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Existing theoretical literature fails to explain satisfactorily the differences between the pay of workers that are covered by collective agreements and others who are not. This study aims at providing a model framework which is amenable for an analysis of this issue. Our general-equilibrium approach integrates a dual labor market and a two-sector product market. The results suggest that the so-called 'union wage gap' is largely determined by the degree of centralization of the bargains, and, to a somewhat lesser extent, by the expenditure share of the unionized sector's goods.
Unity in diversity
(2005)
This paper describes the creation and preparation of TUSNELDA, a collection of corpus data built for linguistic research. This collection contains a number of linguistically annotated corpora which differ in various aspects such as language, text sorts / data types, encoded annotation levels, and linguistic theories underlying the annotation. The paper focuses on this variation on the one hand and the way how these heterogeneous data are integrated into one resource on the other hand.
Multiple hierarchies
(2005)
In this paper, we present the Multiple Annotation approach, which solves two problems: the problem of annotating overlapping structures, and the problem that occurs when documents should be annotated according to different, possibly heterogeneous tag sets. This approach has many advantages: it is based on XML, the modeling of alternative annotations is possible, each level can be viewed separately, and new levels can be added at any time. The files can be regarded as an interrelated unit, with the text serving as the implicit link. Two representations of the information contained in the multiple files (one in Prolog and one in XML) are described. These representations serve as a base for several applications.
Fronting of an infinite VP across a finite main verb-akin to German "VP-topicalization"-can be found also in Czech and Polish. The paper discusses evidence from large corpora for this process and some of its properties, both syntactic and information-structural. Based on this case, criteria for more user-friedly searching and retrieval of corpus data in syntactic research are being developed.
The Semantics of Ellipsis
(2005)
There are four phenomena that are particularly troublesome for theories of ellipsis: the existence of sloppy readings when the relevant pronouns cannot possibly be bound; an ellipsis being resolved in such a way that an ellipsis site in the antecedent is not understood in the way it was there; an ellipsis site drawing material from two or more separate antecedents; and ellipsis with no linguistic antecedent. These cases are accounted for by means of a new theory that involves copying syntactically incomplete antecedent material and an analysis of silent VPs and NPs that makes them into higher order definite descriptions that can be bound into.
It is predicted that Service-oriented Architectures (SOA) will have a high impact on future electronic business and markets. Services will provide an self-contained and standardised interface towards business and are considered as the future platform for business-to-business and business-toconsumer trades. Founded by the complexity of real world business scenarios a huge need for an easy, flexible and automated creation and enactment of service compositions is observed. This survey explores the relationship of service composition with workflow management—a technology/ concept already in use in many business environments. The similarities between the both and the key differences between them are elaborated. Furthermore methods for composition of services ranging from manual, semi- to full-automated composition are sketched. This survey concludes that current tools for service composition are in an immature state and that there is still much research to do before service composition can be used easily and conveniently in real world scenarios. However, since automated service composition is a key enabler for the full potential of Service-oriented Architectures, further research on this field is imperative. This survey closes with a formal sample scenario presented in appendix A to give the reader an impression on how full-automated service composition works.
The article provides historical background for Alexander von Humboldt’s expedition into Russia in 1829. It includes information on Humboldt’s works and publications in Russia over the course of his lifetime, as well as an explanation of the Russian scientific community’s response to those works. Humboldt’s ideas on the existence of an active volcano in Central Asia attracted the attention of two prominent Russian geographers, P. Semenov and P. Kropotkin, whose views on the nature of volcanism were quite different. P. Semenov personally met Humboldt in Berlin. P. Kropotkin made one of the most important geological discoveries of the 19th Century: he found the fresh volcanic cones near Lake Baikal.
Soon after Humboldt’s Russian expedition, and partly as a result of it, an important mineral was found in the Ilmen mountains – samarskite, which later gave its name to the chemical element Samarium, developed in 1879. At the beginning of the 20th Century, the Russian scientist V. Vernadskiy pointed out that samarskite was the first uranium-rich mineral found in Russia.
Stephen Jay Gould wrote recently that “when Church began to paint his great canvases, Alexander von Humboldt may well have been the world’s most famous and influential intellectual.” Humboldt’s influence in the case of the landscape artist Church is especially interesting. If we examine the precise relationship between the German explorer and his American admirer, we gain an insight into how Humboldt transformed Church’s life and signaled a new phase in the career of the artist. Church retraced Humboldt’s travels in Ecuador and in Mexico. If we compare the texts available to Church and the comparison of Church’s paintings and the texts and images of Humboldt’s works we can arrive at new perspectives on Humboldt’s extraordinary influence on American landscape painting in the nineteenth century.
Alexander von Humboldt’s descriptions of volcanic mountains in his travel journals (Reise auf dem Río Magdalena, durch die Anden und Mexico) show both his reliance on and impatience with literary conventions and travel narratives. Using Goethe’s Italienische Reise and Bürger’s Münchhausen as points of comparison for literary treatments of the volcano ascent, Humboldt’s process of writing is examined. Humboldt shows the failure of the existing discourse and begins to experiment with narratives which fragment and recombine personal and historical modes of writing with, in this case, images from new technical inventions which visualize landscape according to fundamental scientific principles. While the inclusion of scientific prose is relevant, Humboldt’s link to modernity is based on experimental narrative techniques which draw upon changing sets of discourse practices to describe complex realities.
The Humboldt Digital Library
(2005)
Alexander von Humboldt’s maps, graphs and illustrations contain a great deal of detail, but in the available rare editions they are hardly visible to the naked eye. In many editions they have been reduced. In a digital library, they will become accessible in their entirety, and Internet technology will reproduce them in a form that overcomes the limitations of the original printing. The user will be able to enlarge the images and see details that might have been overlooked in the past. The Humboldt’s digital library will adhere to the standards for digital libraries established by the Open Archives Initiative (OAI) and the tools EPRINTS and DSPACE to provide the Web services and determine the most effective way to establish dynamic linking and knowledge based searching of information within the archive.
To determine whether Förster resonance energy transfer (FRET) measurements can provide quantitative distance information in single-molecule fluorescence experiments on polypeptides, we measured FRET efficiency distributions for donor and acceptor dyes attached to the ends of freely diffusing polyproline molecules of various lengths. The observed mean FRET efficiencies agree with those determined from ensemble lifetime measurements but differ considerably from the values expected from Förster theory, with polyproline treated as a rigid rod. At donor–acceptor distances much less than the Förster radius R0, the observed efficiencies are lower than predicted, whereas at distances comparable to and greater than R0, they are much higher. Two possible contributions to the former are incomplete orientational averaging during the donor lifetime and, because of the large size of the dyes, breakdown of the point-dipole approximation assumed in Förster theory. End-to-end distance distributions and correlation times obtained from Langevin molecular dynamics simulations suggest that the differences for the longer polyproline peptides can be explained by chain bending, which considerably shortens the donor–acceptor distances.
Absorption and fluorescence properties of 4 hydraulic oils (3 biological and 1 petroleum-based) were investigated. In-situ LIF (laser-induced fluorescence) analysis of the oils on a brown sandy loam soil was performed. With calibration, quantitative detection was achieved. Estimated limits of detection were below ca. 500 mg/kg for the petroleum-based oil and ca. 2000 mg/kg for one biological oil. A semi-quantitative classification scheme is proposed for monitoring of the biological oils. This approach was applied to investigate the migration of a biological oil in soil-containing compartments, namely a soil column and a soil bed.
The interactions between peptides and lipids are of fundamental importance in the functioning of numerous membrane-mediated biochemical processes including antimicrobial peptide action, hormone-receptor interactions, drug bioavailability across the blood-brain barrier and viral fusion processes. Alteration of peptide structure could be a cause of many diseases. Biological membranes are complex systems, therefore simplified models may be introduced in order to understand processes occurring in nature. The lipid monolayers at the air/water interface are suitable model systems to mimic biological membranes since many parameters can be easily controlled. In the present work the lipid monolayers were used as a model membrane and their interactions with two different peptides B18 and Amyloid beta (1-40) peptide were investigated. B18 is a synthetic peptide that binds to lipid membranes that leads to the membrane fusion. It was demonstrated that it adopts different structures in the aqueous solutions and in the membrane interior. It is unstructured in solutions and forms alpha-helix at the air/water interface or in the membrane bound state. The peptide has affinity to the negatively charged lipids and even can fold into beta-sheet structure in the vicinity of charged membranes at high peptide to lipid ratio. It was elucidated that in the absence of electrostatic interactions B18 does not influence on the lipid structure, whereas it provides partial liquidization of the negatively charged lipids. The understanding of mechanism of the peptide action in model system may help to develop the new type of antimicrobial peptides as well as it can shed light on the general mechanisms of peptide/membrane binding. The other studied peptide - Amyloid beta (1-40) peptide, which is the major component of amyloid plaques found in the brain of patients with Alzheimer's disease. Normally the peptide is soluble and is not toxic. During aging or as a result of the disease it aggregates and shows a pronounced neurotoxicity. The peptide aggregation involves the conformational transition from a random coil or alpha-helix to beta-sheets. Recently it was demonstrated that the membrane can play a crucial role for the peptide aggregation and even more the peptide can cause the change in the cell membranes that leads to a neuron death. In the present studies the structure of the membrane bound Amyloid beta peptide was elucidated. It was found that the peptide adopts the beta-sheet structure at the air/water interface or being adsorbed on lipid monolayers, while it can form alpha-helical structure in the presence of the negatively charged vesicles. The difference between the monolayer system and the bulk system with vesicles is the peptide to lipid ratio. The peptide adopts the helical structure at low peptide to lipid ratio and folds into beta-sheet at high ratio. Apparently, Abeta peptide accumulation in the brain is concentration driven. Increasing concentration leads to a change in the lipid to peptide ratio that induces the beta-sheet formation. The negatively charged lipids can act as seeds in the plaque formation, the peptide accumulates on the membrane and when the peptide to lipid ratio increases it the peptide forms toxic beta-sheet containing aggregates.
For interactive construction of CSG models understanding the layout of a model is essential for its efficient manipulation. To understand position and orientation of aggregated components of a CSG model, we need to realize its visible and occluded parts as a whole. Hence, transparency and enhanced outlines are key techniques to assist comprehension. We present a novel real-time rendering technique for visualizing design and spatial assembly of CSG models. As enabling technology we combine an image-space CSG rendering algorithm with blueprint rendering. Blueprint rendering applies depth peeling for extracting layers of ordered depth from polygonal models and then composes them in sorted order facilitating a clear insight of the models. We develop a solution for implementing depth peeling for CSG models considering their depth complexity. Capturing surface colors of each layer and later combining the results allows for generating order-independent transparency as one major rendering technique for CSG models. We further define visually important edges for CSG models and integrate an image-space edgeenhancement technique for detecting them in each layer. In this way, we extract visually important edges that are directly and not directly visible to outline a model’s layout. Combining edges with transparency rendering, finally, generates edge-enhanced depictions of image-based CSG models and allows us to realize their complex, spatial assembly.
In order to characterise the C*-algebra generated by the singular Bochner-Martinelli integral over a smooth closed hypersurfaces in Cn, we compute its principal symbol. We show then that the Szegö projection belongs to the strong closure of the algebra generated by the singular Bochner-Martinelli integral.
The aim of this paper is to explain the notion of subspace defined by means of pseudodifferential projection and give its applications in elliptic theory. Such subspaces are indispensable in the theory of well-posed boundary value problems for an arbitrary elliptic operator, including the Dirac operator, which has no classical boundary value problems. Pseudodifferential subspaces can be used to compute the fractional part of the spectral Atiyah–Patodi–Singer eta invariant, when it defines a homotopy invariant (Gilkey’s problem). Finally, we explain how pseudodifferential subspaces can be used to give an analytic realization of the topological K-group with finite coefficients in terms of elliptic operators. It turns out that all three applications are based on a theory of elliptic operators on closed manifolds acting in subspaces.
We consider a boundary value problem for an elliptic differential operator of order 2m in a domain D ⊂ n. The boundary of D is smooth outside a finite number of conical points, and the Lopatinskii condition is fulfilled on the smooth part of δD. The corresponding spaces are weighted Sobolev spaces H(up s,Υ)(D), and this allows one to define ellipticity of weight Υ for the problem. The resolvent of the problem is assumed to possess rays of minimal growth. The main result says that if there are rays of minimal growth with angles between neighbouring rays not exceeding π(Υ + 2m)/n, then the root functions of the problem are complete in L²(D). In the case of second order elliptic equations the results remain true for all domains with Lipschitz boundary.