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Clinical overlap between Alzheimer's disease (AD) and limbic-predominant age-related transactive response DNA binding protein 43 (TDP-43) encephalopathy (LATE), combined with the absence of validated in vivo biomarkers, complicates identification of mixed AD/LATE pathology. We labeled individuals along the AD continuum with suspected concomitant LATE using the lower quartile hippocampal volume (HV) cut-off and examined associated atrophy and cognitive profiles. We studied cognitively impaired (CI) Alzheimer's Disease Neuroimaging Initiative (ADNI) participants with T1-magnetic resonance imaging (MRI) and amyloid- and tau-positron emission tomography (PET). Participants were classified into suspected (s) AD+sLATE-, AD-sLATE+, or AD+sLATE+ based on amyloid status and HV quartiles. Medial temporal lobe (MTL) and whole-brain atrophy patterns and cognitive profiles were compared cross-sectionally and longitudinally. Classification was validated in an autopsy cohort. AD+sLATE+ showed greater anterior hippocampal (AH) and amygdala atrophy than AD+sLATE-. AD-sLATE+ and AD+sLATE+ showed greater anterior MTL atrophy and worse memory and language performance. AD+sLATE+ also exhibited faster cognitive decline. A simple HV quartile cut-off may help identify mixed AD/LATE pathology and support clinical trial enrichment. Quartiles of HVs stratify CI individuals. Approach distinguishes suspected AD+sLATE-, AD-sLATE+, and AD+sLATE+ subgroups. The method is simple, scalable, and requires no complex modeling or biomarker panels. It enables practical identification of mixed pathology in clinical settings. It supports trial enrichment by excluding or targeting mixed pathology cases.

With the rapid development of deep buried traffic tunnels, underground space utilization, and global energy resource extraction, the scale of deep underground engineering continues to expand. These trends place increasing demands on understanding the mechanical behavior of rock under high in-situ stress conditions. However, traditional discrete element models, constrained by constant stiffness assumptions, often over-linearize the compaction stage and have difficulty capturing tangent modulus evolution across confining pressures. To address this limitation, this study integrated triaxial test data for multiple lithologies, including granite, slate, and sandstone, and identified a robust exponential relationship between the tangent modulus in the compaction stage and mean stress. Building on this observation, a variable stiffness parallel bond model was developed. The model established a real-time mapping between contact stiffness and contact stress and incorporated a three-state judgment mechanism that enables adaptive stiffness updating. Furthermore, based on the theoretical correlation of stress states, a multi-confining-pressure calibration strategy was introduced. By adopting a method of parameter selection from multiple benchmark conditions combined with interpolation verification, this approach effectively resolves the non-uniqueness issue inherent in micro-macro parameter mapping. Validation using triaxial compression tests on carbonaceous slate over a wide confining pressure range demonstrated that the proposed model can accurately reproduce the morphology of full stress-strain curves. The relative error in peak strength remains within a small margin. The model also systematically captured key pressure-sensitive responses, including the shortening of the compaction stage, peak strength enhancement, and the brittle-ductile transition. Overall, the proposed model provides a high-fidelity numerical tool for predicting rock behavior in deep environments.

Anthropogenic development and land use changes, including habitat loss and fragmentation, have resulted in the decline of many North American birds. Overwintering birds need food resources to meet energetic demands, thermal refugia to reduce energetic costs, and cover to avoid predation. To address how overwintering birds navigate human-dominated landscapes, including the response to a prescribed burn, we used automated and manual radiotelemetry to quantify the overwinter habitat use by Slate-colored Juncos (Junco hyemalis) and American Tree Sparrows (Spizelloides arborea) in southeastern Ohio during the winters of 2023 and 2024. Slate-colored Junco mean home range size was 17.0 ha (95% CI: 15.1–18.9) while American Tree Sparrow mean home range size was 27.1 ha (95% CI: 24.3–30.1). Although habitat use and habitat breadth differed between the two species, both selected edges and used residential areas and roads. Juncos selected or used tall field and forests proportionally, depending on site and year. Slate-colored Juncos used shrublands proportionally but avoided short fields. In contrast, American Tree Sparrows used tall and short fields throughout the winter and we documented a shift in habitat use in response to prescribed fire. Before the prescribed fire, American Tree Sparrows selected shrublands and used forests proportionally, but after the burn, selected burnt fields, used shrublands, and avoided forests. Temporal variation in habitat use by Slate-colored Juncos and American Tree Sparrows highlights the importance in understanding how fluctuation in resource availability due to seasonal variation and management affect the use of habitat patches within the landscape. Public and private landowners can support overwintering granivorous birds by providing tall field, edge, and shrubland habitat while reducing lawn and other mowed fields.

The uranium levels were investigated in 350 drinking water samples from different aquifers (alluvium, quartzite, limestone, slate, phyllite and schist, hornstone breciss, and granite) in northeastern Rajasthan, India. The LED Fluorimeter (model: LF-2a) technique was employed to determine the uranium levels in the drinking water samples. The uranium concentrations range from 0.62 to 128.63, 0.58 to 99.35, 0.79 to 54.40, 0.61 to 41.35, 2.63 to 3.30, 0.57 to 46.24, and 1.01 to 11.98 µg/L, with mean values of 15.95, 9.14, 14.90, 9.70, 2.97, 12.72, and 4.96 µg/L, respectively, for the alluvium, quartzite, limestone, slate, phyllite and schist, hornstone breciss, and granite aquifers. Uranium concentrations across the studied area varied between 0.57 and 128.63 µg/L, with an average of 13.68 µg/L. About 11.14 % of the samples surpassed the World Health Organization's recommended limit (30 µg/L). The radiation dose was calculated by considering the water intake of various age groups, and found infants received the highest calculated dose. On the radiological aspect, two groundwater samples from an alluvium aquifer exceeded the prescribed level (1.67 × 10-4) recommended by the Atomic Energy Regulatory Board of India. The average daily dose of uranium from drinking water ranged from 0.02 to 3.68 µg/kg/day. Approximately 8.3 % of the samples from different aquifers surpassed hazard quotient values of unity and indicated chemical toxicity risks. Uranium levels showed no correlation with physicochemical parameters in all the aquifers.

Redox gradients, often driven by changes in sediment moisture levels in porous, heterogeneous groundwater systems, create dynamic conditions that may promote the production and transport of colloids within natural waters. While much research has focused on the inorganic composition of colloids, the organic composition remains less well understood. Organic matter (OM) in colloids may associate with minerals, complex metal ions, and serve as an electron donor for microbial respiration; therefore, its composition is of high interest. We examined the composition of porewater OM along a redox gradient in a riparian soil located along the Slate River in Crested Butte, Colorado, USA as a function of depth (90, 130, 200, and 350 cm below ground surface). All depths were oxic to suboxic, except 200 cm, where the products of iron and sulfate reduction were observed concomitant with an increase in dissolved and/or colloidal OM, pH, alkalinity, and conductivity. We investigated the composition of porewater using correlated scanning transmission X-ray microscopy and transmission electron microscopy. We observed a change in the OM chemistry from carboxylate-rich at the 200 cm depth (where it was also enmeshed with non-crystalline iron) to phenol- and substituted-aromatic-rich at other depths. Radiocarbon dating revealed carbon in porewater at 200 cm was younger than depths above and below. Soil porewater can flow down into the underlaying gravel bed during baseflow conditions, thus we speculate whether riparian porewater could transport iron- and carboxylate-rich organic colloids into surrounding surface waters through the gravel bed conduit.

The gelling property of fish maw is a key quality indicator, but varietal differences and mechanisms remain unclear. This study investigated the gel properties and underlying mechanisms of three commercial fish maws: Slate cod croaker fish maw (SFM), Basa fish maw (BFM), and Cod fish maw (CFM). Results showed SFM gel formed a dense and uniform network with the highest hardness (16.70 g) and particle size (104.75 nm), whereas BFM gel exhibited inferior texture, and CFM remained fluid. Correlation analysis revealed that the high imino acid content (20.59 g/100 g) of SFMG facilitated robust hydrogen-bonding networks (lowest Amide A wavenumber: 3403 cm-1), thereby stabilizing the triple-helix structure. Conversely, CFMG displayed the highest random coil content (13.94%) and insufficient imino acids (15.82 g/100 g), hindering effective molecular assembly. This research offers a scientific foundation for the quality assessment and targeted processing of fish maw products.

One-component systems (OCSs) integrate sensory and effector functions within a single protein, enabling rapid gene expression changes in response to environmental cues. Here, we characterized a novel putative OCS protein, FG214, from Fimbriimonas ginsengisoli, which drew our attention as a potential redox or O2-regulated helix-turn-helix (HTH)-Per-ARNT-Sim (PAS) transcription factor. Data supporting this included our observation of the FG214 PAS domain binding a hexacoordinate heme b in oxidized conditions and undergoing a slate of redox and ligand-dependent conformational changes, transitioning from a monomer to a homodimer. Spectroscopic and structural data revealed that oxidation stabilizes the likely HTH-PAS intramolecular domain interface, while reduction of the heme iron dissociates the HTH, freeing previously-sequestered homodimerization surfaces. Similar effects were seen by addition of a small molecule ferric heme ligand, as directly visualized with a 1.47 Å crystal structure of an imidazole-bound truncated construct. Using in vitro DNA-binding assays, we identified an artificial promoter sequence and demonstrated ligand-enhanced protein-DNA binding. Finally, we performed proof of concept experiments exploring the ability of FG214 to homodimerize in vivo, setting the stage for a redox or gas sensitive biosensor. Together, these findings define FG214 as a novel heme-binding PAS DNA binding protein and potential transcription factor, complementing known heme-PAS two-component signaling switches.

This study investigates the development and performance of polyolefin-based packaging materials reinforced with industrial mineral residues, specifically slate powder (SP) and bivalve shell powder (BSP). High-density polyethylene (HDPE) and polypropylene (PP) matrices were compounded with these fillers and processed by extrusion blow moulding to produce final prototypes. Thermal analyses (TGA and DSC) showed that incorporating SP and BSP does not compromise the thermal stability of the polymer matrices and increases stiffness in the filled formulations. Accelerated ageing (QUV, 200 h) revealed distinct photo-oxidative behaviours. PP and PP + BSP (30%) exhibited increased fragility and moderate colour changes, whereas PP + SP (10%) retained flexibility, indicating a partial protective effect of SP. HDPE-based formulations showed higher intrinsic UV resistance, with HDPE + BSP (30%) displaying excellent colour stability. Tensile tests before and after QUV exposure confirmed that fillers increase stiffness with limited influence on tensile strength. Air permeability results indicated that neat PP and HDPE were below the detection limit. At the same time, filled formulations exhibited measurable permeability, suggesting that filler incorporation may influence gas transport through interfacial effects. Overall, the results show that SP and BSP act as reinforcing additives and can modify functional properties such as stiffness and ageing resistance. However, their influence on barrier performance depends on the formulation and permeation mechanism.

The general public in the Himalayan region is exposed to considerable radiation from indoor radon, thoron, and their decay products. The estimation of natural radiation, source apportionment, and concentrations of its decay products is vital for population health risk assessment. In this study, the inhalation dose and seasonal variability of indoor radon, thoron, and their progeny were investigated in the sub-mountainous Dhauladhar region of the north-west (NW) Himalaya, India. A total of 51 dwellings from 17 villages, such as cemented (H1), slate + mud (H2), and cemented + tin roofs (H3), were randomly selected for indoor radon, thoron, and their progeny measurements. The annual indoor average radon and thoron concentrations measured in H1 houses were 74.8-53.0 Bq/m3, respectively. Whereas, in H2 and H3, it showed an average of 90.6, 67.8, 69.8 and 48.4 Bq/m3, respectively. The correlation between indoor radon and thoron was found to be 0.77. The inhalation dose in the H1 was found to be 0.69-0.35 mSv/y, respectively. Similarly, for the H2 and H3, the values found to be 0.80, 0.43,0.65 and 0.32 mSv/y, respectively. The result suggests that the high indoor radon, thoron, and their progeny were recorded during winter seasons and radon and thoron levels in H2 houses was found slightly higher compared to the H1 and H2 houses, mainly depending on the type of dwelling, ventilation rate and cold environmental conditions.

Plastic streams dominated by polyethylene (PE) including PE HD/MD (High Density/Medium Density) and PE LD/LLD (Low Density/Linear Low Density), polypropylene (PP), and polyvinyl chloride (PVC) across Europe demand a design framework that links synthesis with end of life reactivity, supporting circular economic goals and European Union waste management targets. This work integrates polymerization derived chain architecture and depolymerization mechanisms to guide selective valorization of commercial plastic wastes in the European context. Catalytic topologies such as Bronsted or Lewis acidity, framework aluminum siting, micro and mesoporosity, initiators, and strategies for process termination are evaluated under relevant variables including temperature, heating rate, vapor residence time, and pressure as encountered in industrial practice throughout Europe. The analysis demonstrates that polymer chain architecture constrains reaction pathways and attainable product profiles, while additives, catalyst residues, and contaminants in real waste streams can shift radical populations and observed selectivity under otherwise similar operating windows. For example, strong Bronsted acidity and shape selective micropores favor the formation of C2 to C4 olefins and Benzene, Toluene, and Xylene (BTX) aromatics, while weaker acidity and hierarchical porosity help preserve chain length, resulting in paraffinic oils and waxes. Increasing mesopore content shortens contact times and limits undesired secondary cracking. The use of suitable initiators lowers the energy threshold and broadens processing options, whereas diffusion management and surface passivation help reduce catalyst deactivation. In the case of PVC, continuous hydrogen chloride removal and the use of basic or redox co catalysts or ionic liquids reduce the dehydrochlorination temperature and improve fraction purity. Staged dechlorination followed by subsequent residue cracking is essential to obtain high quality output and prevent the release of harmful by products within European Union approved processes. Framing process design as a sequence that connects chain architecture, degradation chemistry, and operating windows supports mechanistically informed selection of catalysts, severity, and residence time, while recognizing that reported selectivity varies strongly with reactor configuration and feed heterogeneity and that focused comparative studies are required to validate quantitative structure to selectivity links. In European post consumer sorting chains, PS and PC are frequently handled as separate fractions or appear in residues with distinct processing routes, therefore they are not included in the polymer set analyzed here. Polystyrene and polycarbonate are outside the scope of this review because they are commonly handled as separate fractions and are typically optimized toward different product slates than the gas, oil, and wax focused pathways emphasized here.

Light stimuli-responsive structural color change is ubiquitous in animals, serving functions such as camouflage and social signaling. The striped pattern of zebrafish changes from slate-blue in dark-adapted conditions to bright-blue in light-adapted conditions. Our study reveals that this reversible color variation originates from the synergistic movement of the dual-layer guanine reflector. This reflector is composed of inclined crystal arrays in S-iridophores and horizontal crystal arrays in L-iridophores. The classical "Venetian blind" model, which relies on a single-layer photonic crystal array and emphasizes the influence of individual structural parameters like the tilting angle, failed to predict structural color change in the zebrafish skin. However, this color variation could be well described by our "Dragon Boat" model, which considers the synergistic movement of the dual-layer photonic crystal ultrastructure. Key findings in our study show that the reflectance peak position is controlled by crystal tilting angles and spacings, while its intensity depends on interlayer distance. These new insights offer a framework for designing biocompatible optical materials with tunable light properties.

Opioid agonists such as morphine and fentanyl exert analgesic effects by binding and activating the μ-opioid receptor (μOR), yet agonism of the μOR causes a slate of serious side effects. μOR-mediated addiction and respiratory depression are the major causes of the current opioid overdose crisis, largely driven by the explosion in illicit use of fentanyl, a potent opioid receptor full agonist. Given these serious side effects (and high resulting societal cost), molecules that act as analgesics with distinct mechanisms of action are of great interest. Positive allosteric modulators (PAMs) of the μOR have the potential to avoid many off-target side effects of conventional opioid orthosteric agonists by enhancing the signaling properties of natural opioid peptide systems. We used a DNA-encoded chemical library screening approach to selectively discover active-state-specific μOR PAMs. Two out of 3 selected prospective PAMs displayed the anticipated enhancement in agonist activity. The most effective of these compounds enhanced the activity of all orthosteric opioid agonists tested, including the native opioid peptide met-enkephalin. Little is known about the underlying dynamic basis of allosteric modulation of Family A GPCRs like the μOR. To that end, we used single-molecule fluorescence resonance energy transfer experiments to detail the impact that our novel μOR PAM has on the dynamic activation behavior of a key region on the intracellular face of the receptor. Our results here provide both a new chemical scaffold that acts as a μOR PAM and detailed pharmacological and dynamic insights into its mechanism of action.

Safety assessment of a deep geological repository is essential to ensure the long-term isolation of spent nuclear fuel and protection of the environment. Uranium migration in groundwater is a key factor in evaluating the safety of the spent nuclear fuel disposal, and uranium mobility is significantly influenced by redox conditions. However, quantifying the effects of redox changes at the field-scale remains challenging. This study investigates uranium migration under changing redox conditions using a tracer test and reactive transport modeling. The study site consists of uranium-bearing black slate and has weakly oxidizing groundwater conditions (1.62 mg/L DO). Strongly oxidizing conditions were induced by injecting DO-saturated groundwater (10.16 mg/L DO) during the tracer test. Uranium migration during the tracer test was quantified using a reactive transport model (RTM) that couples a discrete fracture-matrix (DFM) model implemented in COMSOL Multiphysics with the geochemical code PhreeqcRM. The tracer test showed that uranium mobility increased under shifting redox conditions, with the maximum uranium concentration rising by 85.2% and the cumulative mass increasing by 66.0%. The RTM results indicate that desorption primarily contributes to the enhancement of uranium mobility, and that the oxidative dissolution rate of UO2 varies by up to six-fold depending on redox conditions. These findings highlight that redox changes can increase uranium mobility and the need to consider redox evolutions in the safety assessment of spent nuclear fuel disposal.