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Sperm traits differ between winged and wingless males of the ant Cardiocondyla obscurior

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Integrative Zoology 2016年第6期11卷 427-432页

作者： Alexandra SCHREMPF Astrid MOSER jacques DELABIE j.rgen heinze Zoology/Evolutionary Biology University of RegensburgRegensburgGermany Myrmecological Laboratory Cocoa Research Center CEPLACItabunaBrazil

Size and shape of sperm cells vary tremendously throughout the animal *** adaptive significance of this variation is not fully *** addition to sperm-female interactions and the environmental conditions,the risk of sperm competition might affect number,morphology and other“quality”traits of *** the male-diphenic ant Cardiocondyla obscurior,winged sneaker males have limited sperm number,because their testes degenerate shortly after adult emergence,as is typical for males of social *** contrast,wingless fighter males continuously replenish their sperm supply due to their exceptional lifelong spermatogene*** winged males usually have to compete with several other winged males for virgin queens,wingless males are able to monopolize queens by killing all other ***,this presents a unique system to investigate how alternative reproductive tactics and associated physiology affect sperm morphology and *** found that sperm-limited males invest into sperm number instead of sperm *** in sperm length is smaller in winged males,probably reflecting that they have to compete with several other ***,sperm viability is equally high in both male phenotypes.

关键词： alternative reproductive tactic social insect sperm length sperm viability

Cuticular hydrocarbons in two parapatric species of ants and their hybrid

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Integrative Zoology 2011年第3期6卷 259-265页

作者： Mohamed EL-SHEHABY Mohamed Sayed SALAMA Elisabeth BRUNNER j.rgen heinze Biologie I University of RegensburgRegensburgGermany Department of Entomology Ain Shams UniversityCairoEgypt

Discrimination between nestmates and non-nestmates in social insects is thought to rely on the pattern of cuticular *** investigated the cuticular hydrocarbon profiles of 2 parapatric sibling ant species,Temnothorax nylanderi(Förster,1850)and Temnothorax crassispinus(Karavaiev,1926),and their *** found that although the profiles show considerable similarities,a discriminant analysis based on the relative peak areas of cuticular hydrocarbons separates the 3 *** profiles of hybrids were not consistently intermediate between those of the paternal species,suggesting either non-additive interactions among the parental biosynthetic pathways or systematic differ-ences in environment-derived odor cues.

关键词： colony odor cuticular hydrocarbons hybridization Temnothorax

Electric-field driven stability control of skyrmions in an ultrathin transition-metal film

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npj Computational Materials 2022年第1期8卷 992-1000页

作者： Souvik Paul Stefan heinze Peter Grünberg Institut and Institute for Advanced Simulation Forschungszentrum Jülich and JARA52425JülichGermany Institute of Theoretical Physics and Astrophysics Christian-Albrechts-Universität zu KielLeibnizstrasse 1524098KielGermany

To realize future spintronic applications with magnetic skyrmions—topologically nontrivial swirling spin structures—it is essential to achieve efficient writing and deleting capabilities of these ***-field assisted nucleation and annihilation is a promising route,however,the understanding of the underlying microscopic mechanisms is still ***,we show how the stability of individual magnetic skyrmions in an ultrathin transition-metal film can be controlled via external electric *** demonstrate based on density functional theory that it is important to consider the changes of all interactions with electric field,i.e.,the pair-wise exchange,the Dzyaloshinskii–Moriya interaction,the magnetocrystalline anisotropy energy,and the higher-order exchange *** energy barriers for electric-field assisted skyrmion writing and deleting obtained via atomistic spin simulations vary by up to a factor of three more than the variations of the interactions calculated from *** surprising effect originates from the electric-field dependent size of metastable skyrmions at a fixed magnetic *** large changes in lifetimes allow the possibility of electric-field assisted thermally activated writing and deleting of skyrmions.

关键词： field stability film

Microcrack Formation During Gas Metal Arc Welding of High-Strength Fine-Grained Structural Steel

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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 140-148页

作者： Christoph heinze Thomas Michael Andreas Pittner Michael Rethmeier Division 9.3 "Welding Technology" BAM Federal Institute for Materials Research and TestingUnter den Eichen 8712205 BerlinGermany joining and Coating Technology Fraunhofer-Institute for Production Systems and Design Technology IPKPascalstraβe 8-910587 BerlinGermany

The recent development of high-performance-modified spray arc processes in gas metal arc welding due to modern digital control technology and inverter power sources enables a focused spray arc, which results in higher penetration depths and welding speed. However, rnicrocracks occurred in the weld metal while approaching the process limits of the modified spray arc, represented by a 20-mm double layer DV-groove butt-weld, These cracks were detected in structural steel exhibiting a yield strength level of up to 960 MPa and are neither dependent on the used weld power source nor a consequence of the modified spray arc process itself. The metallographic and fractographic investigations of the rather exceptional fracture surface lead to the classification of the microcracks as hot cracks, The effects of certain welding parameters on the crack probability are clarified using a statistical design of experiment. However, these microcracks do not impact the design specification for toughness in the Charpy V-notch test （absorbed energy at -40 ℃ for the present material is 30 j）.

关键词： High-strength low-alloy steel Welding Fracture Design of experiments Microcracking

Numerical sensitivity analysis of welding-induced residual stress depending on variations in continuous cooling transformation behavior

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Frontiers of Materials Science 2011年第2期5卷 168-178页

作者： C. heinze C. SCHWENK M. RETHMEIER j. CARON Federal Institute for Materials Research and Testing Division 5.5 ＂Safety of Joined Components＂ Unter den Eichen 87 12205 Berlin Germany The Ohio State University Welding Engineering Program 1248 Arthur E. Adams Drive Columbus Ohio 43221 USA

The usage of continuous cooling transformation （CCT） diagrams in numerical welding simulations is state of the art. Nevertheless, specifications provide limits in chemical composition of materials which result in different CCT behavior and CCT diagrams, respectively. Therefore, it is necessary to analyze the influence of variations in CCT diagrams on the developing residual stresses. In the present paper, four CCT diagrams and their effect on numerical calculation of residual stresses are investigated for the widely used structural steel S355j2 ＋ N welded by the gas metal arc welding （GMAW） process. Rather than performing an arbitrary adjustment of CCT behavior, four justifiable data sets were used as input to the numerical calculation： data available in the Sysweld database, experimental data acquired through Gleeble dilatometry tests, and TTTICCT predictions calculated from the jMatPro and Edison Welding Institute （EWI） Virtual joining Portal software. The performed numerical analyses resulted in noticeable deviations in residual stresses considering the different CCT diagrams. Furthermore, possibilities to improve the prediction of distortions and residual stress based on CCT behavior are discussed.

关键词： welding simulation GMAW CCT sensitivity welding residual stress

Influence of experimental soil disturbances on the diversity of plants in agricultural grasslands

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journal of Plant Ecology 2014年第6期7卷 509-517页

作者： jörg Müller johannes heinze jasmin joshi Steffen Boch Valentin H.Klaus Markus Fischer Daniel Prati Institute of Biochemistry and BiologyUniversity of PotsdamMaulbeerallee 114469 PotsdamGermany Freie Universität Berlin Institut für BiologieBerlin-Brandenburg Institute of Advanced Biodiversity ResearchAltensteinstrasse 614195 BerlinGermany Institute of Plant Sciences University of BernAltenbergrain 213013 BernSwitzerland Institute of Landscape Ecology University of MünsterHeisenbergstr.248149 MünsterGermany Biodiversity and Climate Research Centre BIK-F Senckenberg Gesellschaft für Naturforschung603257 FrankfurtGermany

Aims and Methods Disturbance is supposed to play an important role for biodiversity and ecosystem stability as described by the intermediate disturbance hypoth-esis(IDH),which predicts highest species richness at intermediate levels of *** this study,we tested the effects of artificial soil distur-bances on diversity of annual and perennial vascular plants and bryo-phytes in a field experiment in 86 agricultural grasslands differing in land use in two regions of *** each grassland,we implemented four treatments:three treatments differing in application time of soil dis-turbances and one *** year after experimental disturbance,we recorded vegetation and measured biomass productivity and bare *** analysed the disturbance response taking effects of region and land-use-accompanied disturbance regimes into *** Findings Region and land-use type strongly determined plant species *** disturbances had small positive effects on the species richness of annuals,but none on perennials or *** ground was positively related to species richness of ***,exceeding the creation of 12%bare ground further distur-bance had a detrimental effect on bryophyte species richness,which corresponds to the *** biomass productivity was unaffected by disturbance our results indicate that the disturbance effect on spe-cies richness of annuals was not due to decreased overall produc-tivity,but rather due to short-term lowered inter-and intraspecific competition at the newly created ***,our results highlight the importance of soil disturbances for species richness of annual plants and bryophytes in agricultural ***,most grasslands were disturbed naturally or by land-use practices and our additional experimental soil dis-turbances only had a small short-term ***,total plant diversity in grasslands seemed to be more limited by the availabil-ity of propagules rather tha

关键词： annuals bryophytes colonization intermediate disturbance hypothesis microsites

Characterization of gut microbiome and metabolome in Helicobacter pylori patients in an underprivileged community in the United States

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World journal of Gastroenterology 2021年第33期27卷 5575-5594页

作者： Brian White john D Sterrett Zoya Grigoryan Lauren Lally jared D heinze Hyder Alikhan Christopher A Lowry Lark j Perez joshua DeSipio Sangita Phadtare Department of Biomedical Sciences Cooper Medical School of Rowan UniversityCamdenNJ 08103United States Department of Integrative Physiology University of Colorado BoulderBoulderCO 80309United States Department of Internal Medicine Lenox Hill HospitalNYCNY 10075United States Department of Internal Medicine Thomas Jefferson University HospitalPhiladelphiaPA 19107United States Department of Biological Sciences Rowan UniversityGlassboroNJ 08028United States Department of Chemistry and Biochemistry Rowan UniversityGlassboroNJ 08028United States Department of Gastroenterology Cooper University HospitalCamdenNJ 08103United States

BACKGROUND Helicobacter pylori(***),a bacterium that infects approximately half of the world’s population,is associated with various gastrointestinal diseases,including peptic ulcers,non-ulcer dyspepsia,gastric adenocarcinoma,and gastric *** the burden of antibiotic resistance increases,the need for new adjunct therapies designed to facilitate *** eradication and reduce negative distal outcomes associated with infection has become more *** of the interactions between ***,the fecal microbiome,and fecal fatty acid metabolism,as well as the mechanisms underlying these interactions,may offer new therapeutic *** To characterize the gut microbiome and metabolome in *** patients in a socioeconomically challenged and underprivileged inner-city *** Stool samples from 19 *** patients and 16 control subjects were analyzed.16S rRNA gene sequencing was performed on normalized pooled amplicons using the Illumina MiSeq System using a MiSeq reagent kit *** and beta diversity analyses were performed in QIIME ***-targeted fatty acid analysis of the samples was carried out using gas chromatography-mass spectrometry,which measures the total content of 30 fatty acids in stool after conversion into their corresponding fatty acid methyl ***-dimensional scaling(MDS)was performed on Bray-Curtis distance matrices created from both the metabolomics and microbiome datasets and a Procrustes test was performed on the metabolomics and microbiome MDS *** Fecal microbiome analysis showed that alpha diversity was lowest in *** patients over 40 years of age compared to control subjects of similar age *** diversity analysis of the samples revealed significant differences in microbial community structure between *** patients and control subjects across all ***-eight and six taxa had lower and higher relative abundance in *** patients,*** that were e

关键词： Gut microbiome Metabolome Helicobacter pylori Antibiotic resistance Dysbiosis Eradication

Toward room-temperature nanoscale skyrmions in ultrathin films

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npj Computational Materials 2020年第1期6卷 58-68页

作者： Anastasiia SVarentcova Stephan von Malottki Maria N.Potkina Grzegorz Kwiatkowski Stefan heinze Pavel F.Bessarab ITMO University St.Petersburg 197101Russia Science Institute University of IcelandReykjavík 107Iceland Kavli Institute of Nanoscience Delft University of TechnologyP.O.Box 4056Delft 2600 GAThe Netherlands Institute of Theoretical Physics and Astrophysics University of KielLeibnizstrasse 15Kiel 24098Germany St.Petersburg State University St.Petersburg 198504Russia Peter Grünberg Institute and Institute for Advanced Simulation Forschungszentrum JülichJülich 52425Germany

Breaking the dilemma between small size and room-temperature stability is a necessary prerequisite for skyrmion-based information *** we demonstrate by means of rate theory and an atomistic spin Hamiltonian that the stability of isolated skyrmions in ultrathin ferromagnetic films can be enhanced by the concerted variation of magnetic interactions while keeping the skyrmion size *** predict film systems where the lifetime of sub-10 nm skyrmions can reach years at ambient conditions.

关键词： conditions stability films

Organic carbon dynamics and enzyme activities in agricultural soils amended with biogas slurry, liquid manure and sewage sludge

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Agricultural Sciences 2012年第1期3卷 104-113页

作者： Britta Stumpe Steffen Werner Robert jung Stefanie heinze Elisabeth jüschke Christian Strippel Bernd Marschner Department Soil Science/Soil Ecology Institute of Geography Ruhr-University Bochum Bochum Germany

The application of organic soil amendments is a common practice for increasing soil fertility and soil organic carbon (SOC) content. In recent years, a new product from biogas production, biogas slurry is increasingly applied to agricultural soils, although little is known about its effects on soil properties. In this study, the influence of this new product in comparison with liquid manure and sewage sludge on the organic carbon dynamics and enzyme activities were investigated in two different agricultural soils in short-term incubation studies. As a control, biologically inert sand was also amended with these organic wastes. In sand, biogas slurry degraded to 10.4% within 14 days, while no differences were found between the degradability of liquid manure and sewage sludge with 6.6% and 5.4%, respectively. However, although the degradability of biogas slurry was highest among the organic amendments, liquid manure application resulted in the highest respiration rates in the soil samples. This was likely due to the organic waste borne easily decomposable substrates which were most dominant in liquid manure. Organic waste applications were found to generally increase the activity of numerous enzymes but did not change the soil enzyme patterns. Thus, in general it was shown that the microbial population of the organic wastes will not become prominent when introduced with the manures to soils. Thus, an inoculation with organic waste borne microorganisms could likely be neglected when discussing the extent of organic carbon dynamics after organic waste application to agricultural soils.

关键词： Biogas Slurry Organic Wastes Organic Carbon Dynamics Enzyme Activity Priming Effects