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Supporting mental health self-care discovery through a chatbot

Moilanen, Joonas (author), van Berkel, Niels (author), Visuri, Aku (author), Gadiraju, Ujwal (author), van der Maden, W.L.A. (author), Hosio, Simo (author)

Good mental health is imperative for one’s wellbeing. While clinical mental disorder treatments exist, self-care is an essential aspect of mental health. This paper explores the use and perceived trust of conversational agents, chatbots, in the context of crowdsourced self-care through a between-subjects study (N = 80). One group used a...

journal article 2023

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Light-Driven NADPH Cofactor Recycling by Photosystem I for Biocatalytic Reactions

Medipally, Hitesh (author), Guarneri, Alice (author), Pospisil, Lars (author), Franssen, Maurice C.R. (author), van Berkel, Willem J.H. (author), Paul, C.E. (author), Nowaczyk, Marc M. (author)

Biocatalytic asymmetric reduction of C=C and C=O bonds is highly attractive to produce valuable (chiral) chemicals for the fine and pharmaceutical industry, yet occurs at the expense of reduced nicotinamide adenine dinucleotide coenzyme NADPH that requires recycling. Established methods each have their challenges. Here we developed a light...

journal article 2023

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An f/0.27 High-Gain Lens Antenna for Ultrasmall Platforms at THz Frequencies

van Berkel, S.L. (author), Alonso Del Pino, M. (author), Jung-Kubiak, Cecile (author), Chattopadhyay, Goutam (author)

The development of a low focal number and low-mass lens antenna is presented that enables terahertz spectroscopy applications on ultracompact platforms. The antenna operates efficiently over a 20% fractional bandwidth, from 450 to 550 GHz, with a gain of 50 dBi at 500 GHz. The antenna consists of a hyperbolic silicon lens that is placed in a...

journal article 2023

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Chessboard Focal Plane Array for a CMOS-Integrated Terahertz Camera

Hoogelander, M. (author), van Berkel, S.L. (author), Malotaux, E.S. (author), Alonso Del Pino, M. (author), Cavallo, D. (author), Spirito, M. (author), Llombart, Nuria (author)

This article presents the development of a focal plane array (FPA) for terahertz imaging applications with a near diffraction-limited resolution achieved through a very tight sampling of the focal plane. The antenna array is integrated with direct detectors in a 22-nm CMOS technology and operates from 200 to 600 GHz. The tight sampling of the...

journal article 2023

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Exciting Enzymes: Current State and Future Perspective of Photobiocatalysis

Alphand, Véronique (author), van Berkel, Willem J.H. (author), Jurkaš, Valentina (author), Kara, Selin (author), Kourist, Robert (author), Kroutil, Wolfgang (author), Mascia, Francesco (author), Nowaczyk, Marc M. (author), Paul, C.E. (author)

The recent increase of interest in photocatalysis spread to biocatalysis and triggered a rush for the development of light-dependent enzyme-mediated or enzyme-coupled processes. After several years of intense research on photobiocatalysis, it is time to evaluate the state of the field in a structured manner. In this Perspective, we suggest to...

journal article 2023

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Lens Absorber Coupled MKIDs for Far Infrared Imaging Spectroscopy

Dabironezare, Shahab Oddin (author), van Berkel, Sven (author), Echternach, Pierre M. (author), Day, Peter K. (author), Bradford, Charles M. (author), Baselmans, J.J.A. (author)

Future generation of astronomical imaging spectrometers are targeting the far infrared wavelengths to close the THz astronomy gap. Similar to lens antenna coupled Microwave Kinetic Inductance Detectors (MKIDs), lens absorber coupled MKIDs are a candidate for highly sensitive large format detector arrays. However, the latter is more robust to...

conference paper 2023

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Diffraction-Limited Imaging Demonstration using a Silicon Integrated Array at Terahertz Frequencies

Hoogelander, M. (author), van Berkel, S.L. (author), Malotaux, E.S. (author), Alonso Del Pino, M. (author), Spirito, M. (author), Neto, A. (author), Cavallo, D. (author), Llombart, Nuria (author)

In this contribution we will present the diffraction-limited imaging capabilities of a focal plane array (FPA) of antenna-coupled direct-detectors at submillimeter wavelengths. The FPA prototype is a tightly sampled, 12-pixel array that was developed in a 22 nm CMOS technology and it covers a band from 200 GHz to 600 GHz. A quasi-optical (QO)...

conference paper 2022

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Efficient Waveguide Feeds for Low-Profile Submm-wave Lens Antennas

van Berkel, Sven (author), Alonso Del Pino, M. (author), Jung-Kubiak, Cecile (author), Chattopadhyay, Goutam (author)

A small volume and low-mass THz spectroscopy instrument, integrated in a CubeSat platform, enables an accessible and low-cost pathway to earth science. Low-profile lens antennas emerge as a suitable candidate to realize a high gain, 50 dB, over a wide bandwidth, from 450 GHz to 550 GHz. To achieve a high aperture efficiency with a large...

conference paper 2022

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Wideband Modeling of CMOS Schottky Barrier Diode Detectors for THz Radiometry

van Berkel, S.L. (author), Malotaux, E.S. (author), De Martino, C. (author), Spirito, M. (author), Cavallo, D. (author), Neto, A. (author), Llombart, Nuria (author)

A complete system modeling and characterization of a wideband differential terahertz (THz) direct detector, integrated in a commercial CMOS technology, is presented. The detector consists of a recently developed double leaky-slot lens antenna that operates from 200 to 600 GHz in combination with a differential Schottky barrier diode (SBD) direct...

journal article 2021

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Flavoprotein monooxygenases: Versatile biocatalysts

Paul, C.E. (author), Eggerichs, Daniel (author), Westphal, Adrie H. (author), Tischler, Dirk (author), van Berkel, Willem J.H. (author)

Flavoprotein monooxygenases (FPMOs) are single- or two-component enzymes that catalyze a diverse set of chemo-, regio- and enantioselective oxyfunctionalization reactions. In this review, we describe how FPMOs have evolved from model enzymes in mechanistic flavoprotein research to biotechnologically relevant catalysts that can be applied for...

review 2021

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The influence of the exclusion of central necrosis on [¹⁸F]FDG PET radiomic analysis

Noortman, Wyanne A. (author), Vriens, Dennis (author), Mooij, C.D.Y. (author), Slump, Cornelis H. (author), Aarntzen, Erik H. (author), van Berkel, Anouk (author), Timmers, Henri J.L.M. (author), Bussink, Johan (author), Meijer, Tineke W.H. (author), de Geus-Oei, Lioe Fee (author), van Velden, Floris H.P. (author)

Background: Central necrosis can be detected on [¹⁸F]FDG PET/CT as a region with little to no tracer uptake. Currently, there is no consensus regarding the inclusion of regions of central necrosis during volume of interest (VOI) delineation for radiomic analysis. The aim of this study was to assess how central necrosis affects...

journal article 2021

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On the Development of Wideband Direct Detection Focal Plane Arrays for THz Passive Imaging Applications

van Berkel, S.L. (author)

In the design of millimeter and sub-millimeter wave radiometric imaging systems a persistent goal is the increase in the speed of acquisition of the image while maintaining a high sensitivity. Typically, the highest sensitivity is achieved by cryogenically cooling the detectors, specifically in astronomical applications. However, for the purpose...

doctoral thesis 2020

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Flavoenzyme-mediated Regioselective Aromatic Hydroxylation with Coenzyme Biomimetics

Guarneri, A. (author), Westphal, Adrie H. (author), Leertouwer, C.J. (author), Lunsonga, Joy (author), Franssen, Maurice C.R. (author), Opperman, Diederik J. (author), Hollmann, F. (author), van Berkel, Willem J.H. (author), Paul, C.E. (author)

Regioselective aromatic hydroxylation is desirable for the production of valuable compounds. External flavin-containing monooxygenases activate and selectively incorporate an oxygen atom in phenolic compounds through flavin reduction by the nicotinamide adenine dinucleotide coenzyme, and subsequent reaction with molecular oxygen. This study...

journal article 2020

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Flavin-dependent N-hydroxylating enzymes: Distribution and application

Mügge, Carolin (author), Heine, Thomas (author), Baraibar, Alvaro Gomez (author), van Berkel, Willem J.H. (author), Paul, C.E. (author), Tischler, Dirk (author)

Amino groups derived from naturally abundant amino acids or (di)amines can be used as “shuttles” in nature for oxygen transfer to provide intermediates or products comprising N-O functional groups such as N-hydroxy, oxazine, isoxazolidine, nitro, nitrone, oxime, C-, S-, or N-nitroso, and azoxy units. To this end, molecular oxygen is activated...

review 2020

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An Ultra-Wideband Leaky Lens Antenna for Broadband Spectroscopic Imaging Applications

Hähnle, S.A. (author), Yurduseven, Ozan (author), van Berkel, S.L. (author), Llombart, Nuria (author), Bueno, Juan (author), Yates, Stephen J.C. (author), Murugesan, Vignesh (author), Thoen, David (author), Neto, A. (author), Baselmans, J.J.A. (author)

We present the design, fabrication, and characterization of a broadband leaky lens antenna for broadband, spectroscopic imaging applications. The antenna is designed for operation in the 300-900 GHz band. We integrate the antenna directly into an Al-NbTiN hybrid microwave kinetic inductance detector (MKID) to measure the beam pattern and...

journal article 2020

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High Resolution Passive THz Imaging Array with Polarization Reusage in 22nm CMOS

van Berkel, S.L. (author), Malotaux, E.S. (author), Spirito, M. (author), Cavallo, D. (author), Neto, A. (author), Llombart, Nuria (author)

A 12-pixel THz Focal Plane Array (FPA), integrated in Global Foundries 22nm CMOS technology, enabling high resolution passive THz imaging, is presented. The array efficiently couples blackbody radiation from 200 GHz to 600 GHz to Schottky Barrier Diodes (SBDs) in a differential topology. An antenna-detector co-design results in an average...

conference paper 2019

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Alternative coenzymes for biocatalysis

Guarneri, A. (author), van Berkel, Willem JH (author), Paul, C.E. (author)

Coenzymes are ubiquitous in Nature, assisting in enzyme-catalysed reactions. Several coenzymes, nicotinamides and flavins, have been known for close to a century, whereas variations of those organic molecules have more recently come to light. In general, the requirement of these coenzymes imposes certain constraints for in vitro enzyme use in...

review 2019

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Optical Performance of a Wideband 28nm CMOS Double Bow-Tie Slot Antenna for Imaging Applications

van Berkel, S.L. (author), Malotaux, E.S. (author), Cavallo, D. (author), Spirito, M. (author), Neto, A. (author), Llombart, Nuria (author)

The optical performance of a wideband double bowtie slot antenna, implemented in 28nm CMOS technology, is evaluated. The antenna serves as a verification antenna for an uncooled single-pixel radiometer operating from 200 GHz to 600 GHz. The performance is evaluated in terms of radiometric pattern that is derived from the measured radiation...

conference paper 2018

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Oxidoreductases on their way to industrial biotransformations

Martínez, Angel T. (author), Ruiz-Dueñas, Francisco J. (author), Camarero, Susana (author), Serrano, Ana (author), Linde, Dolores (author), Lund, Henrik (author), Vind, Jesper (author), Tovborg, Morten (author), Herold-Majumdar, Owik M. (author), Hofrichter, Martin (author), Liers, Christiane (author), Ullrich, René (author), Scheibner, Katrin (author), Sannia, Giovanni (author), Piscitelli, Alessandra (author), Pezzella, Cinzia (author), Sener, Mehmet E. (author), Kılıç, Sibel (author), van Berkel, Willem J.H. (author), Guallar, Victor (author), Lucas, Maria Fátima (author), Zuhse, Ralf (author), Ludwig, Roland (author), Hollmann, F. (author), Fernandez Fueyo, E. (author), Record, Eric (author), Faulds, Craig B. (author), Tortajada, Marta (author), Winckelmann, Ib (author), Rasmussen, Jo Anne (author), Gelo-Pujic, Mirjana (author), Gutiérrez, Ana (author), del Río, José C. (author), Rencoret, Jorge (author), Alcalde, Miguel (author)

Fungi produce heme-containing peroxidases and peroxygenases, flavin-containing oxidases and dehydrogenases, and different copper-containing oxidoreductases involved in the biodegradation of lignin and other recalcitrant compounds. Heme peroxidases comprise the classical ligninolytic peroxidases and the new dye-decolorizing peroxidases, while...

review 2017

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Old yellow enzyme-catalysed asymmetric hydrogenation: Linking Family Roots with Improved Catalysis

Scholtissek, Anika (author), Tischler, Dirk (author), Westphal, Adrie H. (author), van Berkel, Willem J.H. (author), Paul, C.E. (author)

Asymmetric hydrogenation of activated alkenes catalysed by ene-reductases from the old yellow enzyme family (OYEs) leading to chiral products is of potential interest for industrial processes. OYEs’ dependency on the pyridine nucleotide coenzyme can be circumvented through established artificial hydride donors such as nicotinamide coenzyme...

journal article 2017