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Induced Subgraphs with Large Degrees at End-vertices for Hamiltonicity of Claw-free Graphs

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Acta Mathematica Sinica,English Series 2016年第7期32卷 845-855页

作者： Roman CADA Bin Long LI Bo NING Sheng Gui ZHANG Department of Mathematics University of West Bohemia centre of excellence ITI - Institute for Theoretical Computer Science Charles University european centre of excellence ntis - New Technologies for the Information Society P.O. Box 314 306 14 Pilsen Czech Republic Department of Applied Mathematics Northwestern Polytechnical University Xi'an 710072 P. R. China Center for Applied Mathematics Tianjin University Tianjin 300072 P. R. China

A graph is called claw-free if it contains no induced subgrapn lsomorpmc to K1,3. Matthews and Sumner proved that a 2-connected claw-free graph G is Hamiltonian if every vertex of it has degree at least （[V（G）I - 2）/3. At the workshop CSzC （Novy Smokovec, 1993）, Broersma conjectured the degree condition of this result can be restricted only to end-vertices of induced copies of N （the graph obtained from a triangle by adding three disjoint pendant edges）. Fujisawa and Yamashita showed that the degree condition of Matthews and Sumner can be restricted only to end-vertices of induced copies of Z1 （the graph obtained from a triangle by adding one pendant edge）. Our main result in this paper is a characterization of all graphs H such that a 2-connected claw-free graph G is Hamiltonian if eachend-vertex of every induced copy of H in G has degree at least IV（G）I/3 ＋ 1. This gives an affirmative solution of the conjecture of Broersma up to an additive ***-vertex of every induced copy of H in G has degree at least IV（G）I/3 ＋ 1. This gives an affirmative solution of the conjecture of Broersma up to an additive constant.

关键词： Induced subgraph large degree end-vertex claw-free graph Hamiltonian graph

Efficient Handling of Lock Hand-off in DSM Multiprocessors with Buffering Coherence Controllers

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Journal of Computer Science & Technology 2012年第1期27卷 75-91页

作者： Benjamín Sahelices Agustín de Dios Pablo Ibáez Víctor Vials-Yúfera José María Llabería Computer Science Department and HiPEAC european Network of excellence University of Valladolid Valladolid Spain Computer Science and Systems Engineering Department I3A Research Institute and HiPEAC European Network of Excellence University of Zaragoza Zaragoza Spain Computer Architecture Department and HiPEAC european Network of excellence Polytechnic University of Catalua Barcelona Spain

Synchronization in parallel programs is a major performance bottleneck in multiprocessor systems. Shared data is protected by locks and a lot of time is spent on the competition arising at the lock hand-off. In order to be serialized, requests to the same cache line can either be bounced （NACKed） or buffered in the coherence controller. In this paper, we focus mainly on systems whose coherence controllers buffer requests. In a lock hand-off, a burst of requests to the same line arrive at the coherence controller. During lock hand-off only the requests from the winning processor contribute to progress of the computation, since the winning processor is the only one that will advance the work. This key observation leads us to propose a hardware mechanism we call request bypassing, which allows requests from the winning processor to bypass the requests buffered in the coherence controller keeping the lock line. We present an inexpensive implementation of request bypassing that reduces the time spent on all the execution phases of a critical section （acquiring the lock, accessing shared data, and releasing the lock） and which, as a consequence, speeds up the whole parallel computation. This mechanism requires neither compiler or programmer support nor ISA or coherence protocol changes. By simulating a 32-processor system, we show that using request bypassing does not degrade but rather improves performance in three applications with low synchronization rates, while in those having a large amount of synchronization activity （the remaining four）, we see reductions in execution time and in lock stall time ranging from 14% to 39% and from 52% to 7170, respectively. We compare request bypassing with a previously proposed technique called read combining and with a system that bounces requests, observing a significantly lower execution time with the bypassing scheme. Finally, we analyze the sensitivity of our results to some key hardware and software parameters.

关键词： distributed shared memory multiprocessors synchronization buffer coherence controller request bypass

Bimetallic Single‑Atom Catalysts for Water Splitting

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Nano-Micro Letters 2025年第1期17卷 1-45页

作者： Megha A.Deshmukh Aristides Bakandritsos Radek Zbořil Nanotechnology centre Centre for Energy and Environmental TechnologiesVŠB–Technical University of Ostrava17.listopadu 2172/1570800 Ostrava‑PorubaCzech Republic Regional centre of Advanced Technologies and Materials Czech Advanced Technology and Research Institute(CATRIN)Palacky University OlomoucŠlechtitelů241/2778371 Olomouc–HoliceCzech Republic

Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent *** field of catalysis has been revolutionized by single-atom catalysts(SACs),which exhibit unique and intricate interactions between atomically dispersed metal atoms and their ***,bimetallic SACs(bimSACs)have garnered significant attention for leveraging the synergistic functions of two metal ions coordinated on appropriately designed *** offer an avenue for rich metal–metal and metal–support cooperativity,potentially addressing current limitations of SACs in effectively furnishing transformations which involve synchronous proton–electron exchanges,substrate activation with reversible redox cycles,simultaneous multi-electron transfer,regulation of spin states,tuning of electronic properties,and cyclic transition states with low activation *** review aims to encapsulate the growing advancements in bimSACs,with an emphasis on their pivotal role in hydrogen generation via water *** subsequently delve into advanced experimental methodologies for the elaborate characterization of SACs,elucidate their electronic properties,and discuss their local coordination ***,we present comprehensive discussion on the deployment of bimSACs in both hydrogen evolution reaction and oxygen evolution reaction,the two half-reactions of the water electrolysis process.

关键词： Single-atom catalysts Single-atom dimers Hydrogen evolution Oxygen evolution Water splitting

Flexible Ti-Ni-N Thin Films Prepared by Magnetron Sputtering

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材料科学与工程（中英文A版） 2014年第1期4卷 27-33页

作者： Jindrich Musil Richard Jilek Radomir Cerstvy Department of Physics and New Technologies for Information Society (ntis) European Centre of Excellence Faculty of AppliedSciences University of West Bohemia CZ-306 14 Plzeh Czech Republic

Photoluminescence of SiV centers in CVD diamond particles with specific crystallographic planes

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Chinese Physics B 2019年第1期28卷 470-477页

作者： Ying-Shuang Mei Cheng-Ke Chen Mei-Yan Jiang Xiao Li Yin-Lan Ruan Xiao-Jun Hu College of Materials Science and Engineering Zhejiang University of Technology ARC centre of excellence in Nanoscale Biophotonics Institute of Photonics and Advanced Sensing University of Adelaide

We prepared the isolated micrometer-sized diamond particles without seeding on the substrate in hot filament chemical vapor deposition. The diamond particles with specific crystallographic planes and strong silicon-vacancy(SiV) photoluminescence(PL) have been prepared by adjusting the growth pressure. As the growth pressure increases from 2.5 to 3.5 kPa,the diamond particles transit from composite planes of {100} and {111} to only smooth {111} planes. The {111}-faceted diamond particles present better crystal quality and stronger normalized intensity of SiV PL with a narrower bandwidth of 5 nm. Raman depth profiles show that the SiV centers are more likely to be formed on the near-surface areas of the diamond particles, which have poorer crystal quality and greater lattice stress than the inner areas. Complex lattice stress environment in the near-surface areas broadens the bandwidth of SiV PL peak. These results provide a feasible method to prepare diamond particles with specific crystallographic planes and stronger SiV PL.

关键词： diamond particle SiV center photoluminescence crystallographic planes

Indirect printing of hierarchical patient-specific scaffolds for meniscus tissue engineering

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Bio-Design and Manufacturing 2019年第4期2卷 225-241页

作者： Joao BCosta Joana Silva-Correia Sandra Pina Alain da Silva Morais Sílvia Vieira Hélder Pereira Joao Espregueira-Mendes Rui LReis Joaquim M.Oliveira B′s Research Group I3Bs-Research Institute on BiomaterialsBiodegradables and BiomimeticsUniversity of MinhoHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineAveParkZona Industrial da Gandra4805-017 Barco GmrPortugal ICVS/3B’s-PT Government Associate Laboratory Braga/GuimaraesPortugal The Discoveries centre for Regenerative and Precision Medicine Headquarters at University of MinhoAvepark4805-017 BarcoGuimar'sPortugal Ripoll y De Prado Sports Clinic:Murcia-Madrid FIFA Medical centre of excellence MurciaSpain Orthopedic Department Centro Hospitalar Póvoa de Varzim Vila do CondePortugal Clínica do Dragao Espregueira-Mendes Sports CentreFIFA Medical Centre of ExcellencePortoPortugal Dom Henrique Research centre PortoPortugal Orthopedic Department University of MinhoBragaPortugal

The complex meniscus tissue plays a critical role in the knee. The high susceptibility to injury has led to an intense pursuit for better tissue engineering regenerative strategies, where scaffolds play a major role. In this study, indirect printed hierarchical multilayered sca ffolds composed by a silk fibroin (SF) upper layer and an 80/20 (w/w) ratio of SF/ionic-doped β-tricalcium phosphate (TCP) bottom layer were developed. Furthermore, a comparative analysis between two types of sca ffolds pro- duced using di fferent SF concentrations, i.e., 8% (w/v) (Hi8) and 16% (w/v) (Hi16) was performed. In terms of architecture and morphology, the produced sca ffolds presented homogeneous porosity in both layers and no di fferences were observed when comparing both sca ffolds. A decrease in terms of mechanical performance of the sca ffolds was observed when SF concentration decreased from 16 to 8% (w/v). Hi16 revealed a static compressive modulus of 0.66 ± 0.05 MPa and dynamical mechanical properties ranging from 2.17 ± 0.25 to 3.19 ± 0.38 MPa. By its turn, Hi8 presented a compressive modulus of 0.27 ± 0.08 MPa and dynamical mechanical properties ranging from 1.03 ± 0.08 MPa to 1.56 ± 0.13 MPa. In vitro bioactivity studies showed formation of apatite crystals onto the surface of Hi8 and Hi16 bottom layers. Human meniscus cells (hMCs) and human primary osteoblasts were cultured separately onto the top layer (SF8 and SF16) and bottom layer (SF8/TCP and SF16/TCP) of the hierarchical sca ffolds Hi8 and Hi16, respectively. Both cell types showed good adhesion and proliferation as denoted by the live/dead staining, Alamar Blue assay and DNA quanti fication analysis. Subcutaneous implantation in mice revealed weak in flammation and sca ffold’s integrity. The hierarchical indirect printed SF sca ffolds can be promising candidate for meniscus TE sca ffolding applications due their suitable mechanical properties, good biological performance and possibility of being applied in a patie

关键词： Patient-specific Indirect printing Hierarchical Silk fibroin Enzymatic-cross-linking Meniscus

CO2 degassing and melting of metasomatized mantle lithosphere during rifting-Numerical study

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Geoscience Frontiers 2019年第4期10卷 1409-1420页

作者： Weronika Gorczyk Christopher M. Gonzalez University of Western Australia Centre for Exploration TargetingSchool of Earth SciencesARC Centre of Excellence for Core to Crust Fluid SystemsPerthWestern AustraliaAustralia School of Earth Atmosphere and EnvironmentMonash University ClaytonMelbourneVICAustralia

:Reactivation of metasomatized mantle lithosphere may occur during continental extension,which is an important component of plate *** lower most part of the metasomatized domains in the subcontinental mantle lithosphere can be locally enriched in ***,partial melting of these metasomatized domains may play a crucial role in the global carbon ***,little is known about this process and up until now few numerical constraints are *** we address this knowledge gap and use a 2-D high resolution petrological-thermomechanical model to assess lithospheric ***2 degassing and *** test 4 lithospheric thicknesses:90,110,130 and 200 km with a 10 km thick metasomatized layer at the base using CO2 of 2 wt.%in the bulk *** carbonate enriched layer is stable below^3 GPa(>110 km)for a temperature of 1300℃;therefore,we only observe degassing patterns for lithospheric models that are 130 km and 200 km *** metasomatized layer for the 130 km thick lithosphere mostly comprises carbonatite melting,whereas in the 200 km thick scenario propagation of melt development from kimberlites to carbonatites occurs as the metasomatic mantle is exhumed during *** numerical models fit well into natural rifting zones of the european Cenozoic Rift System for young(shallow)and of the North Atlantic Rift for old(thick)lithosphere.

关键词： Rifting Mantle CO2 degassing Carbonate melting

Synthesis of strong SiV photoluminescent diamond particles on silica optical fiber by chemical vapor deposition

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Chinese Physics B 2018年第3期27卷 481-486页

作者： Zongchun Yang Yingshuang Mei Chengke Chen Yinlan Ruan Xiaojun Hu College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China ARC centre of excellence in Nanoscale Biophotonics Institute of Photonics and Advanced SensingThe University of AdelaideAdelaideSA 5005Australia

The separated silicon-vacancy(SiV)photoluminescent diamond particles were synthesized on a silica optical fiber by hot filament chemical vapor deposition(HFCVD).The effects of the pre-treated method and chamber pressure on the microstructure and photoluminescence of the diamond particles were *** results show that the diamond particles are homogeneously distributed on the surface of the optical *** the chamber pressure increasing from 1.6 kPa to 3.5 kPa,the shape of the particles transforms from flake to circle,while the diamond particles cannot be deposited on the fiber with the pressure further increased to 4.5 *** samples synthesized under 2.5 kPa chamber pressure are composed of diamond particles with size around 200-400 nm,exhibiting stronger SiV photoluminescence with the width of around 6 nm.

关键词： diamond silicon vacancy photoluminescence optical fiber

Lexical Tones and Word Learning in Mandarin-Speaking Children at Three Years of Age(Invited paper)

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Journal of Electronic Science and Technology 2017年第1期15卷 25-32页

作者： Wei-Yi Ma Peng Zhou Stephen Crain Li-Qun Gao ARC centre of excellence in Cognition and its Disorders Macquarie UniversitySydney 2109Australia Department of Foreign Languages and Literature Tsinghua UniversityBeijing 100084China centre for Speech Language and the BrainBeijing Language and Culture UniversityBeijing 10083China.

Unlike Indo-european languages,Mandarin relies heavily on lexical tones to distinguish word identity. Using the intermodal preferential looking paradigm, this study examined 3-year-old Mandarinspeakers＇ ability to use Mandarin lexical tones in learning new words. Results showed that when children were presented with Tone 2（rising） and Tone 4（falling）pairs, children successfully learned both ***, when children were presented with Tone 2and Tone 3（dipping） pairs, they learned the Tone 2word but not the Tone 3 one. Children were then divided into two groups based on their learning performance on the Tone 3 word. Successful learning of Tone 3 words was observed in the high performers but not in the low performers, who consistently misused Tone 3 as Tone 2. This study showed that Mandarinspeaking 3-year-olds could use lexical tones to learn words under experimental conditions, and that the difficulty of Tone 3 acquisition may be related to its lower level of perceptual distinctiveness compared with other tones.

关键词： lexical children speaking learned looking speakers distinguish consistently pronunciation perceptual