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Volume and surface effects on two-photonic and three-photonic processes in dry co-doped upconversion nanocrystals

Nano Research 2022年第3期15卷 2362-2373页

作者： Bettina Grauel christian Würth christian Homann Lisa Krukewitt Elina Andresen Janina Roik sebastian Recknagel Markus Haase Ute Resch-Genger Federal Institute for Materials Research and Testing(BAM) Division 1.2 BiophotonicsRichard-Willstaetter-Str.1112489 BerlinGermany Federal Institute for Materials Research and Testing(BAM) Division 1.6 Inorganic Reference MaterialsRichard-Willstaetter-Str.1112489 BerlinGermany Institute of Chemistry of New Materials Department Biology/ChemistryUniversity OsnabrueckBarbarastr.749076 OsnabrueckGermany Department of Anesthesiology and Intensive Care Medicine University Medical Center RostockSchillingallee 3518057 RostockGermany

Despite considerable advances in synthesizing high-quality core/shell upconversion(UC)nanocrystals(NC;UCNC)and UCNC photophysics,the application of near-infrared(NIR)-excitable lanthanide-doped UCNC in the life and material sciences is still hampered by the relatively low upconversion luminescence(UCL)of UCNC of small size or thin protecting *** obtain deeper insights into energy transfer and surface quenching processes involving Yb^(3+) and Er^(3+) ions,we examined energy loss processes in differently sized solid core NaYF_(4) nanocrystals doped with either Yb^(3+)(YbNC;20%Yb^(3+))or Er^(3+)(ErNC;2%Er^(3+))and co-doped with Yb^(3+) and Er^(3+)(YbErNC;20%Yb^(3+) and 2%Er^(3+))without a surface protection shell and coated with a thin and a thick NaYF_(4) shell in comparison to single and co-doped bulk *** studies at 375 nm excitation demonstrate back-energy transfer(BET)from the ^(4)G_(11/2) state of Er^(3+) to the ^(2)F_(5/2) state of Yb^(3+),through which the red Er^(3+) ^(4)F_(9/2) state is efficiently *** power density(P)-dependent steady state and time-resolved photoluminescence measurements at different excitation and emission wavelengths enable to separate surface-related and volume-related effects for two-photonic and three-photonic processes involved in UCL and indicate a different influence of surface passivation on the green and red Er3+*** intensity and lifetime of the latter respond particularly to an increase in volume of the active UCNC *** provide a three-dimensional random walk model to describe these effects that can be used in the future to predict the UCL behavior of UCNC.

关键词： upconversion luminescence core/shell nanoparticles dopant concentration lifetime volume effect surface quenching

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signals from the interface:protein nanoclusters stabilize biomolecular condensates

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signal Transduction and Targeted Therapy 2022年第2期7卷 341-342页

作者： christian Hoffmann Branislava Rankovic Dragomir Milovanovic Laboratory of Molecular Neuroscience German Center for Neurodegenerative Diseases(DZNE)10117 BerlinGermany

In a recent study,Folkmann and colleagues1 show that protein nanoclusters at the surface of biomolecular condensates act as Pickering agents stabilizing these emulsions in *** accumulating evidence suggests that cytosol represents a complex emulsion where multiple membrane-bound organelles and biomolecular condensates co-exist together.2 Each of these condensates is a crucible that can enrich for numerous proteins,RNAs,and even the entire membrane-bound organelles,such as the cluster of synaptic vesicles or the Golgi *** molecules in these condensates remain highly mobile,readily exchange with the surrounding environment and grow/coarsening over time(by coalescence or Ostwald ripening),often towards the round structures to minimize the surface tension.

关键词： clusters molecular readily

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sINGULAR LIMITs FOR INHOMOGENEOUs EQUATIONs OF ELAsTICITY

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Acta Mathematica scientia 2009年第3期29卷 645-649页

作者：陆云光 christian Klingenberg Department of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 210016 China Department of Mathematics National University of ColombiaBogota Colombia Mathematisches Institut Universitt Würzburg Am Hubland 97074 Würzburg Germany

Based on the framework introduced in [4] or [5], the singular limits of stiff relaxation and dominant diffusion for the Cauchy problem of inhomogeneous equations of elasticity is studied. We are able to reach equilibr... 详细信息

关键词： relaxation limit equations of elasticity compensated compactness invariantregions theory

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Training load characteristics and injury and illness risk identification in elite youth ski racing:A prospective study

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Journal of sport and Health science 2021年第2期10卷 230-236页

作者： Carolin Hildebrandt Renate Oberhoffer christian Raschner Erich Muller christian Fink Lisa steidl-Muller Department of sport science University of InnsbruckInnsbruck 6020Austria Department of sport and Health science Preventative PediatricsTechnical University of MunichMunich 80992Germany Department of sport science and Kinesiology University of SalzburgSalzburg 5400Austria Gelenkpunktsports and Joint surgery Innsbruck 6020Austria

Purpose:The study aimed to investigate the role of training load characteristics and injury and illness risk in youth ski ***:The training load characteristics as well as traumatic injuries,overuse injuries,and illnesses of 91 elite youth ski racers(age=12.1±1.3 years,mean±sD)were prospectively recorded over a period of 1 season by using a sport-specific online *** linear regression analyses were performed to monitor the influence of training load on injuries and *** in mean training load characteristics between preseason,in-season,and post-season were calculated using multivariate analyses of ***:Differences were discovered in the number of weekly training sessions(p=0.005)between pre-season(4.97±1.57)and post-season(3.24±0.71),in the mean training volume(p=0.022)between in-season(865.8±197.8 min)and post-season(497.0±225.5 min)and in the mean weekly training intensity(Index)(p=0.012)between in-season(11.7±1.8)and post-season(8.9±1.7).A total of 185 medical problems were reported(41 traumatic injuries,12 overuse injuries,and 132 illnesses).The weekly training volume and training intensity was not a significant risk factor for injuries(p>0.05).Training intensity was found to be a significant risk factor for illnesses in the same week(β=0.348;p=0.044;R^(2)=0.121)and training volume represents a risk factor for illnesses in the following week(β=0.397;p=0.027;R^(2)=0.157).Conclusion:A higher training intensity and volume were associated with increased illnesses,but not with a higher risk of *** training and ensuring appropriate progression of training load between weeks may decrease incidents of illness in-season.

关键词： Health problems Injury and illness prevention Training load Youth ski racing

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An Approach for Adaptive Limbless Locomotion Using a CPG-Based Reflex Mechanism

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Journal of Bionic Engineering 2014年第3期11卷 389-399页

作者： Guoyuan Li Houxiang Zhang Jianwei Zhang hans Petter Hildre Faculty of Maritime Technology and Operations Aalesund University College Aalesund 6009 Norway Department of Computer science University of Hamburg Hamburg 22527 Germany

Animals＇ free movement in natural environments has attracted many researchers to explore control methods for bio-inspired robots. This paper presents a novel reflex mechanism based on a Central Pattern Generator （CPG） for adaptive locomotion of limbless robots. First, inspired by the concept of reflex arc, the reflex mechanism is designed on a connectionist CPG model. since the CPG model inspired by the spinal cord of lampreys is developed at the neuron level, it provides a possible natural solution for sensory reflex integration. Therefore, sensory neurons that bridge the external stimuli and the CPG model, together with the concept of reflex arc, are utilized for designing the sensory reflex mechanism. Then, a border reflex and a body reflex are further developed and applied on the ends and the middle part of a limbless robot, respectively. Finally, a ball hitting scenario and a corridor passing scenario are designed to verify the proposed method. Results of simulations and on-site experiments show the feasibility and effectiveness of the reflex mechanism in realizing fast response and adaptive limbless locomotion.

关键词： sensory reflex mechanism reflex arc central pattern generator limbless locomotion

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single-step Arbitrary Lagrangian-Eulerian Discontinuous Galerkin Method for 1-D Euler Equations

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Communications on Applied Mathematics and Computation 2020年第4期2卷 541-579页

作者： Jayesh Badwaik Praveen Chandrashekar christian Klingenberg Department of Mathematics University of WürzburgWürzburgGermany TIFR Center for Applicable Mathematics BangaloreIndia

We propose an explicit,single-step discontinuous Galerkin method on moving grids using the arbitrary Lagrangian-Eulerian approach for one-dimensional Euler *** grid is moved with the local fluid velocity modified by some smoothing,which is found to con-siderably reduce the numerical dissipation introduced by Riemann *** scheme preserves constant states for any mesh motion and we also study its positivity preservation *** grid refinement and coarsening are performed to maintain the mesh qual-ity and avoid the appearance of very small or large ***,higher order methods are developed and several test cases are provided to demonstrate the accuracy of the proposed scheme.

关键词： Discontinuous Galerkin method Moving meshes Arbitrary Lagrangian-Eulerian Euler equations

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Lithostructural controls in Douala-Buea Region landscape (sW Cameroon margin):Insights from morphometric analysis

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Journal of Mountain science 2021年第1期18卷 68-87页

作者： christian BALLA ATEBA sébastien OWONA Moussa NsANGOU NGAPNA Véronique MANGA TsIMI DieudonnéMINYEM Joseph MVONDO ONDOA Department of Earth sciences Faculty of Sciencethe University of DoualaDouala 24157Cameroon Department of Earth sciences Faculty of Sciencethe University of Yaounde IYaounde 812Cameroon Department of Mines and Quarries Faculty of Mining and Petroleum Industriesthe University of MarouaMaroua 814Cameroon

The Douala-Buea Region(DBR;4°-5°N,9°-10°30’E),a portion of the southern Cameroon passive margin,developed on the Proterozoic granito-gneissic basement and the Cretaceous to Recent volcanosedimentary cover,was explored in order to evaluate the lithology and tectonics controls on its landscape usingthequalitativeandquantitative geomorphological analyses based on 30 m resolution Digital Elevation Models(DEM)and field *** area displays an uneven and complex landscape differentiated into four morphological units:Douala,Nkondjock,Kumba and Buea *** Douala Unit corresponds to the Coastal Plain and is extended on the Douala-Kribi/*** Nkondjock Unit represents a middle plateau developed on a Proterozoic granito-gneissic *** Kumba Unit matches with the southernmost volcanic Western Cameroon High *** Buea Unit corresponds to the Mount Cameroon *** relief analysis through mountain-front sinuosity(smf,1.19–1.43)and relative relief ratio(Rr,0.10–2.31)vary from one unit to *** drainage network analysis including drainage patterns,stepped longitudinalriverprofiles,theassociated morphometric indexes,notably the concavity index(IC,0.56–0.88),deviation(D,267–2912 m),basin asymmetry factor(A_(F),6.37–42.12),hypsometric integral(HI,0.10–0.29),valley floor width to valley height ratio(V_(f),0.36–2.75),elongation ratio(R_(e),0.30–0.50),watershed slope(s,6.88–88.88)and stream length gradient index(sL,0–3332)vary from one basin to another *** results also show the heterogeneous and uneven DBR landscape controlled by its lithology and active *** drainage system reveals concave to concavo-convex longitudinal river profile shapes with knick points,asymmetric basins,and fault reactivations,and highlights the tectonics activity that used to occur through the time and their control on the ***,they document the lithostructural controls on the DBR landscape evolution,extendable in the whole

关键词： Morphometric indices Lithological control structural control Morphological units Douala-Buea Region sW Cameroon margin

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Direct Model Checking Matrix Algorithm

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Journal of Computer science & Technology 2006年第6期21卷 944-949页

作者：陶志红 hans Kleine Buening 王立福 Department of Computer science and Technology Peking University Beijing 100871 P.R. China Department of Computer science Paderborn University D-33095 Germany

During the last decade, Model Checking has proven its efficacy and power in circuit design, network protocol analysis and bug hunting. Recent research on automatic verification has shown that no single model-checking technique has the edge over all others in all application areas. so, it is very difficult to determine which technique is the most suitable for a given model. It is thus sensible to apply different techniques to the same model. However, this is a very tedious and time-consuming task, for each algorithm uses its own description language. Applying Model Checking in software design and verification has been proved very difficult. software architectures （sA） are engineering artifacts that provide high-level and abstract descriptions of complex software systems. In this paper a Direct Model Checking （DMC） method based on Kripke structure and Matrix Algorithm is provided. Combined and integrated with domain specific software architecture description languages （ADLs）, DMC can be used for computing consistency and other critical properties.

关键词： direct model checking (DMC) Kripke semantics structure CTL logic matrix algorithm

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Park size and prey density limit occurrence of Eurasian sparrowhawks in urban parks during winter

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Avian Research 2018年第3期9卷 206-213页

作者： Claudia schütz christian H.schulze Department of Botany and Biodiversity Research University of ViennaRennweg 141030 ViennaAustria

Background: Eurasian sparrowhawks(Accipiter nisus) increasingly represent successful city-dwellers. Thereby, a rich food supply indicated by high numbers of small birds is believed to be the key driver for this bird-eating raptor species to settle in urban environments. However, as small passerine birds show particularly strong antipredator responses, sparrowhawks may not simply focus on patches of highest prey densities, but rather respond strategically to prey behavior, raising the importance of other parameters in determining the occurrence within urban ***: To deepen our knowledge on habitat requirements of urban sparrowhawks, bird surveys were carried out during winter between December 2005 and January 2017 in 36 city parks in Vienna, Austria. Besides food supply also park size, canopy heterogeneity and the connectivity with other green spaces were ***: Occurrence of sparrowhawks was positively affected by increasing park size, prey density and the interaction between both. Bird feeder density and park connectivity with other green spaces were of minor importance in explaining the presence of this species. Canopy heterogeneity didn't affect city park occupancy by Eurasian ***: Our results suggest that large city parks, particularly when characterized by high prey densities, substantially contribute to protect and preserve ecologically important bird species such as raptors within the urban environment—a landscape already struggling with biodiversity losses and functional homogenization.

关键词： Birds of prey Bird feeders Prey abundance Habitat connectivity Tree cover Urban ecology

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A novel role for mitochondrial fission in macrophages: trained innate immunity induced by beta-glucan

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Cellular & Molecular Immunology 2023年第8期20卷 864-866页

作者： Anna Brichkina hans-Uwe simon Institute of systems Immunology Center for Tumor Biology and ImmunologyPhilipps University of Marburg35043MarburgGermany Member of the German Center for Lung Research(DZL) Philipps University of Marburg35043MarburgGermany Laboratory of Molecular Immunology Institute of Fundamental Medicine and BiologyKazan Federal University420012KazanRussia Institute of Pharmacology University of Bern3010BernSwitzerland Institute of Biochemistry Brandenburg Medical School16816NeuruppinGermany

In a recent paper published in Nature Immunology,Ding et *** new insights into the mechanism of how trained innate immunity could eradicate *** authors demonstrated that yeast-derived whole beta-glucan particles(WGP)increased the responsiveness of lung interstitial macrophages to tumor-derived factors associated with the subsequent inhibition of tumor metastasis through enhanced cytotoxicity to cancer *** authors identified the metabolic sphingolipid–mitochondrial fission axis in WGP-trained macrophages as the key pathway responsible for this phenomenon and categorized it as a mechanism of trained innate immunity[1].

关键词： subsequent insight immunity

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