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Thematic cartography
(2001)
We present an analytical formula for the asymptotic relative entropy of entanglement for Werner states of arbitrary dimensionality. We then demonstrate its validity using methods from convex optimization. This is the first case in which the value of a subadditive entanglement measure has been obtained in the asymptotic limit. This formula also gives the sharpest known upper bound on the distillable entanglement of these states.
Enthalpic barriers to the hydrophobic binding of oligosaccharides to phage P22 tailspike protein
(2001)
Frühe Hochkulturen
(2001)
Frühe Hochkulturen
(2001)
Charisma und Vergemeinschaftung im George- und Horkheimer-Kreis : Gemeinsamkeiten und Gegensätze
(2001)
Andreas von Bülow
(2001)
Hans Leussink
(2001)
Klaus von Dohnanyi
(2001)
Over the last decade the modeling and the storage of biological data has been a topic of wide interest for scientists dealing with biological and biomedical research. Currently most data is still stored in text files which leads to data redundancies and file chaos. In this paper we show how to use relational modeling techniques and relational database technology for modeling and storing biological sequence data, i.e. for data maintained in collections like EMBL or SWISS-PROT to better serve the needs for these application domains. For this reason we propose a two step approach. First, we model the structure (and therefore the meaning of the) data using an Entity-Relationship approach. The ER model leads to a clean design of a relational database schema for storing and retrieving the DNA and protein data extracted from various sources. Our approach provides the clean basis for building complex biological applications that are more amenable to changes and software ports than their file-base counterparts.
Die Vereinten Nationen und die Medien — Vom schwierigen Verhältnis zweier Prügelknaben
I. Einleitung
II. Knackpunkte eines schwierigen Verhältnisses
III. Eine erstaunliche Themenpalette oder: Nicht überall, wo UNO drin ist, steht auch UNO drauf
IV. Zwischen Wunschdenken und Wirklichkeit
V. Therapieansätze
Die Vereinten Nationen und die Medien — Vom schwierigen Verhältnis zweier Prügelknaben — Diskussionszusammenfassung
Energie
(2001)
This article argues that a "Memoir about the Spanish Colonies in South America" allegedly written by Alexander von Humboldt in 1818 for the Holy Alliance’s Conference at Aix-la-Chapelle in reality never existed and therefore could not serve as an impediment to Humboldt’s effort to visit India.
In letters to trusted friends and in conversations Humboldt often showed an inclination to make fun of persons, institutions and situations. In most cases he did this tongue in cheek, rarely hurting people seriously. A special target of Humboldt’s ironical remarks was the Prussian ministry of education and culture because of its animosity to the natural sciences which Humboldt wanted to promote. Often Humboldt expressed his frustration about narrow-mindedness and arrogance which he observed in his hometown of Berlin. Sometimes he had reasons to criticize the Prussian Academies of Sciences and of Arts. Humboldt had a fine sense of humor and many critical remarks can only be understood in the context in which they were made. The reader should therefore be warned, not to take any ironical or sarcastic characterization of a person or an institution literally.
KRB hat an anderer Stelle das Technikverständnis Alexander von Humboldts behandelt und ihn als "geistigen Ahnherrn der Förderung industriellen Fortschritts" gewürdigt. Hier und heute sei Humboldts frühes Interesse an der Anwendung der Botanik belegt, um dem Bevölkerungswachstum, der Preissteigerung bei Lebensmitteln, der Zerrüttung der Staatsfinanzen, dem einreißenden Mangel durch Erschließung neuer Nahrungsquellen, Nutzung ignorierter Naturkräfte und Schaffung neuer Arbeitsplätze zu steuern. Dabei beachtete Humboldt, nahezu noch ein Teenager, bereits ökologische Gesichtspunkte.
Der Aufsatz geht den Vorstellungen Klemperers vom "bedeutenden Indiviuum" nach, die durch Diltheys Vorstellungen beeinflusst sind, wonach das bedeutende Inviduum nicht nur der Grundkörper der Geschichte sei, sondern in "gewissem Verstande die größte Realität derselben". Klemperer versuchte nach seiner Entlassung als Universitätsprofessor dennoch zuerst Literaturhistoriker zu bleiben. Der Entzug der Bücher zwingt ihn zur Autobiografie, er beginnt Curriculum vitae. Aber das "bedeutende Indivuum" geht ihm verloren. Stattdessen wird das Tagebuch zur Chronistenpflicht, der barbarische Alltag und der von Auslöschung bedrohte Mensch soll "festgehalten" werden.
Zur Rolle des Pronomen to/eto in spezifizierenden Kopulaktionstrukturen im polnischen und russischen
(2001)
Preface
(2001)
Vorwort
(2001)
Hydrological modelling of a Pleistocene landslide-dammed lake in the Santa Maria Basin, NW Argentina
(2001)
Bürgerschaftliches Engagement - Konjunktur und Ambivalnez einer gesellschaftspolitischen Debatte
(2001)
Zwischen Arbeitsmarkt und Sozialintegration : zur Bedeutung des Zweiten Arbeitsmarks im Sport
(2001)
"Selbstmanagement" versus "Staatsamateur" : Spitzensportkarrieren in Deutschland und Frankreich
(2001)
Aim and Location In Central European lowland certain plant species grow mainly or exclusively in the corridors of large rivers. In German-speaking plant geography, they are known as "Stromtalpflanzen". The aim of this paper is to review the literature about definitions, explanations and species characteristics and to suggest future directions in research concerning this species group. Results A preliminary list contains 129 ecologically heterogeneous plant species. The mechanisms generating the peculiar distribution pattern may include hydrochory along river corridors, high level of disturbance by water, variable water availability including inundation and summer drought, warm summers, and high nutrient supply on alluvial soils. There is evidence from observational studies for all above mechanisms. However, none of them has been tested experimentally. Demographic data of river corridor plants is limited to very few species, including mainly invasive annuals (Artemisia annua, Bidens frondosa, Cuscuta campestris, Xanthium albinum) and annual (hemi)parasites (Cuscuta campestris, Melampyrum cristatum). Metapopulation studies do not exist to date for European species. part from their habitat requirements, river corridor plants were grouped according to their similarities in overall distribution pattern or in their distribution within particular river corridors. Main conclusions River corridor plants include a high proportion of threatened plant species. In order to preserve them, and in order to understand the mechanisms generating the peculiar distribution pattern, much more has to be known about their population biology and metapopulation dynamics.
Lernprozesse steuern
(2001)
This paper reports on the historical development of the Runge-Kutta methods beginning with the simple Euler method up to an embedded 13-stage method. Moreover, the design and the use of those methods under error order, stability and computation time conditions is edited for students of numerical analysis at undergraduate level. The second part presents applications in natural sciences, compares different methods and illustrates some of the difficulties of numerical solutions.
We describe automatic procedures for the selection of DA white dwarfs in the Hamburg/ESO objective-prism survey (HES). For this purpose, and the selection of other stellar objects (e.g., metal-poor stars and carbon stars), a flexible, robust algorithm for detection of stellar absorption and emission lines in the digital spectra of the HES was developed. Broad band (U-B, B-V) and intermediate band (Strömgren c_1) colours can be derived directly from HES spectra, with precisions of sigma U-B=0.092 mag; sigma B-V=0.095 mag; sigma c_1=0.15 mag. We describe simulation techniques that allow one to convert model or slit spectra to HES spectra. These simulated objective-prism spectra are used to determine quantitative selection criteria, and for the study of selection functions. We present an atlas of simulated HES spectra of DA and DB white dwarfs. Our current selection algorithm is tuned to yield maximum efficiency of the candidate sample (minimum contamination with non-DAs). DA candidates are selected in the B-V versus U-B and c_1 versus W_lambda (Hbeta +Hgamma +Hdelta ) parameter spaces. The contamination of the resulting sample with hot subdwarfs is expected to be as low as ~ 8%, while there is essentially no contamination with main sequence or horizontal branch stars. We estimate that with the present set of criteria, ~ 80% of DAs present in the HES database are recovered. A yet higher degree of internal completeness could be reached at the expense of higher contamination. However, the external completeness is limited by additional losses caused by proper motion effects and the epoch differences between direct and spectral plates used in the HES. Based on observations collected at the European Southern Observatory, La Silla and Paranal, Chile.
If Humboldt had a laptop
(2001)
The difficult publication history and expensive editions of Alexander von Humboldt’s volumes on the expedition to the Americas have resulted in incomplete library holdings which has limited scholarly access and sometimes caused unbalanced scholarship. A plan for a Humboldt Digital Library examines the structures and features of this representational system in print and proposes models for converting these materials to electronic form. Several issues posed by Humboldt’s works include: establishing authoritative standard editions in several languages, creating high-resolution access to the many visual innovations in the works, and using software to restore the grand concept that all of the separate disciplines of study can be seen as interrelated parts of the whole. Using techniques of geographic visualization, a prototype is planned which will connect this historical body of knowledge with modern scientific databases.
Laser beam melt ablation - a contact-free machining process - offers several advantages compared to conventional processing mechanisms: there exists no tool wear and even extremely hard or brittle materials can be processed. During ablation the workpiece is molten by a CO2-laser beam, this melt is then driven out by the impulse of a process gas. The idea behind laser ablation is rather simple, but it has a major limitation in practical applications: with increasing ablation rates surface quality of the workpiece processed declines rapidly. At high ablation rates, depending on the process parameters different periodic-like structures can be observed on the ablated surface. These structures show a dependence on the line energy, which has been identified as a fundamental control parameter. In dependence on this parameter several regimes with different behaviours of the process have been separated. These regimes are distinguishable as well in the surfaces obtained as in the signals gained by the measurement of the process emissions. Further aim is to identify the different modes of the system and reach a deeper understanding of the dynamics of the molten material in order to understand the formation of these surface structures. With this it should be possible to influence the system in the direction of avoiding structure formation even at high ablation rates. Relying on the results on-line monitoring and control of the process should be studied.
We study the dynamo properties of asymmetric square patterns in Boussinesq Rayleigh-B'enard convection in a plane horizontal layer. Cases without rotation and with weak rotation about a vertical axis are considered. There exist different types of solutions distinguished by their symmetry, among them such with flows possessing a net helicity and being capable of kinematic dynamo action in the presence as well as in the absence of rotation. In the nonrotating case these flows are, however, always only kinematic, not nonlinear dynamos. Nonlinearly the back-reaction of the magnetic field then forces the solution into the basin of attraction of a roll pattern incapable of dynamo action. But with rotation added parameter regions are found where the Coriolis force counteracts the Lorentz force in such a way that the asymmetric squares are also nonlinear dynamos.
We numerically investigate nonlinear asymmetric square patterns in a horizontal convection layer with up-down reflection symmetry. As a novel feature we find the patterns to appear via the skewed varicose instability of rolls. The time-independent nonlinear state is generated by two unstable checkerboard (symmetric square) patterns and their nonlinear interaction. As the bouyancy forces increase the interacting modes give rise to bifurcations leading to a periodic alternation between a nonequilateral hexagonal pattern and the square pattern or to different kinds of standing oscillations.