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A Toughness Condition for Fractional(k, m)-deleted Graphs Revisited

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Acta Mathematica Sinica,English Series 2019年第7期35卷 1227-1237页

作者： Wei GAO Juan L.G.GUIRAO yao jun chen Department of Mathematics Nanjing University Nanjing 210093 P. R. China School of Information Science and Technology Yunnan Normal University Kunming 650500 P. R. China Departamento de Matematica Aplicada y Estadistica. Universidad Politecnica de Cartagena Hospital de Marina 30203-Cartagena Region de Murcia Spain

In computer networks, toughness is an important parameter which is used to measure the vulnerability of the network. Zhou et al. obtains a toughness condition for a graph to be fractional(k, m)-deleted and presents an example to show the sharpness of the toughness bound. In this paper, we remark that the previous example does not work and inspired by this fact, we present a new toughness condition for fractional(k, m)-deleted graphs improving the existing one. Finally, we state an open problem.

关键词： Graph fractional factor fractional(k,m)-deleted graph toughness

Sharp Isolated Toughness Bound for Fractional(k,m)-Deleted Graphs

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Acta Mathematicae Applicatae Sinica 2024年

作者： Wei GAO Wei-fan WANG yao-jun chen School of Information Science and Technology Yunnan Normal University Department of Mathematics Zhejiang Normal University Department of Mathematics Nanjing University

Long non-coding RNA SNHG16 promotes human placenta-derived mesenchymal stem cell proliferation capacity through the PI3K/AKT pathway under hypoxia

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World Journal of Stem Cells 2022年第9期14卷 714-728页

作者： Xu-Dong Feng Jia-Hang Zhou jun-yao chen Bing Feng Rui-Tian Hu Jian Wu Qiao-Ling Pan Jin-Feng Yang Jiong Yu Hong-Cui Cao State Key Laboratory for The Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesThe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina Department of Chemistry Duke UniversityDurhamNC 27708United States Jinan Microecological Biomedicine Shandong Laboratory Jinan 250117Shandong ProvinceChina Key Laboratory of Diagnosis and Treatment of Aging and Physic-chemical Injury Diseases of Zhejiang Province The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina

BACKGROUND The effect of hypoxia on mesenchymal stem cells(MSCs)is an emerging topic in MSC *** long non-coding RNAs(lncRNAs)and messenger RNAs(mRNAs)are reported to play a critical role in regulating the biological characteristics of MSCs,their specific expression and co-expression profiles in human placenta-derived MSCs(hP-MSCs)under hypoxia and the underlying mechanisms of lncRNAs in hP-MSC biology are *** To reveal the specific expression profiles of lncRNAs in hP-MSCs under hypoxia and initially explored the possible mechanism of lncRNAs on hP-MSC *** Here,we used a multigas incubator(92.5%N_(2),5%CO_(2),and 2.5%O_(2))to mimic the potential of *** sequencing technology was applied to identify the exact expression profiles of lncRNAs and mRNAs under *** We identified 289 differentially expressed lncRNAs and 240 differentially expressed mRNAs between the hypoxia and normoxia *** them,the lncRNA SNHG16 was upregulated under hypoxia,which was also validated by reverse transcription-polymerase chain ***16 was confirmed to affect hP-MSC proliferation rates using a SNHG16 knockdown ***16 overexpression could significantly enhance the proliferation capacity of hP-MSCs,activate the PI3K/AKT pathway,and upregulate the expression of cell cycle-related *** Our results revealed the specific expression characteristics of lncRNAs and mRNAs in hypoxiacultured hP-MSCs and that lncRNA SNHG16 can promote hP-MSC proliferation through the PI3K/AKT pathway.

关键词： Human placenta-derived mesenchymal stem cell Hypoxia Long non-coding RNAs Proliferation Mesenchymal stem cell

Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

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Neural Regeneration Research 2025年第5期20卷 1397-1398页

作者： Zhenyu chen Xue-jun Li Department of Biomedical Sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower *** is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

关键词： degeneration diseases hereditary

Emerging progress: photochemical transformation of nitroso compounds

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Science China Chemistry 2025年第1期68卷 118-133页

作者： Ze-Le chen Qiang-Qiang Li Armido Studer jun Xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials School of Chemistry & Chemical Engineering Anhui University Organisch-Chemisches Institut Universitat Münster

Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich *** versatile profile of these compounds allows them to function as electrophiles, nucleophiles, diradicals, and radical acceptors in diverse transformations. In recent years, notable progress has been made in harnessing photochemical reactions with nitroso compounds to prepare N,O-containing structures using mild and eco-friendly conditions. Various nitroso compounds like nitrosoarenes, acyloxy nitroso compounds, N-nitrosoamines and nitrites have received significant attention for their ability to introduce NO moieties into complex molecules that are otherwise difficult to access. In this review, we provide an overview of the recent advancements in the visible light-induced conversion of nitroso compounds, with particular emphasis on their role as bifunctional reagents and acceptors of radicals, carbenes and nitrenes.

关键词： nitroso compounds photochemistry radical reaction carbene transformation nitrosoarenes

Unveiling the promotion role of ZnO on Zn-Al spinel oxide for CO2 hydrogenation

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Journal of Energy Chemistry 2025年第1期100卷 18-25页

作者： Tongyao Wang Xinlong yao Lixin Liang Hongyu chen Pan Gao Guangjin Hou State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The Zn-Al spinel oxide stands out as one of the most active catalysts for high-temperature methanol synthesis from CO2hydrogenation. However, the structure–activity relationship of the reaction remains poorly understood due to challenges in atomic-level structural characterizations and analysis of reaction intermediates. In this study, we prepared two Zn-Al spinel oxide catalysts via coprecipitation（ZnAl-C）and hydrothermal（ZnAl-H） methods, and conducted a comparative investigation in the CO2hydrogenation reaction. Surprisingly, under similar conditions, ZnAl-C exhibited significantly higher selectivity towards methanol and DME compared to ZnAl-H. Comprehensive characterizations using X-ray diffraction（XRD）, Raman spectroscopy and electron paramagnetic resonance（EPR） unveiled that ZnAl-C catalyst had abundant ZnO species on its surface, and the interaction between the ZnO species and its ZnAl spinel oxide matrix led to the formation of oxygen vacancies, which are crucial for CO2adsorption and activation. Additionally, state-of-the-art solid-state nuclear magnetic resonance（NMR） techniques,including ex-situ and in-situ NMR analyses, confirmed that the surface ZnO facilitates the formation of unique highly reactive interfacial formate species, which was readily hydrogenated to methanol and DME. These insights elucidate the promotion effects of ZnO on the ZnAl spinel oxide in regulating active sites and reactive intermediates for CO2-to-methanol hydrogenation reaction, which is further evidenced by the significant enhancement in methanol and DME selectivity observed upon loading ZnO onto the ZnAl-H catalyst. These molecular-level mechanism understandings reinforce the idea of optimizing the ZnO-ZnAl interface through tailored synthesis methods to achieve activity-selectivity balance.

关键词： Reaction intermediates

Highly conductive and stable iodine doped argyrodite electrolyte for all-solid-state lithium batteries

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Journal of Energy Chemistry 2025年第1期100卷 50-58页

作者： Gaozhan Liu Jing Zhang Jing Yang Jinghui chen Xingyue Xiao Xiayin yao Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Lithium argyrodites with high ionic conductivity and low cost are considered as one of the most prospective solid electrolytes for all-solid-state lithium ***,the poor chemical stability and compatibility with lithium metal limit their ***,Li5.4PS4.4Cl1.4I0.2solid electrolyte with high ionic conductivity of 11.49 m S cm-1and improved chemical stability is synthesized by iodine *** ultra-thin Li5.4PS4.4Cl1.4I0.2membrane with thickness of 10μm can be obtained by wet coating process,exhibiting a high ionic conductivity of 2.09 mS cm-1and low areal resistance of 1.17Ω***,iodine doping could in-situ form LiI at the lithium/electrolyte interface and improve the critical current density of Li5.4PS4.4Cl1.6from 0.8 to 1.35 mA *** resultant LiCoO2/Li5.4PS4.4Cl1.4I0.2/Li battery shows excellent cycling stability at 1 C,with a reversible specific capacity of 110.1 mA h g-1and a retention of 80.5% after 1000 *** addition,the assembled LiCoO2/Li5.4PS4.4Cl1.4I0.2membrane/Li pouch cell delivers an initial discharge capacity of 110.4 mA h g-1and 80.5% capacity retention after 100 cycles.

关键词： Solid-State Batteries

冲击载荷作用下新型阻尼铝合金的阻尼及力学性能

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航空学报 2007年第3期28卷 735-738页

作者：姚俊臣文丽芳韩寿波马岳韩海军北京航空航天大学材料科学与工程学院北京100083

采用冲击实验装置研究了新型阻尼铝合金材料在冲击载荷作用下的动态力学性能及表征方法。研究结果表明:采用冲击实验的冲击功及能量参数能够科学合理地表征铝合金材料的力学及阻尼性能。新型阻尼铝合金材料的抗冲击载荷能力和阻尼性能... 详细信息

采用冲击实验装置研究了新型阻尼铝合金材料在冲击载荷作用下的动态力学性能及表征方法。研究结果表明:采用冲击实验的冲击功及能量参数能够科学合理地表征铝合金材料的力学及阻尼性能。新型阻尼铝合金材料的抗冲击载荷能力和阻尼性能均高于普通铸造铝合金材料86%及37%左右,且内部组织致密、均匀细小,具有优良的综合性能。

关键词：铝合金力学性能阻尼冲击载荷

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