Analyse kortikaler Reizantwortsignale nach selektiver Zapfenstimulation zur objektiven Erkennung von Sehfunktionsstörungen

The objective of this thesis was an objective diagnosis of the visual system. Therefore the separate color channels were analyzed by the use of cortical response signals. The potential of the developed method, especially for the detection of glaucoma, was investigated.Based on the silent substitution technique, model based adaptive stimulation sequences were developed, in order to achieve selective color channel excitation. Pre-processing of the response signals, suppression of distortions and improvement of the signal to noise ratio were introduced, adapted and analyzed. Therewith the analysis of the visually evoked potentials was possible.For an objective description and analysis of color channel selective response signals an extensive parameterization of the response signals and validation of the feature set was done. By the use of different classification methods and evaluation strategies, the classification of the separate color channels as well as the classification on a large number glaucoma patients and healthy volunteers was performed, in order to verify the diagnostic significance of the response signals. Furthermore an evaluation of classification quality of the utilized classification methods was performed. Cone isolation could be demonstrated by an adaption and bleaching experiment. The color channel selective response signals were extensively parameterized by means of significant features. Through the use of the different classification methods very good results were achieved in the detection of specific response signals of severe glaucoma patients and in the differentiation of the several color channels. Moreover good classification results were obtained for moderate glaucoma patients. None of the used classification methods demonstrated significant advantages in classification quality.An objective examination of the entire visual system from the retina to the visual cortex was carried out by the measurement and analysis of the visually evoked potentials. It was shown, that an objective examination of the several visual pathways as well as an early objective diagnosis of glaucoma was possible. Hence, objective examinations of color vision respectively color vision deficiencies are conceivable. The presented methods can lead to new diagnostic possibilities.Die vorliegende Arbeit befasst sich mit der objektiven Diagnostik des visuellen Systems, insbesondere der Analyse der Funktion einzelner Farbkanäle, anhand kortikaler Reizantwortsignale. Dabei wird das Potenzial des erarbeiteten Verfahrens speziell zur Erkennung von Glaukomerkrankungen untersucht.Zur farbkanalselektiven Reizung wurden modellbasierte, adaptierbare Stimulationssequenzen auf Grundlage der Silent Substitution Technique entwickelt. Zur Vorverarbeitung der Reizantwortsignale, Unterdrückung von Störkomponenten bzw. Verbesserung des Signal-Rausch-Abstandes wurden verschiedene Verfahren untersucht und adaptiert. Damit konnten die visuell evozierten Potenziale analysiert werden.Die Arbeit beschäftigt sich weiterhin mit der umfangreichen Parametrisierung der Signale sowie einer Bewertung des Merkmalssatzes bezüglich der unterschiedlichen Fragestellungen für die objektive Beschreibung und Analyse der Eigenschaften der farbkanalspezifischen Reizantwortsignale. Mittels verschiedener Klassifikationsverfahren und Evaluierungsstrategien wurden, zur Prüfung der diagnostischen Aussagekraft der Reizantwortsignale, Klassifikationen der einzelnen Farbkanäle sowie von Glaukompatienten im Vergleich zu gesunden Probanden, an einer relativ großen Anzahl von ca. 500 Untersuchungsdaten¬sätzen, vorgenommen. Zudem erfolgte eine Beurteilung der Klassifikations¬qualität der verwendeten Klassifikationsmethoden für die verschiedenen Anwendungen.Ein Funktionsnachweis der Methode zur selektiven Zapfenstimulation konnte anhand eines Adaptions- und Zapfenbleichungsexperiments erbracht werden. Die gewonnenen farbkanalselektiven Antwortsignale wurden mittels signifikanter Merkmale umfassend parametrisiert. Mit verschiedenen Klassifikationsmethoden wurden sehr gute Ergebnisse bei der Erkennung der spezifischen Reizantwortsignale von Glaukompatienten mit schwerem Glaukomschaden sowie bei der Differenzierung einzelner Farbkanäle erzielt. Für Glaukompatienten im frühen Stadium ergaben sich ebenfalls gute Klassifikationsergebnisse. Keine der verwendeten Klassifikationsmethoden zeigten dabei entscheidende Vorteile bezüglich der Klassifikationsqualität.Durch die Messung der visuell evozierten Potenziale im Bereich des visuellen Kortex konnte im Rahmen der Arbeit eine objektive Untersuchung des gesamten visuellen Systems (Retina bis Kortex) durchgeführt werden. Somit war es möglich eine Untersuchung der einzelnen Farbkanäle des visuellen Systems sowie eine objektive frühzeitige Diagnostik von Glaukomerkrankungen durchzuführen. Damit sind auch Untersuchungen des Farbsinns bzw. von Farbfehlsichtigkeiten denkbar. Das vorgestellte Verfahren könnte somit neue diagnostische Möglichkeiten eröffnen

Rapidez y emociones en las locuciones adverbiales españolas : un estudio traductológico, pragmático y fraseográfico español-alemán

El presente artículo estudia las diferencias semántico-pragmáticas existentes entre las numerosas locuciones adverbiales que expresan rapidez en español partiendo de un análisis de su valor emotivo. El análisis tiene lugar sobre la base de ejemplos auténticos procedentes de Internet. También se proponen equivalencias en alemán, fraseológicas o no

El proyecto diccionario español-alemán de locuciones del español de España de Colonia/Hamburgo

Ya han pasado varios años desde que la revista Estudis Romànics tuvo la amabilidad de publicarnos una primera presentación de nuestro proyecto (cf. Torrent-Lenzen 2007), hoy todavía en curso, que consiste en la elaboración de un Diccionario español-alemán de locuciones del español de España. Entre tanto, hemos avanzado considerablemente en nuestro trabajo fraseográfico y también hemos ido modificando nuestros objetivos, con lo cual dicho artículo ha perdido actualidad. Es por esta razón que, estando más o menos “a mitad de camino”, queremos exponer de nuevo, en las páginas que siguen, los rasgos principales de nuestra obra, tal como la concebimos ahora después de que hayan madurado muchas ideas

Towards a Neuronally Consistent Ontology for Robotic Agents

The Collaborative Research Center for Everyday Activity Science & Engineering (CRC EASE) aims to enable robots to perform environmental interaction tasks with close to human capacity. It therefore employs a shared ontology to model the activity of both kinds of agents, empowering robots to learn from human experiences. To properly describe these human experiences, the ontology will strongly benefit from incorporating characteristics of neuronal information processing which are not accessible from a behavioral perspective alone. We, therefore, propose the analysis of human neuroimaging data for evaluation and validation of concepts and events defined in the ontology model underlying most of the CRC projects. In an exploratory analysis, we employed an Independent Component Analysis (ICA) on functional Magnetic Resonance Imaging (fMRI) data from participants who were presented with the same complex video stimuli of activities as robotic and human agents in different environments and contexts. We then correlated the activity patterns of brain networks represented by derived components with timings of annotated event categories as defined by the ontology model. The present results demonstrate a subset of common networks with stable correlations and specificity towards particular event classes and groups, associated with environmental and contextual factors. These neuronal characteristics will open up avenues for adapting the ontology model to be more consistent with human information processing.Comment: Preprint of paper accepted for the European Conference on Artificial Intelligence (ECAI) 2023 (minor typo corrections

Combining a root exclusion technique with continuous measurements of CO2 by chambers and inside soil for a pin-point separation of ecosystem respiration in croplands

To better assess ecosystem C budgets of croplands and understand their potential response to climate and management changes, detailed information on the mechanisms and environmental controls driving the individual C flux components are needed. This accounts in particular for the ecosystem respiration (Reco) and its components, the autotrophic (Ra) and heterotrophic respiration (Rh) which vary tremendously in time and space. Therefore, we developed and tested a method to separate Reco into Ra (as the sum of Ra (shoot) and Ra (root)) and Rh in order to detect temporal and small-scale spatial dynamics within their relative contribution to overall Reco. Investigations were carried out for winter wheat (Triticum aestivum) during the crop season 2015 at an experimental plot (CarboZALF-D) located in the hummocky ground moraine landscape of NE Germany. Reco was derived from CO2 flux measurements from plant stand and soil during nighttime using automatic chambers. Rh was derived from CO2 efflux measurements from fallow next to the automatic chambers using CO2 sampling tubes in 10 cm soil depth. Ra (root) was calculated as the difference between CO2 efflux measurements in planted soil and Rh. Ra (shoot) was calculated as Reco - Ra (root) - Rh. Reco varied seasonally from <1 to 9.5 g C m-2 d-1, and was higher in adult (a) and reproductive (r) than juvenile (j) stands (g C m-2 d-1: j 1.2, a 4.6, r 5.3). Observed Ra and Rh were in general smaller compared to the independently measured Reco, contributing in average 56 % and 44 % to Reco. However, both varied strongly regarding their environmental drivers and particular contribution throughout the study period, following the seasonal development of soil temperature and moisture (Rh) as well as crop development (Ra). Thus, our results consistently revealed temporal dynamics regarding the relative contribution of Ra (root) and Ra (shoot) to Ra, as well as of Ra and Rh to Reco. Based on the observed results, implications for partitioning of Reco in croplands are given, which requires a spatial and temporal pin-point approach to increase reliability

An Ontological Model of User Preferences

The notion of preferences plays an important role in many disciplines including service robotics which is concerned with scenarios in which robots interact with humans. These interactions can be favored by robots taking human preferences into account. This raises the issue of how preferences should be represented to support such preference-aware decision making. Several formal accounts for a notion of preferences exist. However, these approaches fall short on defining the nature and structure of the options that a robot has in a given situation. In this work, we thus investigate a formal model of preferences where options are non-atomic entities that are defined by the complex situations they bring about

An ontology for failure interpretation in automated planning and execution

This is a post-peer-review, pre-copyedit version of an article published in ROBOT - Iberian Robotics Conference. The final authenticated version is available online at: http://dx.doi.org/10.1007/978-3-030-35990-4_31”.Autonomous indoor robots are supposed to accomplish tasks, like serve a cup, which involve manipulation actions, where task and motion planning levels are coupled. In both planning levels and execution phase, several source of failures can occur. In this paper, an interpretation ontology covering several sources of failures in automated planning and also during the execution phases is introduced with the purpose of working the planning more informed and the execution prepared for recovery. The proposed failure interpretation ontological module covers: (1) geometric failures, that may appear when e.g. the robot can not reach to grasp/place an object, there is no free-collision path or there is no feasible Inverse Kinematic (IK) solution. (2) hardware related failures that may appear when e.g. the robot in a real environment requires to be re-calibrated (gripper or arm), or it is sent to a non-reachable configuration. (3) software agent related failures, that may appear when e.g. the robot has software components that fail like when an algorithm is not able to extract the proper features. The paper describes the concepts and the implementation of failure interpretation ontology in several foundations like DUL and SUMO, and presents an example showing different situations in planning demonstrating the range of information the framework can provide for autonomous robotsPeer ReviewedPostprint (author's final draft

Development of a High Intensity Neutron Source at the European Spallation Source: The HighNESS project

The European Spallation Source (ESS), presently under construction in Lund, Sweden, is a multidisciplinary international laboratory that will operate the world's most powerful pulsed neutron source. Supported by a 3M Euro Research and Innovation Action within the EU Horizon 2020 program, a design study (HighNESS) is now underway to develop a second neutron source below the spallation target. Compared to the first source, located above the spallation target and designed for high cold and thermal brightness, the new source will provide higher intensity, and a shift to longer wavelengths in the spectral regions of cold (2 /- 20 {\AA}), very cold (VCN, 10 /- 120 {\AA}), and ultra cold (UCN, > 500 {\AA}) neutrons. The core of the second source will consist of a large liquid deuterium moderator to deliver a high flux of cold neutrons and to serve secondary VCN and UCN sources, for which different options are under study. The features of these new sources will boost several areas of condensed matter research and will provide unique opportunities in fundamental physics. Part of the HighNESS project is also dedicated to the development of future instruments that will make use of the new source and will complement the initial suite of instruments in construction at ESS. The HighNESS project started in October 2020. In this paper, the ongoing developments and the results obtained in the first year are described.Comment: 10 pages, 10 figures, 14th International Topical Meeting on Nuclear Applications of Accelerators, November 30 to December 4, 2021, Washington, D