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Drought shifts soil nematode trophic groups and mediates the heterotrophic respiration

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Journal of Plant Ecology 2024年第2期17卷 100-109页

作者： Cancan zhao Yuanhu Shao Huijie Lu Aimée T.Classen Zuyan Wang ying li Yanchun liu Zhongling Yang Guoyong li Shenglei Fu International Joint Research Laboratory for Global Change Ecology School of Life SciencesHenan UniversityKaifeng 475004China Henan Dabieshan National Field Observation and Research Station of Forest Ecosystem Zhengzhou 450046China Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions Ministry of EducationCollege of Environment and PlanningHenan UniversityKaifeng 475004China Henan Key Laboratory of Integrated Air Pollution Control and Ecological Security Kaifeng 475004China Department of Ecology and Evolutionary Biology University of MichiganAnn ArborMI 48109USA South China Botanical Garden Chinese Academy of SciencesGuangzhou 510650China Department of Natural Resource of Henan Province Institute of Natural Resources Survey and PlanningZhengzhou 450000China

As the most diverse metazoan taxa,soil nematodes serve a diversity of functions in soil food webs and thus can regulate microbial community composition and affect organic matter decomposition and nutrient turnover *** nematodes depend on water flms to access food resources,drought can negatively affect nematode-microbial food webs,yet the impacts of drought on nematode diversity and abundance and how these changes may infuence food web members and their functions are hardly ***,we coupled research along a drought gradient in arid and semiarid grasslands with a detailed intact plant-soil microcosm experiment to explore the patterns and mechanisms of how drought impacts nematode abundance and carbon footprint,microbial phospholipid fatty acid(PLFA)and heterotrophic soil ***,in the feld and the microcosm experiments,we found that nematode abundance,carbon footprint and diversity,microbial PLFA and heterotrophic respiration were reduced under drier *** addition,drought altered nematode and microbial community composition,through reducing the nematode channel ratio and increasing the relative fungivorous nematode abundance and the fungal to bacterial *** soil decomposition channel shifted from a bacterial to a fungal pathway in response to drought,indicating decelerated heterotrophic respiration under *** results highlight the important contribution of soil nematodes and their associated microbial food web to soil carbon *** fndings underscore the need to incorporate key soil fauna into terrestrial ecosystem model evaluation.

关键词： soil biota fungal energy channel bacterial energy channel carbon footprint arid grassland

Plume-lithosphere interaction in the Comei Large Igneous Province: Evidence from two types of mafic dykes in Gyangze, south Tibet, China

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China Geology 2024年第1期7卷 80-90页

作者： Ya-ying Wang ling-sen Zeng li-e Gao li-long Yan ling-hao zhao Jia-hao Gao ying-long Di Guang-xu li Yi-hong Tian Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China China Nonferrous Metals(Guilin)Geology and Mining Co. LtdGuilin 541004China

Two suites of mafic dykes,T1193-A and T1194-A,outcrop in Gyangze area,southeast *** are in the area of Comei liP and have indistinguishable field occurrences with two other dykes in Gyangze,T0902 dyke with 137.7±1.3 Ma zircon age and T0907 dyke with 142±1.4 Ma zircon age reported by Wang YY et al.(2016),indicating coeval formation *** all the four diabase dykes into consideration,two different types,OIB-type and weak enriched-type,can be ***“OIB-type”samples,including T1193-A and T0907 dykes,show OIB-like geochemical features and have initial Sr-Nd isotopic values similar with most mafic products in Comei Large Igneous Provinces(liP),suggesting that they represent melts directly generated from the Kerguelen mantle ***“weak enriched-type”samples,including T1194-A and T0902 dykes,have REEs and trace element patterns showing withinplate affinity but have obvious Nb-Ta-Ti negative *** show uniform lowerεNd(t)values(−6‒−2)and higher 87Sr/86Sr(t)values(0.706‒0.709)independent of their MgO variation,indicating one enriched mantle *** their closely spatial and temporal relationship with the widespread Comei liP magmatic products in Tethyan Himalaya,these“weak enriched-type”samples are consistent with mixing of melts from mantle plume and the above ancient Tethyan Himalaya subcontinental lithospheric mantle(SCLM)in different *** weak enriched mafic rocks in Comei liP form one special rock group and most likely suggest large scale hot mantle plume-continental lithosphere *** process may lead to strong modification of the Tethyan Himalaya lithosphere in the Early Cretaceous.

关键词： OIB type diabase Comei Large Igneous Province Weakly enriched diabase Plume-lithosphere interaction Nb-Ta-Ti negative anomaly Kerguelen plume Geological survey engineering Tibet Plateau

EPR-Net: constructing a non-equilibrium potential landscape via a variational force projection formulation

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National Science Review 2024年第7期11卷 135-147页

作者： Yue zhao Wei Zhang Tiejun li Center for Data Science Peking University Zuse Institute Berlin Department of Mathematics and Computer Science Freie Universit?t Berlin Laboratory of Mathematics and Applied Mathematics(LMAM)and School of Mathematical Sciences Peking University Center for Machine Learning Research Peking University

We present EPR-Net, a novel and effective deep learning approach that tackles a crucial challenge in biophysics: constructing potential landscapes for high-dimensional non-equilibrium steady-state ***-Net leverages a nice mathematical fact that the desired negative potential gradient is simply the orthogonal projection of the driving force of the underlying dynamics in a weighted inner-product ***, our loss function has an intimate connection with the steady entropy production rate(EPR),enabling simultaneous landscape construction and EPR estimation. We introduce an enhanced learning strategy for systems with small noise, and extend our framework to include dimensionality reduction and the state-dependent diffusion coefficient case in a unified fashion. Comparative evaluations on benchmark problems demonstrate the superior accuracy, effectiveness and robustness of EPR-Net compared to existing methods. We apply our approach to challenging biophysical problems, such as an eight-dimensional(8D)limit cycle and a 52D multi-stability problem, which provide accurate solutions and interesting insights on constructed landscapes. With its versatility and power, EPR-Net offers a promising solution for diverse landscape construction problems in biophysics.

关键词： high-dimensional potential landscape non-equilibrium system entropy production rate dimensionality reduction deep learning

Quantum self-attention neural networks for text classification

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Science China(Information Sciences) 2024年第4期67卷 301-313页

作者： Guangxi li Xuanqiang zhao Xin WANG Institute for Quantum Computing Baidu Research Centre for Quantum Software and Information University of Technology Sydney QICI Quantum Information and Computation Initiative Department of Computer ScienceThe University of Hong Kong Thrust of Artificial Intelligence Information HubHong Kong University of Science and Technology(Guangzhou)

An emerging direction of quantum computing is to establish meaningful quantum applications in various fields of artificial intelligence, including natural language processing(NLP). Although some efforts based on syntactic analysis have opened the door to research in quantum NLP(QNLP), limitations such as heavy syntactic preprocessing and syntax-dependent network architecture make them impracticable on larger and real-world data sets. In this paper, we propose a new simple network architecture, called the quantum selfattention neural network(QSANN), which can compensate for these limitations. Specifically, we introduce the self-attention mechanism into quantum neural networks and then utilize a Gaussian projected quantum self-attention serving as a sensible quantum version of self-attention. As a result, QSANN is effective and scalable on larger data sets and has the desirable property of being implementable on near-term quantum devices. In particular, our QSANN outperforms the best existing QNLP model based on syntactic analysis as well as a simple classical self-attention neural network in numerical experiments of text classification tasks on public data sets. We further show that our method exhibits robustness to low-level quantum noises and showcases resilience to quantum neural network architectures.

关键词： quantum neural networks self-attention natural language processing text classification parameterized quantum circuits

Adaptive Consensus of Uncertain Multi-Agent Systems With Unified Prescribed Performance

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1310-1312页

作者： Kun li Kai zhao Yongduan Song The authors are with the School of Automation Chongqing UniversityChongqing 400044China

Dear Editor,An adaptive consensus control algorithm for uncertain multi-agent systems(MAS),capable of guaranteeing unified prescribed performance,is presented in this *** many existing prescribed performance related works,the developed control exhibits some ***,a distributed prescribed time observer is introduced so that not only each follower is able to estimate the leader’s signal within a predetermined time,but also the control design for each agent is independent with its neighbors.

关键词： agent prescribed Uncertain

Numerical investigation of the coupled aero-hydrodynamic performances of a semi-submersible floating offshore wind turbine with inclined columns

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Journal of Hydrodynamics 2024年第2期36卷 316-330页

作者： ying-jie Xue Xiao-long Yang Wei-wen zhao De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Offshore Oil Engineering Co.Ltd. Tianjin300461China

Numerical investigations of floating platforms with different outer column inclined angles under two operating conditions of regular wave and irregular wave are presented in this paper.A coupled aero-hydrodynamic computational fluid dynamics in-house solver FOWT-UALM-SJTU is applied for the ***,the validation for wave and wind generation are conducted to determine mesh distribution *** on these,the hydrodynamic motion response,aerodynamic performance and wake flow are analyzed to explore the impact of inclined *** spectral analysis on the motion response under wave action,discuss the aerodynamic attack angle and inflow wind velocity along the blade spanwise direction in detail,reveal different trends in wake development and *** results show that for the regular wave condition with the increase of inclined angles,the equilibrium position of surge motion is constantly rising,while pitch is *** maximum root mean square(rms)value occurs at angle=30°,compared with the original OC4 FOWT,the rms in power and thrust increase 0.35%,0.71%.And there are two low regions of attack angle and high regions of axial inflow velocity,corresponding to aerodynamic *** spectral analysis indicates that the natural frequency of pitch motion will increase with inclined ***,from the middle to far region of wake flow,the velocity recovery of FOWT with inclined angle will become faster,which is beneficial for downstream turbines to enhance more wind energy.

关键词： Floating offshore wind turbine numerical simulation aero-hydrodynamic coupled analysis floating platform with inclinedcolumns wake flow recovery

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高超声速飞行器上升段最优制导间接法研究

宇航学报 2011年第2期32卷 297-302页

作者：李惠峰李昭莹北京航空航天大学宇航学院北京100191

高超声速飞行器的机身-推进一体化设计使得气动和推进之间存在强非线性耦合,本文针对高超声速飞行器的特点,提出了求解最优上升轨迹的一种可行方案。在零侧滑角和力矩瞬间平衡假设下对上升段飞行问题进行最优建模,将质量引入为状态量,... 详细信息

高超声速飞行器的机身-推进一体化设计使得气动和推进之间存在强非线性耦合,本文针对高超声速飞行器的特点,提出了求解最优上升轨迹的一种可行方案。在零侧滑角和力矩瞬间平衡假设下对上升段飞行问题进行最优建模,将质量引入为状态量,以最省燃料为指标,以推力方向为最优控制量,根据极大值原理推导一阶最优条件。为数值求解两点边值问题,以解析解作为初始猜想,应用经典的有限差分方法和改进的牛顿法,在满足攻角过程约束下,通过同伦算法迭代求解最优轨迹。仿真在给定的初始约束和终端约束下进行,结果表明该制导算法能够实现对高超声速飞行器上升轨迹的优化,以参考面积为同伦参数的迭代方法,能够保证算法的收敛性和快速性。

关键词：高超声速飞行器最优控制两点边值问题上升段制导轨迹优化

Optimization of inter-seasonal nitrogen allocation increases yield and resource-use efficiency in a water-limited wheat-maize cropping system in the North China Plain

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The Crop Journal 2024年第3期12卷 907-914页

作者： Xiaonan Zhou Chenghang Du Haoran li Zhencai Sun Yifei Chen Zhiqiang Gao Zhigan zhao yinghua Zhang Zhimin Wang ying liu College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193China College of Information and Electrical Engineering China Agricultural UniversityBeijing 100193China Ministerial and Provincial Co-Innovation Centre for Endemic Crops Production with High-Quality and Efficiency in Loess Plateau Taigu 030801ShanxiChina

Winter wheat–summer maize cropping system in the North China Plain often experiences droughtinduced yield reduction in the wheat season and rainwater and nitrogen(N)fertilizer losses in the maize *** study aimed to identify an optimal interseasonal water-and N-management strategy to alleviate these *** ratios of allocation of 360 kg N ha^(-1)between the wheat and maize seasons under one-time presowing root-zone irrigation(W0)and additional jointing and anthesis irrigation(W2)in wheat and one irrigation after maize sowing were set as follows:N1(120:240),N2(180:180),N3(240:120)and N4(300:60).The results showed that under W0,the N3 treatment produced the highest annual yield,crop water productivity(WPC),and nitrogen partial factor productivity(PFPN).Increased N allocation in wheat under W0 improved wheat yield without affecting maize yield,as surplus nitrate after wheat harvest was retained in the topsoil layers and available for the subsequent *** W2,annual yield was largest in the N2 *** risk of nitrate leaching increased in W2 when N application rate in wheat exceeded that of the N2 treatment,especially in the wet *** to W2N2,the W0N3 maintained 95.2%grain yield over two *** WPCwas higher in the W0 treatment than in the W2 ***,following limited total N rate,an appropriate fertilizer N transfer from maize to wheat season had the potential of a“triple win”for high annual yield,WPCand PFPN in a water-limited wheat–maize cropping system.

关键词： Cropping system Water-saving irrigation North China Plain Nitrogen optimization Sustainable intensification

Effects of different energy levels in low-protein diet on liver lipid metabolism in the late-phase laying hens through the gut-liver axis

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Journal of Animal Science and Biotechnology 2024年第5期15卷 2122-2136页

作者： Hong Hu ying Huang Anjian li Qianhui Mi Kunping Wang liang Chen Zelong zhao Qiang Zhang Xi Bai Hongbin Pan Yunnan Provincial Key Laboratory of Animal Nutrition and Feed Science Faculty of Animal Science and TechnologyYunnan Agricultural UniversityKunming 650201China College of Animal Science Anhui Science and Technology UniversityBengbu 233000China State Key Laboratory of Animal Nutrition Institute of Animal SciencesChinese Academy of Agriculture SciencesBeijing 100193China Shanghai BIOZERON Biotechnology Co. LtdShanghai 201800China WOD Poultry Research Institute Beijing 100193China

Background The energy/protein imbalance in a low-protein diet induces lipid metabolism disorders in late-phase laying *** energy levels in the low-protein diet to adjust the energy-to-protein ratio may improve fat deposition,but this also decreases the laying performance of *** study investigated the mechanism by which different energy levels in the low-protein diet influences liver lipid metabolism in late-phase laying hens through the enterohepatic axis to guide feed optimization and nutrition strategies.A total of 288 laying hens were randomly allocated to the normal-energy and normal-protein diet group(positive control:CK)or 1 of 3 groups:lowenergy and low-protein diet(LL),normal-energy and low-protein diet(NL),and high-energy and low-protein diet(HL)*** energy-to-protein ratios of the CK,LL,NL,and HL diets were 0.67,0.74,0.77,and 0.80,*** Compared with the CK group,egg quality deteriorated with increasing energy intake in late-phase laying hens fed low-protein *** fed LL,NL,and HL diets had significantly higher triglyceride,total cholesterol,acetylCo A carboxylase,and fatty acid synthase levels,but significantly lower hepatic lipase levels compared with the CK *** transcriptome sequencing revealed that genes involved in fatty acid beta-oxidation(ACOX1,HADHA,EHHADH,and ACAA1)were downregulated,whereas genes related to fatty acid synthesis(SCD,FASN,and ACACA)were upregulated in LL group compared with the CK *** of the cecal microbiome showed that in hens fed an LL diet,Lactobacillus and Desulfovibrio were enriched,whereas riboflavin metabolism was *** metabolites that were most significantly affected by the LL diet included several vitamins,such as riboflavin(vitamin B2),pantethine(vitamin B5 derivative),pyridoxine(vitamin B6),and 4-pyridoxic *** A lipid metabolism disorder due to deficiencies of vitamin B2 and pantethine originating from the metabolism of the cecal microb

关键词： Cecal microbiome Energy/protein imbalance Late-phase laying hens laying hens liver lipid metabolism Low-protein diet Multi-omics