状态空间模型并划分为3个子系统进行控制设计.采用反演控制思想设计快速幂次Terminal滑模控制器,内环采用直接转矩控制控制策略,提高响应速度.应用Lyapunov方法证明闭环系统跟踪误差的有限时间收敛特性,实现了对齿隙非线性的精确补偿.实验结果验证了所提出控制策略的有效性,与反演控制和PID控制策略相比,弹载电动舵机的控制精度、收敛速度及鲁棒性有显著提高.

关键词：高频响弹载舵机永磁同步电机快速幂次终端滑模控制反演控制齿隙非线性

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MixerKT:A Knowledge Tracing Model Based on Pure MLP Architecture

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Computers, Materials & Continua 2025年第1期82卷 485-498页

作者： Jun Wang Mingjie Wang Zijie li Ken chen Jiatian Mei Shu Zhang Key Laboratory of Education Informatization for Nationalities Ministry of EducationYunnan Normal UniversityKunming650000China Yunnan Key Laboratory of Smart Education Yunnan Normal UniversityKunming650000China

In the field of intelligent education,the integration of artificial intelligence,especially deep learning technologies,has garnered significant *** tracing(KT)plays a pivotal role in this field by predicting students’future performance through the analysis of historical interaction data,thereby assisting educators in evaluating knowledgemastery and tailoring instructional *** knowledge tracingmethods,largely based on Recurrent Neural Networks(RNNs)and Transformer models,primarily focus on capturing long-term interaction patterns in sequential ***,these models may neglect crucial short-term dynamics and other relevant *** paper introduces a novel approach to knowledge tracing by leveraging a pure Multilayer Perceptron(MLP)*** proposeMixerKT,a knowledge tracing model based on theHyperMixer framework,which uniquely integrates global and localMixer feature *** architecture enables more effective extraction of both long-terminteraction trends and recent learning behaviors,addressing limitations in currentmodels thatmay overlook these key *** evaluations on twowidely-used datasets,ASSIS Tments2009 and Algebra2005,demonstrate that MixerKT consistently outperforms several state-of-the-art models,including DKT,SAKT,and Separated Self-Attentive Neural Knowledge Tracing(SAINT).Specifically,MixerKT achieves higher prediction accuracy,highlighting its effectiveness in capturing the nuances of learners’knowledge *** results indicate that our model provides a more comprehensive representation of student learning patterns,enhancing the ability to predict future performance with greater precision.

关键词： Knowledge tracing multilayer perceptron channel mixer sequence mixer

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Vector meson's spin alignments in high energy reactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-Hui chen Zuo-Tang liang Yu-Gang Ma Xin-li Sheng Qun Wang Key Laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of Mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National Laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation

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Synthesis,Structure and Catalytic Properties of Three Copper Complexes

Synthesis,Structure and Catalytic Properties of Three Copper...

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中国化学会第六届全国结构化学学术会议

作者： Wen-Qian chen,lei li,Tao lei,Yan-Mei chen,Wei liu,Ya-Hong li~* Key Laboratory of Organic Synthesis of Jiangsu Province,College of Chemistry,Chemical Engineering and materials Science,Soochow University.Suzhou 215123,People’s Republic of China,

The Henry reaction is one of the powerful reactions in constructing C-C bonds in organic *** has been found that Cuand Cu complexes are the active catalysts for the Henry *** new polynuclear Cuand Cu complexes support...

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GA-Diff:一种快速XML文档变化检测算法

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计算机工程与应用 2004年第18期40卷 186-188,207页

作者：陈振洲李磊中山大学软件研究所广州510275

XML文档的变化检测可以广泛应用于构建XML数据仓库中的数据存储、文档模式提取以及增量查询等方面。随着被检测的数据规模的增加,对检测算法的效率也提出了更高的要求。利用遗传算法(GA),论文提出了一种新的XML文档的变化检测方法GA-Di... 详细信息

XML文档的变化检测可以广泛应用于构建XML数据仓库中的数据存储、文档模式提取以及增量查询等方面。随着被检测的数据规模的增加,对检测算法的效率也提出了更高的要求。利用遗传算法(GA),论文提出了一种新的XML文档的变化检测方法GA-Diff,针对XML文档树给出了树编辑距离的定义、实现算法并验证了该算法的效率。

关键词：变化检测遗传算法编辑脚本动态规划

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一种板式贮箱在轨加注过程流体分布的数值模拟

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空间控制技术与应用 2016年第5期42卷 53-56,62页

作者：陈磊李永刘锦涛李文唐飞北京控制工程研究所北京100190

在轨加注的主要任务是实现推进剂的在轨管理与传输,其中推进剂的在轨管理是通过板式贮箱实现的.空间环境下板式贮箱内液体定位和重复补加技术是在轨加注的关键技术,决定了在轨加注任务的成败.为了确保板式贮箱对流体的在轨管理性能,需... 详细信息

在轨加注的主要任务是实现推进剂的在轨管理与传输,其中推进剂的在轨管理是通过板式贮箱实现的.空间环境下板式贮箱内液体定位和重复补加技术是在轨加注的关键技术,决定了在轨加注任务的成败.为了确保板式贮箱对流体的在轨管理性能,需要开展大量的仿真与试验研究.以在轨加注技术中叶片式板式贮箱进行研究,采用VOF(volume of fluid)两相流动模型对微重力条件下板式贮箱内流体行为以及加注过程中推进剂的流动特性进行数值仿真,获得流体分布规律,验证板式贮箱良好的管理特性,为板式贮箱设计与在轨加注技术研究提供参考.

关键词：微重力叶片式贮箱流体行为在轨加注

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Bi_2Se_3薄膜及Pb掺杂电子结构变化的第一性原理（英文）

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稀有金属材料与工程 2016年第11期45卷 2809-2813页

作者：陈磊朱亚波李延龄范贺良赫占军中国矿业大学徐州江苏221116 江苏师范大学徐州江苏221008

利用第一性原理平面波赝势方法,研究Bi_2Se_3从块体到薄膜的电子结构变化特性。通过分析材料的原子位置以及电子间相互作用,具体探讨块体、双层和单层薄膜及单层Pb掺杂薄膜的能带结构、态密度等。计算结果表明,这几种材料的价带和导带... 详细信息

利用第一性原理平面波赝势方法,研究Bi_2Se_3从块体到薄膜的电子结构变化特性。通过分析材料的原子位置以及电子间相互作用,具体探讨块体、双层和单层薄膜及单层Pb掺杂薄膜的能带结构、态密度等。计算结果表明,这几种材料的价带和导带主要由原子的p态构成,同时由于Bi(Pb)的6s轨道态对价带顶的影响,它们的带隙类型随着材料结构的变化,发生从直接带隙到间接带隙的转变,此外Pb掺杂单层薄膜后产生的Se(1’)层对其电子结构的变化有重要影响。

关键词： Bi2Se3薄膜能带态密度电子结构

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