96 results on '"Peter Fleischmann"'
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2. Rezension von: Fleischmann, Peter (Bearb.), Die handgezeichneten Karten des Staatsarchivs Nürnberg bis 1806
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Andreas Maisch and Peter Fleischmann
- Abstract
Peter Fleischmann (Bearb.), Die handgezeichneten Karten des Staatsarchivs Nürnberg bis 1806 (Bayerische Archivinventare, Bd. 49), München (Generaldirektion der Archive Bayerns) 1998. 566 S.
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- 2023
3. Simple Mesh Examples to Illustrate Specific Finite Element Mesh Requirements.
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Peter Fleischmann, Robert Kosik, and Siegfried Selberherr
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- 1999
4. Rezension von: Bühl, Charlotte; Fleischmann, Peter (Hrsg.), Festschrift Rudolf Endres
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Eberhard Göpfert, Charlotte Bühl-Gramer, and Peter Fleischmann
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Festschrift Rudolf Endres: Zum 65. Geburtstag gewidmet von Kollegen, Freunden und Schülern. Hg. von Charlotte Bühl und Peter Fleischmann, Neustadt/Aisch (Degener) 2000, 855 S.
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- 2023
5. Rezension von: Fuchs, Stefan, Herrschaftswissen und Raumerfassung im 16. Jahrhundert
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Peter Fleischmann and Stefan Fuchs
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Stefan Fuchs, Herrschaftswissen und Raumerfassung im 16. Jahrhundert. Kartengebrauch im Dienste des Nürnberger Stadtstaates (Veröffentlichungen des Nationalen Forschungsschwerpunkts Medienwandel – Medienwechsel – Medienwissen, Historische Perspektiven 35), Zürich: Chronos Verlag 2018. 312 S., 31 Farbabb. ISBN 978-3-0340-1346-8. € 48,–/CHF 48,–
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- 2022
6. Carotenoid-Derived Aroma Compounds
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Peter Winterhalter, Russell L. Rouseff, Peter Winterhalter, Russell Rouseff, Holger Knapp, Markus Straubinger, Carola Stingl, Peter Winterhalter, Markus Herderich, Hans-Ulrich Humpf, Jane E. Friedrich, Terry E. Acree, Peter Fleischmann, Andrea Lutz-Röder, Peter Winterhalter, Naoharu Watanabe, Masayu
- Published
- 2001
7. The finite unipotent groups consisting of bireflections
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Katherine Horan and Peter Fleischmann
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Ring (mathematics) ,Pure mathematics ,Algebra and Number Theory ,010102 general mathematics ,Field (mathematics) ,Codimension ,Unipotent ,Space (mathematics) ,01 natural sciences ,010101 applied mathematics ,Converse ,0101 mathematics ,Element (category theory) ,QA ,Subspace topology ,Mathematics - Abstract
Let k be a field of characteristic p and V a finite-dimensional k-vector space. An element g ∈ GL ( V ) {g\in{\rm GL}(V)} is called a bireflection if it centralizes a subspace of codimension less than or equal to 2. It is known by a result of Kemper that if for a finite p-group G ≤ GL ( V ) {G\leq{\rm GL}(V)} the ring of invariants Sym ( V * ) G {{\rm Sym}(V^{*})^{G}} is Cohen–Macaulay, G is generated by bireflections. Although the converse is false in general, it holds in special cases e.g. for particular families of groups consisting of bireflections. In this paper we give, for p > 2 {p>2} , a classification of all finite unipotent subgroups of GL ( V ) {{\rm GL}(V)} consisting of bireflections. Our description of the groups is given explicitly in terms useful for exploring the corresponding rings of invariants. This further analysis will be the topic of a forthcoming paper.
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- 2018
8. Nürnberg in den 1640er Jahren
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Peter Fleischmann
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- 2019
9. Stable transcendence for formal power series, generalized Artin-Schreier polynomials and a conjecture concerning p-groups
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Chris F. Woodcock and Peter Fleischmann
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Transcendence (philosophy) ,Conjecture ,Formal power series ,General Mathematics ,010102 general mathematics ,Field (mathematics) ,Function (mathematics) ,01 natural sciences ,Combinatorics ,0103 physical sciences ,Prime characteristic ,010307 mathematical physics ,Krull dimension ,0101 mathematics ,Abelian group ,Mathematics - Abstract
Let f(x) be a formal power series with coefficients in the field k and let n ? 1. We define the notion of n-transcendence of f(x) over k and, more generally, the stable transcendence function dk(f(x), n). It is shown that, if k has prime characteristic p, this function determines the minimal Krull dimension dk(G) of the universal modular Galois-algebras of an elementary Abelian p-group G, introduced in [2, 3, 4, 5]. Since the concept of n-transcendence is of independent interest in all characteristics, a number of fundamental theorems are proved where the generalized Artin-Schreier polynomials surprisingly play a central role. We make a plausible conjecture in the case when k = Fp, the truth of which would imply a conjectural result concerning dFp (G) previously investigated by the authors.
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- 2018
10. Free actions ofp-groups on affine varieties in characteristicp
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Peter Fleischmann and Chris F. Woodcock
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Discrete mathematics ,Pure mathematics ,Finite group ,Ring (mathematics) ,Group (mathematics) ,General Mathematics ,Polynomial ring ,010102 general mathematics ,Field (mathematics) ,01 natural sciences ,Invariant theory ,0103 physical sciences ,ComputingMethodologies_DOCUMENTANDTEXTPROCESSING ,010307 mathematical physics ,Abelian category ,0101 mathematics ,Algebraically closed field ,QA ,Mathematics - Abstract
LetKbe an algebraically closed field and$\mathbb{A}$n≅Knaffinen-space. It is known that a finite group$\frak{G}$can only act freely on$\mathbb{A}$nifKhas characteristicp> 0 and$\frak{G}$is ap-group. In that case the group action is “non-linear” and the ring of regular functionsK[$\mathbb{A}$n] must be atrace-surjectiveK−$\frak{G}$-algebra.Now letkbe an arbitrary field of characteristicp> 0 and letGbe a finitep-group. In this paper we study the category$\mathfrak{Ts}$of all finitely generated trace-surjectivek−Galgebras. It has been shown in [13] that the objects in$\mathfrak{Ts}$are precisely those finitely generatedk−GalgebrasAsuch thatAG≤Ais a Galois-extension in the sense of [7], with faithful action ofGonA. Although$\mathfrak{Ts}$is not an abelian category it has “s-projective objects”, which are analogues of projective modules, and it has (s-projective) categorical generators, which we will describe explicitly. We will show thats-projective objects and their rings of invariants are retracts of polynomial rings and therefore regular UFDs. The category$\mathfrak{Ts}$also has “weakly initial objects”, which are closely related to the essential dimension ofGoverk. Our results yield a geometric structure theorem for free actions of finitep-groups on affinek-varieties. There are also close connections to open questions on retracts of polynomial rings, to embedding problems in standard modular Galois-theory ofp-groups and, potentially, to a new constructive approach to homogeneous invariant theory.
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- 2017
11. The invariant rings of the Sylow groups of GU(3,q2), GU(4,q2), Sp(4,q) and O+(4,q) in the natural characteristic
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Peter Fleischmann and Jorge N.M. Ferreira
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Classical group ,Discrete mathematics ,Algebra and Number Theory ,Symplectic group ,Invariant polynomial ,010102 general mathematics ,Sylow theorems ,Complete intersection ,010103 numerical & computational mathematics ,01 natural sciences ,Unitary state ,Combinatorics ,Computational Mathematics ,QA150 ,Orthogonal group ,0101 mathematics ,Invariant (mathematics) ,Mathematics - Abstract
Let G be a Sylow p -subgroup of the unitary groups GU(3,q2)GU(3,q2), GU(4,q2)GU(4,q2), the symplectic group Sp(4,q)Sp(4,q) and, for q odd, the orthogonal group O+(4,q)O+(4,q). In this paper we construct a presentation for the invariant ring of G acting on the natural module. In particular we prove that these rings are generated by orbit products of variables and certain invariant polynomials which are images under Steenrod operations, applied to the respective invariant form defining the corresponding classical group. We also show that these generators form a SAGBI basis and the invariant ring for G is a complete intersection.
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- 2017
12. Characterization of human papillomavirus 6b L1 virus-like particles isolated from silkworms using capillary zone electrophoresis
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Hermann Wätzig, Enoch Y. Park, Thomas Hahne, Tatsuya Kato, Muthukutty Palaniyandi, and Peter Fleischmann
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viruses ,Size-exclusion chromatography ,Gene Expression ,Bioengineering ,Biology ,Applied Microbiology and Biotechnology ,Virus ,Capillary electrophoresis ,Dynamic light scattering ,Animals ,Humans ,Papillomavirus Vaccines ,Vaccines, Virus-Like Particle ,Human papillomavirus ,Chromatography ,fungi ,virus diseases ,Electrophoresis, Capillary ,Bombyx ,Human papillomavirus 6 ,Nucleopolyhedroviruses ,Blot ,Bombyx mori nucleopolyhedrovirus ,Capsid Proteins ,Ultracentrifuge ,Biotechnology - Abstract
Human papillomavirus 6b L1 virus-like particles (VLPs) were successfully expressed using Bombyx mori nucleopolyhedrovirus (BmNPV) bacmid expression system and rapidly purified using size exclusion chromatography after ultracentrifugation procedure and characterized by capillary zone electrophoresis (CZE). The average capillary electrophoresis migration time was 11 min with the relative standard deviation (RSD) of 0.3% of human papillomavirus 6b L1 VLPs. After this threefold fractionation, the CZE samples were still further investigated by dynamic light scattering and immuno blotting. The versatile technique, CZE not only proved to be a valuable tool for VLP characterization, but was also found to be reliable and precise. Thus CZE will also be an important option for the quality control of VLPs in pharmaceutical research level.
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- 2014
13. Occurrence of Glycosidically Conjugated 1-Phenylethanol and Its Hydrolase β-Primeverosidase in Tea (Camellia sinensis) Flowers
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Fang Dong, Aiko Kunimasa, Sihua Cheng, Ling Zhang, Ariaki Murata, Ziyin Yang, Frank Mayer, Naoharu Watanabe, Peter Fleischmann, Ying Zhou, Yuqian Zhang, and Jiamin Lu
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Crops, Agricultural ,China ,Spectrometry, Mass, Electrospray Ionization ,Molar concentration ,Glycoside Hydrolases ,Flowers ,Conjugated system ,medicine.disease_cause ,Camellia sinensis ,Gas Chromatography-Mass Spectrometry ,Substrate Specificity ,law.invention ,Hydrolysis ,Gene Expression Regulation, Plant ,law ,Hydrolase ,medicine ,Glycosides ,Food science ,Nuclear Magnetic Resonance, Biomolecular ,Escherichia coli ,Benzyl Alcohols ,Chromatography, High Pressure Liquid ,Plant Proteins ,Molecular Structure ,Chemistry ,food and beverages ,General Chemistry ,Phenylethyl Alcohol ,Recombinant Proteins ,Biochemistry ,Odorants ,Recombinant DNA ,Food Additives ,General Agricultural and Biological Sciences - Abstract
A previous study found that 1-phenylethanol (1PE) was a major endogenous volatile compound in tea (Camellia sinensis) flowers and can be transformed to glycosically conjugated 1PE (1PE-Gly). However, occurrences of 1PE-Gly in plants remain unknown. In this study, four 1PE-Glys have been isolated from tea flowers. Three of them were determined as (R)-1PE β-d-glucopyranoside ((R)-1PE-Glu), (S)-1PE-Glu, and (S)-1PE β-primeveroside ((S)-1PE-Pri), respectively, on the basis of NMR, MS, LC-MS, and GC-MS evidence. The other one was identified as (R)-1PE-Pri on the basis of LC-MS and GC-MS data. Moreover, these 1PE-Glys were chemically synthesized as the authentic standards to further confirm their occurrences in tea flowers. 1PE-Glu had a higher molar concentration than 1PE-Pri in each floral stage and organ. The ratio of (R) to (S) differed between 1PE-Glu and 1PE-Pri. In addition, a 1PE-Gly hydrolase β-primeverosidase recombinant protein produced in Escherichia coli exhibited high hydrolysis activity toward (R)-1PE-Pri. However, β-primeverosidase transcript level was not highly expressed in the anther part, which accumulated the highest contents of 1PE-Gly and 1PE. This suggests that 1PE-Gly may not be easily hydrolyzed to liberate 1PE in tea flowers. This study provides evidence of occurrences of 1PE-Glys in plants for the first time.
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- 2014
14. Purification and Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry of Aroma Compounds from Green Tea Products and Comparison to Bulk Analysis
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Ulrich H. Engelhardt, Peter Fleischmann, Naohiro Yoshida, Andreas Hilkert, Dieter Juchelka, Keita Yamada, Peter Winterhalter, Naoharu Watanabe, Toshiyuki Ohnishi, and Ariaki Murata
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Carbon Isotopes ,Chromatography ,Tea ,Isotope ,Chemistry ,General Chemistry ,Phenylethyl Alcohol ,Mass spectrometry ,High-performance liquid chromatography ,Camellia sinensis ,Gas Chromatography-Mass Spectrometry ,Plant Leaves ,chemistry.chemical_compound ,Benzyl alcohol ,Isotopes of carbon ,Enzymatic hydrolysis ,Odorants ,Glycosides ,Gas chromatography ,Isotope-ratio mass spectrometry ,Hexanols ,General Agricultural and Biological Sciences ,Chromatography, High Pressure Liquid ,Food Analysis ,Benzyl Alcohol - Abstract
A method for carbon isotope ratio (δ(13)C) analysis was developed for compound-specific isotope analysis of tea volatiles, and the values were compared with the δ(13)C value from bulk isotope analyses. The δ(13)C value of 2-phenylethanol liberated via enzymatic hydrolysis of the 2-phenylethyl β-primeveroside standard was examined first. Isotope fractionations for 2-phenylethyl β-primeveroside from preparative high-performance liquid chromatography (HPLC) were also analyzed. The enzymatic treatment and the preparative HPLC process did not cause carbon isotope fractionations, substantiating the strategies available for δ(13)C analysis of volatile compounds. On the basis of the gas chromatography-combustion-isotope ratio mass spectrometry data from 2-phenylethanol, it was possible to derive the conditions for enzyme treatment and preparative HPLC of the glycoconjugates of 2-phenylethanol, (Z)-3-hexenol, and benzyl alcohol isolated from green tea leaves. Larger variations in δ(13)C were found for individual volatile compounds compared with bulk analytical data from the leaves, indicating the potential to utilize this strategy in assigning the geographical origin of green tea.
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- 2013
15. ON FINITE UNIPOTENT TRANSVECTION GROUPS AND THEIR INVARIANTS
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Peter Fleischmann
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Algebra ,General Mathematics ,Unipotent ,Transvection ,Mathematics - Published
- 2013
16. Galois ring extensions and localized modular rings of invariants of p-groups
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Peter Fleischmann and Chris F. Woodcock
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Discrete mathematics ,Principal ideal ring ,Reduced ring ,Pure mathematics ,Algebra and Number Theory ,Noncommutative ring ,Mathematics::Commutative Algebra ,Polynomial ring ,Boolean ring ,Primitive ring ,Simple ring ,Geometry and Topology ,Mathematics ,Group ring - Abstract
We apply recent results on Galois-ring extensions and trace surjective algebras to analyze dehomogenized modular invariant rings of finite p-groups, as well as related localizations. We describe criteria for the dehomogenized invariant ring to be polynomial or at least regular and we show that for regular affine algebras with possibly non-linear action by a p-group, the singular locus of the invariant ring is contained in the variety of the transfer ideal. If V is the regular module of an arbitrary finite p-group, or V is any faithful representation of a cyclic p-group, we show that there is a suitable invariant linear form, inverting which renders the ring of invariants into a “localized polynomial ring” with dehomogenization being a polynomial ring. This is in surprising contrast to the fact that for a faithful representation of a cyclic group of order larger than p, the ring of invariants itself cannot be a polynomial ring by a result of Serre. Our results here generalize observations made by Richman [R] and by Campbell and Chuai [CCH].
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- 2012
17. The Invariant Theory of Finite Groups
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Peter Fleischmann and James Shank
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- 2016
18. Influence of exogenously applied abscisic acid on carotenoid content and water uptake in flowers of the tea plant (Camellia sinensis )
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Naoharu Watanabe, Ziyin Yang, Peter Fleischmann, Susanne Baldermann, Akio Morita, Miwa Sakai, and Yasushi Todoroki
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chemistry.chemical_classification ,Biological pigment ,Lutein ,Nutrition and Dietetics ,organic chemicals ,fungi ,food and beverages ,Biology ,Zeaxanthin ,chemistry.chemical_compound ,Neoxanthin ,chemistry ,Xanthophyll ,Botany ,Camellia sinensis ,Food science ,Agronomy and Crop Science ,Carotenoid ,Abscisic acid ,Food Science ,Biotechnology - Abstract
BACKGROUND Carotenoids are a major class of plant pigments and fulfill many functions in different organisms that either produce or consume them. Although the color of the stamina of tea (Camellia sinensis) flowers is clearly due to the presence of carotenoids, the carotenoid profile and content remain to be discovered. RESULTS We investigated the carotenoid profile of tea flowers and determined changes in concentrations over the floral development. The flowers contained oxygenated xanthophylls such as neoxanthin, lutein and zeaxanthin, as well as the hydrocarbons β-carotene and α-carotene. Flowers of the tea plant contain to vegetables comparable amounts of carotenoids. The content of 9′-cis-epoxycarotenoids, which serve as abscisic acid precursors, as well as changes in concentration of abscisic acid were studied. The concentrations of carotenoids decreased whereas the abscisic acid content increased over the floral development. Exogenously applied S-abscisic acid affected water uptake, flower opening and carotenoid accumulation. CONCLUSION In summary, this paper reports, for the first time, the carotenoid profile and content of tea flowers. The study revealed that carotenoids in tea flowers are an interesting target in respect of possible applications of tea flower extracts as well as biological functions of abscisic acid during floral development. © 2012 Society of Chemical Industry
- Published
- 2012
19. Relative invariants, ideal classes and quasi-canonical modules of modular rings of invariants
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Chris F. Woodcock and Peter Fleischmann
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Factorial ,Pure mathematics ,Polynomial ring ,Modular rings of invariants ,Group Theory (math.GR) ,Commutative Algebra (math.AC) ,Relative invariants ,Group action ,FOS: Mathematics ,Representation Theory (math.RT) ,Invariant (mathematics) ,Mathematics ,Discrete mathematics ,Finite group ,Algebra and Number Theory ,Mathematics::Commutative Algebra ,business.industry ,Ideal classes ,Modular invariance ,13B05, 20C20 (Primary), 13B05, 13B40, 20C05 (Secondary) ,Modular design ,Mathematics - Commutative Algebra ,Quasi-canonical modules ,Factorial Gorenstein domains ,business ,Mathematics - Group Theory ,Mathematics - Representation Theory - Abstract
We describe "quasi canonical modules" for modular invariant rings $R$ of finite group actions on factorial Gorenstein domains. From this we derive a general "quasi Gorenstein criterion" in terms of certain 1-cocycles. This generalizes a recent result of A. Braun for linear group actions on polynomial rings, which itself generalizes a classical result of Watanabe for non-modular invariant rings. We use an explicit classification of all reflexive rank one $R$-modules, which is given in terms of the class group of $R$, or in terms of $R$-semi-invariants. This result is implicitly contained in a paper of Nakajima (\cite{Nakajima:rel_inv})., Comment: 16 pages
- Published
- 2011
20. Comparison of carotenoid and anthocyanin profiles of raw and boiled Solanum tuberosum and Solanum phureja tubers
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Silke Hillebrand, Lena Apel, Annika Burmeister, Claudia Kühne, Peter Fleischmann, and Sabine Bondiek
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chemistry.chemical_classification ,biology ,biology.organism_classification ,Solanum tuberosum ,chemistry.chemical_compound ,Dry weight ,chemistry ,Neoxanthin ,Xanthophyll ,Anthocyanin ,Botany ,Solanum ,Carotenoid ,Food Science ,Violaxanthin - Abstract
Tubers of the closely related species Solanum tuberosum (potatoes) and Solanum phureja belong to the staff of life for humans. The coloration of the often very colorful tubers is caused by carotenoids (especially xanthophylls) and anthocyanins. The new S. phureja cultivars Mayan Gold and Mayan Twilight, the new S. tuberosum cultivar Red Laura and the traditional S. tuberosum variety Shetland Black were analyzed for their pigment content. The dominant anthocyanin in the red-skinned cultivars Red Laura and Mayan Twilight was characterized as pelargonidin-3-coumarylrutinoside-5-glucoside by LC-ESI-MS. The blue pigment of the Shetland Black cultivar was petunidin-3-coumaroylrutinoside-5-glucoside. Red Laura contained 10 mg anthocyanins g −1 dry weight and Shetland Black 31 mg anthocyanins g −1 dry weight. The main carotenoids in raw tubers are 9- cis -violaxanthin, lutein and one unidentified carotenoid in all S. tuberosum and S. phureja cultivars. Minor compounds were identified as neoxanthin and neochrome. Additionally, zeaxanthin and one further unidentified carotenoid could be found in Red Laura and Mayan Gold. No differences in the carotenoid composition between peel and parenchyma could be found. Total carotenoid content ranged from 2.57 ± 0.53 μg g −1 dry weight in Shetland Black to 14.77 ± 2.22 μg g −1 dry weight in Red Laura (calculated as β-carotene-equivalents). In heat processed tubers, high amounts of carotenoids either changed from all-trans to 9- cis and 13- cis -isomeric form or was degraded. The total pigment content was decreased by heat processing in all cultivars. 8.23 ± 2.98 μg g −1 dry weight could be found in Mayan Twilight and 1.51 ± 0.31 μg carotenoids g −1 dry weight in Shetland Black.
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- 2011
21. Non-linear group actions with polynomial invariant rings and a structure theorem for modular Galois extensions
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Chris F. Woodcock and Peter Fleischmann
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Symmetric algebra ,Pure mathematics ,Mathematics::Commutative Algebra ,Galois cohomology ,General Mathematics ,Polynomial ring ,Galois theory ,Galois group ,Commutative ring ,Mathematics - Commutative Algebra ,Commutative Algebra (math.AC) ,Group action ,FOS: Mathematics ,Representation Theory (math.RT) ,Invariant (mathematics) ,13A50, 13B05, 20C20 (primary), 13B05, 13B40, 20C05 (secondary) ,Mathematics - Representation Theory ,Mathematics - Abstract
Let $G$ be a finite $p$-group and $k$ a field of characteristic $p>0$. We show that $G$ has a \emph{non-linear} faithful action on a polynomial ring $U$ of dimension $n=\mathrm{log}_p(|G|)$ such that the invariant ring $U^G$ is also polynomial. This contrasts with the case of \emph{linear and graded} group actions with polynomial rings of invariants, where the classical theorem of Chevalley-Shephard-Todd and Serre requires $G$ to be generated by pseudo-reflections. Our result is part of a general theory of "trace surjective $G$-algebras", which, in the case of $p$-groups, coincide with the Galois ring-extensions in the sense of \cite{chr}. We consider the \emph{dehomogenized symmetric algebra} $D_k$, a polynomial ring with non-linear $G$-action, containing $U$ as a retract and we show that $D_k^G$ is a polynomial ring. Thus $U$ turns out to be \emph{universal} in the sense that every trace surjective $G$-algebra can be constructed from $U$ by "forming quotients and extending invariants". As a consequence we obtain a general structure theorem for Galois-extensions with given $p$-group as Galois group and any prescribed commutative $k$-algebra $R$ as invariant ring. This is a generalization of the Artin-Schreier-Witt theory of modular Galois field extensions of degree $p^s$., 20 pages
- Published
- 2011
22. Formation of damascenone derived from glycosidically bound precursors in green tea infusions
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Emiko Kitayama, Peter Winterhalter, Satoshi Hirata, Tomomi Kinoshita, Ziyin Yang, Masayuki Suzuki, Susanne Baldermann, Peter Fleischmann, Shigetaka Matsumoto, and Naoharu Watanabe
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chemistry.chemical_classification ,Chemistry ,Chemical structure ,Glycoside ,Glycosidic bond ,General Medicine ,Food chemistry ,Damascenone ,Analytical Chemistry ,Hydrolysis ,chemistry.chemical_compound ,Aglycone ,Moiety ,Organic chemistry ,Food Science - Abstract
Damascenone is well-known for its potent flavour with an extremely low odour threshold. Several glycosidically bound precursors of damascenone have been isolated from several plants, but little is known about their occurrences in green tea infusions. In this work, three major glycosidic precursors of damascenone, 9-O-β- d -glucopyranosyl-megastigma-6,7-dien-3,5,9-triol (1a), 9-O-β- d -glucopyranosyl-3-hydroxy-7,8-didehydro-β-ionol (2a), and 3-O-β- d -glucopyranosyl-3-hydroxy-7,8-didehydro-β-ionol (2b) were isolated and identified in green tea infusions, and the stereochemistries at C-3 and C-9 positions of aglycone parts of the three glycosidic precursors were determined as (3S, 9R)-1a, (3R, 9R)-2a, and (3R, 9R)-2b, respectively. Compounds 1a, 2a, and 2b as well as 3-O-β- d -glucopyranosyl-megastigma-6,7-dien-3,5,9-triol (1b) were hydrolysed to form damascenone in a model system with strong acidic conditions (pH 2.0) and at high temperature (90 °C). In contrast to hydrolysis of 2a and 2b, more damascenone was transformed from 1a and 1b. Furthermore, the β- d -glucosyl moiety at the C-3 position gave a higher dehydration rate from megastigma-6,7-dien-3,5,9-triol to 3-hydroxy-7,8-didehydro-β-ionol than compound 1a carrying the sugar residue at C-9 position. Interestingly, the four glycosidic precursors of damascenone were not hydrolysed to give damascenone under slightly acidic conditions (pH 5.4 and 120 °C for 10 min), but they could be transformed to damascenone in the presence of green tea infusions even under the equal conditions.
- Published
- 2010
23. On the decomposition of rational functions
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Mohamed Ayad and Peter Fleischmann
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Discrete mathematics ,Algebra and Number Theory ,Magma (algebra) ,Rational function ,Indecomposability ,Partial fraction decomposition ,Combinatorics ,Computational Mathematics ,Polynomial and rational function modeling ,Bijection ,Elliptic rational functions ,Normal form of a rational function ,Indecomposable rational function ,Rational function decomposition ,Mathematics ,Variable (mathematics) - Abstract
Let f:=p/q∈K(x) be a rational function in one variable. By Lüroth’s theorem, the collection of intermediate fields K(f)⊊L⊊K(x) is in bijection with inequivalent proper decompositions f=g∘h, with g,h∈K(x) of degrees ≥2. In [Alonso, Cesar, Gutierrez, Jaime, Recio, Tomas, 1995. A rational function decomposition algorithm by near-separated polynomials. J. Symbolic Comput. 19, 527–544] an algorithm is presented to calculate such a function decomposition. In this paper we describe a simplification of this algorithm, avoiding expensive solutions of linear equations. A MAGMA implementation shows the efficiency of our method. We also prove some indecomposability criteria for rational functions, which were motivated by computational experiments.
- Published
- 2008
24. Application of high-speed counter-current chromatography for the isolation of 9′-cis-neoxanthin from fresh spinach
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Nils Köhler, Susanne Baldermann, Peter Fleischmann, and Annika Reinhard
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Solvent system ,chemistry.chemical_classification ,Ethanol ,Chromatography ,Molecular Structure ,biology ,Organic Chemistry ,Reproducibility of Results ,General Medicine ,Xanthophylls ,biology.organism_classification ,Biochemistry ,Analytical Chemistry ,Hexane ,chemistry.chemical_compound ,Countercurrent chromatography ,chemistry ,Spinacia oleracea ,Spinach ,Countercurrent Distribution ,Carotenoid ,9'-cis-neoxanthin - Abstract
Preparative HSCCC (high-speed counter-current chromatography) could be applied for the isolation of 9'-cis-neoxanthin from a crude carotenoid extract of fresh spinach leaves. The separation was performed on a Pharma-Tech Research Corp. CCC 1000 with a solvent system composed of hexane:ethanol:water at a volume ratio of 5:5:4.5 at a flow rate of 3 mL/min and at 850 rpm, using the lower phase as mobile phase. 9'-cis-neoxanthin with a purity of up to 94% could be obtained with a single HSCCC purification step of the crude carotenoid extract.
- Published
- 2007
25. Homomorphisms, localizations and a new algorithm to construct invariant rings of finite groups
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Peter Fleischmann, Chris F. Woodcock, and Gregor Kemper
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Discrete mathematics ,Finite group ,Algebra and Number Theory ,Polynomial ring ,Nuclear Theory ,Subalgebra ,Group order ,Field of fractions ,Computational algebra ,Modular invariant theory ,Homogeneous ,Localization ,Homomorphism ,Invariant (mathematics) ,Nuclear Experiment ,Algorithm ,Mathematics - Abstract
Let G be a finite group acting on a polynomial ring A over the field K and let A G denote the corresponding ring of invariants. Let B be the subalgebra of A G generated by all homogeneous elements of degree less than or equal to the group order | G | . Then in general B is not equal to A G if the characteristic of K divides | G | . However we prove that the field of fractions Quot ( B ) coincides with the field of invariants Quot ( A G ) = Quot ( A ) G . We also study various localizations and homomorphisms of modular invariant rings as tools to construct generators for A G . We prove that there is always a nonzero transfer c ∈ A G of degree | G | , such that the localization ( A G ) c can be generated by fractions of homogeneous invariants of degrees less than 2 ⋅ | G | − 1 . If A = Sym ( V ⊕ F G ) with finite-dimensional F G -module V, then c can be chosen in degree one and 2 ⋅ | G | − 1 can be replaced by | G | . Let N denote the image of the classical Noether-homomorphism (see the definition in the paper). We prove that N contains the transfer ideal and thus can be used to calculate generators for A G by standard elimination techniques using Grobner-bases. This provides a new construction algorithm for A G .
- Published
- 2007
26. Modular group actions on algebras and p-local Galois extensions for finite groups
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Peter Fleischmann and Chris F. Woodcock
- Subjects
Discrete mathematics ,Finite group ,Pure mathematics ,Algebra and Number Theory ,G-module ,Cyclic group ,QA150 ,Matrix group ,QA171 ,Field extension ,Symmetric group ,16R30, 20G05, 13A50 ,FOS: Mathematics ,Representation Theory (math.RT) ,Abelian group ,Mathematics - Representation Theory ,Mathematics ,Group ring - Abstract
Let k be a field of positive characteristic p and let G be a finite group. In this paper we study the category TsG of finitely generated commutative k-algebras A on which G acts by algebra automorphisms with surjective trace. If A = k[X], the ring of regular functions of a variety X, then trace-surjective group actions on A are characterized geometrically by the fact that all point stabilizers on X are p'-subgroups or, equivalently, that A is a Galois extension of the ring of P invariants for every Sylow p-group P of G. We investigate categorical properties, using a version of Frobenius-reciprocity for group actions on k-algebras, which is based on tensor induction for modules. We also describe projective generators in TsG , extending and generalizing the investigations started in [8], [7] and [9] in the case of p-groups. As an application we show that for an abelian or p-elementary group G and k large enough, there is always a faithful (possibly nonlinear) action on a polynomial ring such that the ring of invariants is also a polynomial ring. This would be false for linear group actions by a result of Serre. For p-solvable groups we obtain a structure theorem on trace-surjective algebras, generalizing the corresponding result for p-groups in [8]., 23 pages, accepted by J. of Algebra
- Published
- 2015
27. Geheime Aktenvernichtungen vor dem 'Einmarsch der Besetzungsmacht' 1945 im bayerischen Regierungsbezirk Schwaben
- Author
-
Peter Fleischmann
- Subjects
Computer Networks and Communications ,Hardware and Architecture ,Software - Published
- 2006
28. Enzymatic carotenoid degradation and aroma formation in nectarines (Prunus persica)
- Author
-
Peter Fleischmann, Susanne Baldermann, and Michael Naim
- Subjects
chemistry.chemical_classification ,biology ,Carotenoid oxygenase ,Ripening ,biology.organism_classification ,Norisoprenoids ,Averrhoa carambola ,Biochemistry ,chemistry ,Chromoplast ,biology.protein ,Food science ,Carotenoid ,Flavor ,Aroma ,Food Science - Abstract
C-13 norisoprenoids such as β-ionone, 3 hydroxy-β-ionone, and 3 hydroxy-5,6-epoxy-β-ionone are important carotenoid related aroma compounds in fruits. Apart from chemical degradation (photo-oxygenation, (auto)oxidation, thermal degradation), enzymatic cleavage is an important flavor formation pathway [ Enzell, C. (1985) . Biodegradation of carotenoids – an important route to aroma compounds. Pure and Applied Chemistry, 57(5), 693–700; Winterhalter, P., & Rouseff, R. (Eds.). (2001) . Carotenoid-derived aroma compounds. ACS symposium series 802, Washington, DC: American Chemical Society (ISBN 0-8412-3729-8)]. In nectarines, the content of carotenoid degradation products depends on the degree of maturity. In fully ripened fruit up to 40% of the aglycons are C-13 norisoprenoids [Aubert, C., Gunata, Z., Ambid, C., & Baumes, R. (2003). Changes in physicochemical characteristics and volatile constituents of yellow- and white-fleshed nectarines during maturation and artificial ripening. Journal of Agriculture and Food Chemistry, 51(10), 3083–3091]. Regiospecific carotenoid cleavage enzymes have been shown to be involved in aroma formation in different plants and fruits [Bouvier, F., Suire, C., Mutterer, J., & Camara, B. (2003). Oxidative remodeling of chromoplast carotenoids: identification of the carotenoid dioxygenase CsCCD and CsZCD genes involved in crocus secondary metabolite biogenesis. Plant Cell, 15(1), 47–62; Fleischmann, P., Studer, K., & Winterhalter, P., (2002). Partial purification and kinetic characterization of a carotenoid cleavage enzyme from quince fruit (Cydonia oblonga). Journal of Agriculture and Food Chemistry, 50(6), 1677–1680; Fleischmann, P., Watanabe, N., & Winterhalter, P., (2003). Enzymatic carotenoid cleavage in star fruit (Averrhoa carambola). Phytochemistry, 63(2), 131–137; Schwartz, Qin & Zeevaart, 2001 ]. This paper describes the isolation and partial characterization of carotenoid cleavage enzymes in nectarines, isolated from ripe skin of commercially available fruit. The enzyme is characterized by its kinetic parameters (vmax, Km, time constant, temperature dependence, activation energy).
- Published
- 2005
29. Depth and cohomological connectivity in modular invariant theory
- Author
-
Peter Fleischmann, R. James Shank, and Gregor Kemper
- Subjects
Combinatorics ,Symmetric algebra ,Finite group ,Integer ,Applied Mathematics ,General Mathematics ,Cyclic group ,Nilpotent group ,Upper and lower bounds ,Invariant theory ,Group representation ,Mathematics - Abstract
the cohomological connectivity of the symmetric algebra S(V ) to be the smallest positive integer m such that H m (G;S(V ))6 0. We show that min dimK(V P ) +m + 1; dimK(V ) is a lower bound for the depth of S(V ) G . We characterize those representations for which the lower bound is sharp and give several examples of representations satisfying the criterion. In particular, we show that if G is p-nilpotent and P is cyclic then, for any modular representation, the depth of S(V ) G is min dimK(V P ) + 2; dimK(V ) .
- Published
- 2004
30. On the Depth of Cohomology Modules
- Author
-
R. James Shank, Peter Fleischmann, and Gregor Kemper
- Subjects
Symmetric algebra ,Discrete mathematics ,Ring (mathematics) ,Transfer (group theory) ,General Mathematics ,Image (category theory) ,Cohomology ,Vector space ,Mathematics - Abstract
We study the cohomology modules H i (G;R) of a p-group G acting on a ring R of characteristic p, for i > 0. In particular, we are interested in the Cohen-Macaulay property and the depth of H i (G;R) regarded as an R G -module. We rst determine the support of H i (G;R), which turns out to be independent of i. Then we study the Cohen-Macaulay property for H 1 (G;R). Further results are restricted to the special case that G is cyclic and R is the symmetric algebra of a vector space on which G acts. We determine the depth of H i (G;R) for i odd and obtain results in certain cases for i even. Along the way, we determine the degrees in which the transfer map Tr G :R! R G has non-zero image.
- Published
- 2004
31. Carotenoid Cleavage Products
- Author
-
Peter Winterhalter, Susan E. Ebeler, Wilfried Schwab, Fong-Chin Huang, Péter Molnár, A. Ohmiya, Rachel E. Kopec, Steven J. Schwartz, Ana M. Sánchez, Susanne Baldermann, Masaya Kato, Akira Fujita, Peter Fleischmann, Naoharu Watanabe, Masayoshi Yamamoto, Ziyin Yang, Tatsuya Kawahashi, Kazuyoshi Kuwano, H. Dietrich, M. Hey, C. Patz, P. Kürbel, B. Froehling, Ziya Günata, Imelda Ryona, Gavin L. Sacks, Recep Gök, P. Guedes de Pinho, R. C. Martins, M. A. Vivier, P. R. Young, C. M. Oliveira, A. C. Silva Ferreira, K. Schmidt, K. Kunkel, R. Szweda, A. Portz, M. A. Fraatz, H. Zorn, Christoph Nacke, Martin Schilling, M. M. W. Etschmann, Jens Schrader, Maria M. W. Etschmann, Robert Walisko, Michel Carail, Pascale Goupy, Eric Reynaud, Olivier Dangles, Catherine Caris-Veyrat, Elisabet Fernández-García, José J. Ríos, Manuel Jarén-Galán, Antonio Pérez-Gálvez, Chamila Nimalaratne, Jianping Wu, Andreas Schieber, Peter Winterhalter, Susan E. Ebeler, Wilfried Schwab, Fong-Chin Huang, Péter Molnár, A. Ohmiya, Rachel E. Kopec, Steven J. Schwartz, Ana M. Sánchez, Susanne Baldermann, Masaya Kato, Akira Fujita, Peter Fleischmann, Naoharu Watanabe, Masayoshi Yamamoto, Ziyin Yang, Tatsuya Kawahashi, Kazuyoshi Kuwano, H. Dietrich, M. Hey, C. Patz, P. Kürbel, B. Froehling, Ziya Günata, Imelda Ryona, Gavin L. Sacks, Recep Gök, P. Guedes de Pinho, R. C. Martins, M. A. Vivier, P. R. Young, C. M. Oliveira, A. C. Silva Ferreira, K. Schmidt, K. Kunkel, R. Szweda, A. Portz, M. A. Fraatz, H. Zorn, Christoph Nacke, Martin Schilling, M. M. W. Etschmann, Jens Schrader, Maria M. W. Etschmann, Robert Walisko, Michel Carail, Pascale Goupy, Eric Reynaud, Olivier Dangles, Catherine Caris-Veyrat, Elisabet Fernández-García, José J. Ríos, Manuel Jarén-Galán, Antonio Pérez-Gálvez, Chamila Nimalaratne, Jianping Wu, and Andreas Schieber
- Subjects
- Metabolites--Congresses, Carotenoids--Metabolism--Congresses, Carotenoids--Analysis--Congresses, Oxygenases--Congresses, Food--Analysis--Congresses, Enzymes--Congresses
- Published
- 2013
32. Organization
- Author
-
Peter Fleischmann, Kyung Min Kim, and Seong-Gu Hwang
- Subjects
General Medicine - Published
- 2016
- Full Text
- View/download PDF
33. The relative trace ideal and the depth of modular rings of invariants
- Author
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R. J. Shank and Peter Fleischmann
- Subjects
Ring (mathematics) ,Pure mathematics ,Ideal (set theory) ,Trace (linear algebra) ,Mathematics::Commutative Algebra ,business.industry ,General Mathematics ,Mathematics::Rings and Algebras ,Modular design ,Dimension (vector space) ,Fixed-point space ,Representation (mathematics) ,business ,Mathematics - Abstract
We prove that for a modular representation, the depth of the ring of invariants is the sum of the dimension of the fixed point space of the p-Sylow subgroup and the grade of the relative trace ideal. We also determine which of the Dickson invariants lie in the radical of the relative trace ideal and we describe how to use the Dickson invariants to compute the grade of the relative trace ideal.
- Published
- 2003
34. Enzymatic carotenoid cleavage in star fruit (Averrhoa carambola)
- Author
-
Peter Winterhalter, Naoharu Watanabe, and Peter Fleischmann
- Subjects
Chromatography, Gas ,Plant Science ,Horticulture ,Biochemistry ,Michaelis–Menten kinetics ,Averrhoa carambola ,chemistry.chemical_compound ,Sodium dodecyl sulfate ,Rosaceae ,Molecular Biology ,Polyacrylamide gel electrophoresis ,chemistry.chemical_classification ,Chromatography ,biology ,Terpenes ,Chemistry ,Isoelectric focusing ,Temperature ,Substrate (chemistry) ,General Medicine ,beta Carotene ,biology.organism_classification ,Carotenoids ,Enzyme assay ,Kinetics ,Enzyme ,Spectrophotometry ,Fruit ,biology.protein ,Electrophoresis, Polyacrylamide Gel ,Isoelectric Focusing ,Norisoprenoids ,Oxidation-Reduction - Abstract
This paper presents the first description of an enzyme fraction exhibiting carotenoid cleavage activity isolated from fruit skin of Averrhoa carambola. Partial purification of the enzyme could be achieved by acetone precipitation, ultrafiltration (300 kDa, 50 kDa), isoelectric focusing (pH 3-10) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (7.5%). In this way, an enzymatically active protein fraction was obtained, consisting of four proteins in the molecular weight range of between 12 and 90 kDa. Using beta-carotene as substrate, the enzyme activity was detected spectrophotometrically at 505 nm. The main reaction product, detected by GC analysis, was beta-ionone. This proves that the isolated enzymes are closely related to aroma metabolism and release of star fruit. The time constant of the reaction was 16.6 min, the Michaelis Constant K(m)=3.6 micromol 1(-1) and the maximum velocity V(max)=10.5 x 10(-3) micromol l(-1) s(-1) mg((Protein))(-1). The optimum temperature was 45 degrees C.
- Published
- 2003
35. The black-box Niederreiter algorithm and its implementation over the binary field
- Author
-
Peter Roelse, Peter Fleischmann, Markus Chr. Holder, Discrete Mathematics, and Coding Theory and Cryptology
- Subjects
Algebra and Number Theory ,Computational complexity theory ,Applied Mathematics ,Field (mathematics) ,Computational Mathematics ,Matrix (mathematics) ,symbols.namesake ,Finite field ,Factorization ,Gaussian elimination ,Factorization of polynomials ,Linear algebra ,symbols ,Algorithm ,Mathematics - Abstract
The most time-consuming part of the Niederreiter algorithm for factoring univariate polynomials over finite fields is the computation of elements of the nullspace of a certain matrix. This paper describes the so-called ``black-box'' Niederreiter algorithm, in which these elements are found by using a method developed by Wiedemann. The main advantages over an approach based on Gaussian elimination are that the matrix does not have to be stored in memory and that the computational complexity of this approach is lower. The black-box Niederreiter algorithm for factoring polynomials over the binary field was implemented in the C programming language, and benchmarks for factoring high-degree polynomials over this field are presented. These benchmarks include timings for both a sequential implementation and a parallel implementation running on a small cluster of workstations. In addition, the Wan algorithm, which was recently introduced, is described, and connections between (implementation aspects of) Wan's and Niederreiter's algorithm are given.
- Published
- 2003
36. Double Ordering and Fill-In for the LU Factorization
- Author
-
Otto Mutzbauer, Markus Baumann, and Peter Fleischmann
- Subjects
Combinatorics ,Matrix (mathematics) ,Degree (graph theory) ,law ,Incomplete LU factorization ,Analysis ,Column (data store) ,LU decomposition ,Sparse matrix ,law.invention ,Mathematics - Abstract
We present a new method, called reversed double ordering, for reordering arbitrary matrices prior to LU factorization. This reordering creates a variable-band matrix. We compare the fill-in of the LU factorization for sparse matrices with respect to reversed double ordering, column minimum degree ordering, and the reversed Cuthill--McKee algorithm. Moreover, we combine the first two reorderings with good success.
- Published
- 2003
37. Identification of (3S, 9R)- and (3S, 9S)-Megastigma-6,7-dien-3,5,9-triol 9-O-β-<scp>D</scp>-glucopyranosides as Damascenone Progenitors in the…
- Author
-
Kazuteru Takagi, Peter Winterhalter, Masaya Mizoguchi, Yumiko Yamano, Masayoshi Ito, Tetuichiro Morita, Satoshi Hirata, Naoharu Watanabe, Masayuki Suzuki, Peter Fleischmann, Ikue Hashimoto, and Shigetaka Matsumoto
- Subjects
biology ,Stereochemistry ,Organic Chemistry ,General Medicine ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Biochemistry ,Damascenone ,Analytical Chemistry ,law.invention ,Rosa × damascena ,Steam distillation ,chemistry.chemical_compound ,chemistry ,law ,Organic chemistry ,Triol ,Progenitor cell ,Molecular Biology ,Essential oil ,Aroma ,Biotechnology - Abstract
The progenitors of damascenone (1), the most intensive C13-norisoprenoid volatile aroma constituent of rose essential oil, were surveyed in the flowers of Rosa damascena Mill. Besides 9-O-β-D-glucopyranosyl-3-hydroxy-7,8-didehydro-β-ionol (4b), a stable progenitor already isolated from the residual water after steam distillation of flowers of R. damascena Mill., two labile progenitors were identified to be (3S, 9R)- and (3S, 9S)-megastigma-6,7-dien-3,5,9-triol 9-O-β-D-glucopyranosides (2b) based on their synthesis and HPLC-MS analytical data. Compound 2b gave damascenone (1), 3-hydroxy-β-damascone (3) and 4b upon heating under acidic conditions.
- Published
- 2002
38. Multitronic — Das neue Automatikgetriebe von Audi
- Author
-
Peter Franzen, Thorsten Gleich, Georg Hommes, Klaus Nowatschin, Horst Wild, Hans-Peter Fleischmann, Oswald Friedmann, and Hartmut Faust
- Subjects
Engineering ,business.industry ,Automotive Engineering ,business ,Humanities - Abstract
Mit der multitronic vereint Audi den Komfort heutiger Automatikgetriebe mit der Dynamik und der Wirtschaftlichkeit manueller Schaltgetriebe. Teil 1 befasste sich mit dem Getriebekonzept, der vorliegende Teil 2 beschreibt die Steuerung und Regelung des Getriebes.
- Published
- 2000
39. multitronic — Das neue Automatikgetriebe von Audi
- Author
-
Thorsten Gleich, Klaus Nowatschin, Georg Hommes, Horst Wild, Hans-Peter Fleischmann, Oswald Friedmann, Hartmut Faust, and Peter Franzen
- Subjects
Computer science ,Automotive Engineering - Published
- 2000
40. On degree bounds for invariant rings of finite groups over finite fields
- Author
-
Peter Fleischmann and Wolfgang Lempken
- Published
- 1999
41. Squarefree Polynomials over Finite Fields and Regular Semisimple Classes of Certain Classical Groups
- Author
-
Peter Fleischmann
- Subjects
Classical group ,Discrete mathematics ,Conjugacy class ,Finite field ,Algebra and Number Theory ,Applied Mathematics ,Lie algebra ,General Engineering ,Square-free integer ,Abelian group ,Engineering(all) ,Mathematics ,Theoretical Computer Science - Abstract
LetGbePSLn(q),PSUn(q),Sp2n(q) orPSp2n(q), whereqis a power of the primep. Using results on the numbers of special squarefree polynomials over finite fields, we describe and count the conjugacy classes ofp′-elements with abelian centralizers inG. Similar results are obtained for the semisimple orbits ofGon the corresponding finite Lie algebras.
- Published
- 1998
- Full Text
- View/download PDF
42. The primitive $p$-Frobenius groups
- Author
-
Peter Fleischmann, W. Lempken, and Pham Huu Tiep
- Subjects
Applied Mathematics ,General Mathematics ,Mathematics - Published
- 1998
43. A new degree bound for vector invariants of symmetric groups
- Author
-
Peter Fleischmann
- Subjects
Combinatorics ,Symmetric algebra ,Ring (mathematics) ,Degree (graph theory) ,Symmetric group ,Direct sum ,Applied Mathematics ,General Mathematics ,Elementary symmetric polynomial ,Commutative ring ,Ring of symmetric functions ,Mathematics - Abstract
Let R R be a commutative ring, V V a finitely generated free R R -module and G ≤ G L R ( V ) G\le GL_R(V) a finite group acting naturally on the graded symmetric algebra A = S ( V ) A=S(V) . Let β ( V , G ) \beta (V,G) denote the minimal number m m , such that the ring A G A^G of invariants can be generated by finitely many elements of degree at most m m . For G = Σ n G=\Sigma _n and V ( n , k ) V(n,k) , the k k -fold direct sum of the natural permutation module, one knows that β ( V ( n , k ) , Σ n ) ≤ n \beta (V(n,k),\Sigma _n) \le n , provided that n ! n! is invertible in R R . This was used by E. Noether to prove β ( V , G ) ≤ | G | \beta (V,G) \le |G| if | G | ! ∈ R ∗ |G|! \in R^* . In this paper we prove β ( V ( n , k ) , Σ n ) ≤ m a x { n , k ( n − 1 ) } \beta (V(n,k),\Sigma _n) \le max\{n,k(n-1)\} for arbitrary commutative rings R R and show equality for n = p s n=p^s a prime power and R = Z R = \mathbb {Z} or any ring with n ⋅ 1 R = 0 n\cdot 1_R=0 . Our results imply β ( V , G ) ≤ m a x { | G | , rank ( V ) ( | G | − 1 ) } \begin{equation*} \beta (V,G)\le max\{|G|, \operatorname {rank}(V)(|G|-1)\}\end{equation*} for any ring with | G | ∈ R ∗ |G| \in R^* .
- Published
- 1998
44. On Generators of Modular Invariant Rings of Finite Groups
- Author
-
W. Lempken and Peter Fleischmann
- Subjects
Algebra ,business.industry ,General Mathematics ,Invariant (mathematics) ,Modular design ,business ,Mathematics - Published
- 1997
45. Polynomial identities for orbit numbers of general linear and unitary groups over finite fields
- Author
-
Peter Fleischmann
- Subjects
Discrete mathematics ,Numerical Analysis ,Sequence ,Polynomial ,Algebra and Number Theory ,Combinatorics ,Identity (mathematics) ,Conjugacy class ,Finite field ,Lie algebra ,Discrete Mathematics and Combinatorics ,Geometry and Topology ,Orbit (control theory) ,Element (category theory) ,Mathematics - Abstract
Let p(n) be the set of all partitions of n ϵ N and denote an element c = 1c12c2 … ncn ϵ p(n) by the sequence (c1, c2, … cn) ϵ Nn0 with ∑i = 1,…nci · i = n. For n ϵ N and ∈ ϵ {0, ± 1} we define F n, ϵ (X)≔ Σ (c k )ϵP(n) Π (k=1,…,c k > 0) X c k −1 ·(X−ϵ) . Then fn, ∈(q) equals the number of conjugacy classes in GLn(q) or Un(q2) for ∈ = 1 or −1 respectively or the number of adjoint GLn(q)- or Un(q2)-orbits on their finite Lie algebras, if ∈ = 0. In this paper we give a unified proof of this together with a polynomial identity for fn, ∈(X), involving partitions and ‘multipartitions’ of n.
- Published
- 1997
46. Finitep′-Semiregular Groups
- Author
-
Pham Huu Tiep, Wolfgang Lempken, and Peter Fleischmann
- Subjects
Pure mathematics ,Algebra and Number Theory ,Mathematics - Published
- 1997
47. Biodegradation of Carotenoids - An Important Route to Scent Formation
- Author
-
Akira Fujita, Masaya Kato, Peter Fleischmann, Naoharu Watanabe, Susanne Baldermann, and Peter Winterhalter
- Subjects
chemistry.chemical_classification ,chemistry ,Environmental chemistry ,Biodegradation ,Carotenoid - Published
- 2013
48. On the computation of conjugacy classes of Chevalley groups
- Author
-
Ingo Janiszczak and Peter Fleischmann
- Subjects
Algebra ,Mathematics::Group Theory ,Algebra and Number Theory ,Conjugacy class ,Mathematics::Quantum Algebra ,Applied Mathematics ,Computation ,Mathematics::Rings and Algebras ,Theory of computation ,Type (model theory) ,Mathematics::Representation Theory ,Mathematics - Abstract
In this paper an algorithm is presented to determine the number of semisimple conjugacy classes for a given centralizertype for the Chevalley groupsSLn(q) andSUn(q). Moreover we give the exact number of regular semisimple classes of this groups and a summary of results on the generic classnumber of exceptional Chevalley groups of adjoint type.
- Published
- 1996
49. Influence of exogenously applied abscisic acid on carotenoid content and water uptake in flowers of the tea plant (Camellia sinensis)
- Author
-
Susanne, Baldermann, Ziyin, Yang, Miwa, Sakai, Peter, Fleischmann, Akio, Morita, Yasushi, Todoroki, and Naoharu, Watanabe
- Subjects
Plant Growth Regulators ,Tea ,Plant Development ,Water ,Flowers ,Xanthophylls ,beta Carotene ,Carotenoids ,Camellia sinensis ,Abscisic Acid - Abstract
Carotenoids are a major class of plant pigments and fulfill many functions in different organisms that either produce or consume them. Although the color of the stamina of tea (Camellia sinensis) flowers is clearly due to the presence of carotenoids, the carotenoid profile and content remain to be discovered.We investigated the carotenoid profile of tea flowers and determined changes in concentrations over the floral development. The flowers contained oxygenated xanthophylls such as neoxanthin, lutein and zeaxanthin, as well as the hydrocarbons β-carotene and α-carotene. Flowers of the tea plant contain to vegetables comparable amounts of carotenoids. The content of 9'-cis-epoxycarotenoids, which serve as abscisic acid precursors, as well as changes in concentration of abscisic acid were studied. The concentrations of carotenoids decreased whereas the abscisic acid content increased over the floral development. Exogenously applied S-abscisic acid affected water uptake, flower opening and carotenoid accumulation.In summary, this paper reports, for the first time, the carotenoid profile and content of tea flowers. The study revealed that carotenoids in tea flowers are an interesting target in respect of possible applications of tea flower extracts as well as biological functions of abscisic acid during floral development.
- Published
- 2012
50. Biosynthesis of α- and β-ionone, prominent scent compounds, in flowers of Osmanthus fragrans
- Author
-
Naoharu Watanabe, Masaya Kato, Peter Fleischmann, and Susanne Baldermann
- Subjects
chemistry.chemical_classification ,biology ,Chemistry ,Oleaceae ,Plant composition ,Osmanthus fragrans ,Flowers ,alpha-Carotene ,biology.organism_classification ,Ionone ,Carotenoids ,General Biochemistry, Genetics and Molecular Biology ,Carotenoid cleavage dioxygenase 1 ,chemistry.chemical_compound ,Biosynthesis ,beta-Carotene ,Odorants ,Botany ,Norisoprenoids ,Carotenoid - Abstract
Carotenoid derived volatiles are important fragrance compounds, which contribute to the scents of flowers from diverse taxa. A famous example is represented by the flowers of Osmanthus fragrans where apocarotenoids account for more than 20% of all volatiles. In the recent years, bio-degradation of carotenoids has been shown to be an important route for apocarotenoids formation. Here, we report on the contribution the O. fragrans carotenoid cleavage dioxygenase 1 to the synthesis of the two predominant C(13)-apocarotenoids, α- and β-ionone, derived from α-and β-carotene, respectively.
- Published
- 2012
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