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Relaxation Schemes for the M1 Model with Space-Dependent Flux:Application to Radiotherapy Dose Calculation

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Communications in Computational Physics 2016年第1期19卷 168-191页

作者： Teddy Pichard Denise Aregba-Driollet Stephane Brull Bruno Dubroca martin frank Centre Lasers Intenses et Applications Universite de Bordeaux351 cours de la liberationTalence33400France Mathematics division Center for Computational Engineering ScienceRheinisch-Westf¨alische Technische HochschuleSchinkelstrasse 2Aachen52062Germany Institut de Mathematiques de Bordeaux Universite de Bordeaux351 cours de la liberationTalence33400France

Because of stability constraints,most numerical schemes applied to hyperbolic systems of equations turn out to be costly when the flux term is multiplied by some very large *** problem emerges with the M_(1)system of equations in the field of radiotherapy when considering heterogeneous media with very disparate ***,the flux term of the M_(1)system is non-linear,and in order for the model to be well-posed the numerical solution needs to fulfill conditions called *** this paper,we propose a numerical method that overcomes the stability constraint and preserves the realizability *** this purpose,we relax the M_(1)system to obtain a linear flux *** we extend the stencil of the difference quotient to obtain *** scheme is applied to a radiotherapy dose calculation example.

关键词： Radiotherapy Moments models relaxation models method of characteristics

Interaction of the α2A domain of integrin with small collagen fragments

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Protein & Cell 2010年第4期1卷 393-405页

作者： Hans-Christian Siebert Monika Burg-Roderfeld Thomas Eckert Sabine Stötzel Ulrike Kirch Tammo Diercks martin J.Humphries martin frank Rainer Wechselberger Emad Tajkhorshid Steffen Oesser Institut für Biochemie und Endokrinologie Veterinärmedizinische FakultätJustus-Liebig-Universität GießenFrankfurter Str.10035392 GießenGermany CiC bioGUNE Parque Tecnológico de BizkaiaEdificio 80048160 DerioSpain Utrecht Facility for High-resolution NMR Bijvoetcenter for Biomolecular Research Utrecht UniversityPadualaan 83584CH UtrechtThe Netherlands Wellcome Trust Centre for Cell-Matrix Research School of Biological SciencesUniversity of Manchester2.205 Stopford BuildingOxford RoadManchester M139PTUK Molecular Structure Analysis Core Facility Deutsches KrebsforschungszentrumIm Neuenheimer Feld 28069120 HeidelbergGermany Department of Biochemistry Beckman Instituteand Center for Biophysics and Computational BiologyUniversity of Illinois at Urbana-ChampaignUrbanaILUSA Collagen Research Institute Schauenburgerstr.116D-24118 KielGermany

We here present a detailed study of the ligand-receptor interactions between single and triple-helical strands of collagen and the α2A domain of integrin(α2A),providing valuable new insights into the mechanisms and dynamics of collagen-integrin binding at a sub-molecular *** occurrence of single and triple-helical strands of the collagen fragments was scrutinized with atom force microscopy(AFM)*** interactions of the triple-stranded fragments comparable to those of collagen can only be detected for the 42mer triple-helical collagen-like peptide under study(which contains 42 amino acid residues per strand)by solid phase assays as well as by surface plasmon resonance(SPR)***,changes in NMR signals during titration and characteristic saturation transfer difference(STD)NMR signals are also detectable whenα2A is added to a solution of the 21mer single-stranded collagen *** dynamics(MD)simulations employing different sets of force field parameters were applied to study the interaction between triple-helical or single-stranded collagen fragments withα*** is remarkable that even single-stranded collagen fragments can form various complexes withα2A showing significant differences in the complex stability with identical *** results of MD simulations are in agreement with the signal alterations in our NMR experiments,which are indicative of the formation of weak complexes between single-stranded collagen andα2A in *** results provide useful information concerning possible interactions ofα2A with small collagen fragments that are of relevance to the design of novel therapeutic A-domain inhibitors.

关键词： integrin-collagen interaction NMR SPR AFM molecular modeling

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SCARA机器人用密封环粘接金属部件

现代制造 2014年第38期 70-71页

作者： frank martin

对于新机器来说，用密封环来粘接金属部件更具经济性。在将近200℃的条件下，可以用一种特殊的树脂材料将两个部件连接在一起。在隔温条件下，在两台SCARA机器人的粘合工位完成金属部件的粘接工序。

关键词： SCARA机器人金属部件密封环粘接树脂材料经济性

Heart rate response and recovery during exercise predict future delirium risk——A prospective cohort study in middle-to older-aged adults

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Journal of Sport and Health Science 2023年第3期12卷 312-323页

作者： Lei Gao Aden Gaba Peng Li Richa Saxena frank A.J.LScheer Oluwaseun Akeju martin K.Rutter Kun Hu Department of Anesthesia Critical Care and Pain MedicineMassachusetts General HospitalHarvard Medical SchoolBostonMA 02114USA Medical Biodynamics Program Brigham and Women's HospitalBostonMA 02115USA Division of Sleep Medicine Harvard Medical SchoolBostonMA 02115USA Broad Institute of Massachusetts Institute of Technology and Harvard CambridgeMA 02142USA Center for Genomic Medicine Massachusetts General HospitalBostonMA 02114USA Division of Diabetes Endocrinology and GastroenterologySchool of Medical SciencesFaculty of BiologyMedicine and HealthManchester Academic Health Science CentreUniversity of ManchesterManchester M139PLUK Diabetes Endocrinology and Metabolism CentreManchester University National Health Service Foundation TrustManchester M139WLUK

Background:Delirium is a neurocognitive disorder characterized by an abrupt decline in attention,awareness,and cognition after surgical/illness-induced stressors on the *** is now an increasing focus on how cardiovascular health interacts with neurocognitive disorders given their overlapping risk factors and links to subsequent dementia and *** common indicator for cardiovascular health is the heart rate response/recovery(HRR)to exercise,but how this relates to future delirium is ***:Electrocardiogram data were examined in 38,740 middle-to older-aged UK Biobank participants(mean age=58.1 years,range:40-72 years;47.3%males)who completed a standardized submaximal exercise stress test(15-s baseline,6-min exercise,and 1-min recovery)and required hospitalization during *** HRR index was derived as the product of the heart rate(HR)responses during exercise(peak/resting HRs)and recovery(peak/recovery HRs)and categorized into low/average/high groups as the bottom quartile/middle 2 quartiles/top quartile,*** between 3 HRR groups and new-onset delirium were investigated using Cox proportional hazards models and a2-year landmark analysis to minimize reverse *** factors,lifestyle factors/physical activity,cardiovascular risk,comorbidities,cognition,and maximal workload achieved were included as ***:During a median follow-up period of 11 years,348 participants(9/1000)newly developed *** with the high HRR group(16/1000),the risk for delirium was almost doubled in those with low HRR(hazard ratio=1.90,95%)confidence interval(95%CI):1.30-2.79,p=0.001)and average HRR(hazard ratio=1.54,95%CI:1.07-2.22,p=0.020)).Low HRR was equivalent to being 6 years older,a current smoker,or>3 additional cardiovascular disease *** were robust in sensitivity analysis,but the risk appeared larger in those with better cognition and when only postoperative delirium was considered(n=1

关键词： Brain health Delirium Exercise stress test UK Biobank

A crowd-sourced genomic project to assess hybrid content in a rare avian vagrant(Azure Tit Cyanistes cyanus(Pallas,1770))

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Avian Research 2023年第4期14卷 545-552页

作者： martin Irestedt Filip Thorn Per G.P.Ericson Hein van Grouw Yaroslav A.Red'kin Alexander Hellquist frank Johansson Johan A.A.Nylander Department of Bioinformatics and Genetics Swedish Museum of Natural HistoryStockholmSweden Department of Zoology Stockholm University Sweden Bird Group Department of Life SciencesNatural History MuseumTringUnited Kingdom Zoological Museum Lomonosov Moscow State UniversityMoscowRussia Institute of Biological Problems of Cryolithozone SB RAS YakutskRussia Department of Women's and Children's Health Uppsala UniversitySweden Department of Ecology and Genetics Uppsala UniversityUppsalaSweden

The aim of this study was to correlate plumage variation with the amount of genomic hybrid content in hybrids between Azure Tits Cyanistes cyanus(Pallas,1770)and European Blue Tit Cyanistes caeruleus(Linnaeus,1758),by re-sequencing the genomes of museum specimens of non-hybrids and presumed hybrids with varying *** project was funded by crowdsourcing and initiated when two presumed Azure Tits,observed by hundreds of Swedish birdwatchers,were rejected as hybrids based on minor plumage deviations assumed to indicate hybrid contents from the European Blue *** results confirm that hybrids with intermediate plumages,so called Pleske’s Tits,are first generation hybrids(F1 hybrids).Individuals,whose plumages are similar to Azure Tits,but assessed as hybrids based on minor plumage deviations,are all backcrosses but vary in their degree of hybrid ***,some individuals morphologically recognized as pure Azure Tits expressed similar degrees of hybrid *** results indicate that:(1)hybrid content may be widespread in Azure Tits in the western part of its habitat distribution;(2)plumage deviation in backcrosses is not linearly correlated with the genetic degree of hybrid origin;and(3)all Azure Tits observed in Europe outside its natural distribution may have some degree of hybrid *** therefore suggest that it is very difficult to phenotypically single out hybrids beyond first generation *** argue that decreased sequencing costs and improved analytical tools open the doors for museomic crowd-sourced projects that may not address outstanding biological questions but have a major interest for lay citizens such as birdwatchers.

关键词： Crowdsourcing Cyanistes cyanus Hybridization Museomics

Protease activated receptor 2 and epidermal growth factor receptor are involved in the regulation of human sperm motility

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Asian Journal of Andrology 2007年第5期9卷 690-696页

作者： Karina Zitta martin Albrecht Stephan Weidinger Artur Mayerhofer frank Koehn Department of Dermatology and Allergy Technical University Munich Biedersteiner Strasse 29 Munich 80802 Germany Institute of Anatomy Ludwig-Maximilians-University Biedersteiner Strasse 29 Munich 80802 Germany

Aim： To investigate mechanisms of tryptase-induced reduction of sperm motility and explore whether epidermal growth factor receptor （EGF-R） and protease activated receptor 2 （PAR-2）- associated pathways are involved. Methods： Fresh semen was collected from healthy donors （n = 15）. Semen parameters and quality were assessed in accordance with the World Health Organization （WHO） criteria. Swim-up sperm were fixed and subjected to immunocytochemistry and immunoelectronmicroscopy with specific antibodies directed against PAR-2 and EGF-R. Protein extractions from swim-up spermatozoa were analyzed by Western blotting with antibodies for both receptors. Motility of spermatozoa was evaluated by computer-assisted semen analysis. Results： Immunocytochemistry found PAR-2 and EGF-R in approximately 30% of examined human ejaculated spermatozoa. Both receptors were localized in the plasma membrane. Like tryptase, the PAR-2 synthetic agonist SLIGKV reduced sperm motility, and this effect was inhibited by application of two specific EGF-R pathway blockers （AG1478 and PD168393）. Conclusion： The observed reduction of sperm motility by tryptase through the PAR-2 receptor involves EGF-R pathways.

关键词： spermatozoa motility epidermal growth factor receptor protease activated receptor

Electrical properties and microstructure formation of V/Al-based n-contacts on high Al mole fraction n-AlGaN layers

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Photonics Research 2020年第8期8卷 1381-1387页

作者： LUCA SULMONI frank MEHNKE ANNA MOGILATENKO martin GUTTMANN TIM WERNICKE MICHAEL KNEISSL Institut für Festkorperphysik Technische Universitat Berlin10623 BerlinGermany Ferdinand-Braun-Institut Leibniz-Institut fur Höchstfrequenztechnik12489 BerlinGermany Institut für Physik Humboldt Universität zu Berlin12489 BerlinGermany

The electrical and structural properties of V/Al-based n-contacts on n‐AlxGa1−xN with an Al mole fraction x ranging from x=0.75 to x=0.95 are *** n-contacts are obtained up to x=0.75 with a contact resistivity of 5.7×10^−4Ω·cm^2 whereas for higher Al mole fraction the IV characteristics are *** electron microscopy reveals a thin crystalline AlN layer formed at the metal/semiconductor interface upon thermal *** analysis confirmed an Al enrichment at the *** interfacial nitride-based layer in n-contacts on n‐Al0.9Ga0.1N is partly amorphous and heavily contaminated by *** role and resulting limitations of Al in the metal stack for n-contacts on n-AlGaN with very high Al mole fraction are ***,ultraviolet C(UVC)LEDs grown on n‐Al0.87Ga0.13N and emitting at 232 nm are fabricated with an operating voltage of 7.3 V and an emission power of 120μW at 20 mA in cw operation.

关键词： AlGaN fraction properties

Contrasting responseS of hoverflies and wild bees to habitat structure and land use change in a tropical landscape （southern Yunnan, SW China）

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Insect Science 2012年第6期19卷 666-676页

作者： Ling-Zeng Meng Konrad martin Jing-Xin Liu frank Burger Jin Chen University of Hohenheim Institute of Plant Production and Agroecology in the Tropics and Subtropics(380b)StuttgartGermany Xishuangbanna Tropical Botanical Garden the Chinese Academy of SciencesMenglaYunnan 666303China Natural History Museum of Erfurt Germany

The response of insects to monoculture plantations has mainly proceeded at the expense of natural forest areas, and is an outstanding and important issue in ecology and conservation biology, with pollination services declined around the world. In this study, species richness and distribution of hoverfly and wild bee communities were investigated in a changing tropical landscape in southern Yunnan, south-west China by Malaise traps periodically from 2008 to 2009. Species were recorded from the traditional land use types （natural forest, grassland, shrubland and rice field fallows）, and from recently established rubber plantations of different ages. Hoverflies （total 53 species） were most common in young successional stages of vegetation, including rice field fallow and shrubland. Species richness was highest in rice field fallows and lowest in forests and showed a highly significant relationship with the number of forb species and ground vegetation cover. In contrast, the highest richness of wild bees （total 44 species） was recorded from the natural forest sites, which showed a discrete bee community composition compared to the remaining habitat types. There was no significant relationship between the bee species richness and the environmental variables, including the numbers of different plant life forms, coverage of canopy and ground vegetation, successional age of vegetation and land use type. At the landscape scale, open land use systems, including young rubber plantations, are assumed to increase the species richness of hoverflies; however, this might decrease wild bee diversity. The present land use change by rubber cultivation can be expected to have negative impacts on the native wild bee communities.

关键词： Apidae insects pollinators rubber plantations Syrphidae tropical forest

Spatio-temporal evolution of Allium L. in the Qinghaie-Tibet-Plateau region: Immigration and in situ radiation

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Plant Diversity 2017年第4期39卷 167-179页

作者： frank Hauenschild Adrien Favre Jan Schnitzler Ingo Michalak martin Freiberg Alexandra N. Muellner-Riehl Leipzig University Department of Molecular Evolution and Plant Systematics & Herbarium (LZ) Johannisallee 21-23 04103 Leipzig Germany Leipzig University Department of Systematic Botany and Functional Biodiversity Research Johannisallee 21-23 04103 Leipzig Germany German Centre for Integrative Biodiversity Research (iDly) Halle-lena-Leipzig Deutscher Platz 5e 04103 Leipzig Germany

A plethora of studies investigating the origin and evolution of diverse mountain taxa has assumed a causal link between geological processes(orogenesis) and a biological response(diversification). Yet, a substantial delay(up to 30 Myr) between the start of orogenesis and diversification is often *** biologists should therefore identify alternative drivers of diversification and maintenance of biodiversity in mountain systems. Using phylogenetic, biogeographic, and diversification rate analyses,we could identify two independent processes that most likely explain the diversity of the widespread genus Allium in the Qinghaie-Tibet Plateau(QTP) region:(1) While the QTP-related taxa of the subgenus Melanocrommyum diversified in situ,(2) QTP-related taxa of other subgenera migrated into the QTP from multiple source areas. Furthermore, shifts in diversification rates within Allium could not be attributed spatially and temporally to the uplift history of the QTP region. Instead, global cooling and climate oscillations in the Quaternary were major contributors to increased speciation rates in three clades of Allium. Our study therefore adds to the growing evidence supporting the "mountain-geo-biodiversity hypothesis", which highlights the role of climate oscillations for the diversification of mountain organisms.

关键词： Allium Evolution Hengduan mountains Historical biogeography Molecular dating Qinghaie-Tibet plateau