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De rol en de betekenis van de openbare orde in het burgerlijk procesrecht : een zwanenzang
No full textAbstract: De aard van de rechtsregels was lange tijd bepalend voor de omvang van de taak van de feitenrechter om er ambtshalve toepassing van te maken. In een klassieke leer mocht de rechter enkel rechtsregels van openbare orde ambtshalve toepassen, zelfs wanneer partijen de toepassing ervan hadden uitgesloten. Sedert 2005 wijzigde het Hof van Cassatie zijn rechtspraak op dit punt voor wat betreft het materi\ueble recht. De aard van de materieelrechtelijke rechtsregel biedt niet langer het antwoord op de vraag of de rechter er ambtshalve toepassing van moet maken. Het antwoord op deze vraag vindt men aan de hand van de intensiteit waarmee partijen feiten in het debat brachten. De rechter is sedert 2005 namelijk verplicht om ambtshalve toepassing te maken van de rechtsregels waartoe de in het bijzonder aangevoerde feiten tot staving van de eis aanleiding gaven. Deze evolutie ging voorbij aan de rechtsregels van procesrecht. Wanneer de proceswet geen eigen handhavingsleer op sanctieregeling voorschrijft, doet de rechtspraak nog steeds een beroep op de drieledige indeling van de rechtsregels om uit te maken of de rechter deze of gene rechtsregel van procesrecht ambtshalve moet toepassen dan wel er geen ambtshalve toepassing van mag maken. De aard van de rechtsregel bleef ook na 2005 van belang in het raam van het leerstuk van de ambtshalve toepassing van rechtsregels. Sedert 2008 voltrok zich een belangwekkende wijziging in de rechtspraak van het Hof van Cassatie voor wat de rechtsregels van procesrecht betreft. Hoewel de eiseres tot cassatie een middel afleidde uit de miskenning van een rechtsregel van procesrecht van openbare orde, ging het hof niet over tot de vernietiging van de bestreden rechterlijke uitspraak, omdat deze uitspraak in overeenstemming met de conclusie van de eiseres tot cassatie was gewezen. De rechtspraak wekt verwondering op, aangezien het Hof van Cassatie in de mogelijkheid verkeerde om de miskenning van een rechtsregel van openbare orde te verhelpen, maar dit niet deed. Hoewel deze rechtspraak goedkeuring verdient, valt zij onmogelijk in te passen in de klassieke leer van de openbare orde, de drieledige indeling van de rechtsregels en de procesrechtelijke gevolgen ervan. Om die reden moet de toepassing van voornoemde \u2013 veeleer privaatrechtelijke \u2013 leerstukken in het procesrecht in twijfel worden getrokken. Onderzoek van de belangrijkste rechtsregels van procesrecht wijst uit dat de rechtspraak deze rechtsregels doorgaans onderbracht in de drieledige indeling van de rechtsregels, louter met het oog op de realisering van de procesrechtelijke gevolgen die een klassieke leer aan deze of gene kwalificatie verbond. Vanuit een conceptuele invalshoek, valt de kwalificatie van een rechtsregel van procesrecht als van openbare orde, aanvullend of louter dwingend recht doorgaans niet te verantwoorden. Het alternatief is een eigen ge\uefndividualiseerde handhavingsleer en sanctieregeling voor rechtsregels van formeel procesrecht die een rechterlijke plicht tot ambtshalve toepassing van de rechtsregel verzoent met de rechtspraak van het Hof van Cassatie dat partijen geen cassatiemiddel kunnen afleiden uit de miskenning van een rechtsregel van procesrecht wanneer de bestreden beslissing in overeenstemming met hun conclusie werd gewezen. Deze ge\uefndividualiseerde handhavingsleer en sanctieregeling dient uit te gaan van een unitaire opvatting van de proceswet en kan enkel door een ingrijpen van de wetgever tot stand komen
The search for a stochastic gravitational-wave background with the global LIGO-Virgo-KAGRA detector network and its implications
No full textAbstract: The detection of gravitational waves is a relatively recent and novel way to probe the Universe. They are detected via a global network of laser interferometers operated by the LIGO-Virgo-KAGRA Collaboration, and arise in multiple different forms. To date, one type of gravitational waves has already been observed: transient signals from compact binary coalescences, such as binary black hole and binary neutron star mergers. In this work, however, we search for the stochastic gravitational-wave background, which is the superposition of all gravitational-wave signals that are not detected individually or are unresolvable. Such a background may come from sources with either astrophysical or cosmological origin across a broad frequency range. Observing the background would provide unparalleled information about processes in the early Universe, like inflation, or about populations of astrophysical objects spread out throughout cosmic history. Hence, the primary objective of this thesis is exploring the isotropic search for the stochastic gravitational-wave background using data from the first four observing runs of the LVK network. We, together with collaborators, have introduced a new analysis software tool to further improve and speed up the time required to perform the analysis. Additionally, we explore the implications of a joint analysis that combines the results from the search for the stochastic background with the currently observed gravitational-wave transient events to examine whether the data contain evidence for any variation in redshift of the mass distribution of binary black holes. We end this work by considering the impact of seismic and magnetic noise generated by trains on the sensitivity of the laser interferometers. Indeed, without knowledge of the noise in the detectors, we would not be able to accurately observe gravitational waves and estimate the parameters of their sources
Logistics-anchored attribution for cross-border e-commerce : a Belgian case study
No full textAbstract: Definitions and statistics for (cross-border) e-commerce remain unsettled, and common proxies, corporate headquarters or website domains, do not track where fulfilment value is created. We propose a logistics-anchored attribution rule that classifies business-to-consumer transactions by the country of the last value-adding node immediately before last-mile injection (storage, pick/pack, labelling, quality control, returns triage). Using a common 2022 firm dataset for Belgium, we compare three approaches: headquarters-based, web-domain-based, and our logistics-anchored rule, while holding market totals, marketplace splits, and coverage constant and triangulating operations through twenty expert interviews. Across methods, Belgium\u2019s e-commerce is predominantly cross-border. The preferred logistics-anchored estimate attributes roughly one quarter of spend to domestic fulfilment and three quarters to cross-border nodes, concentrated in The Netherlands and Germany. Interviews link this pattern to higher labour costs, historically tighter evening/night-work rules, and platform consolidation that places pick/pack capacity just across the border. The results show how method choice alone shifts headline shares and why an attribution tied to fulfilment location provides a more operationally faithful and policy-relevant view than headquarters or domain proxies. The approach is portable: with firm-level revenues, a standardised marketplace treatment (1P, 3P platform-fulfilled, 3P seller-fulfilled), and targeted operational triangulation, other countries can replicate the exercise to better align e-commerce measurement with physical flows and last-mile impacts
The political economy of urban land access in eastern DRC : between accumulation, authority fragmentation and militarisation
No full textAbstract: In rapidly growing cities in Africa, the land question is largely characterised by uncertain land rights. Researchers have examined the processes of claim-making to understand how claims to land rights are challenged, enforced and upheld. This thesis contributes to this discourse by examining the motivations, interests and behaviours that underpin the actions of the various parties involved in land affairs, building on the particularity of cities under protracted conflicts. The thesis illustrates entanglements between the reconfiguration of urban spaces and the intersection of war and rapid urbanisation in reinterpreting land rights. Methodologically, two of the largest cities of eastern DRC, namely Goma and Bukavu, whereby rapid urbanisation is intimately connected to war dynamics are used as case studies. First, I engage in a quantitative comparative analysis between these two cities and other major cities in the DRC in terms of housing and household wellbeing. Then, I carry out three in-depth qualitative case studies to examine the political economy of urban land access. I focus on how public authority fragmentation, identity narratives and militarisation processes become critical in determining who has access to land. Drawing on access theory, this dissertation identifies several mechanisms that enable various actors to turn access privileges into benefits. These include identity claims based on autochthony, access to state institutions, knowledge of speculative land markets, the financial capacity to fund land deals and the use or threat of violence, particularly under rebel governance and in situations of militarised land conflict. The increasing privatisation of state land through violent and non-violent land grabs, in a context of fragmented authority, emphasises the importance of state access and coercion in enabling dispossession. These mechanisms facilitate wealth accumulation via clientelist and patronage networks associated with state actors and militarised governance that promote private rent-seeking. The thesis discusses how engaging with the concept of primitive accumulation can help to interpret the observed dynamics within a wider political economy perspective. It demonstrates that processes of accumulation are observed even when urbanisation occurs without substantive economic transformation. Cities affected by long-term conflicts are not just chaotic places; they are also important sites of accumulation and thereby revealing proto-capitalist dynamics. As calls for land reforms continue to increase in Africa, reformers should be aware that many important actors that form the urban fabric actually benefit from the status quo that they are seeking to address. Policy interventions are discussed in the conclusion
From street grinders to city dwellers : the narrative representation of the liberal urban ideal in the early children's books of Abraham Hans, 1900-1914
No full textAbstract: Current historiography typically characterizes the Flemish Movement\u2019s cultural production during the Belle \uc9poque as conservative and anti-urban. Literature is often treated as a means of constructing a shared Flemish identity rooted in a rural idyll and traditional values. This view, however, overlooks the ideological diversity within the Flemish Movement. A smaller but active liberal faction saw the city as a positive symbol of industrialization and modernization and advocated reform of the city and its inhabitants in accordance with the bourgeois ideal of self-discipline and knowledge. This article seeks to nuance the dominant perspective by examining the representation of the Flemish city in the early children\u2019s works of the explicitly liberal flamingant Abraham Hans. While the role of children\u2019s literature in the formation of a Flemish identity has largely been overlooked, this genre offers valuable insights into the national and ideological discourses of the time. The formative power of children\u2019s literature was widely acknowledged among Flemish pedagogues and writers of the period, including Hans, who sought to \u201celevate\u201d young Flemish citizens through \u201cgood books.\u201d His preference for contemporary urban settings and his narrative treatment of urban space reflect a positive, future-oriented urban ideal intended to socialize young readers into the values and norms of respectable Flemish citizenship. In doing so, his work aligns with the broader liberal \u201ccivilizing offensive.\u201
Opportunities and limitations of mild reductive treatments for the synthesis of coloured TiO2 with applications in gas sorption and photocatalysis
No full textAbstract: Titanium dioxide is widely used in photocatalysis because it is abundant, stable, and inexpensive, yet pristine anatase and rutile absorb mainly ultraviolet light. One strategy to extend activity into the visible region is the introduction of sub-gap states associated with oxygen vacancies and Ti\ub3\u207a species. These are typically generated through hydrogenation, high-temperature reduction, plasma treatment, or strong chemical reductants, routes that often raise energy concerns. This thesis therefore addresses a practical question: can TiO2 be reduced by mild and potentially scalable methods that still deliver useful functionality under realistic conditions, and where do such approaches succeed or fail? High-intensity ultrasound was first investigated as a potential reduction route. Using calorimetrically calibrated power delivery and systematic probe integrity checks, any apparent darkening of TiO2 during aqueous sonication was traced to metallic debris from horn erosion rather than defect formation. UV\u2013Vis diffuse reflectance showed no band-edge shift or sub-gap absorption, and no evidence for stable oxygen vacancies or Ti3+ species was found. Under these conditions, cavitation hot spots do not provide a sustained reducing environment, and any transient defects are likely rapidly re-oxidised by radical species and dissolved oxygen. Ultrasound-induced \u201cblackening\u201d is therefore an artefact rather than a viable reduction strategy. Despite this negative outcome, ultrasound proved valuable as a synthesis and processing tool. During sol\u2013gel synthesis it yielded high-surface-area, texturally open amorphous TiO2 with interconnected nanoparticulate networks. Controlled ultrasonic crystallisation produced anatase while retaining about 50% of the surface area, compared to the 10% of conventional calcination. These materials showed rapid uptake of volatile organic compounds, consistent with their preserved open structure. Vacuum annealing was then explored as a hydrogen-free route to defective TiO2. Mild vacuum treatment of P25 darkened the powder, increased visible-light absorption without shifting the band edge, and shifted the Ti:O ratio away from perfect stoichiometry. Functionally, this resulted in an approximately 25% increase in methane formation during CO2 photoreduction compared with pristine P25. Applying the same treatment to Au@P25 preserved plasmonic properties but provided only marginal additional activity beyond that already conferred by gold. Overall, this work shows that mild routes give mild but reliable outcomes. They are effective for preserving structure, adsorption capacity, and stability, and can deliver meaningful functional gains in selected cases
Peasants into stewards : leasehold between profit, power, and nature in the Low Countries, 1200-1400
No full textAbstract: This research examined short-term leasing in the Low Countries between 1200 and 1400. From the thirteenth century onward, leasehold became the dominant form of land management, and it is usually associated with profit maximisation and risk management. This study also highlights its role in sustainable management of natural resources by linking medieval leasing practices to the modern concept of environmental stewardship, understood as the responsible management of natural resources by temporary users. Lease contracts contained a wide range of clauses regulating land use and natural resources. By analysing these provisions, the research investigated how profit-seeking, risk mitigation, and environmental management interact within leasing systems across five regions: Inland Flanders, Coastal Flanders, Artois\u2013Cambr\ue9sis, Li\ue8ge, and the Dutch River Area. The thesis is structured in three parts. The first examines the contracts themselves, looking at their legal status, normative character, and the legal and cultural expectations embedded in the contracts. The second part analyses lease prices, their regional variation and development, and relations between lessees and lessors. The third focuses on environmental clauses concerning the management of land, flora, and water infrastructure, and their evolution over time. The findings contribute to four debates. First, the research suggests that leasing emerged earlier than previously assumed, with private individuals also active on the lease market quite early. Second, lease prices revise our understanding of the Late Medieval crisis: with new insights into the impact and timeline of the crisis. Third, the contracts reveal how profit-seeking, risk mitigation, and environmental management were structurally intertwined. Fourth, leasing had a clear ecological dimension, as contracts could encourage sustainable land use, even if primarily driven by non-ecological interests of lessors. Finally, the study reflects on the contemporary ecological crisis and modern lease legislation. Medieval contracts demonstrate that legal frameworks can promote responsible engagement with natural resources. Today, however, such a framework is largely absent, resulting in the underutilisation of leasing as an instrument for maintaining soil quality
Development of methods for detection of infectious hepatitis E virus in pork meat products and optimization of processing practices to reduce infectivity
No full textAbstract: Hepatitis E Virus (HEV) poses a significant public health risk in Europe, particularly through the consumption of contaminated pork products. With increasing concern about foodborne transmission, understanding the persistence of HEV in meat products is crucial for improving food safety and preventing infections. This thesis investigates HEV in a Belgian context, with the primary aim of enhancing knowledge of HEV survival in pork meat products. The first part of the study involved conducting risk analyses to identify which pork products present the highest risk of HEV infection for consumers. The findings revealed that ready-to-eat pork products carry the greatest theoretical risk, leading to the sampling and testing of these products from Belgian supermarkets for the presence of HEV RNA. HEV RNA was detected in 65% of the tested samples, particularly in pork liver p\ue2t\ue9s, confirming the presence of HEV in pork products available for sale. The second part of the project focused on developing and refining methods to detect HEV in meat products. Existing detection methods are labor-intensive, not standardized, and often fail to extract intact viral particles. The goal was to 1) optimize a cell culture model for directly assessing infectivity and 2) develop proxy methods for evaluating HEV infectivity indirectly by assessing the intactness of viral particles. Afterwards we optimized an extraction method that successfully retrieved intact and infectious HEV from pork products, enabling differentiation between infectious and inactivated HEV\u2014a capability lacking in current RT-qPCR methods. In the final part of this project, the optimized methods were used to assess the impact of common meat processing techniques on HEV infectivity. Pork liver p\ue2t\ue9s were made to evaluate the effects of heat treatment, showing that HEV is remarkably heat-stable, requiring temperatures up to 99C for complete inactivation (>3.5 log reduction). Similarly, dried pork sausages were used to study the effects of drying and pH reduction, revealing that HEV remains stable for up to 14 days, with pH reduction having very limited effect on inactivation. These findings indicate that current meat processing techniques may be inadequate for fully inactivating HEV, leaving residual infectious virus in pork products available for sale. This underscores the potential risk of foodborne HEV infection from consuming these products. In summary, this project provided the first comprehensive demonstration of HEV presence in Belgian meat products, alongside the development and optimization of methods for detecting infectious HEV. Additionally, the study assessed the effects of thermal processing, pH reduction, and drying on HEV survival, offering valuable insights into the persistence of the virus during meat processing and emphasizing the need for improved food safety practices
Development of sustainable catalytic methods : aza-cope rearrangement of homoallylamines and thiosulfonylation of alkenes
No full textAbstract: A major issue within chemistry is the use of expensive, non-renewable and toxic reagents/reactants, catalysts or solvents to carry out organic reactions. The replacement of these by inexpensive, abundant and benign alternatives is an ongoing challenge for the chemical community. The research of this doctoral thesis is focused on the development of novel sustainable methodologies for the synthesis of \u3b1-substituted homoallylamines via 2-aza-Cope rearrangement and subsequent functionalization of its alkene moiety via visible light photocatalysis. \u3b1-Substituted homoallylamines are valuable synthetic building blocks and precursors for the synthesis of a variety of nitrogen containing heterocycles, natural products and pharmaceutical compounds in organic synthesis and medicinal chemistry. In this doctoral thesis, a metal-free or base-metal-catalyzed 2-aza-Cope rearrangement strategy has been developed for the synthesis of \u3b1-substituted homoallylamines by using easily accessible aldehydes and 1,1-diphenylhomoallylamines. Alkenes are one of the most fundamental functional groups in organic chemistry and are often derived from simple chemical feedstock. In the past few decades, the functionalization of alkenes has caught tremendous attention, especially strategies to achieve functionalization in an anti-Markovnikov manner were the focus of fundamental research. The installation of sulfonyl (R1SO2-) and sulfenyl (R2S 12) moieties specifically is of application interest as they appear in natural products, bioactive molecules, and pharmaceuticals. Besides, they are attractive functionalities in organic synthesis as they are easily transformed into other functional groups. Direct functionalization methods of alkenes, which allow to introduce two different groups in a single reaction step such as the thiosulfonylation are therefore highly desired. In this doctoral thesis, a metal-free methodology for the vicinal thiosulfonylation of unactivated alkenes has been developed by using thiosulfonates as a reactant and the acridinium salt 9-mesityl-10-methylacridinium perchlorate as a photo-organocatalyst with visible-light irradiation. To illustrate the synthetic potential, the method was applied for homoallylamines and late stage functionalization of olefins in active pharmaceutical ingredients