Search Results (992)

Currently, more than half of Pyrenean high mountain lakes are occupied by fish as a result of historical introductions that date back centuries and which have accelerated during the last 70 years. In the southern slope of these mountains, the main fish that have been introduced are Brown trout (Salmo trutta), Brook trout (Salvelinus fontinalis), Rainbow trout (Oncorhynchus mykiss), and European minnow (Phoxinus sp). The specific impacts of the introduction of fish include, among others, the transformation of the ecosystem structure and trophic relationships, and the reduction and extirpation of native species. The project LIFE RESQUE ALPYR (LIFE20 NAT/ES/000369), started in 2022 and ending in 2026, includes among its main objectives the restoration of ten high mountain lakes with fish (trout or minnow) and the recovery of native species of European interest by the eradication of introduced fish. We planned and executed continuous and sustained campaigns to achieve the complete removal of fish. From 2022, we began with operations in seven objective lakes by means of several capture techniques, mainly gill nets for trout and a combination of gill nets, fyke-nets, and electrofishing for minnows. In 2024 and 2025, in three other lakes, chemical treatments with rotenone were carried out to achieve rapid eradication of fish. Currently, we have already achieved the complete removal of fish in four lakes, either with sustained capture or chemical treatments. In the other three lakes, this objective is also expected to be achieved in 2026, and only few individuals persist in actuality. In the other two lakes, the European minnow has been removed, and trout are now the focus of a two-stage strategy. In the remaining lake, we have only achieved a reduction in the European minnow (>50% reduction), with trout still remaining. We present, in detail, the methodologies applied and the results obtained. Full article

Total suspended solids (TSS) have been shown to damage the structural integrity of fish gills, impairing their function, including gas exchange. However, studies showing linkages between gill damage due to TSS and fish performance are limited. There is a large diversity of fish species inhabiting aquatic environments, and whether the TSS impact on gill function is similar across a range of species has yet to be explored. Here, we exposed multiple species, including salmonids (rainbow, brook and cutthroat trout) and cyprinids (fathead minnow and longnose dace) to a range of TSS concentrations (0–1000 mg L⁻¹) for 4 d and assessed damages to gill structure (filament thickness, lamellae thickness, oxygen diffusion distance, lamellae length, epithelial lifting, and interlamellar distance) using confocal microscopy. All species tested showed similar gill structural damage, including thicker lamellae, longer oxygen diffusion distances, and reduced respiratory surface area, at concentrations ≥ 100 mg L⁻¹ TSS. To assess whether gill damage corresponds to performance dysfunction, we tested the metabolic rate and swimming capacity of a salmonid (rainbow trout) and a cyprinid (fathead minnow) after exposure to 100 mg L⁻¹ TSS using swim tunnel respirometry. Trout showed lower routine metabolic rate (RMR) and maximum metabolic rate (MMR) after TSS exposure and were unable to reach the higher swimming speeds attained by unexposed fish. Fathead minnows showed no difference in the RMR after TSS exposure, but, like trout, had a lower MMR and were unable to attain the higher swimming speed of the control fish. Both species showed a ~35% reduction in the critical swimming speed (U_crit). These findings reveal that environmentally realistic TSS concentrations damage gill structure, impair fish swimming performance, and may compromise their ability to cope with energy-demanding activities, including additional biotic and abiotic stressors. Full article

Autonomous navigation of unmanned surface vehicles (USVs) in complex obstacle scenarios remains challenging due to redundant perception inputs, unstable value estimation, and inefficient policy convergence. To address these problems, this paper proposes LDA-D3QN, an improved deep reinforcement learning method for USV autonomous navigation. The proposed method constructs a compact navigation state representation by combining target-related information with local obstacle features, allowing the agent to retain key decision-making information while reducing unnecessary environmental redundancy. Based on this representation, an enhanced value-learning framework is developed to improve the stability of navigation decisions in cluttered environments. Moreover, a reward-guided and staged training strategy is introduced to help the agent gradually adapt to increasingly complex navigation tasks. The proposed method was evaluated on a Unity–ROS–MATLAB integrated simulation platform. Experimental results show that LDA-D3QN achieves superior overall navigation performance compared with several representative reinforcement learning algorithms. Specifically, the proposed method achieves a final training success rate of 91.4%, outperforming PPO (82.3%), Dueling DQN (78.5%), Double DQN (79.8%), and Rainbow DQN (86.5%). Additional tests in complex multi-obstacle and multi-target scenarios further demonstrate that the learned policy can generate safe, stable, and effective navigation behaviors. Preliminary validation using real-USV sensor data also confirms the feasibility of the LiDAR and GPS data processing procedures, providing a basis for future closed-loop autonomous navigation experiments and multi-sensor fusion deployment. Full article

The use of insect-based protein sources in aquaculture is gaining increasing attention with Hermetia illucens (black soldier fly, BSF) larvae meal representing a promising substitute to fishmeal (FM). This study evaluated the effect of partial dietary inclusion of BSF meal (BSF0, BSF2.5, BSF5, BSF10%) on the volatilome of rainbow trout (Oncorhynchus mykiss) fillets, before and after cooking, using gas chromatography–mass spectrometry (GC–MS) and a metal oxide sensor-(MOX)-based device. Fish were fed diets with increasing BSF inclusion, and both raw and cooked fillets were analyzed to assess changes in volatile organic compounds (VOCs). GC–MS enabled the identification and semi-quantitative analysis of VOC classes, while MOX sensor responses were processed using Linear Discriminant Analysis (LDA) to assess discrimination among dietary treatments. Results showed that BSF inclusion influenced the volatile profile, with clearer separation at higher inclusion levels (BSF5–BSF10%), especially in cooked fillets. Thermal processing enhanced these differences. GC–MS analysis revealed a reduction in aldehydes and ketones and an increase in carboxylic acids with higher BSF inclusion. Key compounds such as hexanal and heptanal decreased, indicating changes in lipid-derived volatile pathways. Overall, the integration of GC–MS and MOX sensors proved effective in detecting diet-induced changes, supporting their application as effective and reliable tools for quality assessment in aquaculture products, with potential implications for sensory quality that should be further confirmed through dedicated sensory studies. Full article

Introduction: The 3 Rs principle advocates developing alternative, biologically relevant models. Thus, 3D fish liver in vitro models have been increasingly used for ecotoxicological studies. We previously optimized spheroids from the rainbow trout non-tumoral liver cell line RTL-W1 and employed them to assess the effects of aquatic pollutants. Although they demonstrated potential for assessing ecotoxicological effects, further optimization is warranted to enhance their physiological relevance. Incorporating an extracellular matrix (ECM), such as collagen, has been shown to be a promising strategy to improve spheroids’ structural organization and functionality. Objective: This study aimed to optimize 3D culturing conditions of RTL-W1 spheroids by evaluating the effects of collagen supplementation on viability, morphology, and functional response. Methodology: Spheroids from the RTL-W1 cell line (60,000 cells per well) were cultured in 96-well ultra-low attachment (ULA) plates at 18 °C. After spheroids’ formation, rat tail collagen was supplemented at concentrations of 15 (C15), 30 (C30), and 60 (C60) µg/mL at culture days 7, 8, and 9. Spheroids were collected at two sampling days (10 and 14). Viability was assessed using alamarBlue and lactate dehydrogenase (LDH) assays, while morphology was assessed by optical microscopy. Collagen penetration was evaluated using Masson’s trichrome staining technique. Protein expression of cytochrome P450(CYP)1A was assessed by quantifying immunocytochemistry staining using an anti-CYP1A antibody. Results: On day 10, LDH leakage decreased in C15 and C60, compared with the control, whilst C15 spheroids showed lower absorbance levels in the alamarBlue assay. On day 14, LDH showed no significant differences; however, C30 and C60 had higher alamarBlue absorbance, indicating greater metabolic capacity. Spheroid morphology appeared intact in all conditions. Masson trichrome revealed collagen fibrils at the periphery of the spheroids, especially in C30 and C60, indicating that spheroids incorporated collagen. CYP1A immunostain was present in all conditions, localized in the spheroids’ border, and tended to be higher when supplementation occurred in earlier days. Conclusions: Our results suggest that RTL-W1 spheroids interacted with the collagen matrix and appeared to functionally improve. Data suggest that incorporating ECM may increase the complexity and physiological relevance of RTL-W1 spheroids, thereby better supporting mechanistic and ecotoxicological applications. Full article

In this study, passive acoustic technology was used to obtain sound signals indicative of feeding in individual rainbow trout (Oncorhynchus mykiss). Feeding signals were separated from background signals to characterize their acoustic parameters, in order to quantify feeding activity. The audio and video data of rainbow trout during feeding were synchronized to determine the signal category and mark it, and the time-domain features and frequency-domain features of fish swallowing feed were extracted. This not only has important theoretical value for in-depth understanding of fish growth, reproduction, and other life activities, but also provides data support and technical recommendations for future research on this topic. Full article

Integrated care is increasingly shaped by digital infrastructures, data governance, and AI-enabled analytics, yet the relevant literature remains fragmented across health-services research, digital health, and machine learning. This article reports a scoping review, conducted in line with PRISMA-ScR guidance, that maps how integrated care models have evolved conceptually, what digital and AI-enabled infrastructures support them, how their clinical, economic, and equity impacts can be evaluated, and what current implementations imply for sustainable scaling. We searched PubMed, Scopus, Semantic Scholar, and Crossref (retrieval date 31 October 2025; forward screening to 31 March 2026) and added grey literature from named policy bodies. The searches identified 15,189 records, reducing to 11,789 after intra- and cross-source deduplication and grey-literature integration; 620 full texts were assessed and 192 were included in the synthesis. Four domains were synthesised: conceptual foundations of integrated care, AI and multimodal analytics, implementation barriers, and digital-governance foundations. We chart the field using a Type I–V maturity scheme (disease, cohort, whole-system, digital-integrated, learning), benchmarked against the Rainbow, MacColl, EMRAM/AMAM, and NHS ICS models. Most deployments cluster at digitally integrated but only weakly adaptive Type IV; recurrent failure modes—temporal blind spots, maintenance debt, semantic drift, and governance gaps—block progression to Type V, and high-profile clinical-AI failures illustrate the cost of attempting Type V analytics on Type IV-or-worse infrastructure. A walk through nine world regions maps each to its current Type I–V position and shows that organisational and payment integration—not digital sophistication alone—is currently the dominant driver of progress. The COMFORTage Integrated Care Model Library is positioned as a workflow of AI agents orchestrating predictive, preventive, and personalised care across the integrated-care lifecycle rather than as a single federated-learning programme. The review positions AI-enabled integrated care less as a finished model than as an emerging design space requiring longitudinal data assets, stewarded model lifecycles, accountable governance, and outcome-based contracting for clinically useful, equitable, and trustworthy learning systems. Full article

Serverless computing has emerged as a prominent research focus in cloud computing because it provides infrastructure-transparent development and elastic resource management. However, this computing paradigm still faces the inherent challenge of cold start. Existing approaches have two major limitations: insufficient workload prediction accuracy and inefficient allocation of reusable container replicas to incoming function requests. To address these challenges, we propose a container scheduling approach based on Workload Prediction and Particle Swarm Optimization (PSO), named WPPSO. WPPSO first leverages a code-pre-trained large language model (LLM) to extract intrinsic function features and then uses a spatio-temporal fusion-based temporal neural network (STF-TNN) to predict serverless workloads. It subsequently employs a greedy algorithm to construct a high-quality initial matching state and uses PSO to refine the container scheduling strategy. Finally, WPPSO introduces a hierarchical container recycling mechanism to reduce idle resource waste. Extensive experiments show that WPPSO reduces startup latency by up to 72.2% and memory footprint by 63.4% compared with the native Knative platform. Compared with RainbowCake, WPPSO achieves a 15.6% lower mean startup latency without statistical significance and a statistically significant 31% reduction in idle memory consumption. Full article

Phagocytosis in vitro assays are widely used to assess the health status of fish, since it may be affected by diseases and environmental factors. To date, studies have evaluated phagocytosis in fish by observing fluorescent beads or bacteria engulfed by phagocytes. However, particles adhering to the external surface of the phagocyte membrane cannot be easily distinguished from those that are truly internalized. This work aimed to: (1) test whether a pHrodo™ (pHR)-based method improves the accuracy of phagocytosis detection compared to traditional assays; (2) evaluate the influence of opsonization, incubation time, and temperature on the phagocytosis ability of rainbow trout (Oncorhynchus mykiss) peripheral blood leukocytes (PBLs). Opsonization increased the PBLs’ phagocytic activity. To evaluate the effects of incubation time and temperature on PBL phagocytosis ability, 30% autologous plasma was used. Leukocytes incubated at 16 °C for 2 h showed a significantly higher (p < 0.05; H = 45.43) percentage of phagocytic cells. This incubation setting also resulted in increased pHR-related fluorescence intensity (p < 0.05; F = 58.39), directly proportional to the number of phagocytosed particles. These findings indicate that opsonization enhances phagocytic ability and capacity, and that a 2 h incubation at 16 °C may be recommended for future large-scale studies aimed at evaluating innate immune function in rainbow trout. Full article

This study examines the effects of climatic variability on bacterial and fungal populations, as well as enzymatic activities innutrient-rich, organic soils that support tea plants (Camellia sinensis L). Conducted from 2016 to 2019 across five district tea estates (TEs) in the Jorhat district of Assam, India, this research investigates the intricate relationships among these parameters. The findings indicate that bacterial and fungal communities exhibit optimal growth within a temperature range of 18 to 30 °C, establishing a critical threshold for their metabolic activity. A significant positive correlation was observed between the abundance of these microbial populations and the corresponding soil enzymatic activities, underscoring the essential role of these robust microbial communities in sustaining vital soil processes. Hierarchical cluster analysis identified two distinct groups of TEs that displayed consistent patterns of microbial behaviour across varying seasonal conditions. Furthermore, principal component analysis demonstrated that the first three principal components accounted for over 80% of the variability observed in the microbial and enzymatic data sets. This research contributes valuable insights into the dynamic interactions between seasonal fluctuations and soil health, highlighting the crucial contributions of bacterial and fungal populations, along with their enzymatic activities, to the complex ecosystem underlying tea cultivation. Full article

Gene therapy is an emerging approach for treating cancer by delivering therapeutic nucleic acids into malignant cells. However, tumor heterogeneity and the tumor microenvironment (TME) undermine the effectiveness of conventional gene therapy, which may lead to off-target activity in normal cells and limit therapeutic efficacy. Tumor-specific promoters (TSPs) provide transcription-level control by activating expression mainly in malignant cells through oncogenic signaling pathways or tumor-associated conditions such as hypoxia and inflammation. Recent work has demonstrated that gene therapy combined with suitable nanodelivery systems, including lipid-based, polymeric and inorganic systems, enables more precise tumor-restricted expression and enhanced antitumor effects. This review summarizes the current landscape of TSP discovery and engineering, and discusses considerations for their integration into emerging nanodelivery systems for cancer treatment. Full article

A 7-week study was conducted to investigate the effects of replacing fish meal (FM) with Spirulina residue meal (SPRM) on the growth, feed utilization, carcass composition, antioxidant ability, liver and intestinal histology of juvenile rainbow trout (Oncorhynchus mykiss) (initial body weight 5.36 ± 0.04 g). Four isonitrogenous (42%) and isolipidic (16%) diets were formulated to replace FM protein with SPRM at 0 (SPRM0), 10% (SPRM10), 20% (SPRM20) and 30% (SPRM30), respectively. Results showed that growth, feed utilization, carcass amino acid profile, serum biochemical indices, antioxidant ability, intestinal and liver histology were not significantly affected by dietary SPRM levels. Whole-body lipid content decreased as dietary SPRM replacement levels increased, and fish fed diet SPRM30 had lower lipid content than that fish fed diet SPRM0 (p < 0.05). Fish fed diet SPRM30 had higher C16:1n-7, C20:3n-6, total saturated fatty acid (SFA) and total fatty acid (TFA) contents in muscle than those fed other diets (p < 0.05), while these fatty acids had no change when FM was substituted with 10% and 20% SPRM (p > 0.05). The muscle C22:6n-3 (DHA) content decreased, but C18:3n-6 and n-6/n-3 polyunsaturated fatty acid (PUFA) ratio increased with increasing SPRM levels, and fish fed diet SPRM30 had significantly lower DHA content and higher n-6/n-3 ratio than the group fed SPRM0 (p < 0.05). The C22:1n-9, C18:2n-6c, C20:4n-6, total n-6 PUFA, and monounsaturated fatty acid (MUFA) content in muscle observed in SPRM30 were similar to the SPRM0 group (p > 0.05), but higher than the SPRM10 and SPRM20 groups (p < 0.05). In conclusion, 30% of FM protein could be replaced by SPRM in diets of juvenile rainbow trout without having a significant negative effect on growth, feed efficiency, antioxidant ability, and structure of liver and intestine, but could reduce DHA content, increase n-6 PUFA and n-6/n-3 PUFA ratio in muscle. Full article

To explore the molecular basis of hypoxia tolerance variation within euteleosts, we compared the hypoxia-inducible factor (HIF) pathways of the highly tolerant Nile tilapia (Oreochromis niloticus) and the hypoxia-sensitive rainbow trout (Oncorhynchus mykiss). Evolutionary analysis revealed that Nile tilapia possesses single copies of Hif-1α and prolyl hydroxylase domain protein 2 (Phd2), whereas rainbow trout retains two and three copies, respectively. The Leu-X-X-Leu-Ala-Pro (LXXLAP) motifs in the oxygen-dependent degradation (ODD) domain of Hif-1α and the interacting loop region of Phd2 are highly conserved, indicating a conserved core mechanism for regulating Hif-1α stability. However, differences in charged residue composition flanking the Phd2 loop (e.g., fewer positively charged residues in Nile tilapia) were identified. Molecular dynamics simulations revealed that the complex formed by Nile tilapia Phd2 and the Hif-1α LXXLAP motif was unstable across physiological temperatures, suggesting potential impairment of the catalytic geometry compatible with hydroxylation and elevated normoxic Hif-1α stability. In contrast, the corresponding complexes in rainbow trout were more stable, particularly at low temperatures. Expression profiling revealed that Nile tilapia tissues, including the heart, maintain higher basal expression of glycolytic genes, may help support energy production during hypoxia. Our findings indicate that a weakened protein interaction and high constitutive expression is predicted to enhance HIF pathway responsiveness, potentially priming vital tissues for glycolytic energy production and may contribute to this species’ hypoxia tolerance. Full article

Lactococcosis has emerged as an economically and ecologically significant disease in aquatic animals worldwide. This study employed multilocus sequence typing (MLST) to investigate the genetic diversity of Lactococcus spp. strains from Brazilian fish species and evaluate their phylogenetic relationships with global isolates to elucidate potential epidemiological connections involving multiple host species and distinct geographic regions. A total of 55 isolates from different laboratories had their DNA extracted, followed by the amplification and sequencing of the internal fragments of seven housekeeping genes (als, atpA, tuf, gapC, gyrB, rpoC and galP). Sequence types (STs) and clonal complexes (CCs) were defined. An unrooted neighbor-joining phylogenetic tree was generated using allele profiles from this study and those previously reported from other aquatic animal species. The isolates comprised 29 STs (11 previously reported, 18 novel ones), which were grouped into species-specific CCs: CC5 (L. formosensis); CC4, CC17, CC62 (L. garvieae); CC24, CC29, CC97 (L. petauri). Considerable genetic divergence was observed, with L. formosensis and L. garvieae forming heterogeneous populations, while L. petauri was more homogeneous. These findings describe the MLST structure of the sampled isolates and should be interpreted as hypothesis-generating rather than population-level estimates of genotype prevalence. Phylogenetics confirmed groupings within the CCs and revealed additional phylogenetic clustering patterns. In conclusion, the Brazilian Lactococcus spp. strains analyzed in this study constitute a genetically diverse population based on their STs. MLST and phylogenetic analysis demonstrated genetic relatedness between the L. garvieae and L. formosensis isolates from this study and those from other aquatic animal species. In contrast, all the STs identified for L. petauri in this study were unrelated to the MLST lineages responsible for outbreaks in Brazilian Nile tilapia (Oreochromis niloticus) and North American rainbow trout (Oncorhynchus mykiss). This suggests that piscine L. petauri populations in the Americas evolved from distinct ancestral origins. Full article

Functional feed additives can improve growth, health, and fillet quality in farmed fish, but their stability during feed processing is limited. This study evaluated the effects of dietary microencapsulated rosemary essential oil (REO), astaxanthin (AX), and butyric acid (BA) on growth, oxidative response, and fillet quality in juvenile rainbow trout (7.9 ± 0.3 g; 90 days). Growth parameters, intestinal and liver health, oxidative status, and fillet pH and color, together with proximate composition and fatty acid profile, were measured. All supplemented groups exhibited higher growth performance compared to controls. Histology and stress/inflammatory markers indicated no adverse effects on tissue health. Regarding fillet quality, REO maintained protein content, AX enhanced lipid content and color stability, and BA promoted a leaner fillet with higher protein deposition. Fillet pH remained more stable in REO and BA groups after frozen storage, suggesting improved product stability. Fatty acid profiles were moderately altered, with REO increasing C18:1n7 and AX enhancing polyunsaturated fatty acids, whereas BA had minimal effects. Plasma antioxidant enzyme activities were lower in supplemented fish, indicating improved redox balance. Overall, microencapsulation preserved the bioactive properties of REO, AX, and BA, supporting their practical use as targeted functional feed additives in rainbow trout aquaculture. Full article