Search Results (12,623)

Members of the genus Rhizobium are best known for nitrogen-fixing symbioses with legumes, yet their diversity and evolutionary roles in non-legume hosts remain poorly explored, particularly in arid ecosystems. We report the isolation and characterization of strain AGC32, an endophytic bacterium obtained from surface-sterilized roots of the desert medicinal plant Peganum harmala collected in Moroccan drylands. Phylogenomic analyses placed AGC32 within the genus Rhizobium but clearly distinct from described species, with average nucleotide identity values below 96% and digital DNA–DNA hybridization values below 70%, supporting its designation as a novel species for which the name Rhizobium moroccans sp. nov. is proposed. Comparative genomics revealed extensive structural genome rearrangements relative to its closest sequenced relative, Rhizobium deserti, indicating a divergent evolutionary trajectory. The high-quality draft genome encodes metabolic pathways associated with adaptation to nutrient limitation and environmental stress, including complete allantoin utilization, polyphosphate metabolism, organic acid assimilation, and multiple systems involved in oxidative and osmotic stress tolerance. Phenotypic assays corroborated these genomic predictions, demonstrating the ability to metabolize diverse organic acids and carbohydrates and to express multiple plant growth–promoting traits, including nitrogen fixation and the solubilization of phosphorus, potassium, and silicon. Collectively, these findings expand the ecological and evolutionary diversity of Rhizobium, demonstrate its capacity to associate with non-legume medicinal plants in extreme environments, and highlight desert ecosystems as reservoirs of previously unrecognized microbial diversity with potential applications in sustainable agriculture in arid regions. Full article

The environmental impacts from fossil fuel use have accelerated the global transition to sustainable energy sources. Hydrogen has become a promising alternative due to its high energy density and clean combustion. However, hydrogen production streams are frequently contaminated with methane, which needs efficient, durable, and cost-effective purification technologies such as pressure swing adsorption (PSA). The present study provides a comparative evaluation of biomass-derived activated carbons and a commercial activated carbon for hydrogen–methane separation. High-surface-area activated carbons were synthesized from sustainable pine and birch precursors via chemical activation using potassium hydroxide (KOH, impregnation ratio 3:1) at 800 °C. Their dynamic adsorption performance was systematically assessed in a fixed-bed setup under a PSA system operating at pressures of 25, 35, and 50 bar, using a of hydrogen–methane gas mixture, where methane feed concentrations ranging from 10 to 30 vol%. This work focuses on the behavior of the adsorbent material and does not constitute a complete PSA process evaluation. The biomass-derived activated carbons showed well-developed textural characteristics, with specific surface areas up to 1416 m² g⁻¹, which exceeded that of the commercial reference material (1023 m² g⁻¹). This improved pore structure was reflected in their adsorption behavior at an operating pressure of 50 bar; the birch-derived carbon achieved a methane uptake of 10.5 mol kg⁻¹, more than twice the capacity of 5.30 mol kg⁻¹ measured for the commercial adsorbent. Beyond initial adsorption capacity, the study emphasizes operational durability and reusability. Cyclic adsorption–desorption experiments, supported by Raman spectroscopy, revealed pronounced structural changes in the commercial activated carbon under repeated operational stress, as indicated by an increase in the I_D/I_G ratio from 1.08 to 1.24. In contrast, the biomass-derived activated carbons preserved their morphological integrity and adsorption efficiency over successive cycles. These findings demonstrate that pine- and birch-derived activated carbons are not only sustainable alternatives but also operationally stable adsorbents capable for hydrogen purification processes. Full article

The concurrent occurrence of COVID-19 and the 2024 Noto Peninsula earthquake resulted in a “compound disaster” in Japan. This retrospective study, spanning 11 years (2015–2025), examines the impact of these crises on trends in cardiovascular surgery, focusing on infective endocarditis (IE). A total of 2444 surgical cases were analyzed across three distinct periods: pre-pandemic (2015–2019), pandemic (2020–2023), and compound disasters (2024). While overall surgical volumes exhibited fluctuations, there was a notable increase in the number of interventions for IE and renal failure in 2024. Additionally, the 2024 IE cohort revealed a significant epidemiological shift, characterized by a younger median age (56 years compared to 70 years pre-pandemic), absence of pre-existing valvular disease, and a marked rise in blood culture-negative endocarditis (BCNE), which accounted for 83.3% of IE cases. In 2025, the number of surgical IE cases decreased to zero, highlighting the acute nature of the peak in 2024. These findings illustrate that compound disasters can disrupt cardiovascular surgical trends and underscore the susceptibility of IE to compromised healthcare access and environmental stress. The development of resilient diagnostic pathways is essential for managing complex public health emergencies. Full article

Chronic exposure to artificial light at night (ALAN) is increasingly recognized as an environmental risk factor that disrupts circadian regulation of endocrine and metabolic systems. In this study, we investigated the effects of extreme ALAN on oxidative stress and gut microbiota composition in mice using two complementary experiments. In Experiment 1, adult female mice were maintained under either as a standard 12 h light/12 h dark cycle (12 h group) or continuous 24 h light exposure (24 h group) throughout pregnancy and lactation. In Experiment 2, the offspring from the 12 h group were maintained under the same photoperiod, whereas offspring from the 24 h group were divided into a 12 h light/12 h dark group or a continuous 24 h light group, with treatments initiated on postnatal day 19 and continued until 2 months of age. For all 12 h groups, light exposure occurred from 8:00 to 20:00. Compared with dams in the 12 h group, dams exposed to continuous light exhibited significantly increased catalase activity, while their offspring maintained under the 12 h photoperiod showed elevated glutathione levels. No significant changes were detected in immune organ indices. These results suggest that extreme ALAN modulates antioxidant defenses, potentially reflecting adaptive responses to oxidative stress. Moreover, offspring exposed early to extreme ALAN showed significantly reduced gut microbial α-diversity, accompanied by decreased abundances of Firmicutes, Bacteroidota, Campylobacterota, and Desulfobacterota, and an increase in Proteobacteria. Notably, Verrucomicrobiota and Akkermansia failed to recover following photoperiod normalization, indicating persistent microbiota dysbiosis. Overall, these findings demonstrate that extreme ALAN induces oxidative stress and long-lasting alterations in gut microbiota composition, highlighting potential health risks associated with night-time light pollution. Full article

Environmental exposure to particulate matter, including PM_2.5 and engineered nanomaterials, is a major global health concern. Although acute toxic effects have been widely documented, new evidence suggests that the retained particle burden arising from incomplete clearance, tissue retention, and redistribution plays a key role in long-term health outcomes. This review synthesizes knowledge on particle accumulation at multiple biological levels. It examines how particles are retained in pulmonary and lymphoid tissues, their uptake by immune cells, and their sequestration within organelles, particularly the endo-lysosomal system. The mechanisms by which lysosomal dysfunction can cause mitochondrial stress, redox and metabolic disturbances, and impaired autophagy are also discussed. These disruptions can alter the status of immune cells and disturb immune homeostasis. This review also examines how immune perturbation from accumulation may contribute to chronic lung diseases. Understanding these mechanisms explains the persistent health effects associated with low-dose exposure and supports more effective risk assessment and prevention. Full article

Cadmium (Cd) is a major environmental pollutant due to its high mobility and persistence in soils, facilitating entry into the food chain and threatening ecosystems and human health. However, the mechanisms that enable Salix species, well adapted for Cd remediation, to both tolerate and accumulate Cd remain elusive. Here, two Salix genotypes with contrasting Cd tolerance were examined under control and Cd stress using integrated physiological, transcriptomic, and metabolomic analyses of roots and leaves. The Cd-tolerant genotype (Salix suchowensis P294) maintained biomass under Cd stress, whereas the Cd-sensitive genotype (Salix sinopurpurea × Salix integra P646) showed a ~17% reduction. P294 accumulated more Cd in its stems (132.76 mg kg⁻¹) and leaves (122.25 mg kg⁻¹) than P646 (93.54 and 56.24 mg kg⁻¹). Transcriptomics responses were stronger in roots, with 896 DEGs in P294 and 462 in P646, enriched in nitrogen metabolism, phenylpropanoid biosynthesis, and metal transport, whereas only 167 and 176 DEGs were detected in leaves for P294 and P646, respectively. Metabolomics revealed more altered metabolites in roots (125 in P294, 89 in P646), mainly organic acids, amino acids, and flavonoids, compared with leaves (46 and 66). RT-qPCR validated the root-specific upregulation of key detoxification and transport genes (ABCA7, PRX72, GSTU1, GSTU4, ZIP1). These results reveal a root-centered regulatory network underlying Cd accumulation and tolerance, integrating detoxification, redox homeostasis, and structural reinforcement, as well as providing valuable targets for genetic improvement of phytoremediation efficiency. Full article

Intensive aquaculture induces severe environmental stress and disease susceptibility in Pacific white shrimp (Litopenaeus vannamei). Cannabidiol (CBD) offers significant potential as a bioactive stress-mitigating additive. This study evaluated the effects of dietary CBD supplementation (0, 10, 20, 40, and 80 mg/kg) on the growth, intestinal microecology, and stress tolerance of juvenile L. vannamei over an 8-week feeding trial, followed by a combined chronic ammonia and acute hypoxia challenge. Moderate CBD supplementation (10–40 mg/kg) significantly promoted growth, minimized feed conversion ratios, and enriched muscle eicosapentaenoic (EPA) and docosahexaenoic acids (DHA). Furthermore, CBD restructured the intestinal microbiota by suppressing opportunistic pathogens and enriching beneficial taxa. Under combined stress, moderate CBD prolonged the median lethal time (LT₅₀) by up-regulating hypoxia-inducible factor 1-alpha (hif-1α) and heat shock protein 70 (hsp70) transcription and boosting systemic antioxidant capacity to neutralize lipid peroxidation. Conversely, the highest dose (80 mg/kg) induced metabolic exhaustion and hepatopancreatic toxicity, evidenced by drastically elevated serum transaminases and diminished stress tolerance. Conclusively, dietary CBD exerts a classic biphasic effect in L. vannamei. Inclusion at 10–40 mg/kg safely promotes the best comprehensive effects on growth, immune homeostasis, and environmental resilience within the concentration range tested in this study, whereas excessive administration provokes severe metabolic burden, highlighting the critical need for strict dosage regulation. Full article

Microbial bio-inoculants have been proposed as management tools to enhance crop performance under variable environmental conditions; however, their effectiveness is often influenced by site-specific factors. This study evaluated the effects of bio-inoculation on seed germination and seedling vigor of pea under osmotic stress induced by polyethylene glycol (PEG 6000), and its interaction with two fertilization levels (75% and 100% of the recommended dose) under field conditions in the Amazonas region of Peru. Under laboratory conditions, germination percentage remained high across all treatments (93.3–100%) and was not affected by bio-inoculation or osmotic potential; however, osmotic stress altered germination dynamics, increasing mean germination time from 1.85–2.09 days at 0 MPa to 2.26–2.43 days at −0.8 MPa, while germination synchrony and seedling vigor decreased as stress increased. The seedling vigor index reached maximum values at −0.2 MPa (4.47–5.29) and declined at −0.8 MPa (1.50–2.00), and multivariate analyses showed that variation in germination responses was mainly associated with germination timing and vigor rather than seed viability. Under field conditions, no significant effects of fertilization level, microbial bio-inoculation, or their interaction were detected on agronomic traits or yield, although variability between locations was observed; plant height ranged from 38.5–46.3 cm in Lamud and from 100.6–108.3 cm in Molinopampa, while grain yield varied from 698–1846 kg/ha and 8771–9919 kg/ha, respectively. Overall, environmental conditions exerted a stronger influence than microbial bio-inoculation on germination dynamics and field productivity, while the findings provide practical guidance for improving pea production with bio-inoculants and optimized fertilization. Full article

Salicylic acid (SA) is a key endogenous regulator involved in plant defense responses to biotic and abiotic stresses. The increasing resistance of pathogens to chemical plant protection products and growing environmental restrictions have intensified the search for alternative strategies to enhance plant health and stress tolerance. Among these strategies, the induction of natural defense mechanisms, in which SA plays a central signaling role, has gained particular attention. This review summarizes current knowledge on the role of SA in shaping plant resistance to environmental factors. The fundamental mechanisms of plant defense, including innate immunity, induced systemic resistance (ISR), and systemic acquired resistance (SAR), are discussed, with emphasis on the signaling function of SA and its interaction with other phytohormones, especially jasmonic acid and ethylene. The role of SA in regulating physiological processes associated with stress tolerance, such as antioxidant system activity, photosynthesis, plant growth, and senescence, is highlighted. The review of research results indicates that appropriately selected doses and timing of SA treatments can enhance resistance to selected pathogens and improve plant tolerance to adverse environmental conditions. However, treatment effectiveness depends on multiple factors, particularly SA concentration and plant–pathogen interactions. Salicylic acid is a promising component of integrated and sustainable plant protection strategies. Further research, especially under field conditions, is necessary to optimize its practical use and fully determine its potential in modern agriculture. Full article

Energy use remains central to Colombia’s economic growth, yet its composition shapes the scale and direction of environmental outcomes. This study investigates how coal, oil, and hydroelectricity influence ecological degradation within the context of economic growth. The study applies cross-quantilogram and bootstrap Fourier Granger causality techniques to capture directional dependence and predictive causality across different quantiles, respectively. The findings show that the relationships are heterogeneous rather than uniform across the distribution. Economic growth exhibits a predominantly negative dependence on ecological footprint, suggesting that higher output is associated with lower ecological pressure under several environmental states. Hydroelectricity also shows a largely negative dependence, indicating its general contribution to environmental sustainability, although this effect weakens under extreme conditions. By contrast, the effects of coal and oil are more conditional and vary across quantiles, reflecting the complex role of fossil fuels in Colombia’s environmental dynamics. The bootstrap Fourier Granger causality results further reveal that causality is not constant across the distribution, but emerges only at specific quantiles. The central policy implication from this result lies in adopting an adaptive environmental strategy in which preventive measures dominate under low degradation, green-supportive policies are emphasized under moderate degradation, and stronger corrective interventions are implemented under high ecological stress. Full article

Hybrid supramolecular–nanocomposite hydrogels based on polyethylene glycol (PEG), β-cyclodextrin–adamantane host–guest interactions, and silica nanoparticles represent an important class of hierarchical soft materials with tunable viscoelastic and transport properties. This review critically analyzes recent progress in cyclodextrin–silica hybrid PEG hydrogels, focusing on the mechanistic coupling between stiffness, stress relaxation, and molecular transport arising from the interplay between reversible supramolecular crosslinks and nanoparticle-induced confinement effects. Particular attention is given to how host–guest exchange kinetics regulate dynamic bond rearrangement and affinity-mediated retention of hydrophobic cargo, while silica nanoparticles enhance mechanical reinforcement and modify diffusion pathways through tortuosity and interfacial polymer–particle interactions. The analysis highlights how nanoparticle size, loading level, and surface functionalization influence relaxation spectra and network topology, as well as how environmental stimuli may affect supramolecular bond stability and overall material performance. Comparison with alternative inorganic fillers and mesoporous silica architectures further clarifies the specific advantages of silica in achieving balanced mechanical stability and controlled transport behavior. Overall, current evidence indicates that hybrid CD–silica networks enable partial decoupling of stiffness, relaxation dynamics, and diffusion, although complete independence remains constrained by fundamental polymer physics relationships. These insights support the development of predictive structure–property frameworks for advanced biomedical and controlled release applications. Full article

In underground coal mining, the gear of a shearer’s rocker arm endures extreme stress and environmental fluctuations. Failures in this vital component can pose serious safety hazards, cause prolonged operational downtime, and result in significant financial losses. Therefore, accurate gear fault diagnosis is crucial. However, conventional diagnostic methods often struggle with limited feature extraction and poor performance when dealing with non-stationary, noisy signals typical of this environment. To address these challenges, a hybrid model consisting of Convolutional Neural Network (CNN), Long Short-Term Memory (LSTM) network, and Markov Transition Model (MTM) is proposed. In this framework, the CNN is used to extract both global and local features related to gear fault. A time-distributed feature extractor is then integrated with the LSTM to capture the temporal progression of these features, aiding in effective modeling of fault evolution over time. Finally, the MTM further refines classification by incorporating probabilistic state transition between fault conditions, thereby improving diagnostic stability and robustness under noise. Experimental validation was done using vibration data from the Taizhong Coal Machinery rocker arm test platform and gear data from Southeast University and achieved up to 99.79% accuracy. These results show this proposed method outperformed other advanced diagnostic methods, offering dependable fault diagnosis and strong noise resistance even under extreme noise conditions of −5 dB SNR. Full article

Ross 308 chickens were randomly divided into 2 groups of 600 birds each: a control group (C) and an experimental group (M). The birds were reared for 42 days in accordance with the flock management guidelines. Group M was exposed to music for 2 h/day and for 30 min before slaughter (~70 dB). After slaughter, the carcasses were cooled, and after 24 h, the pectoral muscles were collected for further physicochemical analyses. The study results revealed a lower value of drip loss in the pectoral muscles of the chickens from group M than in those from group C (p ≤ 0.01). Moreover, the muscles from group M chickens had higher pH values at 15 min, 1 h, and 12 h (p ≤ 0.01) and also at 4 h (p ≤ 0.05) post-mortem. Pectoral muscles of group M chickens also showed lower L* and b* color parameters (p ≤ 0.01), collagen content (p ≤ 0.05), and GSH concentration (p ≤ 0.01), compared to control birds. Exposure to ambient relaxation music in the scheme used in the study may be an effective form of environmental enrichment for broiler chickens, leading to physicochemical changes in their pectoral muscles consistent with potentially lower pre-slaughter stress. Full article

Automated pig-welfare monitoring needs scalable, non-invasive signals that work across ages and individuals. A key methodological contribution of this study is the use of subject-wise validation, which ensures generalization to unseen animals and prevents inflated accuracy caused by growth-related and individual ‘voice’ differences. Vocalizations can help, but growth and individual “voice” differences can confound distress patterns and overstate accuracy without subject-wise validation. In our study, we explicitly accounted for individual variability by including animal identity as a random effect in mixed models and by using grouped cross-validation, where models were tested only on pigs not seen during training. This approach ensures that the reported accuracy reflects generalization across different individuals rather than memorization of specific vocal signatures. We analyzed 2221 vocal samples from 40 pigs (20 males, 20 females) recorded across four growth phases (farrowing, nursery, growing, finishing) under six conditions (pain, hunger, thirst, cold stress, heat stress, normal). Acoustic features extracted in Praat included energy, duration, intensity, pitch, and formants (F1–F4). Using blockwise variance decomposition, we quantified contributions of distress exposure, growth phase, and sex, and estimated the additional variance explained by animal identity. Distress exposure dominated intensity and spectral traits, particularly Formant 2, whereas the growth phase produced systematic shifts in duration and pitch. Animal identity added a modest but consistent increment in explained variance (~+0.02–0.03 R² beyond sex, phase, and distress). For prediction, we used 5-fold cross-validation grouped by animal. A Random Forest achieved a modest balanced accuracy of 0.609 and macro-F1 of 0.597; pain was most separable (recall 0.825), while other states showed moderate recall, indicating overlap. These results support hierarchical acoustic encoding of distress and establish a benchmark for precision welfare monitoring. Furthermore, they highlight that resolving complex physiological overlaps, such as heat stress and resource competition, requires a shift from unimodal acoustic models to multimodal Precision Livestock Farming (PLF) systems that integrate bioacoustics with continuous environmental and behavioral data streams. Full article

Bangia fuscopurpurea is a marine alga with significant commercial value. Although a high-light adapted species, the productivity of its commercial cultivation is frequently limited by environmental light attenuation, resulting in the algae operating under energy-limiting, sub-saturating conditions. This study investigated its physiological responses and antioxidant defense mechanisms across a sub-saturating light gradient (20, 40, and 80 µmol photons m⁻² s⁻¹). We employed exogenous ascorbic acid (AsA) supplementation to evaluate the dynamic response of the ascorbate-glutathione (AsA-GSH) cycle. Without AsA supplementation, the 40 µmol photons m⁻² s⁻¹ condition supported redox homeostasis and the highest soluble protein accumulation. In contrast, the lowest irradiance (20 µmol photons m⁻² s⁻¹) restricted physiological performance. At 80 µmol photons m⁻² s⁻¹, which remained below the light saturation point, the algae experienced oxidative stress, indicated by elevated lipid peroxidation and hydrogen peroxide levels. The efficacy of exogenous AsA depended on these energy states. Under the highest tested irradiance (80 µmol photons m⁻² s⁻¹), AsA reduced malondialdehyde (MDA) and maintained electron transport capacity, but these effects were accompanied by a significant degradation of photosynthetic pigments. These findings imply an altered partitioning of cellular reducing power, where the demand for AsA regeneration might limit the resources available for biosynthetic pathways. The study highlights that antioxidant efficacy is constrained by the cellular energy availability, which limits simultaneous stress mitigation and growth in light-limited aquaculture environments. Full article