114 search hits
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Bayreuther Hausnummern-, Adreß- und Einwohnerbücher 1808
(2007)
- Hausnummern-, Adreß- und Einwohnerbücher – die Titelformulierungen wechseln – sind kurzlebige Gebrauchsschriften. Durch Zuzug und Abwanderung, durch Neubau, Verkauf oder Abriß von Häusern, durch Änderungen in der Nummernfolge und durch Um- oder Neubenennung von Straßen verlieren sie schnell an Aktualität. Sie dokumentieren gleichsam in einer Momentaufnahme Anlage und Ausdehnung einer Stadt sowie Zahl, Sozialstruktur, Haus- und Grundbesitz ihrer Bewohner. Darüber hinaus gestatten sie nicht selten durch beigefügte Firmenverzeichnisse und Anzeigenteile und durch Auflistung von Behörden, Institutionen und Vereinen einen Blick auf das wirtschaftliche, das öffentliche und das gesellige Leben. In ihrer zeitlichen Abfolge erhellen sie längsschnittähnlich den Wandel und die Entwicklung eines städtischen Gemeinwesens. Unter beiden Gesichtspunkten – Längsschnitt und Momentaufnahme – sind sie für den Historiker von erheblichem Quellenwert. Die vorliegende Edition umfaßt sämtliche gedruckten Bayreuther Hausnummern-, Adreß- und Einwohnerbücher der Vorkriegszeit (1807 - 1937).
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Bayreuther Hausnummern-, Adreß- und Einwohnerbücher 1807
(2007)
- Hausnummern-, Adreß- und Einwohnerbücher – die Titelformulierungen wechseln – sind kurzlebige Gebrauchsschriften. Durch Zuzug und Abwanderung, durch Neubau, Verkauf oder Abriß von Häusern, durch Änderungen in der Nummernfolge und durch Um- oder Neubenennung von Straßen verlieren sie schnell an Aktualität. Sie dokumentieren gleichsam in einer Momentaufnahme Anlage und Ausdehnung einer Stadt sowie Zahl, Sozialstruktur, Haus- und Grundbesitz ihrer Bewohner. Darüber hinaus gestatten sie nicht selten durch beigefügte Firmenverzeichnisse und Anzeigenteile und durch Auflistung von Behörden, Institutionen und Vereinen einen Blick auf das wirtschaftliche, das öffentliche und das gesellige Leben. In ihrer zeitlichen Abfolge erhellen sie längsschnittähnlich den Wandel und die Entwicklung eines städtischen Gemeinwesens. Unter beiden Gesichtspunkten – Längsschnitt und Momentaufnahme – sind sie für den Historiker von erheblichem Quellenwert. Die vorliegende Edition umfaßt sämtliche gedruckten Bayreuther Hausnummern-, Adreß- und Einwohnerbücher der Vorkriegszeit (1807 - 1937).
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Bayreuther Hausnummern-, Adreß- und Einwohnerbücher - Einführung
(2007)
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Rainer-Maria Kiel
- Hausnummern-, Adreß- und Einwohnerbücher – die Titelformulierungen wechseln – sind kurzlebige Gebrauchsschriften. Durch Zuzug und Abwanderung, durch Neubau, Verkauf oder Abriß von Häusern, durch Änderungen in der Nummernfolge und durch Um- oder Neubenennung von Straßen verlieren sie schnell an Aktualität. Sie dokumentieren gleichsam in einer Momentaufnahme Anlage und Ausdehnung einer Stadt sowie Zahl, Sozialstruktur, Haus- und Grundbesitz ihrer Bewohner. Darüber hinaus gestatten sie nicht selten durch beigefügte Firmenverzeichnisse und Anzeigenteile und durch Auflistung von Behörden, Institutionen und Vereinen einen Blick auf das wirtschaftliche, das öffentliche und das gesellige Leben. In ihrer zeitlichen Abfolge erhellen sie längsschnittähnlich den Wandel und die Entwicklung eines städtischen Gemeinwesens. Unter beiden Gesichtspunkten – Längsschnitt und Momentaufnahme – sind sie für den Historiker von erheblichem Quellenwert. Die vorliegende Edition umfaßt sämtliche gedruckten Bayreuther Hausnummern-, Adreß- und Einwohnerbücher der Vorkriegszeit (1807 - 1937).
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Evolutionary and proximate constraints on egg size in butterflies
(2007)
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Stephanie Sandra Bauerfeind
- Arthropod egg and thus progeny size is an evolutionary and ecologically significant trait, showing tremendous variation within and across species. The high variation found is caused by a complex set of interacting proximate and evolutionary factors, but despite increasing effort this network is still only partially resolved. Using butterflies as model organisms, this study focuses on two main factors that are assumed to strongly shape variation in offspring size and number: maternal size and maternal nutrition. Both are assumed to affect reproductive traits and thereby maternal and offspring fitness. Phenotypic correlations between maternal size and egg size within various butterfly species as well as a two-trait selection experiment on simultaneous changes in both traits in the butterfly Bicyclus anynana clearly demonstrated that the importance of maternal size in shaping variation in egg size is limited, both in sense of a morphological as well as an evolutionary constraint. These results strongly contrast to the general assumption of a positive scaling relationship between both traits. This is one of the few studies addressing the issue of evolutionary constraints directly, employing artificial two-trait selection which has been proven to be a powerful tool to unravel genetic variances and covariances that underlie the evolution of traits. While the importance of maternal size in shaping variation in egg size is limited, proximate factors including larval and adult crowding as well as the quantity and quality of available food during the larval and adult stage affect variation in reproductive traits to a high degree. In the butterfly B. anynana, larval and adult densities had surprisingly little effects on female reproduction, whereas dietary limitations yielded strong responses in female reproductive output. Larval food stress reduced fecundity and reproductive investment (mediated through a reduction in body size), but effects on egg size were overall marginal. Additional negative effects of adult food stress on fecundity were largely confined to females being fed as larvae ad libitum, while those being previously starved showed reduced performance regardless of adult income. When abundantly fed during the larval stage, a limitation of adult resources reduced reproductive output, proving the need for adult feeding in B. anynana for egg production. Thus, restricted food access in different developmental stages of B. anynana sets different limits to reproduction, either posed by shortage of larval-derived storage reserves (i.e. nitrogenous compounds) or adult income (i.e. carbohydrates). Consequently, restrictions in both, larval- and adult-derived resources, limit reproduction in B. anynana. Further, this study deals with questions regarding effects of different adult dietary compounds for a fruit-feeding butterfly being novel in its reductionist approach and in the breadth of different nutrient classes considered. This study demonstrates that B. anynana relies to a large extent on adult feeding in order to realise full reproductive output. Female B. anynana require adult-derived carbohydrates for egg production and exhibit a tremendous gain in reproductive output when fed on fruit as compared to sucrose solutions. Contrary to initial expectations, I could not pinpoint a single pivotal substance (in addition to sucrose) that was able to elicit a comparably high reproductive performance as banana, although I tested the micronutrients being most abundantly available in banana (minerals: potassium and magnesium chloride; a mixture of vitamins and a combination of both) and all major substances known to be involved in insect egg production (amino acids, cholesterol, polyunsaturated fatty acids). Further, it is also excluded that the growth of microorganisms and fungi (associated with the production of fermentative products like organic acids and alcohols, thereby providing access to additional resources) explains the found results. In conclusion, reproduction does not only depend on a small number of adult-derived nutrients, but on a larger number having relatively small effects each. Thus, resource congruence (the use of nutrient types in a specified ratio) rather than any specific component may be the key to answer the question.
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Single Molecule Study of Polymer-Surfactant Interactions
(2007)
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John Bosco Stanislaus
- The interactions between the anionic surfactant sodium dodecyl sulfate (SDS) and a hydrophobically modified non ionic polymer, methylcellulose (MC), have been investigated in aqueous solution by fluorescence correlation spectroscopy (FCS), cryo-TEM, turbidity and rheology. The micelle formation of SDS is followed with cationic Cresyl Violet perchlorate dye via diffusion time. The opposite polarity of dye is suitable to aggregate with micelles and act as a labeled dye. Two major studies focused in the research work are concentration dependent and temperature measurements to understand the interactions of MC/SDS aggregates. The concentration of SDS is varied to a wide range in the mixture by fixing the concentration of MC. By this approach, the changes in the aggregation and the conformations of MC chains are being studied. Similar studies have been repeated at various temperatures in the range of 25-60 °C to understand the changes in gelation properties of MC. To understand the results of the above mentioned studies of MC/SDS, the behavior of MC and SDS is analyzed individually. In this line, the critical micelle concentration (CMC) of SDS has found with FCS measurements is in good agreement with literature value obtained from ‘classical methods’. The hydrodynamic radius of SDS micelle around CMC is found to be ~ 2.0 nm. The shape of the autocorrelation curves and number of dye particles in the focal volume also supports to follow the SDS micelle. When varying the concentration of MC, slight changes in the diffusion time of dye are observed. The MC/SDS mixtures show huge increase in the diffusion time compared to the individual components MC and SDS. At constant MC concentration the diffusion time of single aggregates increases gradually up to a certain SDS concentration and decreases to a minimum when the SDS concentration is further increased. This behavior coincides with the behavior of the zero shear viscosity. Two different fractions viz fast diffusing fraction of dye molecule along with the larger aggregates are observed in between the critical aggregation concentration (CAC) and end of aggregation (EOA). FCS is used to follow the dynamics of single aggregates of the different populations. At very high concentration of SDS, MC/SDS mixtures show the worm like structure in cryoTEM measurements. A model is proposed based on FCS, cryoTEM and rheology measurements to explain the effect of surfactant concentration on polymer conformation and aggregation size. While varying the temperature, MC/SDS mixtures show changes in the diffusion time only at room temperature. MC has the tendency to form thermoreversible gel upon heated above 50 °C. The presence of SDS alter the intensity of MC gelation. Before CAC, the addition of SDS promotes the MC gelation. The MC-SDS mixture giving maximum aggregation at room temperature shows decreasing tendency in its diffusion time upon increasing the temperaure. We have shown that a single molecule technique like FCS can be successfully used to follow the dynamics of single aggregates in polymer/surfactant systems. We can identify single inter-chain aggregates, the hydrodynamic size of which changes in a characteristic way as a function of surfactant concentration. These changes are reflected in the behavior of the macroscopic viscosity. The present results show the large potential of single molecule experiments as a complement to the classical macroscopic techniques for a characterization of polymer solutions and polymer/surfactant mixtures. In addition to the large aggregates dominating the macroscopic rheology of the system, the single molecule approach can identify considerably faster aggregates as well, which are not accessible by conventional techniques. Thereby the single molecule approach is able to monitor what may be called a micro viscosity of the solution, i.e. the potential of small aggregates to diffuse rather fast through a network of slowly diffusing chains. This study also shows that the diffusion behavior of polymer-surfactant systems can be followed by FCS without covalent labeling with dye molecules. Moreover, FCS is only sensitive to the dye concentration; therefore these investigations can be applied over a wide range of polymer concentrations.
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Trade unions and the informal economy in Zambia: Building strength or loosing ground?
(2007)
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Georg Heidenreich
- The increasing casualisation of labour forces trade unions globally to deal with a growing number of unprotected and unrepresented workers in what is dubbed by the unions, even if critically, as the informal economy. This paper assesses the impact and further potential of a direct and indirect intervention of the Zambian labour movement towards the informal economy, according to basic criteria like skills development, networking, innovation capacity and access to finance for micro-entrepreneurs. Through providing business development services, the unions also encourage informal sector organizations to associate themselves with Zambia Congress of Trade Unions (ZCTU), thereby strengthening the socio-political representation of the informal economy workers and the labour union movement as a whole. It still remains to be seen, however, to which extent NGO-like approaches that seem to be vital when opening towards the informal economy might compromise basic principles of the labour movement like effective, yet democratic and transparent structures based on mass membership.
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(Na,K) Aluminosilicate Hollandites: Structures, Crystal Chemistry, and High-pressure Behaviour
(2007)
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Jun Liu
- Aluminosilicates with the composition (Na,K)AlSi3O8 and the dense hollandite-type structure, in which all Si and Al are in six-fold coordination, are considered as a possible repository of potassium and sodium in the Earth´s mantle. The aim of this research is to explore the phase relation of the K-Na system at different temperatures and pressures, and to determine the physical-chemical properties and high-pressure behaviour of silicate hollandite-type structures containing K and Na in different concentrations. The (Na,K)AlSi3O8 hollandite solid solution has been synthesised using multi-anvil apparatus in the pressure range between 13 and 26 GPa and temperatures between 1500 and 2200 °C, using (Na0-0.6, K1-0.4)AlSi3O8 glasses, NaAlSi3O8 glass, and Na0.75K0.05Ca0.1AlSi3O8 glass as starting materials. The solubility of Na component into the KAlSi3O8 hollandite end-member increases with increasing pressure and temperature. Homogeneous assemblages with a pure hollandite phase (and maximum 1-2% of stishovite) were synthesized at temperature of 1700 °C and different pressures with up to 50% of NaAlSi3O8 component. No pure NaAlSi3O8 hollandite end-member was succsessfully synthesized. Considering the difference in heat dissipation between the shock events in meteorites and the multi-anvil presses, it appears likely that NaAlSi3O8 hollandite forms as a result of local high pressure and high temperature conditions and really fast quenching under non-equilibrium conditions. All synthesized hollandite samples have tetragonal I4/m symmetry at ambient conditions. The unit-cell volume and lattice parameters of the (Na,K)AlSi3O8 hollandite decreases linearly with increasing Na content. The a cell parameter decreases more rapidly than the c cell parameter, suggesting that changing the cation size in the tunnels of the hollandite structure affects more the a axis than the c axis. Structural refinements of single-crystal data collected for KAlSi3O8 and K0.8Na0.2AlSi3O8 hollandites are consistent with Si and Al disorder among the octahedral sites. The major difference between the KAlSi3O8 hollandite end-member and the K0.8Na0.2AlSi3O8 sample is the presence in the latter of a split site away from the 4th-fold axis. This position, occupied by ~ 75% of the total Na content, is closer to the framework walls and has a very distorted coordination polyhedron with only 5 Na1-O bond distances between 2.4 and 2.6 Angström whereas all other Na1-O bond distances are larger than 3 Angström. The high pressure behaviour of hollandite samples with compositions of KAlSi3O8, K0.8Na0.2AlSi3O8, K0.6Na0.4AlSi3O8, and K0.5Na0.5AlSi3O8 have been studied using diamond anvil cells and different pressure transmitting media, by means of X-ray powder diffraction and Raman spectroscopy. High temperature behaviour of K0.5Na0.5AlSi3O8 hollandite at high pressures has also been explored by means of X-ray powder diffraction. At high pressures, all tetragonal hollandite samples transform to a monoclinic (hollandite II) structure with space group I2/m. The transition pressure decreases with increasing Na component. Na substitution, thus, stabilizes the monoclinic phase, likely because the framework walls are more distorted than in the tetragonal phase and therefore more apt to accommodate the smaller Na atom. Second order Birch- Murnaghan equations of state were calculated for the tetragonal and monoclinic phases. If only experiments using He as pressure transmitting medium are compared, it appears that Na has little effect on the bulk modulus value of the tetragonal aluminosilicate hollandite, but increases the axial anisotropy. Monoclinic hollandites are more compressible, and are stable up to the highest pressures reached during the experiments, suggesting that they may be possible host minerals for Na and K in transition zone and even down to the Earth´s lower mantle. The lattice strains associated with the tetragonal I4/m to monoclinic I2/m transition have been determined. The phase transition is proper ferroelastic with negligible volume strain. The symmetry breaking strains e1-e2=a-b/a0 and e6=a/a0 x cos gamma are proportional to the order parameter Q associated with the transition and their squared values vary linearly with pressure indicating that the transition is second-order in character. The variation with pressure of the symmetry breaking strains is similar in K0.8Na0.2AlSi3O8 and KAlSi3O8 hollandites, suggesting that Na substitution mainly affects the transition pressure but not the transition mechanism. Results from the high pressure experiments show that the tetragonal to monoclinic phase transition is very sensitive to deviatoric stresses present during the experiments due to the different pressure transmitting media. These results might also give an indication of the possible effects arising from stresses on the mineral transitions in the Earth´s mantle.
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Nilmanifolds: complex structures, geometry and deformations
(2007)
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Sönke Rollenske
- We consider nilmanifolds with left-invariant complex structure and prove that in the generic case small deformations of such structures are again left-invariant. The relation between nilmanifolds and iterated principal holomorphic torus bundles is clarified and we give criteria under which deformations in the large are again of such type. As an application we obtain a fairly complete picture in dimension three. We show by example that the Frölicher spectral sequence of a nilmanifold may be arbitrarily non degenerate thereby answering a question mentioned in the book of Griffith and Harris. On our way we prove Serre Duality for Lie algebra Dolbeault cohomology and classify complex structures on nilpotent Lie algebras with small commutator subalgebra. MS Subject classification: 32G05; (32G08, 17B30, 53C30, 32C10)
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High-pressure and high-temperature structural and electronic properties of (Mg,Fe)O and FeO
(2007)
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Innokentiy Kantor
- Magnesium-rich MgO-FeO solid solution, known as the mineral ferropericlase, constitutes a significant part of the Earth as the second most abundant mineral in the lower mantle after (Mg,Fe)SiO3 perovskite. A combined experimental and theoretical study was carried out in order to determine structural and electronic properties of ferropericlase over a broad pressure and temperature range. The phase diagram of FeO (wüstite), the end member of the (Mg,Fe)O solid solution, was found to be more complex than previously thought. It was discovered that the magnetic ordering (Néel) transition does not coincide with the structural cubic-to-trigonal symmetry breaking transition in non-stoichiometric FeO. The magnetic ordering transition was determined for the first time by a combined Mössbauer spectroscopy and neutron diffraction study. A full agreement between these two methods was observed, indicating that in the case of FeO the Mössbauer spectra reflect long-range magnetic ordering. A quasi-single crystal X-ray diffraction study of FeO compared with previous results shows that the transition pressure depends not only on stress conditions, but also on wüstite composition, and probably the order of the transition (second- or weak first-order) is also stress dependent. Above ~70 GPa after laser annealing the X-ray diffraction pattern of FeO could not be explained as a trigonal structure, but as a monoclinic structure with space group P21/m. (Mg,Fe)O solid solution was studied over a wide pressure and temperature range and over a compositional range from 5 to 20 mole % of FeO component. The detailed analysis of (Mg,Fe)O Mössbauer spectra shows clear evidence for the distribution of the hyperfine parameter quadrupole splitting (D), which provides a key to determining its local structure. It is shown that by analyzing the D distribution, a short-range order parameter could be estimated for the low-Fe (Mg,Fe)O solid solution. Samples quenched from high temperature at ambient pressure during synthesis show local cation distribution close to randomness, as was reported previously. Upon compression, however, a rapid increase of short-range order with the tendency for Fe clusterization was observed. This non-random atomic distribution was shown to be stable at high pressures and also at high temperatures. Such a tendency for Fe ions to separate could lead to the miscibility gap in the (Mg,Fe)O solid solution series at high pressures and temperatures, as was observed. At pressures higher than 50 GPa a spin-pairing transition of Fe2+ was observed. Clear and pronounced changes in the Mössbauer spectra are fully consistent with a high- to low-spin transition: the centre shift decreases, indicating an increase of electron density at the nuclei. Quadrupole splitting also vanishes to zero, indicating significant spherical symmetrisation of the valence electrons and electrical field gradient disappearance. The absolute magnitude of these changes is in full agreement with ab initio calculations made in this study. The onset of the spin transition is similar for all the samples studied, but the width is strongly composition dependent. The higher the iron content, the broader the transition width, which reaches about 50 GPa for the (Mg0.8Fe0.2)O sample. Such a broad transition range is not typical for phase transitions with significant volume collapse. Analysis of literature data together with the results of this study lead to an interpretation of spin crossover as a thermal equilibrium process without phase transition. The compositional and temperature dependence of spin crossover in ferropericlase can be described fairly well within such a model, taking into account the local structure of the solid solution. The results of this model were also confirmed by ab initio simulations. The model proposed in this work predicts that spin crossover in ferropericlase will occur over a large depth range of the lower mantle. No discontinuities in density or elastic properties are expected to be produced in the lower mantle due to spin crossover in ferropericlase, contrary to previous suggestions.
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Zwei auf einen Streich: Optimierte dynamische Einsatzplanung für Gelbe Engel und Lastenaufzüge
(2007)
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Jörg Rambau
Cornelius Schwarz
- Wir modellieren zwei verschiedene dynamische Einsatzplanungsprobleme: die dynamische Einsatzplanung Gelber Engel beim ADAC und die Steuerung von Lastenaufzügen in einem Versandlager der Herlitz PBS AG. Wir benutzen eine Reoptimierungspolitik, die die Steuerung des Systems mit Hilfe der Lösung von statischen Schnappschussproblemen durchführt. Für die auftretenden Schnappschussprobleme vergleichen wir zwei Modellierungsansätze (Flussmodell versus Tourenmodell), von denen nur einer echtzeittauglich ist. Das Verfahren zur dynamischen Einsatzplanung Gelber Engel ist beim ADAC in Betrieb.
