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M-solidity testing systems
(2002)
A polynomial translation of logic programs with nested expressions into disjunctive logic programs
(2002)
SHRIMP U-Pb ages have been obtained for zircon in granitic gneisses from the aureole of the Rogaland anorthosite-norite intrusive complex, both from the ultrahigh temperature (UHT; >900 °C pigeonite-in) zone and from outside the hypersthene-in isograd. Magmatic and metamorphic segments of composite zircon were characterised on the basis of electron backscattered electron and cathodoluminescence images plus trace element analysis. A sample from outside the UHT zone has magmatic cores with an age of 1034 ± 7 Ma (2{sigma}, n = 8) and 1052 ± 5 Ma (1{sigma}, n = 1) overgrown by M1 metamorphic rims giving ages between 1020 ± 7 and 1007 ± 5 Ma.In contrast, samples from the UHT zone exhibit four major age groups:(1) magmatic cores yielding ages over 1500 Ma(2) magmatic cores giving ages of 1034 ± 13 Ma (2{sigma}, n = 4) and 1056 ± 10 Ma (1{sigma}, n = 1)(3) metamorphic overgrowths ranging in age between 1017 ± 6 Ma and 992 ± 7 Ma (1{sigma}) corresponding to the regional M1 Sveconorwegian granulite facies metamorphism, and(4) overgrowths corresponding to M2 UHT contact metamorphism giving values of 922 ± 14 Ma (2{sigma}, n = 6). Recrystallized areas in zircon from both areas define a further age group at 974 ± 13 Ma (2{sigma}, n = 4).This study presents the first evidence from Rogaland for new growth of zircon resulting from UHT contact metamorphism. More importantly, it shows the survival of magmatic and regional metamorphic zircon relics in rocks that experienced a thermal overprint of c. 950 °C for at least 1 Myr. Magmatic and different metamorphic zones in the same zircon are sharply bounded and preserve original crystallization age information, a result inconsistent with some experimental data on Pb diffusion in zircon which predict measurable Pb diffusion under such conditions. The implication is that resetting of zircon ages by diffusion during M2 was negligible in these dry granulite facies rocks. Imaging and Th/U-Y systematics indicate that the main processes affecting zircon were dissolution-reprecipitation in a closed system and solid-state recrystallization during and soon after M1.
Spätabtreibungen
(2002)
Tagungsbericht: Mahler, Claudia: Erfahrungen mit dem neuen deutschen Staatsangehörigkeitsrecht und Rechtsfragen doppelter Staatsangehöriger <2002, Berlin>: Tagungsbericht / 16. Migrationspolitisches Forum veranstaltet vom Forschungszentrum für Internationales und Europäisches Ausländer- und Asylrecht, der German Marshall Fund der USA am 7. Oktober 2002
Länderbericht Pakistan
(2002)
Tagungsbericht: Brinkmeier, Friederike: internationale Tagung, Die Würde des Menschen ist (un)antastbar - Menschenrechtserziehung auf dem Prüfstand <2002, Lutherstadt Wittenberg>: Tagungsbericht / Die Würde des Menschen ist (un)antastbar - Menschenrechtserziehung auf dem Prüfstand, internationale Tagung des UNESCO-Lehrstuhls für Menschenrechtserziehung der Universität Magdeburg, dem Kultusministerium, dem Ministerium für Arbeit, Frauen, Gesundheit und Soziales, der Landeszentrale für politische Bildung des Landes Sachsen-Anhalt am 24. und 25. Januar 2002
Der Aufsatz bestimmt den Begriff der völkerrechtlichen "Diskriminierung" und stellt die allgemeinen völkervertraglichen und völkergewohnheitsrechtlichen Grundlagen zum Schutz vor Rassendiskriminierung vor. Sodann geht die Autorin auf die Regelungen des Internationalen Paktes über bürgerliche und politische Rechte zum Diskriminierungsschutz ein und verdeutlicht den Schutzbereich und die innerstaatliche Bedeutung von Art. 26 an Fallbeispielen.
Das Verbot rassischer Hetze und die Strafbarkeit der sog. Holocaustlüge : Art. 19/20 des IPbpR
(2002)
Eine wertorientierte Rechtsordnung ist vor die Aufgabe gestellt, gegebenenfalls konfligierende Werte untereinander in Ausgleich zu bringen: Freiheit der Meinungsäußerung einerseits, das Verbot bestimmter Inhalte, um Ehre und Leben von Menschen zu schützen, andererseits. Der Aufsatz stellt den Umfang der Meinungsäußerungsfreiheit nach dem Internationalen Pakt über bürgerliche und politische Rechte dar und beschreibt die Möglichkeiten zulässiger Beschränkungen. Er geht weiterhin auf die Strafbarkeit der sogenannten Holocaustlüge in der Bundesrepublik Deutschland ein.
Die frühen Askanier
(2002)
Implizites versus explizites Leistungsstreben : Befunde zur Unabhängigkeit zweier Motivationssysteme
(2002)
Selected enzymes (alpha-amylase, trypsin, and lysozyme) were allowed to react with some simple phenolic and related compounds (caffeic acid, chlorogenic acid, ferulic acid, gallic acid, m-, o-, and p-dihydroxybenzenes, quinic acid, and p-benzoquinone). The derivatized enzymes obtained were characterized in terms of their activity. In vitro experiments showed that the enzymatic activity of the derivatives was adversely affected. This enzyme inhibition depended on the reactivity of the phenolic and related substances tested as well as on the kind of substrate applied. The decrease in the activity was accompanied by a reduction in the amount of free amino and thiol groups, as well as tryptophan residues, which resulted from the covalent attachment of the phenolic and related compounds to these reactive nucleophilic sites in the enzymes. The enzyme inhibition correlates well with the blocking of the mentioned amino acid side chains.
1. Fussmann et al. (2000) presented a simple mechanistic model to explore predator-prey dynamics of a rotifer species feeding on green algae. Predictions were tested against experimental data from a chemostat system housing the planktonic rotifer Brachionus calyciflorus and the green alga Chlorella vulgaris. 2. The model accurately predicted qualitative behaviour of the system (extinction, equilibria and limit cycles), but poorly described features of population cycles such as the period and predator-prey phase relationship. These discrepancies indicate that the model lacked some biological mechanism(s) crucial to population cycles. 3. Here candidate hypotheses for the 'missing biology' are quantified as modifications to the existing model and are evaluated for consistency with the chemostat data. The hypotheses are: (1) viability of eggs produced by rotifers increases with food concentration, (2) nutritional value of algae increases with nitrogen availability, (3) algal physiological state varies with the accumulation of toxins in the chemostat and (4) algae evolve in response to predation. 4. Only Hypothesis 4 is compatible with empirical observations and thus may provide important insight into how prey evolution affects predator- prey dynamics.
Observational data of natural systems, as measured in medical measurements are typically quite different from those obtained in laboratories. Due to the peculiarities of these data, wellknown characteristics, such as power spectra or fractal dimension, often do not provide a suitable description. To study such data, we present here some measures of complexity, which are basing on symbolic dynamics. Firstly, a motivation for using symbolic dynamics and measures of complexity in data analysis based on the logistic map is given and next, two applications to medical data are shown. We demonstrate that symbolic dynamics is a useful tool for the risk assessment of patients after myocardial infarction as well as for the evaluation of th e architecture of human cancellous bone.
Baroreflex sensitivity (BRS) is an important parameter in the classification of patients with reduced left ventricular function. This study aimed at investigating BRS in patients with dilated cardiomyopathy (DCM) and in healthy subjects (controls), as well as comparing the values of BRS parameters with parameters of heart rate variability (HRV) and blood pressure variability (BPV). ECG, continuous blood pressure and respiration curves were recorded for 30 min in 27 DCM patients and 27 control subjects. The Dual Sequence Method (DSM) includes the analysis of spontaneous fluctuations in systolic blood pressure and the corresponding beat-to-beat intervals of heart rate to estimate bradycardic, opposite tachycardic and delayed baroreflex fluctuations. The number of systolic blood pressure/beat-to- beat interval fluctuations in DCM patients was reduced in comparison with controls (DCM patients: male, 154.4+/-93.9 ms/ mmHg; female, 93.7+/-40.5 ms/mmHg; controls: male, 245.5+/-112.9 ms/mmHg; female, 150.6+/-55.8 ms/mmHg, P<0.05). The average slope in DCM patients was lower than in controls (DCM, 5.3+/-1.9 ms/mmHg; controls, 8.0+/-5.4 ms/mmHg; P<0.05). Discriminant function analysis showed that, in the synchronous range of the standard sequence method, the DCM and control groups could be discriminated to only 76% accuracy, whereas the DSM gave an improved accuracy of 84%. The combination of six parameters of HRV, BPV and DSM gives an accuracy of classification of 96%, whereas six parameters of HRV and BPV could separate the two groups to only 88% accuracy. Thus the DSM leads to an improved characterization of autonomous regulation in order to differentiate between DCM patients and healthy subjects. BRS in DCM patients is significantly reduced and apparently less effective.
In mathematical models, very simple communities consisting of three or more species frequently display chaotic dynamics which implies that long-term predictions of the population trajectories in time are impossible. Communities in the wild tend to be more complex, but evidence for chaotic dynamics from such communities is scarce. We used supercomputing power to test the hypothesis that chaotic dynamics become less frequent in model ecosystems when their complexity increases. We determined the dynamical stability of a universe of mathematical, nonlinear food web models with varying degrees of organizational complexity. We found that the frequency of unpredictable, chaotic dynamics increases with the number of trophic levels in a food web but decreases with the degree of complexity. Our results suggest that natural food webs possess architectural properties that may intrinsically lower the likelihood of chaotic community dynamics.
Recurrence-plot-based measures of complexity and its application to heart-rate-variability data
(2002)
The knowledge of transitions between regular, laminar or chaotic behavior is essential to understand the underlying mechanisms behind complex systems. While several linear approaches are often insufficient to describe such processes, there are several nonlinear methods which however require rather long time observations. To overcome these difficulties, we propose measures of complexity based on vertical structures in recurrence plots and apply them to the logistic map as well as to heart rate variability data. For the logistic map these measures enable us not only to detect transitions between chaotic and periodic states, but also to identify laminar states, i.e. chaos-chaos transitions. The traditional recurrence quantification analysis fails to detect the latter transitions. Applying our new measures to the heart rate variability data, we are able to detect and quantify the laminar phases before a life-threatening cardiac arrhythmia occurs thereby facilitating a prediction of such an event. Our findings could be of importance for the therapy of malignant cardiac arrhythmias.
Towards a better understanding of laser beam melt ablation using methods of statistical analysis
(2002)
Laser beam melt ablation, as a contact free machining process, offers several advantages compared to conventional processing mechanisms. Although the idea behind it is rather simple, the process has a major limitation: with increasing ablation rate surface quality of the workpiece processed declines rapidly. The structures observed show a clear dependence of the line energy. In dependence of this parameter several regimes of the process have been separated. These are clearly distinguishable as well in the surfaces obtained as in the signals gained by the measurement of the process emissions which is the observed quantity chosen.
Selected food proteins (myoglobin and soy glycinin) were caused to react with flavonoids (apigenin and quercetin) to estimate the influence of the number and the position of hydroxy substituents. The protein derivatives formed have been charcterized in terms of their properties where they showed changes in the content of free amino groups, tryptophan, and thiol groups. The myoglobin derivatives have also been characterized in terms of their solubility at different pH-values to document the influence on the functional properties. The influence of myoglobin derivatives on the in vitro digestibility with trypsin was also demonstrated, with the digestion of the derivatized myoglobin being favored.
In the CPMAS spectra of soil samples, the paramagnetic soil constituents partially discriminate against the Signal intensity of the 13C atoms.The aim of the study was to check to what extend the signal depression is selective to a certain kind of carbon species. A strong linear correlation between the detectability of carbon and the cube root of wt.% Fe was observed for both, the total signal and the signal of the carbon species as well. For a C:Fe ratio of 1,5 - 20 non selective signal loss caused by the iron particles dominates. Despite the high percentage of non-detectable carbon the 13C CPMAS spectra correctly reflect the relative composition of soil organic matter
Secondary plant metabolites are important native food components, which are becoming more and more interesting due to their physiological effects on humans. Some representatives of these compounds are very reactive and can interact with other main food components like proteins resp. enzymes. This work deals with the reactions of selected enzymes (trypsin, alpha-chymotrypsin and alpha-amylase) with simple phenolic and related substances (caffeic acid, chlorogenic acid, ferulic acid, gallic acid, meta-, ortho- and para-dihydroxybenzene, 1,4-benzoquinone, quinic acid). The derivatives formed were characterized in terms of their activity and selected physicochemical properties. In vitro experiments showed that the proteolytic digestion of food proteins with trypsin and alpha-chymotrypsin derivatives was adversely affected. This decrease depends on the reactivity of the phenolic and related substances tested as well as on the kind of substrate applied. Reactions of phenolic compounds with other enzymes (alpha-amylase and lysozyme) showed similar results with regard to physicochemical properties and their activities.
Der Beitrag zeigt auf, dass sich mit "Wildnis" und Planung Paradoxien in mehrfacher Hinsicht verbinden: So ist in Mitteleuropa die Grenzziehung zwischen anthropogener Nutzung und ungelenkter Entwicklung immer eine bewusst zu treffende Entscheidung - alle unsere Nationalparke und Kernzonen anderer Schutzgebiete beruhen auf diesem Prinzip. Vor dem Hintergrund des umfassenden Gestaltungsanspruchs einer "Landschafts-"Planung gilt es zudem zu beachten, dass umfassende Eingriffe in komplexe Systeme gerade keine Rückkoppelung mehr zulassen, welche Folgen genau auf welche Einzelmaßnahmen zurückzuführen sind und damit in eine "geplante PLanlosigkeit" münden. In Mitteleuropa wird Wildnis großflächig in der Regel nur als Folge einer bewussten Entscheidung möglich sein, jedoch wird daneben immer auch das Prinzip Zufall als wesentlicher Gestalter stehen. Anlass, sich mit dem Thema Wildnis und Planung zu befassen, geben auch Flächenansprüche nach Räumen ungelenkter Entwicklung, die den vorläufigen Stand einer Entwicklung des Naturschutzgedankens markieren, dabei aber in der flächendeckend von menschlicher Einflussnahme geprägten mitteleuropäischen Kulturlandschaft oft im Konflikt zu Nutzungsinteressen stehen. Daneben zeichnet sich unter den Bedingungen des Weltmarktes und der EU-Osterweiterung ein Rückzug der Landwirtschft aus der Fläche ab, der neue Spielräume eröffnet, zugleich aber die Frage nach Lenkungsmöglichkeiten aufwirft. Der bewusste Umgang mit Wildnis im Siedlungsraum beinhaltet dabei mehrere Dimensionen: Eine räumliche (z.B. Zonierungen oder die Lage von Schutzgebieten betreffend), eine zeitliche (z.B. das Zulassen temporären Verwilderns), die Rolle des Menschen (z.B. die Art eines reglementierten/unregelmentierten Zugangs zu den betreffenden Gebieten) und die Art der Vermittlung des Wildnisgedankens (kommen unterstützend pädagogische Hilfsmittel zum Einsatz oder wird ganz bewusst davon abgesehen?). "Planung und Wildnis" bedeutet dabei, sich gerade auch über letzteres, nämlich die Kommunikation und Vermittlung von Naturschutzzielen im klaren zu sein.
We employ classical statistical methods of multivariate classification for the exploitation of the stellar content of the Hamburg/ESO objective prism survey (HES). In a simulation study we investigate the precision of a three- dimensional classification (Teff, log g, [Fe/H]) achievable in the HES for stars in the effective temperature range 5200 K<Teff<6800 K, using Bayes classification. The accuracy in temperature determination is better than 400 K for HES spectra with S/N>10 (typically corresponding to BJ<16.5). The accuracies in log g and [Fe/H] are better than 0.68 dex in the same S/N range. These precisions allow for a very efficient selection of metal-poor stars in the HES. We present a minimum cost rule for compilation of complete samples of objects of a given class, and a rejection rule for identification of corrupted or peculiar spectra. The algorithms we present are being used for the identification of other interesting objects in the HES data base as well, and they are applicable to other existing and future large data sets, such as those to be compiled by the DIVA and GAIA missions.