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Large Eddy Simulation of environmental impacts on mass transport in laboratory-scale vertical farm
No full textThe impact of environmental factors on airflow and mass transport within a laboratory-scale vertical farm is investigated using Computational Fluid Dynamics. Large Eddy Simulation models complex airflow behaviour, while solving enthalpy and mass transport equations yields temperature, humidity, and CO2 concentration. The Eulerian-Lagrangian approach simulates the free-fall of water droplets in the dehumidifier-cooling system. Humidity and CO2 consumption/production by plants and utilities are modelled as volumetric sources/sinks. An experimental campaign is conducted to measure temperature, relative humidity, and CO2 above cultivation beds, validating the numerical setup with mean absolute errors of 0.8%, 2.2%, and 3.9%, respectively. Analysing the airflow shows that the free fall of droplets is the dominant mechanism driving airflow characteristics. We investigate the effects of wall confinement, number of lamps, and location of lamps on the mass transport. Curtains were used to divide each cultivation bed into three regions to assess the wall confinement effect. Results show the overall adverse effect of curtains on mass transport. In more detail, mass transport is enhanced when the curtains and streamlines are aligned parallel, whereas it is reduced when they are perpendicular. Increasing the number of operative lamps improves the uniformity of mass distribution on the upper cultivation beds due to a stronger positive buoyancy. Positioning lamp-induced buoyant flow within the droplet’s lateral momentum injection zone further enhances vertical mass transport. These findings highlight the impact of environmental factors on mass transport, offering insights for more efficient designs of indoor vertical farms.</p
Production of nitroaryl secondary metabolites by wood-decaying fungi of<i> Phlebia</i> spp.
No full textFilamentous fungi produce secondary metabolites with multiple biochemical activities. For wood-decaying fungi of Basidiomycota, some of these compounds may act as redox-active mediators involved in biodegradation of lignocelluloses and biopolymers. Our aim was to identify natural aromatic compounds produced by white rot fungi of the genus Phlebia (Meruliaceae, Polyporales, Agaricomycetes), which comprises efficient decomposers of wood, wastes, and xenobiotics. Naturally produced aryl compounds were obtained by cultivating the fungi on a defined low-nitrogen liquid medium with glucose as carbon source. Culture supernatants were extracted and analyzed with UPLC-MS (ultra-performance liquid chromatography–mass spectrometry) and NMR (nuclear magnetic resonance). Enzyme assays, cultivation with 15N isotope–labeled nitrogen supplement, and aryl compound–feeding experiments were performed to assess biosynthesis mechanisms. Together with the well-known secondary metabolite veratryl alcohol and its enzymatic oxidation product veratraldehyde, we identified two nitroaryl derivatives, 6-nitroveratryl alcohol and 4-nitroveratrole, accumulating in culture supernatants of Phlebia spp. Cultivation of P. radiata isolate 2776 with NH4NO3 caused higher product yield of the nitroaryl compounds than 15NH4Cl supplementation, suggesting a role of nitrate ions in formation of nitroaryl products. With 15N-labeled supplementation, however, incorporation of nitrogen also from ammonium ions was observed. Although lignin peroxidase (LiP) enzyme activities correlated with appearance of nitroaryl compounds, their formation from veratryl alcohol by LiP was not accomplished in vitro in reaction mixtures with extracellular supernatants. In compound-feeding experiments, additional glycosylated derivative of 6-nitroveratryl alcohol was detected in P. radiata cultures, and nitroguaiacol was formed from nitroveratrole. These results indicate multiple pathways including both intra- and extracellular metabolism in biosynthesis and bioconversion of monoaromatic aryl compounds and their derivatives in fungi of Phlebia
WeTRaC: Scalable EV charging demand forecasting for heavy-duty fleets
No full textThe rapid expansion of electric vehicles (EVs) in response to stricter emissions targets presents formidable challenges for power systems, particularly in scaling EV charging infrastructure to meet growing demands from heavy-duty fleets. Such demands are shaped by complex spatio-temporal interdependencies, such as weather conditions, traffic density, routes, and charging infrastructure, leading to imprecise charging demand predictions by the existing models that do not fully address all factors. This study introduces the Weather Traffic Routes and Chargers (WeTRaC), a predictive framework that unifies graph neural networks (GNNs) with physics-based vehicle simulations and open global data to produce high-precision forecasts of heavy-duty (i.e., buses and trucks) EV charging needs. Forecasts are generated at the vehicle level along routes and then aggregated to fleet- or corridor-level demand using probabilistic priors over vehicle attributes. We validate its performance through large-scale simulations (including ten international virtual corridor case studies) and real-world truck data from Finland, revealing a 500-fold computational speedup over conventional physics-based approaches at only a marginal (4%) accuracy trade-off. By identifying peak periods and locations of corridor demand for specified fleets, WeTRaC can effectively mitigate grid overload and accelerate the transition toward zero-emission transport
Exploring reference standards for the measurement of respiratory rate in children under 5 years of age:a scoping review
No full textBackground Respiratory rate is an important part of assessing the clinical state of children, and various methods exist to measure it. However, there is a lack of a universally accepted reference standard to validate the performance of these methods. Aim To identify different reference standards that have been used to evaluate respiratory rate measurement methods in children under 5 years of age and describe their perceived strengths and limitations. Methods MEDLINE and Web of Science were searched for studies in English. Studies of children under 5 years of age, published between 2013 and 2024, in which a method for measuring respiratory rate was compared against a reference standard, were included. Deductive content analysis was used to map perceived strengths and limitations of each standard, and a forest plot analysis was used to compare agreement between the reference standard and the index tests. Results From 992 retrieved studies, 56 were included. The most common reference standard was impedance pneumography (22/56), primarily used in high-income settings, followed by manual counting (19/56), mostly employed in low- and middle-income settings, and capnography (9/56). Child age, clinical condition, setting, training of personnel and the ease of implementation were all important factors in which the reference standard was used and how it performed. Conclusion Three different reference standards were used for most studies; however, their relative performance to each other is unclear. There is a need for research that directly compares the performance of these reference standards across different age strata and settings in order to confidently recommend a reference standard for respiratory rate measurement methods.</p
An integrated approach to structure, texture and nutritional quality in high-moisture extruded meat analogues from faba protein concentrate and single-cell proteins
No full textThis study evaluated meat analogues using high-moisture extrusion (HME) using faba protein concentrate (FPC) alone (Control) and blends with single-cell proteins (SCPs): microalgae Chlorella vulgaris (SCP1) and bacteria Xanthobacter spp. (SCP2). Three blends were formulated via linear programming based on the beneficial nutrients content in meat (beef, pork and chicken): Blend1 (60% FPC + 40% SCP1), Blend2 (22.5% FPC + 77.5% SCP2), and Blend3 (13.5% FPC + 11% SCP1 + 75.5% SCP2). Composition, texture, phytic acid and in vitro digestibility analyses assessed protein quality and mineral bioaccessibility. Samples were oven cooked before assays to simulate typical consumption. Cooking caused minor structural changes, without significantly affecting protein denaturation or phytic acid levels, as extrusion was the dominant thermal process. Protein digestibility was high (close to 100%) across all samples and generally unaffected by cooking. SCP inclusion significantly improved amino acid profiles, with Blend1 and Blend2 classified as excellent sources and Control and Blend3 as good sources of essential amino acids. Minerals such as manganese and potassium showed enhanced bioaccessibility linked to reduced phytic acid levels due to SCP incorporation and extrusion. Compared to average meat and dietary reference values, extruded blends demonstrated promising nutritional equivalency, supporting their potential as sustainable, nutrient-dense meat analogues. This study highlights the benefit of combining alternative protein blends with high-impact extrusion to enhance meat substitute nutritional quality
Trip chain characteristics and situational factors influencing private car mode choices – A survey study in two Finnish urban areas
Full text linkHuman mobility is often characterized by trip chains with multiple destinations. However, the reasons behind mode choices have been mostly studied in single-purpose travel contexts. To address this gap, we examine how trip chain length, complexity (number of trip legs), and purposes are linked to situational factors influencing the decision to use a private car (i.e., context-dependent considerations that affect travel decisions, such as the need to save time, avoid bad weather, or be able to relax). Data was collected through a survey where participants described a recent private car trip chain, including items about trip purposes, the number of trips and trip legs, trip length, and the importance of various situational factors on mode choice decision. The survey was conducted in two major urban areas in Finland, yielding 731 valid responses. The results of a regression analysis show that all examined trip chain characteristics impact on the prevalence of different situational factors. Leisure being a trip purpose was associated with non-utilitarian factors influencing car use, and errands and commuting with both utilitarian and non-utilitarian factors. Trips involving errands appeared more habitual than trips for other purposes. Furthermore, complexity was not only associated with utilitarian factors, but also non-utilitarian. The findings suggest that trip chain complexity and purposes should be considered by practitioners and policymakers in sustainable mobility campaigns, passenger information systems that account for trip chain characteristics should be developed, and targeted interventions to reduce habitual car use, especially for errands, should be created
Investigating tritium retention in tungsten coated plasma facing components from the divertor region of the Joint European Torus (JET) after ITER like-wall campaigns
No full textTritium retention is a critical aspect of plasma-facing wall component performance in fusion reactors as well as reactor safety due to radiological risks it may pose. It is also of importance in the case of tungsten, including tungsten composites, which are selected as first wall and divertor material at devices such as ITER due to its high melting point and mechanical strength. This study aims to investigate surface characteristics, tritium retention behaviour and effect of baking on tungsten composite plasma-facing wall components from Joint European Torus (JET) divertor region and contribute to the understanding of tritium trapping within them. Three ITER-like wall (ILW) experimental campaigns involved exposing tungsten-molybdenum coated carbon fibre composite (CFC) samples to deuterium-deuterium (D-D) plasma discharges at various operating conditions, including different plasma densities, temperatures, and exposure times. The plasma-facing surfaces were characterized using scanning electron microscopy (SEM) in combination with energy-dispersive x-ray spectroscopy (EDX) and tritium retention was assessed using thermal desorption spectroscopy (TDS) and full combustion. Baking cycle was simulated by keeping the sample at 350℃ for 100 h, followed by TDS and full combustion. Results indicate tritium retention varying from 2 to 120∙1012 T atoms/plasma facing surface cm2. A deposition layer was found to be present for most samples analysed in this study ranging from 0 to 58 µm in thickness. For Tile 0 an increase in tritium retention was observed by the increase in the thickness of the deposition layer, whilst for Tile 1 deposition was not found to be the main source of retention. Tritium desorption temperatures were found to be higher than that proposed for baking at ITER − for Tile 0 tritium desorption peaks at about 540-640℃, while for tile 1 it is generally lower, but with a larger deviation ranging from 350 up to 570℃.</p
OpenTextile-NIR: Near-infrared hyperspectral imaging and photography dataset for optical identification of textiles
No full textSee description at dataset page in Zenodo: https://zenodo.org/records/1826917
Enabling cryogenic technologies for superconducting quantum devices
No full textLow-temperature refrigerators cool systems down to cryogenic temperatures near absolute zero, where thermal noise and decoherence are suppressed. This allows quantum phases, such as superconductivity, to emerge in certain materials and enables the harnessing of individual quantum states for scientific and high-performance applications. However, the refrigerators used for these purposes are large and rely on cryoliquids, such as scarce and expensive 3He, which can be a limiting factor depending on the technological application. To enable more scalable, costeffective cryogenic platforms, new refrigeration technologies must be developed. To this end, chip-scale coolers based on superconducting tunnel junctions have been envisioned to provide a fully solid-state alternative. Proof-of-principle operation of these coolers has been demonstrated at temperatures below 1.5 K, but to link them with commercially available 4He pulse tube cryocoolers, stage operating above 2.0 K is required. Additionally, thermally isolating and electrically conducting methods are needed to cascade coolers operating at different temperature ranges. In this thesis, the fundamental components of a multi-stage chip-scale cooler operating at temperatures compatible with 4He pulse tube cryocoolers are developed. A superconducting flipchip assembly fabricated with In-bumps was characterized in the sub-kelvin temperature range, and the inter-chip thermal resistance was found to be suitable for chip-scale cooling applications. A through-chip signal routing method utilizing ALD TiN-based TSVs was developed, and the demonstrated critical temperature of 2.0 K enables dissipationless DC transport for multi-chip assemblies, such as cascaded coolers. Additionally, ALD MoCx was shown to exhibit a superconducting transition temperature up to 4.4 K and high conformality, showing promise as a TSV-compatible material. The key achievement of electronic cooling of Al thin film from a bath temperature of 2.4 K down to 1.6 K was demonstrated using Nb-based superconducting tunnel junctions, probed by an onchip junction thermometer. Thermal model calculations highlighted the emergence of superconductivity in the Al beneath the cooler junctions, persisting up to a bath temperature of 2.4 K: one kelvin higher than the nominal critical temperature of the Al thin film. The single-stage cooler operating above 2.0 K enables solid-state on-chip cooling from 4He pulse-tube compatible temperature without the use of magnetic fields. Additionally, Al- and V-based tunnel junctions were fabricated at the wafer scale using degenerately doped Si as the normal electrode. The junctions exhibited suitable low-temperature electrical characteristics for cooling applications. From superconducting interconnects to tunnel-junction components supporting high cooling power density above 1 K, the achievements presented in this thesis enable modular design of chip-scale cascade coolers. This technology is envisioned to support the scaling of several superconducting quantum devices from proof-of-principle to multi-component systems beyond experimental lab environments