Soil ecosystems represent an important reservoir of microbial diversity with high potential for biotechnological exploitation. Among soil microorganisms, Bacillus species are particularly valued due to their metabolic versatility, stress tolerance, and capacity to produce industrially relevant enzymes and bioactive compounds. This study investigates the impact of controlled soil pretreatments on microbial community dynamics and the subsequent isolation of stress-tolerant Bacillus strains from four climatically distinct regions of Tunisia (Nabeul, Siliana, Medenine, and Tozeur). To selectively enrich spore-forming bacteria, soil samples were subjected to controlled thermal treatments (heat at 40 °C, 60 °C, and 80 °C for 3 h) and calcium carbonate amendments (at concentrations of 5%, 10%, and 15% (w/w)) prior to microbial isolation. Pretreatment of soil samples significantly (p < 0.05) affected microbial counts, revealing differential responses among the studied sites. A total of 40 bacterial isolates were obtained, and 15 representative ones underwent detailed biochemical, physiological, and molecular characterization. 16S rRNA sequencing revealed diverse Bacillus taxa, including B. velezensis, B. subtilis, B. amyloliquefaciens, Cytobacillus horneckiae, together with one unresolved isolate designated Bacillus sp. 107. Physiological profiling revealed that the isolates were mesophilic, moderately halotolerant, and capable of growth under neutral to alkaline conditions. This integrative approach highlights the novelty of combining soil conditioning and microbial isolation strategies. It expands the understanding of soil-derived Bacillus diversity and generates a collection of physiologically robust isolates that may serve as candidates for future functional screening and application-oriented studies.

High-filling epoxy composites possess indispensable and pivotal performance in structural materials and functional devices; However, owing to their intrinsic brittleness and inevitable interface defects, potential stress concentration and structural damage may result in unacceptable losses. Here, a nanopowder-reinforced thixotropic interfacial design strategy was proposed, in which different morphologies of nanosized calcium carbonate were used to reinforce guanidinoacetic acid-modified polyborosiloxane (GPBS), which was then introduced into the organic-inorganic interface of epoxy composites. Owing to the frequency-dependent O→B dynamic bonds and guanidyl-carboxylate structure, the obtained GPBS exhibits an enhanced shear-thickening behavior, with its storage modulus (G') increasing sharply from 34.89 Pa at 0.1 Hz to 69.87 MPa at 100 Hz (an increase of 20,026.51 times). As a result, the corresponding epoxy composites exhibited improved mechanical properties (a 385.6% increase in tensile stress) and impact resistance performance (a force attenuation rate of up to 80%). Meanwhile, SrAl2O4:Eu2+, Dy3+ was incorporated into the composites for stress visualization, and a machine learning-assisted analysis system was developed for signal analysis. This study provides an insight into high-filling functional epoxy composites, holding great application potential in intelligent protection engineering.

Climate, soil factors, and topography play a decisive role in the spatial distribution of species. Predicting the potential distribution of Caragana microphylla Lam. over time is of great significance for maintaining ecological balance, soil and water conservation, and evaluating ecological services in northwestern China. In this study, we used the Global Biodiversity Information Service (GBIF) and SDM Toolbox v2.5 to remove spatial autocorrelation from 103 occurrence records of C. microphylla. We then employed the Maximum Entropy model and ArcGIS software with correlation analysis to select 6 climatic factors, 23 soil factors, and 3 topographic factors for analyzing the potential suitable habitats of C. microphylla, and predicted its distribution changes under three SSP scenarios (2030, 2050, 2070).The results show: (1) Current suitable habitat covers 3.329 million km[2] (34.7% of China), mainly in northern regions; (2) Annual precipitation (bio-12, 350-400 mm), slope (89-90°), Precipitation of Coldest Quarter (bio-19, 0-10 mm), Topsoil Calcium Carbonate (t_CaCO3, 3-5%), and temperature seasonality (bio-4, 1060-1080) were dominant factors (cumulative contribution: 67.6%); (3) Higher CO2 scenarios (SSP37.0) increased suitable areas compared to SSP12.6; (4) Future distribution centers will migrate westward, with maximal displacement (448.51 km) under 2050-SSP24.5. It is recommended that priority be given to the protection of existing populations in Inner Mongolia and Xinjiang. while assisted migration programs could target western expansion zones under high-emission scenarios. In vulnerable areas like the Qinling Mountains, soil amendments should be applied to mitigate waterlogging risks from extreme precipitation events (> 50 mm). Furthermore, a long-term monitoring network should be established across the species' distribution range to dynamically assess population changes of C. microphylla and inform adaptive management strategies.

Carbonate alkalinity is an important environmental stressor in saline-alkali aquaculture. However, its comprehensive effects on the physiological regulation, transcriptional responses, and intestinal microbial homeostasis of Penaeus monodon remain unclear. In this study, shrimp were exposed to high carbonate alkalinity stress for 96 h. Key physiological indicators were evaluated, and gill transcriptome analysis and intestinal 16S rRNA gene sequencing were performed. The results showed that high alkalinity reduced the survival rate of P. monodon, increased hemolymph osmotic pressure and carbonic anhydrase (CA) activity, and simultaneously decreased Na[+]/K[+]-ATPase (NKA) activity and hemolymph ammonia content. Transcriptomic analysis revealed that upregulated genes were mainly enriched in functions related to calcium-ion binding, chitosan degradation, and chitosanase activity and that lysosomal and glycolytic pathways were also activated. In contrast, downregulated genes were associated with chloride ion transport, voltage gated chloride channel activity, and mineral absorption. Intestinal microbial analysis showed that microbial diversity increased significantly and that the relative abundances of short chain fatty acid producing genera, such as Bacteroides and Roseburia, and stress related taxa, such as Selenomonas, increased. In contrast, the relative abundances of opportunistic pathogens, such as Vibrio and Photobacterium, decreased, and the predicted microbial phenotype shifted toward aerobic metabolism. These results indicate that high carbonate alkalinity stress may affect shrimp survival by disrupting gill ion homeostasis, inducing chitin turnover and cuticle remodeling responses, and altering the intestinal microbial community. Collectively, these findings provide a mechanistic basis for determining shrimp tolerance thresholds in saline alkali aquaculture and for developing breeding strategies.

Portable near-infrared (NIR) spectroscopy represents a rapid, non-destructive, and cost-effective alternative to conventional laboratory methods for soil analysis. This study integrates portable NIR spectroscopy with spectral pre-processing, wavelength selection, and machine learning (ML) techniques to estimate ten soil properties: bulk density, calcium carbonate, clay, extractable potassium, organic carbon, sand, silt, total carbon, total nitrogen, and soil pH. Two methodological approaches were assessed. The first approach involved pre-processing raw spectra followed by Principal Component Analysis (PCA). The second approach utilized Extra Trees Regressor (ETR)-based wavelength selection to identify the 150 most informative wavelengths. The ETR-selected wavelengths substantially improved five-fold cross-validation performance for calcium carbonate (R[2] = 0.949 ± 0.015), organic carbon (R[2] = 0.924 ± 0.015), total carbon (R[2] = 0.919 ± 0.026), total nitrogen (R[2] = 0.893 ± 0.015), and soil pH (R[2] = 0.884 ± 0.005). Statistical analyses demonstrated that the acquired spectra were consistent and the proposed framework delivered robust and reliable predictive performance across the five-fold cross-validation experiments.

Drug-resistant infections caused by intracellular methicillin-resistant Staphylococcus aureus (MRSA) remain difficult to treat because conventional antibiotics exhibit limited accumulation and retention within infected macrophages. Here, we developed a macrophage-targeted, pH-responsive calcium carbonate nanoplatform (CaVPM) for intracellular delivery of vancomycin (Van). Porous CaCO3 nanoparticles were used as the drug-loading core, polydopamine (PDA) provided a protective and functional shell, and a mannose-containing NBD ligand enabled macrophage targeting through mannose receptor recognition. The resulting CaVPM nanoparticles had a hydrodynamic diameter of approximately 255 nm and a Van drug-loading content of 5.1 ± 0.9% (w/w). CaVPM exhibited limited Van leakage under physiological conditions but accelerated drug release under acidic conditions. Mannose receptor-mediated uptake significantly enhanced intracellular delivery of CaVPM in RAW264.7 macrophages. Consistent with the enhanced cellular uptake, CaVPM increased intracellular Van accumulation from 28.52 ± 0.63 μg/mg protein for free Van to 57.58 ± 9.69 μg/mg and markedly reduced intracellular MRSA burden in vitro. In an MRSA peritonitis mouse model, intravenously administered CaVPM showed superior activity against intracellular bacteria compared with free Van. These findings demonstrate that mannose-directed cellular uptake combined with acid-responsive Van release can improve antibiotic delivery to intracellular MRSA reservoirs and provide a potential nanotherapeutic strategy for persistent intracellular infections.

Eggshell quality is a key economic trait in commercial layer production, which profoundly affects economic profits, flock elimination rate, and feeding management. Frequent occurrence of cracked, thin-shelled eggs has long plagued intensive laying hen farming. This study aimed to dissect the molecular mechanisms and regulatory networks underlying staged eggshell mineralization across the pre-mineralization, initial mineralization, and rapid mineralization phases in laying hens, and explore their links to eggshell quality and shell defect in production. By integrating RNA-sequencing, temporal expression profiling and WGCNA, we screened core functional genes and signaling pathways in uterus that governing the variation of eggshell thickness. In pre-mineralization stage, high expression of Ovalbumin (OVAL) may inhibit premature calcium carbonate crystallization and avoid abnormal shell development. During rapid mineralization, genes encoding eggshell matrix proteins, ATPase, TRP (transient receptor potential), SLC (Solute carrier) and collagen family members coordinately maintained uterine cellular calcium homeostasis, sustained calcium supply for eggshell deposition, and ultimately determined eggshell thickness and strength. Meanwhile, calcium concentration in uterine fluid increased gradually along with mineralization and remained stable throughout rapid mineralization phase, providing a steady calcium supply basis for preventing eggshell defects in commercial laying hen production. Findings of this study provided targets and theoretical support for the breeding of laying hen breeds, the regulation of nutritional management, and the optimization of farming environment management.

Diabetic wounds are characterized by excessive oxidative stress, persistent inflammation, and impaired tissue regeneration, which collectively hinder normal wound healing. Here, we developed a near-infrared (NIR)-responsive sodium alginate hydrogel incorporating nano‑iron sulfide (nFeS) through mild gelation mediated by calcium carbonate and glucono-δ-lactone. The resulting SA-nFeS hydrogel exhibited a porous structure, favorable rheological properties, hydrogen peroxide-responsive degradation, radical-scavenging activity, and good cytocompatibility. NIR irradiation accelerated the release of Fe from the hydrogel, increasing the cumulative release from approximately 35.5% to 75.4% over 48 h. In cells exposed to oxidative stress, the NIR-treated SA-nFeS hydrogel markedly reduced intracellular reactive oxygen species and promoted Nrf2 nuclear translocation, accompanied by decreased Keap1 expression and increased expression of the downstream antioxidant proteins HO-1, SOD1, SOD2, and GPX4. Furthermore, the hydrogel suppressed pro-inflammatory macrophage markers and cytokines while increasing the expression of CD206, Arg-1, and IL-10, indicating a shift toward a pro-healing macrophage phenotype. In a streptozotocin-induced diabetic full-thickness wound model, SA-nFeS combined with NIR irradiation achieved approximately 93% wound-area reduction by Day 14 and promoted re-epithelialization, granulation tissue formation, and collagen deposition. No obvious histopathological abnormalities were observed in the major organs. Collectively, these findings demonstrate that the NIR-responsive SA-nFeS hydrogel promotes diabetic wound repair by activating endogenous antioxidant defense and modulating the inflammatory microenvironment, providing a promising therapeutic platform for chronic wound management.

Interactions between carbonates and silicates play a central role in many industrial and planetary processes. Although current knowledge is largely limited to silicate-carbonate exchange mechanisms, high-pressure compounds incorporating both carbonate and silicate units have long been anticipated. Here we report the synthesis of the high-pressure silicate-diorthocarbonate CaSiC2O7 at 122(2) GPa and 2800(200) K. CaSiC2O7 is based on the framework of vertex-sharing SiO6 octahedra and CO4 tetrahedra. Ab initio calculations are consistent with the experimental results and indicate dynamical and mechanical stability of this phase over a wide pressure range. These findings reveal an additional pathway for carbonate-silicate interaction in carbonate-rich deep-mantle environments. CaSiC2O7 has a density lower than that of major mantle minerals and exhibits comparatively low acoustic velocities, suggesting that silicate-carbonates may contribute to seismic anomalies near the core-mantle boundary.

Pearl powder, nacre, and nacre-derived water-soluble matrix (WSM) are natural mineral-organic materials with growing relevance for bone-regenerative research. Their biological activity appears to depend not only on calcium carbonate content but also on soluble matrix components that can influence osteoblast behavior, mineral deposition, and cellular stress responses. This narrative review compares pearl-specific osteogenic studies in cell, scaffold, and defect-repair models with selected comparator nanoparticle studies used to frame unresolved safety questions. The pearl-specific literature generally supports osteogenic activity, particularly in preosteoblast or osteoblast-lineage models and WSM-containing materials, but the evidence remains heterogeneous because species source, extraction method, particle size, release behavior, dose, and endpoint selection differ across studies. Evidence linking nano-pearl powder to autophagy-associated osteogenic differentiation is promising, especially in MC3T3-E1 models, but the existing pearl-specific literature provides limited direct evidence for high-dose toxicity, impaired autophagic flux, immunogenicity, heavy-metal-related risk, degradation-matched repair, or chronic biosafety. Future work should integrate material characterization, dose-response testing, oxidative and mitochondrial readouts, autophagic flux analysis, and osteogenic endpoints into a single experimental design. Such studies will be needed to define whether WSM-based or nano-pearl formulations can provide a reproducible and safe osteogenic window for bone-regenerative biomaterial development.

Microbially Induced Calcium Carbonate Precipitation (MICP) is an environmentally friendly biotechnology used to consolidate materials and soils at room temperature. While the bacterial enzymatic reaction underlying MICP and its application at large scale have been extensively researched, less is known about the colloidal interactions and potential aggregation of the calcium carbonate particles precipitated through this process. In this work, we study the composition, structure, and dynamics of the colloidal aggregates formed in mineralizing MICP solutions. To enable real-time visualization and full control over the mineralization process, the bacteria-driven assembly of colloidal particles is investigated inside microfluidic droplets. Brightfield microscopy, confocal scanning laser microscopy, and Raman spectroscopy revealed that bacterial cells and calcium carbonate particles co-assemble into open, fractal networks during the biomineralization process. Such findings indicate that a simple colloidal aggregation process governs the assembly of microbially precipitated particles in complex MICP media.

Karst lakes are dynamic aquatic systems where carbonate weathering, biological production, and mineral precipitation jointly regulate carbon cycling, nutrient retention, and contaminant fate. However, field evidence linking the biological carbon pump (BCP) to phosphorus (P) removal and heavy metals (HMs) immobilization in natural karst lakes remains limited. This study investigated Tianchi Lake (TCH) in Southwest China using high-frequency hydro-chemical monitoring, seasonal sampling, sediment P fractionation, HMs analysis, and SEM-EDS characterization. Results showed pronounced seasonal covariation among NEP and hydrochemical variables commonly associated with BCP-related processes. During summer, positive NEP coincided with higher pH, dissolved oxygen (DO), and calcite saturation and with lower Ca[2+], HCO3[-], pCO2, and water-column total phosphorus (TP). These coordinated seasonal patterns were consistent with enhanced net autotrophic metabolism and photosynthetic DIC uptake. The cumulative NEP over the approximately one-year monitoring period was 9.15 g C m[-2], indicating net autotrophy at the ecosystem-metabolism level. Daily mean NEP was positive only in summer, when the cumulative NEP reached 53.86 g C m[-2]. Sedimentary P was also highest in summer, with total P reaching 330.98 mg kg[-1]. The BCP-related P fractions HCl-P, BD-P, and NaOH-SRP reached 32.64, 85.51, and 116.39 mg kg[-1], respectively, and together accounted for an average of 65.19% of sedimentary P. HMs (Cr, Zn, Pb, Fe, Mn) showed coupled water-sediment redistribution, with lower dissolved concentrations but stronger sediment enrichment in spring and summer respectively. Total sedimentary metals peaked at 188.99 mg kg[-1] in summer. During the monitoring period, the coordinated seasonal patterns of NEP, carbonate-system variables, sedimentary P fractions, and metal distributions were consistent with a conceptual mechanism in which carbonate precipitation and Fe-oxide formation under periods of stronger net autotrophic metabolism may contribute to coupled carbon sequestration, P retention, and partial HMs immobilization.

Indocyanine green (ICG) holds promise for near-infrared-II (NIR-II) fluorescence imaging but is hindered by poor photostability, rapid clearance, and lack of targeting specificity. To address these challenges, we engineered a tumor-targeted nanoprobe (cRGD@ICN) by encapsulating ICG within a calcium carbonate (CaCO3) core, followed by surface functionalization with phospholipids and cyclic RGD (cRGD) peptides. The CaCO3 encapsulation enhanced ICG photostability and amplified NIR-II emission by 9.21-fold relative to free ICG. Meanwhile, cRGD conjugation enabled active targeting of integrin αvβ3, a receptor overexpressed on diverse tumor types. cRGD@ICN showed receptor-mediated endocytosis with specific uptake in HCT116, 4T1, and U87 cells in vitro, along with selective accumulation in human ex vivo colorectal cancer tissues. In vivo NIR-II fluorescence imaging revealed that cRGD@ICN achieved high-contrast tumor monitoring with a signal-to-background ratio (SBR) of 6.54 at 16 h postinjection in HCT116 tumor-bearing mice─markedly outperforming the nontargeted control. More importantly, it also exhibited remarkable tumor-targeting ability across other tumor models (U87, 4T1). With precise tumor imaging, we performed real-time NIR-II fluorescence-guided resection of colorectal tumors, confirmed by the absence of residual tumor in the surgical cavity by H&E analysis. Moreover, primary biosafety assessments confirmed favorable biocompatibility. This work provides a promising strategy to transform ICG into a high-performance NIR-II fluorescent nanoprobe and offers a potential approach for precision image-guided oncologic surgery.

Background: Patients with chronic kidney disease (CKD) undergoing hemodialysis commonly present multiple comorbidities and require complex medication regimens. Polypharmacy increases the risk of clinically relevant drug interactions that may compromise treatment safety and effectiveness. Objective: To estimate the prevalence of potential drug interactions among patients with CKD undergoing hemodialysis and classify these interactions according to clinical risk and mechanism of action. Methods: A cross-sectional study was conducted with patients undergoing hemodialysis at a dialysis clinic in Southern Santa Catarina, Brazil. Potential drug interactions were identified using the Medscape and Drugs.com databases and classified according to severity (major, moderate, or minor) and mechanism of action. Results: A total of 151 patients were included. Potential drug interactions were identified in all participants (973 interactions; mean 6.4 per patient). Of these, 234 (24.0%) were classified as major, 545 (56.0%) as moderate, and 194 (19.9%) as minor. The most frequent major interactions involved furosemide + losartan (n = 8) and acetylsalicylic acid + clopidogrel (n = 6). Among moderate interactions, the most common were sevelamer + calcium carbonate (n = 14) and losartan + amlodipine (n = 12). The most frequent minor interactions involved epoetin alfa + acetylsalicylic acid (n = 14) and epoetin alfa + calcium carbonate (n = 10). Pharmacodynamic interactions predominated, mainly involving additive effects of cardiovascular medications. Conclusions: Potential drug interactions were highly prevalent among patients undergoing hemodialysis, with moderate-severity interactions predominating. Routine screening for potential drug interactions may support safer prescribing, optimize pharmacotherapy, and strengthen multidisciplinary medication management in this high-risk population.