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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.
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.
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.
Influence on the admittance of projects in the Context of the FFH-Impact Assessment - Analysis of Procedural Documents. With the impact assessment according to the FFH-Guideline and the regulations based on this guideline very strict standards are applied to the reliability of relevant projects. To provide an overview on the present practice of FFH-impact assessment, procedural documents from the Federal States Bavaria, Brandenburg and Thuringia have been analysed. The survey included the examination of the fields of application of FFH-impact assessments, the evaluation of the relevance of disturbances in the impact regulation and the consideration of the individual examination steps in the following exception procedure for the admittance of projects. The results show that the development of the legal concepts in the reports and the sequence of the separate examination steps display significant insecurity. There are conspicuous tendencies, at least in the examples investigated, towards a practice of the FFH-impact assessment in favour of approval.
Formation of a buried density grating on thermal erasure of azobenzene polymer surface gratings
(2002)
Mit Inkratfttreten des Bundes-Bodenschutzgesetzes (BBodSchG) zum 1. März 1999 sind die wesentlichen Funktionen des Bodens durch ein eigenes Gesetz geschützt. Maßstäbe zur Erfassung von schädigenden Eingriffen in den Boden beschreibt das BBodSchG selbst aber nicht. Deshalb müssen zur Umsetzung der Belange des Bodenschutzes für die Planngspraxis handhabbare Bewertungsmaßstäbe erarbeitet werden, nach denen die entscheidungserheblichen Informationen gezielt herausgearbeitet werden können.Der Beitrag stellt die Entwicklung einer Bewertungsanleitung für das Land Brandenburg vor. Besondere Berücksichtigung finden dabei die Regelungsfunktionen unter Forststandorten, für deren Bewertung die forstlichen Standorterkundungen der 17 Forstamtsbezirke Brandenburgs ausgewertet, hinsichtlich der vorkommenden Leitbodenformen systematisiert sowie den Leitböden aufgrund ihrer Merkmale Wertstufen für einzelne Teilfunktionen zugeordnet worden.Damit ist eine Grundlage geschaffen, um die komplexen Inhalte der Forstlichen Standorterkundung für Planungsaufgaben verfügbar zu machen.
Planetary rings
(2002)
The structure of time series and letter sequences is investigated using the concepts of entropy and complexity. First conditional entropy and transinformation are introduced and several generalizations are discussed. Further several measures of complexity are introduced and discussed. The capability of these concepts to describe the structure of time series and letter sequences generated by nonlinear maps, data series from meteorology, astrophysics, cardiology, cognitive psychology and finance is investigated. The relation between the complexity and the predictability of informational strings is discussed. The relation between local order and the predictability of time series is investigated.
We present a new determination of the time delay of the gravitational lens system HE 1104-1805 (``Double Hamburger'') based on a previously unpublished dataset. We argue that the previously published value of Delta tA-B=0.73 years was affected by a bias of the employed method. We determine a new value of Delta tA-B=0.85+/-0.05 years (2sigma confidence level), using six different techniques based on non interpolation methods in the time domain. The result demonstrates that even in the case of poorly sampled lightcurves, useful information can be obtained with regard to the time delay. The error estimates were calculated through Monte Carlo simulations. With two already existing models for the lens and using its recently determined redshift, we infer a range of values of the Hubble parameter: H0=48+/-4 km s-1 Mpc-1 (2sigma ) for a singular isothermal ellipsoid (SIE) and H0=62+/-4 km s-1 Mpc-1 (2sigma ) for a constant mass-to-light ratio plus shear model (M/L+gamma ). The possibly much larger errors due to systematic uncertainties in modeling the lens potential are not included in this error estimate.
Optimal (und) begründet
(2002)
Thermal properties of block copolymer, poly(N-isopropyl acrylamide)-block-poly(3-[N-(3-methacrylamido-propyl)- N,N-dimethyl]-ammonio propane sulfonate), PNIPA-b-PSPP have been studied in pure and saline (NaCl) aqueous solutions by dynamic laser light scattering (DLS). The copolymer [Mw(PNIPA) 10800 g/mol and Mw(PSPP) 9700 g/mol] exhibits both an upper (UCST 9 oC) and lower (LCST 32 oC) critical solution temperatures in pure water. The addition of NaCl enhances the solubility of the zwitterionic polymer, PSPP, leading to the disappearance of the UCST. On the other hand, the solubility of PNIPA in water decreases as NaCl is added. At 20 oC the copolymer shows a bimodal size distribution through the NaCl concentration range of 0-0.93 M above a certain limiting polymer concentration. The slow and fast components of the diffusion coefficients of the polymer have been calculated. A gradual addition of salt turns the mutual interactions from zwitterionic attractions between PSPP blocks to hydrophobic attractions between PNIPA blocks. The formation of the aggregates and the aggregate sizes at T < UCST and T > LCST are influenced by polymer and salt concentrations. Below UCST the aggregates in saline polymer solutions are larger than those in pure polymer solutions. Above LCST the aggregate size is determined by the salt concentration.
Controlling of Nature Conservation Measures according to the Impact Regulation - Requirements and Methodology Controlling comprises a complex field of (screening, vetting, verification) checking and evaluation measures in terms of process, techniques, implementation, efficiency and of the reaching of goals defined. The significance of controlling will increase with the new $ 18 of the amend nature conservation law, stating that the federal states need to promulgate regulations on the "safeguarding of the implementation" of measures for the avoidance and compensation of interventions. The study explains requirements for the individual controlling steps relevant for the impact regulation and provides examples of practical controls. Starting point for the controls are the planning documents and their determinations. Particular attention should be given to the continuation of the statements of the Landscape conservation support plan (LBP) (in practice not always kept up) and of the Implementation Plan of Landscape measures (LAP). On this basis the implementation controls check if the measures have been carried out properly anf if necessary maintenance measures have been conducted. Functional controls happen on two levels: (a) by checking if avoidance and compensation measures have been selected in coherence with the aims (potential functional fulfilment) and (b) by identifying their efficiency (actual functional fulfilment). Due to the long development period of many measures the functional fulfilment of measures can often only be predicted by estimations. For these prognoses relevant parameters have to be identified and, if necessary, illustrated in scenarios. Additionally, efficiency controls are conducted checking if the measures determined have been selected in coherence with the aims; they belong, however, rather to the preventative-scientific field and not to the controlling of projects. Together the individual steps of controlling can contribute to a quality assurance of the impact regulation.
1. The ability of roach to use cyanobacterial food is generally believed to be one reason for the dominance of roach over perch in eutrophic European lakes. The aim of this study was to test whether cyanobacteria really are a suitable food for juvenile roach. Special attention was paid to differences between the two cyanobacteria species Aphanizomenon and Microcystis which are common in eutrophic lakes and are ingested by roach there. 2. We performed growth and behaviour experiments with juvenile roach fed with zooplankton and the different cyanobacteria. Growth rate with Aphanizomenon was lower than with Daphnia but significantly higher than without food, whereas growth rate with Microcystis was as low as without food. 3. In cultivation experiments of roach faeces, Microcystis was found not to have been digested and grew exponentially after passing through the gut whereas Aphanizomenon stayed at low biomass. Differences in growth were not related to the toxin content of cyanobacteria. Investigations of roach motility showed no differences whether fed Aphanizomenon or Microcystis. 4. In contrast to Microcystis, Aphanizomenon can be regarded as a suitable food source for juvenile roach probably due to its better digestability. We conclude that the ability to feed on cyanobacteria is not a general competitive advantage for roach, but the outcome depends on the species composition of the cyanobacteria.
Juvenile roach (Rutilus rutilus L.) fed on the cyanobacterium Aphanizomenon were able to maintain liver glycogen and muscle protein concentrations. In contrast, internal energy stores of fish fed on the cyanobacterium Microcystis were degraded. However, liver glycogen was higher than in starved fish, suggesting that roach was able to obtain some nutrients (probably carbohydrates) from the mucus cover of Microcystis. Weak assimilation of radiolabeled Microcystis by roach was detectable, and assimilation rates increased with increasing proportion of Aphanizomenon in a mixture of both cyanobacteria. We conclude that the incomplete digestion of Microcystis was the main reason for the negative growth rates of roach when fed on this cyanobacterium species.
Lake ecosystems
(2002)
Interplay between energy limitation and nutritional deficiency: Empirical data and food web models
(2002)
Due to differences in the biochemical composition of autotrophs and their grazers, food quality can strongly influence herbivore population dynamics. Under nutrient depleted conditions the carbon to nutrient ratios of autotrophs can increase to such an extent that consumers become nutrient rather than energy limited. Estimating the importance of this effect in situ in pelagic food webs is complicated by the omnivory of many consumers and rapid nutrient recycling. Isolated predator-prey studies inadequately represent this interaction, instead an ecosystem perspective is required. We used seven years of data from large, deep Lake Constance to develop seasonally resolved flux models of the pelagic food web and analyze the balance between energetic and nutrient constraints. The carbon (C) and phosphorus (P) flows were simultaneously quantified and balanced. C represented food quantity/energy. P was taken as a surrogate of food quality, because algal C:P ratios exceeded the threshold above which P limitation of herbivores is predicted by stoichiometric theory throughout summer and autumn. Primary production exceeded bacterial C production by a factor of 3 but autotrophs and bacteria took up approximately equal amounts of P during summer and autumn. As a consequence the C and P supply of suspension-feeding zooplankton was decoupled: Consumer C demands were largely met by phytoplankton whereas P was mostly obtained from bacteria and their protist predators. The degree of consumer P deficiency varied according to supplementation of their algal diet with P-enriched bacteria or bacterivores. This favored the occurrence of omnivores, i.e. organisms that minimized P deficiencies at the cost of enhanced energy limitation. In contrast with previous perceptions, P remineralization during P depleted summer conditions was dominated by bacterivorous flagellates, carnivorous crustaceans and fish, which fed on prey with an elemental composition similar to their own, whereas herbivores contributed only 30% of P cycling despite their large biomass and C production. Our results suggested a co- limitation of predominantly herbivorous consumers by C and P and a mutual dependence of the two types of deficiency at the individual and system level. This pattern is not specific to pelagic systems but appears to be applicable across ecosystem types.
Die Landschaftsplanung und ihre Integration in die übergeordnete räumliche Planung kann zur konzeptionellen Vorbereitung und Absicherung von Schutzgebietssystemen vor allem die Vorgabe und Verankerung eines breiten, innerfachlich abgeglichenen Zielespektrums leisten. Die moderne wissenschaftliche Erkenntnisse berücksichtigende Herleitung dieser Ziele sowie die Auswahl von geeigneten, möglichst repräsentativen Räumen bedürfen jedoch noch weiterer Fundierung, die nach derzeitigem Stand wohl nicht allein innerhalb der Landschaftsplanung geleistet werden kann. Unter den Planungsebenen ist die Aufgabe der überörtlichen Landschaftsrahmenplanung vorrangig in der Formulierung von Zielgrößen für regionale Umweltqualitätsziele und Mindeststandards (etwa Flächenumfänge, das Spektrum in Schutzgebietssysteme einzubeziehender Lebensräume und Standortausprägungen) zu sehen. Neben einem rein naturschutzfachlichen Konzept ist dabei die gezielte Aufbereitung für die Regionalplanung wichtig. Die Chance der örtlichen Ebene hingegen liegt in einer örtlichen Leitbildentwicklung und Entscheidungsvorbereitung, die unter Integration partizipativer Elemente die Akzeptanz vor Ort erhöhen kann; auch diese kann jedoch nach derzeitigem Stand nicht von der kommunalen Landschaftsplanung allein geleistet werden, sondern bedarf der Ergänzung durch informelle Konzepte und Herangehensweisen. Dabei sind noch nähere Überlegungen notwendig, wie das Zusammenspiel und Ineinandergreifen beider Ebenen der Landschaftsplanung verbessert werden kann: Ein Ansatz, der lediglich seitens der Landschaftsrahmenplanung "top-down" Ziele vorgibt, birgt Gefahr, ins Leere zu laufen, da er an den konkreten Erfordernissen vor Ort vorbeigeht. Vielmehr bedarf es zugleich "bottom-up" einer Hinterfütterung oft abstrakter Zielgrößen mit konkreten, möglichst vor Ort bereits abgestimmten Flächen. Damit alle naturräumlichen Großeinheiten und Großökosysteme in Deutschland über Schutzgebiete repräsentiert sind, wäre des weiteren - wie vom Rat von Sachverständigen für Umweltfragen (SRU 1996, Rn. 262) gefordert - über die Ländergrenzen hinweg die Erarbeitung einer Bundes-Naturschutzkonzeption erforderlich und damit eine Ergänzung der Planungshierarchie. Zwar existieren derartige Vorstellungen bereits als Fachkonzepte (vgl. den Beitrag von FINCK in diesem Band), jedoch bietet das derzeitige rahmenrechtlich organisierte Planungssystem für deren Verankerung noch keinen Ansatz. Vor dem Hintergrund der vielfältigen Anforderungen an Schutzgebietssysteme darf zugleich der breit gefächerte konzeptionelle Auftrag der Landschaftsplanung gerade auch mit Blick auf ihren flächendeckenden Anspruch und die Berücksichtigung der Auswirkungen der verschiedenen Landnutzungen nicht aus den Augen verloren werden. So wurde bereits von anderer Seite (SRU 1996a, Rn. 139) darauf hingewiesen, dass die Entscheidungen der Ministerkonferenz für Raumordnung (MKRO) von 1992 und 1995, 15 % der nicht für Siedlungszwecke genutzten Flächen für den Aufbau eines Biotopverbunds mit Vorrang für Natur und Landschaft zu verwenden, die Gefahr bergen, dass dadurch eine Vorgabe für die Landschaftsrahmenplanung gemacht worden ist, die sie quasi auf die inhaltliche Ausgestaltung von Biotopverbundsystemen reduziert. Es ist wichtig, dass die Landschaftsplanung Schutzgebietssysteme in angemessenem Umfang berücksichtigt und ein breites Spektrum an Schutzzielen verankert, sich dabei aber das Aufgabenfeld ihrerseits zugleich nicht zu sehr auf die zwar originären, aber letztlich doch nur einen Teilbereich des Naturschutzes erfassenden Belange des Flächen- und Gebietsschutzes einengen lässt.
Vortex ripples in sand are studied experimentally in a one-dimensional setup with periodic boundary conditions. The nonlinear evolution, far from the onset of instability, is analyzed in the framework of a simple model developed for homogeneous patterns. The interaction function describing the mass transport between neighboring ripples is extracted from experimental runs using a recently proposed method for data analysis, and the predictions of the model are compared to the experiment. An analytic explanation of the wavelength selection mechanism in the model is provided, and the width of the stable band of ripples is measured.
Amperometric biosensor based on a functionalized gold electrode for the detection of antioxidants
(2002)
Temperature and polymer induced structural changes in SDS/decanol based multilamellar vesicles
(2002)
Many Central Stars of Planetary Nebulae are very similar to massive Wolf-Rayet stars of the carbon sequence with respect to their spectra, chemical composition and wind properties. Therefore their study opens an additional way towards the understanding of the Wolf-Rayet phenomenon. While the study of Line Profile Variation will be difficult, espescially for the very compact early types, the comparision with other hydrogen-deficient Central Stars illuminates the driving mechanism of their winds. We speculate that at least two ingredients are needed. The ionization of their atmpospheres has to be stratified to enable multi-scattering processes and the amount of carbon and oxygen has to be high (more than a few percent by mass).
In order to compress quantum messages without loss of information it is necessary to allow the length of the encoded messages to vary. We develop a general framework for variable-length quantum messages in close analogy to the classecal case and show that lossless compression is only possible if the message to be compressed is known to the sender. The lossless compression of an ensemble of messages is bounded from below by its von-Neumann entropy. We show that it is possible to reduce the number of qbits passing through a quantum channel even below the von-Neumann entropy by adding a classical side-channel. We give an explicit communication protocol that realizes lossless and instantaneous quantum data compression. This protocol can be used for both online quatum communication and storage of quantum data.
We examine the influence of noise on the propagation of harmonic signals with two frequencies through discrete bistable media. We show that random fluctuations enhance propagation of this kind of signals for low coupling strengths, similarly to what happens with purely monochromatic signals. As a more relevant finding, we observe that the frequency being propagated with better efficiency can be selected by tuning the intensity of the noise, in such a way that for large noises the highest frequency is transmitted better than the lower one, whereas for small noises the reverse holds. Such a noise-induced frequency selection can be expected to exist for general multifrequency harmonic signals.
Die Eingriffsregelung im neuen Bundesnaturschutzgesetz : Auwirkungen auf Vollzug und Planungspraxis
(2002)
The definition of "impact" has been widened in the amendment of the Federal Nature Conservation Act. Above all, the decision-making steps and the polluter's obligations have been amended. The issue of "Ersatz" (i.e. compensation measures of the same value) has now to be dealt with before weighting the issues concerning nature conservation. It is foreseeable that the step og weighting will be less important in future and that there will be more flexibility as regards the timing and location of compensation measures. It will be important to formulate requirements for "Ersatzmaßnahmen" (when is a measure of the same value?. Furthermore, landscape planning will gain in importance.
We show that external fluctuations are able to induce propagation of harmonic signals through monostable media. This property is based on the phenomenon of doubly stochastic resonance, where the joint action of multiplicative noise and spatial coupling induces bistability in an otherwise monostable extended medium, and additive noise resonantly enhances the response of the system to a harmonic forcing. Under these conditions, propagation of the harmonic signal through the unforced medium i observed for optimal intensities of the two noises. This noise-induced propagation is studied and quantified in a simple model of coupled nonlinear electronic circuits.
We report on the effect of vibrational resonance in a spatially extended system of coupled noisy oscillators under the action of two periodic forces, a low-frequency one (signal) and a high-frequency one (carrier). Vibrational resonance manifests itself in the fact that for optimally selected values of high-frequency force amplitude, the response of the system to a low-frequency signal is optimal. This phenomenon is a synthesis of two effects, a noise- induced phase transition leading to bistability, and a conventional vibrational resonance, resulting in the optimization of signal processing. Numerical simulations, which demonstrate this effect for an extended system, can be understood by means of a zero-dimensional "effective" model. The behavior of this "effective" model is also confirmed by an experimental realization of an electronic circuit.
Superoxide sensor based on cytochrome c immobilized on mixed-thiol SAM with a new calibration method
(2002)
The analysis of Wolf-Rayet spectra requires adequate model atmospheres which treat the non-LTE radiation transfer in a spherically expanding medium. Present state-of-the-art calculations account for complex model atoms with, typically, a few hundred energy levels and a few thousand spectral lines of He and CNO elements. In the most recent version of our model code, blanketing by millions of lines from iron-group elements is also included. These models have been widely applied for the spectral analysis of WN stars in the Galaxy and LMC. WN spectra can be well reproduced in most cases. WC stars have not yet been analyzed comprehensively, because the agreement with observations becomes satisfactory only when line-blanketed models are applied. The introduction of inhomogeneities (clumping), although treated in a rough approximation, has significantly improved the fit between synthetic and observed spectra with respect to the electron-scattering wings of strong lines. The mass-loss rates obtained from spectral analyses become smaller by a factor 2-3 if clumping is accounted for. A pre-specified velocity law is adopted for our models, but the radiation pressure can be evaluated from our detailed calculation and can be compared a posteriori with the required wind acceleration. Surprisingly we find that the line-blanketed models are not far from being hydrodynamically consistent, thus indicating that radiation pressure is probably the main driving force for the mass-loss from WR stars.
Structural changes induced in bovine serum albumin by covalent attachment of chlorogenic acid
(2002)
Bovine serum albumin (BSA) was modifed by covalent attachment of chlorogenic acid using different concentrations at pH 9. The derivatization was accompanied by a reduction of lysine, cysteine and tryptophan residues. The isoelectric points were shifted to lower pH values and formation of high molecular weight fractions was noted. The structural changes were studied using circular dichroism, differential scanning calorimetry (DSC), intrinsic fluorescence, and binding of anilinonaphthalenesulfonic acid. The results showed that the content of alpha-helix decreased with a parallel increase in unordered structures with higher degrees of derivatization. DSC revealed a decrease in both denaturation temperature and enthalpy. Surface hydrophobicity declined, indicating that hydrophilic regions were exposed on the molecular surface. Proteolytic digestion showed that, at a lower degree of derivatization,the tryptic degradation was most adversely effected, whereas the peptic digestion declined with increasing modification. A trypsin inhibitory effect of the breakdown products released from derivatized BSA was also observed.
The following paper is concerned with the syntax of Slavic clitics, drawing relevant generalizations across the array of West and South Slavic languages. The study concentrates on two currently discussed approaches of generative grammar, the Minimalist Program (MP) and the Optimality Theory (OT). Section 1 provides a short introduction, section 2 gives some basic facts on the phonological and prosodic requirements of the grammar of clitics, section 3 is concerned with the morphosyntax of two types of clitics (simple and special clitics), whereas section 4 summarizes the Slavic data of different clitic classes. In section 5 some derivational approaches of a formal analysis of clitics in generative grammar are demonstrated. Section 6 presents an alternative analysis of clitics based on some recent results of the OT.
Water-soluble block copolymers were prepared from the non-ionic monomer N-isopropylacrylamide (NIPA) and the zwitterionic monomer 3-[N-(3-methacrylamidopropyl)-N,N-dimethyl]-ammonio propane sulfonate (SPP) by sequential free radical polymerization via the RAFT process. Such block copolymers with two hydrophilic blocks exhibit double thermo- responsive behavior in water: the poly-NIPA block shows a lower critical solution temperature, whereas the poly-SPP block exhibits an upper critical solution temperature. Appropriate design of the block lengths leads to block copolymers which stay in solution in the full temperature range between 0°C and 100°C. Both blocks of these polymers dissolve in water at intermediate temperatures, whereas at high temperatures, the poly-NIPA block forms colloidal hydrophobic associates that are kept in solution by the poly-SPP block, and at low temperatures, the poly-SPP block forms colloidal polar aggregates that are kept in solution by the poly-NIPA block. In this way, colloidal aggregates can be prepared in water which switch reversibly, and without any additive, their "inside" to the "outside", and vice versa. The aggregates provide microdomains and surfaces of different character, which can be controlled by a simple thermal stimulus.
A review on the chem. and biochem. of chitin and the chem. and application of chitosan. The following topics were discussed: structure of chitin and chitosan; occurrence and physiol. functions of chitin; detection of chitin in animals and anal. of chitin and chitosan; biosynthesis and biodegrdn. of chitin in animals; prodn. of chitin and chitosan; properties of chitin and chitosan; and applications of chitin and chitosan.