Seawater effects on water flow and solute mobility in peat soils

This thesis aimed to reveal seawater effects on peat soil processes using different laboratory flow-through experiments. The results show that the effects depend on the environmental conditions, which are in turn affected by the peatland’s land-use history. The interaction of geochemical and hydrophysical soil properties determines the mobility of solutes. Initial leaching and desorption processes and, later on, an enhanced, sulfate-related decomposition of organic matter may lead to nutrient emission into adjacent aquatic ecosystems.Ziel dieser Doktorarbeit war es, Meerwassereffekte auf Torfbodenprozesse mithilfe verschiedener Säulenexperimente in Laborversuchen aufzuzeigen. Die Ergebnisse zeigen, dass die Effekte von den Umweltbedingungen abhängen, welche von der Landnutzung des Moores beeinflusst werden. Dabei bestimmt das Zusammenspiel von geochemischen und hydrophysikalischen Bodenparametern die Mobilität gelöster Stoffe. Anfängliche Auswaschungs- und Desorptionsprozesse und eine später einsetzende sulfatbasierte Zersetzung von org. Material können zu Nährstoffaustrag in angrenzende aquatische Ökosysteme führen

Understanding the Comorbidity of Asthma and Anxiety in Childhood: Characteristics, Vulnerabilities, and Treatment Implications

Introduction: Given the high incidence of asthma and anxiety comorbidity, clinicians should be informed of the unique presentation of these clients in clinical practice. Although much is known about the development and characteristics of childhood anxiety, less is known about children with anxiety and comorbid asthma. Methods: This study, using archival data, examined the potential differences in children with comorbid asthma and anxiety compared to children with anxiety from a random controlled trial. These two groups were compared on negative self-talk, number of physical symptoms, parent anxiety, content of their worries, and presence of panic, generalized anxiety, and separation anxiety disorder. Both groups were compared on their responsiveness to traditional Cognitive Behavioral Treatment for Childhood Anxiety. Discussion: Findings will contribute to more effective ways of addressing asthma in psychotherapy

Techniques for Payload Stabilization for Improved Photography During Stratospheric Balloon Flights

Payload-box rotation and swing are perennial challenges to achieving high-quality photography (typically videography) during weather-balloon flights to “near-space” (AKA the stratosphere). Continuous camera motion can lead to blurred still photos, nearly-impossible-to-watch video footage, and precludes time-exposure photography required for most astronomical imaging even though altitudes are reached where the daytime sky appears black. Apparently-random payload rotation, persisting even at altitude, can often exceed servo rotation rates and frustrate attempts to do active camera pointing. Here we discuss mostly-passive payload stabilization strategies we, and our collaborators, have used to mitigate and dampen both swing and rotation of suspended payloads on high-altitude balloon missions, primarily on ascent. In particular, we stress the importance of avoiding single “main” lines and of firmly coupling the payload stack to, as opposed to intentionally trying to decouple (rotationally) from, the neck of the balloon. We discuss consequences these strategies have on stack weight and also on the location of the parachute, sometimes displacing it from its normal location hanging between the neck of the balloon and the payload stack. We expect these payload stabilization techniques will be of particular interest to balloonists planning to photograph the total solar eclipse of August 2017

Basic Research of Material Properties of Mycelium-Based Composites

The subject of this research is growing mycelium-based composites and exploring their basic material properties. Since the building industry is responsible for a large amount of annual CO(2) emissions, rethinking building materials is an important task for future practices. Using such composites is a carbon-neutral strategy that offers alternatives to conventional building materials. Yet, in order to become competitive, their basic research is still needed. In order to create mycelium-based composites, it was necessary to establish a sterile work environment and develop shaping procedures for objects on a scale of architectural building elements. The composite material exhibited qualities that make it suitable for compression-only structures, temporary assemblies, and acoustic and thermal insulation. The methodology includes evaluating several substrates, focused on beech sawdust, with two mycelium strains (Pleurotus ostreatus and Ganoderma lucidum), density calculations, compression tests, three-point flexural tests and capillary water absorption. The results of this study are presented through graphical and numerical values comparing material and mechanical properties. This study established a database for succeeding investigations and for defining the potentials and limitations of this material. Furthermore, future applications and relevant examinations have been addressed

Contour Methods for View Point Tracking

Shape of objects, in particular the shape of object outlines, has for a long time been a focus in the literature and is widely regarded as carrying important information for visual and cognitive tasks, such as object recognition and object tracking. This thesis is concerned with techniques related to shape information from 2D images. The main contribution is a purely 2D shape based method for following view point changes of an observer relative to an object given an image sequence. Several techniques involved in such a task are covered in some detail. In particular, segmentation methods yielding contours, and shape representations are treated. On the shape side, classical representations and methods are included to a smaller extent, and a more recent, more sophisticated manifold of shapes including computational technicalities is treated in more detail. Variational segmentation methods based on the successful level set representation are used for segmenting and tracking curves in image sequences. While this field has grown rapidly and is still developing further, this work covers enough detail to describe the implementation used for experiments, as well as useful extensions to the basic methods. Finally, a method for tracking a view point relative to a moving object based only on 2D shape information is investigated and applied in experiments with some success. Future directions as well as limits of a purely outline based method are examined

Revisiting Robustness in Graph Machine Learning

Many works show that node-level predictions of Graph Neural Networks (GNNs) are unrobust to small, often termed adversarial, changes to the graph structure. However, because manual inspection of a graph is difficult, it is unclear if the studied perturbations always preserve a core assumption of adversarial examples: that of unchanged semantic content. To address this problem, we introduce a more principled notion of an adversarial graph, which is aware of semantic content change. Using Contextual Stochastic Block Models (CSBMs) and real-world graphs, our results uncover: $i)$ for a majority of nodes the prevalent perturbation models include a large fraction of perturbed graphs violating the unchanged semantics assumption; $ii)$ surprisingly, all assessed GNNs show over-robustness - that is robustness beyond the point of semantic change. We find this to be a complementary phenomenon to adversarial examples and show that including the label-structure of the training graph into the inference process of GNNs significantly reduces over-robustness, while having a positive effect on test accuracy and adversarial robustness. Theoretically, leveraging our new semantics-aware notion of robustness, we prove that there is no robustness-accuracy tradeoff for inductively classifying a newly added node.Comment: Published as a conference paper at ICLR 2023. Preliminary version accepted as an oral at the NeurIPS 2022 TSRML workshop and at the NeurIPS 2022 ML safety worksho

Social approach in preschool children with Williams syndrome: The role of the face.

Background Indiscriminate social approach behaviour is a salient aspect of the Williams syndrome (WS) behavioural phenotype. The present study examines approach behaviour in preschoolers with WS and evaluates the role of the face in WS social approach behaviour. Method Ten preschoolers with WS (aged 3-6 years) and two groups of typically developing children, matched to the WS group on chronological or mental age, participated in an observed play session. The play session incorporated social and non-social components including two components that assessed approach behaviour towards strangers, one in which the stranger’s face could be seen and one in which the stranger’s face was covered. Results In response to the non-social aspects of the play session, the WS group behaved similarly to both control groups. In contrast, the preschoolers with WS were significantly more willing than either control group to engage with a stranger, even when the stranger’s face could not be seen. Conclusion The findings challenge the hypothesis that an unusual attraction to the face directly motivates social approach behaviour in individuals with WS

Trauma as a predictor of exposure and response prevention (Ex/RP) treatment outcomes for patients with obsessive-compulsive disorder (OCD) in a clinical setting

Background: Trauma has been found to be highly prevalent among individuals diagnosed with obsessive-compulsive disorder (OCD) and to impact the onset, maintenance, and severity of OCD symptoms. Little is known, however, about how trauma might affect outcomes for individuals engaging in exposure and response prevention (Ex/RP). Despite Ex/RP being the most widely implemented treatment for OCD, lack of consideration for psychosocial factors, like experienced trauma, has been cited as a possible limitation of the treatment. Furthermore, intolerance of uncertainty (IU), anxiety sensitivity (AS), and emotion regulation (ER) are transdiagnostic variables most commonly associated with the presence of posttraumatic stress and OCD treatment success, respectively, however, no research to date has identified whether such variables might be implicated in the relationship between trauma and Ex/RP treatment outcomes. Objective: The primary aim of this study is to investigate how trauma might predict Ex/RP treatment outcomes for patients with OCD. The questions this study seeks to answer are: (1) Do OCD patients with trauma experience more severe OCD symptoms, IU, AS, and ER at pretreatment, compared to those without trauma? (2) Do the variables (i.e., IU, AS, and ER) mediate the relationship between trauma and Ex/RP treatment outcomes? Methods: Analyses of archival data will be performed on pretreatment and posttreatment measures of treatment-seeking patients with a primary OCD at a specialty anxiety clinic. Based on patient self-report on the Posttraumatic Diagnostic Scale for the DSM-5 (PDS-5; Foa, 2013) OCD patients will be separated into two groups: (1) those reporting no trauma experiences (OCD group), and (2) those reporting at least one trauma experience (OCDT group). A MANOVA will be used to assess whether the OCDT group report more severe OCD symptoms, IU, AS, and ER at pretreatment, compared to the OCD group. Second, based on those findings, a mediation analysis will be used to assess whether the variable found to differ most significantly between the groups (IU, AS, & ER) mediate the relationship between trauma and Ex/RP outcomes (severity change scores) at posttreatment. Discussion: Findings from this study have the potential to inform clinical practice around the assessment of OCD symptom presentation and the need to consider the impact of trauma and related transdiagnostic variables in the implementation of Ex/RP treatment to provide greater opportunity for successful treatment outcomes