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„Egipcios por doquier“
(2002)
La „visión orientalista“ de Alejandro de Humboldt es un simple término para designar un modo complejo de percepción y descripción empleado por el científico alemán en su relación de viaje. Humboldt „orientaliza“ a América por medio de numerosas metáforas estereotipadas, de comparaciones científicas y analogías económico-coloniales, y perpetúa a su vez un „Orientalismo“ filológico como el que ha analizado Edward Said. Sin embargo, de manera gradual, la crítica autorreflexiva y una serie de sutiles inversiones erosionan las oposiciones binarias y las construcciones coloniales. El texto de Humboldt emplea primeramente patrones eurocentristas para luego deconstruirlos. Lo que en un principio aparece como un síntoma, pasa luego a desestabilizar estratégicamente el concepto del „Oriente“ como paradigma de la diferencia cultural y el „Orientalismo“ como discurso imperial.
A number of special purpose vessels in the world carried or carry the name of Alexander von Humboldt, who had substantial interests in oceanography. However, most of his marine texts are scattered over his major works, and he never finished his manuscript on ocean circulation. But there is a general agreement that A. v. Humboldt was one of the pioneers of marine sciences. He made his own observations on the sailing vessels he used on his expedition to the Neotropics, mainly concerning sea surface temperatures. In 2002 there was a discussion in Germany about the name of a new research vessel which is going to be commissioned in the summer of 2004. It was suggested by the science community to take the name of „Alexander von Humboldt“ again, as the new vessel is replacing a medium-sized ship with this name operated now by the Baltic Sea Research Institute in Rostock-Warnemünde. This vessel has been in service from 1970 to 1990 for the Academy of Sciences of the former German Democratic Republic. The first German research vessel „Alexander von Humboldt“ was a fishing trawler (1939). Furthermore, Peru and Mexico operate research vessels bearing Humboldt’s name. The best known „Alexander von Humboldt“ is an ocean going sailing ship of the International Sail Training Association, based in Bremen. She is engaged in educational programmes and went the South America in 1999 following Humboldt’s route. Thus, Humboldt’s marine legacy is preserved. The proposal to use the undisputed name of this great all-round scientist for the new German vessel under construction now was not successful. A high-ranking jury decided to prefer “Maria Sibylla Merian” (1647-1717), which was suggested by a young student in a nation-wide competition to find a name. As Humboldt 100 years later, she went to South America to study plants and other fields of natural history.
Der Beitrag stellt das Konzept „alltägliche Lebensführung“ in den Kontext aktueller erwachsenenpädagogischer Diskussionen. Erstens wird der Frage nachgegangen, warum die Erwachsenenpädagogik ein Interesse am Lebensführungskonzept haben kann. Dieses Interesse ist an die Erwartung gebunden, mehr über das alltägliche, nichtinstitutionalisierte Lernen von Erwachsenen zu erfahren. Zweitens wird dargelegt, wie das Konzept der alltäglichen Lebensführung durch eine subjektwissenschaftliche Erwach-senenpädagogik eine Ergänzung erfahren könnte. Dies betrifft insbesondere die lernende Veränderung bzw. die Veränderungsfähigkeit alltäglicher Lebensführungsregeln. Mit anderen Worten: die Erwachsenenpädagogik kann ihrerseits einen Beitrag zum Lebensführungskonzept leisten.
On the occasion of his farewell lecture, Manfred Mols looks back to his academic work of the last four decades, and discusses the essential meaning of area studies. He tries to clarify the important denotation of institutes for regional researchers. Area studies should help us to understand changing processes in international policies and they do. He underlines his critical point of view with the position and treatment of area studies among certain universities in Germany.
In this paper, we discuss the viscosity solutions of the weakly coupled systems of fully nonlinear second order degenerate parabolic equations and their Cauchy-Dirichlet problem. We prove the existence, uniqueness and continuity of viscosity solution by combining Perron's method with the technique of coupled solutions. The results here generalize those in [2] and [3].
rezensiertes Werk: Verlag Zeit-Fragen (Hrsg.): Das Rote Kreuz oder Kubismus Allüren? Zur überflüssigen Debatte um ein neues Rotkreuz-Symbol und zur Neutralität als Voraussetzung („Conditio sine qua non") für humanitäre Hilfeleistung im Krieg, Sonderdruck aus der Wochenzeitung Zeit-Fragen. Sonderdruck aus der Wochenzeitung Zeit-Fragen. - Zürich : 2002. - 60 S.
Inhalt: Joachim Scheiner: Die Angst der Geographie vor dem Raum 1 Verkehrswissenschaftliche Raumversessenheit und geographische Raumvergessenheit 1.1 Verkehrswissenschaftliche Diskussion 1.2 Sozialgeographische Diskussion 2 Verkehrshandeln – raumstrukturell erzwungen oder Ergebnis freier Entscheidung? 2.1 Raumontologie oder Empirie? 2.2 Darstellung der Vorgehensweise Bahrenbergs 3 Fazit Gerhard Bahrenberg: Space matters? Ja, aber welcher 'Raum", wofür, wie und wieviel! 1 Eine chorologische Perspektive und ihre Konsequenzen 2 Zur Kritk Scheiners 2.1 Handwerkliche Fragen 2.2 Methodologie, Theorie und Interpretation der Ergebnisse 3 Zum Dilemma einer raumzentrierten Verkehrsplanung
Un sabio en la meseta
(2002)
Presentamos el artículo publicado en la revista alemana Hertha en 1825, donde Alexander von Humboldt comentó su viaje por España y el estudio geográfico de la meseta, con una introducción a modo de ensayo, que sitúa el viaje español de Humboldt en su contexto. La argumentación científica es precisa, se dan las nivelaciones barométricas y se ofrece el perfil topográfico peninsular, lo que nos ha hecho considerar la necesidad de la traducción al español de este trabajo de Alejandro de Humboldt titulado Sobre la configuración y el clima de la meseta de la Península Ibérica (Über die Gestalt und das Klima des Hochlandes in der iberischen Halbinsel). La forma de presentación de Humboldt de sus investigaciones en la Península es bastante curiosa, ya que a pesar del tono estrictamente científico de su escrito, guía al lector a través de una carta a su editor el profesor Berghaus, con la intercalación de notas de su Diario y con datos obtenidos de sus corresponsales españoles.
Umweltdaten aus Brandenburg
(2002)
We study an elliptic differential operator on a manifold with conical singularities, acting as an unbounded operator on a weighted Lp-space. Under suitable conditions we show that the resolvent (λ - A )-¹ exists in a sector of the complex plane and decays like 1/|λ| as |λ| -> ∞. Moreover, we determine the structure of the resolvent with enough precision to guarantee existence and boundedness of imaginary powers of A. As an application we treat the Laplace-Beltrami operator for a metric with striaght conical degeneracy and establish maximal regularity for the Cauchy problem u - Δu = f, u(0) = 0.
Tagungsbericht
(2002)
Rezensiertes Werk: Söldnerleben am Vorabend des Dreißigjährigen Krieges : Lebenslauf und Kriegstagebuch 1617 des hessischen Obristen Caspar von Widmarckter / hrsg. und bearb. von Holger Th. Gräf. Mit Beitr. von Sven Externbrink und Ralf Pröve. - Marburg an der Lahn : Trautvetter & Fischer, 2000. - 168 S. : Ill., graph. Darst., Kt. - (Beiträge zur hessischen Geschichte ; 16) ISBN 3-87822-113-4
Söldner aus Böhmen
(2002)
We prove a theorem describing the behaviour of the relative index of families of Fredholm operators under surgery performed on spaces where the operators act. In connection with additional conditions (like symmetry conditions) this theorem results in index formulas for given operator families. By way of an example, we give an application to index theory of families of boundary value problems.
An approach to the development of fluorescent probes to follow polymerizations in situ using fluorinated cross-conjugated enediynes (Y-enynes) is reported. Different substitution patterns in the Y-enynes result in distinct solvatochromic behavior. β,β-Bis(phenylethynyl)pentafluorostyrene 7, which bears no donor substituents and only fluorine at the styrene moiety, shows no solvatochromism. Donor substituted β,β-bis(3,4,5-trimethoxyphenylethynyl) pentafluorostyrene 8 and β,β-bis(4-butyl-2,3,5,6-tetrafluorophenylethynyl)-3,4,5-trimethoxystyrene 9 exhibit solvatochromism upon change of solvent polarity. Y-enyne 8 showed the largest solvatochromic shift (94 nm bathochromic shift) upon changing solvent from cyclohexane to acetonitrile. A smaller solvatochromic response (44 nm bathochromic shift) was observed for 9. Lippert–Mataga treatment of 8 and 9 yields slopes of -10,800 and -6,400 cm -1, respectively. This corresponds to a change in dipole moment of 9.6 and 6.9 D, respectively. The solvatochromic behavior in 8 and 9 supports the formation of an intramolecular charge transfer (ICT) state. The low fluorescence quantum yields are caused by competitive double bond rotation. The fluorescence decay time of 9 decreases in methyltetrahydrofuran from 2.1 ns at 77 K to 0.11 ns at 200 K. Efficient single bond rotation in 9 was frozen at -50 °C in a configuration in which the trimethoxyphenyl ring is perpendicular to the fluorinated rings. 7–9 are photostable compounds. The X-ray structure of 7 shows it is not planar and that its conjugation is distorted. Y-enyne 7 stacks in the solid state showing coulombic, actetylene–arene, and fluorine–π interactions.
Significant seasonal variation in size at settlement has been observed in newly settled larvae of Dreissena polymorpha in Lake Constance. Diet quality, which varies temporally and spatially in freshwater habitats, has been suggested as a significant factor influencing life history and development of freshwater invertebrates. Accordingly, experiments were conducted with field-collected larvae to test the hypothesis that diet quality can determine planktonic larval growth rates, size at settlement and subsequent post-metamorphic growth rates. Larvae were fed one of two diets or starved. One diet was composed of cyanobacterial cells which are deficient in polyunsaturated fatty acids (PUFAs), and the other was a mixed diet rich in PUFAs. Freshly metamorphosed animals from the starvation treatment had a carbon content per individual 70% lower than that of larvae fed the mixed diet. This apparent exhaustion of larval internal reserves resulted in a 50% reduction of the postmetamorphic growth rates. Growth was also reduced in animals previously fed the cyanobacterial diet. Hence, low food quantity or low food quality during the larval stage of D. polymorpha lead to irreversible effects for postmetamorphic animals, and is related to inferior competitive abilities.
Steady-state and time-resolved fluorescence methods were applied to investigate the fluorescence properties of humic substances of different origins. Using standard 2D emission and total luminescence spectra, fluorescence maxima, the width of the fluorescence band and a relative fluorescence quantum efficiency were determined. Different trends for fulvic acids and humic acids were observed indicating differences in the heterogeneity of the sample fractions. The complexity of the fluorescence decay of humic substances is discussed and compared to simple model compounds. The effect of oxidation of humic substances on their fluorescence properties is discussed as well.
Soldaten nach Amerika
(2002)
Relative elliptic theory
(2002)
This paper is a survey of relative elliptic theory (i.e. elliptic theory in the category of smooth embeddings), closely related to the Sobolev problem, first studied by Sternin in the 1960s. We consider both analytic aspects to the theory (the structure of the algebra of morphismus, ellipticity, Fredholm property) and topological aspects (index formulas and Riemann-Roch theorems). We also study the algebra of Green operators arising as a subalgebra of the algebra of morphisms.
Given an algebra of pseudo-differential operators on a manifold, an elliptic element is said to be a reduction of orders, if it induces isomorphisms of Sobolev spaces with a corresponding shift of smoothness. Reductions of orders on a manifold with boundary refer to boundary value problems. We consider smooth symbols and ellipticity without additional boundary conditions which is the relevant case on a manifold with boundary. Starting from a class of symbols that has been investigated before for integer orders in boundary value problems with the transmission property we study operators of arbitrary real orders that play a similar role for operators without the transmission property. Moreover, we show that order reducing symbols have the Volterra property and are parabolic of anisotropy 1; analogous relations are formulated for arbitrary anisotropies. We finally investigate parameter-dependent operators, apply a kernel cut-off construction with respect to the parameter and show that corresponding holomorphic operator-valued Mellin symbols reduce orders in weighted Sobolev spaces on a cone with boundary.
Recht in der Transformation
(2002)
Die jüngsten Veränderungen in den Gesellschaften Mittel- und Osteuropas wurden bisher vor allem unter den Stichworten „Demokratisierung“ und „Marktwirtschaft“ debattiert. Aber wie wurde der Umbruch in Politik und Wirtschaft rechtlich verankert? Welche Probleme entstehen, wenn westliche Normen wie die Vorschriften der EU nach Osteuropa übertragen werden und welche Rolle spielt das Recht beim Aufbau der Wirtschaft? Dieser Band versucht Antworten zu geben, indem er theoretische Fragestellungen mit empirischen Fallstudien aus Ostmittel- und Südosteuropa sowie Zentralasien verbindet.
Contents: Introduction 1 Operators with the transmission property 1.1 Operators on a manifold with boundary 1.2 Conditions with pseudodifferential projections 1.3 Projections and Fredholm families 2 Boundary value problems not requiring the transmission property 2.1 Interior operators 2.2 Edge amplitude functions 2.3 Boundary value problems 3 Operators with global projection conditions 3.1 Construction for boundary symbols 3.2 Ellipticity of boundary value problems with projection data 3.3 Operators of order zero
Prüfungsbereitschaft
(2002)
In the present study, photophysical properties of [N]phenylenes were studied by means of stationary and time-resolved absorption and fluorescence spectroscopy (in THF at room temperature). For biphenylene (1) and linear [3]phenylene (2a), internal conversion (IC) with quantum yields ΦIC > 0.99 is by far the dominant mechanism of S1 state deactivation. Angular [3]phenylene (3a), the zig-zag [4]- and [5]phenylenes (3b), (3c), and the triangular [4]phenylene (4) show fluorescence emission with fluorescence quantum yieds and lifetimes between ΦF = 0.07 for (3a) and 0.21 for (3c) and τF = 20 ns for (3a) and 81 ns for (4). Also, compounds (3) and (4) exhibit triplet formation upon photoexcitation with quantum yields as high as ΦISC = 0.45 for (3c). The strong differences in the fluorescence properties and in the triplet fromation efficiencies between (1) and (2a) on one hand and (3) and (4) on the other are related to the remarkable variation of the internal conversion (IC) rate constants kIC. A tentative classification of (1) and (2a) as “fast IC compounds”, with kIC > 109 s-1, and of (3) and (4) as “slow IC compounds”, with kIC ≈ 107 s-1, is suggested. This classification cannot simply be related to Hückel’s rule-type concepts of aromaticity, because the group of “fast IC compounds” consists of “antiaromatic” (1) and “aromatic” (2a), and the group of “slow IC compounds” consists of “antiaromatic” (3b), (4) and “aromatic” (3a), (3c). The IC in the [N]phenylenes is discussed within the framework of the so-called energy gap law established for non-radiative processes in benzenoid hydrocarbons.
As is known from Kondratyev's work, boundary value problems for elliptic operators on a manifold with conical singularities and boundary are controlled by a principal symbolic hierarchy, where the conormal symbols belong to the typical new components, compared with the smooth case, with interior and boundary symbols. A similar picture may be expected on manifolds with corners when the base of the cone itself is a manifold with conical or edge singularities. This is a natural situation in a number of applications, though with essential new difficulties. We investigate here corresponding conormal symbols in terms of a calculus of holomorphic parameter-dependent edge boundary value problems on the base. We show that a certain kernel cut-off procedure generates all such holomorphic families, modulo smoothing elements, and we establish conormal symbols as an algebra as is necessary for a parametrix constructions in the elliptic case.
We construct algebras of Volterra pseudodifferential operators that contain, in particular, the inverses of the most natural classical systems of parabolic boundary value problems of general form. Parabolicity is determined by the invertibility of the principal symbols, and as a result is equivalent to the invertibility of the operators within the calculus. Existence, uniqueness, regularity, and asymptotics of solutions as t → ∞ are consquences of the mapping properties of the operators in exponentially weighted Sobolev spaces and subspaces with asymptotics. An important aspect of this work is that the microlocal and global kernel structure of the inverse operator (solution operator) of a parabolic boundary value problem for large times is clarified. Moreover, our approach naturally yields qualitative pertubation results for the solvability theory of parabolic boundary value problems. To achieve these results, we assign t = ∞ the meaning of a conical point and treat the operators as totally characteristic pseudodifferential boundary value problems.
On the existence of a non-zero lower bound for the number of Goldbach partitions of an even integer
(2002)
The Goldbach partitions of an even number greater than 2, given by the sums of two prime addends, form the non-empty set for all integers 2n with 2 ≤ n ≤ 2 × 1014. It will be shown how to determine by the method of induction the existence of a non-zero lower bound for the number of Goldbach partitions of all even integers greater than or equal to 4. The proof depends on contour arguments for complex functions in the unit disk.
We introduce the Volterra calculus of pseudodifferential operators with an anisotropic analytic parameter based on "twisted" operator-valued Volterra symbols. We establish the properties of the symbolic and operational calculi, and we give and make use of explicit oscillatory integral formulas on the symbolic side. In particular, we investigate the kernel cut-off operator via direct oscillatory integral techniques purely on symbolic level. We discuss the notion of parabolic for the calculus of Volterra operators, and construct Volterra parametrices for parabolic operators within the calculus.
The genus-dependence of multi-loop superstring ams is estimated at large orders in perturbation theory using the super-Schottky group parameterization of supermoduli space. Restriction of the integration region to a subset of supermoduli space and a single fundamental domain of the super-modular group suggests an exponential dependence on the genus. Upper bounds for these estimates are obtained for arbitrary N-point superstring scattering amplitudes and are shown to be consistent with exact results obtained for special type II string amplitudes for orbifold or Calabi-Yau compactifications. The genus-dependence is then obtained by considering the effect of the remaining contribution to the superstring amplitudes after the coefficients of the formally divergent parts of the integrals vanish as a result of a sum over spin structures. The introduction of supersymmetry therefore leads to the elimination of large-order divergences in string pertubation theory, a result which is based only on the supersymmetric generalization of the polyakov measure and not the gauge group of the string model.
This introduction provides an overview of feminist approaches to International Relations. The authors compare the Anglo-American debate with the Germanspeaking discussion in order to reveal similarities and differences. They identify three particular areas of research that characterize the German-speaking feminist debate in International Relations: (1) works evolving out of peace studies; (2) research on globalization and international economic institutions; (3) studies focusing on women’s movements together with most current works centering around international norms. They argue that feminist approaches to norms constitute a particularly promising research area which provides new "tools" to account for international, regional or domestic policy-change. Gender-sensitive research on norms also allows to address ethical questions that are vital for feminist understandings of science. Moreover, this new focus on norms enables bridge-building between feminism and the mainstream.