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Computer animations of color markings revealthe function of visual threat signals inNeolamprologus pulcher

Current Zoology 2017年第1期63卷 45-54页

作者： Valentina BALZARINI Michael TABORSKY Fabienne VILLA joachim G. FROMMEN Institute of Ecology and Evolution Behavioral Ecology Division University of Bern Wohlenstrasse 50a 3032Hinterkappelen Switzerland

Visual signals, including changes in coloration and color patterns, are frequently used by animalsto convey information. During contests, body coloration and its changes can be used to assess anopponent＇s state or motivation. Communication of aggressive propensity is particularly importantin group-living animals with a stable dominance hierarchy, as the outcome of aggressive inter-actions determines the social rank of group members. Neolamprologus pulcher is a cooperativelybreeding cichlid showing frequent within-group aggression. Both sexes exhibit two vertical blackstripes on the operculum that vary naturally in shape and darkness. During frontal threat displaysthese patterns are actively exposed to the opponent, suggesting a signaling function. To investi-gate the role of operculum stripes during contests we manipulated their darkness in computeranimated pictures of the fish. We recorded the responses in behavior and stripe darkness of testsubjects to which these animated pictures were presented. Individuals with initially darker stripeswere more aggressive against the animations and showed more operculum threat *** stripes of test subjects became darker after exposure to an animation exhibiting a paleoperculum than after exposure to a dark operculum animation, highlighting the role of the dark-ness of this color pattern in opponent assessment. We conclude that （i） the black stripes on theoperculum of N. pulcherare a reliable signal of aggression and dominance, （ii） these markings playan important role in opponent assessment, and （iii） 2D computer animations are well suited to elicitbiologically meaningful short-term aggressive responses in this widely used model system ofsocial evolution.

关键词： aggression, agonistic behavior, animated pictures, cichlid fish, communication, cooperation, social, threat display.

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Identification and characterization of a novel bipartite nuclear localization signal in the hepatitis B virus polymerase

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World Journal of Gastroenterology 2013年第44期19卷 8000-8010页

作者： joachim Lupberger Stephanie Schaedler Alexander Peiran Eberhard Hildt Department of Medicine Ⅱ University of Freiburg D-79106 Freiburg Germany Inserm U748 Strasbourg France Division of Virology University Goettingen37073 Goettingen Germany Division of Virology Paul-Ehrlich-InstituteD-63325 Langen Germany

AIM: To characterize the nuclear import of hepatitis B virus (HBV) polymerase (P) and its relevance for the viral life cycle.METHODS: Sequence analysis was performed to predict functional motives within P. Phosphorylation of P was analyzed by in vitro phosphorylation. Phosphorylation site and nuclear localization signal (NLS) were destroyed by site directed mutagenesis. Functionality of the identified NLS was analyzed by confocal fluorescence microscopy and characterizing the karyopherin binding. Relevance of the structural motives for viral life cycle was studied by infection of primary Tupaia hepatocytes with HBV.RESULTS: We identified by sequence alignment and functional experiments a conserved bipartite NLS containing a casein kinase II (CKII) phosphorylation site located within the terminal protein domain (TP) of the HBV polymerase. Inhibition of CKII impairs the functionality of this NLS and thereby prevents the nuclear import of the polymerase. Binding of the import factor karyopherin-α2 to the polymerase depends on its CKII-mediated phosphorylation of the bipartite NLS. In HBV-infected primary Tupaia hepatocytes CKII inhibition in the early phase (post entry phase) of the infection process prevents the establishment of the infection.CONCLUSION: Based on these data it is suggested that during HBV infection the final import of the genome complex into the nucleus is mediated by a novel bipartite NLS localized in the TP domain of HBV polymerase.

关键词： Hepatitis B virus Nuclear localization signal Casein kinase II Trafficking Replication

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From micro-scale to technical dimension—Challenges in the simulation ofdense gas-particle flows

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Particuology 2009年第4期7卷 231-232页

作者： joachim Werther Ernst-Ulrich Hartge Jinghai Li Wei Ge Institute of Solids Process Engineering and Particle Technology Hamburg University of Technology Hamburg Germany State Key Laboratory of Multi-phase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing China

Supported by the Sino-German Center for Research Promotion, an organization jointly founded by the National Natural Science Foundation of China （NSFC） and the German Research Foundation （DFG）, a joint Sino-German workshop on particle fluid systems was held for the fourth time on May 19-20, 2008 in Hamburg. Previous workshops were held on August 30-31, 1999 in Ham- burg,

关键词： From micro-scale to technical dimension EMMS Challenges in the simulation ofdense gas-particle flows

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REMARKS ON SINO-GERMAN WORKSHOP ON CHEMICAL AND PHYSICAL INTERACTIONS BETWEEN PARTICLES AND FLUIDS

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Particuology 2005年第Z1期 143-144页

作者： joachim Werther Department of Chemical Engineering I Technical University Hamburg-Harburg Hamburg 21071 Germany

This paper presents some remarks on the perspectives of process engineering in the 21st century extracted from the discussion at the workshop. It is considered that the field will be upgraded by introducing knowledge in other fields, extended to even more applications by generalizing the relevant methods, and unified to, at least covered by, the complexity science. Transdisciplinarity is necessary to cope with this challenge.

关键词： particle-fluid interaction complexity process engineering multi-scale multi-phase multi-level

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The feasibility of coating by cooling crystallization on ibuprofen naked tablets

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Frontiers of Chemical Science and Engineering 2017年第2期11卷 211-219页

作者： Fatima Mameri Ouahiba Koutchoukali Mohamed Bouhelassa Anne Hartwig Leila Nemdili joachim Ulrich University Constantine 3 Engineering Faculty of Pharmaceutical Processes 25000 Constantine Algeria Martin Luther University Halle-Wittenberg Center of Engineering Science Thermal Process Engineering D-06099 Halle Germany

Sugar spray coating is a frequently used process in the pharmaceutical industry. However, this process presents the disadvantage to form an amorphous coating around the active ingredient. A crystalline coating formed on the surface of a tablet is highly desirable. Recently, a new process of coating by cooling crystallization has been developed and applied on bisacodyl pastilles obtained by melt crystallization. In this work, we investigated the feasibility of coating by cooling crystallization on ibuprofen ＂naked tablets＂ manufactured by compression. In the first part of this work, the solubility and the metastable zone width have been determined experimentally for the coating solution because they are essential factors for any crystallization process. In the second part, the coating process is investigated on the operating conditions that affect the surface morphology and the crystal growth rate. These experimental conditions include concentration of the coating solution, degree of sub-cooling, agitation speed, retention time, and surface properties of the naked ibuprofen tablets. The results show that naked tablet coating by cooling crystallization is feasible and can be applied in the pharmaceutical industry.

关键词： coating solution crystallization ibuprofen tablets sucrose

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Etching Effect on CMP of Different GaN Layers

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稀有金属材料与工程 2011年第S3期40卷 276-280页

作者： Siche Dietmar Rost Hans-joachim Schulz Tobias Albrecht Martin Institute of Crystal Growth Max-Born-Str. 2 12489 Berlin Germany

Chemical mechanical polishing (CMP) was used to etch various GaN materials, such as GaN layers on sapphire and silicon carbide substrates grown by metal-organic chemical vapor deposition and thick GaN layers grown by physical vapor transport. It was found that CMP could reveal the dislocations in GaN surfaces due to a selective etching component. After the optimization of CMP condition, the surface finish improved and the subsurface damage was almost completely removed, demonstrated by atomic force microscopy and an electron back-scattered diffraction technique. This study established the correlation between the dislocation density and film quality. The crystalline perfection and optical properties of GaN layers were characterized by high resolution X-ray diffraction and photoluminescence.

关键词： surface etch pits CMP GaN

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Stability of the linear chain structure for 12C in covariant density functional theory on a 3D lattice

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Science China(Physics,Mechanics & Astronomy) 2019年第11期62卷 6-13页

作者： ZhengXue Ren ShuangQuan Zhang PengWei Zhao Naoyuki Itagaki joachim AMaruhn Jie Meng State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Yukawa Institute for Theoretical Physics Kyoto UniversityKyoto 606-8502Japan Institut fur Theoretische Physik Goethe-UniversitatMax-von-Laue-Str.160438 Frankfurt am MainGermany Department of Physics University of StellenboschStellenbosch 7600South Africa

The stability of the linear chain structure of three α clusters for 12C against the bending and fission is investigated in the cranking covariant density functional theory, in which the equation of motion is solved on a 3D lattice with the inverse Hamiltonian and the Fourier spectral methods. Starting from a twisted three α initial configuration, it is found that the linear chain structure is stable when the rotational frequency is within the range of ~2.0-~2.5 MeV. Beyond this range, the final states are not stable against fission. By examining the density distributions and the occupation of single-particle levels, however, these fissions are found to arise from the occupation of unphysical continuum with large angular momenta. To properly remove these unphysical continuum, a damping function for the cranking term is introduced. Eventually, the stable linear chain structure could survive up to the rotational frequency ~3.5 MeV, but the fission still occurs when the rotational frequency approaches ~4.0 MeV.

关键词： covariant density functional theory cranking model 3D lattice space linear chain structure alpha-cluster structure collective rotation 12C

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Efficiency of sample-based indices for spatial pattern recognition of wild pistachio(Pistacia atlantica) trees in semi-arid woodlands

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Journal of Forestry Research 2016年第3期27卷 583-594页

作者： Yousef Erfanifard joachim Saborowski Kerstin Wiegand Katrin M.Meyer Department of Natural Resources and Environment College of Agriculture Shiraz University Department of Ecosystem Modelling University of Goettingen

The efficiency of sample-based indices proposed to quantify the spatial distribution of trees is influenced by the structure of tree stands, environmental heterogeneity and degree of aggregation. We evaluated 10 commonly used distance-based and 10 density-based indices using two structurally different stands of wild pistachio trees in the Zagros woodlands, Iran, to assess the reliability of each in revealing stand structure in woodlands. All trees were completely stem-mapped in a nearly pure（40 ha） and a mixed（45 ha） stand. First, the inhomogeneous pair correlation function [g（r）] and the Clark-Evans index（CEI） were used as references to reveal the true spatial arrangement of all trees in these stands. The sampled data were then evaluated using the 20 *** was undertaken in a grid based on a square lattice using square plots（30 m 9 30 m） and nearest neighbor distances at the sample points. The g（r） and CEI statistics showed that the wild pistachio trees were aggregated in both stands, although the degree of aggregation was markedly higher in the pure stand. Three distance- and six density-based indices statistically verified that the wild pistachio trees were aggregated in both stands. The distance-based Hines and Hines statistic（ht） and the densitybased standardised Morisita（Ip）, patchiness（IP） and Cassie（CA） indices revealed aggregation of the trees in the two structurally different stands in the Zagros woodlands and the higher clumping in the pure stand, whereas the other indices were not sensitive enough.

关键词： Density-based indices Distance-basedindices Pattern recognition Wild pistachio Woodland

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Initial nucleation of amorphous Si–B–C–N ceramics derived from polymer-precursors

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Journal of Materials Science & Technology 2019年第12期35卷 2851-2858页

作者： Ling-yan Li Hui Gu Vesna Srot Peter van Aken joachim Bill Materials Genome Institute School of Materials Science and EngineeringShanghai University99 Shangda RoadShanghai200444China Stuttgart Center for Electron Microscopy Max-Planck-lnstitute for Solid-State ResearchHeisen bergs trasse 370569StuttgartGermany Institute of Materials Science University of StuttgartHeisenbergstrasse 570569StuttgartGermany

Nucleation behavior of amorphous Si–B–C–N ceramics derived from boron-modified polyvinylsilazane procusors was systematically investigated by transmission electron microscopy(TEM) combined with spatially-resolved electron energy-loss spectroscopy(EELS) analysis. The ceramics were pyrolyzed at1000℃ followed by further annealing in N2, and SiC nano-crystallites start to emerge at 1200℃ and dominate at 1500℃. Observed by high-angle annular dark-field imaging, bright and dark clusters were revealed as universal nano-structured features in ceramic matrices before and after nucleation, and the growth of cluster size saturated before reaching 5 nm at 1400℃. EELS analysis demonstrated the gradual development of bonding structures successively into SiC, graphetic BNCxand Si3N4 phases, as well as a constant presence of unexpected oxygen in the matrices. Furthermore, EELS profiling revealed the bright SiC clusters and less bright Si3N4-like clusters at 1200–1400℃. Since the amorphous matrix has already phase separated into SiCN and carbon clusters, another phase separation of SiCN into SiC and Si3N4-like clusters might occur by annealing to accompany their nucleation and growth, albeit one crystallized and another remained in amorphous structure. Hinderance of the cluster growth and further crystallization was owing to the formation of BNCxlayers that developed between SiC and Si3N4-like clusters as well as from the excessive oxygen to form the stable SiO2.

关键词： Precursor derived ceramics Si–B–C–N Nucleation High-angle annular dark-field imaging Electron energy-loss spectroscopy

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Condition-dependence and sexual ornamentation： Effects of immune challenges on a highly sexually dimorphic grasshopper

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Insect Science 2018年第4期25卷 617-630页

作者： J. Pablo Valverde Hendrik Eggert joachim Kurtz Holger Schielzeth Department of Evolutionary Biology Bielefeld University Bielefeld Germany Institute for Evolution and Biodiversity Westfalische Wilhelms-Universitat Munster Munster Germany and 3 Department of Population Ecology Institute of Ecology Friedrich Schiller University Jena Germany Department of Population Ecology Institute of Ecology Friedrich Schiller University Jena Germany

Sexual ornaments contribute substantially to phenotypic diversity and it is particularly relevant to understand their evolution. Ornaments can assume the function of signals-of-quality that the choosy sex uses to evaluate potential mating partners. Often there are no obvious direct benefits and investment into mate choice is primarily rewarded by beneficial alleles that are inherited to the offspring. Inter-sexual communication via sexual ornaments requires honesty of the sexual signal, yet the question of what maintains honesty remains only partially solved. One solution is that honesty is maintained by trait expression being dependent on individual condition, since condition-dependent trait expression offers an effectively inexhaustible source of genetic variability. Here we test in the highly sexually dimorphic club-legged grasshopper Gomphocerus sibiricus if putative sexual ornaments, in particular the striking front-leg clubs, are more strongly affected by a lipopolysaccharide （LPS） immune challenge than putatively not sexually selected traits. Our results show overall little condition-dependent expression of morphological and song traits, with sexually selected traits exhibiting effects comparable to nonsexually selected traits （with the possible exception of stridulatory file length and syllable-to-pause ratio in advertisement songs）. Interestingly, field observations of individuals of lethally parasitized individuals suggest that a very strong environmental challenge can specifically affect the expression of the front-leg clubs. The presence of 1% of males in natural populations with missing or heavily deformed clubs plus 5% with minor club deformations furthermore indicate that there are risks associated with club development during final ecdysis and this might act as a filter against deleterious alleles.

关键词： Acrididae honest signaling Orthoptera phenotypic plasticity sexualselection

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