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Fiscal Sustainability of Health Systems in sub-Saharan Africa: An Analytical Framework and Evidence from Zambia
Full text linkOver the past three decades, several countries worldwide have experienced a rapid and unsustainable increase in total health expenditures. In contrast, health financing in Africa has been diminishing due to reduced domestic revenue mobilisation, high public debt, and declining external financing. Persistent infectious disease outbreaks and natural disasters have also overwhelmed the already weak health systems in Africa. Increasing health care needs coupled with decreasing spending on health make it difficult to provide quality health care in low- and lower middle-income countries (LLMICs) in Africa. Despite the growing challenge of fiscal sustainability of health systems in LLMICs in Africa, there is no comprehensive study on the subject-matter. Motivated by knowledge and methodological gaps in the existing literature, this study assessed the main drivers of changes in total and public expenditure on health in Zambia by looking at macro-fiscal factors, funding sources, demographic, health, institutional, and social factors at national and sub-national levels. The study has addressed the following research question: To what extent is the Zambian health system financially sustainable?
Given that Zambia's macro-fiscal, demographic, epidemiological, and health system profile are comparable to those in other LLMICs in Africa, the study was conducted in Zambia. To meet the first objective of the study, panel regression analysis and the Das Gupta decomposition method were used to assess the main determinants of total and public expenditures on health in Zambia at national level; and government health spending at sub-national level. Decomposition analysis made it possible to disintegrate and quantify changes in health expenditures by key factors. For the second objective of the study, an extensive literature review was undertaken to conceptualise and adapt an analytical framework for fiscal sustainability of health systems in LLMICs. To achieve this, reference was made to existing supply- and demand-side theories on the determinants of health expenditures; the general body of work on fiscal policy sustainability; and health-sector specific studies on fiscal sustainability and health system resilience. Thereafter, a predictive analysis of future financing needs and fiscal space for health was undertaken to gauge if the health system in Zambia was financially sustainable.
The results show a substantial reduction in funding to the health sector in Zambia over the period 2013-2019, particularly for government domestic spending on health. This suggests a de-prioritisation of health spending by the Zambian government. Furthermore, the results show that expenditure per prevalent case was the main cause of the reduction in total health expenditures in Zambia. There was decreased spending on HIV/AIDS and sexually transmitted infections, followed by non-communicable diseases, and malaria and neglected tropical diseases. The reductions were predominant in the 15-49 age group.
At the provincial level, there was low budget performance and a persistent decline in per capita government health expenditure. The main driver of the reduction in per capita government health spending was the number of TB notifications per 10,000 people, followed by GDP per capita. On the other hand, the number of health facilities per 10,000 people and the level of urbanization mitigated the overall reduction in per capita government health spending. However, each of these factors had distinct impacts on changes in the per capita government health expenditure across the provinces. The study predicts a total ‘effective’ health financing gap of US92 per capita over the period 2025-2030. This gap can be attributed to projected reductions in per capita spending on health by the government and external development partners.
The study concludes that Zambia’s health system is financially unsustainable, with government health financing deprioritized from 2013-2019, and a significant financing gap projected for 2025-2030. The main determinants of total health spending are HIV/AIDS and sexually transmitted infections in the 15-49 age group. At the provincial level, key factors influencing per capita government health spending are TB notifications, GDP per capita, the number of health facilities, and the level of urbanization. To sustain the functionality of the health system in Zambia, the study advocates for sufficient government health funding, increased predictability of funding, and improved efficiency in resource allocation and use. The study also calls for regular monitoring and matching of available funds with the health care needs of the population. Future research could assess the effectiveness of health spending, determinants of health spending at the district level, sustainability of system-level interventions (i.e. the National Health Insurance Scheme), and rising number of specialized hospitals
Introducing Project-W: A self-hostable platform for OpenAI’s Whisper
Full text linkSpeech-to-text technologies, driven by advancements in artificial intelligence, are increasingly beneficial to sectors like research and education. These systems enable the transcription of vast audio data, making it easier to process, analyze, and archive information. However, concerns over data privacy and reliance on cloud-based services have prompted the need for self-hosted solutions. Project-W addresses these issues by providing a private, AI-driven transcription platform based on OpenAI's Whisper general-purpose speech recognition model.
The main goal of Project-W is to offer an easy open-source, scalable transcription solution that ensures data privacy by running entirely on local infrastructure. Specifically, it is designed for environments like universities and research institutions that handle sensitive information. By eliminating the need for cloud services, Project-W safeguards data while leveraging powerful AI models for accurate transcription. It aims to simplify transcription workflows, enabling users to manage their audio processing needs efficiently and securely.
Project-W is built with a Flask-based backend, a Svelte-powered frontend, and Python runners. The backend handles transcription tasks, while the frontend provides an intuitive interface for users to submit, track, and retrieve jobs. Python runners manage the interaction with OpenAI's Whisper AI model, and all components communicate via an HTTP REST API. The platform supports deployment on high-performance hardware, optimizing the processing of large and complex models. Key features include local data storage, user-friendly job management, and scalable infrastructure to handle varying workloads, making it adaptable to diverse environments.
Preliminary testing of Project-W in a university setting demonstrates that the platform is capable of handling significant transcription workloads while maintaining high levels of data security. Its modular architecture allows for customization based on user requirements, such as integrating with institutional servers or enhancing hardware capabilities to improve transcription speed. The platform’s user-friendly web interface streamlines job management, ensuring that even non-technical users can effectively utilize the tool.
Ongoing work focuses on optimizing the platform's performance for large-scale use while actively gathering feedback from both users and administrators to improve functionality and user experience. Further evaluations will be conducted to assess its viability as a central transcription service across other departments, with a view toward broad institutional adoption
The role of ERRFI1 in melanoma progression and resistance towards targeted therapy
Full text linkMelanoma is the most lethal type of skin cancer that originates from melanocytes. Targeted therapy, as one of the main therapeutic methods for melanoma, achieves great
clinical efficiency at the beginning of treatment. However, drug resistance inevitably
arises due to mechanisms such as the reactivation of the MAPK pathway. Our lab
previously demonstrated that ERBB receptor feedback inhibitor 1 (ERRFI1), a neural
crest-associated gene, is highly expressed in metastatic melanoma and correlates with
poor prognosis. In this study, I validated that ERRFI1 expression was upregulated in
melanoma and demonstrated that it positively correlated with AXL expression, but negatively correlated with SOX10 and MITF expression, as well as with melanocytic differentiation markers, including TYR, DCT, and MLANA. Downregulation of ERRFI1 increased the sensitivity of melanoma cells to vemurafenib (BRAF inhibitor). Furthermore, high ERRFI1 expression levels were found in BRAF inhibitor (BRAFi)-resistant
cells. Loss of ERRFI1 resensitized BRAFi-resistant melanoma cells to vemurafenib.
Mass spectrometry-based proteomic analysis between ERRFI1 knockdown (KD) and
control samples revealed that silencing ERRFI1 inhibited the reactivation of ERK and
AKT signaling pathways, which usually contribute to promoting drug resistance. Furthermore, miR-200c was identified as a tumor-suppressive microRNA that targeted the
3' UTR of ERRFI1, resulting in its downregulation. This also resensitized BRAFi-resistant melanoma cells to vemurafenib. This study highlights the critical role of ERRFI1
in melanoma progression. These findings suggest that ERRFI1 is a promising therapeutic target for treating melanoma and offers potential strategies for overcoming drug
resistance
A novel pulse-chase fluorescence imaging approach for the analysis of HIV-1 cell-to-cell transmission and spread
Full text linkTransmission of HIV-1 after particle assembly and budding from the membrane of infected T cells can occur by two different modes: cell-free infection, where particles are released into the extracellular space and traffic to susceptible cells by diffusion, and cell-associated transmission by direct cell-cell contacts via so-called virological synapses (VS). In this dissertation, I established a novel approach to visualize HIV-1 cell-to-cell transmission using pulse-chase labeling to separately identify viral transfer and productive infection. To this end, I successfully established and characterized a fully replication-competent labeled HIV-1 derivative, HIV-1iSNAPf(opt). I could demonstrate that this derivative exhibited near wild-type levels of infectivity and remarkably stable integration of SNAPf into the group-specific antigen (Gag), as evidenced by the detection of SNAPf-tag expression by flow cytometry and Western blot after prolonged passaging in A3.01 T cells. In addition, the effect of codon optimization within sfGFP and SNAPf upon insertion into Gag was investigated, based on the previous observation that an increased level of CpG dinucleotides leads to RNA degradation by the Zinc-finger Antiviral Protein (ZAP). No notable enhancement in replication kinetics or infectivity was observed for the codon-optimized derivatives, when a time course was conducted in infected A3.01 T cells and infectivity assays were performed in reporter cell lines.
Furthermore, I developed a real-time method for the detection of productive cell-to-cell transmission. This was accomplished by labeling Gag.SNAPf in the donor cell population with a cell-permeable benzylguanine (BG)-conjugated SNAP dye, followed by continuous observation of Gag.SNAPf expression in contacted target cells, in presence of a novel, highly fluorogenic dye “SNAP23”. Moreover, a semi-automated analytical pipeline, developed in collaboration with ZEISS Arivis, was utilized to quantitatively analyze the factors influencing the dynamics of VS formation and to establish a correlation between cell-to-cell transfer and Gag.SNAPf expression in contacted target cells. The results of the quantitative analyses indicated that a single contact was sufficient to induce new Gag expression in the target cell, regardless of the duration of the contact. Furthermore, new Gag.SNAPf expression was observed in target cells as early as 30 minutes after VS formation, indicating the potential for direct translation of incoming genomic RNA. In conclusion, pulse-chase labeling of HIV-1 infection and cell-to-cell transmission offers a versatile tool for studying the various stages of the HIV-1 replication cycle. In the context of VS, this is the first instance in which distinct contact events have been directly correlated with novel Gag.SNAPf(opt) expression in target cells
Asteroseismic Structure Inversions of Solar-like Oscillators
Full text linkThe study of stars through their global oscillations, i.e., asteroseismology, has provided unprecedented insight into stellar interiors. One of the most powerful techniques of asteroseismology is that of structure inversions. This technique can localize and quantify differences in sound speed between a star and its best-fit model. These differences, then, are a direct test of the accuracy of our stellar models.
The first part of this thesis outlines the specifics of the inversion procedure and then applies it to 55 main-sequence stars observed by the Kepler mission with masses between 1 and 1.6 solar masses. This discussion is split into stars with radiative and convective cores. Overall, the inversions reveal that our best-fit models match the sound speed profile in around half of the stars studied. In the remaining half of the sample, there is an even split between cases where the model sound speed is too high and cases where it is too low.
The second part of this thesis explores whether current inversion techniques are suitable for subgiant stars. These stars exhibit mixed modes that are sensitive to deeper regions of stellar cores. As the sensitivity of these mixed modes changes on a very short timescale, obtaining reliable inversion results will require modifications to current techniques
Collective Behavior in Few-Fermion Systems
Full text linkThis thesis reports on the exploration of collective behavior in a system of few fermionic atoms.
Access to both real- and momentum space observables in combination with a high degree of
control over both particle number and interaction strength allows us to explore the emergence
of collective behavior from the bottom up - atom by atom.
Inspired by observations in high-energy physics, where hydrodynamic behavior is present in
absence of a separation of scales, we explore interaction-driven elliptic flow which is commonly
considered a smoking-gun of hydrodynamic behavior. Our measurements reveal elliptic flow in
systems of only six constituents.
Motivated by the formation of pairs of fermionic particles in system with broken translational
symmetry (such as atomic nuclei or ’dirty’ superconductors), where BCS theory does not apply,
we investigate how a spatially varying potential affects pair formation. By altering interaction
strength and particle number, we observe a transition from a regime in which pair formation
is determined by the discrete level structure of the potential to a regime in which the potential
only influences pairing by altering the local density
A Critical Appraisal of Planets Orbiting Giant Stars
Full text linkGiant stars provide a unique opportunity to study planets around intermediate-mass stars
through radial velocity surveys and examine the impact of stellar evolution on planetary
systems. Despite their growing numbers, few planets have been found with very short
or long orbital periods. Furthermore, detections around luminous giants are debated as
intrinsic mechanisms can mimic planetary signals. In this thesis, I rule out two transiting
planet candidates from TESS via spectroscopic follow-up. To address the planet controversy
surrounding luminous giants, I develop the simulation tool pyoscillot, showing that the
radial velocities and activity indicators of the false-positive planet host NGC 4349 No. 127
can be reproduced by a non-radial oscillation model. I further combine data from the Lick,
SONG, and CARMENES spectrographs to analyze ten planet candidates with intermediate
orbital periods. I find that testing an extensive baseline of radial velocities for consistency
with Keplerian orbits is crucial to rule out or confirm planets around luminous giants. While
the signals of seven stars are intrinsically induced, I identify a long-period planet candidate
orbiting HIP 64823. Finally, I present first results of the new échelle spectrograph mounted
at the Waltz telescope at Landessternwarte, Heidelberg, demonstrating its potential for
detecting planets around giants
Chemigenetic photoswitchable systems for fluorescence bioimaging
No full textFluorescence microscopy techniques have significantly advanced our understanding of biological systems, enabling the investigation of numerous cellular processes with high spatiotemporal resolution. Light as a non-invasive stimulus enhances resolution and fosters interest in innovative photoswitchable systems for modern microscopy techniques such as super-resolution microscopy. This technique requires specific fluorophores that can switch between fluorescent and non-fluorescent states. In the past decade, significant efforts have focused on developing light-responsive fluorescent proteins and small-molecule fluorophores. While fluorescent proteins are genetically encodable, they often exhibit low brightness and photostability, particularly in the far-red region. Conversely, synthetic small-molecule fluorophores generally show superior optical properties but their applications in living cells are limited, due to a lack of reversible and controllable systems.
In this thesis, I present novel approaches for the spatial and temporal control of fluorescence by designing systems that utilize bright, fluorogenic rhodamine derivatives in conjunction with the self-labelling protein HaloTag. By incorporating a light-responsive moiety into this hybrid scaffold, I demonstrate the potential for reversible modulation of the fluorophore's emission. I explored two strategies: one employing small-molecule photoswitches (azobenzenes) and the other utilizing genetically encoded photoswitchable proteins (AsLOV2). Although I achieved proof-of-principle for reversible fluorescence modulation upon illumination, all azobenzene-rhodamine dyads exhibited strong fluorescence quenching, which limited their utility in fluorescence microscopy applications. A more promising approach emerged by incorporating the AsLOV2 domain into HaloTag. I engineered various photoswitchable proteins and identified candidates that exhibited reversible far-red fluorescence turn-on upon illumination. These engineered proteins were successfully demonstrated in mammalian cells across various targets, achieving a several-fold increase in fluorescence upon illumination. These results suggest that this system holds promise for super-resolution imaging by allowing fine control over the blinking behavior of self-blinking dyes.
Additionally, I explored an application of photoresponsive systems using a recently introduced photoclick reaction to enable highly multiplexed optical labelling in living cells with high spatiotemporal control. This approach facilitates on-demand marking of specific cells or subcellular features for real-time tracking and analysis of their dynamics. Currently, this is achievable using photoactivatable synthetic dyes or proteins, however, such methods are limited to single-color experiments. To address these limitations, I developed photoclickable ligands for HaloTag and SNAP-tag that can covalently bind to clickable fluorophores upon illumination. These newly developed probes show high performance in vitro, in E. coli, and on the surface of living mammalian cells, demonstrating effective light-controlled fluorescence labelling.
Keywords: fluorescence microscopy, photoswitch, fluorophore, rhodamine, HaloTa
Role of Sphingolipid-interacting Proteins in Influenza A Virus Infection
No full textInfluenza A virus (IAV) is a significant cause of respiratory infections globally, with thousands
of casualties annually. Its capacity for rapid antigenic variation in the surface glycoproteins,
hemagglutinin (HA), and neuraminidase (NA) leads to the emergence of novel viral subtypes,
thereby undermining vaccine efficacy and reinforcing its clinical relevance. During viral
budding in polarized cells, IAV utilizes lipid raFs - membrane microdomains enriched in
cholesterol and sphingolipids (SLs) - at the apical side of the cell membrane, resulting in a viral
envelope enriched in these lipids. HA and NA, are characterized as raft-associated proteins,
which are likely recruited to these domains during viral assembly. The NA1 protein, in
particular, might possess an SL-interac9ng motif, potentially aiding its localization to the
budding site. Additionally, the number of SLs increases during IAV infection, and defects in
sphingomyelin (SM) synthesis affect the localization of viral glycoproteins to the plasma
membrane.
Despite the established role of SLs in IAV infection, the precise molecular mechanisms by
which specific SLs contribute to viral propagation, or how IAV modulates the SL metabolic
pathway, remain elusive. The involvement of SL-binding host proteins in viral replication has
not yet been thoroughly explored. To address this, a stable isotope labeling by amino acids in
cell culture (SILAC) proteomics approach was employed, using bifunctional sphingosine to
identify SL-interacting proteins in infected and non-infected A549 cells (AG Brügger). Several
SL-interacting protein hits were selected for further investigation in IAV infection based on
their functional relevance and existing literature evidence of their roles in various viral
infections. Knockdown experiments assessed the impact of several candidate proteins on IAV
infection. Among these, ceramide synthase 2 (CerS2) was identified as a key protein with
potential antiviral effect. CerS2 catalyzes the transfer of an acyl chain from acyl-CoA to a
sphingoid base, with a high selectivity for very long-chain fatty acids. Infection of two
A549ΔCerS2 clones with the PR8 strain of IAV displayed increased levels of viral nucleoprotein
(NP) expression and plaque titers, with some clonal differences in HA titer. Notably, the reexpression of CerS2 in the A549ΔCerS2 cells led to a significant reduction in NP expression, HA
titers, and plaque formation, supporting the hypothesis of an antiviral function for CerS2 in
IAV infection. However, the molecular mechanisms through which CerS2 influences IAV
infection remain to be elucidated in future studies. In summary, this study provides novel
insights into the role of sphingolipid-interacting proteins, particularly CerS2, in the replication
and pathogenesis of IAV. These findings open new avenues for future research and may
contribute to the development of innovative therapeutic strategies aimed at combating IAV
infectio
The Impact of Adenosine mRNA Modifications on Macrophage Function
No full textMacrophages are innate immune cells characterized by a high level of plasticity, which enables their quick adaptation to a changing environment required for initiating, promoting, and resolving inflammatory processes to protect from external threats and maintain tissue homeostasis. Such reprogramming cannot be achieved via transcriptional changes alone, and therefore RNA modifications on macrophages’ transcripts play a crucial role in allowing such versatility needed for a fast and adaptive response. Utilizing the mouse macrophage cell line RAW 264.7 (RAW) as a model system, I investigated the impact of METTL3-mediated m6A and ADAR1-mediated adenosine-to-inosine (A-to-I) editing on macrophage pro- inflammatory activation and immune function. Mapping A-to-I editing sites using short-read Illumina sequencing and m6A using single molecule Nanopore sequencing in RAW macrophages with wild-type genotype or genetic defects in Adar1 or Mettl3, I identified RNA modification sites on more than half of the genes that are involved in macrophages’ immunological functions. Gene expression analysis revealed that loss of m6A induced innate immune sensing, whereas loss of A-to-I editing dampened innate immune activation in macrophages. Additionally, transcriptomic analysis identified ADAR1’s and METTL3’s crucial role in macrophage activation in response to pro-inflammatory stimuli. Using functional assays, I confirmed METTL3’s and ADAR1’s impact on macrophage activation such as the upregulation and presentation of immunostimulatory cell surface markers and phagocytosis activity. While m6A levels remained mostly stable upon ADAR1 depletion, loss of METTL3 globally decreased A-to-I editing levels after pro-inflammatory stimulation. Besides the regulatory effect of some m6A sites on the Adar1 transcript that impact Adar1’s splicing and translation into protein, I found a positive association between A-to-I and m6A sites in transcripts where the modifications were placed at a distance above 139 nucleotides, suggesting a role of m6A in supporting ADAR1-mediated editing. Using a reporter assay for targeted ADAR1 editing, I observed increased ADAR1 recruitment and editing when ADAR1- engaging guide RNAs contained m6A modifications as compared to unmodified guide RNAs. Collectively, the demonstrated interdependency between m6A and A-to-I RNA modifications holds potential to advance therapeutic RNA editing strategies in the future