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Simulatie van bodemverdamping en de relatie met de verrijking van zware waterisotopologen in de bodem met behulp van verschillende modelbenaderingen
No full textUnderstanding water loss through evapotranspiration becomes critical for sustainable water management practices. Despite its importance, significant knowledge gaps remain in modeling and monitoring complex energy and mass transfer processes that drive soil evaporation. Current modeling approaches range from simplified isothermal models to complex non- isothermal multi-phase models with varying degrees of accuracy. Furthermore, field and laboratory measurements face technical challenges, such as capturing diurnal flux variations or controlling experimental conditions in wind tunnel studies. With our research we aimed to address certain limitations by testing and comparing different model approaches against high-frequency laboratory and field measurements. Our goal was to identify under which conditions certain simplifications in evaporation modes are appropriate.status: Accepte
Ontwikkeling van innovatieve multidimensionale vloeistofchromatografiemethoden voor de analyse van organische microverontreinigingen in omgevingswater
No full textThis project aims at developing innovative multi-dimensional liquid chromatography (MD-LC) methods for the simultaneous analysis of compounds of interest in a typical wastewater matrix (inorganic salts, aromatic compounds, organic micropollutants (OMPs) and their transformation products (TPs)). Since these compounds display a variety of physicochemical properties (polarity, functional groups and charge), multiple separation mechanisms are required for their analysis. This project will therefore investigate the feasibility of combining up to four separation mechanisms in a single injection MD-LC method to ensure all relevant compounds can be analyzed. For the characterization of the compounds, a combination of detectors will be used. A non-destructive diode-array detector will be coupled in series with either a conductivity detector for the detection/quantification of inorganic ions or mass spectrometry for the identification/quantification of organic compounds. Once all relevant compounds have been identified, a taxonomically diverse set of aquatic organisms (including zebrafish and Medaka fish) will be used to assess the toxicity/ecotoxicity features of the identified compounds.status: Accepte
Framing of customer feedback by French-speaking service managers on Twitter and how it is perceived
No full textstatus: Accepte
Menselijke darmorganoïden voor onderzoek naar de biologie van enterische virussen en de ontdekking van antivirale medicijnen
No full textDiarrheal diseases have an estimate of 1.7 billion episodes of acute diarrhea annually, being one of the leading causes of mortality in children up to five years of age worldwide. Viral gastroenteritis is the main cause of such diarrhea and is caused by several viruses, from which human norovirus (HNoV) and human rotavirus (HRV) are the main culprits. Despite a high disease burden, there is currently no specific antiviral treatment for viral diarrhea. The inability to cultivate many of these diarrhea-causing viruses in standard cultivation systems has been a major challenge to overcome, which hampers our understanding of many aspects of their biology and consequently the development of antiviral strategies. The recently described human intestinal enteroid model, derived from primary intestinal tissue, has opened the door to studies of in vitro replication and even pathogenesis of many enteric viruses. Enteroids recapitulate the complexity of the human intestinal epithelium and allow the replication of clinically relevant human strains of norovirus and rotavirus.
Given their clinical and highly physiological relevance, compared to standard cell lines, human intestinal organoids are also a valuable in vitro platform to study other enteric viruses such has enterovirus A71 (EV-A71) and hepatitis E virus (HEV).
In Chapter III, we established a robust HNoV infection model using differentiated three-dimension (3D) enteroids. HNoV GII.4 replicated to higher titers in fetal ileum 3D-enteroids in a robust and reproducible manner when compared with the traditional two-dimension (2D) enteroid model. This model allows the generation of spontaneous apical-out HIEs during infection in suspension and is thus suitable for infection with pathogens that infect through the apical side of the intestinal epithelium.
In Chapter IV, we extended the 3D-enteroid infection model to human rotavirus and established an antiviral assay using 3D-enteroids. This model allowed for the first time the assessment of antiviral activity of reference and novel compounds against HNoV and HRV in the same model system. A unique system that can be useful when developing broad-spectrum antivirals against viral diarrhea. Using 3D-enteroids, we determined the anti-norovirus and anti-rotavirus activity of molnupiravir, an approved antiviral for the treatment of Sars-CoV-2 infection, that could be used as compassionate treatment for HNoV or HRV chronically infected patients.
In Chapter V, we established an EV-A71 infection model using human induced pluripotent stem cell-derived human intestinal organoids. Reference antivirals were tested in the intestinal organoid model and rhabdomyosarcoma cells. Overall, two of the three compounds tested in this study show a lower selectivity index in the intestinal organoid model, which is in line with pre-clinical in vivo data for these compounds. This highlights the benefits of a more physiologically relevant in vitro model to assess antiviral activity. Moreover, we established an image-based antiviral assay in intestinal organoids to allow a fast quantification and analysis of key feature of the infected organoids.
In Chapter VI, we established an HEV-enteroid infection model to dissect the role of the gut compartment in HEV infection. We found that HEV replicates efficiently in both mature and immature cell types within the gut and that the progeny virus was released as naked virions. These novel findings highlight the need to further understand the dissemination strategies and pathogenesis of HEV in the gut, and not merely in the liver.
In Chapter VII, the main results from the previous chapters are discussed, presenting the underlying meaning of our research. In conclusion, this work points out the advantages and way forward in using more physiologically relevant preclinical models in antiviral drug discovery and to study virus-host interactions.status: Publishe
Band - wegdekinteractie op een grof wegdek. Inverse reconstructie van band – wegdekcontactkrachten gebruikmakend van numerieke modellering en responsmetingen
No full textThe PhD has developed a combined numerical-experimental approach to calculate the dynamic excitation forces in the footprint when a tire rolls on a rough road. This parameter is directly related to the structural noise radiated by the tire. For this, a reconstruction method is applied, using measured responses to inversely compute the excitation forces. Subsequently, these excitation forces are expressed using a metric that is suitable to rank different tire designs for the dynamic excitation forces. Absolute accuracy is not required as an accurate ranking of the different tire constructions will provide the necessary design information and will aid designers in controlling spindle forces/moments and structural tire noise radiation and efficiently explore the tire design space.status: Publishe
Designing idea contests to optimize the front end of the innovation process.
No full textThe aim of the proposed doctoral research project is therefore to increase the understanding on how companies can adequately design innovation tournaments to optimize their performance in the FFE of the innovation process.status: Publishe
The Interference of Kinshasa’s Citizen-Broadband Communication: Towards an Ethnography of Connectivity
No full textThis chapter provides an ethnographic study of the sociality of citizen broadband radio communication in Kinshasa, capital city of DR Congo. While CB radio technology is rarely used for private communication in the highly technicized countries of the Global North, it is still widely used in Kinshasa and the DRC. I argue that the analysis of contemporary sociality, not only in Kinshasa but anywhere long-distance connectivity is experienced, must acknowledge the role of technological devices in social life, as well as historical shifts in the imagination of connectivity along technological innovations. Technologies, their affordances, as well as the various social worlds they set forth and operate in, all produce new forms of sociality, establish new ways of setting up relationships and of managing relationships. The ethnography of phonie sociality in Kinshasa allows me, first, to theorize on one particular kind of connectivity: “interference”, i.e. the exposure to unwanted, undesired and/or interfering sounds, images, and people; and second, to conceptualize spaces of connectivity as “hotspots” because (a) they connect different space-time configurations; (b) they are often a space of excess of emotions and claim making; (c) and are spaces of linguistic hybridity and cacophony. As we cannot assume universal experiences of living and managing social life in electronic modernity, we need thick descriptions of people and social interaction in other places, other times and using other communication technologies. In particular, we should pay attention to the the layeredness of the established connections, the activities in the sites (even virtual) of connectivity, and the affective dimensions of these spaces and relations. Such an analytic program is required in order to gain deeper insight in the thickening of sociality, affect and technology that make up our times. The chapter thus contributes to social studies of technosociality, material culture, and urban studies.sponsorship: FWO|G.0.E65.14N, FWO|GA00514Nstatus: Accepte
Instrumentele variabele methodes onder afhankelijke censurering
No full textInstrumental variable methods are a popular set of econometric techniques to identify and estimate causal effects. They can however fail when the outcome variable of interest is a duration. For example, consider evaluating the causal effect of a job training service on unemployment duration, where job seekers often stop answering follow-up surveys before they find new employment. In that case, the unemployment duration is said to be right censored by some censoring time. To solve this issue, it is customary to assume that the duration and censoring time are statistically independent of each other. However, this assumption is likely to be violated in the example on job seekers, that is there is dependent censoring. The goal of this PhD project is to develop new instrumental variable methods that are valid under dependent censoring. This research will fill an important gap in the literature on instrumental variable methods for duration outcomes, where the independent censoring assumption is often taken as a given without proper reasoning.status: Publishe
Belichaamde intelligentie voor zachte robots door middel van mechanische instabiliteiten
No full textAdvances in robotics have historically followed progress in digital computation, leading to increasingly powerful centralized control architectures. While effective, this approach contrasts with biological systems, which achieve adaptability and efficiency through decentralized control and tight coupling between morphology, materials, and environmental interaction - an approach known as embodied intelligence. Two fundamental architectural differences underlie this contrast: rigid robots rely on discrete, single-function components, whereas biological systems exhibit continuous morphologies with multifunctional elements.
Soft robots naturally align with biological architectures through their compliance, functional integration, and sensitivity to mechanical interactions. Their ability to undergo large elastic deformations further enables the deliberate exploitation of mechanical instabilities as computational and control resources. This work investigates how such instabilities can be harnessed to shift control functionality from centralized software into the physical body.
Three soft robotic systems are presented. First, a bio-inspired actuation strategy enables rapid, high-energy motion in inflatable actuators by storing elastic energy and releasing it through pressure-triggered mechanical detachment, experimentally demonstrated via repeated jumping. Second, a hybrid electro-pneumatic central pattern generator exploits the mechanical bistability of a truncated conical membrane and a soft strain sensor to generate self-sustained, tunable oscillations with modular control. Third, the Pneumatic Multilevel Schmitt Trigger introduces multilevel pneumatic logic, enabling compact memory, demultiplexing, and oscillatory circuits with increased per-component functional density.
Together, these contributions demonstrate how mechanical instabilities can enhance embodied intelligence, enabling robust, decentralized, and efficient soft robotic systems.status: Publishe