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Evaluating the Digitalization in the Healthcare Sector: A User-Based Analysis
Get PDFThe German healthcare system faces enormous challenges, resulting from demographic changes with an increased number of people in need of care and a shortage of healthcare professionals. Additionally, the COVID-19 pandemic has intensified the burden on healthcare systems, accelerating digitalization efforts. Digitalization in healthcare can play a major role to overcome the described challenges and to improve the quality of healthcare services. In this dissertation, several user groups for digital applications are considered, ranging from patients to healthcare service providers. The research aims to identify challenges in healthcare digitalization and to elaborate on strategies to overcome these hurdles by analyzing emerging eHealth technologies and business models as well as various eHealth applications, such as pandemic dashboards, the electronic health record and case management software. With the analyses of eHealth artifacts, design recommendations for increasing user acceptance are generated. The design-oriented analyses consider the potential of AI, interactive elements and the wide range of potential user groups. Furthermore, with respect to the stakeholders involved, economic benefits and synergies of digitalization measures are identified. Recognizing healthcare’s societal and economic significance, the study underscores the potential for digitalization to improve efficiency and resource savings, while acknowledging existing hurdles
Sanktionen bei Verletzung vorvertraglicher Informationspflichten im spanischen Verbraucherrecht
No full textThema dieser Arbeit sind die Sanktionen bei Verletzung vorvertraglicher Informationspflichten im spanischen Verbraucherrecht am Beispiel des Fernabsatzvertrags. Während das Unionsrecht zwar die vorvertraglichen Informationspflichten für Fernabsatzverträge regelt, ist die Bestimmung der Rechtsfolgen bei etwaigen Verstößen gegen diese Informationspflichten weitestgehend den Mitgliedsstaaten überlassen. In der Arbeit wird untersucht, welche Maßnahmen und Rechtsfolgen der spanische Gesetzgeber zur Sanktionierung solcher Informationspflichtverletzungen vorgesehen hat. Untersuchungsgegenstand sind dabei die Regelungen des allgemeinen Verbraucherschutzgesetzes
Indolizidines from Actinomycetes: An Overview of Producers, Biosynthesis and Bioactivities
Get PDFIndolizidines have long been recognized for their valuable bioactivities, their common feature being a bicyclic structure connected via a nitrogen atom. Traditionally, plants have been identified as the primary producers. However, recent discoveries have revealed that certain bacterial strains belonging to the genus of actinomycetes also possess the ability to synthesize various indolizidine-based compounds. Among these strains, Streptomyces sp. HNA39, Saccharopolyspora sp. RL78, and Streptomyces NCIB 11649 have been identified as producers of cyclizidines, characterized by their distinctive cyclopropyl moiety. Additionally, Streptomyces griseus OS-3601 synthesizes a unique class of indolizidine derivatives known as iminimycins, distinguished by their rare imine-cation structure. Protoplast fusion of a Streptomyces griseus strain with Streptomyces tenjimariensis resulted in a new indolizidine named indolizomycin. This review aims to provide an overview of known bacterial indolizidine producers, summarize current knowledge regarding the biosynthesis of cyclizidines and iminimycins, and assess their respective bioactivities
Helping Blind People Grasp: Evaluating a Tactile Bracelet for Remotely Guiding Grasping Movements
Get PDFThe problem of supporting visually impaired and blind people in meaningful interactions with objects is often neglected. To address this issue, we adapted a tactile belt for enhanced spatial navigation into a bracelet worn on the wrist that allows visually impaired people to grasp target objects. Participants’ performance in locating and grasping target items when guided using the bracelet, which provides direction commands via vibrotactile signals, was compared to their performance when receiving auditory instructions. While participants were faster with the auditory commands, they also performed well with the bracelet, encouraging future development of this system and similar systems
Feeling good, approaching the positive
Get PDFIntroduction: Approach and avoidance behaviors have been extensively studied in cognitive science as a fundamental aspect of human motivation and decision-making. The Approach-Avoidance Bias (AAB) refers to the tendency to approach positive stimuli faster than negative stimuli and to avoid negative stimuli faster than positive ones. Affect and arousal in involved individuals are assumed to play a crucial role in the AAB but many questions in that regard remain open. With this in mind, the present study aimed to examine the impact of positive and negative mood on the AAB. Method: To achieve this goal, we conducted an experiment where participants watched either positive or negative videos prior to performing an approach-avoidance task. Results: We have not been able to confirm our preregistered hypothesis that mood induction moderates the AAB. Instead, our results suggest that an AAB can be robustly shown after both the positive and the negative intervention. Positive Affect Negative Affect Schedule (PANAS) results show that the participants' affective state was influenced by the mood intervention only in the form of increased emotional intensity. Participants did not self-report a change in mood valence that corresponds to the valence of the video primes. However, the behavioral data shows that after watching a positive video, participants are faster in approaching positive stimuli than negative stimuli. At the same time, we do not find a similar effect after the negative intervention. Discussion: These findings suggest that positive and negative affect might play an important role in shaping the AAB that is modulated by stimulus valence. This provides new potential insights into the underlying mechanisms of human motivation and decision-making. Specifically, we argue for potential differences between attention and reaction toward a valenced stimulus
Enhancing Safety in Autonomous Vehicles: The Impact of Auditory and Visual Warning Signals on Driver Behavior and Situational Awareness
Get PDFSemi-autonomous vehicles (AVs) enable drivers to engage in non-driving tasks but require them to be ready to take control during critical situations. This “out-of-the-loop” problem demands a quick transition to active information processing, raising safety concerns and anxiety. Multimodal signals in AVs aim to deliver take-over requests and facilitate driver–vehicle cooperation. However, the effectiveness of auditory, visual, or combined signals in improving situational awareness and reaction time for safe maneuvering remains unclear. This study investigates how signal modalities affect drivers’ behavior using virtual reality (VR). We measured drivers’ reaction times from signal onset to take-over response and gaze dwell time for situational awareness across twelve critical events. Furthermore, we assessed self-reported anxiety and trust levels using the Autonomous Vehicle Acceptance Model questionnaire. The results showed that visual signals significantly reduced reaction times, whereas auditory signals did not. Additionally, any warning signal, together with seeing driving hazards, increased successful maneuvering. The analysis of gaze dwell time on driving hazards revealed that audio and visual signals improved situational awareness. Lastly, warning signals reduced anxiety and increased trust. These results highlight the distinct effectiveness of signal modalities in improving driver reaction times, situational awareness, and perceived safety, mitigating the “out-of-the-loop” problem and fostering human–vehicle cooperation
Generic Micropatterned Pull-Down Assays for Quantifying Interaction Dynamics and Stoichiometry of Protein-Protein Interactions
No full textMany cellular functions are governed by an extensive network of protein-protein interactions (PPI) that exhibit regulatory mechanisms through core features such as affinity, avidity and competition. While fulfillment of essential functions such as cell growth, programmed cell death and immune response require a precisely tuned level of activity, dysregulation of such a tightly controlled network leads to serios consequences such as cancerous cell growth, pathogen susceptibility, or autoimmune diseases. Fundamental biological research at the protein level is therefore of vital interest, enabling breakthroughs in medicine while promoting the development of ever more advanced methods to help characterize the many unresolved PPIs.
One of the key factors of cellular signaling is the family of cytokines that regulate hematopoiesis and immunological homeostasis. Serving as the model system of this work, the type I interferon (IFN) signaling pathway plays a prominent role in the response against viral and intracellular bacterial infections. Type I IFN signaling employs a heterodimeric class II cytokine receptor (IFNAR1, IFNAR2), as well as cytosolic associated Janus family tyrosine kinases (JAK) and signal transducers and activators of transcription (STAT) as effector proteins. In general, the JAK-STAT pathway is the hallmark of the class I and II cytokine receptor families. Unique to type I IFN, however, are the negative feedback regulators USP18 and ISG15, which serve to regulate the long-term cellular response by desensitizing IFN signaling. While many insights have been gained in recent years at the receptor and JAK level, better mechanistic understanding of the interplay of cytosolic effector proteins and negative feedback regulators is required. This critically depends on quantifying dynamics and stoichiometry of their molecular interactions. On the one hand, bioanalytical characterization was traditionally tackled by biochemical methods and pull-down assays, but such in vitro techniques investigate PPIs far from their biological context and quantitative approaches are very demanding in terms of protein production and purification. In vivo techniques, on the other hand, are still challenging as it is not possible to change or control the protein concentrations in living cells. Moreover, many of these methods require target-specific optimization and leave much to be desired in terms of their reliability and simplicity of their overall strategy.
Overcoming these fundamental challenges, this thesis aimed to develop micropatterned nanobody-based pull-down assays to quantify the interaction dynamics and stoichiometry of cytosolic PPIs. These methods were used to characterize the PPIs of the type I IFN signaling pathway, but we also aspired to develop generically applicable strategies that can be used for a broad range of target proteins. Spatially-resolved nanobody immobilization was achieved by employing a robust poly-L-lysine grafted poly(ethylene glycol) (PLL-PEG) surface architecture, which can be readily generated via microcontact printing and provide surface passivation, biocompatibility and a functional micropatterning in a single step. The pull-down assays employ an anti-GFP nanobody directed against the widely used green fluorescent protein (GFP), providing a generalized targeting strategy instead of targeting a specific protein of interest. To this end, we have developed two methods: The first is nanobody live cell micropatterning, which enables spatiotemporal reorganization of cytosolic GFP-fused proteins inside cells to quantitatively investigate their interaction partners and dynamics. The second is in situ single cell pull-down (SiCPull), which directly captures GFP-fused proteins and interacting proteins from whole-cell lysates on the micropatterned chip, enabling background-free quantitative interaction dynamics analysis, and even stoichiometric analysis of individual protein complexes on the single molecule level (SM-SiCPull).
Using the nanobody live cell micropatterning, we could demonstrate that ISG15 acts as a double-edged sword. On the one side, ISG15 canonically rescues USP18 from proteolytic degradation, but on the other side interferes with USP18 binding to STAT2, thus partially obstructing USP18’s recruitment to IFNAR2 via STAT2. Furthermore, investigation on the protein domains revealed steric hindrance, as truncation of the N-terminal ISG15 domain abolished the competition. Moreover, SiCPull demonstrated a robust analysis of interaction dynamics of unstimulated STATs, ranging from stable interactions with a lifetime of half an hour, to transient interactions of only mere seconds. Using SM-SiCPull, we could analyze the stoichiometry of individual protein complexes, revealing that both unstimulated and IFN-induced phosphorylated STAT1 featured complex stoichiometries ranging from monomers and dimers to even tetramers.
The here presented methods have the potential for broad application in protein interaction analysis, as they are very robust and well compatible with modern cell biology, requiring only relatively simple equipment for microcontact printing, while employing nanobodies for a generalized pull-down strategy
Towards a Broader Understanding of Sustainable Consumption: Applying Psychological Insights for Evidence-Based Interventions
Get PDFTo solve the global crises related to climate change, joint global efforts of multiple stakeholders, including politics, the private sector, and individuals, are needed. On an individual level, current unsustainable consumption patterns have been linked to a myriad of environmental and social sustainability challenges, making the consumer a key actor in the sustainability transition. Thus, it is important to understand what drives individuals to act sustainably and how these drivers can be targeted to promote sustainable consumption. The present research aims to address this need by identifying key influences on sustainable consumption in different domains and proposes an evidence-based educational intervention to promote sustainable consumption. Three different papers, encompassing five studies using correlational survey, experimental and longitudinal methods, are included. First, psychological determinants from different research streams are integrated as predictors of sustainable consumption. Paper 1 finds knowledge-based, value-based, emotional and rational determinants to be generally predictive for sustainable consumption behavior of mobile phones, food, and fashion, with product-specific patterns emerging. Second, emotional processes are further examined as external antecedents of selected knowledge-based and rational determinants. Specifically, results of paper 2 highlight the importance of negative emotion-evoking photographic material in combination with a text appeal to raise problem awareness for the sustainability challenges of mobile phone consumption. Third, insights are applied in an educational intervention and evaluated in a field experiment in a school. Paper 3 indicates the long-term effectiveness of an experiential training intervention on knowledge-based, emotional, rational, and behavioral sustainable consumption outcomes. Overall, the appended studies contribute to identifying effective leverage points to promote sustainable consumption. This offers valuable scientific insights for designing evidence-based interventions, such as in education or marketing, and will be of significant interest to both researchers and policymakers
Entgrenzte Perspektiven? Eine komparatistische Analyse der Tier-Mensch-Relationen bei Thomas Mann, Juan Ramón Jiménez, Theodor Fontane und Miguel de Unamuno
No full textDie komparatistisch angelegte Arbeit untersucht auf Basis der zum Teil ökokritisch nuancierten 'Human-Animal Studies' unterschiedliche Tier-Mensch-Relationen und -Interaktionen in ausgewählten Werken von Thomas Mann, Juan Ramón Jiménez, Theodor Fontane und Miguel de Unamuno. Hierbei liegt der Fokus insbesondere auf möglichen graduellen Unterschieden und Gemeinsamkeiten nichtmenschlicher Tiere und Menschen innerhalb einer Tier-Mensch-Relation und -Interaktion sowie auf der Hinterfragung und Analyse der damit verbundenen 'Agency' – d.h. der Handlungsfähigkeit sowie -unfähigkeit beider Subjekte im Kontext ihres Aufeinandertreffens. So wird u.a. eruiert, inwieweit den werkimmanenten nichtmenschlichen Tieren eine gewisse kommunikative, agierende Subjektivität literarisch zu- oder abgesprochen wird – auch im Hinblick auf ihre möglichen mentalen Leistungen, Empfindungen oder Bedürfnisse. Des Weiteren schließt die Arbeit neben der individuellen Beleuchtung der interagierenden Protagonisten und einer humanimalischen, ökokritischen Analyse der dort literarisch dargebotenen Umwelt bzw. Natur zudem Untersuchungen und Reflexionen über den im jeweiligen Werk inhärenten Sprachduktus mit ein. Die Aufnahme vielschichtiger Analyseaspekte ermöglicht so eine detaillierte Visualisierung von Tier-Mensch-Tableaus, durch die neue, alternative Perspektiven entstehen sowie Schlussfolgerungen und Resultate angesichts des im Werk jeweilig (re)präsentierten Tier-Mensch-Verhältnisses exemplifiziert werden können
Approximation Algorithms for Multistage Subgraph Problems
No full textThe concepts of classical graph theory offer a framework for modeling problems from almost all areas of life. Temporal graphs in particular provide a way to represent and analyze dynamic data, enabling algorithmic solutions to problems dealing with structures that change over time. For the extension to time-related data, different modifications of the graph concept can be useful, depending on the optimization goal. In this work, the focus is on the analysis of problems on finite sequences of graphs whose sequence members are to be read as snapshots of the same graph at different points in time.
The key topic is to solve a given combinatorial optimization problem on a sequence of graphs such that the resulting solution sequence satisfies two conditions: (i) each solution is optimal for its respective graph and (ii) solutions of successive graphs are as similar as possible. Problems of this abstract form are called multistage problems, since their instances consist of multiple stages.
First, the classical assignment problem Maximum Matching is exemplarily transferred into such a multistage setting. For the two resulting problems MIM and MUM, various approximation algorithms and reductions are developed. The algorithmic approaches for MIM can be generalized to apply to a broad class of multistage formulations of classical problems in graph theory. This general class of problems on multistage graphs, the so-called Multistage Subgraph Problems, is the focus of the second part of this thesis. After discussing the corresponding definitions and adapted algorithms, we present numerous examples of MSPs, where these adapted algorithms can be applied. As we also study the complexity of each example, this provides an overview of the similarities and differences of such multistage problems. In a third part, the performance of the approximation algorithms in practice is investigated by applying them to example instances for the Multistage Shortest Path problem. A comparison is made with derived heuristics and an exact (but slow) algorithm, investigating their respective solution quality and running time. Additional problem-specific results on Multistage Shortest Path and Multistage Minimum Weight Spanning Tree complete the thesis