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PublicationPositive Energy Districts. The 10 Replicated Solutions in Maia, Reykjavik, Kifissia, Kladno and Lviv( 2023-12-20)Cities have an undoubted significant role in climate change mitigation. Several cities across the globe have made commitments to sustainability transitions through green strategies. In the recent past, Europe has witnessed a surge in the development of smart cities and advancement towards creating more sustainable cities. At the moment, the concept of Positive Energy Districts (PEDs) further encourages districts and cities to change their business-as-usual ways to be more carbon neutral. This paper looks at the five cities of Maia, Reykjavik, Kifissia, Kladno, and Lviv that are a part of an ongoing Horizon 2020 project. The purpose of the paper was to understand the steps the cities have taken to select the 10 solutions for replication. The information was collected through discussions, interviews and implementation plans developed by each city. It must be highlighted that each city’s circumstances differ in terms of political support, finances, technical expertise, and stakeholders’ interest, and this applies to all world cities when discussing the implementation of new efficient solutions. Cities across Europe and beyond may find themselves in a similar situation, and therefore, this paper also provides a story of the five Fellow Cities as they transition towards PEDs.
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PublicationCharacterization of human oxidoreductases involved in aldehyde odorant metabolism( 2023-12)Oxidoreductases are major enzymes of xenobiotic metabolism. Consequently, they are essential in the chemoprotection of the human body. Many xenobiotic metabolism enzymes have been shown to be involved in chemosensory tissue protection. Among them, some were additionally shown to be involved in chemosensory perception, acting in signal termination as well as in the generation of metabolites that change the activation pattern of chemosensory receptors. Oxidoreductases, especially aldehyde dehydrogenases and aldo-keto reductases, are the first barrier against aldehyde compounds, which include numerous odorants. Using a mass spectrometry approach, we characterized the most highly expressed members of these families in the human nasal mucus sampled in the olfactory vicinity. Their expression was also demonstrated using immunohistochemistry in human epitheliums sampled in the olfactory vicinity. Recombinant enzymes corresponding to three highly expressed human oxidoreductases (ALDH1A1, ALDH3A1, AKR1B10) were used to demonstrate the high enzymatic activity of these enzymes toward aldehyde odorants. The structure-function relationship set based on the enzymatic parameters characterization of a series of aldehyde odorant compounds was supported by the X-ray structure resolution of human ALDH3A1 in complex with octanal.
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PublicationFilm processing of Li6PS5Cl electrolyte using different binders and their combinations( 2023-08)The development of solid electrolytes has made significant progress in the last decade. Among the most promising materials, sulfide-based electrolytes show high ionic conductivities and low densities, and their precursors are abundant. For industrially relevant battery cells, sulfide electrolytes need to be processed to form thin electrolyte sheets that are either directly applied to the electrodes as coatings or prepared as stand-alone films. Thus, processing of sulfide electrolyte powders has recently drawn much attention as it seems to be one of the major challenges in realizing sulfide-based all-solid-state batteries. In this work, six different binders (NBR, HNBR, PIB, PBMA, SBS, SEBS) were selected for preparation of electrolyte films using Li6PS5Cl as a sulfidic model compound. The influence of the binders on the electrochemical performance as well as on the mechanical properties of the resulting films was investigated. In addition, binder blends were explored as a vial approach to optimize the properties of the electrolyte films. Special focus was put on elucidating the relation between the physico-chemical properties of the binder materials and the resulting electrochemical and mechanical properties of the electrolyte films.
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PublicationEfectroH2O: Development and evaluation of a novel treatment technology for high-brine industrial wastewater( 2023-07-20)Textile production is one of the main sources of freshwater consumption by industries worldwide. In addition, according to the world bank, 20 % of the wastewater generated globally is caused by textile wet-processing. Textile wet-processing includes the processes in textile production where garments are dyed or given the final functions like water-repellency. Several thousand chemicals were used in this process, some of which are highly toxic. Discharging untreated or insufficiently treated wastewater in water bodies results in high pollution levels, severely impacting the environment and human health. Especially in textile-producing countries like India, environmental pollution and water consumption from textile wet-processing have severe impacts. Next to the high volume of chemicals used in textile production, the high salt concentration in textile wastewater also poses a challenge and is critical for freshwater systems. Moreover, textile wastewater is one of the most difficult to treat wastewater. Currently, used treatment technologies do not meet the requirements to treat textile wastewater. Therefore, the further development of efficient treatment technologies for textile wastewater is critically important. Hence, in the interdisciplinary project, effect-based monitoring demonstrates the efficiency of electrically-driven water treatment processes to remove salts and micropollutants from process water (EfectroH2O), a low-energy Zero Liquid Discharge (ZLD) textile wastewater treatment technology is being developed consisting of a combination of capacitive deionization (CDI) and advanced oxidation processes (AOP). In addition to treatment technology development, methods for evaluating the efficiency of treatment technologies also need to be improved. Currently, mainly physicochemical parameters such as pH, biochemical oxygen demand (BOD) and chemical oxygen demand (COD) are tested worldwide to check water quality. However, these methods are insufficient to make a statement about the toxic potential of such complex mixtures as textile wastewater. Therefore, also next to chemical analyses, effect-based methods (EBM) are used to verify the treated wastewater.
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PublicationDegradation mechanism of the wood-cell wall surface in a cement environment measured by atomic force microscopy( 2023-07-01)Lignocellulosic materials in an alkaline cement environment can be subjected to degradation that always starts from the surface. Atomic force microscopy has been used to establish the changes of surface properties of wood-cell walls. We measured the topographies and adhesion force curves of wood-cell wall surfaces before and after treatments in cement alkaline solutions ranging from 0.5 to 1,104 h at 20°C and 50°C and compared them with untreated controls. We studied the degradation of the cell wall surfaces chemically (dissolution of extractives and degradation of the hemicelluloses-lignin matrix), structurally (changes in surface modulus and deformation), and topographically (looking at the change in cell wall surface). The adhesion forces and jump-off force ratios shifted along two sigmoidal curves and showed a transition phase based on the treatment times. In this article, we analyzed and explained how the cutting and surface heterogeneity affects the atomic force microscopy measurements, and how the temperature rise due to the cement hydration heat could accelerate the surface degradation.
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PublicationMulti-scale investigation of morphological, physical and tensile properties of flax single fiber, yarn and unidirectional fabric( 2023-06-15)In this study, the morphological, physical, and tensile properties of flax were experimentally investigated at three different scales (single fiber, yarn and unidirectional fabric). The cross-sectional area was determined directly using microscopic image and indirectly via linear density with gravimetric and vibroscopic methods. All specimens were tested in tension until failure. The results showed that measured properties and their variability were scale-dependent. The tensile strength and modulus of elasticity were gradually decreasing with the scale and the variabilities were decreasing when going from fibers to yarns and fabric. This difference in the properties should be considered for any multi-scale analysis of the flax reinforcement. The average failure strains of single fiber, yarn and fabric were 2% (±30%), 1.7% (±12%) and 1.7% (±2.8%), respectively. Due to the consistency of failure strain at different material scales, it can be recommended as design criterion. The results of this study can be used for better design and preparation of plant-based natural fiber reinforced polymer composites.
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PublicationEffective mechanochemical synthesis of sulfide solid electrolyte Li3PS4 in a high energy ball mill by process investigation( 2023-06)Mechanochemical syntheses have a high potential as environmentally friendly and scalable processes. However, especially in case of solid electrolytes, these syntheses are reported as very time consuming with process times up to several days. In this study, the sulfide solid electrolyte Li3PS4 was successfully synthesized in less than 5h after a systematic variation and subsequently optimization of the process parameters in a high energy ball mill. The synthesized electrolyte samples were characterized according to their composition, morphology, particle size distribution and ionic conductivity. Therefore, a better understanding of the process-structure-property relations and process efficiency was achieved. Thus, the results allow a correlation between the stressing conditions and kinetic rates. The stressing conditions are mainly affected by process parameters such as rotational speed, grinding media size and grinding media filling ratio. The kinetic of the mechanochemical process is highly dependent on the normal power input by head-on collisions, leading to a reduction of conversion time with increasing specific power input. The different sets of investigated process parameters also exhibit systematic effects on the crystallinity and particle size distribution of the solid electrolytes. As a result, a highly enhanced process with lowest specific energy demand was achieved by using the largest grinding media with highest rotational speeds at medium grinding media filling ratio.
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PublicationProof of concept of an accelerometer as a trigger for unilateral diaphragmatic pacing: a porcine model( 2023-05-31)Background: Unilateral diaphragmatic paralysis in patients with univentricular heart is a known complication after pediatric cardiac surgery. Because diaphragmatic excursion has a significant influence on perfusion of the pulmonary arteries and hemodynamics in these patients, unilateral loss of function leads to multiple complications. The current treatment of choice, diaphragmatic plication, does not lead to a full return of function. A unilateral diaphragmatic pacemaker has shown potential as a new treatment option. In this study, we investigated an accelerometer as a trigger for a unilateral diaphragm pacemaker (closed-loop system). Methods: Seven pigs (mean weight 20.7 ± 2.25 kg) each were implanted with a customized accelerometer on the right diaphragmatic dome. Accelerometer recordings (mV) of the diaphragmatic excursion of the right diaphragm were compared with findings using established methods (fluoroscopy [mm]; ultrasound, M-mode [cm]). For detection of the amplitude of diaphragmatic excursions, the diaphragm was stimulated with increasing amperage by a cuff electrode implanted around the right phrenic nerve. Results: Results with the different techniques for measuring diaphragmatic excursions showed correlations between accelerometer and fluoroscopy values (correlation coefficient 0.800, P < 0.001), accelerometer and ultrasound values (0.883, P < 0.001), and fluoroscopy and ultrasound values (0.816, P < 0.001). Conclusion: The accelerometer is a valid method for detecting diaphragmatic excursion and can be used as a trigger for a unilateral diaphragmatic pacemaker.
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PublicationRapid identification of in vitro cell toxicity using an electrochemical membrane screening platform( 2023-05-23)
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PublicationPotentials and Limits of Filter Technology for the Regulation of Hate Speech and Fake News( 2023-05-23)Illegal and (lawful, but) harmful content - most notably hate speech and fake news, but also violent videos, copyright infringement, or child pornography - is a crucial problem on digital platforms like Facebook, YouTube, TikTok and Twitter. The EU’s 2022 Digital Services Act aims at tackling this problem by introducing an updated horizontal framework for all categories of content and activities on intermediary services. This raises several questions. How far do - national and European - free speech guarantees go? If hate speech can be banned to protect the victims’ rights, how can the prohibition of fake news be justified? What is the remaining leeway of the platforms for private content moderation? Who is responsible for fighting and taking down illegal content? How can the victims of de-platforming, content takedowns or shadow banning claim their right to freedom of opinion? Finally, how will these legal responsibilities be enforced? These questions are addressed in the articles of the edited volume, proceeding from the 2022 Annual Conference of the Institute for Digital Law Trier (IRDT).
