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Neurological consequences of systemic inflammation in the premature neonate

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Neural Regeneration Research 2017年第6期12卷 890-896页

作者： Aparna Patra Hong Huang John A.bauer Peter J.Giannone OMNI Academic Service Line and Division of Neonatology Department of Pediatrics Kentucky Children's Hospital College of MedicineUniversity of Kentucky

Despite substantial progress in neonatal care over the past two decades leading to improved survival of extremely premature infants, extreme prematurity continues to be associated with long term neurodevelopmental impairments. Cerebral white matter injury is the predominant form of insult in preterm brain leading to adverse neurological consequences. Such brain injury pattern and unfavorable neurologic sequelae is commonly encountered in premature infants exposed to systemic inflammatory states such as clinical or culture proven sepsis with or without evidence of meningitis, prolonged mechanical ventilation, bronchopulmonary dysplasia, necrotizing enterocolitis and chorioamnionitis. Underlying mechanisms may include cytokine mediated processes without direct entry of pathogens into the brain, developmental differences in immune response and complex neurovascular barrier system that play a critical role in regulating the cerebral response to various systemic inflammatory insults in premature infants. Understanding of these pathologic mechanisms and clinical correlates of such injury based on serum biomarkers or brain imaging findings on magnetic resonance imaging will pave way for future research and translational therapeutic opportunities for the developing brain.

关键词： premature consequences inflammation prematurity extremely translational dysplasia sepsis necrotizing neurological

Calibration and performance of two different constitutive models for rockfill materials

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Water Science and Engineering 2016年第3期9卷 227-239页

作者： Lin-ke Li Zhan-jun Wang Si-hong Liu Erich bauer Institute of Applied Mechanics Graz University of Technology Changjiang Institute of Survey PlanningDesign and Research College of Water Conservancy and Hydropower Engineering Hohai University

In this paper, two different concepts for the constitutive modeling of the mechanical behavior of creep-sensitive rockfill materials are presented. Specifically, the performance of an extended generalized plasticity model proposed by Wang is compared with a simplified version of the hypoplastic constitutive model for weathered rockfill materials proposed by bauer. Both models can reflect the influence of the mean stress on the incremental stiffness, the peak friction angle, and the dilatancy angle. The so-called solid hardness defined for a continuum description and originally introduced by bauer is embedded in both models. Hydrochemical, thermal, and mechanical weathering are usually caused by environmental changes and are taken into account in a phenomenological description with an irreversible and time-dependent degradation of the solid hardness. A degradation of the solid hardness is usually accompanied by creep deformation of the stressed rockfill material. It is shown that appropriate modeling of creep deformation requires at least a unified description of the interaction between the time-dependent process of degradation of the solid hardness and the stress state. In this context, the solid hardness can be understood as a key parameter for describing the evolution of the state of weathering of the rockfill material. Particular attention is also paid to the necessary procedure for determining the constitutive constants of the two different constitutive models. Finally, the performance of the two different constitutive models is demonstrated by comparing the results obtained from numerical simulations with experimental data from the creep-sensitive rockfill material.

关键词： Rockfill material Creep Generalized plasticity Hypoplasticity Constitutive model

Hypoplastic constitutive modeling of wetting deformation of weathered rockfill materials

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Frontiers of Structural and Civil Engineering 2010年第1期4卷 78-91页

作者： Erich bauer Zhongzhi FU Sihong LIU Institute of Applied Mechanics Graz University of TechnologyGrazAustria Institute of Hydraulic Structures Hohai UniversityNanjing 210098China

The wetting deformation of weathered rockfill materials has been attracting growing attention from both engineers and *** importance of realistic predictions of wetting deformations for high earth and rockfill dams is a strong motivation to establish a suitable constitutive ***,the hypoplastic constitutive model by Gudehus and bauer was extended by introducing solid hardness depending on the state of *** extended model takes into account the influence of the current density,the effective stress state,the rate of deformation,and the time dependent process of degradation of the solid *** the present paper,the performance of this model is evaluated by comparing numerical simulations with experiments obtained from a water sensitive rockfill *** particular,triaxial compression paths and creep deformation under deviatoric stress states are ***,the constitutive model proposed is used to study the influence of a degradation of the solid hardness on the long term behavior of a hypothetical fill dam.

关键词： rockfill dams weathered granular materials hypoplasticity solid hardness creep stress relaxation

Influence of pressure and density on the rheological properties of rockfills

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Frontiers of Structural and Civil Engineering 2012年第1期6卷 25-34页

作者： Erich bauer Zhongzhi FU Sihong LIU Institute of Applied Mechanics Graz University of TechnologyGrazAustria Geotechnical Engineering Department Nanjing Hydraulic Research InstituteNanjing210029Ch Institute of Hydraulic Structures Hohai UniversityNanjing 210098China

Long-term deformations of rockfill dams can be related to the type of dam,the pre-compaction achieved during the construction of the dam,the history of loading events,the rheological properties of the rockfill material used,the seepage behavior caused by defects of the sealing,the interactions of the dam building with the foundation,and the hydrothermal phenomena of the stressed rockfill *** present paper investigates the theological propcrtics of coarse grained rockfill materials using a hypoplastic constitutive *** attention is paid to wetting deformation under different deviatoric loading states and *** quantify the state of weathering a so-called“solid hardness”is used in the sense of a continuum *** is shown that an appropriate modeling of wetting deformations requires a unified description of the interaction at least between the state of weathering,the stress state,the density and the rate of *** results obtained from the numerical simulations are compared with available experimental data for a rockfill material used in Xiaolangdi earth dam.

关键词： rockfills solid hardness wetting deformation hypoplasticity creep

＂Fluidic Diode＂ for Passive Unidirectional Liquid Transport Bioinspired by the Spermathecae of Fleas

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Journal of Bionic Engineering 2018年第1期15卷 42-56页

作者： Gerda Buchberger Alexander Kogler Agnes Weth Richard Baumgartner Philipp Comanns Siegfried bauer Werner Baumgartner Institute of Biomedical Mechatronics Johannes Kepler University Linz Altenberger Str. 69 A-4040 Linz Austria institute of Experimental Physics Department of Soft Matter Physics Johannes Kepler University Linz Altenberger Str. 69 A-4040 Linz Austria Institute of Biology II RWTH Aachen University Worringerweg 3 D-52074 Aachen Germany

We present a device for passive unidirectional liquid transport. The capillary channels used are bioinspired by the shape of the spermathecae （receptaculum seminis） of rabbit fleas （Spilopsyllus cuniculi） and rat fleas （Xenopsytla cheopis）. The spermatheca is an organ of female fleas that stores sperm until suitable conditions to lay eggs are found. We translated and multiplied the natural form and function of a spermatheca to create a continuous capillary system from which we designed our microfluidic device based directly on the model from nature. Applying the Young-Laplace equation, we derived a theoretical description of local liquid transport, which enables model-guided design. We arranged the bioinspired capillaries in parallel and engraved them in poly（methyl methacrylate）（PMMA） plates by CO2 laser ablation. The fabricated structures transport soapy water passively （i.e., without external energy input） in the forward direction at velocities of about 1 mm＇s i while halting the liquid fronts completely in the backward direction. The bio- inspired capillary channels are capable of unidirectional liquid transport against gravity. Distance and velocity measurements prove the feasibility of the concept. Unidirectional passive liquid transport might be advantageous in technical surfaces for liquid man- agement, for instance, in biomedical microfluidics, lab-on-chip, lubrication, electronics cooling and in micro-analysis devices.

关键词： liquid diode wetting passive unidirectional liquid transport capillary bioinspired

Damage visualization and deformation measurement in glass laminates during projectile penetration

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Defence Technology（防务技术） 2014年第2期10卷 226-238页

作者： Elmar STRASSBURGER Steffen bauer Gregor POPKO Fraunhofer Institute for High-Speed Dynamics Ernst-Mach-Institute(EMI)Am Christianswuhr 2

Transparent armor consists of glass-polymer laminates in most *** formation and propagation of damage in the different glass layers has a strong influence on the ballistic resistance of such *** order to clarify(he course of events during projectile penetration,an experimental technique was developed,which allows visualizing the onset and propagation of damage in each single layer of the laminate.A telecentric objective lens was used together with a microsecond video camera that allows recording 100 frames at a maximum rate of 1 MHz in a backlit photography *** this technique,the damage evolution could be visualized in glass laminates consisting of four glass layers with lateral dimensions 500 mm x 500 *** evolution was recorded during penetration of 7.62 mm AP projectiles with tungsten carbide core and a total mass of 1 1.1 g in the impact velocity range from 800 to 880 m/*** order to measure the deformation of single glass plates within the laminates,a piece of reflecting tape was attached to the corresponding glass plate,and photonic Doppler velocimetry(PDV) was *** the photonic Doppler *** infrared laser is used to illuminate an object to be measured and the Doppler-shifted light is superimposed to a reference light beam at the *** simultaneous visualization and PDV measurement of the glass deformation allow determining the deformation at the time of the onset of *** analysis of the experimental data was supported by numerical simulations,using the AUTODYN commercial hydro-code.

关键词：变形测量玻璃层可视化弹丸穿透多普勒测速仪层板伤害

Structure-Function Analysis of Arabidopsis thaliana Histidine Kinase AHK5 Bound to Its Cognate Phosphotransfer Protein AHP1

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Molecular Plant 2013年第3期6卷 959-970页

作者： Johannes bauer Kerstin Reiss Manikandan Veerabagu Michael Heunemann Klaus Harter Thilo Stehle Interfaculty Institute of Biochemistry University of Tubingen D-72076 Tubingen Germany Center for Plant Molecular Biology University of TObingen D-72076 T0bingen Germany Department of Pediatrics Vanderbilt University School of Medicine Nashville TN 37232 USA

The multi-step phosphorelay （MSP） system defines a key signal transduction pathway in plants and many eukaryotes. In this system, external stimuli first lead to the activation of a histidine kinase, followed by transfer of a phosphoryl group from the receiver domain of the kinase （HKRD） to downstream, cytosolic phosphotransfer proteins （HPs）. In order to establish the determinants of specificity for this signaling relay system, we have solved the first crystal structure of a plant HKRD, AHK5RD, in complex with one of its cognate HPs, AHP1. AHP1 binds AHK5RD via a prominent hydrogen bond docking ridge and a hydrophobic patch. These features are conserved among all AHP proteins, but differ significantly from other structurally characterized prokaryotic and eukaryotic HPs. Surface plasmon resonance experiments show that AHK5RD binds to AHP1-3 with similar, micromolar affinity, consistent with the transient nature of this signaling complex. Our correlation of structural and functional data provide the first insight, at the atomic level as well as with quantitative affinity data, into the molecular recognition events governing the MSP in plants.

关键词： multi-step phosphorelay phosphotransfer protein plant signaling sensor histidine kinase two-component system.

Anisotropic deformation for local shape control

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Computational Visual Media 2017年第4期3卷 305-313页

作者： Matteo Colaianni Christian Siegl Jochen Süвmuth Frank bauer Günther Greiner Computer Graphics Group University Erlangen-Nuremberg Adidas AG

We present a novel approach to mesh deformation that enables simple context sensitive manipulation of 3 D geometry. The method is based on locally anisotropic transformations and is extended to global control directions. This allows intuitive directional modeling within an easy to implement framework. The proposed method complements current sculpting paradigms by providing further possibilities for intuitive surface-based editing without the need for additional host geometries. We show the anisotropic deformation to be seamlessly transferable to free boundary parameterization methods, which allows us to solve the hard problem of flattening compression garments in the domain of apparel design.

关键词： anisotropy modeling as-rigid-aspossible(ARAP) deformation parameterization

Ultrafast spectroscopy of semiconductor saturable absorber mirror

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Chinese Optics Letters 2010年第7期8卷 676-679页

作者：张靓 Dominik bauer Farina Knig Thomas Dekorsy 张喜和陈亚符 Department of Physics Changchun University of Science and Technology Department of Physics and Center of Applied Photonics University of Konstanz

Ultrafast spectroscopy of semiconductor saturable absorber mirror （SESAM） is measured using a femtosec- ond pump-probe experiment. This allows dynamic responses of SESAM in the cavity to be concluded by ultrafast spectroscopy. Change in reflection is measured as a function of pump-probe delay for different pump excitation fluences. Change of nonlinear reflection of SESAM is measured as a function of incident light energy density. When the excitation fluence increases, nonlinear change in ultrafast spectroscopy of SESAM becomes increasingly significant. When SESAM is pumped by an ultrahigh excitation fluence, the energy density of which is approximately 1400 μJ/cm2, two-photon absorption can be observed visibly in its ultrafast spectroscopy.

关键词： Dynamic response Light reflection Mirrors Probes Pumps Two photon processes