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Biodeterioration of the historical buildings in Lake Tana and the response of the stakeholders : the case of Narga Selassie Monastery
No full textAbstract: Lake Tana, Ethiopia\u2019s largest lake, hosts numerous culturally significant structures, including Narga Selassie Monastery built in the 18th century on Dek Island. This study examines the biodeterioration affecting the monastery\u2019s historic buildings, biological degradation caused by microorganisms such as fungi, lichens, and mosses, and evaluates the roles of stakeholders in its preservation. Field surveys, visual inspections, and stakeholder interviews reveal extensive biological colonization exacerbated by poor drainage and vegetation overgrowth, leading to physical damage such as discoloration, cracks, and mortar decay. Despite recognition of its cultural value, current conservation efforts by the Ethiopian Orthodox Church, local communities, and government bodies are fragmented and constrained by limited expertise, funding, and coordination. The study advocates for an integrated and participatory conservation framework that merges traditional practices with scientific monitoring approaches to ensure sustainable preservation of Narga Selassie and other built heritage in the lake
From PDF to preservation : using automated text analysis to uncover stone use motivations in 19th century public architecture
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Unequal burden : inguinal sentinel lymph node biopsy and the disproportionate risk of infection in melanoma
No full textAbstract: Aim To evaluate surgical site-specific infection rates after sentinel lymph node biopsies (SLNB) for melanoma. Methods This single-centre retrospective analysis of prospectively collected data included 422 patients who underwent SLNB between January 2020 and January 2025. Negative post-operative outcomes within 31 days were recorded: infection, seroma, wound dehiscence, haematoma, lymphedema and other complications. Clinical variables included: demographics, SLNB site and result, comorbidity, prophylactic antibiotic use and American Joint Committee on Cancer stage. Multivariable logistic regression was used to identify predictors of infection. This study adheres to the STROBE guidelines (Supplementary Appendix). Results Across the 422 patients in the cohort (mean age 59.1 years, range 6\u201389 years), infection accounted for 55 cases (13%). Rates varied markedly by site: inguinal 23.9%, axilla 7.8%, knee 29.4% and head/neck 3.0%. All infections were managed with antibiotics, and none required re\u2011operation. Multivariable analysis revealed that inguinal site (OR 5.01, 95% CI 2.50\u201310.04, p < 0.001) and male gender (OR 2.57, 95% CI 1.30\u20135.09, p = 0.007) independently predicted postoperative infection. Age and comorbidity were not associated with increased risk in our cohort. Conclusion Within this UK cohort, the SLNB anatomical site emerged as the strongest driver of postoperative infection, with inguinal procedures carrying the greatest increase in risk. Male patients were also at a higher risk of infection. These findings highlight the value of targeted prevention strategies and close postoperative surveillance for high-risk groups
Ecological and social determinants of dengue and chikungunya along an altitudinal gradient in Central Nepal
No full textAbstract: Climate change is increasingly influencing the epidemiology of vector-borne diseases (VBDs) in the Hindu Kush Himalayan (HKH) region, with significant implications for public health. This PhD research examines the ecological and social determinants of dengue and chikungunya along an altitudinal gradient in Central Nepal, addressing critical evidence gaps related to climate change, disease distribution, and community responses across different elevations. A concurrent cross-sectional mixed-methods approach was conducted between September and October 2018, integrating quantitative household surveys (n = 660) and qualitative data from 27 in-depth interviews and 12 focus group discussions. The study was guided by four research objectives: (RO1) assessment of climate trends and community perceptions, (RO2) spatiotemporal distribution of dengue and chikungunya, (RO3) community knowledge, attitudes, and practices (KAP) related to dengue, and (RO4) challenges in vector control implementation. Results show a strong agreement between perceived and observed climate trends, particularly increasing summer temperatures (p < 0.001), while perceptions of rainfall variability differed significantly by altitude (p < 0.001). Communities across all elevation zones reported increasing climate-related extreme events, including floods, droughts, and landslides, with perceived impacts on agriculture, water resources, biodiversity, and human health. The systematic review of 66 studies revealed substantial geographic expansion of dengue and chikungunya across the HKH region, with Nepal accounting for the highest proportion of reported dengue cases (56.83%), peaking during the post-monsoon (September-November). Household survey findings indicate low dengue awareness and limited preventive practices, despite generally positive attitudes. Education and income were positively associated with knowledge (p < 0.01). Qualitative findings highlighted growing concern among stakeholders regarding future dengue risk due to climate change and human mobility. Vector control efforts were found largely reactive, outbreak-oriented, and constrained by limited resources, weak coordination, and insufficient community engagement. This thesis demonstrates that climate change is reshaping dengue risks along Nepal\u2019s altitudinal gradient, while highlighting that chikungunya is an emerging regional threat in the HKH. The findings underscore the necessity for climate-informed, region-specific public health policies, strengthened surveillance, and targeted awareness programs to improve preparedness for climate-sensitive health threats in Nepal and the HKH region
Fostering technological change through regulations conducive to responsible mining of ocean mineral resources
No full textAbstract: Metal demand continues to increase due to rising global population, urbanisation, and to meet society\u2019s clean energy goals. Polymetallic nodules are rock concretions (the size of tennis balls) consisting largely out of minerals. They are found in the Pacific Ocean at 4,500 meters water depth. It is estimated that these nodules contain more nickel, cobalt and manganese than all land-based reserves combined. By 2020, the UN International Seabed Authority (ISA) will deliver the world\u2019s first set of exploitation regulations for polymetallic nodules found on the seabed of the area beyond national jurisdiction (\u201cthe Area\u201d). The ISA, an intergovernmental body to manage all mineral-related activities in the Area, was established by the Law of the Sea Convention (LOSC) in 1994. The LOSC designates its resources as the common heritage of (hu)mankind and calls for the development of the resources (by attracting investment and technology), and the protection of the marine environment for the benefit of (hu)mankind. Under an exploitation contract, contractors receive the right to exploit polymetallic nodules in return for a payment, which must be fair for both the ISA and the contractor. The ISA must ensure these proceeds are equitably shared among all members taking into particular consideration the interests and needs of developing States. This dissertation provides valuable insights into the interaction between regulatory development and the impact on a contractors\u2019 decision to invest in new \u201cbiased\u201d technological change (i.e., technological change that lowers the environmental impact relative to the status quo), thereby contributing to the awareness of the ISA. The author hereby focusses on the five-year multi-stakeholder participation process (2015-2019), that led to the draft exploitation code. After section one offers a general introduction, section two provides a synthesis of workshop proceedings, ISA technical papers and scholarly literature, offering more detail on the multi-stakeholder process that led to a payment system. In section three, a stochastic techno-economic assessment is delivered to model the impact of different payment rates on the economic performance of a polymetallic mining project. In section four, a risk assessment evaluates the financial, technical & institutional risks and provides insights into the minimum (private) financial return required to attract investment. Chapter five analyses different technology and environmental policy instruments that foster biased technological change. Finally, the author concludes with new insights on the impact of the proposed regulations on technological change required for responsible deep sea mining
Underground connections : the interplay between tropical rainforest trees and soil microbial communities
No full textAbstract: Tropical rainforests host an exceptional biodiversity and play a fundamental role in the regulation of global climatic cycles. Soil fungi and bacteria are key players in the transformation and processing of nutrients in terrestrial ecosystems while having an essential role as tree mutualists or antagonists. Still, there are gaps in our understanding of the main variables driving soil microbes on these forests and it is unclear how future climate change scenarios may impact soil microbes and further affect the ecosystem. In this thesis, we first explored the drivers of the microbial community composition in two pristine forests in French Guiana by using amplicon DNA sequencing. The neighboring tree species were found to be a crucial factor influencing the fungal and bacterial community composition at our sites regardless of the season. Additionally, within the environmental factors explored, soil moisture, phosphorus (P) and nitrogen (N) availability were consistently the main soil properties controlling the composition of soil microbial communities. Secondly, as increased nutrient deposition due to anthropogenic activities are expected to affect tropical forests ecosystems N and P availability, a factorial N and P nutrient addition experiment in the same sites was used to assess the effects of changes in the soil nutrient stoichiometry on the soil microbial communities. These results showed that after 3 years of nutrient additions, the bacterial and fungal community composition was affected by both the N and P additions. Besides, the fungal community composition had a stronger response to the nutrient addition, especially when P was added. Moreover, when the nutrient addition effect was assessed in bacteria and fungi with different life strategies, we found different nutrient optima between them. Furthermore, to study the effect of the connection to an existing mycorrhizal mycelium on tree seedlings, I established a mycelium exclusion experiment. Interestingly, we could not detect an effect of the mycorrhizal mycelium exclusion on the seedling N uptake, performance, or fungal community composition in roots after one year. All together this work provides a deeper understanding of the factors influencing the soil microbial communities on these lowland tropical forests, demonstrating that the tree community composition exerts a higher influence on the soil microbial community composition than previously expected. Moreover, our results show that the fungal and bacterial community composition and its relationship with trees in the vicinity is highly dependent on the ecosystem nutrient availability
Slack resources as anchors or accelerators in strategic changes : family ownership as a moderator
No full textAbstract: Whether slack resources inhibit or facilitate SMEs to introduce strategic changes is an unresolved question. We investigate how different bundles of financial and human resource (HR) slack relate to strategic changes, and how this relation is influenced by the presence of family majority ownership. We survey 654 private Belgian SMEs and find, in line with the slack-as-resources for change perspective, that non-family-owned SMEs introduce the fewest strategic changes when they bundle low levels of financial slack with low levels of HR slack, while they undertake the most strategic changes when they bundle high levels of financial slack with low levels of HR slack. Family ownership moderates this relationship, as strategic decision-making in family-owned SMEs follows the behavioral agency model. As such, the effect of slack resources in family-owned firms is best described by the slack-as-a-buffer perspective, and the bundle of high levels of financial slack with low levels of HR slack results in fewer strategic changes rather than more
Learning from rural-urban stations : strategies for rail-based development in a low-density Flemish landscape
No full textAbstract: This paper examines the potential of transit-oriented development (TOD) in low-density landscapes. We explore rail-based investments in rural-urban areas through context-specific research-by-design methods, using the railway line between Antwerp and Ghent in Belgium as a case study. Comparative analysis of student-produced designs, based on train mobility scenarios, reveals three key strategies: multimodality, landscape as a structuring element and rural-urban functional mix. They showcase the ability to increase stations\u2019 catchment areas and ridership by capitalizing on the specificity of the rural-urban context, increasing active transportation modes and recreational and touristic value. They provide valuable insights for sustainable development in low-density landscapes, enriching the discourse on mainstream TOD planning
(In)visible and (in)vincible? Designing theory-based, evidence-based, and strategic communication materials to increase radon protection intentions
No full textAbstract: Radon, a naturally occurring radioactive gas, is the second leading cause of lung cancer worldwide. Despite the severe health risks, radon testing and mitigation remain insufficient. This issue is situated on multiple levels, ranging from the individual to the political, economic, social, and physical environment. While effective communication is essential to bridge this gap, radon health communication remains underexplored. This dissertation examines how strategic, theory- and evidence-based communication can enhance public engagement with radon-related behaviours. In the first phase of this research, the current communication was analysed. A systematic review of radon-related mass media interventions reveals that most campaigns rely on informational messaging, often failing to evoke personal relevance or emotional engagement. Moreover, in focus group workshops homeowners emphasised the need for communication strategies that extend beyond awareness-raising, addressing practical concerns such as financial support and regulatory measures. Participants also suggest tailoring messages to different behavioural stages, using approaches such as humour, personal letters, and testimonials. In the second phase, communication materials were developed and tested. An online experiment compared the impact of narrative-based and statistical messages on risk perception and behavioural intentions. Findings indicate that narratives are more effective in increasing personal and general risk perception while also strengthening intentions to seek information, test for radon, and consider mitigation. These results inform the development of a large-scale social media campaign, Radon Buster, designed to motivate individuals to take action. The campaign, implemented across Austria, Belgium, Ireland, and Slovenia, uses Facebook ads incorporating narratives, humour, and social norm nudges to attract attention and drive engagement. A controlled online survey experiment finds that exposure to these ads positively influences information-seeking intentions. A subsequent live Facebook study demonstrates strong audience engagement, with click-through rates and interaction metrics suggesting that social media can serve as an effective platform for radon risk communication. Overall, the findings highlight that radon communication must go beyond merely providing information, but should engage audiences, and align the messages with the decision-making process. While no one-size-fits-all solution exists, integrating social, emotional, and cognitive factors can enhance the effectiveness of communication strategies. This dissertation underscores the importance of a multi-level approach, combining stakeholder-targeted messaging with broader environmental interventions to ensure radon risk communication translates into meaningful action