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Integrating high-volume molecular and morphological data into the evolutionary studies of Allium

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Plant Diversity 2024年第1期46卷 1-2页

作者： Xing-Jin he Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610065SichuanPR China

The genus Allium(Amaryllidaceae),which includes economically important plants such as onions,garlic,and leeks,is one of the most species-rich and diverse genera of monocotyledon plants in the Northern hemisphere(Govaerts et al.,2021),with approximately 1000 *** evolution of Allium is characterized by ecological diversification,with most species preferring open.

关键词： species evolutionary Allium

Unveiling a Novel Insulator-to-Metal Transition in La_(N)iO_(4+δ):Challenging High-Temperature Superconductivity Claimed for Single-Layer Lanthanum Nickelates

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Chinese Physics Letters 2024年第9期41卷 93-106页

作者： yunqi Ji Xiaohan Wang Xiaohe Li Wenting Tang Xinyang Li Xin Wang Fangfei Li Liang Li Qiang Zhou Synergetic Extreme Condition User Facility State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China

La_(2)NiO_(4)has a similar structure to La_(2)CuO_(4)and was proposed as a high-temperature superconductor based on magnetic-moment measurements decades ***,with the exception for electrical resistance drop behavior of about 4 orders of magnitude that is claimed to originate from the superconductivity ever observed in Sr-doped La_(N)iO_(4),most electrical data reported to date in La_(N)iO_(4)system exhibit a trivial insulating ground ***,we definitively identify the similar electrical resistance drop behavior of more than 3 orders of magnitude in La_(2)NiO_(4+δ).However,our extensive investigations reveal that this phenomenon is a novel insulatorto-metal transition,distinct from ***,compared to the weak magnetic-field effects,pressure can significantly suppress the transition and transform from the metallic to an insulating ground state,accompanied by an isostructural phase *** work not only elucidates the fundamental properties of the metallic conducting ground state in La_(N)iO_(4)+δ,but also critically challenges the notion of superconductivity in single-layer lanthanum nickelates.

关键词： resistance electrical metallic

Geoengineering: proactive measures to tackle climate change

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National Science Review 2024年第4期11卷 299-304页

作者：朱禾 the editorial office of NSR in Beijing

As of 20 August, 2023, extensive parts of northern China including the capital city of Beijing had experienced arguably the hottest summer in recent years, recording consecutive days of high temperatures at or near 40°C. Against this backdrop, National Science Review (NSR) organized a web forum on a climate-related topic that needs more exposure to Chinese public and researchers alike:geoengineering.

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Toxicity mechanisms of photodegraded polyvinyl chloride nanoplastics on pea seedlings

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 111-124页

作者： Hao Wu Beibei he Bocheng Chen An Liu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Nanoplasctics(NPs),which are very small in particle size,exert toxic effect to ***,compared to original NPs,photodegraded NPs would pose higher *** is because their relatively higher specific surface areas and the presence of additives which can more easily *** original NPs and aged NPs affect plant growth has not been widely *** work chose polyvinyl chloride NPs(PVC-NPs)that were subjected to up to 1000 h UV light radiation to explore the impact of PVC-NPs on the growth of pea seedlings(Pisum Sativum L.).The results indicated the existence of PVC-NPs with longer UV light radiation time and higher concentrations had more negative influences on pea seedlings’growth such as germination rate(decreased by 10.6%–22.5%),stem length(decreased by 2.8%–8.1%),dry weight(decreased by 6.3%–7.1%)and fresh weight(decreased by 6.7%–14.8%).It was also noted that photodegraded PVC-NPs resulted in damage to leaf stomata and roots,hindering photosynthesis and absorption of nutrients and hence the decrease in chlorophyll and soluble sugar *** to transcriptomic investigation results,the presence of aged PVC-NPs primarily influenced protein processing in endoplasmic reticulum(upregulated metabolic pathway)and phenylpropanoid biosynthesis(downregulated metabolic pathway)of pea *** results provide an in-depth understanding of how NPs influence the growth of plants.

关键词： Nanoplasctics Polyvinyl chloride Toxicity mechanisms Plant growth

Neural Stem Cell Competition

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Neuroscience Bulletin 2024年第2期40卷 277-279页

作者： Yanan Li Jie he State Key Laboratory of Neuroscience Institute of NeuroscienceCenter for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai 200031China University of Chinese Academy of Sciences Beijing 100049China

Cell competition is an adaptive surveillance mechanism to ensure the robustness of developmental outputs,maintain tissue integrity,and regulate tumor progression in multicellular organisms,which is highly conserved from invertebrates to vertebrates[1].At the cellular level,cell competition represents a non-cell-autonomous process in that cells can sense the fitness of their neighbors through cellular interactions,thereby eliminating low-fitness cells and expanding high-fitness counterparts,however,cells develop normally in homogenous populations.

关键词： thereby maintain eliminating

Designing novel adaptive dynamic event-triggered protocols for uncertain multi-agent systems

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Science China(Information Sciences) 2024年第1期67卷 310-311页

作者： Bin CheNG Bin he College of Electronics and Information Engineering Tongji University Frontiers Science Center for Intelligent Autonomous Systems

Multi-agent systems (MASs) have garnered widespread attention and have been investigated by numerous researchers in recent years, primarily due to their broad applications in industry, transportation, agriculture, and astronomy. While studying the cooperative control of MASs, numerous researchers place emphasis on reducing the frequency of communication among neighboring agents.

关键词： Directed graphs

Polymeric hollow fiber membrane for cooling crystallization seeding:On the mechanism of induced nucleation based on thermal transfer Author links open overlay panel

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Particuology 2024年第8期91卷 38-49页

作者： Zeman he Shaofu Du Guanying Shao Peiyu Li Lei Sheng Gaohong he Xiaobin Jiang Wu Xiao State Key Laboratory of Fine Chemicals School of Chemical EngineeringEngineering Laboratory for Petrochemical Energy-efficient Separation Technology of Liaoning ProvinceDalian University of TechnologyDalian 116024China

Cooling crystallization is an important separation process and particuology technology that requires accurate nucleation control ***,we introduced the polymeric hollow fiber membrane with proper thermal properties as the effective nucleation induction interface during cooling *** heterogeneous nucleation control mechanism was introduced based on classical nucleation theory and the thermal transfer *** properties and the thermal conductivity of two kinds of polymeric membranes,polytetrafluoroethylene(PTFE)and polyethersulfone(PES),were measured and simulated with the developed *** two membranes possessed different nucleation induction periods,nucleation rates and crystallization performances,which validated that the hollow fiber membrane module could effectively accelerate the nucleation process compared to conventional cooling crystallization owing to the shorter nucleation induction period and the reduced solution surface *** to the higher hydrophobicity and the lower roughness of the membrane surface,the PTFE membrane possessed a more moderate performance in generating stable heterogeneous nucleation than the one of PES ***,the adjustable membrane property enabled the hollow fiber membrane-assisted cooling crystallization to possess the accurate nucleation control and desired terminal particle products.

关键词： Cooling crystallization Nucleation Particle process Hollow fiber membrane Induction period Process control

No basalt accumulation and segregation atop the 660-km discontinuity beneath the Sea of Okhotsk

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Earth and Planetary Physics 2024年第4期8卷 621-631页

作者： BingXin Zhou XiaoBo he Marine Science and Technology College Zhejiang Ocean UniversityZhoushan Zhejiang 316022China

Recent seismic evidence shows that basalt accumulation is widespread in the mantle transition zone(MTZ),yet its ubiquity or sporadic nature remains *** investigate this phenomenon further,we characterized the velocity structure across the 660-km discontinuity that separates the upper mantle from the lower mantle beneath the Sea of Okhotsk by modeling the waveform of the S660P phase,a downgoing S wave converting into a P wave at the 660-km *** waves were excited by two regional>410-km-deep events and were recorded by stations in central *** findings showed no need to introduce velocity anomalies at the base of the MTZ to explain the S660P waveforms because the IASP91 model adequately reproduced the *** finding indicates that the basalt accumulation has not affected the bottom of the MTZ in the study ***,this discontinuity is primarily controlled by temperature or water content variations,or ***,we argue that the basalt accumulation at the base of the MTZ is sporadic,not ubiquitous,reflecting its heterogeneous distribution.

关键词： 660-km discontinuity S660P basalt segregation mantle transition zone western Pacific subduction zone

Recent progress on impact induced reaction mechanism of reactive alloys

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Defence Technology（防务技术） 2024年第7期37卷 69-95页

作者： Yansong Yang Chuanting Wang Yuanpei Meng Yue Ma Lei Guo Yuan he Zhichao Sun Yong he School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina

In recent years,in order to improve the destructive effectiveness of munitions,the use of new types of destructive elements is an important way to improve destructive *** a new type of reactive material,reactive alloy contains a large portion of reactive metal elements(Al,Mg,Ti,Zr,etc.),which breaks up under high-velocity impact conditions,generating a large number of high-temperature combustible fragments,which undergo a violent combustion reaction with *** with traditional metal polymers(Al-PTFE)and other reactive composites,it has higher density and strength,excellent mechanical properties and broader application ***,researchers have mainly investigated the impact energy release mechanism of reactive alloys through impact tests,and found that there are several important stages in the process of the material from fragmentation to reaction,i.e.,impact fragmentation of the material,rapid heating and combustion *** paper focuses on three problems that need to be solved in the impact-induced energy release process of reactive alloys,namely:the fragmentation mechanism and size distribution law of the fragments produced by the impact of the material on the target,the relationship between the transient temperatures and the size of the fragments,and the reaction temperatures and size thresholds of the fragments to undergo the chemical *** current status of the research of the above problems is reviewed,some potential directions to reveal the impact induced reaction mechanism of reactive alloy is discussed.

关键词： Reactive alloys Impact Fragmentation Mass and size distribution Shock temperature rise Adiabatic shear Combustion