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The accurate prediction of the large-strain thermomechanical response of shape memory polymer (SMP) beams is challenging because geometric nonlinearities must be coupled with temperature-dependent viscoelastic and viscoplastic mechanisms, including plastic softening. This study develops a semi-analytical framework for the large-strain pure bending of thermoviscoplastic SMP beams. The formulation combines finite-deformation bending kinematics with the thermoviscoplastic constitutive model of Zeng et al., while a mapping-based fitting strategy is introduced to approximate the through-thickness distribution of the viscous mechanical stretches. The resulting stress field is obtained by enforcing radial equilibrium in polar coordinates and satisfying the traction-free inner and outer surfaces. The formulation is implemented in MATLAB R2026a and independently verified against a three-dimensional ABAQUS/Explicit model incorporating the same constitutive equations through a user-defined VUMAT. Shape recovery, bending-force recovery, stress distributions, deformation fields, and mesh sensitivity are investigated for two SMP material parameter sets. The semi-analytical and finite element predictions show close agreement throughout the thermomechanical cycles. For example, at the end of the relaxation stage, the predicted inner radii are 27.27 mm and 27.26 mm for the semi-analytical and finite element approaches, respectively, corresponding to a difference of approximately 0.04%. The results demonstrate that the proposed formulation provides an efficient alternative for analyzing large-strain SMP bending while retaining the essential path-dependent thermoviscoplastic behavior. Full article

Fangshankou turquoise, hosted by the Lower Cambrian phosphorus–vanadium–uranium black-shale ore system of Dunhuang, NW China, has been reported to contain anomalously high Na, Fe and Si, but the mineralogical origin of these anomalies is unknown. Micro-Raman screening combined with SEM-EDS, powder and single-crystal XRD, EPMA and LA-ICP-MS on 27 specimens shows that turquoise is intergrown at the 10–50 μm scale with cyrilovite (17.7–22.4 wt% FeO, 2.6–4.7 wt% Na₂O), a poorly crystalline unnamed NaAl phosphate phase (4.9–11.1 wt% Na₂O; diagnostic Raman band at 992 cm⁻¹), fluorapatite, collinsite, alunite, jarosite, goethite, phengite and chabazite-Na. Raman-screened turquoise contains only 2.2–6.5 wt% FeO and ≤0.8 wt% Na₂O; the higher values obtained on unscreened material arise from analytical volumes that intersect these Na- and Fe-rich phosphates, not from unusual substitution in turquoise, whose structure offers no site for Na. Screened turquoise inherits the Li–Cr–V–U signature of its black-shale host (615–1357 ppm Cr, up to 65 ppm U), whereas the origin of its moderate Si remains unresolved. Chabazite-Na in post-turquoise fractures records a late Si–Na–K-rich fluid stage. The Na-rich phosphate assemblage, not reported from other Chinese turquoise deposits, is itself a potential provenance indicator, and the results show that provenance criteria for microcrystalline turquoise must rest on phase-resolved rather than bulk analyses. Full article

Continuous monitoring of land-use/land-cover (LULC) change is essential in the Al-Ahsa Oasis, an arid region characterized by a sensitive and fragile environment. This study is the first to integrate vegetation, climate, and land-use frameworks by combining vegetation indicators, climatic variables, and LULC trajectory classification over a 41-year period (1985–2025). Data from three Landsat sensors (Landsat 5-TM, 7-ETM+, and 8-OLI) were processed to derive vegetation indicators and an LULC trajectory classification, while ERA5-Land and CHIRPS data provided surface temperature and rainfall information, respectively. LULC trajectory classification was implemented using a random forest classifier, generating six LULC trajectory classes: stable barren, stable urban, stable water, urban expansion, transition lands, and stable vegetation. Pearson correlation analysis was used to assess the relationships between the vegetation indicators (normalized difference vegetation index [NDVI] and soil-adjusted vegetation index [SAVI]) and climatic variables (temperature and rainfall) at different time lags (0–3 years) and after detrending the time series. The detrending analysis showed no statistically significant associations between the vegetation indicators (NDVI and SAVI) and the climatic variables (temperature and rainfall) across the four examined lags, whereas the original, non-detrended time series showed positive associations that were mainly attributable to long-term trends rather than to interannual climate–vegetation covariation. The accuracy of LULC trajectory classification was high, with an overall accuracy of 0.939 and a kappa coefficient of 0.924, indicating robust mapping performance. Overall vegetation cover improved over the study period. The degradation occurred in the central part of the oasis (stable urban, urban expansion, and stable water classes, accounting for 4.506%, 5.179%, and 41.773% of each trajectory class, respectively), whereas the recovery was observed in the northern, southern, and eastern parts (stable vegetation and transition lands, accounting for 37.656% and 52.891% of each trajectory class, respectively). These findings provide long-term insights into vegetation resilience in the Al-Ahsa Oasis over 41 years, supporting sustainable urban planning and vegetation and agricultural management. Full article

The identification of areas where pathogenic Rickettsia spp. circulate, using rapid and low-cost serological approaches in sentinel species, may provide essential information for public actions to prevent, diagnose and appropriately treat rickettsiosis. Therefore, in this study we aimed to produce and characterize novel recombinant proteins from Rickettsia rickettsii with potential use in serological detection. The proteins were expressed in Escherichia coli, used in mouse immunization protocols, and also evaluated by indirect IgG ELISA using a cohort of serum samples from wild boars naturally exposed to Rickettsia spp. and from tick-naive farm pigs. The proteins displayed high immunogenicity with the induction of specific murine IgG antibodies, with high avidity after the third dose of immunization. A high IgG seropositivity rate (100%) and antibody avidity (>70%) were observed in wild boar serum samples when evaluated by ELISA. In addition, a significant positive correlation was observed between the swine-specific IgG levels against rPhenAl and rYJBI and the IgG levels against the rOmpA antigen. The novel proteins produced represent promising new immunogenic and antigenic candidates for serological detection of wild animals naturally exposed to Rickettsia spp. Full article

Hybrid lightweight structures increasingly combine cast, wrought, and additively manufactured aluminum alloys, but the mechanical response of their welded joints remains strongly material-dependent. In this study, cast EN AC-42100-T6, wrought EN AW-6082-T6, and laser powder bed fusion (LPBF) AlSi10Mg stress-relieved plates were welded in 4 and 8 mm configurations using cold metal transfer and pulsed multi-control processes over two campaigns. Weld defects, microstructure, hardness profiles, and tensile properties were analyzed using a framework combining a hardness derived local yield-stress descriptor (σ_y,loc), a cumulative hardness deficit (ID_HV), and a porosity increment metric (ΔP). The second campaign eliminated fusion and penetration related defects, but did not mitigate fusion zone porosity in LPBF-related joints, which reached 13.7% in the 8 mm LPBF–Cast joint. Hardness analysis showed the widest hardness-affected region in the wrought alloy, an intermediate response in the cast alloy, and localized alteration in LPBF. Tensile results identified three degradation modes: strength loss associated with heat-affected zone (HAZ) softening in wrought-containing joints, ductility limitation associated with the initial cast condition, and porosity-associated ductility loss in LPBF-related joints. The lower yield strength reduction in LPBF-related joints does not imply improved performance, as fracture remains strongly influenced by fusion zone porosity. The results support material specific mitigation and design strategies for hybrid welded aluminum structures. Full article

Submarine mast covers are critical cantilever appendages subjected to extreme hydrostatic pressure during submerged transit. To ensure structural reliability and control internal defects inherent in heavy-section casting, an integrated design-to-manufacturing framework sequentially linking structural finite element analysis (FEA), fluid volume method (FVM)-based casting simulation, and full-scale experimental sand casting was established. FEA under a 600 m submergence depth (7.0 MPa hydrostatic pressure) identified stress concentrations on the inner surface along the major-axis section. Introducing an optimized fillet radius at a sharp step reduced peak equivalent stress from 216.0 MPa to below 194.0 MPa, securing a safety factor exceeding 2.0 against the yield strength of nickel–aluminum–bronze (390 MPa). MAGMA5 casting simulations verified an unpressurized bottom-gating system (S:R:G = 1.00:2.88:4.80), achieving smooth laminar filling with gate velocities under 1.25 m/s without cold shuts. To mitigate predicted shrinkage porosity, process modifications enlarging riser diameters from Ø30 mm to Ø60 mm and placing chills were implemented in the actual casting trial, while top porosity was removed via machining allowances. Specimens harvested from the full-scale prototype yielded 757.8 MPa UTS, 392.5 MPa yield strength, 17.9% elongation, and 197 HB hardness. Full article

Objective: Current evidence on the association between multiple trace elements and type 2 diabetes mellitus (T2DM) remains limited, particularly regarding combined effects, nonlinear dose–response patterns, and elemental interactions. This study aimed to evaluate the associations between multiple serum trace elements and T2DM using a sequential analytical strategy. Methods: A 1:1 propensity score–matched case–control study based on sex, age, and residence was conducted (637 controls, 637 T2DM cases). Serum concentrations of 18 trace elements were measured using inductively coupled plasma mass spectrometry (ICP-MS). A sequential analytical strategy was applied: LASSO regression for variable selection; logistic regression with single-element (Model 1) and multi-element (Models 2 and 3) approaches for association assessment; weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) for mixture effects; and restricted cubic spline (RCS) for dose–response patterns. Results: Lithium (Li) and tellurium (Te) showed positive associations with T2DM across multiple analytical methods, whereas boron (B), lead (Pb), and vanadium (V) showed inverse associations. WQS identified V and B as the main contributing elements. BKMR did not identify a statistically significant overall association between the mixture and T2DM. Although bivariate interaction plots suggested possible effect modification between V and Al, B, Li, Pb, and Te, formal interaction tests did not reach statistical significance. RCS showed that serum B was significantly associated with T2DM overall and exhibited a significant non-linear dose–response relationship (P-nonlinear = 0.0028). Serum V showed a linear inverse association with T2DM, and serum Li showed a linear positive association. Conclusions: Our findings suggest that Li, Te, B, and V are associated with T2DM, with the most robust evidence for Li, while the evidence for Te was less consistent. In addition, we observed a trend toward a joint association of the trace element mixture, potential effect modification at the point-estimate level between V and Al, B, Li, Pb, and Te, and distinct dose–response patterns for B, Li, and V. These findings highlight the need for further investigation of trace elements in relation to T2DM, with consideration of both individual and combined associations; future validation of these exploratory findings in larger prospective studies and independent populations is warranted. Full article

As a continuation of our previous study on erinacenones A–L (Part 1), thirteen previously undescribed isoindolin-1-ones, erinacenones M–Y (1–13), were isolated from the fermentation broth of Hericium erinaceus. Their structures were elucidated by extensive spectroscopic analyses (1D and 2D NMR, HRESIMS), and the absolute configurations of 1–13 were determined by comparing their specific rotations with those of related phthalimidines (14–23). Compound 11 showed the highest α-glucosidase inhibitory activity among the tested compounds, with 31.5% inhibition at 50 μM. These findings significantly enrich the chemical diversity of isoindolinone metabolites from H. erinaceus and provide a foundation for future structure–activity relationship studies. Full article

This study experimentally investigates the energy, exergy, and economic performance of an enhanced photovoltaic/thermal (PVT) solar collector using micro-finned tubes, twisted-tape inserts, hybrid nanofluid, and nano-enhanced phase-change material (NPCM). Five collector configurations were tested at mass flow rates ranging from 0.008 to 0.042 kg/s. The best-performing configuration combined micro-finned tubes and twisted-tape inserts with SiC-NPCM and a hybrid nanofluid composed of 0.3 vol.% SiC and 0.3 vol.% Al₂O₃ dispersed in water. The experimental uncertainty was reported to be within ±3.5%. The optimized configuration achieved a maximum thermal efficiency of 87.5% and a peak useful thermal output of 189 W at a mass flow rate of 0.033 kg/s, corresponding to a 71.8% improvement compared with the baseline system. Active cooling of the photovoltaic back surface also increased the peak electrical power output to 23.5 W. The maximum overall exergy efficiency reached 12.85%, representing a 117.8% improvement compared with the conventional configuration. Although the micro-finned tubes and NPCM accounted for a substantial share of the initial capital cost, operation at a mass flow rate of 0.024 kg/s provided a favorable compromise between performance and cost, reducing the unit energy cost to USD 0.094/kWh while maintaining thermal-storage stability. The results indicate that the proposed hybrid cooling strategy can improve the thermal and thermodynamic performance of PVT collectors, although further validation under outdoor conditions is recommended. Full article

The greenstone belt of the North China Craton (NCC) records the crustal evolution from the Neoarchean to the post-Archean period, offering critical insights into the ancient tectonic background. This study focuses on the late Paleoproterozoic granitoids in the Daxigou area, located within the greenstone belt of the Qianhuai Block along the northern margin of the NCC. Zircon U–Pb dating indicates that two representative samples (H1 and HZK97-2) were emplaced at 1849 ± 2.1 Ma and 1852 ± 2.0 Ma, respectively (ca. 1.85 Ga). Both samples are characterized by high K₂O (3.99–6.55 wt%) and Na₂O + K₂O contents (4.12–7.92 wt%), high 10,000 × Ga/Al ratios, zircon saturation temperatures (>800 °C), and seagull-type REE patterns, and are identified as A2-type granitic rocks. The Daxigou granitoids show LREE enrichment, negative Eu anomalies (δEu = 0.45–0.63), LILE enrichment, and Nb–Ta–Ti depletion, defining the arc-like trace-element signatures. Integrated with their low Mg# (0.15–0.20), Cr (12–21 ppm), and Ni (0.8–2.5 ppm) contents, negative zircon εHf(t) values (−4.25 to −0.17), Neoarchean Hf model ages (2.5–2.7 Ga), near-chondritic to slightly subchondritic Nb/Ta ratios (15.4–18.3), and high Zr/Hf ratios (41.2–44.1), these features indicate an inheritance from warm subduction-generated Neoarchean TTG protoliths. We propose that the arc-like signatures of the Daxigou granitoids reflect the source inheritance from Neoarchean TTG protoliths. At ca. 1.85 Ga, under an extensional setting, the ancient lower crust (TTG) underwent decompression melting, producing A2-type granitic rocks. They record a transition of the tectonic setting from Neoarchean warm subduction to late Paleoproterozoic post-orogenic extension. Full article

Riparian vegetation in the Araguaia basin remains poorly studied, with few forest inventories addressing its structure and composition. This study sought to integrate attributes of tree communities along the upper, middle, and lower reaches of the basin, evaluating their physiognomic organization and their relationships with edaphic characteristics, aiming to verify the differences between these three regions of the Araguaia River basin. We hypothesize (1) that the structuring and composition of the riparian vegetation community of the different regions of the Araguaia are influenced by different vegetation domains (biomes) and, consequently, the longitudinal gradient of the basin. As a secondary hypothesis (2), we also point out that forest attributes are influenced by edaphic attributes, with the patterns presented by the vegetation being affected by soil characteristics such as fertility and soil physics. We conducted inventories in 27 sites, measuring forest structure, composition, and soil properties. To compare vegetation parameters across locations and with soil characteristics, various analyses were performed, including CCA, PCA, the ANOSIM test, and GLM followed by Tukey’s test. A total of 405 individuals were recorded, belonging to 48 families and 152 species. Fabaceae was the most abundant family, followed by Rubiaceae, Simaroubaceae, and Anacardiaceae. Genera such as Aspidosperma, Andira, and Casearia were particularly diverse. Soil pH and potassium were the main edaphic factors that differentiate vegetation, being evident between gallery forests and cerradão formations. Cerradão areas generally exhibited lower diversity and more acidic soils, while gallery forests showed higher fertility and species richness. Regarding forest composition, the variables that showed significance in the CCA were Ca, Al, and clay. The species were associated with three main edaphic groups. We can highlight species from forest formations associated with soil clay content (Copaifera langsdorffii, Ixora gardneriana, Aspidosperma discolor, Siparuna guianensis, Virola sebifera); a second group consists of riparian forest species associated with aluminum levels (such as Myrsine guianensis, Mabea sp., Alchornea castaneifolia, Vochysia pyramidalis). The third group did not correspond to a specific vegetation formation but comprised species associated with calcium levels, species known not to be associated with water (Matayba guianensis, Handroanthus heptaphyllus, Luehea sp., Anadenanthera colubrina, Piptadenia gonoacantha, Guarea guidonia, Senegalia polyphylla, Curatella americana, Guazuma ulmifolia, Astronium urundeuva, and Rhamnidium elaeocarpum). The ecological heterogeneity of riparian vegetation in the Araguaia basin emphasizes the importance of soil attributes in shaping forest communities, providing baseline information for conservation strategies, reinforcing the need to consider both ecological and edaphic factors in management plans for riparian ecosystems in the Cerrado and Amazon transition zones. Full article