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Evaluation of an eye tracking setup for studying visual attention in face-to-face conversations
(2021)
Many eye tracking studies use facial stimuli presented on a display to investigate attentional processing of social stimuli. To introduce a more realistic approach that allows interaction between two real people, we evaluated a new eye tracking setup in three independent studies in terms of data quality, short-term reliability and feasibility. Study 1 measured the robustness, precision and accuracy for calibration stimuli compared to a classical display-based setup. Study 2 used the identical measures with an independent study sample to compare the data quality for a photograph of a face (2D) and the face of the real person (3D). Study 3 evaluated data quality over the course of a real face-to-face conversation and examined the gaze behavior on the facial features of the conversation partner. Study 1 provides evidence that quality indices for the scene-based setup were comparable to those of a classical display-based setup. Average accuracy was better than 0.4° visual angle. Study 2 demonstrates that eye tracking quality is sufficient for 3D stimuli and robust against short interruptions without re-calibration. Study 3 confirms the long-term stability of tracking accuracy during a face-to-face interaction and demonstrates typical gaze patterns for facial features. Thus, the eye tracking setup presented here seems feasible for studying gaze behavior in dyadic face-to-face interactions. Eye tracking data obtained with this setup achieves an accuracy that is sufficient for investigating behavior such as eye contact in social interactions in a range of populations including clinical conditions, such as autism spectrum and social phobia.
Advances in eye tracking technology have enabled the development of interactive experimental setups to study social attention. Since these setups differ substantially from the eye tracker manufacturer’s test conditions, validation is essential with regard to the quality of gaze data and other factors potentially threatening the validity of this signal. In this study, we evaluated the impact of accuracy and areas of interest (AOIs) size on the classification of simulated gaze (fixation) data. We defined AOIs of different sizes using the Limited-Radius Voronoi-Tessellation (LRVT) method, and simulated gaze data for facial target points with varying accuracy. As hypothesized, we found that accuracy and AOI size had strong effects on gaze classification. In addition, these effects were not independent and differed in falsely classified gaze inside AOIs (Type I errors; false alarms) and falsely classified gaze outside the predefined AOIs (Type II errors; misses). Our results indicate that smaller AOIs generally minimize false classifications as long as accuracy is good enough. For studies with lower accuracy, Type II errors can still be compensated to some extent by using larger AOIs, but at the cost of more probable Type I errors. Proper estimation of accuracy is therefore essential for making informed decisions regarding the size of AOIs in eye tracking research.
Fälle von Kindesmisshandlung schrecken immer wieder die Öffentlichkeit wach und haben den Ruf nach einem früheren Tätigwerden des Staates immer lauter werden lassen. Der Beitrag geht der Frage nach, ab wann und mit welchen Mitteln sich der Staat im Interesse des Kindesschutzes in die Familie hineinbewegen kann und darf. Damit soll ein kleiner Beitrag zur Schnittstelle zwischen Elternprimat und staatlicher Verantwortung für den Kindesschutz auf den zwei Ebenen Kinder- und Jugendhilfe einerseits sowie Familiengericht andererseits geleistet werden.
Phylogeographic analyses point to long-term survival on the spot in micro-endemic Lycian salamanders
(2020)
Lycian salamanders (genus Lyciasalamandra) constitute an exceptional case of microendemism of an amphibian species on the Asian Minor mainland. These viviparous salamanders are confined to karstic limestone formations along the southern Anatolian coast and some islands. We here study the genetic differentiation within and among 118 populations of all seven Lyciasalamandra species across the entire genus’ distribution. Based on circa 900 base pairs of fragments of the mitochondrial 16SrDNA and ATPase genes, we analysed the spatial haplotype distribution as well as the genetic structure and demographic history of populations. We used 253 geo-referenced populations and CHELSA climate data to infer species distribution models which we projected on climatic conditions of the Last Glacial Maximum (LGM). Within all but one species, distinct phyloclades were identified, which only in parts matched current taxonomy. Most haplotypes (78%) were private to single populations. Sometimes population genetic parameters showed contradicting results, although in several cases they indicated recent population expansion of phyloclades. Climatic suitability of localities currently inhabited by salamanders was significantly lower during the LGM compared to recent climate. All data indicated a strong degree of isolation among Lyciasalamandra populations, even within phyloclades. Given the sometimes high degree of haplotype differentiation between adjacent populations, they must have survived periods of deteriorated climates during the Quaternary on the spot. However, the alternative explanation of male biased dispersal combined with a pronounced female philopatry can only be excluded if independent nuclear data confirm this result.
The changing views on the evolutionary relationships of extant Salamandridae (Amphibia: Urodela)
(2018)
The phylogenetic relationships among members of the family Salamandridae have been repeatedly investigated over the last 90 years, with changing character and taxon sampling. We review the changing composition and the phylogenetic position of salamandrid genera and species groups and add a new phylogeny based exclusively on sequences of nuclear genes. Salamandrina often changed its position depending on the characters used. It was included several times in a clade together with the primitive newts (Echinotriton, Pleurodeles, Tylototriton) due to their seemingly ancestral morphology. The latter were often inferred as a monophyletic clade. Respective monophyly was almost consistently established in all molecular studies for true salamanders (Chioglossa, Lyciasalamandra, Mertensiella, Salamandra), modern Asian newts (Cynops, Laotriton, Pachytriton, Paramesotriton) and modern New World newts (Notophthalmus, Taricha). Reciprocal non-monophyly has been established through molecular studies for the European mountain newts (Calotriton, Euproctus) and the modern European newts (Ichthyosaura, Lissotriton, Neurergus, Ommatotriton, Triturus) since Calotriton was identified as the sister lineage of Triturus. In pre-molecular studies, their respective monophyly had almost always been assumed, mainly because a complex courtship behaviour shared by their respective members. Our nuclear tree is nearly identical to a mito-genomic tree, with all but one node being highly supported. The major difference concerns the position of Calotriton, which is no longer nested within the modern European newts. This has implications for the evolution of courtship behaviour of European newts. Within modern European newts, Ichthyosaura and Lissotriton changed their position compared to the mito-genomic tree. Previous molecular trees based on seemingly large nuclear data sets, but analysed together with mitochondrial data, did not reveal monophyly of modern European newts since taxon sampling and nuclear gene coverage was too poor to obtain conclusive results. We therefore conclude that mitochondrial and nuclear data should be analysed on their own.
Die Anpassung der Systeme der sozialen Sicherung an die gewandelten wirtschaftlichen, demographischen und sozialen Verhältnisse stellt für die europäische Sozialpolitik im allgemeinen und für die Alterssicherung im besonderen eine große Herausforderung dar. In den mittel- und osteuropäischen Staaten wurde der mühsame Prozeß der Anpassung der sozialen Sicherungssysteme an die veränderten Rahmenbedingungen zusätzlich erschwert durch die Notwendigkeit, wirtschaftliche Stärke und demokratische Institutionen gleichzeitig zu entwickeln. Die Möglichkeit, von anderen Ländern zu lernen, ist deshalb für die mittel- und osteuropäischen Staaten besonders wichtig. Dabei schließt der Prozeß des Lernens neben dem Aussuchen und Auswerten von Informationen auch Verhaltensänderungen ein, die für die erfolgreiche Durchführung von Reformen in diesen Ländern nützlich sein können. In der vorliegenden Studie wird untersucht, ob bei den Reformen im Bereich der Alterssicherung im Verhältnis von osteuropäischen und westeuropäischen Ländern ein Lernprozeß in Gang gesetzt worden ist und ob ein Austausch von Bearbeitungsansätzen stattgefunden hat. Dabei ist in keinem der untersuchten Länder - Deutschland, Großbritannien, Polen und Bulgarien " ein tatsächliches oder auch nur vorläufiges Ende des Reformprozesses festzustellen. In der Studie werden auch die kulturellen und sozialen Voraussetzungen für die Akzeptanz neuer Systeme der Alterssicherung in den mittel- und osteuropäischen Staaten untersucht, da der Erfolg der Reformen im Bereich der Alterssicherung von den langsamen und nur schwer steuerbaren Veränderungen der politischen Kultur und der Mentalität abhängig ist.
In this thesis, in order to shed light on the biological function of the membrane-bound Glucocorticoid Receptor (mGR), proteomic changes induced by 15 min in vivo acute stress and by short in vitro activation of the mGR were analyzed in T-lymphocytes. The numerous overlaps between the two datasets suggest that the mGR mediates physiologically relevant actions and participates in the early stress response, triggering rapid early priming events that pave the way for the slower genomic GC activities. In addition, a new commercially available method with suitable sensitivity to detect the human mGR is reported and the transcriptional origin of this protein investigated. Our results indicates that specific GR-transcripts, containing exon 1C and 1D, are associated with the expression of this membrane isoform.
Die Notwendigkeit einer rechtlichen Regelung der Sterbehilfe ist seit langem Gegenstand intensiver Diskussion in Deutschland, die Rechtsunsicherheit bezüglich zulässiger bzw. unzulässiger Sterbehilfe heute aber größer denn je. Der erste Beitrag setzt sich mit den Gründen dieser Entwicklung auseinander und zeigt Möglichkeiten auf, wie der Bereich zulässiger Sterbehilfe im Strafrecht ohne Verlust an Einzelfallgerechtigkeit präzisiert werden kann. Der sich anschließende Beitrag geht auf die luxemburgische Gesetzgebung zur Sterbehilfe ein. Schließlich werden die Beiträge aus der Sicht eines Palliativmediziners unter Heranziehung von Fällen aus der Praxis diskutiert.
This work studies typical mathematical challenges occurring in the modeling and simulation of manufacturing processes of paper or industrial textiles. In particular, we consider three topics: approximate models for the motion of small inertial particles in an incompressible Newtonian fluid, effective macroscopic approximations for a dilute particle suspension contained in a bounded domain accounting for a non-uniform particle distribution and particle inertia, and possibilities for a reduction of computational cost in the simulations of slender elastic fibers moving in a turbulent fluid flow.
We consider the full particle-fluid interface problem given in terms of the Navier-Stokes equations coupled to momentum equations of a small rigid body. By choosing an appropriate asymptotic scaling for the particle-fluid density ratio and using an asymptotic expansion for the solution components, we derive approximations of the original interface problem. The approximate systems differ according to the chosen scaling of the density ratio in their physical behavior allowing the characterization of different inertial regimes.
We extend the asymptotic approach to the case of many particles suspended in a Newtonian fluid. Under specific assumptions for the combination of particle size and particle number, we derive asymptotic approximations of this system. The approximate systems describe the particle motion which allows to use a mean field approach in order to formulate the continuity equation for the particle probability density function. The coupling of the latter with the approximation for the fluid momentum equation then reveals a macroscopic suspension description which accounts for non-uniform particle distributions in space and for small particle inertia.
A slender fiber in a turbulent air flow can be modeled as a stochastic inextensible one-dimensionally parametrized Kirchhoff beam, i.e., by a stochastic partial differential algebraic equation. Its simulations involve the solution of large non-linear systems of equations by Newton's method. In order to decrease the computational time, we explore different methods for the estimation of the solution. Additionally, we apply smoothing techniques to the Wiener Process in order to regularize the stochastic force driving the fiber, exploring their respective impact on the solution and performance. We also explore the applicability of the Wiener chaos expansion as a solution technique for the simulation of the fiber dynamics.
Although geographically it belongs to Europe, as far as the constitutionality control of the statutory provisions is concerned, Greece follows the American system. That means that there is no Constitutional Court and, on the contrary, every court (even those of first instance) are entitled, and indeed obliged, to control the constitutionality of the laws (Articles 87 par. 2 and 93 par. 4 of the Greek Constitution). The Greek Courts examine only the substantial and not the formal constitutionality of the statutory provisions. If a court comes to the result of the unconstitutionality, then the statutory provision is not annulled and removed from the legal order, but it is not applied by the court in the relevant court procedure. The only – rather rare – case where a statutory provision is erga omnes annulled is when this is ordered by a decision of the Highest Special Court (Article 100 of the Greek Constitution), following a disagreement between two of the three highest Courts, namely between Symvoulio tis Epikrateias (highest Administrative Court), Areios Pagos (Cassations Court in Civil and Criminal procedures) and Elegtiko Synedrio (Court of Audit).
The presentation is going to examine the origins of the Greek system of the constitutionality control. It will also focus on the advantages and disadvantages of the Greek system and on the scientific and political discussion. Last but not least, the presentation will examine the role of the Council of State, which, although formally not a Constitutional Court, in practice issues the vast majority of the court decisions which accept the unconstitutionality of statutory provisions.