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The role of supporting ligands in Ruthenium-mediated ethenolysis reactions
No full textCatalyst stability is one of many challenges encountered in olefin metathesis. Herein, we probe the behavior of first and second-generation alkene metathesis catalysts as a function of pressure and temperature in the ethenolysis of polybutadiene. Experimental data indicates that increased steric hindrance on the ancillary ligand tends to reduce decomposition pathways, as emphasized by the decrease of activity at high pressure and temperature with the SIMes ligand compared to SIPr.sponsorship: We gratefully thank the Research Foundation - Flanders (FWO) and the Special Research Fund (BOF) of Ghent University (starting and senior grants to S.P.N.) . Umicore AG is gratefully thanked for gifts of materials. C.V. and D. D. V. wish to thank the KU Leuven for IBOF project IBOF/21/016 and D.D.V. is grateful to FWO for project funding G0D3721N. (Research Foundation - Flanders (FWO), Special Research Fund (BOF) of Ghent University, KU Leuven for IBOF project|IBOF/21/016, FWO|G0D3721N)status: Publishe
Van Hellenistische tafelwaar tot Romeins keizerlijke en vroeg-Byzantijnse Sagalassos Red Slip Ware: een diachronische studie naar fijn aardewerk uit Sagalassos (ZW-Anatolië) door middel van een archeometrische en experimentele benadering
No full textThis thesis presents a diachronic examination of tableware production at the site of Sagalassos (SW Anatolia), from Hellenistic to Early Byzantine times. Located on the slopes of the Western Taurus Mountain range, Sagalassos was involved in a long tradition of ceramic production going back to late Achaemenid times and thus offers the opportunity to examine local tableware production in a longue durée perspective. Building upon previous research on ceramics from Sagalassos, this thesis reconstructs the local ceramic technologies over time shedding light on different aspects of their chaînes opératoires, ranging from the procurement of clay raw materials to slip preparation.
This long-term examination involved the archaeometric study of a large number of samples (n=172) of table wares dating to the different chronological phases of the site's occupational history and belonging to the characteristic wares of each period. Τhin section ceramic petrography and bulk geochemical analysis using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) were employed for the characterisation of the ceramic bodies of the samples. Their associated slip layers were examined in terms of microstructure and chemical composition using Scanning Electron Microscopy coupled with an Energy Dispersive Spectrometer (SEM-EDS). In addition, an experimental approach using clays from the territory of Sagalassos was also employed offering new insights into clay refinement processes and slip preparation techniques for the production of Sagalassos Red Slip Ware (SRSW).
The results demonstrate a high degree of continuity of the potting tradition of Sagalassos over time, at least concerning some aspects of the chaîne opératoire, and reflect the presence of a long-lasting, established ceramic tradition at the site which is based on the potters' technological and empirical knowledge of the properties of the locally available raw materials. SRSW appears as a continuation of the pre-existing Hellenistic tradition in slipped pottery following similar technological choices in terms of the clay raw materials used. For over a millennium of local production and despite changes in the location of the ceramic workshops over time, the potters of Sagalassos consistently selected the clays from the Çanaklı valley for the ceramic body of tableware and a different type of clay for slip production, possibly deriving from the weathering of the ophiolitic bedrock at the site. Although locally produced tableware followed the general trends in pottery style of the Eastern Mediterranean during the different chronological periods into question forming part of a ceramic koine, the technology of their production appears as a continuation of a long-lasting potting tradition. At the same time, the identification of additional fabrics in the material under study which are made using different raw materials than the mass-produced SRSW, albeit their macroscopic similarity to SRSW, suggests the possible presence of other eastern sigillata workshops in accordance with the concept of ceramic koine.
Using the site of Sagalassos as a case-study, this research has shown the importance of the analytical examination of pottery in a longue durée perspective in order to reconstruct ceramic technologies over time and obtain a more comprehensive understanding of aspects of ceramic production during changing sociopolitical contexts.status: Publishe
Industrial symbiosis in aluminium parts manufacturing: Towards 100 % material efficiency by combining friction stir extrusion and molten metal deposition
No full textsponsorship: We gratefully acknowledge contributions outside of the list of authors by ValCUN and the University of Palermo. This research was partially funded by SIM Flanders (ICON project Green AM; project number HBC.2020.2952). Special thanks goes out to Michael Hauschild for his valuable feedback on LCA and methodology. (SIM Flanders (ICON)|HBC.2020.2952)status: Publishe
Essays in Digital Economics
No full textDigital aggregator platforms shape content markets through design choices that govern discovery, feedback, and access. This dissertation uses quasi-experimental variation to estimate how platform design, and design responses to regulation, affect content visibility, participation, demand, and downstream outcomes.
Chapter 2 studies YouTube's removal of public dislike counts. Before the change, women received more dislikes than men for comparable content. After the change, the gender gap disappears because dislikes fall more for women, with effects concentrated in the upper tail, consistent with reduced herding that enabled dislike attacks. This reduction in negative feedback increases female creators' output and demand for their content.
Chapter 3 examines Google News' response to Australia's News Media Bargaining Code using scraped data and a difference-in-differences design. I show that regulation-induced changes in relative content costs led Google News to substitute toward displaying more content from foreign outlets and smaller domestic publishers that were relatively cheaper, particularly in prominent slots and in topics with many substitutes (such as global news).
Chapter 4 analyzes Facebook's sudden one-week news ban in Australia. The ban sharply reduced social media traffic to news websites, driven by reliable outlets and hard news (politics and the economy), with limited effects on misinformation-flagged sites and soft news (sports and entertainment). Districts more reliant on Facebook for news subsequently shift votes away from informal ballots and major parties toward minor parties in the 2021 Western Australian state election, with turnout unchanged under compulsory voting.
Overall, the evidence shows that platform governance and regulation can reallocate attention across producers and content types and can affect political behavior, with policy impacts shaped by platforms' ability to re-optimize content display.status: Publishe
Reversal of third-degree AV block with ruxolitinib in VEXAS-associated myocarditis: a case report.
No full textBACKGROUND: VEXAS syndrome is a newly described autoinflammatory condition; cardiac involvement is exceedingly rare. This case illustrates a reversible complete heart block due to myocarditis in VEXAS, successfully treated with targeted therapy. CASE SUMMARY: A 69-year-old man with known VEXAS syndrome presented with dizziness and syncope. Workup revealed third-degree atrioventricular (AV) block and imaging consistent with myocarditis. Standard therapy (atropine, isoprenaline infusion) stabilized the patient, and ruxolitinib (a JAK inhibitor) was initiated alongside corticosteroids to treat the underlying inflammatory syndrome. Within days, the patient's AV conduction was restored without the need for pacemaker insertion. He was discharged with improved cardiac function and ongoing immunomodulatory therapy. DISCUSSION: Targeted immunomodulation can reverse cardiac conduction block caused by inflammation in VEXAS syndrome. This case underscores the importance of recognizing autoinflammatory syndromes as a cause of heart block and suggests a potential role for JAK inhibitors in treating inflammatory myocarditis.status: Published onlin
Digital Interventions Targeting Healthy and Sustainable Eating Behavior: Systematic Review and Meta-Analysis.
No full textBACKGROUND: Current food consumption patterns contribute to the rising prevalence of obesity and noncommunicable diseases and exacerbate environmental degradation. Digital media offer promising opportunities to promote healthier and more sustainable eating; yet, evidence regarding their effectiveness remains fragmented. OBJECTIVE: The aim of this systematic review and meta-analysis is (1) to evaluate the effectiveness of digital interventions in improving healthy and sustainable food consumption and (2) to identify which participant and intervention characteristics are associated with greater effectiveness. METHODS: A systematic search was conducted in January 2024 and repeated in September 2025 across Web of Science, Embase, and Scopus, supplemented with forward and backward reference searching. Eligible studies were those with a quasi-experimental or longitudinal design evaluating digital interventions targeting nonclinical populations, with the aim of increasing plant-based food consumption or reducing animal-based food intake. Risk of bias was assessed using the Cochrane risk-of-bias tool. Included interventions were coded for behavior change techniques using the Behavior Change Taxonomy version 1. A random-effects meta-analysis with robust variance estimation was performed, and moderator analyses were conducted with participant and intervention characteristics. RESULTS: Eligibility screening led to the inclusion of 52 papers published between 2004 and 2025, with 24,652 participants in total. The meta-analysis revealed a small but statistically significant positive effect of digital interventions on food consumption outcomes (d=0.33, 95% CI 0.25-0.42; P<.001). However, substantial heterogeneity (I2=86%, 95% prediction interval -0.21 to 0.87) indicates considerable variation in effectiveness across intervention characteristics. A moderator analysis showed no significant difference in effectiveness (P=.53) between interventions aimed at reducing meat consumption (d=0.38, 95% CI 0.20-0.57; P<.001) and those promoting plant-based eating (d=0.33, 95% CI 0.23-0.42; P<.001). Although digital interventions had the strongest effects among young adults (d=0.46, 95% CI 0.30-0.61; P<.001), age-related differences were not statistically significant. Intervention effectiveness differed significantly by platform (P=.03), with social media interventions (d=0.65, 95% CI 0.41-0.90; P<.001) yielding stronger effects than other modalities. Incorporating prompts or cues significantly enhanced effectiveness (d=0.58 vs d=0.30; P=.04). Although not statistically significant, interventions including social support or behavioral comparison (both d=0.39; P<.001) yielded larger effects. Few studies included adolescents or individuals from lower socioeconomic backgrounds. CONCLUSIONS: This review underscores the innovative potential of digital interventions in improving eating behavior, highlighting how effectiveness varies by intervention design. Social media emerge as particularly promising, likely due to their unique social and interactive features. By pinpointing the contexts and types of digital interventions that most effectively promote plant-based eating, this study provides timely guidance for researchers and practitioners in increasingly digitalized food environments. Nonetheless, more high-quality studies are needed to confirm these insights and address the critical gap among adolescents and low socioeconomic groups.status: Published onlin
Biallelic variants in COX18 cause a mitochondrial disorder primarily manifesting as peripheral neuropathy
No full textDefects in mitochondrial dynamics are a common cause of Charcot-Marie-Tooth disease (CMT), whereas primary deficiencies in the mitochondrial respiratory chain (MRC) are rare and atypical for this aetiology. This study aims to report COX18 as a novel CMT-causing gene. This gene encodes an assembly factor of mitochondrial Complex IV that translocates the C-terminal tail of MTCO2 across the mitochondrial inner membrane. Exome sequencing was performed in four affected individuals from three families. The patients and available family members underwent thorough neurological and electrophysiological assessment. The impact of one of the identified variants on splicing, protein levels and mitochondrial bioenergetics was investigated in patient-derived lymphoblasts. The functionality of the mutant protein was assessed using a proteinase K protection assay and immunoblotting. Neuronal relevance of COX18 was assessed in a Drosophila melanogaster knockdown model. Exome sequencing coupled with homozygosity mapping revealed a homozygous splice variant c.435-6A>G in COX18 in two siblings with early-onset progressive axonal sensorimotor peripheral neuropathy. By querying external databases, we identified two additional families with rare deleterious biallelic variants in COX18. All eight affected individuals presented with axonal CMT, and some patients also exhibited CNS symptoms, such as dystonia and spasticity. Functional characterization of the c.435-6A>G variant demonstrated that it leads to the expression of an alternative transcript that lacks exon 2, resulting in a stable but defective COX18 isoform. The mutant protein impairs Complex IV assembly and activity, leading to a reduction in mitochondrial membrane potential. Downregulation of the COX18 homologue in D. melanogaster resulted in signs of neurodegeneration, including locomotor deficit and progressive axonal degeneration of sensory neurons. Our study presents genetic and functional evidence that supports COX18 as a newly identified gene candidate for autosomal recessive axonal CMT with or without CNS involvement. These findings emphasize the significance of peripheral neuropathy within the spectrum of primary mitochondrial disorders, in addition to the role of mitochondrial Complex IV in the development of CMT. Our research has important implications for the diagnostic work-up of CMT patients.sponsorship: This work was supported in part by the Fonds Wetenschappelijk Onderzoek (FWO-Flanders) (research grants G048220N and G0A2122N to A.J.; doctoral grants to D.A., L.M., L.V.deV. and S.A.B.), the Research Fund of Universiteit Antwerpen (doctoral grant to C.A.), the Association Belge contre les Maladies Neuro-Musculaires (ABMM-Telethon) (research grants to A.J. and S.A.B.), the French Muscular Dystrophy Association (AFM-Telethon, research grant 23708 to A.J., TRAMPOLINE grant 28730 to S.A.B.). This study makes use of data shared/provided through RD-Connect, which received funding from the European Union Seventh Framework Programme (FP7 Health/2007-2013) under grant agreement no. 305444. This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under grant agreement no. 779257 (Solve-RD). M.M.R. acknowledges funding from the Medical Research Council (MRC MR/S005021/1), Wellcome Trust (G104817), National Institutes of Neurological Diseases and Stroke (NINDS) (U54NS065712 and 1UOINS109403-01), Muscular Dystrophy Association (MDA510281), Charcot Marie Tooth Association (CMTA) and the Harrington Discovery Institute. This research was also supported by the University College London Hospitals (UCLH) Biomedical Research Centre. (Association Belge contre les Maladies Neuromusculaires', French Muscular Dystrophy Association|23708, European Union Seventh Framework Programme|FP7/2007-2013, European Union Seventh Framework Programme|305444, Muscular Dystrophy Association|MDA510281, the National Institute for Health Research University College London Hospitals Biomedical Research Centre, National Institutes of Neurological Diseases and Stroke and office of Rare Diseases|U54NS065712, National Institutes of Neurological Diseases and Stroke and office of Rare Diseases|1UOINS109403-01, Charcot Marie Tooth Association, Medical Research Council|MRC MR/S005021/1, Research Fund of the University of Antwerp, Harrington Discovery Institute, European Union's Horizon 2020 research and innovation programme|779257, Fund for Scientific Research|G048220N, Fund for Scientific Research|G0A2122N, Wellcome Trust|G104817)status: Published onlin
TROPICCAL: Multi-perspective trace clustering for IoT-enhanced processes
No full textBusiness processes (BPs) that are enhanced with Internet of Things (IoT) technology, such as smart manufacturing processes, leverage IoT devices like sensors to monitor and capture contextual data from the physical environments where processes are executed. While the execution of BPs is typically recorded in information systems as event logs, IoT-enhanced BPs also produce IoT data that can offer valuable contextual insights. However, existing process mining techniques, which typically focus on the control-flow perspective, often miss key insights into the dynamic interplay of process activity sequences and IoT data—such as how certain IoT readings may trigger or affect specific process activities. To address this gap, we propose TROPICCAL, a new technique for multi-perspective trace clustering that integrates three key perspectives: the control-flow perspective, the trace attribute data perspective, and the time series (TS) sensor data perspective. The main novelty of TROPICCAL is the analysis of so-called context events as part of the TS data perspective. These events mark process-significant happenings detected in the TS sensor data. Furthermore, in order to unravel more insights from the output of our technique, we propose approaches for cluster explainability based on permutation feature importance. We demonstrate the efficacy of our approach and compare it with the most related and advanced approaches from the literature using a real-world manufacturing use case. Expert evaluation through in-depth interviews reveals that TROPICCAL offers better insights into the multi-perspective variants of the process.sponsorship: Research Foundation (Flanders)|G0B6922Nstatus: Publishe
Pain management after open thoracotomy 2025: procedure-specific postoperative pain management (PROSPECT) recommendations.
No full textINTRODUCTION: Adequate postoperative pain control is crucial for rehabilitation after open thoracotomy. The aim of this systematic review was to update the previous procedure-specific postoperative pain management recommendations for patients undergoing open thoracotomy. METHODS: Using previously reported PROSPECT methodology, we performed a systematic review of randomised controlled trials, systematic reviews and meta-analyses evaluating pain interventions for open thoracotomy published between 2015 and 2024. Data extracted from the included studies were evaluated by an expert subgroup that considered the relevance of the studied interventions in clinical practice and their risk/benefit profile. Recommendations were finalised after review and comments by all members of the PROSPECT working group using a modified Delphi approach. The Cochrane Risk of bias tool 2 was used to grade the quality of evidence. RESULTS: Overall, 100 studies were included. Based on the available evidence, either thoracic epidural analgesia or paravertebral blockade should be provided as a first-line analgesic intervention for open thoracotomy. Erector spinae plane, rhomboid intercostal or intercostal nerve blockade could be used as a second-line regional analgesia intervention. In addition, patients should receive basic analgesia consisting of paracetamol and non-steroidal anti-inflammatory drugs or cyclo-oxygenase-2 selective inhibitors. Acupuncture or cryoanalgesia is recommended when regional analgesia cannot be performed, albeit with a low level of supportive evidence. The choice of surgical technique, postoperative physiotherapy and approach to patient education should be based on outcomes other than pain control. DISCUSSION: In these updated guidelines on pain management after open thoracotomy, the main changes concern the recommendation of either thoracic epidural analgesia or paravertebral blockade as the first-line intervention according to patient and clinician preference, combined with basic systemic analgesia. The use of other regional blocks should be limited to patients who cannot receive thoracic epidural analgesia or paravertebral blockade.sponsorship: European Society of Regional Anaesthesia and Pain Therapystatus: Published onlin
