Search Results (5,642)

Understanding how spiral structures influence the chemical evolution of the Galactic disc remains a key issue in Galactic archaeology. Recent advances in two-dimensional chemical evolution modeling allow us to account for the impact of multiple spiral arm patterns, each characterized by different pattern speeds, on the redistribution of elements throughout the Galaxy. In this work, we explore the influence of multi-pattern spiral arms on the radial abundance gradients of heavy elements in the Galactic disc. We focus on a scenario in which, during the most recent stage of evolution, corotation spans the entire disc. Our results indicate that the observed dispersion in the abundance gradients of O, Fe, Eu, and Ba, as traced by Cepheids, can be successfully reproduced if all galactocentric radii have effectively acted as corotation regions over the past 1–3 Gyr. We also note that such an extended phase has previously been identified as necessary to explain the azimuthal abundance variations reported in Gaia DR3 and Gaia-ESO survey data along local and inner spiral arms. Full article

Geodiversity, particularly topographical gradients, significantly influences ecosystem function by creating heterogeneous environmental conditions. This study examined how local-scale microtopography and litter bag perforation affected leaf litter decomposition rates in a humid-temperate secondary forest. We categorized microtopography into ridge, valley, southwest slope, and northeast slope, with relative height differences of around 20 m. Using the litter bag method comparing non-perforated (1 mm mesh) and perforated (with 6 mm holes) bags, we measured leaf litter mass loss and moisture content of Quercus serrata over 6 and 12 months. While microtopography caused only slight differences in leaf litter moisture content, it significantly influenced decomposition rates. Leaf litter mass loss was lower in valley microtopography compared to the southwest slope and ridge microtopography. We infer that topographical differences in unmeasured microclimatic factors, such as solar radiation and soil temperature, may have potentially driven these spatial variations in decomposition. Furthermore, because the litter bag perforation did not significantly promote further mass loss, our results suggest that baseline decomposition driven by organisms capable of passing through the 1 mm mesh (e.g., microbes and meso/microfauna) might have been sufficiently high in this environment. These findings highlight that local-scale microtopographical differences enhance the spatial heterogeneity of leaf litter decomposition in forest ecosystems. Full article

In this note, we describe compatible Leibniz algebras and present several of their properties. Our aim is to present a comprehensive classification of non-Lie nilpotent compatible Leibniz algebras in low dimensions. By using the full classification of non-Lie nilpotent Leibniz algebras over the complex field of dimensions two, three, and four, in this note, our aim is to provide the classification of non-Lie nilpotent compatible Leibniz algebras over the complex field of dimensions two, three, and four. Consequently, we show that there is no isomorphism class in dimension two, there are 5 isomorphism classes in dimension three, and there are 134 isomorphism classes in dimension four. Full article

Background/Objectives: Closely related species provide an opportunity to study evolutionary processes that underpin new species formation. Speciation driven by adaptation to distinct environments, such as adaptation to high and low elevation in Senecio aethnensis and Senecio chrysanthemifolius, respectively, on Mount Etna, Sicily, is particularly informative about the interplay between natural selection and ongoing interspecific gene flow. Methods: In this study, we analysed the relative contribution of adaptive introgression and local adaptation in these Senecio species. We used genome resequencing with short read sequence data, and analysed patterns of polymorphism within and between the two Senecio species. Results: Genome-wide scans for selection identified numerous putative selective sweep regions, many of which overlap with selected regions detected in cline-based analysis in the same system. Our results indicate the prevalence of local over introgressive sweeps, consistent with local adaptation to contrasting environments driving divergence of these species. However, many putative introgressive sweeps were also detected, possibly driven by shared selective forces, such as adaptation to volcanic soils and disease resistance, as indicated by GO terms linked to defence responses for some of the introgressive sweeps. Conclusions: The results suggest that even though the two species are now adapted to different environments, introgression has facilitated their adaptation by sharing adaptive alleles between species, which is likely an important factor for adaptation in closely related species. Full article

This study evaluated a non-invasive nose-mounted accelerometer for automated detection of chewing strokes in dairy cows. Data were collected from 15 Holstein Friesians and validated against manual video annotations. Chewing strokes were identified using a peak detection algorithm applied to smoothed acceleration data. Two algorithm versions were analyzed: a raw version and a cleaned version that excluded a five-second interval during regurgitation, where no physiological chewing occurs. The cleaned version showed higher agreement with the reference method (Intraclass Correlation Coefficient [ICC] = 0.91; 95% Confidence Interval [CI]: 0.77–0.96) and lower error metrics (Mean Absolute Error [MAE]: 3.67; Root Mean Square Error [RMSE]: 4.72; Mean Absolute Percentage Error [MAPE]: 5.64%) compared to the raw version (ICC = 0.67; MAE: 10.00; RMSE: 11.48; MAPE: 15.27%). Both methods demonstrated that reliable detection of chewing activity is feasible using this sensor system. Automated chewing stroke detection may contribute to the assessment of rumen function, feeding behaviour, and animal welfare and may support future precision livestock farming applications by providing objective information on chewing activity. Full article

Glutamine-Fructose-6-Phosphate Transaminase 1 (GFPT1), the rate-limiting enzyme of the hexosamine biosynthetic pathway (HBP), provides the UDP-N-acetylglucosamine (UDP-GlcNAc) required for protein glycosylation. Biallelic mutations in GFPT1 cause congenital myasthenic syndromes (GFPT1-CMS), yet the molecular mechanisms linking impaired glycosylation to skeletal muscle dysfunction remain incompletely understood. Here, we combine cellular models of inducible Gfpt1 knockdown and a skeletal muscle-specific Gfpt1 knockout mouse (Gfpt1^Tm1d/Tm1d) with whole-cell proteomics, immunoblot studies and secretomics to define glycosylation-dependent defects in intracellular trafficking, ER stress signaling and autophagy. Global proteomic profiling of Gfpt1-deficient myoblasts revealed marked downregulation of protein trafficking pathways and impaired secretion of key muscle cargo proteins, including serglycin (Srgn). Loss of GFPT1 reduced both high-molecular-weight glycosylated serglycin and its core protein, accompanied by intracellular retention and decreased secretion. These trafficking defects coincide with robust activation of the unfolded protein response (UPR), evidenced by increased Xbp1 expression and accumulation of spliced Xbp1s across pharmacologic, cellular, and mouse models of GFPT1 deficiency. Converging evidence from proteomics, immunoblotting, and immunofluorescence demonstrated impaired autophagy, including increased LC3-II accumulation, elevated p62/Sqstm1 levels, and enhanced p62-positive puncta in both Gfpt1-deficient C2C12 myoblasts and skeletal muscle. Soluble/insoluble fractionation further confirmed p62 accumulation, indicating defective autophagic flux and buildup of aggregated cargo. Together, these findings identify a glycosylation-dependent failure in protein trafficking that triggers ER stress, UPR activation, and autophagy impairment in Gfpt1-deficient skeletal muscle. This mechanistic cascade provides a unifying explanation for muscle pathology in GFPT1-CMS and suggests that restoring glycosylation or improving proteostasis may represent viable therapeutic approaches. Full article

Large carnivore conservation (LCC) presents complex social–ecological challenges in environmental governance, yet limited research has examined how institutional design influences conservation outcomes. This study compares community-based conservation (CBC) in India’s tiger conservation with collaborative governance regimes (CGR) in Germany’s wolf conservation. We conducted a policy-network analysis using Net-Map interviews with formal policy actors involved in LCC governance (India: n = 21. Germany: n = 15). Network structures were analyzed across four tie categories—information-sharing, instructions, influence, and advice—while structural and perceived power distributions were compared across governance levels. Results show that information-sharing dominated governance interactions in both countries, whereas advice ties remained weak. India’s CBC exhibited ties concentrated largely within the forest department administration. Despite stronger local stakeholder integration, social justice framing affected direct inclusivity in policy decisions. Germany’s CGR demonstrated fragmented policy centers with most power concentrated at the German federal state levels. Environmental justice framing allows stronger influence by powerful non-state actors but alienates local stakeholders from policy decisions. Discrepancies between structural and perceived power were evident in both systems, highlighting participation–power disconnects within conservation governance. The findings suggest that effective and sustainable LCC governance requires stronger cross level coordination, institutionalized scientific advice mechanisms, and meaningful inclusion of local stakeholders in policy processes for sustainable LCC. Full article

The Azores are characterized by intense volcanic activity, creating unique environments such as fumarole sites, where geothermal gases and high temperatures drive distinct chemical and biological processes. To investigate small-scale heterogeneity within such a site, six visually distinct samples were collected within a 30 cm radius at an active fumarole on São Miguel Island. The samples were analyzed for elemental and mineralogical composition, bacterial lipid biomarkers (PLFAs), and microbial community structure using a novel DNA separation technique to specifically target the living microbiome. Despite mineralogical similarities across all samples—predominantly composed of alunite, alkali-feldspar, and quartz—significant microbial heterogeneity was observed. Both PLFA and bacterial iDNA analyses revealed distinct microbial communities associated with specific conditions indicated by the specific colors: red and brown samples were dominated by Proteobacteria and Actinobacteriota, yellow and green by Thermoplasmatota and Actinobacteriota, and white and gray by Crenarchaeota. Interestingly, the gray samples exhibited a broader microbial composition, sharing some taxa with all other samples. These striking color variations are likely driven by differences in both specific mineral composition and microbial pigmentation, reflecting localized biogeochemical processes. Our findings demonstrate that extreme microbial heterogeneity can occur over remarkably small spatial scales within fumarolic systems, underscoring the complex interplay between chemical and biological factors in these dynamic volcanic habitats. Full article

The spin of an electron is an intrinsic quantum property that cannot be explained using classical mechanics. Nevertheless, it is possible to conceive semiclassical systems with internal degrees of freedom that exhibit spin-like properties. Building on the analysis of phase modulation by elliptical gears and kinematically equivalent antiparallelogram linkages, we present a novel semiclassical model of Zitterbewegung, a rapid oscillatory motion closely connected with spin. The kinematical analog is based on including the internal rotation of the linkage represented in spacetime. The system’s dynamics is related to two-center electron models, which describe the constant momentum of the center of mass and the lightlike oscillation of the center of charge at twice the Compton frequency for a particle at rest. A two-dimensional extension provides an intuitive illustration of topological spin properties and can be used to calculate the spin and magnetic moment of an electron. Full article

Ship diesel engines are a significant source of aerosol particles and gaseous pollutants for the marine atmospheric boundary layer (MABL). To assess the environmental impact of maritime transport on the MABL, it is important to understand how aerosol particles are transported, dispersed and transformed in ship exhaust plumes. The dynamics of aerosol particle size distributions, ranging from 5 nm to 4 µm at a height of 1.5 m above sea level, were measured on board a boat behind cruising ships in German waters in the Baltic Sea. Exhaust plumes were measured at ages of 2–60 s at distances of 20–600 m from cruising ships; the number concentration of 5–340 nm particles increased about a hundred times in comparison with background levels, while the mass of supermicron particles increased only by 1–6% compared to background levels. Changes in aerosol particle number size distributions were mainly driven by plume expansion. However, in plumes aged 6–16 s at distances of 50–150 m, a sudden drop in number concentration by 30% for 20 nm particles was observed. Their scavenging followed by fast sedimentation with sea spray microdroplets generated by ship movement is a possible explanation for this. A significant reduction in the residence time of nanoparticles may imply extensive environmental consequences. Full article

This paper investigates whether transcendent worldviews—those oriented toward a beyond—decline while immanent worldviews—those oriented toward this world—increase. We draw on an inventory spanning positions from theism and deism to naturalism and existentialism, administered seven times in West Germany (1982–2023) and six times in East Germany (1992–2023). In West Germany, existentialist worldviews ranked first, followed by naturalist, theist, and deist ones. While existentialist worldviews remained stable, transcendent worldviews declined and immanent ones grew, producing a substantial and growing advantage for immanent over transcendent orientations. In East Germany, existentialist and naturalist worldviews were markedly dominant, well above transcendent ones throughout the observation period. Both remained stable, while transcendent worldviews increased only minimally, leaving the gap largely intact. To test whether these period effects persist under controls, we employ OLS regressions with robust standard errors, accounting for cohort, age, church attendance and belonging, community size, parenthood, work engagement, education, and gender. In West Germany, transcendent worldviews declined and immanent ones increased non-monotonically. In East Germany, the pattern reversed: transcendent worldviews increased and immanent ones decreased non-monotonically. While mean levels do not differ significantly between the two regions, the direction and structure of effects do. The discussion addresses why transcendent worldviews are better explained than immanent ones, and what accounts for the divergent trajectories between East and West Germany. Full article

Background/Objectives: Numerous studies have investigated the responses of the gastrointestinal tract to tastants, particularly in specialized enteroendocrine and other chemosensory cells. However, many of these investigations used various taste stimuli often at high concentrations or relied on immortalized cell lines or heterogeneous cell populations, which can limit their physiological relevance and reproducibility. To establish a stable, physiologically representative model system for consistently investigating gut epithelial responses to tastants, our study developed 3D murine intestinal organoids (MIOs). Methods: Murine intestinal organoids were generated from isolated intestinal crypts and cultured under defined conditions to maintain epithelial differentiation. Organoids were stimulated with selected nutrients and tastants, and downstream signaling responses were assessed using hormone secretion assays. Results: The 3D MIO culture system was successfully established, providing a robust in vitro platform for studying extraoral bitter sensing and release of the enteroendocrine hormone cholecystokinin. Moreover, 5 mM denatonium benzoate and 30 mM L-glutamic acid specifically induced cholecystokinin secretion in MIOs, whereas other bitter or non-bitter stimuli did not. Conclusions: Murine intestinal organoids provide a stable model for studying nutrient- and tastant-evoked signaling in the gut. This approach enables precise investigation of underlying mechanisms and may advance our understanding of gut chemosensation and metabolic regulation. Full article

Climate change is intensifying soil salinization, posing a major threat to crop establishment and productivity, particularly in arid and semi-arid regions. Barley (Hordeum vulgare L.), one of the most salt-tolerant cereals, offers valuable genetic resources for improving salinity resilience at early growth stages. This study exploited the genetic diversity of the Nested Association Mapping (NAM) population Halle Exotic Barley-25 (HEB-25) to dissect salinity tolerance during germination and seedling developmental stages. First, the HEB-25 parental lines (25 wild barley genotypes and cv. Barke) were evaluated under salinity treatment to identify contrasting responses. Based on this screening, four HEB families (01, 04, 09, and 22) were selected out of 25 HEB families for detailed phenotypic and genomic analysis. Seeds of the selected HEB families were subjected to 40% seawater salinity stress and control treatments to assess germination percentage and seedling traits, including shoot length, root length, fresh weight (FW), dry weight (DW), DW/FW ratio, root–shoot ratio, and salt tolerance index (STI). Substantial variation was observed among families for all measured traits under salinity stress. STI values enabled clear differentiation among families: Family 01 exhibited the most consistent overall tolerance profile, Family 22 showed the strongest sensitivity in biomass traits, and Family 04 displayed a trait-specific response with sensitivity at the family-mean level but exceptional within-family diversity, harboring some of the highest individual TI values across the population. A genome-wide association study was conducted using 32,995 SNP markers. A total of 27 significant SNPs were identified, corresponding to 20 quantitative trait loci (QTLs). Of these, 12 QTLs were detected under control conditions, 16 under seawater treatment, and 21 based on tolerance indices, indicating both constitutive and stress-responsive genetic effects. Gene annotation within these regions revealed approximately 23 candidate genes associated with abiotic stress tolerance, including genes involved in ion transport, osmotic adjustment, kinases and stress signaling pathways. HEB_22_003, HEB_04_087, and HEB_01_013 represent the most promising genotypes for salinity breeding. These findings highlight the effectiveness of combining precise phenotyping with high-resolution genomic analysis in the HEB-25 population to uncover the genetic architecture of salinity tolerance at early developmental stages. We identified 20 salinity-responsive QTLs, including five major-effect loci on chromosomes 2H, 4H, 5H, and 7H that consistently explained the largest share of phenotypic variation. These loci co-localized with candidate genes linked to ion homeostasis, Ca²⁺-mediated signaling, protein glycosylation, epigenetic regulation, and root system plasticity, revealing key mechanisms underlying early-stage salt adaptation in barley. The strong and contrasting responses of Family 01 and Family 04 provide an excellent genetic framework for functional validation of tolerance alleles. Collectively, these genomic resources establish a robust foundation for QTL pyramiding, marker-assisted breeding, and the development of climate-resilient barley cultivars for saline agroecosystems. Full article

Introduction: Coastal fishes can adapt to water warming and hypoxia; however, acute tolerance does not necessarily predict longer-term performance and survival. This may be especially important in sedentary, site-faithful species with limited escape to escape increasingly unfavorable habitats. We assessed the climate-related stress responses of the Lusitanian toadfish, Halobatrachus didactylus, a benthic estuarine fish from the Northeast Atlantic, to water warming and hypoxia. Objectives: We aimed to determine the aerobic energy budget, thermal limits (CTmax), and critical oxygen tension (Pcrit), as well as blood indicators of metabolism, altered physiology and systemic stress, as proxies for whole-organism homeostatic state, thereby informing future ecophysiological assessments and bioindicator development in a context of environmental change. Methodology: We determined standard, routine, and maximum metabolic rates; aerobic scope; and critical thermal maximum (CTmax) and critical oxygen (Pcrit) thresholds on a set of 134 individuals ranging from 12 to 160 g in weight. On a different set of individuals (n = 48; 76.3 ± 2.6 g; 16.1 ± 0.18 cm), we simulated 30 days of seasonal scenarios combining low and high temperature with normoxia or hypoxia, followed by integrated metabolic, hematological, biochemical, and multivariate analyses. Results: Acute trials showed high short-term resilience: H. didactylus had an exceptionally low standard metabolic rate and routine metabolic rate, high CTmax (34.82 ± 0.66 °C), and strong hypoxia tolerance (Pcrit 0.59–1.97 mg O₂ L⁻¹), although smaller individuals were more sensitive. After 30 days, however, warming more than doubled standard and routine metabolic rates, while warm hypoxia reduced metabolic output relative to warm normoxia, consistent with metabolic depression under compounded stressors. This treatment also showed shifts in glucose, liver mass, red blood cell count, and hematocrit, identifying warm, oxygen-poor water as the most physiologically costly scenario for this species. Conclusions: Together, these results show that high acute tolerance does not guarantee resilience to climate change. In sedentary fishes, survival may depend less on surviving extremes than on maintaining energetic balance, oxygen transport capacity, and physiological homeostasis in increasingly warm, oxygen-poor coastal habitats. Full article