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The overall program "arborescent numbers" is to similarly perform the constructions from the natural numbers (N) to the positive fractional numbers (Q+) to positive real numbers (R+) beginning with (specific) binary trees instead of natural numbers. N can be regarded as the associative binary trees. The binary trees B and the left-commutative binary trees P allow the hassle-free definition of arbitrary high arithmetic operations (hyper ... hyperpowers). To construct the division trees the algebraic structure "coppice" is introduced which is a group with an addition over which the multiplication is right-distributive. Q+ is the initial associative coppice. The present work accomplishes one step in the program "arborescent numbers". That is the construction of the arborescent equivalent(s) of the positive fractional numbers. These equivalents are the "division binary trees" and the "fractional trees". A representation with decidable word problem for each of them is given. The set of functions f:R1->R1 generated from identity by taking powers is isomorphic to P and can be embedded into a coppice by taking inverses.
In this work the concept of 'context' is considered in five main points. First, context is seen as always necessary for an adequate explication of the concepts of meaning and understanding. Context always plays a role and is not merely brought into consideration when handling a special class of statements or terms, or when there is doubt and clarification is necessary. Second, context cannot be completely reduced to some system of representation. The reason for this is the presence of humans, which is always an important component of a context. Humans experience situations in ways that are not always reducible to symbolic representation. Third, contexts are in principle open. In normal cases they cannot be determined or described in advance. A context is not to be equated with a set of information. Fourth, we understand the parameters of a context pragmatically, which is why we are not led into doubt or even to meaning skepticism by the open nature of a context. This pragmatic knowledge belongs to the category of an ability. Fifth, contexts are, in principle, accessible. This denies the idea that some contexts are incommensurable. There are a number of pragmatic ways of accessing unfamiliar contexts. Some of these are here examined in light of the so-called 'culture wars' in the U.S.A.
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.
Using the gaze-contingent boundary paradigm with the boundary placed after word n, we manipulated preview of word n+2 for fixations on word n. There was no preview benefit for first-pass reading on word n+2, replicating the results of Rayner, Juhasz, and Brown (2007), but there was a preview benefit on the three-letter word n+1, that is, after the boundary, but before word n+2. Additionally, both word n+1 and word n+2 exhibited parafoveal-on-foveal effects on word n. Thus, during a fixation on word n and given a short word n+1, some information is extracted from word n+2, supporting the hypothesis of distributed processing in the perceptual span.
Exploring elections features from a geographical perspective is the focus of this study. Its primary objective is to develop a scientific approach based on geoinformation technology (GIT) that promotes deeper understanding how geographical settings affect the spatial and temporal variations of voting behaviour and election outcomes. For this purpose, the five parliamentary elections (1991-2005) following the political turnaround in 1990 in the South East European reform country Albania have been selected as a case study. Elections, like other social phenomena that do not develop uniformly over a territory, inherit a spatial dimension. Despite of fact that elections have been researched by various scientific disciplines ranging from political science to geography, studies that incorporate their spatial dimension are still limited in number and approaches. Consequently, the methodologies needed to generate an integrated knowledge on many facets that constitute election features are lacking. This study addresses characteristics and interactions of the essential elements involved in an election process. Thus, the baseline of the approach presented here is the exploration of relations between three entities: electorate (political and sociodemographic features), election process (electoral system and code) and place (environment where voters reside). To express this interaction the concept of electoral pattern is introduced. Electoral patterns are defined by the study as the final view of election results, chiefly in tabular and/or map form, generated by the complex interaction of social, economic, juridical, and spatial features of the electorate, which has occurred at a specific time and in a particular geographical location. GIT methods of geoanalysis and geovisualization are used to investigate the characteristics of electoral patterns in their spatial and temporal distribution. Aggregate-level data modelled in map form were used to analyse and visualize the spatial distribution of election patterns components and relations. The spatial dimension of the study is addressed in the following three main relations: One, the relation between place and electorate and its expression through the social, demographic and economic features of the electorate resulting in the profile of the electorate’s context; second, the electorate-election interaction which forms the baseline to explore the perspective of local contextual effects in voting behaviour and election results; third, the relation between geographical location and election outcomes reflecting the implication of determining constituency boundaries on election results. To address the above relations, three types of variables: geo, independent and dependent, have been elaborated and two models have been created. The Data Model, developed in a GIS environment, facilitates structuring of election data in order to perform spatial analysis. The peculiarity of electoral patterns – a multidimensional array that contains information on three variables, stored in data layers of dissimilar spatial units of reference and scales of value measurement – prohibit spatial analysis based on the original source data. To perform a joint spatial analysis it is therefore mandatory to restructure the spatial units of reference while preserving their semantic content. In this operation, all relevant electoral as well as socio-demographic data referenced to different administrative spatial entities are re-referenced to uniform grid cells as virtual spatial units of reference. Depending on the scale of data acquisition and map presentation, a cell width of 0.5 km has been determined. The resulting fine grid forms the basis of subsequent data analyses and correlations. Conversion of the original vector data layers into target raster layers allows for unification of spatial units, at the same time retaining the existing level of detail of the data (variables, uniform distribution over space). This in turn facilitates the integration of the variables studied and the performance of GIS-based spatial analysis. In addition, conversion to raster format makes it possible to assign new values to the original data, which are based on a common scale eliminating existing differences in scale of measurement. Raster format operations of the type described are well-established data analysis techniques in GIT, yet they have rarely been employed to process and analyse electoral data. The Geovisualization Model, developed in a cartographic environment, complements the Data Model. As an analog graphic model it facilitates efficient communication and exploration of geographical information through cartographic visualization. Based on this model, 52 choropleth maps have been generated. They represent the outcome of the GIS-based electoral data analysis. The analog map form allows for in-depth visual analysis and interpretation of the distribution and correlation of the electoral data studied. For researchers, decision makers and a wider public the maps provide easy-to-access information on and promote easy-to-understand insight into the spatial dimension, regional variation and resulting structures of the electoral patterns defined.
This collection contains 13 papers presented in the workshop on the "The Celtic Languages in Contact" organised by Hildegard L. C. Tristram at the XIII International Celtic Congress in Bonn (Germany), July 23rd - 27th, 2007. The authors of two papers from another section also contributed their papers to this volume, as they deal with closely related issues. The time-span covered ranges from potential pre-historic contacts of Celtic with Altaic languages or Nostratic cognates in Celtic, through the hypothesis of Afro-Asiatic as a possible substrate for Celtic, Latin and Gaulish contacts in Gaul, the impact of Vulgar Latin on the formation of the Insular Celtic Languages as a linguistic area (Sprachbund), to various contact scenarios involving the modern Insular Celtic languages as well as English and French. The final paper reflects on the political status of the modern Insular Celtic languages in the Europe of the 27 EU countries.
Phototropic microalgae have a large potential for producing valuable substances for the feed, food, cosmetics, pigment, bioremediation, and pharmacy industries as well as for biotechnological processes. Today it is estimated that the microalgal aquaculture worldwide production is 5000 tons of dry matter per year (not taking into account processed products) making it an approximately $1.25 billion U.S. per year industry. In this work, several spectroscopic techniques were utilized for the investigation of microalgae cells. Specifically, photondensity wave spectroscopy was applied as a technique for the on-line observation of the culture. For effective evaluation of the photosynthetic growth processes, fast and non-invasive sensor systems that analyze the relevant biological and technical process parameters are preferred. Traditionally, the biomass in a photobioreactor is quantified with the help of turbidimetry measurements, which require extensive calibration. Another problem frequently encountered when using spectral analysis for investigating solutions is that samples of interest are often undiluted and highly scattering and do not adhere to Beer-Lambert's law. Due to the fluorescence properties of chlorophyll, fluorescence spectroscopy techniques including fluorescence lifetime imaging and single photon counting could be applied to provide images of the cells as well as determine the effects of excitation intensity on the fluorescence lifetime, which is an indicator of the condition of the cell. A photon density wave is a sinusoidally intensity-modulated optical wave stemming from a point-source of light, which propagates through diffuse medium and exhibits amplitude and phase variations. Light propagation though strongly scattering media can be described by the P1 approximation to the Boltzmann transport equation. Photon density wave spectroscopy enables the ability to differentiate between scattered and absorbed light, which is desired so that an independent determination of the reduced scattering and absorption coefficients can be made. The absorption coefficient is related to the pigment content in the cells, and the reduced scattering coefficient can be used to characterize physical and morphological properties of the medium and was here applied for the determination of the average cell size.
Rezensiertes Werk: Schmidlin, Johann Lorenz: Pictura docens / Johann Lorenz Schmidlin. Hrsg. und übers. von Fritz Felgentreu und Widu-Wolfgang Ehlers. - Stuttgart- Bad Cannstatt : Frommann-Holzboog, 2007. - XCVI, 227 S. : Ill. - (Clavis pansophiae ; 4) ISBN-10 3-7728-2428-5 ISBN-13 978-3-7728-2428-9
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: Geschützt, geduldet, gleichberechtigt ... : die Juden im baden-württembergischen Franken vom 17. Jahrhundert bis zum Ende des Kaiserreichs (1918) / hrsg. von Gerhard Taddey. - Ostfildern : Thorbecke, 2005. - 214 S. : Ill., graph. Darst., Kt. - (Forschungen aus Württembergisch-Franken ; 52) ISBN 3-7995-7653-3
Rezensiertes Werk: Linhardt, Marion: Residenzstadt und Metropole : zu einer kulturellen Topographie des Wiener Unterhaltungstheaters (1858 - 1918) / Marion Linhardt. - Tübingen : Niemeyer, 2006. - VIII, 312 S. : Ill. - (Theatron ; 50) Zugl.: Bayreuth, Univ., Habil.-Schr., 2004 ISBN-10 3-484-66050-3 ISBN-13 978-3-484-66050-2
Mass loss is a very important aspect of the life of massive stars. After briefly reviewing its importance, we discuss the impact of the recently proposed downward revision of mass loss rates due to clumping (difficulty to form Wolf-Rayet stars and production of critically rotating stars). Although a small reduction might be allowed, large reduction factors around ten are disfavoured. We then discuss the possibility of significant mass loss at very low metallicity due to stars reaching break-up velocities and especially due to the metal enrichment of the surface of the star via rotational and convective mixing. This significant mass loss may help the first very massive stars avoid the fate of pair-creation supernova, the chemical signature of which is not observed in extremely metal poor stars. The chemical composition of the very low metallicity winds is very similar to that of the most metal poor star known to date, HE1327-2326 and offer an interesting explanation for the origin of the metals in this star. We also discuss the importance of mass loss in the context of long and soft gamma-ray bursts and pair-creation supernovae. Finally, we would like to stress that mass loss in cooler parts of the HR-diagram (luminous blue variable and yellow and red supergiant stages) are much more uncertain than in the hot part. More work needs to be done in these areas to better constrain the evolution of the most massive stars.
The P v λλ1118, 1128 resonance doublet is an extraordinarily useful diagnostic of O-star winds, because it bypasses the traditional problems associated with determining mass-loss rates from UV resonance lines. We discuss critically the assumptions and uncertainties involved with using P v to diagnose mass-loss rates, and conclude that the large discrepancies between massloss rates determined from P v and the rates determined from “density squared” emission processes pose a significant challenge to the “standard model” of hot-star winds. The disparate measurements can be reconciled if the winds of O-type stars are strongly clumped on small spatial scales, which in turn implies that mass-loss rates based on Hα or radio emission are too large by up to an order of magnitude.
We have analyzed the spectra of seven Galactic O4 supergiants, with the NLTE wind code CMFGEN. For all stars, we have found that clumped wind models match well lines from different species spanning a wavelength range from FUV to optical, and remain consistent with Hα data. We have achieved an excellent match of the P V λλ1118, 1128 resonance doublet and N IV λ1718, as well as He II λ4686 suggesting that our physical description of clumping is adequate. We find very small volume filling factors and that clumping starts deep in the wind, near the sonic point. The most crucial consequence of our analysis is that the mass loss rates of O stars need to be revised downward significantly, by a factor of 3 and more compared to those obtained from smooth-wind models.
The paper describes the exchange program in between the University of Wisconsin/ Milwaukee and the University of Potsdam in the field of economics. It discusses in detail the development of the program, including the problems and challenges. Additionally a brief description of the curriculum is presented. Then the future possibilities of the Transatlantic Degree Program (TDP) are discussed and the influences and problems of the Bologna process analysed.