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Public policies for the circular economy – examples of European policies and references for Brazil
No full textPhotonic contact thermometry based on 3 µm thick silicon cascaded ring resonators
No full textWe demonstrate a photonic temperature sensor based on three silicon cascaded ring resonators (CRRs) integrated on a 3 µm thick silicon-on-insulator (SOI) platform for contact thermometry. A CRR-based sensor achieves an expanded free spectral range (FSR) of 23 nm, enabling a broader operational temperature range compared with the FSR of 1 nm for the single ring resonator. The thick SOI platform offers several advantages, including low propagation loss (less than 0.1 dB cm-1), negligible polarization dependence (approaching zero birefringence) and high-power handling capability (greater than 10 mW) without any resonance shape deformation from two-photon absorption (TPA). Optical coupling was achieved through edge-coupled fibre packaging to the photonic chip. The sensor exhibits a temperature sensitivity of 85 pm K-1 with an uncertainty of 16.1 mK, measured over a temperature range from -20 to 90°C. This article is part of the Theo Murphy meeting issue 'The redefined kelvin: progress and prospects'.</p
Microbial metabolism in deep terrestrial subsurface communities - amino acids as biosignatures
Get PDFThe deep terrestrial subsurface (DTS) biosphere consists of a variety of distinct microbial taxa, mostly bacterial. The mechanisms by which microbes dynamically manage the uptake and concurrent utilization of nutrients within the DTS environments remain largely unexplored. Here, we examined the utilization patterns of amino acids and other polar metabolites in cultured DTS bacterial communities to investigate the adaptive responses and metabolic pathways employed under varying nutrient conditions to gain insight into how environmental shifts impact the metabolism of these communities. Previously, we found that changes in growth conditions affected the composition and size of the bacterial communities enriched from these oligotrophic, anoxic environments and induced changes in the production of primary and secondary metabolites. In the present study, metabolic fingerprinting was used to investigate the primary and secondary metabolite utilization and main metabolic pathways present in the enriched DTS bacterial consortium originating from the deep bedrock of the Fennoscandian Shield. We found that especially amino acids were predominantly degraded under different nutrient conditions. Notably, the degradation of phenylalanine and valine constituted a 'core' metabolic process that remained unaffected by variations in available nutrients within this community. Further, the most significant metabolic pathways employed were those connected to phenylalanine, cysteine and methionine.</p
Influence of environment and microbes on corrosion behavior of welded steels in the LILW repositories (MICWEST-project)
No full textUnderstanding the Gender Gap in the Acceptance of Automated Vehicles:International Mobility Study Across 17 Countries
No full textThe common assumption is that men are more likely to accept automated vehicles (AVs) than women. However, studies have produced mixed results regarding this gender gap. Additionally, there is limited understanding of how the gender gap in the intention to use AVs might vary between countries. This study aims to enhance the understanding of the gender gap in willingness to use AVs and how this gap might differ across various countries. To accomplish this, survey data from 18,631 respondents across 17 countries: Brazil, China, Finland, France, Germany, Hungary, India, Indonesia, Italy, Japan, Russia, Spain, South Africa, Sweden, Turkey, the UK, and the US, was analyzed. In this research, the gender gap in willingness to use AVs is defined as the difference in willingness to use AVs between men and women. The results indicate that gender differences in willingness to use AVs are not universal; some countries show opposing trends between men and women, while in others, the gender difference is not statistically significant. This study contributes to existing literature by examining the influence of gender and country on the willingness to use AVs. The findings have the potential to significantly impact policy development and transport planning by promoting gender inclusivity in future transport solutions, ensuring that all potential users can benefit from adopting AVs.</p
Attention-driven refinement network for continuity-preserving airway segmentation in class-imbalanced CT
No full textTubular airway segmentation is a prerequisite for bronchoscopic intervention in treating pulmonary diseases. Training convolutional neural networks (CNNs) for airway segmentation remains a clinical challenge due to the local discontinuities and distal small airway leakages caused by low resolutions and severe data imbalances. To address these issues, we propose an attention-driven refinement network, based on the degree of feature contribution, to improve the performance of fine-grained airway segmentation. A pointwise feature recalibration (PWFR) module is first designed to implement a differential feature treatment strategy by emphasizing competitive features and continuously suppressing redundant features, highlighting the prominence of airways in the learning task. Furthermore, a novel attention-driven knowledge distillation (AttdKD) module is developed to fully integrate the spatial and channel knowledge at various stages of the network, which strengthens the focus on distal small airways under conditions of class imbalance and mitigates the local discontinuity problem. The segmentation visualization results indicate that our refinement network effectively improves the thin airway recognition rate and improves the overall continuity of the airways under the guidance of the PWFR and AttdKD modules. The branches detected (BD) and tree length detected (TD) achieved scores of 93.96 %/81.7 % and 92.71 %/79.9 % on the ATM’22 and EXACT’09 datasets, respectively, and obtained scores of 92.72 %/92.44 % and 92.16 %/91.97 % on the abnormal case test sets of COVID-19 and Fibrosis, respectively. Extensive experiments demonstrate that our proposed method exhibits excellent sensitivity to distal small airways and achieves notable overall segmentation performance compared to the state-of-the-art (SOTA) baselines.</p
Influence of environment and microbes on corrosion behavior of welded steels in the LILW repositories (MICWEST-project)
No full textIntercomparison exercise of easy-to-measure and non-volatile difficult-to-measure analysis in homogenised high activity steel
No full textIntercomparison exercises (IE) are a way for laboratories to test their analytical performance. In case of difficult-to-measure (DTM) radionuclide analysis, participation in IEs are important due to the lack of reference materials. This paper reports the results from an IE focusing on non-volatile DTM analysis in homogenised high activity steel. The IE was carried out according to the ISO 13528 standard, in which the performances are assessed using z score. The z scores were generally acceptable. The experimental results were compared with activation calculation results showing wide range of compatibility.</p
Investigating the failure mechanisms of screen-printed reference electrodes
Get PDFStable reference electrodes are essential for reliable electrochemical measurements, including in electroanalytical devices, and for continuous environmental monitoring in particular, yet many SPREs are optimised for short-term, disposable use and their stability over multi-day operation remains limited. In this work, we target continuous monitoring, on the timescale of hours to weeks, where a compact, low-cost reference capable of maintaining a stable potential over time without requiring recalibration is essential. This study builds on our previous work on SPREs with polydimethylsiloxane (PDMS) junctions by systematically investigating their degradation mechanisms and the factors controlling operational lifetime. SPREs were fabricated on polyethylene terephthalate (PET) substrates using a KCl/poly(vinyl acetate) (KCl/PVAc) electrolyte reservoir and a PDMS junction.Electrochemical characterisation demonstrated that depletion of the internal KCl reservoir is the dominant failure mechanism, with reference potential drift exceeding 1 mV h−1 once the electrolyte is no longer able to maintain saturation. Incorporating a PDMS junction markedly reduced Cl− leaching, extending operational lifetimes from <0.2 days to over 18 days in 3 M KCl solution. Electrochemical impedance spectroscopy and SEM–EDS analyses indicated that, beyond electrolyte depletion, localised AgCl degradation also contributes to long-term instability.By quantifying the relationship between electrolyte volume, chloride retention, and potential drift, this work establishes direct links between SPRE structure, composition, and performance. These insights support improved SPRE designs for continuous monitoring applications and highlight the importance of junction integrity, water-resistant polymer components, and reproducible fabrication
Supplementing XYR1-mutated Trichoderma reesei strain cultivation with (SO2-ethanol-water) softwood pulp improves cellulase production
No full textThe cellulolytic enzyme cost remains a major bottleneck in converting lignocellulose, especially softwoods, into fuels and chemicals. The aim of this study was to evaluate possibilities to increase enzyme production efficiency by using SO 2-ethanol-water (SEW) pretreated softwood pulp with a Trichoderma reesei strain that expresses a mutant form of the main transcriptional regulator, XYR1, of cellulase- and hemicellulase genes leading to loss of glucose repression/carbon catabolite repression. The (hemi)cellulase enzyme cocktail of this strain was improved by expressing three heterologous enzymes, a beta-glucosidase, a CEL6 (CBH2) exoglucanase and a lytic polysaccharide mono‑oxygenase. Seven bioreactor cultivations were performed using glucose and different cellulose supplementations and glucose feed strategies. We showed that adding 3 %-w/v cellulose to the glucose medium and starting the glucose feed when the glucose was consumed from the batch medium, improved the protein production rate by over 80 % during the first five days compared to total absence of cellulose. With only 3 % cellulose addition to the batch phase, we estimate that over one third of time and total carbon source, including cellulose, could be saved compared to a production process without cellulosic substrate supplementation. Additionally, enzymes produced with SEW pulp in 119 h and those produced with glucose alone in 193 h both achieved 90 % glucose conversion when used for SEW pulp hydrolysis at a protein loading of 4–5 mg/g cellulose. Herein, we have shown that the M2883 strain can produce more than 29 FPU/mL of the complete set of cellulase enzymes both with and without cellulose supplementation.</p