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The use of unilateral force under George W. Bush is not a new phenomenon in US foreign policy. As the author argues, it is merely a continuation of Bill Clinton’s foreign policy and is deeply rooted in both the foreign policy traditions of Jacksonianism and Wilsonianism. The analysis concludes that Clinton used unilateralist foreign policy with a 'smile' whereas the Bush administration uses it with an attitude.
Contrastive focus
(2007)
The article puts forward a discourse-pragmatic approach to the notoriously evasive phenomena of contrastivity and emphasis. It is argued that occurrences of focus that are treated in terms of ‘contrastive focus’, ‘kontrast’ (Vallduví & Vilkuna 1998) or ‘identificational focus’ (É. Kiss 1998) in the literature should not be analyzed in familiar semantic terms like introduction of alternatives or exhaustivity. Rather, an adequate analysis must take into account discourse-pragmatic notions like hearer expectation or discourse expectability of the focused content in a given discourse situation. The less expected a given content is judged to be for the hearer, relative to the Common Ground, the more likely a speaker is to mark this content by means of special grammatical devices, giving rise to emphasis.
In this paper, we discuss the global existence of solutions for Chemotaxis models with saturation growth. If the coe±cients of the equations are all positive smooth T-periodic functions, then the problem has a positive T-periodic solution, and meanwhile we discuss here the stability problems for the T-periodic solutions.
In this article we construct the fundamental solutions for the wave equation arising in the de Sitter model of the universe. We use the fundamental solutions to represent solutions of the Cauchy problem and to prove the Lp − Lq-decay estimates for the solutions of the equation with and without a source term.
The paper presents a simulation and parameter-estimation approach for evaluating stochastic patterns of population growth and spread of an annual forest herb, Melampyrum pratense (Orobanchaceae). The survival of a species during large-scale changes in land use and climate will depend, to a considerable extent, on its dispersal and colonisation abilities. Predictions on species migration need a combination of field studies and modelling efforts. Our study on the ability of M. pratense to disperse into so far unoccupied areas was based on experiments in secondary woodland in NE Germany. Experiments started in 1997 at three sites where the species was not yet present, with 300 seeds sown within one square meter. Population development was then recorded until 2001 by mapping of individuals with a resolution of 5 cm. Additional observations considered density dependence of seed production. We designed a spatially explicit individual-based computer simulation model to explain the spatial patterns of population development and to predict future population spread. Besides primary drop of seeds (barochory) it assumed secondary seed transport by ants (myrmecochory) with an exponentially decreasing dispersal tail. An important feature of populationpattern explanation was the simultaneous estimation of both population-growth and dispersal parameters from consistent spatio-temporal data sets. As the simulation model produced stochastic time series and random spatially discrete distributions of individuals we estimated parameters by minimising the expectation of weighted sums of squares. These sums-ofsquares criteria considered population sizes, radial population distributions around the area of origin and distributions of individuals within squares of 25*25 cm, the range of density action. Optimal parameter values, together with the precision of the estimates, were obtained from calculating sums of squares in regular grids of parameter values. Our modelling results showed that transport of fractions of seeds by ants over distances of 1…2 m was indispensable for explaining the observed population spread that led to distances of at most 8 m from population origin within 3 years. Projections of population development over 4 additional years gave a diffusion-like increase of population area without any “outposts”. This prediction generated by the simulation model gave a hypothesis which should be revised by additional field observations. Some structural deviations between observations and model output already indicated that for full understanding of population spread the set of dispersal mechanisms assumed in the model may have to be extended by additional features of plant-animal mutualism.
The most massive stars are those with the shortest but most active life. One group of massive stars, the Luminous Blue Variables (LBVs), of which only a few objects are known, are in particular of interest concerning the stability of stars. They have a high mass loss rate and are close to being instable. This is even more likely as rotation becomes an important factor in stellar evolution of these stars. Through massive stellar winds and sometimes giant eruptions, LBV nebulae are formed. Various aspects in the evolution in the LBV phase lead, beside the large scale morphological and kinematical differences, to a diversity of small structures like clumps, rims, and outflows in these nebulae.
In semi-arid savannah ecosystems, the vegetation structure and composition, i.e. the architecture of trees, shrubs, grass tussocks and herbaceous plants, offer a great variety of habitats and niches to sustain animal diversity. In the last decades intensive human land use practises like livestock farming have altered the vegetation in savannah ecosystems worldwide. Extensive grazing leads to a reduction of the perennial and herbaceous vegetation cover, which results in an increased availability of bare soil. Both, the missing competition with perennial grasses and the increase of bare soils favour shrub on open ground and lead to area-wide shrub encroachment. As a consequence of the altered vegetation structure and composition, the structural diversity declines. It has been shown that with decreasing structural diversity animal diversity decline across a variety of taxa. Knowledge on the effects of overgrazing on reptiles, which are an important part of the ecosystem, are missing. Furthermore, the impact of habitat degradation on factors of a species population dynamic and life history, e.g., birth rate, survival rate, predation risk, space requirements or behavioural adaptations are poorly known. Therefore, I investigated the impact of overgrazing on the reptile community in the southern Kalahari. Secondly I analysed population dynamics and the behaviour of the Spotted Sand Lizard, Pedioplanis l. lineoocellata. All four chapters clearly demonstrate that habitat degradation caused by overgrazing had a severe negative impact upon (i) the reptile community as a whole and (ii) on population parameters of Pedioplanis l. lineoocellata. Chapter one showed a significant decline of regional reptile diversity and abundance in degraded habitats. In chapter two I demonstrated that P. lineoocellata moves more frequently, spends more time moving and covers larger distances in degraded than in non-degraded habitats. In addition, home range size of the lizard species increases in degraded habitats as shown by chapter three. Finally, chapter four showed the negative impacts of overgrazing on several population parameters of P. lineoocellata. Absolute population size of adult and juvenile lizards, survival rate and birth rate are significantly lower in degraded habitats. Furthermore, the predation risk was greatly increased in degraded habitats. A combination of a variety of aspects can explain the negative impact of habitat degradation on reptiles. First, reduced prey availability negatively affects survival rate, the birth rate and overall abundance. Second, the loss of perennial plant cover leads to a loss of niches and to a reduction of opportunities to thermoregulate. Furthermore, a loss of cover and is associated with increased predation risk. A major finding of my thesis is that the lizard P. lineoocellata can alter its foraging strategy. Species that are able to adapt and change behaviour, such as P. lineoocellata can effectively buffer against changes in their environment. Furthermore, perennial grass cover can be seen as a crucial ecological component of the vegetation in the semi-arid savannah system of the southern Kalahari. If perennial grass cover is reduced to a certain degree reptile diversity will decline and most other aspects of reptile life history will be negatively influenced. Savannah systems are characterised by a mixture of trees, shrubs and perennial grasses. These three vegetation components determine the composition and structure of the vegetation and accordingly influence the faunal diversity. Trees are viewed as keystone structures and focal points of animal activity for a variety of species. Trees supply animals with shelter, shade and food and act as safe sites, nesting sites, observation posts and foraging sites. Recent research demonstrates a positive influence of shrub patches on animal diversity. Moreover, it would seem that intermediate shrub cover can also sustain viable populations in savannah landscapes as has been demonstrated for small carnivores and rodent species. The influence of perennial grasses on faunal diversity did not receive the same attention as the influence of trees and shrubs. In my thesis I didn’t explicitly measure the direct effects of perennial grasses but my results strongly imply that it has an important role. If the perennial grass cover is significantly depleted my results suggest it will negatively influence reptile diversity and abundance and on several populations parameters of P. lineoocellata. Perennial grass cover is associated with the highest prey abundance, reptile diversity and reptile abundance. It provides reptiles both a refuge from predators and opportunities to optimise thermoregulation. The relevance of each of the three vegetation structural elements is different for each taxa and species. In conclusion, I can all three major vegetation structures in the savannah system are important for faunal diversity.
INTEGRAL tripled the number of super-giant high-mass X-ray binaries (sgHMXB) known in the Galaxy by revealing absorbed and fast transient (SFXT) systems. Quantitative constraints on the wind clumping of massive stars can be obtained from the study of the hard X-ray variability of SFXT. A large fraction of the hard X-ray emission is emitted in the form of flares with a typical duration of 3 ksec, frequency of 7 days and luminosity of $10^{36}$ erg/s. Such flares are most probably emitted by the interaction of a compact object orbiting at $\sim10~R_*$ with wind clumps ($10^{22 ... 23}$ g) representing a large fraction of the stellar mass-loss rate. The density ratio between the clumps and the inter-clump medium is $10^{2 ... 4}$. The parameters of the clumps and of the inter-clump medium, derived from the SFXT flaring behavior, are in good agreement with macro-clumping scenario and line-driven instability simulations. SFXT are likely to have larger orbital radius than classical sgHMXB.
Gewalt und Geschlecht : 12. Fachtagung des Arbeitskreises Geschlechtergeschichte der Frühen Neuzeit
(2007)
Ziel dieser Arbeit war es, die Stickstoff- und Phosphorprozesse im nordostdeutschen Tiefland detailliert zu untersuchen und Handlungsoptionen hinsichtlich der Landnutzung zur nachhaltigen Steuerung der Stickstoff- und Phosphoreinträge in die Fließgewässer aufzuzeigen. Als Grundvoraussetzung für die Modellierung des Nährstoffhaushaltes mussten zunächst die hydrologischen Prozesse und die Abflüsse für die Einzugsgebiete validiert werden. Dafür wurde in dieser Arbeit das ökohydrologische Modell SWIM verwendet. Die Abflussmodellierung umfasste den Zeitraum 1991 - 2000. Die Ergebnisse dazu zeigen, dass SWIM in der Lage war, die hydrologischen Prozesse in den Untersuchungsgebieten adäquat wiederzugeben. Auf der Grundlage der Modellierung des Wasserhaushaltes wurden mit SWIM die Stoffumsatzprozesse für den Zeitraum 1996 - 2000 simuliert. Um dabei besonders das Prozessgeschehen im Tiefland zu berücksichtigen, war die Erweiterung von SWIM um einen Ammonium-Pool mit dessen Umsatzprozessen erforderlich. Außerdem wurde der Prozess der Nährstoffversickerung so ergänzt, dass neben Nitrat auch Ammonium und Phosphat durch das gesamte Bodenprofil verlagert und über die Abflusskomponenten zum Gebietsauslass transportiert werden können. Mit diesen Modellerweiterungen konnten die Stickstoff und Phosphorprozesse in den Untersuchungsgebieten gut abgebildet werden. Mit dem so validierten Modell wurden weitere Anwendungen ermöglicht. Nährstoffsimulationen für den Zeitraum 1981 bis 2000 dienten der Untersuchung des abnehmenden Trends in den Nährstoffkonzentrationen der Nuthe. Die Untersuchungsergebnisse lassen deutlich erkennen, dass sich die Konzentrationen nach 1990 hauptsächlich auf Grund der Reduzierung der Einträge aus punktförmigen Quellen und Rieselfeldern verringert haben. Weitere Modellrechnungen zur Herkunft der Nährstoffe haben ergeben, dass Nitrat überwiegend aus diffusen Quellen, Ammonium und Phosphat dagegen aus punktförmigen Quellen stammen. Als besonders sensitiv auf die Modellergebnisse haben sich die Parameter zu Landnutzung und -management und die Durchwurzelungstiefe der Pflanzen herausgestellt. Abschließend wurden verschiedene Landnutzungsszenarien angewendet. Die Ergebnisse zu den Szenariorechnungen zeigen, dass fast alle vorgegebenen Landnutzungsszenarien zu einer Verringerung der Stickstoff- bzw. Phosphoremissionen führten. Die Anwendung von Szenarien, die alle relevanten Zielvorgaben und Empfehlungen zum Ressourcenschutz berücksichtigen, zeigen die größten Veränderungen.
Nation-Building?
(2007)
Einerseits führt in Entwicklungsländern die Privatisierung von Wasserbetrieben zu Kostensenkungen. Andererseits verändert sie bisherige Möglichkeiten der Teilnahme. Diese wiederspruchsvollen Entwicklungen diskutiert die Autorin an Beispielen aus Südamerika und Südafrika. Künftige Privatisierungen im Bereich Wasser sollten dauerhafte Formen der Mitwirkung ermöglichen.
Rezensiertes Werk: Takebayashi, Tazuko: Zwischen den Kulturen : Deutsches, Tschechisches und Jüdisches in der deutschsprachigen Literatur aus Prag ; ein Beitrag zur xenologischen Literaturforschung interkultureller Germanistik / Tazuko Takebayashi. - Hildesheim [u.a.]: Olms, 2005. - 274 S. : Ill., Kt.- (Echo ; Bd. 8) Zugl.: Bayreuth, Univ., Diss., 2005 ISBN 3-487-12945-0
We present the results of Monte Carlo mass-loss predictions for massive stars covering a wide range of stellar parameters. We critically test our predictions against a range of observed massloss rates – in light of the recent discussions on wind clumping. We also present a model to compute the clumping-induced polarimetric variability of hot stars and we compare this with observations of Luminous Blue Variables, for which polarimetric variability is larger than for O and Wolf-Rayet stars. Luminous Blue Variables comprise an ideal testbed for studies of wind clumping and wind geometry, as well as for wind strength calculations, and we propose they may be direct supernova progenitors.
Recent studies of massive O-type stars present clear evidences of inhomogeneous and clumped winds. O-type (H-rich) central stars of planetary nebulae (CSPNs) are in some ways the low mass–low luminosity analogous of those massive stars. In this contribution, we present preliminary results of our on-going multi-wavelength (FUV, UV and optical) study of the winds of Galactic CSPNs. Particular emphasis will be given to the clumping factors derived by means of optical lines (Hα and Heii 4686) and “classic” FUV (and UV) lines.
Magnetic fields influence the dynamics of hot-star winds and create large scale structure. Based on numerical magnetohydrodynamic (MHD) simulations, we model the wind of θ¹ Ori C, and then use the SEI method to compute synthetic line profiles for a range of viewing angles as function of rotational phase. The resulting dynamic spectrum for a moderately strong line shows a distinct modulation, but with a phase that seems at odds with available observations.
Extract: [...]Of all the print-media newspapers are the most commonly used. They are not literature in the sense of belles letters, but they should not be underestimated in their political, social and personal importance. No other printed product is as closely linked with everyday life as the newspapers. The day begins under their influence, and their contents mirror the events of the day with varying accuracy. Newspapers are strongly reader-oriented. They want to inform, but they also want to instil opinions. Specific choices of information shape the content level. Specific choices of language are resorted to in order to spread opinions and viewpoints. Language creates solidarity between the producers and the consumers of newspapers and thereby supports ideologies by specifically targeted linguistic means. Other strategies are employed for the same purpose, too. Visual aspects are of great importance, such as the typographical layout, the use of pictures, drawings, colours, fonts, etc.[...]
While the Information Structure (IS) is most naturally interpreted as 'structure of information', some may argue that it is structure of something else, and others may object to the use of the word 'structure'. This paper focuses on the question of whether the informational component can have structural properties such that it can be called 'structure'. The preliminary conclusion is that, although there are some vague indications of structurehood in it, it is perhaps better understood to be a representation that encodes a finite set of information-based partitions, rather than structure.
The most recent trend in the studies of LF intervention effects makes crucial reference to focusing effects on the interveners, and this paper critically examines the representative analyses of the focus-based approach. While each analysis has its own merits and shortcomings, I argue that a pragmatic analysis that does not make appeal to syntactic configurations is better equipped to deal with many of the complex and delicate facts surrounding intervention effects.
While there is strong evidence for clumping in the winds of massive hot stars, very little is known about clumping in the winds from Central Stars. We have checked [WC]-type CSPN winds for clumping by inspecting the electron-scattering line wings. At least for three stars we found indications for wind inhomogeneities.
Chapter 1, 2 of the Noctes Atticae reports how the orator and politician Herodes Atticus silences a boastful young Stoic by citing a diatribe of Epictetus. The article shows that Gellius – unlike his own assertion – does not describe a real experience. Instead he dramatizes the text (Epict. diss. 2, 19), which is the origin of the citation. Comparing both texts one finds details of the scenery described, the characterizations of the protagonists as well as the themes discussed quite similar in both the non-cited parts of Epictetus and the text of Gellius. Particularly interesting in that respect is how Gellius takes up citing and its various aspects as it can be found in his model. Epictetus deals with this theme in a critical way, because in his opinion citations of authorities say nothing about the philosophical qualities of the person who uses them. While Gellius’ praxis of citation is formally modelled very closely on Epictetus’ speech, regarding the content he by no means rejects the use of philosophical citations as weapon to beat an opponent in discussion.
Extract: [...]The New English Dictionary, later to become the Oxford English Dictionary, was first published between 1884 and 1928. To add new material, two supplements were issued after this, the first in 1933, and another, more extensive one between 1972 and 1986. In 1989, the Oxford English Dictionary, second edition (OED2) was published, which integrated the material from the original dictionary and the supplements into a single alphabetical sequence. However, virtually all material contained in this edition still remained in the form in which it was originally published. This is the edition most commonly used today, as it forms the basis of the Oxford English Dictionary Online and is also still being sold in print and on CD-ROM. In 1991, a new project started to revise the entire dictionary and bring its entries up to date, both in terms of English usage and in terms of associated scholarship, such as encyclopaedic information and etymologies. The scope was also widened, placing a greater emphasis on English spoken outside Britain. The revision of the dictionary began with the letter M, and the first updated entries were published online in March 2000 (OED3). Quarterly publication of further material has extended the range of revised entries as far as PROTEOSE n. (June 2007). New words from all parts of the alphabet have been published alongside the regular revision.[...]
Following the trails of Alexander von Humboldt in Latin America, by chance you may win, too, some amazing impressions. The view of the German scientist in the actual population is sometimes rather curious, but everytime full of veneration endeavoured towards the conmemoration of his activity.
Alejandro de Humboldt fomentó al joven arquitecto Carlos Nebel como artista en sus palabras “extraordinario” que viajó por México y entre otros dibujó y publicó objetos arqueológicos del tiempo prehispánico, vistas de ciudades mexicanas, de la vestimenta de la gente y de escenas de la vida doméstica.
Luminous Blue Variables show strong changes in their stellar wind on time scales of typically years to decades when they expand and contract radially at approximately constant luminosity. Micro-variability on shorter time scales and amplitudes can be observed superimposed to the larger scale radial changes. I will show long-term time series of high resolution spectra which we have collected in the past 20 years for many of the well known LBVs together with a few time series of weekly sampling (HR Car, R40, R71, R110, R127, S Dor) covering a time windows of up to a few months. Wind variability is seen on short and intermediate time scales with the line profiles changing from P Cygni to inverse P Cygni and double peeked profiles sometimes for the same star and spectral line. On longer time scales the ionisation levels for all chemical elements change drastically due to the strong change of the temperature on the stellar surface. While on the long term the characteristic radial changes may have impact on the over all mass loss rates, the variabilities and asymmetries on short and intermediate time scales may cause false estimates of the mass loss rates when confronting models with the observed line profiles
"Befreiung vom Tabu"
(2007)
Extract: [...]The Roman conquest of what was to become the province of Gallia Narbonensis in the second and then of the whole of Transalpine Gaul in the first century B.C. led to the incorporation into the Roman empire of a large part of the territory in which Gaulish was then spoken.1 In consequence, the vernacular rapidly lost its footing at least in public life and was soon replaced by Latin, the language of the new masters, which enjoyed higher prestige (cf. e.g. Meid 1980: 7-8). On the other hand, Gaulish continued to be written for some three centuries and was probably used in speech even longer, especially in rural areas. We must therefore posit a prolonged period of bilingualism. The effects of this situation on the Latin spoken in the provinces of Gaul seem to have been rather limited. A number of lexical items, mostly from the field of everyday life, and some phonetic characteristics are the sole testimonies of a Gaulish substratum in the variety of Latin that was later to develop into the Romance dialects of France (cf. Meid 1980: 38, fn. 77). [...]
The requirements of modern e-learning techniques change. Aspects such as community interaction, flexibility, pervasive learning and increasing mobility in communication habits become more important. To meet thesechallenges e-learning platforms must provide support on mobile learning. Most approaches try to adopt centralized and static elearning mechanisms to mobile devices. However, often technically it is not possible for all kinds of devices to be connected to a central server. Therefore we introduce an application of a mobile e-learning network which operates totally decentralized with the help of an underlying ad hoc network architecture. Furthermore the concept of ad hoc messaging network (AMNET) is used as basis system architecture for our approach to implement a platform for pervasive mobile elearning.
The requirements of modern e-learning techniques change. Aspects such as community interaction, flexibility, pervasive learning and increasing mobility in communication habits become more important. To meet these challenges e-learning platforms must provide support on mobile learning. Most approaches try to adopt centralised and static e-learning mechanisms to mobile devices. However, often technically it is not possible for all kinds of devices to be connected to a central server. Therefore we introduce an application of a mobile e-learning network which operates totally decentralised with the help of an underlying ad hoc network architecture. Furthermore the concept of ad hoc messaging network (AMNET) is used as basis system architecture for our approach to implement a platform for pervasive mobile e-learning.
Extract: [...] One of the often noted characteristic features of the Celtic languages is the absence of a singular verbal form with the meaning ‘to have’.1 The principal way of expressing possession is through periphrastic constructions with prepositions (such as Irish ag, Scottish Gaelic aig ‘at’; Welsh gan, Breton gant ‘at, with’) and appropriate forms of the substantive verb. Pronominal prepositions, another distinctive feature of the Celtic languages, consist of a preposition and a suffixed pronoun, or rather a pronominal personal ending. This construction may be analyzed as an instance of category fusion. Thus, the Irish and Welsh equivalents of English ‘I have money’ are Tá airgead agam or Mae arian gen i, respectively, both literally meaning ‘is money at-me/with-me’. This note discusses pronominal possessive constructions in Celtic languages (and some comparable examples from Celtic Englishes) and provides some background information on pronominal prepositions and comments on historical developments of these forms. It also discusses some terminological issues involved in labelling the construction in question. [...]
We report on new mass-loss rate estimates for O stars in six massive binaries using the amplitude of orbital-phase dependent, linear-polarimetric variability caused by electron scattering off free electrons in the winds. Our estimated mass-loss rates for luminous O stars are independent of clumping. They suggest similar clumping corrections as for WR stars and do not support the recently proposed reduction in mass-loss rates of O stars by one or two orders of magnitude.
The James Webb Space Telescope (JWST) is a large, infrared-optimized space telescope scheduled for launch in 2013. JWST will find the first stars and galaxies that formed in the early universe, connecting the Big Bang to our own Milky Way galaxy. JWST will peer through dusty clouds to see stars forming planetary systems, connecting the MilkyWay to our own Solar System. JWST’s instruments are designed to work primarily in the infrared range of 1 - 28 μm, with some capability in the visible range. JWST will have a large mirror, 6.5 m in diameter, and will be diffraction-limited at 2 μm (0.1 arcsec resolution). JWST will be placed in an L2 orbit about 1.5 million km from the Earth. The instruments will provide imaging, coronography, and multi-object and integral-field spectroscopy across the 1 - 28 μm wavelength range. The breakthrough capabilities of JWST will enable new studies of massive star winds from the Milky Way to the early universe.
I discuss observational evidence – independent of the direct spectral diagnostics of stellar winds themselves – suggesting that mass-loss rates for O stars need to be revised downward by roughly a factor of three or more, in line with recent observed mass-loss rates for clumped winds. These independent constraints include the large observed mass-loss rates in LBV eruptions, the large masses of evolved massive stars like LBVs and WNH stars, WR stars in lower metallicity environments, observed rotation rates of massive stars at different metallicity, supernovae that seem to defy expectations of high mass-loss rates in stellar evolution, and other clues. I pay particular attention to the role of feedback that would result from higher mass-loss rates, driving the star to the Eddington limit too soon, and therefore making higher rates appear highly implausible. Some of these arguments by themselves may have more than one interpretation, but together they paint a consistent picture that steady line-driven winds of O-type stars have lower mass-loss rates and are significantly clumped.
Formal Poincaré lemma
(2007)
We show how the multiple application of the formal Cauchy-Kovalevskaya theorem leads to the main result of the formal theory of overdetermined systems of partial differential equations. Namely, any sufficiently regular system Au = f with smooth coefficients on an open set U ⊂ Rn admits a solution in smooth sections of a bundle of formal power series, provided that f satisfies a compatibility condition in U.
Indien und die G8
(2007)
Seit 2005 ist Indien als eines der fünf Outreach-Länder in die Diskussionen der G8 eingebunden. Dies geschah wegen seiner Rolle als eine der Kraftquellen der Weltwirtschaft sowie als viertgrößter globaler Markt. Indien betrachtet ein offenes Welthandelregime und einen größeren Kapitalfluss in die Entwicklungsländer als notwendig, um diesen zu helfen, deren Exporte zu steigern, neue Jobs zu schaffen und den Wohlstand ihrer Produzenten zu erhöhen.
New evidence is provided for a grammatical principle that singles out contrastive focus (Rooth 1996; Truckenbrodt 1995) and distinguishes it from discourse-new “informational” focus. Since the prosody of discourse-given constituents may also be distinguished from discourse-new, a three-way distinction in representation is motivated. It is assumed that an F-feature marks just contrastive focus (Jackendoff 1972, Rooth 1992), and that a G-feature marks discoursegiven constituents (Féry and Samek-Lodovici 2006), while discoursenew is unmarked. A crucial argument for G-marking comes from second occurrence focus (SOF) prosody, which arguably derives from a syntactic representation where SOF is both F-marked and G-marked. This analysis relies on a new G-Marking Condition specifying that a contrastive focus may be G-marked only if the focus semantic value of its scope is discourse-given, i.e. only if the contrast itself is given.
Berichtet wird von einer 1858 veröffentlichten Novelle, in der Alexander von Humboldt als Titelheld erschien. Der Verfasser, der preußische Offizier Eugen Hermann von Dedenroth, sandte Humboldt ein Exemplar des Buches in der Hoffnung auf eine lobende Notiz. Stattdessen beklagte sich Humboldt öffentlich „über die Unzartheit deutscher literarischer Gewohnheiten“.
The paper investigates focus marking devices in the scarcely documented North-Ghanaian Gur language Konkomba. The two particles lé and lá occur under specific focus conditions and are therefore regarded as focus markers in the sparse literature. Comparing the distribution and obligatoriness of both alleged focus markers however, I show that one of the particles, lé, is better analyzed as a connective particle, i.e. as a syntactic rather than as a genuine pragmatic marker, and that comparable syntactic focus marking strategies for sentence-initial constituents are also known from related languages.
We present preliminary results of a tailored atmosphere analysis of six Galactic WC stars using UV, optical, and mid-infrared Spitzer IRS data. With these data, we are able to sample regions from 10 to 10³ stellar radii, thus to determine wind clumping in different parts of the wind. Ultimately, derived wind parameters will be used to accuratelymeasure neon abundances, and to so test predicted nuclear-reaction rates.
Behandelte Themen sind: Der Inka-Staat und seine Grundlagen; Schöpfungs- und Zerstörungskraft als Ausdruck von Ordnung im Andenraum; Die praktische Anwendung von Gewalt zur Stabilisierung von Ordnung auf lokaler Ebene; Gewalt und Zerstörung als ordnungsstiftende Elemente in der Kriegsführung der Inka; Die praktische Anwendung von Gewalt und Krieg zur Stabilisierung von Ordnung auf staatlicher Ebene
Ein hoher Verzehr von Obst und Gemüse scheint das Risiko der Inzidenz verschiedener Erkrankungen zu reduzieren. Es wird vermutet, dass eine Gruppe sekundärer Pflanzeninhaltsstoffe, die Flavonoide, hierfür verantwortlich sind. Mögliche Effekte auf die intestinale Barrierefunktion dieser Substanzklasse sind jedoch weitgehend ungeklärt. Parazelluläre Eigenschaften epithelialer Zellen werden hauptsächlich durch die Zell-Zell-Kontakte der Tight Junction (TJ) insbesondere durch die Proteine Occludin und die Claudine definiert. Ziel dieser Arbeit war es, die Effekte des am häufigsten vorkommenden Flavonoids Quercetin auf die Barrierefunktion der Kolonkarzinom-Zelllinie Caco-2 zu untersuchen. Hierbei zeigte sich, dass Quercetin konzentrationsabhängig (50-200 µM) den transepithelialen Widerstand erhöhte. Die Wirkung von 200 µM Quercetin war bereits nach 4 h Inkubation erkennbar und erreichte nach 48 h maximale Werte. Der Wirkverlust, welcher nach 72 h Inkubation eintrat, konnte durch eine tägliche Gabe des Flavonoids verhindert werden. Weiterhin zeigte sich, dass der Quercetin-induzierte Widerstandsanstieg durch mukosale oder serosale Zugabe gleichermaßen auslösbar war. Western Blot-Analysen der TJ-Proteine Occludin, Claudin-1, -3, -4 und -7 ergaben, dass der durch Quercetin-induzierte Widerstandsanstieg insbesondere mit einer Zunahme der Expression des abdichtenden TJ-Proteins Claudin-4 einherging. Quercetin erhöhte ebenfalls die mRNA-Expression von Claudin-4 (quantitative RT-PCR) und bewirkte eine Aktivierung des Claudin-4-Promotors (Luciferase-Reportergen-Analysen). Mittels Immunfluoreszenz-Färbungen und Laserscanning-Mikroskopie konnte ein vermehrter Einbau von Claudin-4 in die TJ nachgewiesen werden. Funktionelle Untersuchungen mittels radioaktiven Fluxmessungen zeigten, dass das Flavonoid die parazelluläre Permeabilität für Natrium und Chlorid reduzierte, aber die Durchlässigkeit von Mannitol als parazellulärer Marker unverändert blieb. Wir konnten hiermit erstmals nachweisen, dass Quercetin die Expression des abdichtenden TJ-Proteins Claudin-4 in den TJ-Komplex verstärkte, wodurch die Ionen-Durchlässigkeit für Natrium und Chlorid vermindert wurde. Das führte zu einer Abdichtung der intestinalen Barriere. Dieser direkte Effekte von Quercetin könnte eine neue Möglichkeit für die Behandlung oder Prävention von Diarrhöe-bedingten intestinalen Barrieredefekten darstellen.
In Gerichtsshows wie „Richter Alexander Hold“, „Richterin Barbara Salesch“ und „Das Strafgericht“ agieren Laiendarsteller semi-spontan als Teilnehmer einer fiktiven Gerichtsverhandlung. Hier wird also eine kommunikative Gattung aus der öffentlichen Kommunikation – die Gerichtsverhandlung – als Folie für eine Unterhaltungssendung genutzt. In dieser Arbeit wird die Gerichtsshow mithilfe des Konzeptes der kommunikativen Gattung beschrieben. Die Darstellung findet auf den verschiedenen Ebenen der kommunikativen Gattung "Binnenebene", "situative Realisierungsebene" und "Außenstruktur" statt. Außerdem wird dem Modell der kommunikativen Gattung als weitere Ebene die "mediale Außenstruktur" hinzugefügt, um die Beschreibbarkeit des Mediengesprächs "Gerichtsshow" zu verbessern. Die Analyse der Gerichtsshow zeigt, dass hier durch die Beteiligten eine Kontextualisierung als Gerichtsverhandlung aufgebaut wird. Die Teilnehmer müssen jedoch zugleich Aufgaben bewältigen, die denen einer Unterhaltungssendung entsprechen. Eine zentrale Aufgabe der Beteiligten ist daher das ständige Aushandeln zwischen der Produktion der Kontextualisierung als Gerichtsverhandlung einerseits und der Erfüllung der Anforderungen einer Unterhaltungssendung andererseits. In diesem Aushandlungsprozess entsteht eine gerichtsshowspezifische Darstellung von Kommunikation vor Gericht, die in dieser Arbeit mithilfe von rechtssoziologischen Konzepten wie dem der "Verfahrensgerechtigkeit" in ihrer Bedeutung im Diskurs um Recht und Gerechtigkeit eingeordnet wird. Die Analyse findet anhand von transkribierten Ausschnitten aus den Sendungen „Richter Alexander Hold“, „Richterin Barbara Salesch“ und „Das Strafgericht“ statt.
How distinct implicit and explicit motive systems differ has long been unclear. Schultheiss' (2001) information processing account of implicit motive arousal hypothesized that implicit motives respond to nonverbal stimuli to influence non-declarative measures of motivation and that explicit motives respond to verbal stimuli to influence declarative measures of motivation. Moreover, in individuals high in referential competence, i.e., with the ability to quickly translate non-verbal stimuli into a verbal representation, implicit motives are thought to respond to verbal stimuli and influence declarative measures of motivation and explicit motives are thought to respond to nonverbal stimuli and to influence non-declarative measures of motivation. The present study tested these hypotheses by assessing liking ratings as a declarative response format and an affective stroop task as a non-declarative response format using emotion words as verbal and emotional facial expressions as non-verbal stimuli. Individual power, affiliation, and achievement motive dispositions were assessed via the Picture Story Excercise for implicit motives and via questionnaires for explicit motives. Referential competence was assessed via a colour-naming/-reading task. I found that as expected explicit and implicit motives overall were not correlated across subjects. Moreover, implicit and explicit motives affected declarative and non-declarative responses for verbal and non-verbal stimuli. As predicted, however, implicit motives responded to verbal stimuli and influenced declarative responses more strongly for individuals high compared to those low in referential competence. Likewise, explicit motive effects were moderated by referential competence in some - but not all - of the predicted conditions. These results show that implicit and explicit motives can influence declarative and non-declarative responses to verbal and non-verbal stimuli. They support the hypothesis that referential processing is needed for implicit motives to respond to verbal stimuli and influence declarative response formats, and they partly support the hypothesis that referential processing plays a role for the influence of explicit motives. Results for explicit motives may suggest that new measures are needed to assess the referential competence to translate verbal stimuli into non-verbal representations. Overall, the findings provide support to the information processing account of implicit motive arousal by Schultheiss' (2001), suggesting that a non-verbal and non-declarative implicit motive system and a distinct verbal and declarative explicit motive system interact via referential processing, i.e., by translating information between representational formats.
Inhalt: - (Nicht-)Belastung deutsch-polnischer Beziehungen - Die Schröder-Erklärung - ...und ihre unterschiedlichen Interpretationen - Eine Frage der Konventionen? - Eine Frage der Gerechtigkeit! - Keine endgültige Antwort - Der polnische Reparationsverzicht von 1953 - Eine rechtsungültige Willenserklärung - ... und ihr protokollarischer Beweis - Ein Posener Vorschlag
Entwicklung, Implementierung und Erprobung eines planetaren Informationssystems auf Basis von ArcGIS
(2007)
Mit der Entwicklung der modernen Raumfahrt Mitte der 60er-Jahre des zwanzigsten Jahrhunderts und der Eroberung des Weltraums brach eine neue Epoche der bis dato auf Beobachtungen mit dem Teleskop gestützten planetaren Forschung an. Während des Wettrennens um die technologische Führerschaft im All zur Zeit des Kalten Krieges war das erste Ziel die Entsendung von Satelliten zur Erdbeobachtung, denen aber schon bald Sonden zum Mond und den benachbarten Planeten folgten. Diese Missionen lieferten eine enorme Fülle von Informationen in Form von Bildern und Messergebnissen in unterschiedlichen Datenformaten. Diese galt und gilt es zu strukturieren, zu verwalten, zu aktualisieren und zu interpretieren. Für die Interpretation terrestrischer Daten werden geographische Informationssysteme (GIS) hinzugezogen, die jedoch für planetare Anwendungen aufgrund unterschiedlicher Voraussetzungen nicht ohne weiteres eingesetzt werden können. Daher wurde im Rahmen dieser Arbeit die für die Verwaltung von geographischen Daten der Erdfernerkundung kommerziell erhältliche Software ArcGIS Desktop 9.0 / 9.1 (ESRI) mit eigenen Programmen und Modulen für die Planetenforschung angepasst. Diese ermöglichen die Aufbereitung und den Import planetarer Bild- und Textinformation in die kommerzielle Software. Zusätzlich wurde eine planetare Datenbank zur Speicherung und zentralen Verwaltung der Informationen aufgebaut. Die im Rahmen dieser Arbeit entwickelten Softwarekomponenten ermöglichen die schnelle und benutzerfreundliche Aufbereitung der in der Datenbank gehaltenen Informationen und das Auslesen in Dateiformate, die für geographische Informationssysteme geeignet sind. Des Weiteren wurde eine „Werkzeugleiste“ für ArcGIS entwickelt, die das Arbeiten mit planetaren Datensätzen beträchtlich beschleunigt und vereinfacht. Sie beinhaltet auch Module zur wissenschaftlichen Interpretation der planetaren Informationen, wie beispielsweise der Berechnung der Oberflächenrauigkeit der Marsoberfläche inklusive der flächendeckenden Kalibrierung der Eingangs-Basisdaten. Exemplarisch konnte gezeigt werden, dass das Verfahren eine verbesserte Berechnung der Oberflächenrauigkeit ermöglicht, als bisher angewandte Ansätze. Zudem wurde eine auf ArcGIS basierende Prozesskette zur Berechnung von hierarchischen Flussnetzen entwickelt und erprobt. Das terrestrische Beispiel, die Analyse eines Abflusssystems auf Island, zeigte eine sehr große Übereinstimmung der errechneten Gewässernetze mit den morphologischen Gegebenheiten vor Ort. Daraus ließ sich eine hohe Genauigkeit der mit demselben Ansatz errechneten Gewässernetze auf dem Mars ableiten. Auf der Grundlage der in dieser Arbeit entwickelten Programme und Module lassen sich auch Daten zukünftiger Missionen aufbereiten und in ein solches System einbinden, um diese mit eigenen Ansätzen zu verwalten, zu aktualisieren und für neue wissenschaftliche Fragestellungen perfekt anzupassen, einzusetzen und zu präsentieren, um so neue wissenschaftliche Erkenntnisse in der Planetenforschung zu gewinnen.
The spatio-temporal evolution of the three recent tsunamogenic earthquakes (TsE) off-coast N-Sumatra (Mw9.3), 28/03/2005 (Mw8.5) off-coast Nias, on 17/07/2006 (Mw7.7) off-coast Java. Start time, duration, and propagation of the rupture are retrieved. All parameters can be obtained rapidly after recording of the first-arrival phases in near-real time processing. We exploit semblance analysis, backpropagation and broad-band seismograms within 30°-95° distance. Image enhancement is reached by stacking the semblance of arrays within different directions. For the three events, the rupture extends over about 1150, 150, and 200km, respectively. The events in 2004, 2005, and 2006 had source durations of at least 480s, 120s, and 180s, respectively. We observe unilateral rupture propagation for all events except for the rupture onset and the Nias event, where there is evidence for a bilateral start of the rupture. Whereas average rupture speed of the events in 2004 and 2005 is in the order of the S-wave speed (≈2.5-3km/s), unusually slow rupturing (≈1.5 km/s) is indicated for the July 2006 event. For the July 2006 event we find rupturing of a 200 x 100 km wide area in at least 2 phases with propagation from NW to SE. The event has some characteristics of a circular rupture followed by unilateral faulting with change in slip rate. Fault area and aftershock distribution coincide. Spatial and temporal resolution are frequency dependent. Studies of a Mw6.0 earthquake on 2006/09/21 and one synthetic source show a ≈1° limit in resolution. Retrieved source area, source duration as well as peak values for semblance and beam power generally increase with the size of the earthquake making possible an automatic detection and classification of large and small earthquakes.
The Mw=7.7 tsunamogenic earthquake (TsE) on 17 July 2006, 08:19:28 shock the Indian Ocean at about 15 km depth off-coast Java, Indonesia. It caused a local tsunami with wave heights exceeding 2 m. The death toll reached several hundred. Thousands of people were displaced. By means of standard array methods, we have investigated the propagation and the extent of the rupture front of the causative earthquake. Waveform similarity is expressed by means of the semblance. We back-propagate the semblance for first-arrival phases recorded at broad-band stations within teleseismic distances (30°-95°). Image enhancement is realised by stacking the semblance of 8 arrays within different epicentral and azimuthal directions. From teleseismic observations we find rupturing of a 200 x 100 km wide area in at least 2 phases with propagation from NW to SE and source duration >125 s. The event has some characteristics of a circular rupture followed by unilateral faulting with change in slip rate. Unusually slow rupturing (≈1.5 km/s) is indicated. Fault area and aftershock distribution coincide. Spatial and temporal resolution are frequency dependent. Studies of a Mw6.0 earthquake on 2006/09/21 and one synthetic source show a ≈1° limit in resolution. Retrieved source area, source duration as well as peak values for semblance and beam power increase with the size of the earthquake making possible an automatic detection and classification of large and small earthquakes.
We present one-dimensional, time-dependent models of the clumps generated by the linedeshadowing instability. In order to follow the clumps out to distances of more than 1000 R∗, we use an efficient moving-box technique. We show that, within the approximations, the wind can remain clumped well into the formation region of the radio continuum.
Gegenstand der Analyse ist die mediale Auseinandersetzung um feministische de/konstruktivistische Theorie und Praxis, die 2006/2007 unter der Überschrift 'Gender Mainstreaming' stattfand. Dominiert wurde die Mediendebatte von einer Reihe antifeministischer Veröffentlichungen in überregionalen (Print- und Online-) Zeitungen und Magazinen; auf ihnen liegt das Hauptaugenmerk meiner Untersuchung. Im Zentrum stehen dabei die Einzelanalysen der Artikel "'Gender Mainstreaming' Politische Geschlechtsumwandlung" (FAZ; Volker Zastrow) und "Der neue Mensch" (Der Spiegel; René Pfister), die unter Hinzuziehung des Debattenkontextes (ca. 50 Artikel) untersucht werden. Die Analyse verfolgt die zentralen diskursiven Strategien, mit denen feministische de/konstruktivistische Theorie und Praxis sowie die Protagonist_innen derselben delegitimiert werden und fragt nach den impliziten wie expliziten Aussagen, den zugrundeliegenden gesellschaftlichen Wissensvorräten, Deutungsrahmen und Ausschlüssen. Theoretisch und methodisch wird eine Perspektive entwickelt, die die Mediendebatte einerseits als Kondensat gesellschaftlicher Wissensvorräte und als Spiegel gesellschaftlicher Machtverhältnisse, andererseits als Produzentin von Wissen und Macht analysierbar macht. Die Forschungsfragen und Analyseergebnisse tangieren entsprechend das gesellschaftlich vorhandene Alltags- und wissenschaftliche Wissen über Geschlecht(erverhältnisse) ebenso wie das ‚neue‘ Wissen, das in der Debatte generiert wird, indem Wissen neu kombiniert, akzentuiert, in neue Kontexte gestellt und den Rezipient_innen zugänglich gemacht wird. Mit welchen Bedeutungen wird der Begriff 'Gender' aufgeladen? Nach welchen Kriterien werden feministische Interventionen beurteilt? Welche Subjekte werden abgewertet oder ausgeschlossen (Homosexuelle, Transgender u.a.)? Welches wissenschaftliche und welches Alltagswissen liegt den (antifeministischen/ transphoben/ homophoben) Aussagen zugrunde? Inwiefern haben de/konstruktivistische Geschlechterkonzepte Eingang gefunden in die öffentliche Geschlechterdebatte? Und schließlich auch: Welche Strategien verfolgten jene medialen Artikulationen, die positiv auf feministische Theorie und Praxis und/oder Gender Mainstreaming Bezug nahmen? 'Gender Mainstreaming' fungierte im untersuchten antifeministischen Strang der Debatte als Aufhänger für einen modernisierten Antifeminismus, der sich gegen sämtliche feministische Politiken und Theorien richtete, die (in der Debatte) mit dem Begriff 'Gender' assoziiert wurden. 'Gender' wurde dabei als politisches Stigmawort mit vagem de/konstruktivistischem Gehalt etabliert. Die untersuchten Delegitimierungsstrategien betreffen den Wahrheitsgehalt feministischer Theorie, die Ziele und die Wirkungen feministischer Politik und die Frage nach den Interessen, die mit feministischen Politiken verfolgt werden. Diesen Strategien liegen (unter anderem) Vorannahmen bezüglich Geschlecht und Geschlechtsidentität, Abwertungen und Ausschlüsse bestimmter geschlechtlich oder sexuell markierter Subjekte, spezifische Deutungen feministischer Politiken und Theorien und die Dethematisierung von Machtverhältnissen zugrunde.
Wider den „euro-atlantischen Internationalismus“ : Berliner Republik und Entgrenzung der Bundeswehr
(2007)
Inhalt: Frieden mit aller Gewalt schaffen? Tatbestand: Staatsterrorismus Das Weißbuch 2006 Bundesverfassungsgericht versus Bundesverwaltungsgericht Weltweites Interventionsrecht Lizenz zum Völkerrechtsbruch „Re-Transformation“ der Bundeswehr Prinzipien für einen sicherheitspolitischen Grundkonsens Breite öffentliche Debatte notwendig
Gamma-rays can be produced by the interaction of a relativistic jet and the matter of the stellar wind in the subclass of massive X-ray binaries known as “microquasars”. The relativistic jet is ejected from the surroundings of the compact object and interacts with cold protons from the stellar wind, producing pions that then quickly decay into gamma-rays. Since the resulting gamma-ray emissivity depends on the target density, the detection of rapid variability in microquasars with GLAST and the new generation of Cherenkov imaging arrays could be used to probe the clumped structure of the stellar wind. In particular, we show here that the relative fluctuation in gamma rays may scale with the square root of the ratio of porosity length to binary separation, $\sqrt{h/a}$, implying for example a ca. 10% variation in gamma ray emission for a quite moderate porosity, h/a ∼ 0.01.
Pensionenunruhen 1513-1516
(2007)
Tras las huellas de Humboldt
(2007)
Esta contribución analiza la estela de influencia dejada por la obra escrita de Alexander von Humboldt en Venezuela. Su recorrido científico expuesto en su obra Viaje a las regiones equinocciales del Nuevo Continente se convirtió en fuente de consulta e inspiración para otros viajeros que, por razones diversas, recorrieron el país a lo largo del siglo XIX. No fueron pocos los visitantes decimonónicos, alemanes y de otras nacionalidades, que tomaron la obra de Humboldt como una referencia para enfrentar los nuevos paisajes que tenían como objetivo visitar. Se destaca especialmente los casos de los alemanes Louis Glöckler, Friedrich Gerstäcker y Carl Geldner, así como del húngaro Pál Rosti. Hubo, en definitiva, viajeros que vinieron a observar lo que ya el sabio alemán había visto con anterioridad, destacando los prodigios de la naturaleza venezolana, tanto por vía de la escritura como de la pintura y la fotografía.
Rezensiertes Werk: Sefer Mišlė šuʿolim (Buch der Fuchsfabeln) / von Jakob Koppelmann. In Originalschrift und Transkription hrsg. und kommentiert von Jutta Schumacher. - Hamburg : Buske, 2006. - XCVII, 359 S. - (Jidische schtudies ; 12) Zugl.: Trier, Univ., Diss. J. Schumacher, 2004/05 u.d.T.: Das jiddische "Buch der Fuchsfabeln" von Jakob Koppelmann in der europäischen Fabeltradition ISBN-10 3-87548-454-1 ISBN-13 978-3-87548-454-0
Rezensiertes Werk: Ibn Verga, Salomo: Schevet Jehuda : ein Buch über das Leiden des jüdischen Volkes im Exil / Salomo Ibn Verga. In der Übers. von Me'ir Wiener. Hrsg., eingeleitet und mit einem Nachw. zur Geschichtsdeutung Salomo Ibn Vergas vers. von Sina Rauschenbach. - 1. Aufl. - Berlin : Parerga, 2006. - 266 S. - (Jüdische Geistesgeschichte ; 6) ISBN 3-937262-34-2
Der Artikel setzt sich mit den Erzählungen des Maassebuches auseinander, welche der Universalgelehrte Johann Christian Schöttgen (1687-1751) in seiner Zeitschrift "Der Rabbiner" publiziert. In seiner Auseinandersetzung mit der jiddischen Literatur befindet sich Schöttgen in einer Reihe mit anderen christlichen Hebraisten, wie zum Beispiel Christoph Helwig (Helvicus, 1581-1617) und Johann Christian Wagenseil (1633-1705).
Massive stars usually form groups such as OB associations. Their fast stellar winds sweep up collectively the surrounding insterstellar medium (ISM) to generate superbubbles. Observations suggest that superbubble evolution on the surrounding ISM can be very irregular. Numerical simulations considering these conditions could help to understand the evolution of these superbubbles and to clarify the dynamics of these objects as well as the difference between observed X-ray luminosities and the predicted ones by the standard model (Weaver et al. 1977).
The H.E.S.S. collaboration recently reported the discovery of VHE γ-ray emission coincident with the young stellar cluster Westerlund 2. This system is known to host a population of hot, massive stars, and, most particularly, the WR binary WR 20a. Particle acceleration to TeV energies in Westerlund 2 can be accomplished in several alternative scenarios, therefore we only discuss energetic constraints based on the total available kinetic energy in the system, the actual mass loss rates of respective cluster members, and implied gamma-ray production from processes such as inverse Compton scattering or neutral pion decay. From the inferred gammaray luminosity of the order of 1035erg/s, implications for the efficiency of converting available kinetic energy into non-thermal radiation associated with stellar winds in the Westerlund 2 cluster are discussed under consideration of either the presence or absence of wind clumping.
Observational evidence exists that winds of massive stars are clumped. Many massive star systems are known as non-thermal particle production sites, as indicated by their synchrotron emission in the radio band. As a consequence they are also considered as candidate sites for non-thermal high-energy photon production up to gamma-ray energies. The present work considers the effects of wind clumpiness expected on the emitting relativistic particle spectrum in colliding wind systems, built up from the pool of thermal wind particles through diffusive particle acceleration, and taking into account inverse Compton and synchrotron losses. In comparison to a homogeneous wind, a clumpy wind causes flux variations of the emitting particle spectrum when the clump enters the wind collision region. It is found that the spectral features associated with this variability moves temporally from low to high energy bands with the time shift between any two spectral bands being dependent on clump size, filling factor, and the energy-dependence of particle energy gains and losses.
Clumping in O-star winds
(2007)
Discussion : X-rays
(2007)
Este estudio ofrece una visión muy general de la estancia de Alexander von Humboldt en España en el primer semestre de 1799 así como de la preparación de su viaje americano durante ese espacio de tiempo. Gracias a diversos documentos que han podido ser localizados en el transcurso de un proyecto de investigación sobre este tema se han podido llenar unos vanos en la investigación humboldtiana. Se presentan los motivos por los que el prusiano, junto a su compañero de viaje francés Aimé Bonpland, emprendió el camino hacía la Península Ibérica, su itinerario y las actividades científicas llevadas a cabo por ellos. Además, se analiza el significado que para él tuvo su estancia en España, interpretado a partir de sus propios escritos, y se describe así mismo su colaboración con la comunidad científica de Madrid. Especial atención se ha puesto en detallar la preparación administrativa en Madrid de su expedición a América, así como los documentos creados y utilizados en este proceso. En el anexo se adjuntan dos documentos poco conocidos: la memoria entregada por Humboldt al rey Carlos IV y un pasaporte firmado por Mariano Luis de Urquijo.
We exploit time-series $FUSE$ spectroscopy to {\it uniquely} probe spatial structure and clumping in the fast wind of the central star of the H-rich planetary nebula NGC~6543 (HD~164963). Episodic and recurrent optical depth enhancements are discovered in the P{\sc v} absorption troughs, with some evidence for a $\sim$ 0.17-day modulation time-scale. The characteristics of these features are essentially identical to the discrete absorption components' (DACs) commonly seen in the UV lines of massive OB stars, suggesting the temporal structures seen in NGC~6543 likely have a physical origin that is similar to that operating in massive, luminous stars. The mechanism for forming coherent perturbations in the outflows is therefore apparently operating equally in the radiation-pressure-driven winds of widely differing momenta ($\mdot$$v_\infty$$R_\star^{0.5}$) and flow times, as represented by OB stars and CSPN.
This contribution presents a quantitative evaluation procedure for Information Retrieval models and the results of this procedure applied on the enhanced Topic-based Vector Space Model (eTVSM). Since the eTVSM is an ontology-based model, its effectiveness heavily depends on the quality of the underlaying ontology. Therefore the model has been tested with different ontologies to evaluate the impact of those ontologies on the effectiveness of the eTVSM. On the highest level of abstraction, the following results have been observed during our evaluation: First, the theoretically deduced statement that the eTVSM has a similar effecitivity like the classic Vector Space Model if a trivial ontology (every term is a concept and it is independet of any other concepts) is used has been approved. Second, we were able to show that the effectiveness of the eTVSM raises if an ontology is used which is only able to resolve synonyms. We were able to derive such kind of ontology automatically from the WordNet ontology. Third, we observed that more powerful ontologies automatically derived from the WordNet, dramatically dropped the effectiveness of the eTVSM model even clearly below the effectiveness level of the Vector Space Model. Fourth, we were able to show that a manually created and optimized ontology is able to raise the effectiveness of the eTVSM to a level which is clearly above the best effectiveness levels we have found in the literature for the Latent Semantic Index model with compareable document sets.
1. Zur Typologisierung dreier Klassen von enschenrechten Menschenrechten 1.1 Rechtssystematisch 1.2 Historisch 1.3 Philosophisch 1.4 Politikwissenschaftlich 2. Die Klasse der WSK-Rechte 2.1. WSK-Rechte insgesamt 2.2 Teilklasse: Wirtschaftliche Rechte 2.3 Teilklasse: Soziale Rechte 2.4 Teilklasse: Kulturelle Rechte 3. Die WSK-Rechte im Einzelnen 3.1 Arbeit 3.2 Gerechte Arbeitsbedingungen 3.3 Gewerkschaftsbildung/Streikrecht 3.4 Soziale Sicherheit 3.5 Schutz der Familie 3.6 Angemessener Lebensstandard 3.7 Ernährung 3.8 Wohnen 3.9 Eigentum 3.10 Gesundheit 3.11 Bildung 3.12 Teilhabe am kulturellen Leben 3.13 Geistiges Eigentum 3.14 Wasser 4. Theorien globaler Gerechtigkeit