HES-SO Fribourg

This study presents a one-year microbiological monitoring campaign conducted at the Oceanographic Institute of Monaco to evaluate microbial dynamics within a large public marine aquarium. The approach combined automated near-real-time flow cytometry, culture-based analyses, species identification, and antibiotic susceptibility testing. Continuous bacterial enumeration using the BactoSense® cytometer enabled high-resolution tracking of intact bacterial counts (ICC) across five hydraulic sectors, from seawater intake to exhibition tanks. The results revealed pronounced spatial gradients, with mean ICC values decreasing from 1.4 × 10⁵ cells mL⁻¹ at intake to below 1.3 × 10⁴ cells mL⁻¹ in internal tanks, confirming the high efficiency of UV-C disinfection and filtration systems. Seasonal analysis showed clear fluctuations at the intake, with peaks in spring and early summer associated with increased biological activity in the surrounding Mediterranean environment. Sector-specific variations indicated that hydraulic configuration and residence time influenced microbial stabilization, with localized differences in UV efficiency detected through near-real-time monitoring. Complementary bacterial identification revealed the presence of several opportunistic taxa, including V. fortis , V. harveyi , and Shewanella spp., typical of recirculating seawater systems. Antibiotic susceptibility testing revealed heterogeneous resistance profiles, with β-lactam resistance observed in several Vibrio isolates and multidrug resistance detected in S. algae and V. jasicida . The integration of biosensing, microbial identification, and resistance profiling provides an operational framework for evidence-based microbial surveillance in marine aquaria. These findings highlight the potential of automated near-real-time cytometry to enhance preventive management, support targeted interventions, and ensure microbiological stability in closed aquatic ecosystems. • First long-term marine use of the BactoSense® automated near-real-time flow cytometry system. • One-year monitoring revealed spatial and seasonal bacterial dynamics in a public aquarium. • UV-C disinfection and filtration reduced bacterial loads by more than one order of magnitude. • Hydraulic design and residence time shaped microbial stability across aquarium sectors. • Detection of opportunistic and resistant bacteria supports evidence-based aquarium management.

The transition toward a Circular Economy (CE) has received significant attention from academia, industry, and policymakers; however, manufacturing practices remain predominantly linear, generating waste and inefficiencies. This study addresses the lack of accessible sustainability assessment methods by introducing the Circularity Calculator (CC), a novel tool for evaluating circular strategies during the early phases of process development. Unlike existing assessment frameworks, which often require extensive data and customization, the CC can be integrated directly to existing processes to combine environmental and economic impact into a streamlined evaluation process for early decision-making. The research involves collaboration with a leading German automotive manufacturer. Site visits and interviews enabled the identification of material flows and primary waste streams, which informed the definition of relevant indicators. The CC generates a dimensionless index, enabling comparison and prioritization of proposed scenarios without relying on supply-chain-wide data, which is often unavailable at early stages. Implications demonstrate the adaptability of the CC across industrial contexts, supporting conceptual planning and operational phases. Its intuitive design facilitates adoption by practitioners without extensive expertise in sustainability. The tool represents an advance in CE assessment, contributing to Sustainable Development Goals (SDGs) 9, 12, and 17 by promoting sustainable industrial practices, resource circularity, and collaborative evaluation frameworks.

Abstract Phenylenediamines (PDs) and their N,N′ -substituted derivatives (PPDs) are widely used antiozonants in rubber and polymer manufacturing, with significant release into the environment via tire wear particles. Once emitted, they undergo oxidative transformations, producing quinone derivatives and other products through ozonolysis, photooxidation, and hydrolysis. Among these transformation products, quinone derivatives are the most extensively studied due to their enhanced stability and high toxicity, exemplified by 6PPDQ-induced mortality in coho salmon at ng/L levels. Their occurrence has been reported in water, soils, air, dust, and food products, raising concerns over ecological risks and potential human exposure. This review critically assesses current analytical methodologies, highlighting liquid chromatography–mass spectrometry as the most powerful tools, complemented by tailored extraction approaches such as solid-phase extraction (SPE), liquid–liquid extraction (LLE), Quick, Easy, Cheap, Effective, Rugged, and Safe extraction (QuEChERS), and accelerated solvent extraction (ASE). Despite methodological advances, major challenges persist, including low environmental concentrations, chemical instability, and lack of certified standards. Future priorities include harmonized protocols, interlaboratory validation, and development of emerging analytical and real-time monitoring technologies.

Abstract On February 2, 2024, a landslide of several hundred cubic meters caused several massive rocks (50 to 100 m 3 ) to fall down the slope of Vevey valley region in Switzerland. The rockslide hit and damaged part of the structure of the A9 Lausanne‐Saint‐Maurice national road/bridge before settling at the bottom of the slope near the bridge foundation. Luckily, the rockslide did not cause any casualties, nor did it affect any homes. Noting that the structure “Pont de Veveyse” consisting of 2 parallel and identical composite steel and prestressed concrete bridges that was put into service in 1969 ensures the passage of approximately 61000 vehicles/ day. In the bridge region, the geological conditions are very complicated and are characterized by an extended sliding zone that experiences slippage of a few cm per year. Since in this region, erosion and thus, slope as well as rockslides occur naturally and often, the following study was performed to determine the behavior of the bridge under different rockslide impacts. Following the accident, field investigations were conducted to gather information and identify the trajectory of the rockslides and bridge damage. Then, based on the principle of linear impulse and momentum as well as the conservation of linear impulse and momentum, the velocity of rockslides as well as the average impulse forces were calculated. The obtained results were used in the numerical simulations performed using the nonlinear software Abaqus to investigate the bridge behavior and responses caused by the impact of the massive rockslide. The effects of impact load, its direction and location on the behavior of the bridge were examined. The obtained results showed that the simulated damage mechanisms agree with field observations. Moreover, bridge stability is affected by the rockslide impacts. The obtained results can be considered a mean to assess the stability of the bridge and perform as guidelines for authorities to mitigate future hazard rockslides impact strategies for the A9 bridge.

As a field, haptics encompasses a wide and diverse array of technologies, modalities, and applications, which makes it challenging to understand, classify, and compare comprehensively. In this paper, we introduce Haptree: a design space framework developed based on a review of existing literature and building on top of existing taxonomies. Unlike other haptic frameworks that focus on specific aspect of haptics, Haptree is intended to show the big picture of haptic experiences, connecting together aspects of haptic experience that used to be isolated in other frameworks. Haptree maps haptic experiences in five different stages, from hardware characteristics to end-user applications. It provides practical guidelines for designing new haptic experiences by referencing existing approaches and use cases, or pointing to a current gap in the literature. Furthermore, Haptree is intended to be a community-driven tool, designed for iterative refinement and contribution by the haptic research community. Finally, we outline future steps, including validating and enhancing Haptree through community engagement and empirical studies.

Abstract The built environment is a major contributor to global CO 2 emissions, with 37% of total emissions. While efforts to reduce building emissions have progressed, the impact of outdoor spaces remains largely unquantified. Existing carbon accounting frameworks focus primarily on building structures, leaving outdoor landscaping overlooked in emissions assessments. Furthermore, there is a lack of literature addressing the carbon footprint of these spaces, particularly in relation to their contribution to overall building emissions. This study aims to bridge this gap by assessing the carbon impact of outdoor surfaces and integrating them into construction-related emissions evaluations. A four-step methodology is applied: (1) defining the functional unit as one m 2 of low-traffic urban surface, (2) identifying commonly used materials, (3) performing a Life Cycle Assessment (LCA) to determine the carbon emissions of each material, and (4) integrating these emissions into the building’s overall carbon budget using urban planning regulations and building archetypes. The results highlight significant variations in emissions depending on material choices. Gravel has the lowest impact, while perforated concrete paving also performs well due to its reduced cement content. In contrast, natural stone can generate up to 10 times more CO 2 than gravel when polished and transported over long distances. In the end, when outdoor areas are fully utilized, they can account for up to 20% of a building’s carbon footprint. This underscores the need for integrating outdoor surface regulations into urban planning. By providing insights for architects and policymakers, this research supports the development of more sustainable built environments.

Abstract This study investigates the potential of hardwood as a complementary structural material for reducing embodied greenhouse gas (eGHG) emissions in buildings, responding to the growing interest of substituting concrete. Historically, operational emissions have been significantly reduced through improved thermal insulation and renewable energy integration, shifting attention toward eGHG emissions. While softwood is chosen to replace concrete in structural applications, resource limitations restrict its scalability. This research quantitatively assesses hardwood as a complementary alternative. The methodology involves identifying representative building typologies in Switzerland from energy performance databases and selecting two contemporary objects as benchmark case studies. Life cycle assessments (LCA) of these buildings establish eGHG emissions benchmarks. Timber alternatives, employing both soft- and hardwood, are developed according to practical construction requirements, structural safety, serviceability (vibration control), and fire safety criteria. Comparative LCAs of these timber typologies, based on Swiss standards (SIA 2032 and KBOB database), quantify potential eGHG emission reductions in comparison to concrete construction. The results reveal that timber substitutions consistently lower eGHG emissions compared to concrete. Although hardwood generates 20-100% higher emissions at the element production level, due to its density and processing demands, building-level analyses demonstrate comparable eGHG emissions reductions for both timber types. Multi-box slab elements significantly outperform traditional joist construction in material efficiency, minimizing slab thickness and related building height. Furthermore, structural over-dimensioning for fire safety proves more environmentally advantageous than protection panels when fire safety requirements are limited. Overall, hardwood emerges as a credible solution to complement timber typologies, enabling substantial eGHG emission reductions.