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Buitenlandse investeringen en nationale veiligheid: een vergelijkende juridische studie over de balans tussen veiligheidsbelangen en economische vrijheid binnen het investeringsscreeningskader in Europa en de Verenigde Staten
No full textThe project of global economic liberalization, with the aim to provide for economies open to trade and investment, is in distress. The use of trade and investment by foreign states for political ends resulted into the introduction of security concerns in foreign and domestic economic policy. The European Union and its various Member States, traditionally supporters of an open market economy and a bastion of free trade, have not been immune to events where the effects of economic interaction with third countries proved to be detrimental rather than beneficial. Especially in times of crises, economic dependency on third countries and their companies have been cause for concern. The recent policy shift in the United States under the Trump administration demonstrates that even one of Europe's long-standing allies may turn into an economic foe in a relatively short period of time.
On the European side, policy- and lawmakers did not remain passive. Especially in the area of foreign investment, the EU is becoming more assertive in controlling Foreign Direct Investment (FDI) as the narrative concerning these international flows of capital has altered. In particular, the perception and appreciation of FDI has changed due to the increasing awareness of the risks it entails for 'national security' and 'public order'. This is even more notable when the investment involves a strategic undertaking.
Across the European Union, foreign investment screening mechanisms have only recently made their debut as a general instrument of investment policy. Rest assured, these mechanisms are here to stay. This thesis seeks to gain a better understanding of the legal design of the investment screening framework in the EU and its Member States in order to determine what it can or cannot accomplish, and in turn, what it should be able to accomplish. In particular, the framework has a dual objective. The explicit objective is defined as 'the ability of the framework to maximally allow a government to identify FDI-associated risks to national security, and to take appropriate measures to mitigate those risks'. The implicit objective can be defined as 'the capacity of the framework to safeguard investment freedom to the greatest extent possible, while ensuring that the rights and legitimate expectations of foreign investors are respected'. The challenge is how to reconcile this dual objective in the design and the operation of investment screening mechanisms. This thesis attempts to answer how the design of an investment screening mechanism can best incorporate these interests, and whether trade-offs have to be made. The ultimate goal of this thesis is to examine how the framework can be improved in both the short and long term, and to identify the key issues that have to be resolved in order to achieve a balanced and reliable framework.
This project starts from the assumption that the current legal framework is suboptimal. The legal framework for investment screening is not uniform, but fragmented and complex. The main reason for this is that the competences that are relevant in order to screen FDI with the intention to mitigate security risks are dispersed among European Union and Member State levels of government. The result is a patchwork of national screening mechanisms that are similar in concept but different in scope. On top of this, the European Union adopted Regulation (EU) 2019/452 that establishes a framework for the screening of foreign direct investments into the Union. This regulation - for now - mainly concerns the coordination and cooperation between the Member States when screening FDI. In essence, the EU and Member States mutually restrict each other's ability to shape the investment screening framework. Furthermore, international law also plays a role.
Is it possible to improve this framework? This thesis aims to present policy- and lawmakers with an analysis of how the current framework achieves these objectives, and what options are available to improve the framework for it to advance both objectives. The work is structured in four titles.
A first title aims to understand why investment screening mechanisms have been introduced by describing and exploring the policy context. The ultimate objective of this title is to provide the reader a nuanced picture of investment screening mechanisms, not only as laws, but also as a political instrument of geostrategic policy. A second title explains what investment control mechanisms are and how they function. A first chapter discusses the investment screening framework on the European level. A second chapter focusses on the screening mechanisms of four Member States: Germany, France, the Netherlands and Belgium. Furthermore, this title probes into the national and supranational rules that establish the legal limitations that the EU and - especially - its Member States have to take into account when developing the investment screening framework.
A third title engages in a comparative analysis of national investment screening laws. In particular, the objective of this title is to discuss how the positive legal rules in contemporary investment screening laws can be adapted in order to advance the explicit objective and the implicit objective. In a first step, the selected European jurisdictions are compared and structurally evaluated. In a second step, the investment screening rules of the European Member States are compared with those of the United States. The latter has been operating an investment screening mechanism before any European initiative existed. It presents a distinct approach to some of the fundamental features of investment screening, which allows to contemplate which lessons can be drawn from a mature investment screening regime. After a discussion of the positive rules themselves, this thesis turns to a discussion of the broader legal context in which those rules came into existence. The final title of this thesis addresses several 'foundational' challenges confronting the investment screening framework in the EU and its Member States. There are two issues that are discussed In a first chapter, the thesis discusses the challenge of competence allocation between the EU and its Member States, i.e. an intra-European context. In a second chapter, this thesis discusses the challenges for the investment screening framework in the relation of the EU and its Member States with third countries, i.e. an international legal context.status: Publishe
Gendered Social Media Content Among Adolescent Boys and Girls: Findings from a Data Donation Linkage Study on Instagram, TikTok, and Snapchat
No full textsponsorship: European Research Council|852317status: Published onlin
Nieuwe inzichten in de levertransplantatie: Optimalisatie van revalidatie voor betere uitkomsten
No full textLiver transplantation constitutes the only curative treatment for patients with end-stage liver disease. Advances in the field have led to favourable short- and medium term (1-3 year) post-transplant survival rates, but improvement in long-term survival rates remains disappointing. Due to the immunosuppressive therapy, a sedentary lifestyle and a poor recovery of post-transplant physical fitness, the proportion of liver transplant recipients who develop a new-onset or a deteriorating unfavourable cardiovascular risk profile is alarmingly high, and cardiovascular disease is the leading cause of death in this population. By consequence, in order to improve long-term outcome after liver transplantation, prevention of cardiovascular disease should be prioritized. We are convinced that the challenge of cardiovascular disease and lack of physical fitness in liver transplant recipients should and can be addressed by subjecting these patients to a structured physical rehabilitation program. The aim of this project is implement a structured, individually-tailored, home-based but supervised physical rehabilitation and maintenance program for de novo liver transplantation recipients, and to demonstrate the feasibility and safety of such approach as well as its efficacy to improve physical fitness. The program will consist of a 2-phase intervention of i) home-based exercise training (aerobic exercise training as well as strength, flexibility and stability exercises under in-person and subsequently remote guidance) and ii) an 18-month maintenance phase of physical activity. This program will be studied in an open-label randomized trial where the regimen will be compared with a regimen of standard of posttransplant care. In addition to the interventional arm, two different regimens of exercise training intensity will also be studied.status: Accepte
Embracing ethnic diversity benefits everyone: How most pluralist, some color-blind, but no assimilationist practices relate to higher belonging and achievement in primary school students
No full textsponsorship: Research Foundation - Flanders (FWO)|G067020Nstatus: Accepte
GEAVANCEERDE ANALYSE VAN COLONMOTILITEIT BIJ STOORNISSEN VAN DE DARM-HERSEN INTERACTIE Een multimodale benadering met behulp van hoge-resolutie colomanometrie, registratie van elektrische signalen uit het colon aan het lichaamsoppervlak en magnetische resonantie beeldvorming met symptoomcorrelatie
No full textColonic function is impaired in functional bowel disorders (FBDs), which are characterized by disordered bowel movements (diarrhoea, constipation) and pain, discomfort and bloating. The most important FBDs are functional constipation, chronic diarrhea and the irritable bowel syndrome. We hypothesize that contractions of the colon and their control are disturbed in FBDs, and that this explains their symptoms both in terms of disordered bowel movements and abdominal pain/discomfort/bloating. We will use high resolution manometry, a new tool which uses a sophisticated series pressure-sensitive sensors on a tube, to unravel motor patterns in the different FBDs in comparison to healthy volunteers, and we will study the relationship between symptom occurrence and changes in these motility patterns. We will also take biopsies and will analyse surgical specimens to study changes in the nervous system and the pacemaker cells of the bowel that provide the normal control of bowel motility. In preliminary studies we have seen activation of immune cells in the colon of patients with very severe constipation and this was associated with loss of normal neural function. We will expand these observations and study the correlations to determine whether immune activation is the mechanism that leads to these disturbances.status: Publishe
De impact van kiemen of hydrothermaal behandelen van tarwe op ijzer en zink biobeschikbaarheid
No full textWheat is a widespread staple crop and a dominant source of energy and minerals for humans. Particularly the aleurone layer of the miller's bran is rich in iron (Fe) and zinc (Zn) and accounts for most of their content in whole wheat (20 - 35 mg/kg). For the human body to fully benefit from the minerals, they need to be bioavailable. Mineral bioavailability refers to the fraction of minerals that is absorbed in the intestinal lumen and enters the systemic circulation to exert bioactivity in the human body. The key minimum requirement for bioavailability is bioaccessibility, which is the extent to which minerals are released from their matrix in the gastrointestinal tract. Unfortunately, the bioaccessibility of wheat Fe and Zn is only 3 - 5%. This is mainly due to their chelation with phytic acid. As these chelates (i.e. phytates) are insoluble at intestinal pH, and because intestinal phytate-degrading enzymes (i.e. phytases) only have limited activity, these minerals in wheat are not bioaccessible.
Unit operations that target increased phytase activity in wheat can be effective at increasing mineral bioaccessibility. During steeping and sprouting of wheat, phytase is activated and de novo synthesized. As a result, phytate is broken down, and previously bound minerals are released. Another relevant unit operation is hydrothermal processing, in which wheat grains are incubated under low pH and high temperature conditions that allow endogenous phytase activity. In addition, complexes formed during wheat processing (e.g. with acetate, lactate, or citrate) may further enhance mineral bioaccessibility.
Prior to this work, it was unclear whether these unit operations, which increase Fe and Zn bioaccessibility in wheat, also enhance Fe and Zn bioavailability. To address this knowledge gap, the overall objective of this work was to investigate the effect of sprouting or hydrothermal processing of wheat on Fe and Zn bioavailability using both in vitro and in vivo approaches.
In the first part, the effect of steeping and sprouting of wheat on its phytate content and Fe and Zn bioaccessibility was investigated. Strong positive correlations were observed between sprouting time, phytate reduction, and Fe and Zn bioaccessibility. Steeping (36 h, 15 °C) and sprouting (48 - 120 h, 26 °C) of wheat caused significant phytate breakdown (25 - 40%), accompanied by a 1.5 to 2.7-fold increase in Fe bioaccessibility and a 1.6 to 2.3-fold increase in Zn bioaccessibility, expressed relative to the total mineral content in wheat. However, long sprouting times (at least 48 h) and substantial phytate reduction were required to significantly increase Fe and Zn bioaccessibility.
Furthermore, a multifactorial experiment in which grains were subjected to various combinations of incubation time, temperature, pH, and medium revealed that hydrothermal processing of wheat at 60 °C and pH 4.0 led to maximal phytate breakdown. The incubation medium significantly affected the extent of phytate reduction: processing in acetate or lactate buffer reduced the phytate content maximally by 54% and 61%, respectively, while using a citrate buffer achieved a maximal reduction of only 42%. Surprisingly, despite substantial phytate reduction in wheat processed in acetate or lactate buffer, Fe and Zn bioaccessibility did not differ markedly from those of untreated wheat. In contrast, hydrothermal processing (60 °C, pH 4.0) of wheat using citrate buffer increased bioaccessibility by factors 9.8 (Fe) and 8.8 (Zn) times, probably due to the formation of soluble mineral-citrate chelates.
In the second part, the effects of sprouting or hydrothermal processing of wheat on Fe and Zn bioavailability were estimated using Caco-2 cells, a model system for intestinal absorption. Interestingly, sprouting wheat for up to 120 h did not affect Fe Caco-2 bioavailability, expressed relative to the total mineral content in wheat, while that of Zn was slightly higher than that of non-sprouted wheat. These findings indicate that, although sprouting increased Fe and Zn concentrations in in vitro digests, their uptake by Caco-2 cells, expressed as a fraction of bioaccessible mineral, was negatively affected. As non-labile Fe and Zn complexes may negatively affect their uptake by Caco-2 cells, the lability of bioaccessible Fe and Zn was examined using diffusive gradients in thin films (DGT). It was concluded that sprouted wheat contains non-labile Zn complexes, and that sprouting for more than 72 h leads to the formation of substantial fractions of non-labile Fe complexes. This may partly account for the lack of enhancement in Fe and Zn bioavailability to Caco-2 cells observed in sprouted wheat.
Hydrothermal processing (60 °C, pH 4.0) of wheat using a citrate buffer increased Caco-2 bioavailability of Fe and Zn, by 6 and 12-fold, respectively, expressed relative to the total mineral content in wheat. This hydrothermal process did not affect the uptake of Fe and Zn by Caco-2 cells, expressed as a fraction of bioaccessible mineral. Analyses of the DGT-lability of in vitro digests showed that Fe chelates, such as Fe-citrate chelates, present in in vitro digests of hydrothermally processed wheat were sufficiently labile to contribute to increased Fe bioavailability. Most Zn in the in vitro digests was present as free ions or in labile chelates, although a small fraction remained non-labile, which may partially limit enhancements in Zn bioavailability.
In the final part, the actual Zn bioavailability of breakfast flakes produced from untreated, sprouted, and hydrothermally processed wheat was measured in humans using a dual-isotope tracer technique with extrinsically labeled stable isotopes. Despite a 1.4-fold increase in Zn bioaccessibility following steeping (36 h, 15 °C) and sprouting (48 h, 26 °C), neither fractional Zn absorption (expressed relative to the total Zn content in wheat flakes) nor total Zn absorption (i.e. the amount of absorbed Zn) increased in human subjects (n = 24). Hydrothermal processing (pH 4.0, 60 °C) of wheat using citrate buffer increased fractional Zn absorption by a modest factor 1.1. However, total Zn absorption did not differ significantly between regular flakes and those made from hydrothermally processed wheat. These limited increases in Zn absorption were likely attributable to residual phytate levels, physiological regulation of Zn absorption in non-deficient human subjects, and the presence of non-labile Zn complexes.
In conclusion, steeping and sprouting, and hydrothermal processing of wheat using citrate buffer effectively increase Fe and Zn bioaccessibility. However, steeping and sprouting did not enhance Fe Caco-2 bioavailability, and only prolonged sprouting modestly improved Zn Caco-2 bioavailability. Similarly, the fractional and total Zn absorption measured in human subjects was not increased by steeping (36 h, 15 °C) and sprouting (48 h, 26 °C). Hydrothermal processing (pH 4.0, 60 °C) of wheat using citrate buffer largely enhanced Fe and Zn bioaccessibility and Caco-2 bioavailability, likely due to the formation of soluble and labile mineral-citrate chelates. The human intervention study confirmed that the treatment resulted in a modest increase in fractional Zn absorption and no increase in total Zn absorption.
Overall, phytate content is a major, but not the sole, determinant of mineral bioaccessibility and bioavailability in wheat. Even when phytate content is substantially reduced, other factors may still limit mineral bioavailability. Furthermore, combining the DGT technique with Caco-2 cell models provides valuable and complementary insights into mineral bioavailability. This work provides in-depth insights into how unit operations impact Fe and Zn bioavailability, contributing to the production and consumption of foods with improved nutritional quality, ultimately benefiting public health.status: Accepte
Analyse van het effect van de aan Parkinson-gelinkte VPS35 mutatie op mitofagie
No full textParkinson's disease (PD) is the most common neurodegenerative movement disorder with a strongly increasing prevalence. No cure for PD exists yet. Therefore, it is important to further elucidate the pathogenic mechanisms of PD. A minority of PD cases have a monogenic cause. VPS35, LRRK2 and SNCA are genes linked to autosomal dominant PD. VPS35 is part of the retromer complex, which mediates the retrograde transport of proteins from the endosomal network to either the trans-Golgi network or the plasma membrane. The p.D620N missense mutation is the only known pathogenic mutation in VPS35. The molecular mechanisms by which this VPS35 mutation induces neurodegeneration are still unclear. Several monogenic causes of PD (PINK1, PRKN, LRRK2 mutations) have already been shown to disrupt the process of selective degradation of damaged mitochondria (mitophagy). The aim of this PhD is to investigate the possible role of wild-type VPS35 in mitophagy and the impact of the p.D620N mutation on this pathway. The experiments will be performed in patient and control skin fibroblasts, iPSC-derived dopaminergic neurons and Drosophila melanogaster.status: Publishe
Globale Oplossing voor Problemen in Systeemidentificatie en Modelreductie
No full textSystems theory provides a mathematical framework for describing dynamical phenomena through the abstract notion of a ``system''. Such a system is typically described by differential (continuous-time) or difference (discrete-time) equations that govern the evolution of internal states, and their relationship to inputs and outputs, over time. The abstract notion of a system makes it applicable across a wide range of disciplines: systems may represent physical entities, such as industrial processes, biological networks, or mechanical structures, but equally abstract constructs in economics or sociology. The obtained mathematical models form the basis for analysis, simulation, prediction, and control, the latter of which refers to the manipulation of the system's inputs to achieve certain objectives (e.g., stabilization, trajectory tracking or disturbance rejection).
This dissertation addresses two closely related topics: system identification, the task of inferring dynamical models from observed data, and model reduction, the approximation of a given high-order model by a model of lower complexity. Both problems naturally lead to non-convex optimization formulations, even when restricted to linear model classes. Consequently, the state of the art is dominated by iterative approaches that compute (at best) locally optimal solutions. While such methods are highly effective in engineering practice, they leave important questions unresolved: global optimality cannot be guaranteed, so one is never certain whether even better solutions exist, the outcome often depends strongly on the chosen initialization, and reproducibility is not always guaranteed. From a mathematical standpoint, these problems can therefore not yet be considered ``solved.''
In this dissertation, we develop a novel deterministic methodology that leads to globally optimal solutions. We specifically focus on the (weighted) least squares realization problem for identifying autonomous linear time-invariant models and the single-input single-output H2-norm model reduction problem. The key insight is that, for both problems, the first-order optimality conditions can be expressed in polynomial form, with their real common roots fully characterizing the set of (local) minimizers. By exploiting the partially linear structure, we reformulate the polynomial system as a multiparameter eigenvalue problem (MEP), which generalizes the standard eigenvalue problem by allowing more than one spectral parameter and removing the restriction of linearity in its parameter(s). The solutions of these MEPs, the so-called eigentuples, contain the globally minimizing solutions of the original problem.
The proposed framework is powerful in that it provides a unified methodology for two problems that are closely related yet fundamentally distinct. The resulting formulations also represent a substantial advancement over the state of the art in globally optimal approaches, both in terms of improved computational efficiency as theoretical simplicity. Finally, the contributions are non-trivial: in particular, the role of Walsh's Theorem as an important building block in the development of globally optimal solution methods had not previously been recognized.
The pursuit of global optimality, however, comes at a considerable computational cost. The efficiency of the proposed methodologies is governed by the difficulty of computing all common roots of the system of polynomial equations, or equivalently, the eigentuples of the resulting MEPs, the number of which grows rapidly with the problem size. For this reason, the proposed framework is best viewed as a theoretical benchmark, rather than a practical tool for large-scale applications. To better understand these computational limitations, we present an algebro-geometric analysis of the solution sets of the obtained MEPs. This comprehensive analysis, which forms our second main contribution, leads to novel insights into the solution set to the critical equations. Most notably, we establish reducedness of the solutions of the MEPs (i.e., each solution occurs with multiplicity one) and, through the Thom--Porteous formula, we derive exact solution counts.status: Accepte
Optimalisatie van distaal bovenste lidmaat anesthesie en analgesie.
No full textThe overall aim of this PhD project is to evaluate the quality of anaesthesia for distal upper extremity surgery and to design and test strategies to further optimise analgesia and anaesthesia of the distal upper extremity.status: Accepte
Availability of Multi-Infeed Industrial LVDC Grids with Multiple Zones Considering Timely Protection
No full textThe paper explores the reliability and availability of low-voltage direct current systems in industrial settings. The paper introduces a methodology that uses semi-Markov processes and universal generating operators to assess system performance. The impact of various protection devices on system availability and reliability is evaluated. Key findings highlight the benefits of combining different protection devices for cost-effective fault clearance, the impact of protection failure, and the advantages but also the sensitivities of splitting the DC bus into multiple zones to enhance system robustness. The analysis is made freely available as part of the Julia package MultiStateSystems.jlsponsorship: This work is funded by Vlaio and Flux50 (http://www.vlaio.be, http://www.flux50.be)status: Published onlin