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Friction 2014年第2期2卷 193-208页

作者： Pedro A.ROMERO Lars PASTEWKA julian von lautz Michael MOSELER Fraunhofer Institute for Mechanics of Materials IWM Wöhlerstraße 1179108 FreiburgGermany Karlsruhe Institute of Technology IAM-ZBSKaiserstraße 1276131KarlsruheGermany Freiburg Materials Research Center Stefan-Meier-Straße 2179104FreiburgGermany University of Freiburg Physics DepartmentHermann-Herder-Straße 379104 FreiburgGermany

Tetrahedral amorphous carbon coatings have the potential to significantly reduce friction and wear between sliding ***,we provide atomistic insights into the evolution of the sliding interface between naked and hydrogen-passivated ta-C sliding partners under dry and lubricated *** reactive classical atomistic simulations we show that sliding induces a sp3 to sp2 rehybridization and that the shear resistance is reduced by hydrogen-passivation and hexadecane-lubrication-despite our finding that nanoscale hexadecane layers are not always able to separate and protect ta-C counter surfaces during *** asperities deform,carbon atoms within the hexadecane lubricant bind to the ta-C sliding partners resulting in degradation of the hexadecane molecules and in increased material intermixing at the sliding *** atoms from the passivation layer and from the hexadecane chains continue to be mixed within a sp2 rich sliding interface eventually generating a tribo-layer that resembles an a-C:H type of *** separation of the sliding partners,the tribo-couple splits within the newly formed sp2 rich a-C:H mixed layer with significant material transfer across the sliding *** leaves behind a-C:H coated ta-C surfaces with dangling C bonds,linear C chains and hydrocarbon fragments.

关键词： Atomic-scale simulations DLC lubrication hexadecane passivation sliding mixed layer wear

Population dynamics of the tropical oyster Magallana bilineata(Mollusca,Bivalvia,Ostreidae)in Mengkabong Bay,Tuaran,Malaysia

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Aquaculture and Fisheries 2024年第2期9卷 295-305页

作者： Joanna W.Doinsing julian Ransangan Politeknik Sandakan Sabah Education HubBatu 10Jalan Sungai BatangSandakanSabah90000Malaysia Borneo Marine Research Institute Universiti Malaysia SabahJalan UMSKota Kinabalu88400Malaysia

Knowledge about the population dynamics within a specific spatial area is vital for the effective planning and management of important fishery *** parameters,including the asymptotic length(L∞),growth coefficient(K),mortalities(Z,F,and M),recruitment pattern,exploitation level(E),and yield per recruit(Y’/R),of the tropical oyster Magallana bilineata in Mengkabong Bay,Tuaran,Malaysia were analyzed by using the FiSAT software,using on the monthly shell length-frequency data collected from April 2019 to March 2020.A total of 435 oysters with shell lengths ranging from 3.64 to 11.16 cm were *** water temperature,salinity,dissolved oxygen,hydrogen ion concentration(pH),and chlorophyll concentration were measured at 29.0-33.7◦C,26.68-35.74 psμ,3.18-6.99 mg/L,6.57-8.29 and 1.51-98.93μg/L,*** logarithmic relationship between the length and weight of Log W=1.9055 Log L+0.1049(R2=0.5431)with exponent b of 1.9055 for combined sexes showed a negative allometric growth(bvon Bertalanffy Growth Formula(VBGF)for *** were estimated at 12.13 cm and 1.00 yr􀀀1,*** theoretical ages at length zero(t0)(0.0487)were estimated by substituting L∞and K in Pauly’s *** sizes attained by *** were 3.76,5.04,6.13,7.05,7.83,and 8.49 cm at the end of 2,4,6,8,10,and 12 months,*** calculated growth performance index(φ)for *** in Mengkabong Bay was 2.168,while the estimated lifespan was 3 *** recruitment pattern was observed year-round,with higher recruitment activities in September-October 2019 and January *** total mortality(Z)was analyzed using the length-converted

关键词： Crassostrea iredalei Length-weight relationship Growth parameters Recruitment Exploitation

Piezo1 expression in chondrocytes controls endochondral ossification and osteoarthritis development

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Bone Research 2024年第1期12卷 199-214页

作者： Laura J.Brylka Assil-Ramin Alimy Miriam E.A.Tschaffon-Müller Shan Jiang Tobias Malte Ballhause Anke Baranowsky Simon von Kroge julian Delsmann Eva Pawlus Kian Eghbalian Klaus Püschel Astrid Schoppa Melanie Haffner-Luntzer David J.Beech Frank Timo Beil Michael Amling Johannes Keller Anita Ignatius Timur A.Yorgan Tim Rolvien Thorsten Schinke Department of Osteology and Biomechanics University Medical Center Hamburg-Eppendorf20246 HamburgGermany Department of Trauma and Orthopedic Surgery University Medical Center Hamburg-Eppendorf20246 HamburgGermany Institute of Orthopedic Research and Biomechanics University Medical Center UlmBadenWürttemberg89081 UlmGermany Department Legal Medicine University Medical Center Hamburg-Eppendorf20246 HamburgGermany Leeds Institute of Cardiovascular and Metabolic Medicine School of MedicineUniversity of LeedsLS29JT LeedsUK

Piezo proteins are mechanically activated ion channels,which are required for mechanosensing functions in a variety of cell *** we and others have previously demonstrated that the expression of Piezo1 in osteoblast lineage cells is essential for boneanabolic processes,there was only suggestive evidence indicating a role of Piezo1 and/or Piezo2 in *** we addressed the question if and how chondrocyte expression of the mechanosensitive proteins Piezo1 or Piezo2 controls physiological endochondral ossification and pathological osteoarthritis(OA)*** with chondrocyte-specific inactivation of Piezo1(Piezo1^(Col2a1Cre)),but not of Piezo2,developed a near absence of trabecular bone below the chondrogenic growth plate ***,all Piezo1^(Col2a1Cre) animals displayed multiple fractures of rib bones at 7 days of age,which were located close to the growth *** skeletal growth was only mildly affected in these mice,OA pathologies were markedly less pronounced compared to littermate controls at 60 weeks of ***,when OA was induced by anterior cruciate ligament transection,only the chondrocyte inactivation of Piezo1,not of Piezo2,resulted in attenuated articular cartilage ***,osteophyte formation and maturation were also reduced in Piezo1^(Col2a1Cre) *** further observed increased Piezo1 protein abundance in cartilaginous zones of human ***,we identified Ptgs2 and Ccn2 as potentially relevant Piezo1 downstream genes in ***,our data do not only demonstrate that Piezo1 is a critical regulator of physiological and pathological endochondral ossification processes,but also suggest that Piezo1 antagonists may be established as a novel approach to limit osteophyte formation in OA.

关键词： Piezo1 markedly ossification

Generalized laws of refraction and reflection at interfaces between different photonic artificial gauge fields

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Light(Science & Applications) 2020年第1期9卷 45-55页

作者： Moshe-Ishay Cohen Christina Jörg Yaakov Lumer Yonatan Plotnik Erik H.Waller julian Schulz Georg von Freymann Mordechai Segev Physics Department Technion-Israel Institute of TechnologyHaifa 32000Israel Solid State Institute Technion-Israel Institute of TechnologyHaifa 32000Israel Physics Department and Research Center OPTIMAS TU Kaiserslautern67663 KaiserslauternGermany Department of Physics The Pennsylvania State UniversityState CollegePA 16802USA Fraunhofer Institute for Industrial Mathematics ITWM 67663 KaiserslauternGermany

Artificial gauge fields the control over the dynamics of uncharged particles by engineering the potential landscape such that the particles behave as if effective external fields are acting on *** years have witnessed a growing interest in artificial gauge fields generated either by the geometry or by time-dependent modulation,as they have been enablers of topological phenomena and synthetic dimensions in many physical settings,e.g.,photonics,cold atoms,and acoustic ***,we formulate and experimentally demonstrate the generalized laws of refraction and reflection at an interface between two regions with different artificial gauge *** use the symmetries in the system to obtain the generalized Snell law for such a gauge interface and solve for reflection and *** identify total internal reflection(TIR)and complete transmission and demonstrate the concept in *** addition,we calculate the artificial magnetic flux at the interface of two regions with different artificial gauge fields and present a method to concatenate several gauge *** an example,we propose a scheme to make a gauge imaging system-a device that can reconstruct(image)the shape of an arbitrary wavepacket launched from a certain position to a predesigned location.

关键词： gauge refraction interface

Artificial gauge field switching using orbital angular momentum modes in optical waveguides

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Light(Science & Applications) 2020年第1期9卷 577-583页

作者： Christina Jorg Gerard Queralto Mark Kremer Gerard Pelegri julian Schulz Alexander Szameit Georg von Freymann Jordi Mompartand Veronica Ahufinger Physics Department and Research Center OPTIMAS Technische Universitat Kaiserslautern67663 KaiserslauternGermany Departament de Fisica Universitat Auto’noma de BarcelonaE-08193 BellaterraSpain Institut fur Physik Universitat RostockAlbert-Einstein-StraBe 2318059 RostockGermany Department of Physics and SUPA University of StrathclydeGlasgow G40NGUK Fraunhofer Institute for Industrial Mathematics ITWM 67663 KaiserslauternGermany

The discovery of artificial gauge fields controlling the dynamics of uncharged particles that otherwise elude the influence of standard electromagnetic fields has revolutionised the field of quantum ***,developing new techniques to induce these fields is essential to boost quantum simulation of photonic ***,we experimentally demonstrate the generation of an artificial gauge field in a photonic lattice by modifying the topological charge of a light beam,overcoming the need to modify the geometry along the evolution or impose external *** particular,we show that an effective magnetic flux naturally appears when a light beam carrying orbital angular momentum is injected into a waveguide lattice with a diamond chain *** demonstrate the existence of this flux,we measure an effect that derives solely from the presence of a magnetic flux,the Aharonov-Bohm caging effect,which is a localisation phenomenon of wavepackets due to destructive ***,we prove the possibility of switching on and off artificial gauge fields just by changing the topological charge of the input state,paving the way to accessing different topological regimes in a single structure,which represents an important step forward for optical quantum simulation.

关键词： gauge momentum orbital

Accelerated tooth movement in Rsk2-deficient mice with impaired cementum formation

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International Journal of Oral Science 2020年第4期12卷 338-345页

作者： Cita Nottmeier Maximilian G.Decker Julia Luther Simon von Kroge Bärbel Kahl-Nieke Michael Amling Thorsten Schinke julian Petersen Till Koehne Department of Orthodontics University Medical Center Hamburg-EppendorfHamburgGermany Institute of Osteology and Biomechanics University Medical Center Hamburg-EppendorfHamburgGermany

Coffin–Lowry–Syndrome(CLS)is a X-linked mental retardation characterized by skeletal dysplasia and premature tooth *** and others have previously demonstrated that the ribosomal S6 kinase RSK2,mutated in CLS,is essential for bone and cementum formation;however,it remains to be established whether RSK2 plays also a role in mechanically induced bone remodeling during orthodontic tooth movement(OTM).We,therefore,performed OTM in wild-type(WT)mice and Rsk2-deficient mice using Nitinol tension springs that were fixed between the upper left molars and the *** untreated contralateral molars served as internal *** 12 days of OTM,the jaws were removed and examined by micro-computed tomography(μCT),decalcified histology,and *** analysis of the untreated teeth confirmed that the periodontal phenotype of Rsk2-deficient mice is characterized by alveolar bone loss and hypoplasia of root *** of OTM usingμCT revealed that OTM was more than two-fold faster in Rsk2-deficient mice as compared to *** also observed that OTM caused alveolar bone loss and root resorptions in WT and Rsk2-deficient ***,quantification of these orthodontic side effects revealed no differences between WT and Rsk2-deficient *** together,Rsk2 loss-of-function accelerates OTM in mice without causing more side effects.

关键词： impaired deficient movement

Nicotinamide mononucleotide:a potential effective natural compound against insulin resistance

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Signal Transduction and Targeted Therapy 2021年第9期6卷 2609-2610页

作者： julian Roos Julia Zinngrebe Pamela Fischer-Posovszky Department of Pediatrics and Adolescent Medicine Ulm University Medical CenterUlmGermany

Recently,a study published in Science by Yoshino et al.1 reported on a randomized,placebo-controlled,double-blind clinical trial to examine the effects of a 10-week nicotinamide mononucleotide(NMN)administration on human metabolism in 25 postmenopausal overweight or obese women with *** revealed positive effects of NMN on insulin sensitivity,insulin signalling,and tissue remodelling in skeletal muscle.

关键词： metabolism clinical

Assessing the microstructure and in vitro degradation behavior of Mg-xGd screw implants using μCT

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Journal of Magnesium and Alloys 2021年第6期9卷 2208-2223页

作者： Diana Krüger Berit Zeller-Plumhoff Björn Wiese Sangbong Yi Marcus Zuber D.C.Florian Wieland julian Moosmann Regine Willumeit-Römer Institute of Metallic Biomaterials Helmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany Institute of Material and Process Design Helmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany Institute for Photon Science and Synchrotron Radiation Karlsruhe Institute of TechnologyHerrmann-von-Helmholtz-Platz 1Eggenstein-Leopoldshafen 76344Germany Laboratory for Applications of Synchrotron Radiation Karlsruhe Institute of TechnologyKaiserstr.12KarlsruheGermany Institute of Materials Physics Helmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany

Biodegradable implants are taking an increasingly important role in the area of orthopedic implants with the aim to replace permanent implants for temporary bone healing *** the implant preparation process,the material’s surface and microstructure are being changed by stresses induced by *** degradable metal implants need to be fully characterized in terms of the influence of machining on the resulting microstructure and corrosion *** this study,micro-computed tomography(μCT)is used for the quantification of the degradation rate of biodegradable *** our best knowledge,for the first time quantitative measures are introduced to describe the degradation homogeneity in *** information enables a prediction in terms of implant stability during the degradation in the *** magnesium gadolinium alloys,Mg-5Gd and Mg-10 Gd(all alloy compositions are given in weight%unless otherwise stated),in the shape of M2 headless screws have been investigated for their microstructure and their degradation performance up to 56 *** the microstructure investigations particular attention was paid to the localized deformation of the alloys,due to the machining *** vitro immersion testing was performed to assess the degradation performance quantified by subsequent weight loss and volume loss(usingμCT)*** differences were observed in the degree of screw’s near surface microstructure being influenced from machining,the degradation rates of both materials appeared to be suitable for application in orthopedic *** the degradation homogeneity point of view no obvious contrast was detected between both ***,the higher degradation depth ratios between the crests and roots of Mg-5Gd ratios may indicated a less homogeneous degradation of the screws of these alloys on contract to the ones made of Mg-10Gd *** to its lower degradation rates,its more homogeneous microstructure,its weaker texture

关键词： Magnesium alloys Biodegradable implant Degradation rate Degradation homogeneity Micro-comptued tomography

Cytosolic Ca^2＋ Signals Enhance the Vacuolar Ion Conductivity of Bulging Arabidopsis Root Hair Cells

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Molecular Plant 2015年第11期8卷 1665-1674页

作者： Yi Wang julian Dindas Florian Rienmuller Melanie Krebs Rainer Waadt Karin Schumacher Wei-Hua Wu Rainer Hedrichl M. Rob G. Roelfsema Molecular Plant Physiology and Biophysics Julius-von-Sachs Institute for Biosciences Biocenter Werzburg University Julius-von-Sachs-Platz 2 97082Wurzburg Germany State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB) College of Biological Sciences China Agricultural University Beijing 100193 China Centre for Organismal Studies Developmental Biology of Plants University of Heidelberg Im Neuenheimer Feld 230 69120 Heidelberg Germany College of Science King Saud University (KSU) Riyadh Saudi Arabia

Plant cell expansion depends on the uptake of solutes across the plasma membrane and their storage within the vacuole. In contrast to the well-studied plasma membrane, little is known about the regulation of ion transport at the vacuolar membrane. We therefore established an experimental approach to study vacuolar ion transport in intact Arabidopsis root cells, with multi-barreled microelectrodes. The subcellular position of electrodes was detected by imaging current-injected fluorescent dyes. Comparison of measurements with electrodes in the cytosol and vacuole revealed an average vacuolar membrane potential of -31 inV. Voltage clamp recordings of single vacuoles resolved the activity of voltage-independent and slowly deactivating channels. In bulging root hairs that express the Ca2＋ sensor R-GECO1, rapid elevation of the cytosolic Ca^2＋ concentration was observed, after impalement with microelectrodes, or injection of the Ca^2＋ chelator BAPTA. Elevation of the cytosolic Ca^2＋ level stimulated the activity of voltage- independent channels in the vacuolar membrane. Likewise, the vacuolar ion conductance was enhanced during a sudden increase of the cytosolic Ca^2＋ level in cells injected with fluorescent Ca^2＋ indicator FURA-2. These data thus show that cytosolic Ca^2＋ signals can rapidly activate vacuolar ion channels, which may prevent rupture of the vacuolar membrane, when facing mechanical forces.

关键词： electrophysiology ion channels calcium signaling/transport fluorescence imaging Arabidopsis,vacuolar membrane

Photosensitive Material Enabling Direct Fabrication of Filigree 3D Silver Microstructures via Laser-Induced Photoreduction

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Light(Advanced Manufacturing) 2021年第2期2卷 18-23页

作者： Erik Hagen Waller julian Karst Georg von Freymann Fraunhofer Institute for Industrial Mathematics ITWM 67663 KaiserslauternGermany Physics Department and Research Center OPTIMAS Technische Universitat Kaiserslautern67663 KaiserslauternGermany ^(th)Physics Institute and Research Center SCoPE University of Stuttgart70569 StuttgartGermany

Dear Editor Laser-induced photoreduction(LPR)as a direct fabrication technique that promises to be one of the most versatile routes for fabricating highly conductive 3D metallic microstructures on-chip(e.g.,metamateri... 详细信息

关键词： Silver versatile conductive