Bayesian mapping of brain regions using compound Markov random field priors

Human brain mapping, i.e. the detection of functional regions and their connections, has experienced enormous progress through the use of functional magnetic resonance imaging (fMRI). The massive spatio-temporal data sets generated by this imaging technique impose challenging problems for statistical analysis. Many approaches focus on adequate modeling of the temporal component. Spatial aspects are often considered only in a separate postprocessing step, if at all, or modeling is based on Gaussian random fields. A weakness of Gaussian spatial smoothing is possible underestimation of activation peaks or blurring of sharp transitions between activated and non-activated regions. In this paper we suggest Bayesian spatio-temporal models, where spatial adaptivity is improved through inhomogeneous or compound Markov random field priors. Inference is based on an approximate MCMC technique. Performance of our approach is investigated through a simulation study, including a comparison to models based on Gaussian as well as more robust spatial priors in terms of pixelwise and global MSEs. Finally we demonstrate its use by an application to fMRI data from a visual stimulation experiment for assessing activation in visual cortical areas

Dynamic models in fMRI

Most statistical methods for assessing activated voxels in fMRI experiments are based on correlation or regression analysis. In this context the main assumptions are that the baseline can be described by a few known basis-functions or variables and that the effect of the stimulus, i.e. the activation, stays constant over time. As these assumptions are in many cases neither necessary nor correct, a new dynamic approach that does not depend on those suppositions will be presented. This allows for simultaneous nonparametric estimation of the baseline as well as the time-varying effect of stimulation. This method of estimating the stimulus related areas of the brain furthermore provides the possibility of an analysis of the temporal and spatial development of the activation within an fMRI-experiment

Finding Cepheid Variable Stars in Northern Dwarf Galaxies of the Local Group

Die vorliegende Arbeit “Suche nach Cepheid-artigen Veränderlichen Sternen in nördlichen Zwerggalaxien der Lokalen Gruppe” faßt die Ergebnisse des VarStarDwarves-Projektes für alle “blauen”, periodisch Variablen Sterne (VS) zusammen. Die Zielsetzung des VarStarDwarves-Projekts, das seit 1999 an der Universitäts-Sternwarte München betrieben wird, läßt sich am besten durch ein Zitat aus dem zugrundeliegenden DFG-Antrag (Ho1812) erläutern: “Die Bestimmung der Sternentstehungsgeschichte von Zwerggalaxien (ZG) erlaubt, wesentliche Randbedingungen für die Modelle der Evolution von Galaxien abzuleiten. Eine Grundvoraussetzung hierzu ist die Kenntnis der genauen Distanz der ZG. Die Beobachtung hinreichend großer Sample von Veränderlichen Sternen ermöglicht es, diese Distanzen wesentlich präziser als bisher zu bestimmen. Um diese großen Sample zu erhalten, sollen mit für Microlensing entwickelten Bildverarbeitungsmethoden VS in nahen ZG bis weit unter die bis jetzt erreichten Detektionsgrenzen nachgewiesen werden. Darüberhinaus werden die gefundenen VS auch Hinweise zur stellaren Zusammensetzung und damit zum Entwicklungszustand der ZG geben.” Die Ergebnisse für langperiodische, “rote” VS wurden bereits in der Arbeit von Snigula [2006] präsentiert. Im Rahmen des VarStarDwarves-Projekts wurden umfangreiche Modernisierungen und Verbesserungen an den Beobachtungsinstrumenten und dem Umfeld des Observatoriums Wendelstein durchgeführt und darüberhinaus die Entwicklung und der Bau einer neuen, modernen Zweikanal-CCD-Kamera initiiert. Auch diese Aspekte werden hier dokumentiert und die erreichten Fortschritte aufgezeigt (siehe hierzu Kapitel 2.2, 2.3 und 3 sowie die Anhänge A bis C). Diese Dissertation untergliedert sich weiter in eine Einleitung, die neben einer kurzen Vorstellung der mit dem Projekt befaßten Kollegen und ihrer diesbezüglichen Aufgabenbereichen v.a. eine historische Einführung in die Gebiete der Lokalen Zwerggalaxien sowie der “blauen” pulsationsveränderlichen Sterne bietet (Kap. 1), einen Überblick über Kandidatenauswahl und die durchgeführten Beobachtungen (Kap. 2.1, 2.4 und 2.5), sowie eine detaillierte Erläuterung der aufwendigen, z.T. ebenfalls im Rahmen des Projekts entwickelten Datenanalyseverfahren (Kap. 4). Die wesentlichen wissenschaftlichen Ergebnisse der Arbeit sind neue, unabhängige Entfernungsbestimmungen mittels δ Cephei Perioden-Leuchtkraftbeziehungen zu zwei der sechs VarStarDwarves Zwerge, die Bestätigung der Entfernung eines weiteren Zwergs, sowie die Entdeckung etlicher weiterer VS-Kandidaten, deren endgültige Bedeutungen erst durch weitere Beobachtungen bestimmt werden können, wobei aber durchaus mit weitreichenden Konsequenzen für das physikalische Verständnis der entsprechenden VS oder ihrer “Muttergalaxie” zu rechnen ist (Kap. 5)

Reconocimiento de una situación jurídica relativa al estatuto personal válidamente creada o modificada en el extranjero: Alemania

The case law of the CJEU and the ECtHR enhances the recognition of a status acquired abroad. The German legislative and judicative have consequently reacted, especially in the field of international name law. While the case law of the CJEU has fundamentally changed private international law approaches, the case law of the ECtHR so far has only been considered as a part of possible public policy arguments. Regarding the CJEU law, courts have developed a sophisticated system to “recognize” a status according to the theory of renvoi en bloc. This report describes how the aforementioned case law has changed and is changing the private international law methodology and practice.En algunas materias relacionadas con el estatuto de la persona, la jurisprudencia del TJUE y del TEDH ha fomentado el reconocimiento por parte de los Estados de las situaciones jurídicas válidamente creadas o modificadas en otros Estados. Esta jurisprudencia ha cambiado y está cambiando la metodología y práctica propias del Derecho internacional privado de producción interna. Este trabajo analiza los efectos de esta jurisprudencia europea sobre el Derecho internacional privado aleman cuando este se enfrenta a una situación jurídica relacionada con el estatuto de la persona que ha sido válidamente creada en el extranjero y que se quiere hacer valer en Alemania

Semiparametric Bayesian models for human brain mapping

Functional magnetic resonance imaging (fMRI) has led to enormous progress in human brain mapping. Adequate analysis of the massive spatiotemporal data sets generated by this imaging technique, combining parametric and non-parametric components, imposes challenging problems in statistical modelling. Complex hierarchical Bayesian models in combination with computer-intensive Markov chain Monte Carlo inference are promising tools.The purpose of this paper is twofold. First, it provides a review of general semiparametric Bayesian models for the analysis of fMRI data. Most approaches focus on important but separate temporal or spatial aspects of the overall problem, or they proceed by stepwise procedures. Therefore, as a second aim, we suggest a complete spatiotemporal model for analysing fMRI data within a unified semiparametric Bayesian framework. An application to data from a visual stimulation experiment illustrates our approach and demonstrates its computational feasibility

The recognition of a "judgment of paternity" in a case of cross-border surrogacy under German Law – commentary to BGH, 10 december 2014, az. Xii zb 463/13

The article comments on a recent decision of the BGH (German Supreme Court) regarding the recognition of a “judgment of paternity” which was obtained by a German couple in California after concluding an agreement with a surrogate mother in California. The German law is strictly opposed to any form of surrogacy; therefore earlier courts had usually denied recognition in similar cases for ordre public reasons. In this decision the BGH decided on the matter for the first time. Contrary to the lower instance courts she recognized the “judgment” after a careful weightening of all rights and policies involved. He came to the conclusion that the preponderant interests of the child outweighed all interest opposing a denial of recognition. The article describes the legal background of surrogacy and cross-border parenthood law. Afterwards, it explains the decision and which controversial issues the BGH decided. Finally it gives an outlook on those questions the BGH did not decide and how she probably will decide if she keeps her line of argument. Key Words: surrogacy, German private international law of parentage, recognition of foreign judgments under German law. Zusammenfassung: Dieser Artikel kommentiert die Entscheidung des BGH zur Anerkennung eines “judgment of paternity”, welches ein kalifornisches Gericht zugunsten eines deutschen Pärchens ausgesprochen hatte. Diese hatten vorher eine Leihmutterschaftsvereinbarung in Kalifornien nach kalifornischem Recht abgeschlossen. Das deutsche Recht lehnt alle Formen der Leihmutterschaft ab. Die unterinstanzlichen Gerichte versagten daher regelmäßig eine Anerkennung als ordre public-widrig. Der BGH entschied das erste Mal über die Frage. Er nahm eine Abwägung aller in Frage stehenden Rechte und Interessen vor und sprach sich – im Gegensatz zu den meisten unterinstanzlichen Gerichten – für eine Anerkennung aus. Ausschlaggegebend waren die Interessen des Kindes, die alle übrigen Interessen und Rechte überwogen. Der Beitrag gibt einen Überblick über die deutsche Rechtslage, erläutert dann die Entscheidung und gibt anschließend einen Ausblick bezogen auf die Fragen, welche der BGH offen ließ. Stichwörter: Leihmutterschaft, deutsches Abstammungskollisionsrecht, Anerkennung ausländischer Entscheidungen im deutschen Recht

Bayesian analysis of logistic regression with an unknown change point

We discuss Bayesian estimation of a logistic regression model with an unknown threshold limiting value (TLV). In these models it is assumed that there is no effect of a covariate on the response under a certain unknown TLV. The estimation of these models with a focus on the TLV in a Bayesian context by Markov chain Monte Carlo (MCMC) methods is considered. We extend the model by accounting for measurement error in the covariate. The Bayesian solution is compared with the likelihood solution proposed by Kuechenhoff and Carroll (1997) using a data set concerning the relationship between dust concentration in the working place and the occurrence of chronic bronchitis

Reconocimiento de una situación jurídica relativa al estatuto personal válidamente creada o modificada en el extranjero europea – un reto para la legislación nacional

In view of the ECJ and ECtHR case law on the recognition of names, same-sex marriages and parent-child relationships established abroad, this paper explores how various Member States conform with the resulting obligations. We compared 16 EU jurisdictions and their implementation of the aforementioned case law. Overall, a general tendency in favor of the recognition of a status acquired abroad can be observed; be it by the re-shaping of procedural recognition and private international law rules, or the application of new techniques, or an increasing restraint to reject recognition due to public policy reasons. Irrespective of the technique, however, a methodological struggle to comply with the European obligations is evident. Consequently, the mere registration of a status acquired abroad proves to be of increasing importance in practice.En algunas materias relacionadas con el estatuto de la persona, la jurisprudencia del TJUE y del TEDH ha fomentado el reconocimiento por parte de los Estados de las situaciones jurídicas válidamente creadas o modificadas en otros Estados. Esta jurisprudencia ha cambiado y está cambiando la metodología y práctica propias del Derecho internacional privado de producción interna. Comparamos 16 jurisdicciones de la UE y su aplicación de la jurisprudencia mencionada. En general, se observa una tendencia general a favor del reconocimiento de un estatuto adquirido en el extranjero; ya sea por la reconfiguración de las normas de reconocimiento procesal y de Derecho internacional privado, o por la aplicación de nuevas técnicas, o por una creciente moderación a la hora de rechazar el reconocimiento por razones de orden público. Sin embargo, independientemente de la técnica, es evidente la lucha metodológica para cumplir con las obligaciones europeas. En consecuencia, la mera registración de un estatus adquirido en el extranjero convierte más y más importante en la práctica

Práce s elektroodpadem při pracovní výchově

The thesis deals with the usability of electronic waste and other sorted waste in vocational education classes for primary school students. Regarding the usability of sorted waste, there is a lot of information available and schools have already learned to work with this material. However, it is different with electronic waste. The topic of electronic waste is not mentioned in the educational program for students. In the thesis, I compared the educational programs of four different primary schools to determine how this work could be incorporated into their plans. Some schools could easily include the work with electronic waste into their educational programs, while others may not introduce the topic until the second stage of elementary school education, for example, when students are introduced to working with wire. In the conclusion of the thesis, a research was conducted at a primary school in Karlovy Vary, where students were tasked with creating a product using sorted waste, including electronic waste. The attractiveness of using this material, the methods of connecting individual materials, and the final products were observed. In the end, interviews with the students about their products were conducted. This research showed that the usability of individual components of electronic waste in vocational education is very attractive for students. Additionally, with the increasing amount of electronic waste and its easy availability, it would be possible to include this topic in the educational program or curriculum for students

Assessing Brain Activity through Spatial Bayesian Variable Selection

Statistical parametric mapping (SPM), relying on the general linear model and classical hypothesis testing, is a benchmark tool for assessing human brain activity using data from fMRI experiments. Friston et al. (2002a) discuss some limitations of this frequentist approach and point out promising Bayesian perspectives. In particular, a Bayesian formulation allows explicit modeling and estimation of activation probabilities. In this paper, we directly address this issue and develop a new regression based approach using spatial Bayesian variable selection. Our method has several advantages. First, spatial correlation is directly modeled for activation probabilities and indirectly for activation amplitudes. As a consequence, there is no need for spatial adjustment in a post-processing step. Second, anatomical prior information, such as the distribution of grey matter or expert knowledge, can be included as part of the model. Third, the method has superior edge-preservation properties as well as being fast to compute. When applied to data from a simple visual experiment, the results demonstrate improved sensitivity for detecting activated cortical areas and for better preserving details of activated structures