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Hagen, W.R. (author)The development of tungsten biochemistry is sketched from the viewpoint of personal participation. Following its identification as a bio-element, a catalogue of genes, enzymes, and reactions was built up. EPR spectroscopic monitoring of redox states was, and remains, a prominent tool in attempts to understand tungstopterin-based catalysis. A...review 2023
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Hagen, W.R. (author)A broadband EPR spectrometer is an instrument that can be tuned to many microwave frequencies over several octaves. Its purpose is the collection of multi-frequency data, whose global analysis affords interpretation of complex spectra by means of deconvolution of frequency-dependent and frequency-independent interaction terms. Such spectra...journal article 2023
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Enzymatic Birch Reduction via Hydrogen Atom Transfer at an Aqua-Tungsten- bis-Metallopterin CofactorSeelmann, Carola S. (author), Huwiler, Simona G. (author), Culka, Martin (author), Strampraad, M.J.F. (author), Biskup, Till (author), Weber, Stefan (author), Ullmann, G. Matthias (author), Hagedoorn, P.L. (author), Pierik, A.J. (author)The Birch reduction is a widely used synthetic tool to reduce arenes to 1,4-cyclohexadienes. Its harsh cryogenic reaction conditions and the dependence on alkali metals have motivated researchers to explore alternative approaches. In anaerobic aromatic compound degrading microbes, class II benzoyl-coenzyme A (CoA) reductases (BCRs) reduce...journal article 2023
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Hagen, W.R. (author), Louro, Ricardo O. (author)Distances between Fe ions in multiheme cytochromes are sufficiently short to make the intramolecular dipole-dipole interaction between hemes probable. In the analysis of EPR data from cytochromes, this interaction has thus far been ignored under the assumption that spectra are the simple sum of non-interacting components. Here, we use a...journal article 2023
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Hagen, W.R. (author)An EPR spectrometer has been developed that can be tuned to many frequencies in the range of ca 0.1–15 GHz. Applicability has been tested on ferrimyoglobin fluoride (MbF) and ferrimyoglobin cyanide (MbCN). MbF has a high-spin (S = 5/2) spectrum with <sup>19</sup>F superhyperfine splitting that is only resolved in X-band along the heme normal....journal article 2022
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Pipintakos, Georgios (author), Lommaert, Caitlin (author), Varveri, Aikaterini (author), Van den bergh, Wim (author)The ageing of bitumen has received great attention both from a chemical and rheological perspective due to its direct impact on asphalt performance. However, open questions with respect to the convergence of the synchronous ageing changes in rheology and chemistry of bitumen still exist. This paper addresses these alterations of chemistry and...journal article 2022
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Groot, Mira (author)Research background<br/>Plastic debris in the environment consists primarily of plastic consumer waste. One of its leading causes is the lack of waste collection systems in developing countries. Actions need to be taken to overcome this issue, and Extended Producer Responsibility (EPR) seems to be an effective solution for encountering plastic...master thesis 2021
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Pipintakos, Georgios (author), Soenen, Hilde (author), Ching, H. Y.Vincent (author), Velde, Christophe Vande (author), Doorslaer, Sabine Van (author), Lemière, Filip (author), Varveri, Aikaterini (author), Van den bergh, Wim (author)Understanding the fundamental mechanisms of oxidative ageing in bitumen is considered of paramount importance in order to take steps towards durable binders able to tackle distresses related to this phenomenon which deteriorates the asphalt performance. This paper focuses on the identification of the intermediate and final oxygenated products...journal article 2021
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Pipintakos, Georgios (author), Ching, H. Y.Vincent (author), Mühlich, Uwe (author), Soenen, Hilde (author), Van Doorslaer, Sabine (author), Sjövall, Peter (author), Varveri, Aikaterini (author), Vande Velde, Christophe (author), Lu, Xiaohu (author)Oxidative ageing in bituminous materials is considered to be one of the most important factors for distress types in road applications. The increasing interest in oxidative ageing has highlighted the need for a thorough understanding of the oxidation mechanisms at molecular level. This paper offers some insight in the validity of the proposed...book chapter 2021
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Vink, Jurriaan (author)The concept of Extended Producer Responsibility (EPR) is often connected to the Circular Economy (CE). According to policy plans, EPR would stimulate the transition to a CE. This thesis studies the role of EPR in the transition to a CE from an institutional perspective. It utilises a qualitative research approach, combining a literature review...master thesis 2020
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Tikhonova, Tamara V. (author), Sorokin, Dimitry Y. (author), Hagen, W.R. (author), Khrenova, Maria G. (author), Muyzer, Gerard (author), Rakitina, Tatiana V. (author), Shabalin, Ivan G. (author), Trofimov, Anton A. (author), Tsallagov, Stanislav I. (author), Popov, Vladimir O. (author)Biocatalytic copper centers are generally involved in the activation and reduction of dioxygen, with only few exceptions known. Here we report the discovery and characterization of a previously undescribed copper center that forms the active site of a copper-containing enzyme thiocyanate dehydrogenase (suggested EC 1.8.2.7) that was purified...journal article 2020
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Montes, Carlos (author), Berardi, Luigi (author), Kapelan, Z. (author), Saldarriaga, Juan (author)Sediment transport in sewer systems is an important issue of interest to engineering practice. Several models have been developed in the past to predict a threshold velocity or shear stress resulting in self-cleansing flow conditions in a sewer pipe. These models, however, could still be improved. This paper develops three new self-cleansing...journal article 2020
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Mahor, D. (author), Puschmann, J. (author), van den Haak, Menno (author), Kooij, Pepijn J. (author), van den Ouden, David L.J. (author), Strampraad, M.J.F. (author), Srour, B. (author), Hagedoorn, P.L. (author)Abstract: Chlorite dismutase is a unique heme enzyme that catalyzes the conversion of chlorite to chloride and molecular oxygen. The enzyme is highly specific for chlorite but has been known to bind several anionic and neutral ligands to the heme iron. In a pH study, the enzyme changed color from red to green in acetate buffer pH 5.0. The...journal article 2020
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Pipintakos, Georgios (author), Vincent Ching, H. Y. (author), Soenen, Hilde (author), Sjövall, Peter (author), Mühlich, Uwe (author), Van Doorslaer, Sabine (author), Varveri, Aikaterini (author), Van den bergh, Wim (author), Lu, Xiaohu (author)Oxidative ageing in bituminous materials is considered one of the most important factors for distress types in road applications. This paper aims to offer insights into the validity of commonly held beliefs regarding the oxidation phases of ageing in bitumen, the fast- and the slow-rate phase, and explore the main oxidation products formed...journal article 2020
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Kotuniak, Radosław (author), Strampraad, M.J.F. (author), Bossak-Ahmad, Karolina (author), Wawrzyniak, Urszula E. (author), Ufnalska, Iwona (author), Hagedoorn, P.L. (author), Bal, Wojciech (author)The amino-terminal copper and nickel/N-terminal site (ATCUN/NTS) present in proteins and bioactive peptides exhibits high affinity towards Cu<sup>II</sup> ions and have been implicated in human copper physiology. Little is known, however, about the rate and exact mechanism of formation of such complexes. We used the stopped-flow and...journal article 2020
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Hagen, W.R. (author)From the very first discovery of biological iron–sulfur clusters with EPR, the spectroscopy has been used to study not only purified proteins but also complex systems such as respiratory complexes, membrane particles and, later, whole cells. In recent times, the emphasis of iron–sulfur biochemistry has moved from characterization of...journal article 2018
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Molenaar, L.S. (author)We explore the foundations of quantum mechanics to see how the mathematics of QM was built. After that, we see what the EPR paradox is, why it was posed as a paradox and how it was solved.bachelor thesis 2014
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Honarmand Ebrahimi, K. (author)Storage of Fe(III) is a common mechanism by which the cellular machinery controls the availability of Fe(II) and Fe(III) for biosynthesis of iron-containing cofactors of enzymes which are involved in several essential biological processes, including oxidative phosphorylation. The conserved 24-meric iron-storage protein ferritin has been...doctoral thesis 2013
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Jansen, D.R. (author)It has become standard practice in the development of radiopharmaceuticals to evaluate/assess the efficacy of prospective therapeutic or diagnostic agents by animal models, which generally calls for subjecting a substantial number of animals to intensive test and retest measurements for obtaining representative and conclusive results/data. This...doctoral thesis 2010
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- De Val, N. (author), Hagen, W.R. (author), Crichton, R.R. (author) journal article 2007