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B3 0749+460A: A New Repeat “Changing-look” Active Galactic Nucleus Associated with X-Ray Spectral Slope Variations

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Research in Astronomy and Astrophysics 2022年第1期22卷 114-125页

作者： J.Wang W.K.Zheng D.W.Xu T.G.brink A.V.Filippenko C.Gao S.S.Sun J.Y.Wei Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Department of Astronomy University of CaliforniaBerkeleyCA 94720-3411USA School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Miller Institute for Basic Research in Science University of CaliforniaBerkeleyCA 94720USA

Here we report an identification of B3 0749+460 A as a new double-peaked local "changing-look" active galactic nucleus(CL-AGN) in terms of our multi-epoch spectroscopic analysis. By comparing our new spectra taken in 2021 with the ones taken by the Sloan Digital Sky Survey in 2004, BOSS in 2013 and Ma NGA in 2016, we reveal type transitions of Seyfert(Sy) 1.9 → Sy1.8 → Sy1.9. In the transitions, the classical broad Hα emission fades away after 2013 and disappears in our 2021 spectrum, although the absence of broad Hβ can be traced back to at least 2016. A follow-up observation in X-rays by the Swift/XRT reveals that(1) the X-ray emission level gradually decreased since 2005;and(2)the X-ray spectrum is soft in the optical "turn-off" state and hard in the "turn-on" state. We argue that the disappearance of the classical broad Hα emission can be likely explained by the disk-wind broad-line-region model, in which the CL phenomenon is sensitive to luminosity in individual AGNs.

关键词： galaxies:Seyfert galaxies:nuclei (galaxies:)quasars:emission lines (galaxies:)quasars:individual(B30749+460A) X-rays:galaxies

Are Off-Field Activities an Underestimated Risk for Hamstring Injuries in Dutch Male Amateur Soccer Players?An Exploratory Analysis of a Prospective Cohort Study

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Journal of Science in Sport and Exercise 2022年第1期4卷 28-36页

作者： Jur J.Brauers Peter Alexander van de Hoef Maarten van Smeden Frank J.G.Backx Michel S.brink Department of Rehabilitation Physical Therapy Science and SportsUtrecht UniversityUniversity Medical Center UtrechtBrain CenterUtrechtThe Netherlands Julius Center for Health Sciences and Primary Care University Medical Center UtrechtUtrecht UniversityUtrechtThe Netherlands Center for Human Movement Sciences University of GroningenUniversity Medical Center GroningenGroningenThe Netherlands

Purpose The purpose of this study was to explore what extent male amateur soccer players participate in off-field activities and whether these off-field activities are associated with the development of hamstring *** Amateur soccer players(n=399)from first-class selection teams(n=32)filled out a baseline screening question-naire concerning off-field activities(i.e.,work and study type and hours,traveling time,sleep,energy costs,and time spent on other activities)and their history of hamstring injury as a part of a cluster-randomized controlled *** one competition,the players reported weekly their hamstring injuries,which were verified by medical/technical ***-able Firth corrected logistic regression models were used to explore associations between off-field activities and hamstring *** Sixty-five hamstring injuries were *** injury was significantly associated with hamstring injuries(OR ranging from 1.94[95%CI 1.45-2.61]to 2.02[95%CI 1.49-2.73]),but off-field activities were *** Although amateur soccer players spent a relatively large amount of time on off-field activities,we did not find off-field activities measured at baseline to be associated with hamstring injuries in the subsequent competitive soccer *** contrast,previous hamstring injury was found to be strongly associated with(recurrent)hamstring injuries.

关键词： Risk factors Activities of daily living Psychosocial factors Football Athletic injuries

Adhesive wear mechanisms uncovered by atomistic simulations

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Friction 2018年第3期6卷 245-259页

作者： Jean-Fran?ois MOLINARI Ramin AGHABABAEI Tobias brink Lucas FRéROT Enrico MILANESE Civil Engineering Department Materials Science Department école Polytechnique Fédérale de Lausanne Department of Engineering-Mechanical Engineering Aarhus Universitet

In this review, we discuss our recent advances in modeling adhesive wear mechanisms using coarse-grained atomistic simulations. In particular, we present how a model pair potential reveals the transition from ductile shearing of an asperity to the formation of a debris particle. This transition occurs at a critical junction size, which determines the particle size at its birth. Atomistic simulations also reveal that for nearby asperities, crack shielding mechanisms result in a wear volume proportional to an effective area larger than the real contact area. As the density of microcontacts increases with load, we propose this crack shielding mechanism as a key to understand the transition from mild to severe wear. We conclude with open questions and a road map to incorporate these findings in mesoscale continuum models. Because these mesoscale models allow an accurate statistical representation of rough surfaces, they provide a simple means to interpret classical phenomenological wear models and wear coefficients from physics-based principles.

关键词：粗糙粒度粘合剂摩擦学理论研究

Bacterial communities associated with natural and commercially grown rooibos (Aspalathus linearis)

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Pedosphere 2020年第6期30卷 778-790页

作者： Casparus J.brink Anneke POSTMA Etienne SLABBERT Ferdinand POSTMA A.Muthama MUASYA Karin JACOBS Department of Microbiology University of StellenboschPrivate Bag X1Stellenbosch 7600South Africa Central Analytical Facility University of StellenboschPrivate Bag X1Stellenbosch 7602South Africa Department of Biological Sciences University of Cape TownPrivate Bag X3Rondebosch 7701South Africa

Aspalathus linearis is a commercially important plant species endemic to the Cape Floristic Region of South Africa and is used to produce a herbal tea known as rooibos *** interactions between *** and soil bacteria play an important role in the survival of Aspalathus plants in the highly nutrient-poor,acidic fynbos *** aim of this study was to characterize and compare rhizosphere and bulk soil bacterial communities associated with natural and commercially grown ***,as well as the effect of seasonal changes on these *** communities were characterized using high throughput amplicon sequencing,and their correlations with soil chemical properties were *** N-fixing bacterial community was characterized using terminal restriction fragment length polymorphism and real time quantitative polymerase chain ***,Proteobacteria,and Acidobacteria were the most dominant bacterial phyla detected in this *** similar bacterial communities were associated with natural and commercially grown *** differences in the bacterial community were observed between rhizosphere and bulk soils collected in the dry season,while no significant differences were detected in the wet *** study provides insights into bacterial community structure and potential factors shaping bacterial community structure with commercially important ***.

关键词： bulk soil fynbos N-fixing bacterial community operational taxonomic unit rhizosphere soil 16S rRNA sequencing

Near-Real-Time Analysis of Publicly Communicated Disaster Response Information

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International Journal of Disaster Risk Science 2014年第3期5卷 165-175页

作者： Trevor Girard Friedemann Wenzel Bijan Khazai Tina Kunz-Plapp James E.Daniell Susan A.brink Center for Disaster Management and Risk Reduction Technology Karlsruhe Institute of Technology76187 KarlsruheGermany

Analysis of a disaster event can identify strengths and weaknesses of the response implemented by the disaster management system;however, analysis does not typically occur until after the response phase is *** result is that knowledge gained can only benefit future responses rather than the response under investigation. This article argues that there is an opportunity to conduct analysis while the response is operational due to the increasing availability of information within hours and days of a disaster event. Hence, this article introduces a methodology for analyzing publicly communicated disaster response information in near-real-time. A classification scheme for the disaster information needs of the public has been developed to facilitate analysis and has led to the establishment of best observed practice standards for content and timeliness. By comparing the information shared with the public within days of a disaster to these standards,information gaps are revealed that can be investigated further. The result is identification of potential deficiencies in communicating critical disaster response information to the public at a time when they can still be corrected.

关键词： Disaster response information Forensic disaster analysis Near-real-time analysis Post disaster evaluation

Comprehensive scan for nonmagnetic Weyl semimetals with nonlinear optical response

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npj Computational Materials 2020年第1期6卷 1398-1404页

作者： Qiunan Xu Yang Zhang Klaus Koepernik Wujun Shi Jeroen van den brink Claudia Felser Yan Sun Max Planck Institute for Chemical Physics of Solids 01187 DresdenGermany Leibniz Institute for Solid State and Materials Research 01069 DresdenGermany School of Physical Science and Technology ShanghaiTech UniversityShanghai 200031China Center for Nanoscale Systems Faculty of Arts and SciencesHarvard University11 Oxford StreetLISE 308CambridgeMA 02138USA

First-principles calculations have recently been used to develop comprehensive databases of nonmagnetic topological materials that are protected by time-reversal or crystalline ***,owing to the low symmetry requirement of Weyl points,a symmetry-based approach to identifying topological states cannot be applied to Weyl semimetals(WSMs).To date,WSMs with Weyl points in arbitrary positions are absent from the well-known databases.

关键词： symmetry topological metals

Thermo-Mechanical Influence on the Internal Friction of a 51CrV4 Shaft

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Chinese Physics Letters 2012年第11期29卷 131-135页

作者： J.Göken I.S.Golovin T.S.Andrianova K.Steinhoff H.brink Faculty of Maritime Studies University of Applied Sciences Emden-LeerBergmannstrasse 3626789 LeerGermany Department of Physical Metallurgy of Non-Ferrous Metals National Research Technological University'MISIS'119049MoscowLeninskiy Prospekt 4Russia Chair of Metal Forming Technology University of KasselKurt-Wolters-Str.334125 KasselGermany

The influence of simultaneously applied mechanical and thermal treatment is used for producing a geometrically complex shaft from 51CrV4 steel resulting in widely differing formations of ***'properties such as internal friction(IF),hardness and electrical resistivity are affected by this change of microstructure *** Snoek–Koster peak is identified and analyzed in the actual steel structure.

关键词： 51CrV4 structure steel

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Xin Nian Hao!

Voice of Friendship 2015年第2期 40-41页

作者： Julie brink

Happy New Year–Xin nian hao!This is heard again and again in the Concert Hall in *** Chinese and Danes greet one another,and all are here to celebrate the Chinese New *** all started in humble surroundings in *** was in a shopping mall in the outskirts of *** spite of lack of space and facilities the celebration was a relative success。

关键词： facilities again spite celebrate surroundings Happ

Phylogeny of the industrial relevant,thermophilic genera Myceliophthora and Corynascus

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Fungal Diversity 2012年第1期52卷 197-207页

作者： Joost van den brink Robert A.Samson Ferry Hagen Teun Boekhout Ronald P.de Vries CBS-KNAW Fungal Biodiversity Centre P.O.Box 851673508 AD UtrechtThe Netherlands

Species of the genus Myceliophthora and its teleomorph Corynascus have attracted increasing interest due to their potential to produce thermostable *** study re-assessed the phylogenetic relationship of 49 isolates of nine species belonging to Myceliophthora and *** species,***,was shown not to belong to the genus Myceliophthora and should be placed in the genus *** other species belonged to two phylogenetic clusters:mesophilic fungi with the type species *** and ***,and thermophilic fungi with ***,*** and *** phylogenetic data provides no clear separation of the two genera Corynascus and *** avoid confusion in future taxonomic studies,it is proposed that all existing Corynascus species be renamed to Myceliophthora,which is the old name and the one more frequently ***,this study identified two groups within the isolates listed as *** and assigned one group(five isolates)to *** based on AFLP analysis and mating *** study provides new insights into the genetic differences within the genus Myceliophthora and will therefore be essential for the interpretation of future genomic and physiological studies of these species.

关键词： Myceliophthora Corynascus Thermophiles M.heterothallica M.thermophila.Thermophilic fungi Multigene phylogeny AFLP analysis Mating behavior