264 research outputs found
A bag of useful techniques for efficient and robust parsing
This paper describes new and improved techniques which help a unification-based parser to process input efficiently and robustly. We show that combining these methods leads to a speed-up in parsing time of more than an order of magnitude. The methods are correct in the sense that none of them rule out legal rule applications
An integrated architecture for shallow and deep processing
We present an architecture for the integration of shallow and deep NLP components which is aimed at flexible combination of different language technologies for a range of practical current and future applications. In particular, we describe the integration of a high-level HPSG parsing system with different high-performance shallow components, ranging from named entity recognition to chunk parsing and shallow clause recognition. The NLP components enrich a representation of natural language text with layers of new XML meta-information using a single shared data structure, called the text chart. We describe details of the integration methods, and show how information extraction and language checking applications for realworld German text benefit from a deep grammatical analysis
A bag of useful techniques for efficient and robust parsing
This paper describes new and improved techniques which help a unification-based parser to process input efficiently and robustly. We show that combining these methods leads to a speed-up in parsing time of more than an order of magnitude. The methods are correct in the sense that none of them rule out legal rule applications
An HSPG-to-CFG Approximation of Japanese
We present a simple approximation method for turning a Head-Driven Phrase Structure Grammar into a context-free grammar. The approximation method can be seen as the construction of the least fixpoint of a certain monotonic function. We discuss an experiment with a large HPSG for Japanese
Placental Syncytiotrophoblast Maintains a Specific Type of Glycocalyx at the Fetomaternal Border: The Glycocalyx at the Fetomaternal Interface in Healthy Women and Patients With HELLP Syndrome
Recent studies showed that considerable amounts of glycosaminoglycans are released into maternal blood during normal pregnancy and in hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome. Maternal endothelia and the syncytiotrophoblast layer have been discussed as a possible origin of these glycocalyx components. Our study aimed to visualize the glycocalyx on the syncytiotrophoblast by electron microscopy, to analyze its structure and composition by immunohistochemistry, and to determine potential differences between healthy women and women with HELLP syndrome. For electron microscopy, a cotyledon was fixed by perfusion of the intervillous space with a 2% lanthanum-nitrate glutaraldehyde solution followed by immersion fixation in the same fixative. For immunohistochemistry, sections of 16 placentas (HELLP patients/healthy women, n = 8 each) were stained with monoclonal antibodies against the main glycocalyx constituents syndecan 1, hyaluronic acid, and heparan sulfate. Semiquantitative evaluation of staining intensity focused on the apical surface of the syncytiotrophoblast and fetal intravillous endothelia as possible localizations of a placental glycocalyx. Electron microscopy revealed a glycocalyx of approximately 250nm, covering the syncytiotrophoblast layer. This was found to contain large amounts of syndecan 1, but neither hyaluronic acid nor heparan sulfate as major components. Intravillous fetal endothelium did not express any of the investigated glycosaminoglycans. Healthy women and patients with HELLP showed no differences concerning glycocalyx composition and thickness of the syncytiotrophoblast. The composition of the placental glycocalyx differs from the adult and fetal vascular glycocalyx. Obviously, the human placental syncytiotrophoblast maintains a special kind of glycocalyx at the fetomaternal interface
Placental Syncytiotrophoblast Maintains a Specific Type of Glycocalyx at the Fetomaternal Border: The Glycocalyx at the Fetomaternal Interface in Healthy Women and Patients With HELLP Syndrome
Recent studies showed that considerable amounts of glycosaminoglycans are released into maternal blood during normal pregnancy and in hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome. Maternal endothelia and the syncytiotrophoblast layer have been discussed as a possible origin of these glycocalyx components. Our study aimed to visualize the glycocalyx on the syncytiotrophoblast by electron microscopy, to analyze its structure and composition by immunohistochemistry, and to determine potential differences between healthy women and women with HELLP syndrome. For electron microscopy, a cotyledon was fixed by perfusion of the intervillous space with a 2% lanthanum-nitrate glutaraldehyde solution followed by immersion fixation in the same fixative. For immunohistochemistry, sections of 16 placentas (HELLP patients/healthy women, n = 8 each) were stained with monoclonal antibodies against the main glycocalyx constituents syndecan 1, hyaluronic acid, and heparan sulfate. Semiquantitative evaluation of staining intensity focused on the apical surface of the syncytiotrophoblast and fetal intravillous endothelia as possible localizations of a placental glycocalyx. Electron microscopy revealed a glycocalyx of approximately 250nm, covering the syncytiotrophoblast layer. This was found to contain large amounts of syndecan 1, but neither hyaluronic acid nor heparan sulfate as major components. Intravillous fetal endothelium did not express any of the investigated glycosaminoglycans. Healthy women and patients with HELLP showed no differences concerning glycocalyx composition and thickness of the syncytiotrophoblast. The composition of the placental glycocalyx differs from the adult and fetal vascular glycocalyx. Obviously, the human placental syncytiotrophoblast maintains a special kind of glycocalyx at the fetomaternal interface
Coordinates, observables and symmetry in relativity
We investigate the interplay and connections between symmetry properties of
equations, the interpretation of coordinates, the construction of observables,
and the existence of physical relativity principles in spacetime theories.
Using the refined notion of an event as a ``point-coincidence'' between scalar
fields that completely characterise a spacetime model, we also propose a
natural generalisation of the relational local observables that does not
require the existence of four everywhere invertible scalar fields. The
collection of all point-coincidences forms in generic situations a
four-dimensional manifold, that is naturally identified with the physical
spacetime.Comment: 37 page
Is there a relativistic nonlinear generalization of quantum mechanics?
Yes, there is. - A new kind of gauge theory is introduced, where the minimal
coupling and corresponding covariant derivatives are defined in the space of
functions pertaining to the functional Schroedinger picture of a given field
theory. While, for simplicity, we study the example of an U(1) symmetry, this
kind of gauge theory can accommodate other symmetries as well. We consider the
resulting relativistic nonlinear extension of quantum mechanics and show that
it incorporates gravity in the (0+1)-dimensional limit, where it leads to the
Schroedinger-Newton equations. Gravity is encoded here into a universal
nonlinear extension of quantum theory. The probabilistic interpretation, i.e.
Born's rule, holds provided the underlying model has only dimensionless
parameters.Comment: 10 pages; talk at DICE 2006 (Piombino, September 11-15, 2006); to
appear in Journal of Physics: Conference Series (2007
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