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Breton and Irish, two Celtic and strongly endangered European minority languages, enjoy (or suffer) different fates of official recognition. While France does not officially recognise Breton as an independent language and has no even signed the European Charter of Minority Languages as most other EU countries did, Irish is by its constitution the first national language of the Republic of Ireland and therefore enjoys a very high official prestige. It is an obligatory subject in the schools and all EU documents need to be translated both into Irish and English. In spite of this difference of status and prestige, both languages have suffered, during the past 50 years, from a dramatic loss of speakers, as the young generation sees no need to preserve a regionalised minority heritage in a world of globalised communication and exchange. While both inherited languages were, traditionally and sociologically speaking, the medium of communication of the rural population, albeit with a long and venerable written tradition reaching back to the middle ages, the language of the future is that of the urban middle classes learnt as a second language (L2) und for all intents and purposes not used as a community language in the home. Middle class Breton and Irish are token languages, serving its users as identity markers in order to set themselves off from the English and French, most of whom only speak English and French and have no additional regional language. The linguistic gap between the inherited rural and the new urban varieties is great, so that older native rural speakers do not understand school Breton and school Irish. It is predictable that only the urban varieties will survive for still quite a while, whereas the rural varietes are unlikely to escape language death due to the ongoing change of living conditions in the rural areas and the absence of localised language engineering.
Noise-induced dynamics of a prototypical bistable system with delayed feedback is studied theoretically and numerically. For small noise and magnitude of the feedback, the problem is reduced to the analysis of the two-state model with transition rates depending on the earlier state of the system. Analytical solutions for the autocorrelation function and the power spectrum have been found. The power spectrum has a peak at the frequency corresponding to the inverse delay time, whose amplitude has a maximum at a certain noise level, thus demonstrating coherence resonance. The linear response to the external periodic force also has maxima at the frequencies corresponding to the inverse delay time and its harmonics.
In order to broaden our understanding of the eukaryotic CO2- concentrating mechanism the occurrence and localization of a thylakoid-asssocaate carbonic anhydrase (EC 4.2.1.1) were studied in the green algae Tetraedron on minimum and Chlamydomonas noctigama. Both algae induce a CO2-concentrating mechanism when grown under limiting CO2 conditions. Using mass- spectrometric measurements of O-18 exchange from doubly labelled CO2, the presence of a thylakoid-associated carbonic anhydrase was confirmed for both species. From purified thylakoid membranes, photosystem I (PSI), photosystem II (PSII) and the light-harvesting complex of the photosynthetic apparatus were isolated by mild detergent gel. The protein fractions were identified by 77 K fluorescence spectroscopy and immunological studies. A polypeptide was found to immunoreact with an antibody raised against thylakoid carbonic anhydrase (CAH3) from Chlamydomonas reinhardtii. It was found that this polypeptide was mainly associated with PSII, although a certain proportion was also connected to light harvesting complex II. This was confirmed by activity measurements of carbonic anhydrase in isolated bands extracted from the mild detergent gel. The thylakoid carbonic anhydrase isolated from T. minimum had an isoelectric point between 5.4 and 4.8. Together the results are consistent with the hypothesis that thylakoid carbonic anhydrase resides within the lumen where it is associated with the PSII complex.
Determination of phenolic compounds using recombinant tyrosinanse from Streptomyces antibioticus
(2001)
Inhalt: 1 Die öffentliche Diskussion: Blinde Flecken und „offene Selektivität“ 2 Die wissenschaftliche Übersetzung des Konzepts in Politikberatung 3 Nachhaltiger Umgang mit Natur – ein Problem technisch-ökonomischerInstrumente? 3.1 Natur als landschaftsökologisches System 3.2 Systemforschung – der „totale Zugriff“ 3.3 Naturraumpotenziale – unbestimmt bestimmte Bewertung von Natur 3.4 Ökonomische Naturbewertung – die „rohe Sprache des Geldes“ 3.5 Fazit 1: Leitplanken für eine ökologische Modernisierung derkapitalistischen Produktionsweise 4 Nachhaltiger Umgang mit Natur – eine Frage von Sinn und Moral? 4.1 Umweltgerechtes Verhalten – Natur als moralische Instanz 4.2 Wissenschaft – zukunftsfähig durch ein „neues Denken“? 4.3 Fazit 2: Leitbilder für einen ökologisch modernisierten Menschen 5 Abschließendes
The factors that determine the efficiency of energy transfer in aquatic food webs have been investigated for many decades. The plant-animal interface is the most variable and least predictable of all levels in the food web. In order to study determinants of food quality in a large lake and to test the recently proposed central importance of the long-chained eicosapentaenoic acid (EPA) at the pelagic producer-grazer interface, we tested the importance of polyunsaturated fatty acids (PUFAs) at the pelagic producer-consumer interface by correlating sestonic food parameters with somatic growth rates of a clone of Daphnia galeata. Daphnia growth rates were obtained from standardized laboratory experiments spanning one season with Daphnia feeding on natural seston from Lake Constance, a large pre-alpine lake. Somatic growth rates were fitted to sestonic parameters by using a saturation function. A moderate amount of variation was explained when the model included the elemental parameters carbon (r2 = 0.6) and nitrogen (r2 = 0.71). A tighter fit was obtained when sestonic phosphorus was incorporated (r2 = 0.86). The nonlinear regression with EPA was relatively weak (r2 = 0.77), whereas the highest degree of variance was explained by three C18-PUFAs. The best (r2 = 0.95), and only significant, correlation of Daphnia's growth was found with the C18-PUFA a-linolenic acid (a-LA; C18:3n-3). This correlation was weakest in late August when C:P values increased to 300, suggesting that mineral and PUFA- limitation of Daphnia's growth changed seasonally. Sestonic phosphorus and some PUFAs showed not only tight correlations with growth, but also with sestonic alpha-LA content. We computed Monte Carlo simulations to test whether the observed effects of alpha-LA on growth could be accounted for by EPA, phosphorus, or one of the two C18-PUFAs, stearidonic acid (C18:4n-3) and linoleic acid (C18:2n-6). With >99% probability, the correlation of growth with alpha-LA could not be explained by any of these parameters. In order to test for EPA limitation of Daphnia's growth, in parallel with experiments on pure seston, growth was determined on seston supplemented with chemostat-grown, Plimited Stephanodiscus hantzschii, which is rich in EPA. Although supplementation increased the EPA content 80-800x, no significant changes in the nonlinear regression of the growth rates with alpha-LA were found, indicating that growth of Daphnia on pure seston was not EPA limited. This indicates that the two fatty acids, EPA and alpha-LA, were not mutually substitutable biochemical resources and points to different physiological functions of these two PUFAs. These results support the PUFA-limitation hypothesis for sestonic C:P < 300 but are contrary to the hypothesis of a general importance of EPA, since no evidence for EPA limitation was found. It is suggested that the resource ratios of EPA and alpha-LA rather than the absolute concentrations determine which of the two resources is limiting growth.
The filtration rate of Daphnia galeata was determined in in situ experiments in Bautzen Reservoir and in laboratory experiments, where daphnids were exposed to filtrates that previously contained either natural phytoplankton or cultured eukaryotic algae (Scenedesmus obliquus or Asterionella formosa), respectively. Individual filtration rate (FR) was measured using fluorescent beads, taking into account ingested beads in the gut only. Compared to heated control treatments (100°C), dissolved compounds released by the nutritious cultured algae during the preconditioning phase or by the natural phytoplankton assemblages from Bautzen Reservoir strongly reduced the filtration rate of D. galeata (down to 60 %). Heating deactivated these dissolved compounds. A significant correlation was found between primary production measured in situ and the reduction of FR in the filtrate of reservoir water, indicating that extra- cellular products released during photosynthesis triggered the reduction of the filtration rate. The ratio of ingested to collected beads was used to quantify the proportion of food, which was not only collected but passed the mouth of D. galeata. The ratio of ingestion to collection was compared between filtered and unfiltered reservoir water both media identical with respect to the concentration of dissolved compounds, whereas other factors (e. g. food concentration, temperature, filtration rate) were different. The changes in this ratio between filtered and unfiltered reservoir water suggest that D. galeata is capable of a chemosensory control of the ingestion behaviour by detecting external metabolites.
Management-Audit
(2001)
Cafeteria-Systeme
(2001)
In the roughly 20 years of its existence as an observational science, gravitational lensing has established itself as a valuable tool in many astrophysical fields. In the introduction of this review we briefly present the basics of lensing. Then it is shown that the two propagation effects, lensing and scintillation, have a number of properties in common. In the main part various lensing phenomena are discussed with emphasis on recent observations.
Microlensing of Quasars
(2001)
Microlens-induced variability in multiple quasars can be used to study two cosmological issues of great interest, the size and brightness profile of quasars on one hand, and the distribution of compact (dark) matter along the line of sight on the other. Here a summary is given of recent theoretical progress as well as observational evidence for quasar microlensing, plus a discussion of desired observations and required theoretical studies.
Quasar Microlensing
(2001)
Cosmological microlensing
(2001)
Volcano seismology
(2001)
In the middle of the 19th century the question whether expanding civilization and industrialization had an effect on climate was discussed intensely worldwide. It was feared that increasing deforestation would lead to continuous decrease in rainfall. This first scientific discussion about climate change as the result of human intervention was strongly influenced by the research Alexander von Humboldt and Jean-Baptiste Boussingault had undertaken when they investigated the falling water levels of Lake Valencia in Venezuela. This essay aims to clarify the question whether Alexander von Humboldt can be counted among the leading figures of modern environmentalism on account of this research as is being claimed by Richard H. Grove in his influential book Green Imperialism. Colonial Expansion, Tropical Island Edens and Origins of Environmentalism, 1600-1860 (1995).
Phytoplankton dynamics in a shallow eutrophic lake were investigated over a 3-year period with respect to environmental forces which drive species composition and diversity. Diversity was calculated on the basis of species as well as on the basis of their functional properties (the C-R-S-concept). Stratification and water column mixing had a strong impact on phytoplankton composition. Application of a similarity-diversity model revealed that a high diversity was a transient non-stable state, whereas drastic changes or long-lasting stable environmental conditions are characterized by low diversity. This effect was more pronounced when the diversity was calculated on the basis of the phytoplankton species functional properties. Thus, this functional approach supports the intermediate disturbance hypothesis from field data.
Inhaltsübersicht I. Ziele, Maßstäbe und Grundmuster des internationalen Menschenrechtsschutzes II. Strukturen und allgemeine Bedeutung von Individualbeschwerdeverfahren III. Zum Gewinn eines speziellen Individualbeschwerdeverfahrens nach der Kinderrechtskonvention IV.Zur Einklagbarkeit der Konventionsrechte V. Fazit
Ventricular tachycardia or fibrillation (VT) as fatal cardiac arrhythmias are the main factors triggering sudden cardiac death. The objective of this recurrence quantification analysis approach is to find early signs of sustained VT in patients with an implanted cardioverter-defibrillator (ICD). These devices are able to safeguard patients by returning their hearts to a normal rhythm via strong defibrillatory shocks; additionally, they are able to store at least 1000 beat-to-beat intervals immediately before the onset of a life-threatening arrhythmia. We study the
Inhalt: 1 Einleitung 2 Methodologische Überlegungen 3 Das Ende der montanindustriellen Hegemonie 4 Strukturpolitik im post-montanindustriellen Ruhrgebiet 4.1 Akteure und Interessen 4.2 Strukturpolitische Konzepte 4.3 Umsetzungsprobleme und nicht-intendierte Folgen 5 Zusammenfassung und Schlussfolgerungen
We report on deep multi-color imaging (R5sigma = 26) of the Chandra Deep Field South, obtained with the Wide Field Imager (WFI) at the MPG/ESO 2.2 m telescope on La Silla as part of the multi-color survey COMBO-17. As a result we present a catalogue of 63 501 objects in a field measuring 31farcm5 x 30arcmin with astrometry and BVR photometry. A sample of 37 variable objects is selected from two-epoch photometry. We try to give interpretations based on color and variation amplitude.
Cytochrom P450-Elektrochemie
(2001)
We have recently reported the phenomenon of doubly stochastic resonance [Phys. Rev. Lett. 85, 227 (2000)], a synthesis of noise-induced transition and stochastic resonance. The essential feature of this phenomenon is that multiplicative noise induces a bimodality and additive noise causes stochastic resonance behavior in the induced structure. In the present paper we outline possible applications of this effect and design a simple lattice of electronic circuits for the experimental realization of doubly stochastic resonance.
El artículo trata Humboldt como intelectual atlántico, no solo como intelectual europeo. Trata de analizar también el "Ensayo político sobre la Isla de Cuba" como texto clave de la segunda globalización ("revolución industrial"). Bajo el trasfondo de los conocimientos de nosotros sobre la realidad de aquel entonces analiza la presentación humboldtiana de esta realidad durante su estancia en Cuba (1801/1804) y en el "Ensayo" sobre Cuba (1826-1831), así como la posición de Humboldt en el pensamiento histórico. Una tercera parte trata de explicar las relaciones de Humboldt con la red de intelectuales cubanos y con varias personas (Arango, Calvo) en el desarrollo de su obra.
Inhaltsübersicht I. Kurzer Überblick über die Geschichte von Falun Gong 1. Was ist Falun Gong? 2. Die Entwicklung von Falun Gong 3. Der Wendepunkt: Die friedliche Kundgebung der Zehntausend am 25. April 1999 in Peking 4. Verhaftungen und Verbot II. Systematische Verfolgung durch die Staatsgewalt 1. Folter mit Todesfolge 2. Zwangseinweisungen in psychiatrische Anstalten zur "Umerziehung" 3. Brutalitäten gegenüber Inhaftierten 4. Unmenschlichkeit und gesellschaftlicher Terror 5. Duldung kollektiver Vergewaltigung 6. Beförderung statt Bestrafung für die Gewalttäter III. Von Gesetzwidrigkeit bis zum Verfassungsbruch 1. Keine rechtliche Grundlage für das Verbot von Falun Gong 2. Kompetenzüberschreitung des chinesischen Staatspräsidenten Jiang Zemin 3. Fehlende staatliche Legitimation für die Verurteilung von Falun Gong als "böse Religion" 4. Eklatante Verletzungen der Grundrechte Falun Gong-Praktizierender in China IV. Fazit