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This study aims to develop multi-functional bio-safe dental resin composites with capabilities for mineralization, high in vitro biocompatibility, and anti-biofilm properties. To address this issue, experimental resin composites consisting of UDMA/TEGDMA-based dental resins and low quantities (1.9, 3.8, and 7.7 vol%) of 45S5 bioactive glass (BAG) particles were developed. To evaluate cellular responses of resin composites, MC3T3-E1 cells were (1) exposed to the original composites extracts, (2) cultured directly on the freshly cured resin composites, or (3) cultured on preconditioned composites that have been soaked in deionized water (DI water), a cell culture medium (MEM), or a simple HEPES-containing artificial remineralization promotion (SHARP) solution for 14 days. Cell adhesion, cell viability, and cell differentiation were, respectively, assessed. In addition, the anti-biofilm properties of BAG-loaded resin composites regarding bacterial viability, biofilm thickness, and biofilm morphology, were assessed for the first time. In vitro biological results demonstrated that cell metabolic activity and ALP expression were significantly diminished when subjected to composite extracts or direct contact with the resin composites containing BAG fillers. However, after the preconditioning treatments in MEM and SHARP solutions, the biomimetic calcium phosphate minerals on 7.7 vol% BAG-loaded composites revealed unimpaired or even better cellular processes, including cell adhesion, cell proliferation, and early cell differentiation. Furthermore, resin composites with 1.9, 3.8, and 7.7 vol% BAG could not only reduce cell viability in S. mutans biofilm on the composite surface but also reduce the biofilm thickness and bacterial aggregations. This phenomenon was more evident in BAG7.7 due to the high ionic osmotic pressure and alkaline microenvironment caused by BAG dissolution. This study concludes that multi-functional bio-safe resin composites with mineralization and anti-biofilm properties can be achieved by adding low quantities of BAG into the resin system, which offers promising abilities to mineralize as well as prevent caries without sacrificing biological activity. [ABSTRACT FROM AUTHOR]

The mineralization of octacalcium phosphate (OCP) crystals in gel media was studied in the presence of a magnetic field. OCP crystal growth was found to be dependent on mineralization temperature, mineralization time, and the magnetic field. Higher temperatures significantly reduced the mineralization time, which is crucial for directional growth of OCP crystals. The growth of OCP crystals was accelerated by the applied magnetic field, while OCP crystals generated in the presence of a magnetic field exhibited increased length and width of oriented growth. This study provides valuable insights into the influence of mineralization factors in bioprocessing-inspired manufacturing processes. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to evaluate the immunohistochemical effect of hyaluronic acid (HA) on the mineralization rate of the reparative dentin when it is used as a mixing medium with mineral trioxide aggregate (MTA). Materials and Methods: Direct pulp capping (DPC) was performed on 90 teeth from 10 dogs that had been experimentally exposed. The exposed pulps were divided into three groups according to the mixing medium with MTA: Group I: MTA + distilled water (control group), Group II: MTA + hybrid cooperative complex HA (HCC-HA), Group III: MTA + high molecular weight HA (HMW-HA). After pulp capping, all cavities were restored with final restoration. The dogs were divided randomly into five groups (two dogs each) according to the evaluation periods (7, 14, 21, 30, and 60) days. At the end of the study, the dogs were euthanized, and the sampled teeth were processed for immunohistochemical investigation. Results: Both types of HA (HCC-HA, HMW-HA) showed an increase in the expression of alkaline phosphatase (ALP) at a higher rate than using distilled water with MTA. Conclusions: Within the limitations of this study, HA proved to be an effective additive to MTA for DPC. [ABSTRACT FROM AUTHOR]

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Agricultural practices such as fertilization considerably influence soil carbon dioxide (CO2) fluxes that cause climate changes. The study aims to test the influence of various organic (vermicompost, VC, and rabbit manure, RM) and bio (Azotobacter and Azospirillum) fertilizers in addition to incubation times on CO2flux, carbon (C) mineralization kinetic, and some soil chemical properties. The dual exponential equation was the best one to describe carbon mineralization kinetics compared to the 1st and 2nd order equations. Carbon half-lives were resided by 18.98, 1.97, 2.00, 1.89, and 2.53 years for control, VC without and with bio, RM without and with bio treatments, respectively. The results exposed that applying VC and RM without or with bio-fertilizer reduced soil reaction (pH) that differ than control treatment after 2 months incubation. Applying VC and RM caused a significant increase in soil salinity (EC) compared to the control. Available nitrogen (N), phosphorus (P) and potassium (K) were significantly enhanced with adding different fertilizers compared to pre-treated soil. It is found that adding organic and bio-fertilizers improved fertility and soil quality. [ABSTRACT FROM AUTHOR]

The widespread Cenozoic Himalayan leucogranites (HLs) are representative rocks evolving from relatively pure crust-derived melts with few mantle material inputs and are believed to be highly fractionated and rare-metal mineralization developed. Over the past several decades, high-quality geochronological and geochemical analyses for the HLs have facilitated exploring the metamorphism, deformation, anatexis, and tectonic settings, enabling us to decipher the evolution process of the Himalayan orogen. In this study, we collected a large amount of geochronological, geochemical, and thermodynamic data from previous studies. Generally, the HLs exhibit (strongly) peraluminous (1.06–1.22) features and are characterized by high SiO2 (70.95–75.08 wt. %) and Al2O3 (14.18–15.85 wt. %) and low TiO2 (0.02–0.26 wt. %), MgO (0.07–0.73 wt. %), MnO (0.01–0.07 wt. %), and total iron (FeOT = 0.44–1.71 wt. %) contents, and are enriched in large ion lithophile elements (e.g. K, Rb, Pb, U). Moreover, rare-metal elements (Li, Be, Ta, W, Sn) also show their enrichments in the HLs; and the deviations of K/Rb (72.16–190.45), Zr/Hf (15.00–35.19), Nb/Ta (2.65–12.75), and Y/Ho (26.07–36.75) ratios from the chondritic values are also notable. All these geochemical structures above suggest that the HLs are (highly) fractionated. Considering the diverging whole-rock isotopic Sr and Nd compositions of the HLs, with the (87Sr/86Sr)t ratios and εNd(t) values mostly ranging from 0.7159 to 0.8052 and −16.78 to −10.43, respectively, the source rocks of the HLs should be multiplex. Additionally, different melting mechanisms (including fluid-absent/present partial melting of muscovite, biotite, and hornblende) can be identified in the HL productions. The occurrences of beryl (Be), columbite (Nb and Ta), spodumene (Li), and many other rare-metal minerals have been frequently reported recently, suggesting the enrichment of rare-metal elements associated with the HLs. To provide a comprehensive and meticulous summary of these HLs (1593 leucogranite samples), we divide them into five stages based on different tectonic backgrounds. After comparing them, we propose that: (1) from Stage I to V, the HL emplacements were strongly related to the tectonic backgrounds: thickened crust from ca. 49 to 40 Ma (I), transition from compression to N-S extension (onset of the South Tibetan Detachment System (STDS)) from ca. 39 to 30 Ma (II), large-scale N-S extension (active movement of the STDS) from ca. 29 to 15 Ma (III), N-S extension to E-W extension tectonic transition (construction of N-S trending rifts (NSTRs)) from ca. 14 to 7 Ma (IV) and rapid uplift of two Himalayan syntaxes from ca. 6 to 2 Ma (V), respectively; (2) the coeval leucogranites emplaced in the Tethyan Himalayas (THLs) and Greater Himalayas (GHLs) had many similarities (particularly in Stages III and IV) in: geochemical compositions, peak emplacement ages, tectonic backgrounds, melting mechanisms, source domains, and fractional crystallization degrees; (3) materials from the Lesser Himalayan Sequence were increasingly significant in producing the HLs from the Eocene to the Pleistocene temporally, and from the Tethyan Himalayan Sequence to the Greater Himalayan Crystalline Complex spatially; (4) owing to the depleted abundances of rare-metal elements in mafic source rocks (e.g. amphibolites) and relatively lower fractional crystallization degrees of the Eocene leucogranites, rare-metal mineralization was rarely reported; (5) excessive fractional crystallization may be the dominant driving force for enriching rare-metal elements (Li-Be-Nb-Ta-W-Sn) of the HLs, making the Himalayas a new potential global orogen scale of polymetallic ore belt. [ABSTRACT FROM AUTHOR]

Native and biomimetic DNA structures have been demonstrated to impact materials synthesis under a variety of conditions but have only just begun to be explored in this role compared to other biopolymers such as peptides, proteins, polysaccharides, and glycopolymers. One selected DNA aptamer has been explored in calcium phosphate and calcium carbonate mineralization, demonstrating sequence-dependent control of kinetics, morphology, and crystallinity. This aptamer is here applied to a biologically-relevant bone model system that uses collagen hydrogels. In the presence of the aptamer, intrafibrillar collagen mineralization is observed compared to negative controls and a positive control using well-studied poly-aspartic acid. The mechanism of interaction is explored through affinity measurements, kinetics of calcium uptake, and kinetics of aptamer uptake into the forming mineral. There is a marked difference observed between the selected aptamer containing a G-quadruplex secondary structure compared to a control sequence with no G-quadruplex. It is hypothesized that the equilibrium interaction of the aptamer with calcium-phosphate precursors and with the collagen itself leads to slow kinetic mineral formation and a morphology appropriate to bone. This points to new uses for DNA aptamers in biologically-relevant mineralization systems and the possibility of future biomedical applications. Collagen is the protein structural component that mineralizes with calcium phosphate to form durable bone. Crystalline calcium phosphate must be infused throughout the collagen fiber structure to produce a strong material. This process is assisted by soluble proteins that interact with both calcium phosphate precursors and the collagen protein and has been proposed to follow a polymer-induce liquid precursor (PILP) model. Further understanding of this model and control of the process through synthetic, biomimetic molecules could have significant advantages in biomedical, restorative procedures. For the first time, synthetic DNA aptamers with specific secondary structures are here shown to influence and direct collagen mineralization. The mechanism of this process has been studied to demonstrate an important equilibrium between the DNA aptamer, calcium phosphate precursors, and collagen. [Display omitted] [ABSTRACT FROM AUTHOR]

Harnessing solar energy using semiconductor-based materials to generate charge pairs to effectively drive photo-redox reactions has been envisioned as a promising approach toward a sustainable future. In this arena, the metal sulfide nanoparticles have demonstrated excellent performance in photomineralizing colored matter. However, their small surface area and relatively slow charge transfer has limited their practical applications. Therefore, for the effective mineralization of colored matter, we devise and construct the Sn2S3–In2S3 S-scheme in collaboration with 2D graphene oxide nanosheets. The material offers a well-defined nanosheet and nanoflake morphology for the effective contact with and catalysis of crystal violet (CV) dye as a model contaminant. Compared to Sn2S3–In2S3/GO, the pristine Sn2S3 and Sn2S3–In2S3 cause negligible degradation of CV using a visible-light source. This enhanced photocatalysis is supported by the peculiar properties of GO, such as its high surface area, electron-shuttling performance, and ability to prevent charge back-recombination. Under simulated conditions, more than 99% of CV was mineralized within 60 min of contact time. The photodegradation follows pseudo-first-order kinetics with a rate constant (Kt) = 0.02317 min−1. Furthermore, the photo mineralization of CV dye was thoroughly investigated using the GC-MS technique. More importantly, Sn2S3–In2S3/GO exhibits promising recyclability over multiple degradation cycles. [ABSTRACT FROM AUTHOR]

CO2 capture and storage in geological reservoirs have the potential to significantly mitigate the effects of anthropogenic gas emissions on global climate. Here, we report the results of the first laboratory experiments of CO2 injection in continental flood basalts of South America. The results show that the analyzed basalts have a mineral assemblage, texture and composition that efficiently allows a fast carbonate precipitation that starts 72 h after injection. Based on the availability of calcium, chemical monitoring indicates an estimated CO2 storage of ~ 75%. The carbonate precipitation led to the precipitation of aragonite (75.9%), dolomite (19.6%), and calcite (4.6%). [ABSTRACT FROM AUTHOR]

Problems of salt-affected soils can be alleviated by organic amendments, but their nitrogen (N) mineralization pattern, crucial to providing proper N synchronization with crop demand, can differently be influenced by salinity and sodicity. An incubation study was carried out objectively to investigate the mineralization and kinetic release of N in three organic wastes (OWs) – rice husk (RH), rice straw (RS), burnt rice husk (BRH) in saline-sodic (SS) and sodic (Sod) soils. The OWs were mixed into the soils and inorganic N was measured under aerobic condition (field capacity) for 28 days followed by waterlogged condition until day-112. The mineral N mineralized from all OWs was, on average, <20% of N input released into the mineral N pool with RS mineralized the highest. Mineralization occurred less in SS than in Sod soil. Nitrogen mineralization peaked at 28 days with net immobilization observed after 21-day of waterlogged condition. The mineralization rate and mineralizable N pool of these OWs had a better fit to two-pool than first-order model, showing the highest quantities in respective RS, RH and BRH and fast N pools constant rate greater in SS than in Sod soils. Net N mineralization differed among OWs, soils and incubation times. The N mineralization pattern of OWs was a function of both N sources and soil salinity. The pool and rate of mineralizable N were predicted from the initial material's total N. The findings can lead to proper N management for jasmine rice in salt-affected soils using inorganic wastes to partially supply N. [ABSTRACT FROM AUTHOR]

Bostonite rocks are widely spread in the Central Eastern Desert (CED) of Egypt, they are found in the form of sills or dykes injected in the Precambrian rocks. Postgeosynclinal (Hammamat) sediments were intruded by Postorogenic bostonites. The study of this area, using ground geophysical methods, aimed at tracking the radioactive mineralization under the surface, based on the possible association of this radioactive mineralization with some other mineralizations such as sulphides. The application of the self-potential survey shows that the highest negative anomalies are associated with the South El-Atshan bostonite sill and its contact zones. The depths to the centres of some selected anomalies range from 5.7 m to 24 m, half-widths oscillate from 6 to 32 m, with shallow dips towards the west and east directions. The horizontal-loop electromagnetic (HLEM) survey, which was conducted using four frequencies, revealed the presence of two conductive bodies. These conductive bodies possess narrow widths and depths, ranging from 25 m to 27 m, dipping towards the west direction with shallow angles of 25◦ and 40◦, respectively. In addition, the induced polarization (IP) profile shows high chargeability values reaching more than 7.9 mV/V at depths starting from about 10 m to about 35 m. This zone corresponds to a high-resistance zone that may reflect a subsurface disseminated mineralization. The integration of the results obtained using the three techniques makes it possible to determine the most appropriate zones for the development of exploration in the area of investigation. [ABSTRACT FROM AUTHOR]

Micro- plastics (MPs) pose significant global threats, requiring an environment-friendly mode of decomposition. Microbial-mediated biodegradation and biodeterioration of micro-plastics (MPs) have been widely known for their cost-effectiveness, and environment-friendly techniques for removing MPs. MPs resistance to various biocidal microbes has also been reported by various studies. The biocidal resistance degree of biodegradability and/or microbiological susceptibility of MPs can be determined by defacement, structural deformation, erosion, degree of plasticizer degradation, metabolization, and/or solubilization of MPs. The degradation of microplastics involves microbial organisms like bacteria, mold, yeast, algae, and associated enzymes. Analytical and microbiological techniques monitor microplastic biodegradation, but no microbial organism can eliminate microplastics. MPs can pose environmental risks to aquatic and human life. Micro-plastic biodegradation involves fragmentation, assimilation, and mineralization, influenced by abiotic and biotic factors. Environmental factors and pre-treatment agents can naturally degrade large polymers or induce bio-fragmentation, which may impact their efficiency. A clear understanding of MPs pollution and the microbial degradation process is crucial for mitigating its effects. The study aimed to identify deteriogenic microorganism species that contribute to the biodegradation of micro-plastics (MPs). This knowledge is crucial for designing novel biodeterioration and biodegradation formulations, both lab-scale and industrial, that exhibit MPs-cidal actions, potentially predicting MPs-free aquatic and atmospheric environments. The study emphasizes the urgent need for global cooperation, research advancements, and public involvement to reduce micro-plastic contamination through policy proposals and improved waste management practices. [ABSTRACT FROM AUTHOR]

The Chinese Bayan Obo deposit is a world-class rare earth element (REE) deposit with considerable niobium (Nb) and iron (Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead (U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma (n  = 99), 438 ± 7 Ma (n  = 93), and 268 ± 5 Ma (n  = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general. [ABSTRACT FROM AUTHOR]

Crushing waste concrete and using it directly as RAs has the disadvantages of high porosity and high water absorption. To achieve the reuse of resources, the researchers use microbial mineralization methods to further reinforce RAs. In this paper, the effect of the microbial carbonic anhydrase mineralization method on the water absorption of RAs was investigated, and the macroscopic analysis was performed by determining the indexes of water absorption and apparent density of RAs before and after the modification, and the microscopic analysis of RAs by using the methods of SEM, XRD, DSC, and EDS as well. According to the microscopic analysis, the mineralization products of microorganisms are calcium carbonate crystals, and with the increase in microbial liquid concentration, the water absorption rate of RAs shows a trend of decreasing and then increasing, and it can be found through the microscopic morphology that abundant mineralization products attached to the surface of the aggregate lead to the surface of the aggregate becoming rougher and more porous. The method of soaking the RAs in 3% bacterial solution and 0.1 mol/L calcium acetate solution followed by carbonation with 20% CO2 resulted in a 4.85% reduction in water absorption. [ABSTRACT FROM AUTHOR]

Ankylosing spondylitis (AS) is a chronic inflammatory disease, characterized by excessive new bone formation. We previously reported that the complement factor H-related protein-5 (CFHR5), a member of the human factor H protein family, is significantly elevated in patients with AS compared to other rheumatic diseases. However, the pathophysiological mechanism underlying new bone formation by CFHR5 is not fully understood. In this study, we revealed that CFHR5 and proinflammatory cytokines (TNF, IL-6, IL-17A, and IL-23) were elevated in the AS group compared to the HC group. Correlation analysis revealed that CFHR5 levels were not significantly associated with proinflammatory cytokines, while CFHR5 levels in AS were only positively correlated with the high CRP group. Notably, treatment with soluble CFHR5 has no effect on clinical arthritis scores and thickness at hind paw in curdlan-injected SKG, but significantly increased the ectopic bone formation at the calcaneus and tibia bones of the ankle as revealed by micro-CT image and quantification. Basal CFHR5 expression was upregulated in AS-osteoprogenitors compared to control cells. Also, treatment with CFHR5 remarkedly induced bone mineralization status of AS-osteoprogenitors during osteogenic differentiation accompanied by MMP13 expression. We provide the first evidence demonstrating that CFHR5 can exacerbate the pathological bone formation of AS. Therapeutic modulation of CFHR5 could be promising for future treatment of AS. Key messages: Serum level of CFHR5 is elevated and positively correlated with high CRP group of AS patients. Recombinant CFHR5 protein contributes to pathological bone formation in in vivo model of AS. CFHR5 is highly expressed in AS-osteoprogenitors compared to disease control. Recombinant CFHR5 protein increased bone mineralization accompanied by MMP13 in vitro model of AS. [ABSTRACT FROM AUTHOR]

Antioxidant vanillin (4-hydroxy-3-methoxybenzaldehyde) is used as a flavoring in foods, beverages, and pharmaceuticals. Vanillin possesses various biological effects, such as antioxidant, anti-inflammatory, antibacterial, and anticancer properties. This study aimed to investigate the biological activities of vanillin purified from Adenophora triphylla var. japonica Hara on bone-forming processes. Vanillin treatment induced mineralization as a marker for mature osteoblasts, after stimulating alkaline phosphatase (ALP) staining and activity. The bone-forming processes of vanillin are mainly mediated by the upregulation of the bone morphogenetic protein 2 (BMP2), phospho-Smad1/5/8, and runt-related transcription factor 2 (RUNX2) pathway during the differentiation of osteogenic cells. Moreover, vanillin promoted osteoblast-mediated bone-forming phenotypes by inducing migration and F-actin polymerization. Furthermore, we validated that vanillin-mediated bone-forming processes were attenuated by noggin and DKK1. Finally, we demonstrated that vanillin-mediated antioxidant effects prevent the death of osteoblasts during bone-forming processes. Overall, vanillin has bone-forming properties through the BMP2-mediated biological mechanism, indicating it as a bone-protective compound for bone health and bone diseases such as periodontitis and osteoporosis. [ABSTRACT FROM AUTHOR]

Mineralogical and U–Pb (ID-TIMS) geochronological studies of garnets from three types of scarn associations of the Khovu-Aksy Ag–Bi–Cu–Ni–Co deposit (Republic of Tuva) are carried out. The U–Pb garnet age estimate (404 ± 2 Ma) is close to the Early Devonian stage of basite and alkaline-basite magmatism identified within the Tuva trough of the Altai-Sayan folded area. The age of the scarn formation and the associated early stage of mineralization of the Khovu-Aksy Ag–Bi–Cu–Ni–Co deposit has been established for the first time. [ABSTRACT FROM AUTHOR]

The first case of hydrothermal brecciated crusts composed of goethite with quartz veinlets is described for the Sea of Japan. [ABSTRACT FROM AUTHOR]

The Sunnhordland area in SW Norway hosts more than 100 known mineral occurrences, mostly of volcanogenic massive sulfide (VMS) and orogeny Au types. The VMS mineralization is hosted by plutonic, volcanic and sedimentary lithologies of the Lower Ordovician ophiolitic complexes. This study presents new trace element and δ34S data from VMS deposits hosted by gabbro and basalt of the Lykling Ophiolite Complex and organic-rich sediments of the Langevåg Group. The Alsvågen gabbro-hosted VMS mineralization exhibits a significant Cu content (1.2 to >10 wt.%), with chalcopyrite and cubanite being the main Cu-bearing minerals. The enrichment of pyrite in Co, Se, and Te and the high Se/As and Se/Tl ratios indicate elevated formation temperatures, while the high Se/S ratio indicates a contribution of magmatic volatiles. The δ34S values of the sulfide phases also support a substantial influx of magmatic sulfur. Chalcopyrite from the Alsvågen VMS mineralization shows significant enrichment in Se, Ag, Zn, Cd and In, while pyrrhotite concentrates Ni and Co. The Lindøya basalt-hosted VMS mineralization consists mainly of pyrite and pyrrhotite. Pyrite is enriched in As, Mn, Pb, Sb, V, and Tl. The δ34S values of sulfides and the Se/S ratio in pyrite suggest that sulfur was predominantly sourced from the host basalt. The Litlabø sediment-hosted VMS mineralization is also dominated by pyrite and pyrrhotite. Pyrite is enriched in As, Mn, Pb, Sb, V and Tl. The δ34S values, which range from −19.7 to −15.7 ‰ VCDT, point to the bacterial reduction of marine sulfate as the main source of sulfur. Trace element characteristics of pyrite, especially the Tl, Sb, Se, As, Co and Ni concentrations, together with their mutual ratios, provide a solid basis for distinguishing gabbro-hosted VMS mineralization from basalt- and sediment-hosted types of VMS mineralization in the study area. The distinctive trace element features of pyrite, in conjunction with its sulfur isotope signature, have been identified as a robust tool for the discrimination of gabbro-, basalt- and sediment-hosted VMS mineralization. [ABSTRACT FROM AUTHOR]

Global demand for critical raw materials, including phosphorus (P) and rare earth elements (REEs), is on the rise. The south part of Norway, with a particular focus on the Southern Oslo Rift region, is a promising reservoir of Fe-Ti-P-REE resources associated with magmatic systems. Confronting challenges in mineral exploration within these systems, notably the absence of alteration haloes and distal footprints, we have explored alternative methodologies. In this study, we combine machine learning with geological expertise, aiming to identify prospective areas for critical metal prospecting. Our workflow involves processing over 400 rock samples to create training datasets for mineralization and non-mineralization, employing an intuitive sampling strategy to overcome an imbalanced sample ratio. Additionally, we convert airborne magnetic, radiometric, and topographic maps into machine learning-friendly features, with a keen focus on incorporating domain knowledge into these data preparations. Within a binary classification framework, we evaluate two commonly used classifiers: a random forest (RF) and support vector machine (SVM). Our analysis shows that the RF model outperforms the SVM model. The RF model generates a predictive map, identifying approximately 0.3% of the study area as promising for mineralization. These findings align with legacy data and field visits, supporting the map's potential to guide future surveys. [ABSTRACT FROM AUTHOR]

A fungus, Acremonium strictum KR21-2, produces biogenic manganese oxides (BMOs) that can oxidize exogenous Mn2+ ions to form different BMO phases. When other guest ions are present during the BMO formation, it can strongly affect the mineralogical characteristics of the resultant BMO phase. The impact of coexisting Ni2+ ions on the mineralogy of BMO phases formed through enzymatic Mn(II) oxidation and its sequestration ability is not yet fully understood. To better understand it, repeated sequestration experiments were conducted using BMOs in Ni2+/Mn2+ binary, single Ni2, and single Mn2+ solution systems with a pH range of 6.0 to 7.5. It was observed that simultaneous sequestration of Ni2+ and Mn2+ was efficient, with irreversible Ni2+ incorporation at pH values above 7.0. The resultant BMO phases showed that Ni2+-bearing Mn oxides resembling feitknechitite (β-MnOOH) were developed through enzymatic Mn(II) oxidation. At pH values below 6.5, the turbostratic birnessite structure was maintained even in Ni2+/Mn2+ binary solutions, and subsequently, the Ni2+ sequestration efficiency was low. The pseudo-first-order rate constants of enzymatically inactivated BMOs for Mn2+ sequestration were two orders of magnitude lower than those of active BMOs, indicating the crucial role of the enzymes in precipitating Ni2+-bearing Mn oxide phases. These findings provide new insights into the mechanism of Ni2+ interaction with Mn oxide through microbial activity under circumneutral pH conditions. [ABSTRACT FROM AUTHOR]

High sulphidation (HS) mineralization and associated advanced argillic alteration have been intersected by three drill holes below the Grasberg porphyry Cu-Au deposit, known as the Gajah Tidur prospect. The prospect is located between 1,500-2,750 m level, in Grasberg District, Papua, Indonesia. The holes are of KL98-10-21, KL98-10-22, and GRD39-08 which intersected 3.4 Ma Gajah Tidur monzonite, Grasberg Igneous Complex, the wall rocks of Kembelangan, and New Guinea Limestone Group. This research aims to determine the characteristics of high sulphidation mineralization associated with advanced argillic alteration at Gajah Tidur. Petrographic, XRD, SEM, fluid inclusion, and XRF (geochemical) analyses were applied to identify the mineralogy, geochemistry, and ore fluid properties. The major element plots show a differentiated intrusion. The alteration consists of potassic materials composed of biotite and K-feldspar, overprinted by phyllic and advanced argillic ones typified by alunite, pyrophyllite, and kaolinite. The high sulphidation mineralization characterized by pyrite-covellite, chalcopyrite-chalcocite, enargite, and digenite is also present. Fluid inclusion homogenization temperature of mineralized quartz vein ranges from 393 to 542°C, indicating a magmatic fluid origin predominantly. Two distinct porphyry systems, consisting of the Gajah Tidur Cu-Mo and the Main Grasberg Cu-Au porphyry systems are emplaced at the Gajah Tidur level. Advanced argillic is less intense compared to a pervasive phyllic alteration, overprinting the stockwork and surrounding rocks, emplaced at the upper part of quartz stockwork. It is possibly associated with a late stage of Gajah Tidur porphyry hydrothermal fluids which became cooler and highly acidic. Similar to other porphyry systems such as Oyu Tolgoi in Mongolia, the Gajah Tidur porphyry did not have its hydrothermal fluid ascent to the surface to form lithocap. Instead, the ascending fluids cooled at shallower depths resulting in the formation of advanced argillic alteration. [ABSTRACT FROM AUTHOR]

Extreme learning Machine (ELM) is a novel supervised machine learning algorithm, which has the advantages of fast-learning speed, good generalization, high classification performance, and can avoid problems such as local minimum, unreasonable learning rate, excessive number of iterations and overfitting. However, its classification performance is affected by imbalanced training data. To solve this problem, the synthetic minority oversampling technique (SMOTE) was integrated with the ELM algorithm to construct a hybrid algorithm, called SMOTified ELM, to identify polymetallic mineralization anomalies from the 1: 50,000 drainage sediment survey data in the Yeniugou area of Tokexun County, Xinjiang, China. A comparison between the SMOTified ELM model and the ELM model shows that the SMOTified ELM model is superior to the ELM model in terms of receiver operating characteristic curves (ROCs) and area under the (ROC) curves (AUCs). The ROC curve of the SMOTified ELM model is closer to the upper left corner of the ROC space than that of the ELM model. The AUC value of the SMOTfied ELM model (0.963) is higher than that of the ELM model (0.898). The polymetallic mineralization anomalies identified by the SMOTified ELM model account for 10.61% of the study area and contain 100% of known polymetallic deposits. The polymetallic mineralization anomalies identified by the ELM model account for 8.00% of the study area and contain 89% of known polymetallic deposits. Therefore, the SMOTified ELM method is a potentially useful technique for building a supervised mineralization anomaly identification model with high performance. [ABSTRACT FROM AUTHOR]

In this study, trace iron-doped 3D urchin-like titanium dioxide (Fe–TiO 2) were prepared via a straightforward water bath process. The successful incorporation of trace iron into the TiO 2 structure was confirmed through detailed EDX, EPR, and XPS analyses. Moreover, the Fe–TiO 2 photocatalyst exhibited remarkable efficacy in degrading the targeted compound, trimethoprim (TMP), achieving an impressive degradation rate of 95.6 % within a concise 60-min timeframe and a captivating mineralization rate of 32.1 % within 120 min. These performance metrics outshone those of pristine TiO 2 by substantial factors of 1.9 and 1.2, respectively. Photoelectric characterization results also confirmed that Fe doping significantly enhanced the efficiency of charge carrier separation of TiO 2. Furthermore, the catalytic performance of Fe–TiO 2 remains essentially unchanged after a tenfold expansion in equal proportion using the water bath doping system. This confirms the practicality of the batch preparation approach for Fe-doped TiO 2. The Fe–TiO 2 catalyst consistently demonstrated efficient degradation capabilities across various water sources, ranging from natural river water to treated secondary effluents from sewage plants and tap water, further emphasizing its significant potential for practical applications. This comprehensive study provides fresh insights into the batch preparation of doped catalysts and their utility in mitigating water pollution. [ABSTRACT FROM AUTHOR]

Rare earth elements are critical constituents for modern technologies, and some of their largest natural resource deposits are related to carbonatite systems. However, the mechanisms leading to rare earth element mineralization and the role of magmatic fluids in carbonatite systems remain poorly understood. Here, we present the first in situ characterization of fluids and their trace-element compositions in natural carbonatite systems by studying secondary quartz-hosted fluid inclusions from Oldoinyo Lengai volcano. By comparing our data to other fluids and melts from various carbonatite systems, we constructed a model for fluid-mediated rare earth element transport and mineralization. We show that carbonatite-related fluids are rich in alkali-carbonate + sulfate + chloride and CO2, but poor in H2O, and they can be significant carriers of rare earth elements (>1600 ppm). We argue that fluid CO2 contents are essential to preclude or slow down the interaction with wall rock during migration and that fluid-mediated rare earth element mineralization occurs when partial pressure of CO2 decreases in the fluid (i.e., during degassing). [ABSTRACT FROM AUTHOR]

Soil organic nitrogen (N) mineralization not only supports ecosystem productivity but also weakens carbon and N accumulation in soils. Recalcitrant (mainly mineral‐associated organic matter) and labile (mainly particulate organic matter) organic materials differ dramatically in nature. Yet, the patterns and drivers of recalcitrant (MNrec) and labile (MNlab) organic N mineralization rates and their consequences on ecosystem N retention are still unclear. By collecting MNrec (299 observations) and MNlab (299 observations) from 57 15N tracing studies, we found that soil pH and total N were the master factors controlling MNrec and MNlab, respectively. This was consistent with the significantly higher rates of MNrec in alkaline soils and of MNlab in natural ecosystems. Interestingly, our analysis revealed that MNrec directly stimulated microbial N immobilization and plant N uptake, while MNlab stimulated the soil gross autotrophic nitrification which discouraged ammonium immobilization and accelerated nitrate production. We also noted that MNrec was more efficient at lower precipitation and higher temperatures due to increased soil pH. In contrast, MNlab was more efficient at higher precipitation and lower temperatures due to increased soil total N. Overall, we suggest that increasing MNrec may lead to a conservative N cycle, improving the ecosystem services and functions, while increasing MNlab may stimulate the potential risk of soil N loss. [ABSTRACT FROM AUTHOR]

Elucidating metal transport agents is the key to understanding the genesis of deposits and tracking the locations of concealed orebodies. Here, we integrate H-O-S-Cu isotopic data from the shear-zone-hosted Lingyun Cu deposit, China, as a means to fingerprint metal transport agents. Sulfide mineralization can be divided into early and late stages, which consist of chalcopyrite + bornite + quartz veins and chalcopyrite + bornite + ankerite veinlets, respectively. Both δ18Ofluid and δD values of fluid inclusions hosted by quartz (δ18Ofluid: 0.5‰ to 9.9‰, δD: –103.9‰ to –60.1‰) and δ65Cu values of sulfides (–1.85‰ to +0.39‰) from the early stage progressively decrease from the southeastern to northwestern portions of the Lingyun deposit, whereas sulfide δ34S simultaneously shifts toward heavier values (–14.4‰ to 5.0‰). The δ34S and δ65Cu values of sulfides from the late stage have restricted ranges from –11.2‰ to –9.3‰ and –0.30‰ to 0.05‰, respectively. The possibilities of meteoric water addition, water-rock interaction, inter-mineral Cu partitioning, diffusion, and oxidation could be ruled out as reasons for having caused systematic H-O-S-Cu isotope variations. Vapor-liquid separation resulted in preferential incorporation of light Cu, H, and O isotopes into the vapor phase. The decrease in oxygen fugacity in the fluids resulted in a shift toward heavier δ34S values as fluid flowed outward. Vapor-phases are the dominant transport agents for Cu in the Lingyun deposit, which may be widely applicable to shear-zone-hosted deposits. The direction of progressively increasing δ65Cu, δD, and δ18O values and decreasing δ34S values allows identification of potential locations of concealed orebodies. [ABSTRACT FROM AUTHOR]

A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou Province. The mineral that makes up the polymetallic layer is related to the sedimentary facies. To analyze the differentiation mechanism between polymetallic deposits (Ni‐Mo and V), the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of pyrite. The results show that δ34S values of pyrite vary widely from −7.8 ‰ to 28 ‰ in the Gezhongwu profile, while the δ34S values are relatively uniform (from 27.8 ‰ to 38.4 ‰) in the Haishan profile. The isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform; this indicates that the δ34SO42– values in seawater must be differently distributed in depositional environments. The sulfur in the Ni‐Mo layer is produced after the mixing of seawater and hydrothermal fluid, while the V layer mainly originates from seawater. Overall, the Ni‐Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid. [ABSTRACT FROM AUTHOR]

As improper processing and disposal of animal waste cause negative impacts on the environment, the animal industry sector must shift to more sustainable practices to lessen these effects. Recently, the application of the circular economy concept in agriculture, using animal waste as part of nutrient cycling, has emerged as a sustainable approach. The study aims to develop and test the small-scale integrated hydroponics-animal waste bioreactor (AWB) for romaine lettuce production using chicken manure tea (CMT) derived from dried chicken manure as a primary nutrient source. Three integrated hydroponics- AWB systems, with varying concentrations of CMT at 1,000 ppm, 1,200 ppm, and 1,400 ppm total dissolved solids (maintained within an upper and lower bound of 50 ppm), were constructed, tested, and compared to conventional hydroponics that used a nutrient solution maintained at 1,000 ppm TDS. The test result suggests that the ideal concentration of CMT in the system is 1,000 ppm. Within the optimum manure tea concentration, the small-scale integrated hydroponics-AWB produced romaine lettuce with growth parameters comparable to conventional hydroponics. In addition, increasing the CMT concentration to 1,400 ppm negatively impacts the plant growth parameters of romaine lettuce. The developed small-scale integrated hydroponics-AWB system provides a viable approach for growing lettuce using animal waste as the major source of nutrients. The developed production system could help mitigate the negative environmental effects of improper handling and disposal of animal waste and dependence on chemical-based nutrient solutions in hydroponic crop production. [ABSTRACT FROM AUTHOR]

Increasing amounts of greenhouse gases, such as CO2, released into the atmosphere have a profound impact on global climate change. Understanding how soil organic carbon (SOC) mineralization changes as a result of land‐use change can shed light on the mechanisms by which SOC mineralization occurs, thus illuminating pathways to achieve global C neutrality targets. Accordingly, the Grain for Green Project (GGP) on the Loess Plateau was used as the starting point to observe how microorganisms affect SOC mineralization through field sampling and laboratory incubation experiments. We found a significant increase in SOC mineralization rates resulting from the GGP, though only at the soil surface (0.47–6.40 mg·kg−1 soil·day−1). We also found that soil microorganisms had a significant effect on different types of C sources, and Proteobacteria and Ascomycota/Mortierellomycota were the dominant bacterial and fungal groups at the GGP sites. The factors limiting SOC mineralization varied with farmland conversion to other land‐use types, and the direct and interactive contributions of these factors were quantified. The explanatory power examined in terms of land‐use ability to directly predict SOC mineralization rates was as follows: farmland (0.82), grassland (0.76), shrubland (0.41), and forestland (0.29). Along the increasing vegetative complexity gradient from farmland to forestland, the individual variable explanatory values decreased, while the relative importance of the interactive effects between variables increased. Our research demonstrates that the GGP increased soil biological activity and improved microbial community ability to metabolize C sources, thereby accelerating SOC mineralization. This will provide a scientific basis for decisions to enhance global semidrought recovery. [ABSTRACT FROM AUTHOR]

This study investigated the use of heat-activated persulfate (HAP) as a chemical oxidation technique for removing tinidazole (TNZ) antibiotic from aqueous solutions. The impact of various operating parameters, including TNZ initial concentration (20 μM), persulfate (PS) initial dose (0.2–2 mM), solution pH (3–11), solution temperature (20–60 °C), and reaction time (10–120 min), was examined. The results indicated that sulfate radicals were the primary species responsible for TNZ degradation. Higher temperatures and PS concentrations improved the process, while higher pH values and TNZ initial concentrations slowed it down. Additionally, chloride and bicarbonate ions reduced reaction rates, with chloride ions having a more significant effect. Under optimal conditions (including [TNZ]0 = 20 μM, pH = 7, [PS]0 = 1 mM, temperature = 60 °C, and reaction time = 120 min), the removal efficiency achieved was 91.15%, with a mineralization rate of 85.8%. These results suggest that the process is relatively safe. The degradation of TNZ was best described by the pseudo-first-order model compared to other models. Additionally, the process was found to be exothermic and spontaneous, with a negative Gibbs free energy change indicating that it is thermodynamically feasible. The study found HAP to be an effective and cost-efficient technique for removing TNZ antibiotic due to its ease of operation and the absence of the need for additional chemicals or waste handling. Based on these findings, HAP can be considered an advanced oxidation technique for treating antibiotic-contaminated water. [ABSTRACT FROM AUTHOR]

The nitrogen (N) cycle, a major biogeochemical cycle in forest ecosystems, notably affects ecosystem multifunctionality. However, the magnitude and role of organic N and the snow season remain uncertain in this cycle. We assessed the N flux and pool data of a temperate deciduous broad-leaved forest to clarify N cycle processes. The results showed that the most important component of the N pool was the soil N pool. The N demand of the site amounted to 139.4 kg N ha−1 year−1 and was divided into tree production (83.8%) and bamboo production (16.2%). We clarified that retranslocation (37.4%), mineralization at a soil depth of 0–5 cm (15.3%), litter leachate (4.6%), throughfall (2.3%), and canopy uptake (0.5%) provided 60.1% of the N demand. In terms of soil at 0–5 cm in depth, the net mineralization rate during the snow season contributed to 30% of the annual mineralization. We concluded that the study site was not N-saturated as a result of a positive N input–output flux budget. More than half of the total N was accounted for by dissolved organic N flowing through several pathways, indicating that organic N plays a vital role in the cycle. The mineralization rate in the soil layer during the snow season is an important link in the N cycle. [ABSTRACT FROM AUTHOR]

Chloramphenicol, a broad-spectrum antibiotic employed for controlling bacterial infections, presents an intriguing aspect in terms of its environmental fate in soils. 14C-labeled chloramphenicol was used to explore its mineralization and residue characteristics in three distinct agricultural soils in China. The findings revealed a nuanced pattern in the fate of 14C-chloramphenicol, with notable variations among the different soils under investigation. The chloramphenicol extract residue exhibited a reduction of 18.04% in sandy clay soil, 23.04% in clay loam soil, and 21.73% in loamy clay soil. Notably, the mineralization rate in sandy clay soil was 25.22% surpassed that in the other two soils, particularly during the initial stages of incubation. Over time, the diminishing extract residue underwent conversion into minerals and bound residue. The formation rate of bound residue was increased from 44.59 to 53.65% after adding 10% manure, suggesting that chloramphenicol easily binds with soils rich in organic matter. The bound residue is predominantly localized in the humin fraction across all soils. Additionally, the sterilized soil experiments indicated the pivotal role of microorganisms in influencing the fate of chloramphenicol under the specified experimental conditions. In conclusion, this study offers valuable insights into the environmental dynamics of chloramphenicol in soils, emphasizing the importance of soil composition, organic matter content, and microbial activity. The findings contribute to a scientific understanding of the environmental safety implications associated with chloramphenicol usage. [ABSTRACT FROM AUTHOR]

Fabrication of mineralized materials through the nature‐mimicking dynamic biomineralization process has attracted great interest but remains a huge challenge till now. Here, a drug‐mineralized hydrogel (DMH) with spontaneous dynamic mineralization behaviors is reported, which highly mimics the dynamic mineralization process of natural tissues. The hydrogel is facilely fabricated via directly mixing sodium hyaluronate (HA) with alendronate sodium (ADA) and CaCl2 in deionized water. The resultant hydrogel possesses a white‐to‐semi‐transparent transition and a soft‐to‐hard transition during incubation at 37 °C. Mechanism studies reveal that the spontaneous dynamic change of the hydrogel is ascribed to the HA‐regulated dynamic mineralization of ADA/Ca2+ complexes, where amorphous ADA/Ca2+ complexes will gradually transform into mineral crystals with the prolongation of incubation time. Owing to the dynamic transformation process, the DMH shows excellent injectability and moldability at the initial stage. More importantly, the DMH exhibits a sustained release behavior of ADA in vitro, superior adhesiveness with bone, biodegradability, and good biocompatibility. As a result, the developed DMH demonstrates promising uses for accelerating bone repair in a rat cranial defect model. Overall, the research provides a general strategy to prepare drug‐mineralized hydrogels with spontaneous dynamic mineralization behaviors, which may find potential uses in various biomedical fields. [ABSTRACT FROM AUTHOR]

Composite materials based on gels and hydroxyapatite could provide promising characteristics for biomedical materials because of biocompatibility, osteointegration, and easy implementation. In this research, enzymatic synthesis of hydroxyapatite was studied as a technique for tissue engineering and scaffolds creation. The hydroxyapatite crystals were synthesized using this method and characterized with X-ray diffraction, electron microscopy, IR and Raman spectroscopy and analytical methods. As a result, a material with assumed composition of Ca 10− x (HPO 4) x (PO 4) 6− x (OH) 2− x /CaHPO 4 /CaCO 3 was obtained by enzymatic synthesis. The dynamics of size evolution, texture and crystallinity of the solid phase as a function of deposition time were also investigated. Afterwards, this method was used for gel mineralization with hydrogels such as agarose, alginate, gelatin, and polyacrylamide. Hydroxyapatite crystals obtained inside and above the hydrogels were analyzed with X-ray diffraction and electron microscopy. The particle diameter distribution functions were used to evaluate the mineralization in different gels. The shape and size of mineral inclusions depend on the density of the hydrogel grid. The localization of the formed solid phase depends on the nature of the gel and the concentration of alkaline phosphatase inside it. The results provide an opportunity to control the morphology of calcium phosphate particles produced during mineralization, which is important for the creation of biomedical materials with specified and reproducible characteristics. [ABSTRACT FROM AUTHOR]

Background: Hypertension-induced mechanical stress on vascular smooth muscle cells (VSMCs) is a known risk factor for vascular remodeling, including vascular calcification. Caveolin-1 (Cav-1), an integral structural component of plasma membrane invaginations, is a mechanosensitive protein that is required for the formation of calcifying extracellular vesicles (EVs). However, the role of mechanics in Cav-1-induced EV formation from VSMCs has not been reported. Results: Exposure of VSMCs to 10% mechanical stretch (0.5 Hz) for 72 h resulted in Cav-1 translocation into non-caveolar regions of the plasma membrane and subsequent redistribution of Cav-1 from the VSMCs into EVs. Inhibition of Rho-A kinase (ROCK) in mechanically-stimulated VSMCs exacerbated the liberation of Cav-1 positive EVs from the cells, suggesting a potential involvement of actin stress fibers in this process. The mineralization potential of EVs was measured by incubating the EVs in a high phosphate solution and measuring light scattered by the minerals at 340 nm. EVs released from stretched VSMCs showed higher mineralization potential than the EVs released from non-stretched VSMCs. Culturing VSMCs in pro-calcific media and exposure to mechanical stretch increased tissue non-specific alkaline phosphatase (ALP), an important enzyme in vascular calcification, activity in EVs released from the cells, with cyclic stretch further elevating EV ALP activity compared to non-stretched cells. Conclusion: Our data demonstrate that mechanical stretch alters Cav-1 trafficking and EV release, and the released EVs have elevated mineralization potential. [ABSTRACT FROM AUTHOR]

The Qinghai–Tibet Plateau, abundant in mineral resources, is a treasure trove for geological explorers. However, exploration has been hindered by the presence of dense vegetation, weathering layers, and desert cover, particularly in the North Qaidam region. As a result, there is an urgent need to develop efficient geochemical composition methods. In a study of stream sediment geochemical data from the Lüliangshan area of the North Qaidam, the log-ratio transformation was used for data processing, Robust Factor Analysis (RFA) was used for model construction, and the spectrum–area (S-A) model was used for anomaly separation. The outcomes identified two distinct groups of element combinations associated with mineralization. The first group consisted of Au + Ag + Pb + Sb + Hg linked to tectonic-altered rock-type Au (antimony) deposits, while the second group consisted of Cu + Zn + Co and was closely associated with Cu-Ni sulfide deposits. The S-A fractal filtering technique amplified weak anomalies and minimized the area of anomalies against strong backgrounds. The study successfully detected substantial Cu mineralization in the source areas of geochemical anomalies in the Lüliangshan region. Consequently, the log-ratio–RFA–S-A fractal model has been proven to be an effective combination of methods for identifying and extracting geochemical anomalies from stream sediment samples and for mineral exploration in covered areas. [ABSTRACT FROM AUTHOR]

Deep mineralization of low concentration toluene (C7H8) is one of the most significant but challenging reactions in photocatalysis. It is generally assumed that hydroxyl radicals (⋅OH) as the main reactive species contribute to the enhanced photoactivity, however, it remains ambiguous at this stage. Herein, a S‐scheme ZnSn(OH)6‐based heterojunction with AlOOH as water resistant surface layer is in situ designed for tuning the free radical species and achieving deep mineralization of C7H8. By employing a combination of in situ DRIFTS and materials characterization techniques, we discover that the dominant intermediates such as benzaldehyde and benzoic acid instead of toxic phenols are formed under the action of holes (h+) and superoxide radicals (⋅O2−). These dominant intermediates turn out to greatly decrease the ring‐opening reaction barrier. This study offers new possibilities for rationally tailoring the active species and thus directionally producing dominant intermediates via designing water resistant surface layer. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) mineralization is a key component of the global carbon cycle. Its temperature sensitivity Q10 (which is defined as the factor of change in mineralization with a 10 °C temperature increase) is crucial for understanding the carbon cycle-climate change feedback but remains uncertain. Here, we demonstrate the universal control of carbon quality-availability tradeoffs on Q10. When carbon availability is not limited, Q10 is controlled by carbon quality; otherwise, substrate availability controls Q10. A model driven by such quality-availability tradeoffs explains 97% of the spatiotemporal variability of Q10 in incubations of soils across the globe and predicts a global Q10 of 2.1 ± 0.4 (mean ± one SD) with higher Q10 in northern high-latitude regions. We further reveal that global Q10 is predominantly governed by the mineralization of high-quality carbon. The work provides a foundation for predicting SOC dynamics under climate and land use changes which may alter soil carbon quality and availability. [ABSTRACT FROM AUTHOR]

Combined straw and straw-derived biochar input is commonly applied by farmland management in low-fertility soils. Although straw return increases soil organic matter (SOM) contents, it also primes SOM mineralization. The mechanisms by which active microorganisms mineralize SOM and the underlying factors remain unclear for such soils. To address these issues, paddy soil was amended with 13C-labeled straw, with and without biochar (BC) or ferrihydrite (Fh), and incubated for 70 days under flooded conditions. Compound-specific 13C analysis of phospholipid fatty acids (13C-PLFAs) allowed us to identify active microbial communities utilizing the 13C-labeled straw and specific groups involved in SOM mineralization. Cumulative SOM mineralization increased by 61% and 27% in soils amended with Straw + BC and Straw + Fh + BC, respectively, compared to that with straw only. The total PLFA content was independent of the straw and biochar input. However, 13C-PLFAs contents increased by 35–82% after biochar addition, reflecting accelerated microbial turnover. Compared to that in soils without biochar addition, those with biochar had an altered microbial community composition-increased amounts of 13C-labeled gram-positive bacteria (13C-Gram +) and fungi, which were the main active microorganisms mineralizing SOM. Microbial reproduction and growth were susceptible to nutrient availability. 13C-Gram + and 13C-fungi increased with Olsen P but decreased with dissolved organic carbon and NO 3 - contents. In conclusion, biochar acts as an electron shuttle, stimulates iron reduction, and releases organic carbon from soil minerals, which in turn increases SOM mineralization. Gram + and fungi were involved in straw decomposition in response to biochar application and responsible for SOM mineralization. Highlights: Straw return accelerates microbial mineralization of SOM. Combined biochar and straw input raises SOM mineralization by 60%. Biochar addition increases 13C incorporation from straw into Gram + bacteria and fungi. 13C-Gram + bacteria and 13C-fungi are the dominant active microorganisms that mineralize SOM. [ABSTRACT FROM AUTHOR]

• CO 2 mineralization ability was investigated by typical alkaline solid wastes. • The mineralization products of steel slag present excellent effect on plant growth. • The promotion of plant cultivation was analyzed from the view of mass transfer. CO 2 mineral sequestration using alkaline solid waste (ASW) is a promising strategy for synergistically reducing CO 2 emissions and reusing industrial waste. However, improvement the carbonation degree still remains challenges due to the sluggish leaching rate of Ca/Mg ion at low pH. To the issues, this study proposed an amine-mediated CO 2 absorption and mineralization process with six common ASWs, as well an ecological utilization route of CO 2 -ASW productions. Experimental results indicated that calcium carbide slag (CS) had greater CO 2 mineralization capacity (86.2 g-CO 2 /kg-CS) than other ASWs, while stirring rate and particle size played a more important role during CO 2 capture. Amine-mediated CO 2 capture was verified to be more excellent with steel slag (SS) as mineral medium. When the MEA concentration was increased to 2 mol/L, the extraction efficiency of Ca2+ was increased by 35 %, leaded to the CO 2 removal efficiency significantly promoted from 49 % to 92 %. The characterization of structural morphology referred spherical aragonite or needle-bar calcite was dominant for the porous mineralization products (30.6 m2/g). High germination index of pea seed (112.1 % at a dose of 10 g/L) inferred the negligible toxicological effects of tiny MEA residue over SS mineralization products, after centrifugally washing treatment. Pea seeds cultivated with mineralized products after centrifugal washing can achieve a growth rate of about 4 mm/d. Overall, this work provides a feasible route to apply the porous CO 2 -ASWs production into water conservation in arid and sandy land. [ABSTRACT FROM AUTHOR]

A Net Smelter Return (NSR) is a mine's net revenues less off-site costs. Three procedures for computation of the NSR of polymetallic mineralization are in common use: calculated values, "soft" estimates, and "mine-specific" estimates. Calculated NSRs are the actual NSRs realized by a mine. The calculated NSR of a block of mineralization is not an inherent property of that mineralization: it will depend on who mines it. Calculated NSRs provide the basis for legal obligations such as financial reporting and royalty payments to outside parties. However, recipients of NSR royalties find it difficult to audit what they are paid. Thus, to avoid lawsuits, royalty payments should be based on Gross Revenues (GRRs) rather than NSRs. Soft estimates of NSRs, based on statistical analysis of comparable situations, can be used in exploration to clarify assays of complex mineralization. Mine-specific NSRs are increasingly used by mines to specify cut-off grades. However, NSRs were devised for accounting purposes and they cannot be used as the only basis for distinguishing ore from waste. This paper proposes that the use of "Net NSRs," which include on-site costs as well as off-site costs, would be preferable for grade control. The use of Net NSRs would also permit grade-control geologists to function as the mine gate-keepers: alert to changes in profitability and environmental and health issues, both at the mine and among the mine's neighbors and customers. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is one of the most abundant and essential nutrient elements for crop growth; however, it is often not available to plants in sufficient quantity. Organic amendment can enhance its availability in acid tropical soils. In this study, we investigated the effects of manure type on the pattern of P release in highly weathered tropical soils of contrasting lithology and mineralogy. Two fallow-land soils from Isinyi-Nando and UNN-Nsukka in southeastern Nigeria with antecedent Bray-2 available P of 3.73 and 20.83 mg kg‒1, respectively, were amended with poultry droppings, pig slurry and cattle dung at soil-manure mass ratio of 100:6 and incubated. They were sub-sampled at 0, 1, 2, 4, 8, 16 and 28 weeks of incubation. In the two soil types, the highest increases in soil pH and available P always occurred with poultry droppings, with P release peaking at 16 weeks. Manure-induced increases in available P were greater in the less oxide-rich Isinyi-Nando soil compared with the more oxide-rich UNN-Nsukka soil over the incubation duration, with lower values in the former than the latter without amendment (5.79 and 23.57 mg kg‒1, respectively) and across treatments (40.59 and 45.16 mg kg‒1, respectively). The P release patterns were defined more by increases and decreases in soil pH and organic carbon with incubation time, respectively, and less by soil aggregation. Poultry droppings could enhance P release around 16 weeks post-amendment of these soils. Further studies are needed on its synchronized bioavailability and the prospects of slow-mineralizing cattle dung beyond 28 weeks. [ABSTRACT FROM AUTHOR]

Bone fractures are common occurrence in clinical settings, creating a high demand for effective repair material. Unfortunately, limited graft availability, donor site morbidities, unpredictable clinical outcomes, immunologic reactions, infection risks, and geometrical mismatching concerns hampered tissue graft use and underscored the need for scaffolds for more effective bone reconstructions due to their tunable properties. Significant progress has been carried out in past decade in the fields of nanoceramics synthesis, bioconjugate chemistry, and composite material processing. This review outlines hierarchical structures and biology of bone tissue, materialistic components of scaffolds (bioceramics, polymers, bioactive drugs), featured scaffolding strategies (nanofibers, hydrogels, aerogels, bioprinting, and fiber-reinforced composite), and emphasis that hierarchical and physiochemical characteristics of bone should be used as an inspiration for scaffold design. This review discussed how differences in materiobiological aspects of scaffolds, such as polymer/bioceramic nanocomposite, mineralized nanocomposite, matrix-rich nanocomposite, 3D microenvironmental cues, pore space cues, mechanical cues, usage of physical stimulation (magnetic, electroactive, and photoactivated cues), surface cues (wettability, roughness, textured, and surface charge), and biointerface cues (cell--biomaterial interactions, cell-selective homing, and cell regulatory strategies) modulate cellular and biological response for bone tissue engineering. This study further outlines the challenges and benefits of integrating materiobiological cues of scaffolds for bone tissue engineering. [ABSTRACT FROM AUTHOR]

A rapid soil test for accurately estimating nitrogen (N) supply from soil organic matter would help turfgrass managers develop N fertilization programs. In this study, we tested the feasibility of using a quick test, mineralizable carbon (min‐C), to predict turfgrass growth and N uptake from sand‐based putting green soils. A 2‐year field experiment was conducted in Verona, WI, on four sand‐based research golf greens planted with creeping bentgrass. Nitrogen fertilizer was applied at 0, 10, and 20 kg ha−1 every 2 weeks as liquid urea during the growing seasons. Soil samples were collected at 0–5 cm and 5–10 cm and tested for min‐C by measuring the flush of CO2 following the rewetting dried soil, where the soil was rewetted at 50% water‐filled pore space and incubated at 25°C for 24 h. Min‐C was greater at the shallower soil depth, and unaffected by N rates that were applied. On‐site air temperature, soil moisture content, and estimated soil temperature were negatively related with min‐C, where r2 = 0.26–0.60 for air temperature, r2 = 0.32–0.71 for soil moisture content, and r2 = 0.16–0.53 for estimated soil temperature, indicating the test is quite sensitive to environmental conditions at the time of sampling. Furthermore, min‐C had weak positive to no relationship with creeping bentgrass growth rate (r2 = 0–0.17) and N uptake (r2 = 0–0.23) on sand‐based putting green, suggesting the test does not hold promise as a method for improving fertilizer decisions to these systems. Core Ideas: Soil mineralizable C was not predictive of creeping bentgrass growth or N uptake on sand‐based putting greens.Soil mineralizable C was substantially influenced by sampling depths on sand‐based putting green.Environmental variables including air temperature, soil temperature, and soil moisture affected soil mineralizable C of sand‐based putting greens. [ABSTRACT FROM AUTHOR]

Critical-sized bone defects, commonly encountered in clinical orthopedic surgery, present a significant challenge. One of the promising solutions is to prepare synthetic bone substitute materials with precise structural control, mechanical compatibility, and enhanced osteogenic induction performance, nevertheless the successful preparation of such materials remains difficult. In this study, a two-step technique, integrating an extrusion-based printing process with biomimetic mineralization induced by alkaline phosphatase (ALP), was developed. Initially, a pre-cured hydrogel of regenerated silk fibroin (RSF) with a small quantity of hydroxypropyl cellulose (HPC) and ALP was prepared through heating the mixed aqueous solution. This pre-cured hydrogel demonstrated thixotropic property and could be directly extruded into predetermined structures through a 3D-printer. Subsequently, the 3D-printed RSF-based materials with ALP underwent biomimetic in situ mineralization in calcium glycerophosphate (Ca-GP) mineralizing solution, utilizing the polymer chains of RSF as templates and ALP as a trigger for cleaving phosphate bonds of Ca-GP. The resulting 3D-printed RSF-mineral composites including hydrogel and sponge possessed adjustable compression modulus of megapascal grade and variable hydroxyapatite content, which could be controlled by manipulating the duration of the mineralization process. Moreover, these 3D-printed RSF-mineral composites demonstrated non-cytotoxicity towards rat bone marrow mesenchymal stem cells. Therefore, they may hold great potential for applications involving the replacement of tissues characterized by osteoinductivity and intricate structures. [ABSTRACT FROM AUTHOR]

Chronic kidney disease (CKD) mineral and bone disorder (MBD) comprises a triad of biochemical abnormalities (of calcium, phosphate, parathyroid hormone and vitamin D), bone abnormalities (turnover, mineralization and growth) and extra-skeletal calcification. Mineral dysregulation leads to bone demineralization causing bone pain and an increased fracture risk compared to healthy peers. Vascular calcification, with hydroxyapatite deposition in the vessel wall, is a part of the CKD-MBD spectrum and, in turn, leads to vascular stiffness, left ventricular hypertrophy and a very high cardiovascular mortality risk. While the growing bone requires calcium, excess calcium can deposit in the vessels, such that the intake of calcium, calcium- containing medications and high calcium dialysate need to be carefully regulated. Normal physiological bone mineralization continues into the third decade of life, many years beyond the rapid growth in childhood and adolescence, implying that skeletal calcium requirements are much higher in younger people compared to the elderly. Much of the research into the link between bone (de)mineralization and vascular calcification in CKD has been performed in older adults and these data must not be extrapolated to children or younger adults. In this article, we explore the physiological changes in bone turnover and mineralization in children and young adults, the pathophysiology of mineral bone disease in CKD and a potential link between bone demineralization and vascular calcification. [ABSTRACT FROM AUTHOR]

The Bayan-Uul porphyry Au-Cu-(Mo) deposit occurs within the Mongol–Okhotsk Orogenic Belt, which is a part of the Central Asian Orogenic Belt. To understand geotectonic, petrogenesis, mineralization, and ore-forming fluid evolution of the Bayan-Uul deposit, we report petrographic and geochemical analyses of host rocks, mineralogy of ores, and fluid inclusion characteristics. Based on petrographic and mineralogical analyses, Cu, Mo, and Au mineralization occurs as disseminated and sulfide-bearing quartz–tourmaline veins hosted within granodiorites, monzodiorites, and diorite porphyry and tourmaline breccia. Four main alteration assemblages are identified: potassic, phyllic, argillic, and quartz–tourmaline alteration. The ore mineralogy of quartz–tourmaline veinlets are classified into A-type veinlets (quartz + tourmaline + chalcopyrite + magnetite + pyrite ± electrum), B-type veinlets (quartz + tourmaline + molybdenum + chalcopyrite + pyrite), and C-type veinlets (quartz + tourmaline + pyrite ± chalcopyrite). Fluid inclusions are found in quartz–tourmaline veinlets consisting mainly of liquid-rich two-phase (L-type), vapor-rich two-phase (V-type), and solid-bearing multi-phase (S-type) inclusions. The homogenization temperatures for the fluid inclusions in A-type, B-type, and C-type veinlets range from 215 to 490°C, 215 to 500 °C, and 160 to 350 °C and their salinity varies from 5.4 to 43.5 wt.%, 16 to 51.1 wt.%, and 3.4 to 24.1 wt.% NaCl equivalent, respectively. Coexistance of (L-type), (V-type), and (S-type) inclusions support fluid boiling. The δ18O values of ore fluids from different mineralizing A-, B-, and C-type veins are 8.7‰, 10.9‰, and 8.4‰, respectively, and the δ34S values of sulfide minerals range from −1.4‰ to 5.3‰, which indicates magmatic origin. [ABSTRACT FROM AUTHOR]

Skarn Au deposits exist in the circum-pacific metallogenic belt. Interestingly, the Da'anhe Au deposit is the only independent skarn gold deposit in the Lesser Xing'an Range. To determine the metallogenic mechanism and prospecting potential of the Da'anhe deposit, we performed skarn mineralogy, fluid inclusion (FI) and H-O isotope analyses. The results show the following: (1) The Da'anhe deposit is a calcareous reduced skarn Au deposit that formed between an Early Jurassic gabbroic diorite and the Permian Tumenling Formation marble. Its metallogenic process includes five stages: the early skarn stage (Stage I1), late skarn stage (Stage I2), early quartz-sulfide stage (Stage II1), late quartz-sulfide stage (Stage II2) and quartz-carbonate stage (Stage II3). Gold precipitated in Stage II1 and Stage II2. (2) The initial ore-forming fluid was derived from magmatic water and featured a high temperature and intermediate to high salinity. After boiling and mixing, the fluid eventually changed to a low-temperature and low-salinity reducing fluid dominated by meteoric water. (3) The formation depth of the Au orebodies was 2.27–3.11 km, and the orebodies were later lifted to the surface (<500 m). The potential for finding skarn Au deposits in the study area is limited. (4) The distinctive nature of the ore-related magma (i.e., source, reducing conditions and high water content) was key to the formation of the Da'anhe skarn gold deposit. [ABSTRACT FROM AUTHOR]