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enslaved Phase-Separation Fronts and Liesegang Pattern Formation

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Communications in Computational Physics 2011年第5期9卷 1081-1093页

作者： e.M.Foard A.j.Wagner Department of Physics North Dakota State UniversityFargoND 58105USA

We show that an enslaved phase-separation front moving with diffusive speeds U=C/√T can leave alternating domains of increasing size in their *** find the size and spacing of these domains is identical to Liesegang *** equal composition of the components we are able to predict the exact form of the pattern *** our knowledge this is the first fully analytical derivation of the Liesegang *** also show that there is a critical value for C below which only two domains are *** analytical predictions are verified by numerical simulations using a lattice Boltzmann method.

关键词： Liesegang phase separation front reaction diffusion pattern formation lattice Boltzmann Matalon-Packter

Benchmark for scale-resolving simulation with curved walls: the Taylor Couette flow

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Advances in Aerodynamics 2021年第1期3卷 281-298页

作者： Z.j.Wang e.jourdan Department of Aerospace engineering University of KansasLawrenceKS 66045USA

Flow between rotating concentric cylinders,or the Taylor Couette flow,has been studied extensively because of its rich physics,ranging from axisymmetric steady laminar flow,to fully developed turbulent *** the present study,we advocate the use of this problem as a benchmark case for scale-resolving simulation,such as large eddy simulation(LeS)and direct numerical simulation(DNS).The problem is attractive because of its simple geometry,simple boundary conditions,and complex physics involving wall-shear induced and centrifugal *** the wellknown fully developed channel flow,this problem has a curved wall boundary,and it is unnecessary to add a source term to the governing equations to sustain the fully developed turbulent flow.A p-refinement study for Re=4000 is performed first to establish DNS data,including the time history of enstrophy,which can be used as an accuracy and resolution indicator to evaluate numerical methods,and is orders of magnitude faster than using the mean flow quantities and Reynolds stresses to evaluate solution ***,an hp-refinement study is performed to establish the relative accuracy and efficiency of high-order schemes of various accuracy.

关键词： Large eddy simulation Direct numerical simulation High-order methods Navier-Stokes Taylor Couette flow

A vestigial pathway for sex differences in immune regulation

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Cellular & Molecular Immunology 2017年第7期14卷 578-580页

作者： Yun Liang j Michelle Kahlenberg johann e Gudjonsson Department of Dermatology University of MichiganAnn ArborMI 48109USA Division of Rheumatology Department of Internal MedicineUniversity of MichiganAnn ArborMI 48109USA

Autoimmune diseases have a strikingly higher prevalence in women compared to men,with approximately 80%of individuals affected with autoimmune diseases being *** nature of this sex-bias has remained unclear,but sex hormones have previously been implicated as the leading underlying *** this research highlight,we discuss a recently identified transcription factor。

关键词： diseases autoimmune prevalence

Measurement and analysis technologies for magnetic pulse welding： established methods and new strategies

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Advances in Manufacturing 2016年第4期4卷 322-339页

作者： j. Bellmann j. Lueg-Althoff S. Schulze S. Gies e. Beyer A. e. Tekkaya Institute of Manufacturing Science and engineering TUDresden 01062 Dresden Germany Fraunhofer Institute for Material and Beam Technology Winterbergstrasse 28 01277 Dresden Germany Institute of Forming Technology and LightweightConstruction TU Dortmund Baroper Strasse 30344227 Dortmund Germany

Magnetic pulse welding （MPW） is a fast and clean joining technique that offers the possibility to weld dissimilar metals, e.g., aluminum and steel. The high-speed collision of the joining partners is used to generate strong atomic bonded areas. Critical brittle intermetallic phases can be avoided due to the absence of external heat. These features attract the notice of industries performing large scale productions of dissimilar metal joints, like automo- tive and plant engineering. The most important issue is to guarantee a proper weld quality. Numerical simulations are often used to predict the welding result a priori. Nevertheless, experiments and the measurement of process parameters are needed for the validation of these data. Sensors nearby the joining zone are exposed to high pressures and intense magnetic fields which hinder the evaluation of the electrical output signals. In this paper, existing analysis tools for process development and quality assurance in MPW are reviewed. New methods for the process monitoring and weld characterization during and after MPW are introduced, which help to overcome the mentioned drawbacks of established technologies. These methods are based on optical and mechanical measuring technologies taking advantage of the hypervelocity impact flash, the impact pressure and the deformation necessary for the weld formation.

关键词： Magnetic pulse welding (MPW) Processmonitoring Collision conditions Dissimilar metaljoining Materials testing

New multi-phonon gamma vibrational bands in A～110 neutron-rich nuclei

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Science China(Physics,Mechanics & Astronomy) 2011年第S1期54卷 44-48页

作者： HAMILTON j H RAMAYYA A V RASMUSSeN j O HWANG j K YeOH e Y Department of Physics Vanderbilt University Nashville TN 37235 USA Lawrence Berkeley National Laboratory Berkeley CA 94720 USA Department of Physics Tsinghua University Beijing 100084 China

The high spin states of neutron-rich 103Nb, 107Tc and 109Tc nuclei in A^110 region have been investigated by measuring prompt γ-γ-γ coincident measurements populated with the spontaneous fission of 252Cf with the Gammasphere detector array. In 103Nb, one-phonon K = 9/2 and two-phonon K = 13/2 γ-vibrational bands have been identified. In 107Tc and 109Tc, one-phonon K = 11/2 and two-phonon K = 15/2 γ-vibrational bands, in which the zero-phonon bands are based on K=7/2 excited states, have also been identified. The two-phonon bands are first observed in odd-Z nuclei. The characteristics for these band structures have been discussed.

关键词： high spin states neutron-rich nucleus γ-vibrational bands

In vitro evaluation of 3D printed polycaprolactone scaffolds with angle-ply architecture for annulus fibrosus tissue engineering

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Regenerative Biomaterials 2019年第3期6卷 175-184页

作者： T.R.Christiani e.Baroncini j.Stanzione A.j.Vernengo Department of Biomedical engineering Department of Chemical engineering Rowan University201 Mullica Hill RoadGlassboroNJ 08028USA

Tissue engineering of the annulus fibrosus(AF)is currently being investigated as a treatment for intervertebral disc degeneration,a condition frequently associated with low back *** objective of this work was to use 3D printing to generate a novel scaffold for AF repair that mimics the structural and biomechanical properties of the native ***-layer scaffolds were fabricated by depositing polycaprolactone struts in opposing angular orientations,replicating the angle-ply arrangement of the native AF *** were printed with varied strut diameter and *** constructs were characterized morphologically and by static and dynamic mechanical *** surfaces were etched with unidirectional grooves and the influence on bovine AF cell metabolic activity,alignment,morphology and protein expression was studied in ***,the axial compressive and circumferential tensile properties of the scaffolds were found to be in a similar range to the native AF *** microscopy images indicated that cells were able to attach and spread on the smooth polycaprolactone scaffolds,but the surface texture induced cellular alignment and ***,immunofluorescence analysis demonstrated the aligned deposition of collagen type I,aggrecan and the AF-specific protein marker tenomodulin on the etched ***,results demonstrated the potential for using the scaffolds as a template for AF regeneration.

关键词： surface modification scaffolds materials structure 3D printing

Salic Horizons in Soils of the USA

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Pedosphere 2013年第5期23卷 600-608页

作者： j. G. BOCKHeIM A. e. HARTeMINK Department of Soil Science University of Wisconsin

The taxonomic hierarchy and nationwide distribution of soils with a salic horizon were studied using the USA Natural Resources Conservation Service Soil Survey Geographic （SSURGO） Database to provide a more holistic view of the role of soil-forming factors in pedogenesis than from isolated case studies. Soils with a salic horizon occupied an area of 11 000 km2, i.e., 0.1% of land area in the contiguous USA. These soils occur narrowly in three great groups （Aquisalids, Haplosalids and Halaquepts）, 11 subgroups, and 97 soil series. Soils with a salic horizon commonly had a mesic （50% of soil series） or thermic （19%） soil-temperature class, an aquic （89%） soil-moisture class, a mixed mineral class （79%）, a calcareous （52%） reaction class, a superaztive （59%） cation exchange activity class, and a fine （24% of soil series）, fine-loamy （24% of soil series）, or fine-silty （19% of soil series） particle-size class. Soils with a salic horizon were concentrated in the Basin and Range Province of western USA. The key pedogenic processes leading to the development of salic horizons were salinization, gleization, and calcification, with some evidence for argilluviation and silicification.

关键词： saline soils soil classification solonchak

Lysozyme as an alternative to growth promoting antibiotics in swine production

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journal of Animal Science and Biotechnology 2016年第1期7卷 34-40页

作者： W. T. Oliver j.e.Wells USDA ARS U.S. Meat Animal Research Center P. O. Box 166 Clay Center NE68933-0166 USA

Lysozyme is a naturally occurring enzyme found in bodily secretions such as tears, saliva, and milk. It functions as an antimicrobial agent by cleaving the peptidoglycan component of bacterial cell walls, which leads to cell death. Antibiotics are also antimicrobials and have been fed at subtherapeutic levels to swine as growth promoters. These compounds benefit swine producers by minimizing production losses by increasing feed efficiency and decreasing susceptibility to bacterial infection and disease. This manuscript reviews the knowledge of the effects of lysozyme, as compared to traditional subtherapeutic antibiotics in swine feed, on pig performance and health. It is clear from decades of studies that antibiotic use in feeds increases pig performance, particularly in the nursery. Similarly, lysozyme, as a feed additive, increases growth and feed efficiency. While the mechanism by which antibiotics and lysozyme improve performance is not clearly understood, both of these feed additives improve gastrointestinal health, improve the metabolic profile, and alter the gastrointestinal bacteria ecology of swine. Therefore, lysozyme is a suitable alternative to growth-promoting subtherapeutic antibiotic use in swine feed.

关键词： Antibiotics Gastrointestinal Lysozyme Microbiota Review Swine

Cell Wall Microstructure Analysis Implicates Hemicellulose Polysaccharides in Cell Adhesion in Tomato Fruit Pericarp Parenchyma

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Molecular Plant 2009年第5期2卷 910-921页

作者： jose j. Ordaz-Ortiz Susan e. Marcus j. Paul Knox Centre for Plant Sciences Faculty of Biological Sciences University of Leeds Leeds LS2 9JT United Kingdom

Methods developed to isolate intact cells from both unripe and ripe tomato fruit pericarp parenchyma have allowed the cell biological analysis of polysaccharide epitopes at the surface of separated cells. The LM7 pectic homogalacturonan epitope is a marker of the junctions of adhesion planes and intercellular spaces in parenchyma systems. The LM7 epitope persistently marked the former edge of adhesion planes at the surface of cells separated from unripe and ripened tomato fruit and also from fruits with the Cnr mutation. The LM 11 xylan epitope was associated, in sections, with cell walls lining intercellular space but the epitope was not detected at the surface of isolated cells, being lost during cell isolation. The LM15 xyloglucan epitope was present at the surface of cells isolated from unripe fruit in a pattern reflecting the former edge of cell adhesion planes/intercellular space but with gaps and apparent breaks. An equivalent pattern of LM15 epitope occurrence was revealed at the surface of cells isolated by pectate lyase action but was not present in cells isolated from ripe fruit or from Cnr fruit. In contrast to wild-type cells, the LM5 galactan and LM21 mannan epitopes occurred predominantly in positions reflecting intercellular space in Cnr, suggesting a concerted alteration in cell wall microstructure in response to this mutation. Galactanase and mannanase, along with pectic homogalacturonan-degrading enzymes, were capable of releasing cells from unripe fruit parenchyma. These observations indicate that hemicellulose polymers are present in architectural contexts reflecting cell adhesion and that several cell wall polysaccharide classes are likely to contribute to cell adhesion/cell separation in tomato fruit pericarp parenchyma.

关键词： Cell walls fruit development tomato cell adhesion cell separation polysaccharide.