National Institute of Scientific Research

Biofilms are increasingly used as tools for biomonitoring disturbed environments, for example, in urban, agricultural, and mining contexts. In this study, we used biofilms as integrators and bioindicators of metal contamination of Lone Elm Creek, a highly contaminated stream within the Tri-State Mining District in Joplin, Missouri (USA). We sampled biofilms upstream and downstream of a mine adit and analyzed metal content (Fe, Zn, Cd and Pb), diatom assemblage composition, and the presence and severity of frustule teratologies. Physico-chemical analyses showed marked differences in nitrogen and oxygen concentrations at the first site downstream of the mine adit. Metal concentrations in the water were elevated at all sites and did not vary markedly along the upstream–downstream gradient. In addition to metallic contamination from mine tailings, legacy of past activities may represent other sources of contamination. Diatom assemblage composition differed markedly at the site immediately downstream of the mine adit compared to other sites. The presence of frustule deformities as well as their type and their severity were investigated. Ulnaria ulna, Achnantidium minutissimum, and Fragilaria austriaca were the most frequently deformed diatoms and showed the most severe abnormalities. However, the percentage of teratologies was not correlated with metal concentrations in the water or in the biofilm. Metal bioaccumulation in the biofilm as a function of metal concentration in the water fitted well to predictive models developed in previous studies, highlighting the potential of biofilms to be used as a tool to assess exposure to metal contamination.

Drought is a critical global environmental crisis that severely impacts wetlands, leading to ecosystem degradation. While numerous studies have explored various drought aspects, most focus on one or two key categories, neglecting a holistic approach that integrates all influencing factors. This study addresses this gap by developing a Comprehensive Drought Index (CDI) that combines climatic, agricultural, hydrological, and anthropogenic parameters. Utilizing satellite observations from 2000 to 2023 for the Anzali Wetland in Iran, we modeled drought’s multifaceted impacts through the computation of several drought indices, including the Standardized Precipitation Index (SPI), Palmer Drought Severity Index (PDSI), Soil Moisture Condition Index (SMCI), Temperature Condition Index (TCI), Vegetation Condition Index (VCI), Surface Water Supply Index (SWSI), Precipitation Condition Index (PCI), and Urban Thermal Field Variance Index (UTFVI). These indices were integrated into a comprehensive drought map using a weighted approach based on the correlation between SPI and the other indicators, with correlations exceeding 70%, underscoring the model’s accuracy. The resulting CDI provided a holistic drought assessment for the wetland. Results revealed 2019 as a wet year for the Anzali Wetland, while 2021 experienced a significant drought. Change detection analysis using Sentinel radar and optical data for 2019, 2021, and 2023 identified substantial human-induced land cover alterations, particularly in water areas. Between 2019 and 2021, 44% of water areas experienced human-made changes, which increased to 61% by 2023. A machine learning model trained with limited samples from 2019 achieved an overall accuracy of 92.92% and a Kappa coefficient of 87.16% and was subsequently applied to 2021 and 2023 data. The findings highlight severe drought conditions threatening the Anzali Wetland’s ecosystem, with human interference exacerbating the risk of total degradation.

Anion exchange membrane fuel cells (AEMFCs) are among the most promising sustainable electrochemical technologies to help solve energy challenges. Compared to proton exchange membrane fuel cells (PEMFCs), AEMFCs offer a broader choice of catalyst materials and a less corrosive operating environment for the bipolar plates and the membrane. This can lead to potentially lower costs and longer operational life than PEMFCs. These significant advantages have made AEMFCs highly competitive in the future fuel cell market, particularly after advancements in developing non‐platinum‐group‐metal anode electrocatalysts, anion exchange membranes and ionomers, and in understanding the relationships between cell operating conditions and mass transport in AEMFCs. This review aims to compile recent literature to provide a comprehensive understanding of AEMFCs in three key areas: i) the mechanisms of the hydrogen oxidation reaction (HOR) and the oxygen reduction reaction (ORR) in alkaline media; ii) recent advancements in the synthesis routes and structure‐property relationships of cutting‐edge HOR and ORR electrocatalysts, as well as anion exchange membranes and ionomers; and iii) fuel cell operating conditions, including water management and impact of CO2. Finally, based on these aspects, the future development and perspectives of AEMFCs are proposed.

The tambaqui (Colossoma macropomum, G. Cuvier 1818) thrives both in the ion‐poor waters of the Amazon and in commercial aquaculture. In both, environmental conditions can be harsh due to low ion levels, occasional high salt challenges (in aquaculture), low pH, extreme PO2 levels (hypoxia and hyperoxia), high PCO2 levels (hypercapnia), high ammonia levels (in aquaculture), and high and low temperatures. Ion transport across the gill is affected by active transport processes, passive diffusive permeability, ion concentrations (the chemical gradient), and transepithelial potential (TEP, the electrical gradient). The latter is a very important indicator of ionoregulatory status but is rarely measured. Using normoxic, normocapnic, ion‐poor, low–dissolved organic carbon (DOC) well water (27°C, pH 7.0) as the acclimation and reference condition, we first confirmed that the strongly negative TEP (−22.3 mV inside relative to the external water) is a simple diffusion potential. We then evaluated the effects on TEP of more complex waters from the Rio Negro (strong hyperpolarization) and Rio Solimões (no significant change). Additionally, we have quantified significant effects of acute, realistic changes in environmental conditions—low pH (depolarization), hypercapnia (depolarization), hypoxia (depolarization), hyperoxia (hyperpolarization), elevated NaCl concentrations (depolarization), and elevated NH4Cl concentrations (depolarization). The TEP responses help explain many of the changes in net Na⁺ flux rates reported in the literature. We have also shown marked effects of temperature on TEP and unidirectional Na⁺ flux rates (hyperpolarization and decreased fluxes at 21°C, depolarization and increased fluxes at 33°C) with no changes in net Na⁺ flux rates. Calculations based on the Nernst equation demonstrate the importance of the TEP changes in maintaining net Na⁺ balance.

From a conservation perspective, it is important to identify when sub-lethal temperatures begin to adversely impact an organism. However, it is unclear whether, during acute exposures, sub-lethal cellular thresholds occur at similar temperatures to other physiological or behavioural changes, or at temperatures associated with common physiological endpoints measured in fishes to estimate thermal tolerance. To test this, we estimated temperature preference (15.1±1.1°C) using a shuttle box, agitation temperature (22.0±1.4°C) as the point where a fish exhibits a behavioural avoidance response and the CTmax (28.2±0.4°C) as the upper thermal limit for 1 yr old brook trout (Salvelinus fontinalis) acclimated to 10°C. We then acutely exposed a different subset of fish to the mean temperatures associated with the pre-determined physiological endpoints and sampled tissues when they reached the target temperature or after 60 min of recovery at 10°C for transcriptomic analysis. We used qPCR to estimate mRNA transcript levels of genes associated with heat shock proteins, oxidative stress, apoptosis, and inducible transcription factors. A major shift in the transcriptome response occurred once the agitation temperature was reached, which may identify a possible link between the cellular stress response and the behavioural avoidance response.

High-dimensional photon states (qudits) are pivotal to enhance the information capacity, noise robustness, and data rates of quantum communications. Time-bin entangled qudits are promising candidates for implementing high-dimensional quantum communications over optical fiber networks with processing rates approaching those of classical telecommunications. However, their use is hindered by phase instability, timing inaccuracy, and low scalability of interferometric schemes needed for time-bin processing. As well, increasing the number of time bins per photon state typically requires decreasing the repetition rate of the system, affecting in turn the effective qudit rates. Here, we demonstrate a fiber-pigtailed, integrated photonic platform enabling the generation and processing of picosecond-spaced time-bin entangled qudits in the telecommunication C band via an on-chip interferometry system. We experimentally demonstrate the Bennett-Brassard-Mermin 1992 quantum key distribution protocol with time-bin entangled qudits and extend it over a 60 km-long optical fiber link, by showing dimensionality scaling without sacrificing the repetition rate. Our approach enables the manipulation of time-bin entangled qudits at processing speeds typical of standard telecommunications (10 s of GHz) with high quantum information capacity per single frequency channel, representing an important step towards an efficient implementation of high-data rate quantum communications in standard, multi-user optical fiber networks.

RF-sputtering is used to deposit Ti4O7-Magneli-phase films onto various substrates at deposition temperatures (Ts) ranging from 25 to 650 °C. Not only the structural, but also electrical conductivity, optical absorbance and photothermal properties of the Ti4O7 films are shown to change significantly with Ts. A Ts of 500 °C is pointed out as the optimal temperature that yields highly-crystalized pure-Ti4O7-Magneli phase with a densely-packed morphology and a conductivity as high as 740 S/cm. The Ti4O7 films deposited at Ts = 450–500 °C also exhibited the highest optical absorption over all the broad (200–1500) nm range. The absorbed sunlight (AM1.5) was efficiently converted into heat by raising the temperature of the Ti4O7 films up to ~ 54 °C. Thus, the external photothermal efficiency (ηext) of the Ti4O7 films, was found to be as high as ~ 74%. This is the highest ηext reported so far for sputtered-Ti4O7 coatings (just ~ 450 nm-thick), highlighting their significant potential for photothermal applications such as desalination, deicing and/or smart windows. Finally, the ηext of the Ti4O7 coatings is demonstrated, for the first time, to be linearly correlated to their integrated light absorption coefficient. This fundamental relationship paves the way towards the design and optimization of highly efficient solar-thermal conversion devices.

The cumulative effects of human activities and natural pressures pose significant threats to ecosystem functioning and global biodiversity. Assessing the cumulative impact of multiple stressors—whether acting simultaneously or sequentially and directly or indirectly—is challenging due to their complex interactions. Consequently, these interactions may be unintentionally overlooked or disregarded in management decisions. While existing reviews have focused on coastal and freshwater ecosystems, analyses specifically targeting salmonids as a focal group are lacking. This research presents the first quantitative and qualitative assessment of stressor interactions affecting salmonid biology and physiology. A focused literature search identified 118 experimental trials with multiple stressors on salmonids. From these, 46 cases were considered suitable for the quantitative analysis. We calculated Hedges’ g effect sizes to classify the interactions between multiple stressors as additive, synergistic, or antagonistic. Our findings revealed that additive effects were found most frequently (50% of interactions), followed by synergistic (30.5%) and antagonistic (19.5%) interactions. Additionally, we performed a network analysis including cases focusing on the influences of multiple stressors interactions (n = 38). Our qualitative analysis identified temperature, metals, and pesticides as the most paired stressors across the three types of interactions. The findings of this research highlight the potential vulnerabilities of salmonids and their habitats by identifying key interactions between multiple stressors, and priorities for future research. Understanding these interactions and cumulative effects, particularly in the context of climate change, can inform targeted conservation and management strategies, contributing to the preservation of these important fish species and their ecosystems, which are vital to local human communities.

We have shown that virus-specific CD4 and CD8 memory T cells (TM) induce autophagy after T cell receptor (TCR) engagement to provide free glutamine and fatty acids, including in people living with HIV-1 (PLWH). These nutrients fuel mitochondrial ATP generation through glutaminolysis and fatty acid oxidation (FAO) pathways, to fulfill the bioenergetic demands for optimal IL-21 and cytotoxic molecule production in CD4 and CD8 cells, respectively. Here, we expand our knowledge on how the metabolic events that occur in the mitochondria of virus-specific TM down-stream of the autophagy are regulated. We show that HSP60 chaperone positively regulates the protein levels for multiple glutaminolysis- and FAO-related enzymes, thereby actively fueling the levels of cellular alpha-ketoglutarate (αKG) and related mitochondrial ATP-dependent antiviral T cell immunity in both CD4 and CD8 TM. Finally, we provide a way to rescue defective ATP generation in mitochondria and dependent effector functions in virus-specific TM including anti-HIV-1 protective responses, when HSP60 expression is impaired after TCR engagement in patients, in the form of dimethyl 2-oxoglutarate (DMKG) supplementation.

This paper presents a high-performance circularly polarized (CP) magneto-electric (ME) dipole antenna optimized for wideband millimeter-wave (mm-wave) frequencies, specifically targeting advancements in 5G and 6G technologies. The CP antenna is excited through a transverse slot in a printed ridge gap waveguide (PRGW), which operates in a quasi-transverse electromagnetic (Q-TEM) mode. Fabricated on Rogers RT 3003 substrate, selected for its low-loss and cost-effective properties at high frequencies, the design significantly enhances both impedance and axial ratio (AR) bandwidths. The antenna achieves an impressive impedance bandwidth of 31% (25.24–34.50 GHz) and an AR bandwidth of 24.9% (26.40–33.91 GHz), with a peak gain of up to 8.4 dBic, demonstrating a high cross-polarization level. The experimental results validate the high-performance characteristics of the antenna, making it a robust candidate for next-generation wireless communication systems requiring CP capabilities.

Family structures in Western societies have become complex and diverse over the past six decades, shaped by evolving sociocultural norms and changing marital trends. While divorce rates have declined since 2000, they remain higher than in the 1960s. This history of marital instability has resulted in a rise in stepfamilies, highlighting the importance of understanding intergenerational dynamics within stepfamilies. This scoping review aims to synthesize scientific data regarding the intergenerational relationships between stepgrandparents and stepgrandchildren within stepfamilies in Western countries. To this end, a comprehensive scoping review was conducted following the methodology established by the Johanna Briggs Institute. Results indicate that grandchildren generally feel closer to their biological grandparents than to their stepgrandparents. The relationship quality between stepgrandparents and stepgrandchildren is influenced by factors as age, gender, and family history of both stepgrandparents and stepgranchildren. Future research should examine how cultural, socio-economic, and intersectional factors influence stepgrandparental roles.

Site-specific heterogeneity in geological materials plays a crucial role in groundwater (GW) and surface water (SW) interaction, especially in ecosystems sensitive to groundwater influx; for example, salmonid habitats are influenced by localized GW input to streams. While numerous methods have emerged to better understand mechanisms governing GW–SW interaction, few studies compare these methods directly. Therefore, the objective of this study is to evaluate the strengths and limitations of an innovative active heat tracing method to quantify the role of riverbed heterogeneity on GW–SW exchanges. This method was compared with several established techniques such as seepage meters, piezometers, and passive heat tracing at a field site on the Sainte-Marguerite River in Quebec, Canada. The measured spatial variation of the exchange rates due to the presence of a sandbar with coarse materials was shown to be statistically significant. Additionally, temporal analysis helped to identify variations of GW flux even during the cold season when GW flux was expected to be limited due to frozen ground and low infiltration from the snow-covered ground surface. Seepage meters and active heat tracing allowed for spatial analysis of GW–SW interaction, while piezometers with water level loggers and passive heat tracing with installed temperature sensors in the riverbed were convenient for identifying temporal variation of GW–SW exchange rates. The combination of temperature sensors and a heating cable was used for the first time as a tool for active heat tracing and showed good potential to evaluate riverbed thermal properties and GW seepage rates in the river.

The production of storable hydrogen fuel through water electrolysis powered by renewable energy sources such as solar, marine, geothermal, and wind energy presents a promising pathway toward achieving energy sustainability. Nevertheless, state‐of‐the‐art electrolysis requires support from ancillary processes which often incur financial and energy costs. Developing electrolysers capable of directly operating with water that contains impurities can circumvent these processes. Herein, we demonstrate the efficient and durable electrolysis of saline water to produce chlorine gas (Cl2) and hydrogen using structurally ordered IrB1.15, synthesized through ultrafast joule heating. IrB1.15 exhibits remarkable performance, achieving overpotentials of 75 mV for the chlorine evolution reaction (CER) and 12 mV for hydrogen evolution reactions (HER) at current densities of 10 mA cm⁻². Moreover, IrB1.15 displays a durability of over 90 h towards both CER and HER. Density functional theory reveals that IrB1.15 has adsorption energies significantly closer to 0 eV for Cl and H, compared to IrO2 and Pt/C. Furthermore, in situ Raman investigations reveal that Ir in IrB1.15 serves as the active center for CER, while the introduction of B atoms to Ir lattices mitigates the formation of absorbed hydrogen species on the Ir surface, thereby enhancing the performance of IrB1.15 in HER.

This study presents an innovative life cycle assessment (LCA)-centric approach for optimizing the mix design of alkali-activated materials (AAMs) as sustainable alternatives to ordinary portland cement (OPC). The AAMs are developed using electric arc furnace slag (EAFS) and fly ash as precursors. The environmental performance is evaluated using the ReCiPe midpoint methodology, considering both mass and economic allocation methods. The results indicate that global warming potential and terrestrial ecotoxicity are the primary environmental impact categories across all mixes and allocation scenarios. A Taguchi-based hybrid optimization technique, integrating gray relational analysis (GRA) and analytical hierarchical process (AHP)-weighted GRA, is employed to determine the optimal mix design based on fresh properties, mechanical performance, durability, and sustainability indices. The AHP-GRA analysis reveals that mixes containing at least 50% EAFS perform better than OPC in terms of overall sustainability. A blend of 75% EAFS and 25% fly ash is recommended for achieving the best balance between performance and environmental impact, offering a promising alternative for sustainable construction practices.

The combination of a Solar Assisted Geothermal Heat Pump system (SAGHP) with a multi-zone greenhouse is investigated to take advantage of water flooding in abandoned open pit mines in Canada. The envisioned system includes an Air Handling Unit (AHU), Heat Recovery Ventilation (HRV), daily Thermal Energy Storage (TES), and daily Domestic Hot Water (DHW). The main objective is to satisfy the greenhouse heating, cooling, and dehumidification loads, for the considered application, while minimizing energy consumption. This analysis is conducted using data extracted from a case study of a commercial, multi-zone greenhouse, considering different daily weather conditions throughout a year. To reduce the computation time, a clustering approach based on the K-Means method is applied to obtain a small number of typical weather days. Elbow, Dendrogram, and Silhouette approaches confirmed that it is possible to represent a year as six different Typical Days (TD), which can be further categorized as Heating only (TD1 and TD2), Heating/Cooling (TD3 and TD4), and Cooling only (TD5 and TD6). Dynamic Pinch Approach (DPA) showed a great ability to target the minimum energy consumption and maximize the potential heat recovery for each typical day. The study focuses on energy targeting, with discussion of preliminary design considerations, such as the solar hot water (SHW) system, Thermal Energy Storage (TES), and heat pumping. Results revealed that mine water can significantly improve the energy system efficiency, specifically where heating/cooling or only cooling is dominant (TD3, TD4, TD5, and TD6). For instance, by integrating an AHU with the greenhouse for the TDs where heating/cooling is dominant, 22.5% energy saving is achievable. The incorporation of heat pumping, waste heat recovery, and solar thermal collectors through mixed direct/indirect heat recovery (i.e. via TES) can reduce hot utility usage in the considered application by as much as 40%.