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Differenzierungsklausel im allgemeinverbindlichen Tarifvertrag gemeinsamer Einrichtungen
Get PDFVor dem Hintergrund sinkender Tarifbindung und des politischen Ziels, die Tarifautonomie zu stärken, untersucht diese Dissertation eine bislang kaum beleuchtete Sonderkonstellation: Differenzierungsklauseln in allgemeinverbindlichen Tarifverträgen gemeinsamer Einrichtungen. Im Fokus stehen die rechtliche Einordnung und Bewertung solcher Klauseln vor dem Hintergrund der tarif- und verfassungsrechtlichen Rahmenbedingungen, insbesondere im Hinblick auf den Schutz der negativen Koalitionsfreiheit.
Zentraler Ausgangspunkt der Arbeit ist die systematische Trennung zwischen der tarifvertraglichen Regelungsebene und der Ebene der Allgemeinverbindlicherklärung. Während einfache Differenzierungsklauseln im Tarifvertrag als zulässig eingestuft werden, entfalten sie in Kombination mit der Allgemeinverbindlicherklärung und dem Institut der gemeinsamen Einrichtung eine weitergehende Wirkung: Durch die Einbindung in eine gemeinsame Einrichtung und die erstreckende Wirkung der Allgemeinverbindlicherklärung wird die Klausel zu einem effektiven Anreizmechanismus für eine Mitgliedschaft in Koalitionen, da sie Leistungen exklusiv für Tarifmitglieder sichert. Diese Wirkung wirft die Frage auf, ob und inwieweit ein solcher Eingriff im öffentlichen Interesse nach § 5 Abs. 1 TVG liegt.
In der Dissertation wird herausgestellt, dass es bei der Bewertung maßgeblich auf das öffentliche Interesse im Sinne von § 5 Abs. 1 TVG ankommt. Dieses ist durch eine Abwägung zwischen dem Interesse an der Erstreckung des Tarifvertrags und allen gegenläufigen Interessen zu ermitteln. Für die Gesamtabwägung wird der Grundsatz der Verhältnismäßigkeit zur Systematisierung herangezogen. Eine Differenzierung auf der Leistungsseite kann mit Blick auf die negative Koalitionsfreiheit der Außenseiter innerhalb des öffentlichen Interesses liegen. Bei einer Kombination aus Differenzierungsklausel auf der Leistungsseite und undifferenzierten Beitragspflichten der Außenseiter-Arbeitgeber muss dies jedoch anders bewertet werden. Eine solche Beitragspflicht belastet Außenseiter-Arbeitgeber nach Ansicht des Autors in verfassungsrechtlich unzulässiger Weise, da sie faktisch zur Mitfinanzierung exklusiver Leistungen gezwungen werden, ohne selbst Mitglied zu sein.
Die Arbeit gelangt zu dem Ergebnis, dass eine derartige Konstruktion nicht mehr allein dem Schutz des Tarifvertragssystems dient und als ungerechtfertigter Eingriff in die negative Koalitionsfreiheit der Außenseiter-Arbeitgeber zu werten ist. Durch die Kombination der Rechtsinstitute wird der Grundsatz der Koalitionsfreiheit (Art. 9 Abs. 3 GG) unterlaufen und das auf Mitgliedschaft beruhende Tarifvertragssystem ausgehebelt. Somit kann die untersuchte Sonderkonstellation nicht als verfassungskonforme Maßnahme zur Förderung der Tarifbindung gewertet werden
Essays on Labor Market Policy
Get PDFOptimal Short-Time Work Policy in Recessions:
Short-time work (STW) is a subsidy program linked to hours reduction that has been widely used around Europe to combat job losses in the Great Recession and the COVID-19 pandemic. Although typically used alongside an unemployment insurance (UI) system, the interaction between STW and UI remains conceptually unclear. To close this gap in the literature, I develop a search and matching model of the labor market with risk-averse workers, flexible hours choice, endogenous separations, and generalized Nash-Bargaining. Deriving closed-form expressions, I demonstrate that while the UI system provides income insurance to workers, the STW system mitigates the fiscal externality of UI-induced separations. Notably, STW only exists due to the UI system. Reflecting European practices, I allow the STW system to adjust over the business cycle while keeping the UI system constant. In line with the actual policy, my findings indicate that STW benefits have to increase in recessions, while in contrast to the actual use of STW, eligibility criteria have to be tightened. Interestingly, using UI with an optimal STW system is fiscally less expensive than the UI system on its own.
Optimal STW Policy and Labor Misallocation:
Short-time work (STW), a subsidy program linked to hours reduction, emerged as the central labor market instrument to combat unemployment in several European economies. As the scope of the instrument expanded, concerns arose about its impact on labor misallocation. To investigate this concern, I develop a search and matching model of the labor market, incorporating optimal STW policy. Information asymmetry hinders the government to discern between temporary unproductive firms, characterized by a high chance of recovery, and permanent unproductive firms, marked by a low chance of recovery. I show that the Ramsey planner wants to support temporary unproductive firms with high subsidies per period to prevent inefficient separations and permanent unproductive firms with low subsidies per period to foster the reallocation of workers. Optimal STW benefits need to trade-off the costs from excess worker retention in permanently unproductive firms against the costs of premature separations in temporary unproductive firms. Quantitative analysis shows that an optimally designed STW system can eliminate a substantial share of the costs associated with labor misallocation. If the government can observe firms’ separation intentions, it can improve outcomes by letting benefits decline over time to encourage reallocation from permanently unproductive firms. If not, a minimum hours reduction condition as eligibility criterium can serve as an effective screening tool for shock duration, rendering a declining schedule unnecessary.
Carrots or Sticks? Short-Time Work vs. Lay-off Taxes:
While unemployment insurance systems are widely used to insure workers against income losses after lay-offs, it is well known that they can inefficiently increase separations in the labor market. There are two common policy instruments that can counter this known problem: lay-off taxes and short-time work schemes. This study provides a search-and-matching framework to evaluate which of the two is the better policy tool. We show that if only a few firms are financially constrained, lay-off taxes are better because they do not distort working hours in the economy. With a large share of financially constrained firms, short-time work emerges as the superior tool, as lay-off taxes have trouble deterring separations in financially constrained firms. Additionally, short-time work can help provide insurance against income losses to risk-averse workers that constrained firms cannot afford to provide in their wage contracts. Calibrating the model to the U.S economy, we find that short-time work is the superior policy instrument if 40% of firms in the economy or more are financially constrained
Enhancing Data Interoperability in Alzheimer's Disease Cohort Studies via Comprehensive Semantic and Statistical Analyses
Get PDFAs a prominent neurodegenerative disorder, Alzheimer's disease causes extensive cognitive decline and remains a substantial public health concern. Despite extensive research to understand the pathology of the disease, no effective treatment has yet been discovered. This is potentially due to the heterogeneous nature of cohort studies used to assess Alzheimer’s disease and their respective biases. Additionally, Alzheimer’s research has been skewed toward a select few cohort studies that are not necessarily representative of the general population. This selection bias is likely driven by the open-access policies and availability of those cohort datasets. Finally, in general, cohort datasets are far from adhering to the Findable, Accessible, Interoperable, and Reusable data principles. This hinders cross-cohort investigations, leading to single-cohort analyses in the majority of research.
In this work, we evaluate several cohort studies that are either overanalyzed or underrepresented in Alzheimer’s disease research. Through meticulous comparison, we identify the semantic and statistical differences that exist across cohorts and highlight their data limitations and biases. To improve the structuring of datasets in line with the Findable, Accessible, Interoperable, and Reusable data principles, we generate an open-access web application aimed at improving cohort findability. We develop tools focused on the statistical comparison of cohort studies to assess their interoperability. Additionally, we provide researchers in this field with ample information regarding the data contained in the investigated cohorts, including modality, granular variable levels, and sources for acquiring the data (i.e., findability). We further harmonize the cohorts on a semantic level, leading to the creation of a common data model and the development of a data harmonization tool. Subsequently, the tool and the common data model are presented through another web application to accelerate the reusability of the data. Furthermore, we leverage our findings and efforts to assess cohort datasets on a deeper level. By performing two distinct evaluations, we highlight the variation in disease progression patterns across cohorts. These findings further reveal participant selection biases within the datasets and the immediate need to validate findings from single cohorts. Similarly, within our second analysis, we highlight that previous, data-driven thresholds applied for participant disease profiling (based on the absence or presence of pathology) are cohort-dependent and not interchangeable across cohorts. Therefore, participant categorization based on such thresholds varies substantially, indicating a lack of robustness
Ck7 und E-Cadherin in Plattenepithelkarzinomen des Kopf- und Hals-Bereiches
Get PDFPlattenepithelkarzinome des Kopf-Hals-Bereichs gehören weltweit zu den häufigsten malignen Tumoren dieser Region und sind durch hohe Rezidivraten und eine oft ungünstige Prognose gekennzeichnet. In dieser Arbeit wurde die Expression von Ck7 und E-Cadherin immunhistochemisch in TMAs untersucht, um mögliche Zusammenhänge mit tumorbiologischen Eigenschaften, Prognosefaktoren und Hinweisen auf eine epithelial-mesenchymale Transition (EMT) zu analysieren. Die Studie belegt CK7 als Prognosefaktor bei Plattenepithelkarzinomen des Kopf- und Hals- Bereiches. Eine CK7-Expression zeigt einen Zusammenhang mit niedriger Überlebensrate und mit einem positiven HPV-Status sowie eine Korrelation mit einer erhaltenen Expression von E-Cadherin und der Tumorgröße (T-Status).
Die Expression von E-Cadherin war in dieser Studie kein prognostischer Marker und zeigte keinen signifikanten Zusammenhang mit der Überlebensrate, der Tumorgröße, dem Nodalstatus oder mit dem HPV-Status. Zwar zeigt die Expression von CK7 in der hiesigen Studie eine Korrelation mit einem höheren Tumorstadium, doch da sich keine Korrelation mit dem Grading fand und überdies positiv mit dem klassischen anti-EMT- Marker E-Cadherin korreliert ist, gehen wir davon aus, dass die Expression von CK7 sich nicht als EMT-Marker in HNSCC eignet.
Für zukünftige Studien wird eine Analyse breiterer Tumorfläche mit Fokus auf Invasionsfront zu empfehlen. Die Untersuchung mit weiteren Markern, wie Vimentin und N-Cadherin, kann auch neue Erkenntnisse liefern
Development of photoreceptor-aptamer systems for the spatiotemporal control of gene expression
Get PDFGene expression regulation is a fundamental process underlying numerous biological mechanisms, from development and homeostasis to cellular responses and disease progression. Advances in the ability to control gene expression with high temporal and spatial precision have driven significant progress in synthetic and developmental biology. Although traditional methods using chemical or heat inducers have laid the groundwork for this field, they come with limitations that have prompted the need for development of tools which allow for control of gene expression with spatiotemporal precision. Optogenetics has emerged as a transformative approach, offering precise, non-invasive, and reversible control of gene activity using light-sensitive proteins.
This dissertation introduces the development of the flyPAL system, an optogenetic tool specifically designed for transcriptional activation in Drosophila melanogaster. The flyPAL platform integrates the spatial specificity provided by the GAL4-UAS system with the temporal control facilitated by the CRISPRa-PAL system. The core component of this system is the photoreceptor protein PAL (PAS-ANTAR-LOV), which undergoes reversible conformational changes in response to blue light and binds with high affinity to an RNA aptamer (53.19) in a light-dependent manner. By leveraging this interaction, flyPAL enables blue light-mediated, tissue-specific regulation of gene expression, allowing for precise spatial and temporal control. The efficacy of the flyPAL system was validated through experiments utilizing a fluorescent reporter gene (mRFP), demonstrating light-dependent and reversible gene expression in Drosophila Schneider 2 cells and in vivo in third-instar larvae. These findings establish flyPAL as an optoribogenetic tool for gene regulation studies, with potential to enhance investigations into dynamic biological processes and disease models.
Additionally, this research explores the use of another blue-light responsive photoreceptor protein, NdPAL1. NdPAL1 is a homolog of PAL and it undergoes reversible conformational changes in response to blue light, as PAL. NdPAL1 features a faster dark recovery rate compared to PAL, making it particularly well-suited for applications requiring rapid and reversible control, such as in neuroscience. An Opto- SELEX strategy was adapted to identify RNA aptamers that selectively bind to the light-activated state of NdPAL1, leading to the discovery of the TN10.2.21 aptamer. Functional studies demonstrated that NdPAL1 can perform light-switching in mammalian cells, highlighting its potential for real-time gene regulation in cellular environments.
Overall, this dissertation introduces flyPAL, an optoribogenetic tool for gene regulation in Drosophila, and demonstrates the development and optimization of RNA aptamers that bind to NdPAL1 in a light-dependent manner in vitro
Investigation of Photon Condensation in a Four-Site Lattice Unit Cell
Get PDFSince the first experimental realization of Bose-Einstein condensation in ultracold, dilute atomic gases in 1995, a broad research field exploring the physics of various intriguing quantum phenomena has developed. The Bose-Einstein condensate is a collective state occupied by many thousand atoms, forming a giant, coherent matter wave, which is formed due to quantum statistics and makes quantum effects observable at the macroscopic scale.
Apart from material particles, Bose-Einstein condensation can also be realized with gases of photons or photon-like quasiparticles in highly reflective microresonators. However, in contrast to atoms, where thermalisation is achieved by contact interactions, photonic condensates need to be coupled to a material component to exchange energy and thereby reach thermal equilibrium. The radiative coupling to a fluorescent dye solution inside the microcavity, where the broadband absorption and emission coefficients are connected by a Boltzmann-like frequency scaling, can provide such a thermalisation mechanism for photons.
The present thesis investigates Bose-Einstein condensation of photons into the ground state provided by a square lattice potential in the form of a unit cell with four sites, which is imprinted onto one of the cavity mirrors using a static structuring technique. The lattice structure is surrounded by a shallow harmonic potential, to provide a suitable density of states such that a Bose-Einstein condensate can exist. The eigenstates of the trapping potential are thoroughly characterized numerically as well as experimentally by selectively exciting the individual states and analysing the spectral photon distribution. Spatial and spectral photon distributions are recorded for different total photon numbers in the dye microcavity and good agreement with theoretical Bose-Einstein distributions at room temperature is found. It is verified that the condensate is indeed formed in the delocalized ground state of the lattice potential and the condensate is probed for phase coherence between lattice sites in a Mach-Zehnder type, multi-path interferometer. Remaining small deviations between the experiment and the theoretical expectations in terms of the precise photon distributions, photon numbers and finite saturation of the excited states are analysed and explained by taking into account the driven-dissipative nature of the microcavity environment. The experiments are performed in a regime where cavity loss and photon reabsorption occur on a comparable timescale. The rates of these competing processes can be experimentally tuned by varying the cavity cutoff. Close to equilibrium conditions can be obtained, when photon reabsorption is much faster than the loss of photons from the cavity, which corresponds to the regime of good thermalisation. In further work carried out in this thesis, the pump power required to reach the threshold for condensation or lasing-like behaviour is investigated theoretically and experimentally as a function of the cavity cutoff wavelength. It is found for the experimental parameters, that the cutoff wavelength at which the pump threshold reaches its minimum value is almost identical to the point, where the absorption rate of photons is the same as the cavity loss rate, i.e. at the crossover between condensation and lasing-like behaviour
Neuroprotective Role and Immunomodulatory Effects of Sialylation
Get PDFSialic acids are terminal sugars on the cellular glycocalyx, crucial for modulating immune responses in the sialylated central nervous system. Sialylation acts as an inhibitory checkpoint, regulating inflammation and tissue damage. Sialic acid-binding immunoglobulin-type lectins (SIGLECs), expressed on immune cells, bind sialylated glycoproteins and glycolipids, thereby inhibiting pro-inflammatory responses and phagocytosis. In the first part of this thesis the therapeutic effects of 6'-sialyllactose (6SL), a human milk oligosaccharide, in preventing neomycin-induced hearing loss in postnatal mice were explored. Systemic 6SL injection improved hearing, reduced macrophage activation in the cochlear spiral ganglion, and reversed the expression of the proinflammatory IL-1β and apoptotic Pik3cd gene transcripts. In vitro, 6SL demonstrated anti-inflammatory, anti-phagocytic, and neuroprotective effects on lipopolysaccharide-challenged THP1-macrophages, highlighting its therapeutic potential in inflammatory induced ototoxicity. In the second part the role of the human-specific SIGLEC-11 receptor in neurodegeneration and neuroinflammation in the aging brain was examined. Humanized Siglec-11 transgenic (tg) mice were studied at 6 and 24 months. Siglec-11 tg mice showed fewer Iba1-positive microglial cells, reduced lipid-laden microglia, and less neuronal loss compared to WT mice. Transcriptomic analysis revealed suppression of gene transcript pathways related to inflammatory and oxidative stress at 6 months, and complement and coagulation cascades at 24 months in Siglec-11 tg mice, suggesting a protective role for SIGLEC-11 in mitigating brain inflammation. In the third part the impact of age-related reduced sialylation on retinal inflammation and degeneration in Gne+/- mice with a heterozygous knock-out of the Gne gene was investigated. At 9 months, Gne+/- mice had lower polysialic and trisialic acid levels, higher CD68 expression, and at 12 months, fewer rod bipolar cells. Transcriptomic analysis revealed upregulated complement, inflammation, and apoptosis pathways, with increased pro-inflammatory and complement markers. Crossing Gne+/- mice with C3-deficient mice prevented CD68 elevation, rod bipolar cell loss, and increased C4 expression, indicating that retinal inflammation and cell loss in hyposialylation are driven by complement activation. These findings highlight the relevance of sialylation in modulating immunity and reducing inflammation, thus offering new options for treatment of neurodegenerative diseases
Amtliche Bekanntmachungen, 55. Jahrgang, Nr. 19
No full textÄnderung und zugleich Neubekanntmachung des Statuts des Transdisziplinären Forschungsbereichs/Transdisciplinary Research Area (TRA) TRA 2 – Bausteine der Materie und fundamentale Wechselwirkungen / Building Blocks of Matters and Fundamental Interactions der Rheinischen Friedrich-Wilhelms-Universität Bonn vom 7. April 202
Amtliche Bekanntmachungen, 55. Jahrgang, Nr. 33
No full textAkkreditierungsbeschluss vom 20. Mai 2025 - Geschichte (Bachelorteilstudiengang für Lehramt an Gymnasien und Gesamtschulen) - Geschichte (Masterteilstudiengang für Lehramt an Gymnasien und Gesamtschulen) - Philosophie/Praktische Philosophie (Bachelorteilstudiengang für Lehramt an Gymnasien und Gesamtschulen) - Philosophie/Praktische Philosophie (Masterteilstudiengang für Lehramt an Gymnasien und Gesamtschulen) - Praktische Philosophie (Bachelorteilstudiengang für Lehramt an Berufskollegs) - Praktische Philosophie (Masterteilstudiengang für Lehramt an Berufskollegs) - Wirtschaft-Politik/Sozialwissenschaften (Bachelorteilstudiengang für Lehramt an Gymnasien und Gesamtschulen) - Wirtschaft-Politik/Sozialwissenschaften (Masterteilstudiengang für Lehramt an Gymnasien und Gesamtschulen) - Wirtschaftslehre/Politik (Bachelorteilstudiengang für Lehramt an Berufskollegs) - Wirtschaftslehre/Politik (Masterteilstudiengang für Lehramt an Berufskollegs) vom 23. Mai 202
Amtliche Bekanntmachungen, 55. Jahrgang, Nr. 75
No full textBeschluss des Fakultätsrats der Mathematisch-Naturwissenschaftlichen Fakultät der Rheinischen Friedrich-Wilhelms-Universität Bonn zum Außerkraftsetzen der Prüfungsordnung für den Bachelorstudiengang „Molekulare Biomedizin“ vom 7. Oktober 202