Search Results (711)

Under the background of global climate change, lichens as a staple fallback food source for the endangered Yunnan snub-nosed monkey (Rhinopithecus bieti) exert a critical influence on the survival of Yunnan snub-nosed monkey populations through their distribution dynamics. This study focused on the contiguous habitats of the Yunnan snub-nosed monkey in the southern Hengduan Mountains. By species distribution models (SDMs) and landscape pattern analysis, we investigated the changes in suitable habitats of lichens under four Representative Concentration Pathway (RCP) scenarios and their implications for the habitat utilization of the Yunnan snub-nosed monkey until 2050. The results indicate that the current suitable habitat for lichen spans approximately 16,821.96 km², with highly suitable habitats predominantly located in Deqin County and Weixi County. Altitude and vegetation type emerged as primary factors influencing lichen distribution. The overlap rate of suitable habitats between lichens and the Yunnan snub-nosed monkey is 72.24%. Furthermore, the Yunnan snub-nosed monkey exhibits a preference for selecting habitats characterized by the largest patch index (LPI) of lichen distribution. By 2050, the suitable habitat for lichen is projected to marginally increase in the southern Hengduan Mountains, particularly under the RCP 6.0 scenario, by 22.20% compared to the current expansion. However, both the suitable habitat and the LPI of lichen face potential decline within the habitat of the Yunnan snub-nosed monkey. Therefore, we recommend conducting a quantitative investigation into the correlation between the actual productivity of lichen radiata and the population dynamics of Yunnan snub-nosed monkey as a priority. This research will offer a more precise scientific foundation for conservation decision-making for Yunnan snub-nosed monkey. Full article

The glyoxalase pathway intermediate S-d-lactoylglutathione was recently implicated in protein post-translational modifications in animal systems. Here, we examined the spontaneous modification of the Arabidopsis thaliana cytosolic glyceraldehyde-3-phosphate dehydrogenase C1 (GAPC1) by this compound. Incubation of GAPC1 with S-d-lactoylglutathione resulted in the inhibition of enzyme activity. The inhibitory effect was concentration dependent and increased at alkaline pHs. Furthermore, the inhibition of GAPC1 by S-d-lactoylglutathione was favored by oxidative conditions and reversed by reduction with dithiothreitol. Analyses of the S-d-lactoylglutathione-treated protein by nanoLC-MS/MS revealed S-glutathionylation of its two Cys residues and N-lactoylation of six Lys residues. Protein structure predictions showed that the double S-glutathionylation is accommodated by the GAPC1 catalytic pocket, which likely explains enzyme inhibition. N-lactoylated sites overlap partially with previously reported N-acetylated sites at the surface of the GAPC1 tetramer. The efficiency of cytosolic glutaredoxin and thioredoxin isoforms was tested for reversing the S-d-lactoylglutathione-induced modification. In these assays, recovery of GAPC1 activity after inhibition by S-d-lactoylglutathione treatment was used as indicator of efficiency. The results show that both types of redoxins were able to reverse inhibition. We propose a model describing the mechanisms involved in the two types of post-translational modifications found on GAPC1 following exposure to S-d-lactoylglutathione. The possible involvement of these findings for the control over glycolytic metabolism is discussed. Full article

Aluminum alloys under long-term service or repetitive stress are prone to small fatigue cracks (FCs) with arbitrary orientations, necessitating eddy current probes with focused magnetic fields and directional selectivity for reliable detection. This study presents a flexible printed circuit board (FPCB) probe with a double-layer planar excitation coil and a double-layer differential receiving coil. The excitation coil employs a reverse-wound design to enhance magnetic field directionality and focusing, while the differential receiving coil improves sensitivity and suppresses common-mode noise. The probe is optimized by adjusting the excitation coil overlap and the excitation–receiving coil angles to maximize eddy current concentration and detection signals. Finite element simulations and experiments confirm the system’s effectiveness in detecting surface cracks of varying sizes and orientations. To further characterize these defects, two time-domain features are extracted: the peak-to-peak value ($\Delta$P), reflecting amplitude variations associated with defect size and orientation, and the signal width ($\Delta$W), primarily correlated with defect angle. However, substantial overlap in their value ranges for defects with different parameters means that these features alone cannot identify which specific parameter has changed, making prior defect classification using a Transformer-based approach necessary for accurate quantitative analysis. The proposed method demonstrates reliable performance and clear interpretability for defect evaluation in aluminum components. Full article

We present a tunable diode-laser absorption spectroscopy (TDLAS) system operating at 1.5711 µm for CO₂ gas concentration measurements. The system can operate in either a traditional direct-mode (dTDLAS) sawtooth wavelength scan or a recently demonstrated wavelength-toggled single laser differential-absorption lidar (WTSL-DIAL) mode using precompensated current pulses. The use of such precompensated pulses offsets the slow thermal constants of the diode laser, leading to fast toggling between ON and OFF-resonance wavelengths. A short measurement time is indeed pivotal for atmospheric sensing, where ambient factors, such as turbulence or mechanical vibrations, would otherwise deteriorate sensitivity, precision and accuracy. Having a system able to operate in both modes allows us to benchmark the novel experimental procedure against the well-established dTDLAS method. The theory behind the new WTSL-DIAL method is also expanded to include the periodicity of the current modulation, fundamental for the calculation of the OFF-resonance wavelength. A two-detector scheme is chosen to suppress the influence of laser intensity fluctuations in time (1/f noise), and its performance is eventually benchmarked against a one-detector approach. The main difference between dTDLAS and WTSL-DIAL, in terms of signal processing, lies in the fact that while the former requires time-consuming data processing, which limits the maximum update rate of the instrument, the latter allows for computationally simpler and faster concentration readings. To compare other performance metrics, the update rate was kept at 2 kHz for both methods. To analyze the dTDLAS data, a four-parameter Lorentzian fit was performed, where the fitting function comprised the six main neighboring absorption lines centered around 1.5711 µm. Similarly, the spectral overlap between the same lines was considered when analyzing the WTSL-DIAL data in real time. Our investigation shows that, for the studied time intervals, the WTSL-DIAL approach is 3.65 ± 0.04 times more precise; however, the dTDLAS-derived CO₂ concentration measurements are less subject to systematic errors, in particular pressure-induced ones. The experimental results are accompanied by a thorough explanation and discussion of the models used, as well as their advantages and limitations. Full article

Virus-associated hepatocellular carcinoma (HCC) remains a major global health burden despite effective antiviral therapies. Chronic infection with hepatitis B (HBV), hepatitis C (HCV), and hepatitis D (HDV) promotes malignant transformation through overlapping pathways of fibrosis, immune dysregulation, and microenvironmental remodeling. YKL-40, a glycoprotein secreted by hepatic stellate cells, hepatocytes under stress, macrophages, and endothelial cells, has emerged as a marker that reflects stromal activation rather than direct hepatocyte injury. Its expression is reinforced by profibrotic and angiogenic circuits, and circulating concentrations correlate with advanced fibrosis, residual risk after viral suppression, and oncologic outcomes. This review synthesizes current evidence on YKL-40 across HBV, HCV, and HDV cohorts, with emphasis on its role in bridging molecular mechanisms to clinical applications. We examine its utility in non-invasive fibrosis assessment, longitudinal monitoring after antiviral therapy, and prognostic modeling in HCC. Particular attention is given to its potential in the liver transplant pathway, where YKL-40 may refine eligibility beyond morphology, inform bridging therapy response, and predict post-transplant recurrence or graft fibrosis. Remaining challenges include its lack of disease specificity, assay variability, and limited multicenter validation. Future integration of YKL-40 into multimarker, algorithm-based frameworks could enable risk-adaptive strategies that align surveillance and transplant decisions with the evolving biology of virus-associated liver disease. Full article

The accurate assessment and management of Blue Mackerel (Scomber australasicus) and Chub Mackerel (Scomber japonicus) resources in the high seas of the Northwest Pacific are constrained by the persistent issue of data misreporting in catch records, which arises from their high morphological similarity. This study integrates fishery logbooks and field sampling data from Chinese purse seine fleets (2014–2023), along with key oceanographic factors—six of which were finally selected after correlation analysis. We introduce, for the first time, a Zero-One Inflated Beta Model (ZOIBM) to analyze the spatiotemporal distribution of the relative abundance of these two mackerel species. Furthermore, a Generalized Additive Model (GAM) was employed to reveal the environmental mechanisms driving their niche differentiation. The results show that the ZOIBM demonstrates excellent performance (R² = 0.63, RMSE = 0.305), effectively quantifying the proportional composition of the two species in mixed catches. Spatially, high-abundance areas of Blue Mackerel were concentrated within 35–44° N, 145–160° E, with its proportion decreasing at higher latitudes. In contrast, Chub Mackerel exhibited an opposite latitudinal pattern, with its high-abundance areas covering a broader latitudinal range (35–47.5° N). The analysis of environmental drivers indicated that SST was the most critical factor for differentiation, while Chla and VO further amplified the divergence in resource utilization strategies between the species. From 2014 to 2023, the distribution centroids of both mackerel species showed significant northward and eastward shifts, and their spatial overlap has been continuously increasing. This research provides a methodological reference for the fine-scale assessment of co-occurring fish resources and offers a scientific basis for the sustainable management of the North Pacific mackerel fishery. Full article

Obesity, type 2 diabetes mellitus (T2DM), and cardiovascular diseases (CVDs) represent major global health burdens with overlapping pathophysiological mechanisms, including chronic low-grade inflammation, oxidative stress, and gut microbiota dysbiosis. Galectins, a family of β-galactoside-binding lectins, have been implicated in immune regulation, inflammation, and tissue remodeling. Among them, Galectin-4 (Gal-4), primarily expressed in the gastrointestinal tract, has emerged as a potential biomarker due to its roles in epithelial integrity, inflammatory signaling, and metabolic regulation. Despite its established involvement in cancer and inflammatory disease, the relevance of Gal-4 in cardiometabolic disorders remains poorly defined. A comprehensive literature search was conducted via the PubMed and ScienceDirect databases. The association between Gal-4 and obesity has been reported, indicating that elevated Gal-4 levels correlate with obesity, but primarily in individuals with diabetes. Circulating Gal-4 concentrations are consistently elevated in diabetic populations. In CVD, elevated Gal-4 levels are associated with ischemic heart disease, heart failure, aortic stenosis, carotid atherosclerosis, and adverse outcomes following myocardial infarction and stroke. Furthermore, prospective studies link Gal-4 to increased risk of cardiovascular events and mortality, underscoring its potential prognostic relevance. Available evidence regarding the mechanistic role of Gal-4 in the pathogenesis of obesity, diabetes, and cardiovascular disease remains limited; therefore, future studies should address whether Gal-4 actively contributes to cardiometabolic dysfunction or only reflects secondary inflammatory or fibrotic processes. Elucidating the biological functions of Gal-4 may provide insight into its utility in diagnostics and support the development of novel therapeutic strategies for cardiometabolic disorders. Full article

The subsurface chlorophyll maximum (SCM) is widely observed in the ocean and is often associated with phytoplankton biomass, where aggregated phytoplankton leads to increased chlorophyll concentrations in the water column. Pycnocline facilitates biomass accumulation by trapping nutrients and providing favorable physical conditions. However, comprehensive studies remain lacking regarding the coupling mechanism between pycnocline and SCM and the extent to which this relationship affects SCM dynamics through biomass accumulation. To investigate the seasonal coupling between the pycnocline and SCM, we established a linear regression model and quantified their relationship using a coupling coefficient, which describes the seasonal transition of SCM in terms of biomass accumulation. The results were validated using BGC-Argo data. Our findings reveal that SCM and the pycnocline consistently exhibit periodic coupling patterns within seasonal cycles, and in the Indian Ocean and the northwestern Pacific, SCM is predominantly biomass-driven during seasons with strong pycnocline coupling (the coupling coefficient ranges between 0.5 and 0.7). In contrast, this coupling weakens significantly in oligotrophic regions (the coupling coefficient remained below 0.3 in more than half of the months studied), where SCM no longer exhibits a clear overlap with peaks in particulate backscattering (BBP). Full article

Contrast-induced encephalopathy (CIE) is a rare complication after percutaneous coronary intervention (PCI) that mimics intracranial hemorrhage (ICH). Its computed tomography (CT) findings (cortical contrast enhancement, sulci effacement) overlap with cerebrovascular conditions (e.g., cerebral infarction, subarachnoid hemorrhage). Dual-energy CT (DECT) differentiates blood/calcification from iodinated contrast medium (CM) extravasation via material decomposition, contributing to the accurate diagnosis of CIE. We report a CIE case highlighting DECT’s value. A 74-year-old woman underwent PCI. 50 min post-PCI, she had moderate headache (Numeric Rating Scale 4), dizziness, non-projectile vomiting (no seizures); vital signs were stable, no focal deficits, mannitol ineffective. Non-contrast CT demonstrated a left parietal 75 Hounsfield unit (HU) high-attenuation lesion, indistinguishable from acute intracerebral hemorrhage. Conventional non-contrast CT revealed a high-attenuation lesion (75 HU) in the left parietal lobe—indistinguishable from ICH. DECT clarified the diagnosis: virtual non-contrast maps showed CM extravasation, iodine concentration maps confirmed focal CM accumulation, and effective atomic number maps improved lesion visualization. The patient’s headache resolved within 5 h; follow-up non-contrast CT at 24 h showed complete disappearance of the lesion. She resumed clopidogrel, discharged day 3 without sequelae. This case underscores DECT’s role in distinguishing CIE (transient CM, normal neuro exam) from ICH (persistent hemorrhage), guiding safe post-PCI antiplatelet therapy. Full article

Accurate wind measurements in the mesosphere and lower thermosphere (MLT) region are essential for climate modeling, satellite drag estimation, and space weather prediction. This study presents a comprehensive comparison and correlation analysis of the zonal and meridional wind observations from co-located meteor radar and medium-frequency (MF) radar systems in Kunming (102.1°E, 24.2°N), China, in the year 2022. Both zonal and meridional wind components were analyzed within the overlapping altitude range of 70–100 km. Statistical distributions of the wind speeds from both radars followed a near-Gaussian pattern concentrated within ±100 m/s, indicating good consistency. A joint dataset was constructed for the 78–100 km range, where over 2000 h of concurrent observations were available. The strongest correlation between the wind speed measurements of the two radars was ~0.6, which occurred near 82–84 km. Seasonal analysis further indicated better consistency in the winter and spring months, while the summer months exhibited reduced correlations, especially for zonal wind measurements. Systematic biases between the two instruments were also identified, with minimal intercept offsets observed from April to October. This study is valuable in the development of high-quality, long-term MLT wind field datasets for atmospheric research and numerical model validation. Full article

Urban blue-green infrastructure (UBGI) has been recognized as an effective nature-based solution (NbS) for mitigating urban overheating through temperature reduction. However, there is a paucity of research examining whether UBGI spatial configurations align with the geographical distribution of the heat exposure risks of urban residents. This study focuses on this research gap, employing a population-weighted algorithm to conduct a refined assessment of the blue-green spaces exposure and heat exposure risks of urban residents. Then, the heat exposure risk was conceptualized as the demand for cooling services, with exposure to blue-green spaces serving as the supply. A comprehensive assessment was finally conducted of the supply–demand relationship and coupling coordination level for cooling services in central Wuhan. The following findings were revealed: (1) Both heat exposure risks and blue-green exposure demonstrate distinct “west high–east low” spatial gradients. It is evident that extreme high/high-risk zones, which encompass 17.1% of the study area, house 74.49% of the permanent population; (2) A substantial and pervasive positive correlation exists between UGBI exposure and the heat exposure risk. “High-demand–high-supply” areas (14.90% coverage) concentrate in urban cores, overlapping with 61.25% high-risk populations, while 0.29% of zones show “high-demand–low-supply” mismatches, revealing concentrated but ineffective UGBI distribution; (3) A pervasive supply–demand imbalance is evident, with 90.64% of regions exhibiting an unacceptable coupling type range (0 < D ≤ 0.4) and a mere 1.39% attaining an acceptable range (0.6 < D ≤ 1). These findings underscore the inadequacy of prevailing urban blue-green infrastructure configurations in addressing heat exposure risks. The construction of cities with greater heat resilience necessitates the implementation of multidimensional strategies aimed at risk mitigation. Full article

Despite increasing concerns over recurrent phosphorus (P) pollution, the Ju River—a small tributary of the Yangtze River—has received limited scientific attention. To correct this, the present study integrates field-based observations with the Hydrological Simulation Program—FORTRAN (HSPF) model to comprehensively assess the conjunct effects of urban expansion and changing precipitation patterns on watershed hydrology and phosphorus dynamics at the small-catchment scale. A total of five urban expansion scenarios and three precipitation enhancement scenarios were simulated to capture both seasonal and event-driven variations in daily discharge and total phosphorus (TP) concentrations. The model was calibrated and validated using in situ water quality data, ensuring high reliability of the simulations. The results indicate that agricultural non-point sources are the primary contributor to total phosphorus (TP) loads. During the overlapping period of intensive farming and heavy rainfall (June–July), TP concentrations more than doubled compared to other months, with these two months accounting for over 70% of the annual TP load. Urban expansion significantly amplified hydrological extremes, increasing peak discharge by up to 224% under extreme rainfall, thereby intensifying flood risks. Although increased precipitation diluted TP concentrations, it simultaneously accelerated overall phosphorus export. This study offers a novel modeling–monitoring framework tailored for small watersheds and provides critical insights into how land use transitions and climate change jointly reshape nutrient cycling. The findings support the development of targeted, scenario-based strategies to mitigate eutrophication risks in vulnerable river systems. Full article

Protected areas (PAs) are increasingly exposed to anthropogenic pressures under global change scenarios, with surrounding land subdivision and land use/land cover change (LULCC) dynamics often undermining their conservation goals and intensifying demand for basic services such as water availability. This study analyzed the buffer zone around Cerro Castillo National Park in Chilean Patagonia to assess the evolution of rural private properties, considering their subdivision, LULCC, and legal water demand dynamics. Using cadastral records, Landsat 8 imagery, and official water rights databases, we quantified property subdivision and analyzed LULCC and water rights distribution patterns through spatial overlap analysis. Results indicate a nearly fourfold increase in subdivisions between 2011 and 2023, with 304 properties divided into 3237 units occupying 43.7% of the private land area. LULCC analysis revealed a net recovery of native forest (+10%) alongside notable increases in urban coverage (+152%) and exotic plantations (+245%). Legal water demand almost doubled, with 68% of consumptive rights concentrated in subdivided properties. These findings highlight property subdivision as an important factor influencing socioecological change in the territories that surround PAs. We argue that subdivision dynamics can serve as an early indicator for anticipating land use pressures and can complement integrated landscape-scale planning, consistent with the transformative change approaches advocated by international biodiversity frameworks. Full article

Phase instability that develops during thermal conversion of heavy oils and bitumen limits the extent of conversion in processes such as visbreaking. It was postulated that aromatic species with conjugated unsaturated systems extending beyond the aromatic rings likely contributed to reactions leading to phase instability, fouling, and coking. Many fluorophores have such conjugated π-electron systems. Three case studies were presented where products from thermal conversion were analyzed by fluorescence spectroscopy: (i) Cold Lake bitumen converted at 150–300 °C; (ii) asphaltenes depleted and enriched Athabasca bitumen converted at 380 °C; and (iii) Athabasca bitumen converted at 400 °C and 0.5–4.0 MPa. It was found that the fluorescence intensity of bitumen increased on thermal conversion. Fluorescence intensity increased in relation to reaction time for conversion at 150–300 °C, but it had a weak relationship with temperature. At 380 and 400 °C, this monotonic relationship was no longer apparent. There was no relationship with refractive index. Despite some overlap in fluorescence intensity values, 400 °C converted products obtained at 2.5–4.0 MPa had lower fluorescence intensity than products obtained at 0.5–2.0 MPa. Tentative explanations were offered for these observations. The change in fluorescence intensity with operating conditions and nature of the feed was consistent with the expected free radical concentration associated with the operating conditions and extent of hydrogen transfer. Although the study did not provide proof for the relationship between the fluorescence intensity and the concentration of aromatic species with conjugated unsaturated systems, the experimental observations were congruent with it. Full article

The Hengduan Mountains, a global biodiversity hotspot, harbor numerous endemic plant species shaped by complex topography and microclimatic variation. However, increasing habitat fragmentation due to human activities threatens narrowly distributed species such as Cycas panzhihuaensis. To investigate its habitat suitability and inform conservation, we applied the MaxEnt model, Geodetector, and Zonation to predict potential distribution, identify key environmental drivers, and delineate priority conservation areas. Our results show that only 18.36% of the region constitutes suitable and highly fragmented habitat, primarily concentrated along the dry–hot valleys of the Jinsha and Yalong Rivers, and it is shrinking while shifting southward and southeastward under climate change. Elevation emerged as the dominant driver (q = 0.45), with strong interaction effects among topographic, climatic, soil, and anthropogenic factors, highlighting the role of environmental synergies in shaping habitat heterogeneity. Priority conservation areas covered 32% of suitable habitat and overlapped only 6.17% with existing protected areas, indicating a spatial conservation gap. These findings emphasize the need to incorporate microhabitat heterogeneity and environmental interactions in conservation planning and support the adoption of micro-reserve strategies to complement existing reserves. Our study provides a practical framework for protecting vulnerable montane species and offers insights into plant distribution dynamics in topographically complex regions. Full article