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Cyanobacteria play a crucial role in global carbon and nitrogen cycles through photosynthesis, making them valuable subjects for understanding the factors influencing their light utilization efficiency. Photosynthetic microorganisms offer a promising avenue for sustainable energy conversion in the field of photovoltaics. It was demonstrated before that application of an external electric field to the microbial biofilm or cell improves electron transfer kinetics and, consequently, efficiency of power generation. We have integrated live cyanobacterial cultures into photovoltaic devices by embedding Limnospira indica PCC 8005 cyanobacteria in agar and PEDOT:PSS matrices on the surface of boron-doped diamond electrodes. We have subjected them to varying external polarizations while simultaneously measuring current response and photosynthetic performance. For the latter, we employed Pulse-Amplitude-Modulation (PAM) fluorometry as a non-invasive and real-time monitoring tool. Our study demonstrates an improved light utilization efficiency for L. indica PCC 8005 when immobilized in a conductive matrix, particularly so for low-intensity light. Simultaneously, the impact of electrical polarization as an environmental factor influencing the photosynthetic apparatus diminishes as matrix conductivity increases. This results in only a slight decrease in light utilization efficiency for the illuminated sample compared to the dark-adapted state., (© 2024. The Author(s).)

We present the change of light absorption of cyanobacteria in response to externally applied electrical polarization. Specifically, we studied the relation between electrical polarization and changes in light absorbance for a biophotoelectrode assembly comprising boron-doped diamond as semiconducting electrode and live Limnospira indica PCC 8005 trichomes embedded in either polysaccharide (agar) or conductive conjugated polymer (PEDOT-PSS) matrices. Our study involves the monitoring of cyanobacterial absorbance and the measurement of photocurrents at varying wavelengths of illumination for switched electric fields, i.e., using the bioelectrode either as an anode or as cathode. We observed changes in the absorbance characteristics, indicating a direct causal relationship between electrical polarization and absorbing properties of L. indica . Our finding opens up a potential avenue for optimization of the performance of biophotovoltaic devices through controlled polarization. Furthermore, our results provide fundamental insights into the wavelength-dependent behavior of a bio photovoltaic system using live cyanobacteria., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Diamond electrochemistry is primarily influenced by quantities of sp 3 -carbon, surface terminations, and crystalline structure. In this work, a new dimension is introduced by investigating the effect of using substrate-interlayers for diamond growth. Boron and nitrogen co-doped nanocrystalline diamond (BNDD) films are grown on Si substrate without and with Ti and Ta as interlayers, named BNDD/Si, BNDD/Ti/Si, and BNDD/Ta/Ti/Si, respectively. After detailed characterization using microscopies, spectroscopies, electrochemical techniques, and density functional theory simulations, the relationship of composition, interfacial structure, charge transport, and electrochemical properties of the interface between diamond and metal is investigated. The BNDD/Ta/Ti/Si electrodes exhibit faster electron transfer processes than the other two diamond electrodes. The interlayer thus determines the intrinsic activity and reaction kinetics. The reduction in their barrier widths can be attributed to the formation of TaC, which facilitates carrier tunneling, and simultaneously increases the concentration of electrically active defects. As a case study, the BNDD/Ta/Ti/Si electrode is further employed to assemble a redox-electrolyte-based supercapacitor device with enhanced performance. In summary, the study not only sheds light on the intricate relationship between interlayer composition, charge transfer, and electrochemical performance but also demonstrates the potential of tailored interlayer design to unlock new capabilities in diamond-based electrochemical devices., (© 2024 The Author(s). Small Methods published by Wiley‐VCH GmbH.)

Background: Coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) is a frequent superinfection in critically ill patients with COVID-19 and is associated with increased mortality rates. The increasing proportion of severely immunocompromised patients with COVID-19 who require mechanical ventilation warrants research into the incidence and impact of CAPA during the vaccination era., Methods: We performed a retrospective, monocentric, observational study. We collected data from adult patients with severe COVID-19 requiring mechanical ventilation who were admitted to the intensive care unit (ICU) of University Hospitals Leuven, a tertiary referral center, between 1 March 2020 and 14 November 2022. Probable or proven CAPA was diagnosed according to the 2020 European Confederation for Medical Mycology/International Society for Human and Animal Mycology (ECMM/ISHAM) criteria., Results: We included 335 patients. Bronchoalveolar lavage sampling was performed in 300 (90%), and CAPA was diagnosed in 112 (33%). The incidence of CAPA was 62% (50 of 81 patients) in European Organisation for Research and Treatment of Cancer (EORTC)/Mycosis Study Group Education and Research Consortium (MSGERC) host factor-positive patients, compared with 24% (62 of 254) in host factor-negative patients. The incidence of CAPA was significantly higher in the vaccination era, increasing from 24% (57 of 241) in patients admitted to the ICU before October 2021 to 59% (55 of 94) in those admitted since then. Both EORTC/MSGERC host factors and ICU admission in the vaccination era were independently associated with CAPA development. CAPA remained an independent risk factor associated with mortality risk during the vaccination era., Conclusions: The presence of EORTC/MSGERC host factors for invasive mold disease is associated with increased CAPA incidence and worse outcome parameters, and it is the main driver for the significantly higher incidence of CAPA in the vaccination era. Our findings warrant investigation of antifungal prophylaxis in critically ill patients with COVID-19., Competing Interests: Potential conflicts of interest. S. F. and L. V. report PhD funding from the Research Foundation–Flanders (FWO; grants 11M6922N and 11E9819N). S. F. reports receipt of travel grants from Pfizer and Gilead and speaker fees from Healthbook. K. L. received consultancy fees from MRM Health, Merck Sharp and Dohme (MSD), and Mundipharma, speaker fees and travel support from Pfizer and Gilead, and a service fee from Thermo Fisher Scientific and TECOmedical and participated on an advisory board for MSD. Y. D. received travel grants from Pfizer (travel/congress attendance support) and declares participation on advisory boards for Pfizer and MSD. G. H. and R. V. are senior clinical research fellows of FWO. G. H. received travel fees from Eurosets for the 2023 Extracorporeal Life Support Organization meeting. M. H. received grants from Astellas, Gilead, MSD, Pfizer, Euroimmun, IMMY, Mundipharma, F2G, Pulmocide, and Scynexis and research funding from Gilead Sciences, Astellas, Mundipharma, Euroimmun, MSD, Pulmocide, IMMY, Scynexis, F2G, and Pfizer. J. M. received grants from Bio-Rad, Gilead Sciences, MSD, F2G, Mundipharma, and Pfizer; personal fees and nonfinancial support from Astellas, Basilea, Gilead Sciences, MSD, F2G, Mundipharma, and Pfizer; and personal fees from Bio-Rad. M. P. received travel fees from Pfizer (March 2023; registration for the 2023 International Symposium on Intensive Care & Emergency Medicine (ISICEM) in Brussels, Belgium). I. S. received funding from the Clinical Research Fund, University Hospitals Leuven, investigator-initiated grants from Pfizer, and speaker and travel fees from Pfizer, Gilead, and MSD, and reports participation on an advisory board for Pfizer and Gilead, and receipt of study drugs from MSD. L. V. received support for public doctoral defense from Pfizer and travel fees for conference attendance from Gilead Sciences and Pfizer and reports a PhD fellowship (grant 11E9819N) from FWO. R. V. reports an FWO fellowship and grant (grant G060322N). E. V. W. received travel fees from Gilead (for travel, hotel, and registration). J. W. received investigator-initiated grants from Pfizer, Gilead, and MSD and speaker and travel fees from Pfizer, Gilead, and MSD, and declares participation on advisory boards of Pfizer and Gilead and receipt of study drugs from MSD. J. W. also reports funding from the European Union's Horizon 2020 research and innovation program (grant 847507 HDM-FUN) and FWO project funding (grant G053121N). All other authors report no potential conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)

This special issue discusses current progress in the utilization of defect centres in diamond as spin-photon interfaces for quantum applications. This issue is based on the discussions of the Theo Murphy meeting 'Diamond for quantum applications' which covered the recent progress of diamond growth and engineering for the creation and optimization of colour centres, toward the integration of diamond-based qubits in quantum systems. This article is part of the Theo Murphy meeting issue 'Diamond for quantum applications'.

Surface treatment is critical for homogeneous coating over a large area and high-resolution patterning of nanodiamond (ND) particles. To optimize the interaction between the surface of a substrate and the colloid of ND particles, it is essential to remove hydrocarbon contamination by surface treatment and to increase the surface energy of the substrate, hence improving the diamond film homogeneity upon its deposition. However, the impact of substrate surface treatment on the properties of coatings and patterns is not fully understood. This study explores the impact of UV-ozone, O 2 plasma, and CF 4 plasma treatments on the wetting properties of the fused silica glass substrate surface. We identify the optimal time interval between the treatment and subsequent ND coating/patterning processes, which were conducted using inkjet printing and ultrasonic spray coating techniques. Our results showed that UV-ozone and O 2 plasma resulted in hydrophilic surfaces, while CF 4 plasma treatment resulted in hydrophobic surfaces. We demonstrate the use of CF 4 plasma treatment before inkjet printing to generate high-resolution patterns with dots as small as 30 μm in diameter. Ultrasonic spray coating showed homogeneous coatings after using UV-ozone and O 2 plasma treatment. The findings of this study provide valuable insights into the hydrocarbon airborne contamination on cleaned surfaces over time even in clean-room environments and have a notable impact on the performance of liquid coatings and patterns. We highlight the importance of timing between the surface treatment and printing in achieving high resolution or homogeneity.