671 research outputs found
Transfer and Multi-Task Learning for Noun-Noun Compound Interpretation
In this paper, we empirically evaluate the utility of transfer and multi-task
learning on a challenging semantic classification task: semantic interpretation
of noun--noun compounds. Through a comprehensive series of experiments and
in-depth error analysis, we show that transfer learning via parameter
initialization and multi-task learning via parameter sharing can help a neural
classification model generalize over a highly skewed distribution of relations.
Further, we demonstrate how dual annotation with two distinct sets of relations
over the same set of compounds can be exploited to improve the overall accuracy
of a neural classifier and its F1 scores on the less frequent, but more
difficult relations.Comment: EMNLP 2018: Conference on Empirical Methods in Natural Language
Processing (EMNLP
Implications of a temperature-dependent magnetic anisotropy for superparamagnetic switching
The macroscopic magnetic moment of a superparamagnetic system has to overcome
an energy barrier in order to switch its direction. This barrier is formed by
magnetic anisotropies in the material and may be surmounted typically after
10^9 to 10^12 attempts per second by thermal fluctuations. In a first step, the
associated switching rate may be described by a Neel-Brown-Arrhenius law, in
which the energy barrier is assumed as constant or a given temperature. Yet,
magnetic anisotropies in general depend on temperature themselves which is
known to modify the Neel-Brown-Arrhenius law. We illustrate quantitatively the
implications of a temperature-dependent anisotropy on the switching rate and in
particular for the interpretation of the prefactor as an attempt frequency. In
particular, we show that realistic numbers for the attempt frequency are
obtained when the temperature dependence of the anisotropy is taken into
account.Comment: 15 pages, 5 figure
Parallel Distributed Grammar Engineering for Practical Applications
Based on a detailed case study of parallel grammar development distributed across two sites, we review some of the requirements for regression testing in grammar engineering, summarize our approach to systematic competence and performance profiling, and discuss our experience with grammar development for a commercial application. If possible, the workshop presentation will be organized around a software demonstration
Novel insights into the regulation of nucleolar function and longevity by ncl-1
The nucleolus is primarily described as the control center for ribonuclear protein assembly and rRNA synthesis. However, there is increasing evidence that the nucleolus also plays a role in protein quality, genome stability and cell cycle progression. Previous studies demonstrated that the B-box type zinc finger protein ncl- 1 is tightly linked to nucleolar function, and that its loss leads to increased levels of the nucleolar marker fibrillarin (fib-1) and to an increased nucleolar area. These nucleolar phenotypes are accompanied by the abolishment of lifespan extension in the major longevity pathways. However, the molecular connection between ncl-1, nucleolar function and longevity remains elusive.
To identify molecular players and pathways that mediate the function of ncl-1 on longevity, I performed transcriptomic and proteomic analysis, comparing wild-type worms to ncl-1 worms in normal as well as the long-lived glp-1 background. This analysis revealed some shared and some background-specific regulation of distinct biological pathways upon loss of ncl-1: While nuclear outputs such as ribosome biogenesis and rRNA production are increased in multiple tested genotypes, proteasomal components are decreased in ncl-1 single mutants, while lysosomal components show lower abundance in glp-1;ncl-1. Interestingly, NCL-1 seems to affect at least a portion of regulated genes through direct binding of respective mRNAs. Based on transcriptomic and proteomic data, I conducted a follow-up RNA interference screen of potential mediators and uncovered nucleolar downstream processes of ncl- 1 including the RNase P/MRP complex and mitochondrial translation. Knockdown of the shared RNase P/MRP component POPL-1 as well as other RNase P/MRP factors extended lifespan in glp-1;ncl-1 mutants. The same was observed for other rRNA processing and ribosome assembly factors as well as proteins involved in mitochondrial translation such as MRPS-16. Reduction of popl-1 and mrps-16 extended lifespan independent of nucleolar size, fib-1 mRNA levels or steady state rRNA levels, thereby uncoupling nucleolar size from lifespan for the first time. Also, overall translation rate seems unaffected. Thus, the effect of NCL-1 on lifespan may
be mediated through altered ribosome assembly in glp-1 worms, while being unaffected in the N2 background.
To further investigate the molecular mechanism of NCL-1 action, I conducted a Yeast- 2-Hybrid assay and pulldown experiments to identify NCL-1 protein interactors. In a mini RNAi screen, I found that a reduction of the potential NCL-1 interactor and proteasomal factor RPN-11 affects nucleolar size in glp-1 mutants, indicating a direct connection of NCL-1 to the proteasome. In line with this, ncl-1 affects cellular proteostasis with the proteasome as a presumable key player, as ncl-1 mutants are short-lived under modest thermal stress and are less motile. In addition, I observed that overall ubiquitinylation levels are increased, and that proteasome substrates accumulate in ncl-1 mutants.
In the pulldown experiments with NCL-1, I identified several mitochondrial factors in the co-enriched fraction of NCL-1. I also found that NCL-1 forms round network-like structures and strong foci resembling mitochondria within the hypodermis and muscle, further supporting a mitochondrial connection.
Further on I established a connection between the RNAi machinery, nucleolar size and lifespan with a central focus on the argonaut protein NRDE-3 being required for longevity and affecting nucleolar size.
Using a range of genetic and biochemical approaches, I found that ncl-1 is a multifaceted gene that connects multiple important cellular pathways with a focus on nucleolar outputs, but also proteolytic processes. I identified the RNase P/MRP complex and mitochondrial translation as potential key processes for mediating the function of ncl-1 in longevity
Imaging of Magnetic Microstructures at Surfaces: The Scanning Electron Microscope with Spin Polarization Analysis
The scanning electron microscope with spin polarization analysis of secondary electrons has been proven to be a powerful tool for studying magnetic microstructures. Secondary electrons created at the surface of a ferromagnet are spin-polarized and contain information about the sample magnetization and its orientation. The combination of a spin polarization analyzer with a scanning electron microscope yields an unique apparatus for probing magnetic properties on a very small lateral scale. The magnetic resolution of \u3c 40 nm is demonstrated. This type of microscope provides high magnetic contrast, while the surface morphology is strongly or even totally suppressed. The capability of studying magnetic properties of semi- infinite samples as well as in ultrathin films is demonstrated with a Fe(lOO) single crystal, video tape, CoCr perpendicular recording medium and ultrathin cobalt films
DRS at MRP 2020:Dressing up Discourse Representation Structures as Graphs
Discourse Representation Theory (DRT) is a formal account for representing
the meaning of natural language discourse. Meaning in DRT is modeled via a
Discourse Representation Structure (DRS), a meaning representation with a
model-theoretic interpretation, which is usually depicted as nested boxes. In
contrast, a directed labeled graph is a common data structure used to encode
semantics of natural language texts. The paper describes the procedure of
dressing up DRSs as directed labeled graphs to include DRT as a new framework
in the 2020 shared task on Cross-Framework and Cross-Lingual Meaning
Representation Parsing. Since one of the goals of the shared task is to
encourage unified models for several semantic graph frameworks, the conversion
procedure was biased towards making the DRT graph framework somewhat similar to
other graph-based meaning representation frameworks.Comment: 10 pages, 4 figures, 4 tables, CoNLL 2020 Shared Tas
The Grammar Matrix: An Open-Source Starter-Kit for the Rapid Development of Cross-Linguistically Consistent Broad-Coverage Precision Grammars
The grammar matrix is an open-source starter-kit for the development of broadcoverage HPSGs. By using a type hierarchy to represent cross-linguistic generalizations and providing compatibility with other open-source tools for grammar engineering, evaluation, parsing and generation, it facilitates not only quick start-up but also rapid growth towards the wide coverage necessary for robust natural language processing and the precision parses and semantic representations necessary for natural language understanding
Phasenorientiertes Bauprojekt-Controlling in bauausführenden Unternehmen: unter besonderer Berücksichtigung einer zweigliedrigen Arbeitskalkulation
Bauausführende Unternehmen sind in der anhaltenden Konjunktur- und Strukturkrise gefordert, ein effizientes System des Bauprojekt-Controlling aufzubauen. Diese Dissertation beschreibt hierzu ein phasenorientiertes System des Bauprojekt-Controlling, dessen Elemente und Aufgaben - vor der Bauausführung auf eine Optimierung der Planungsaktivitäten im Sinne einer systematischen Vorbereitung der späteren Bauausführung ausgerichtet sind; - während der Bauausführung aufbauend auf vergangenheitsorientierten Kontroll- und Analyserechnungen eine auf das Ausführungsende ausgerichtete zukunftsdisponierende Steuerung des Bauprojektes ermöglicht; - nach der Bauausführung eine Analyse des soeben fertig gestellten Bauprojektes durchführt, um so zu aktualisierten Vorgabewerten neuer Bauprojekte zu gelangen. Alle Phasen des Bauprojekt-Controlling werden in den beiden Datensichten einer zweigliedrigen Arbeitskalkulation vorbereitet, begleitet, kontrolliert, analysiert und gesteuert
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