Mineral Fluid Research Articles

Biomimetic composite gelatin methacryloyl hydrogels for improving survival and osteogenesis of human adipose-derived stem cells in 3D microenvironment

Gelatin methacryloyl (GelMA) hydrogels are used for stem cell encapsulation in bone tissue engineering due to their fast and stable photo-crosslinking. However, cell viability and ability to induce osteogenesis are reduced by reactive oxygen species (ROS) produced during the crosslinking reaction. In this study, we developed biomimetic nanoparticles (TMNs) by combining tannic acid (TA) and simulated body fluid (SBF) minerals, and used them to synthesize GelMA-based composite hydrogels for addressing those limitations. The optimal concentrations of TA and SBF were investigated to create nanoparticles that can effectively scavenge ROS and induce osteogenesis. The incorporation of TMNs into composite hydrogels (G-TMN) significantly enhanced the survival and proliferation of encapsulated human adipose-derived stem cells (hADSCs) by providing resistance to oxidative conditions. In addition, the ions that were released, such as Ca2+ and PO43−, stimulated stem cell differentiation into bone cells. The hADSCs encapsulated in G-TMN had 2.0 ± 0.8-fold greater viability and 1.3 ± 1.8 times greater calcium deposition than those encapsulated in the hydrogel without nanoparticles. Furthermore, the in vivo transplantation of G-TMN into a subcutaneous mouse model demonstrated the rapid degradation of the gel-network while retaining the osteoinductive particles and cells in the transplanted area. The increased cellular activity observed in our multifunctional composite hydrogel can serve as a foundation for novel and effective therapies for bone deformities.

Dredged Canals, Wetland Loss, and Legacy

AbstractThe direct effects of converting coastal wetlands to open water by dredging them can be magnified by indirect effects. For example, dredged canals allow for recovery of mineral fluids 1000 s of m belowground which may induce geological subsidence or faulting; the dredged material deposited at the surface creates levees that redirect overland water flows. These indirect factors may stress wetland plants enough so that additional wetland habitat is converted to open water as a result of longer intervals of wetland soil waterlogging and drying, sulfide toxicity, less organic matter and sediment accumulation, and greater erosion. We quantified the indirect effects by demonstrating a robust dose–response relationship between coastal land loss and canal density in the Mississippi and Niger river deltas over 5 decades. Importantly, the ratio of land loss to canal area increases with time—a legacy effect. Surface impediments to water movements rather than belowground subsidence are the dominant causal factor. We also found that flood protection levees on the main river channel did not significantly magnify the effect of dredging on wetland loss. The cumulative effect of these direct and indirect consequences in coastal Louisiana is enormous and continuing, equaling many tens of billions dollars annually. Understanding these effects supports the rejection of a hypothesis that regional river channel flood protection levees or fluid withdrawal is of greater importance than the local changes in wetland hydrology. Wetland restoration/mitigation of dredging impacts on these two coasts can be implemented at a relatively low cost and quickly if this paradigm of the causes of coastal wetland losses is adopted.

World-class amethyst-agate geodes from Los Catalanes, Northern Uruguay: genetic implications from fluid inclusions and stable isotopes

AbstractThe amethyst and agate geodes from the Los Catalanes Gemmological District in Uruguay represent one of the main deposits of its kind worldwide. The geometry of the deposit is horizontal, with an irregular distribution of amethyst geodes within the upper level of the basalt lava flows and shows strong variations in their abundance, as well as quality, geometry, and shape. Reliable exploration guides are scarce, and the limited knowledge of the geological parameters controlling its occurrence makes exploration unpredictable, leading to inaccurate reserve estimation. Based on cutting-edge methods including nucleation-assisted microthermometry of one-phase fluid inclusions and determination of triple oxygen isotope in silicates and carbonates, as well as analysis of geode-hosted water and groundwater, we estimate the crystallisation temperatures in the range between 15 and 60 °C. These low temperatures point to amethyst crystallisation after the emplacement of the complete basalt pile. The mineralising fluid shows isotopic signatures consistent with meteoric water and very low salinities from pure water up to rarely over 3 wt% NaCl-eq., likely sourced from the groundwater hosted in the aquifers in the basaltic sequence and underlying units. Based on the insights provided by the new data, we propose the combination of open- and closed-system crystallisation inside pre-existing cavities due to the episodic infiltration of meteoric water in a rather stable geological context.

Adsorption and retention of fracturing fluid and its impact on gas transport in tight sandstone with different clay minerals

To elucidate the adsorption characteristics and retention mechanisms of fracturing fluids in diverse clay minerals, we conducted on-line nuclear magnetic resonance (NMR) and atomic force microscopy (AFM) experiments. The depth and extent of solid phase damage are determined by the ratio between the size of fine fractions in fracturing fluid residue and the pore-throat size in experiments. Poor physical properties (K < 0.5 mD) result in a more preferential flow pathway effect during flowback, and the stepwise incremental pressure differential proves to be more effective for the discharge of fracturing fluid in submicron pore throats. The permeability is significantly influenced by the differential distribution of retained fracturing fluid, as supported by direct experimental evidence. The presence of good physical properties (K > 0.5 mD) combined with a scattered distribution of retained fracturing fluid is associated with high gas phase recovery permeability, whereas a continuous sheet-like distribution results in low recovery permeability. The expansive surface area and presence of filamentous illite minerals facilitate the multiple winding and adsorption of fracturing fluids, demonstrating strong hydrogen-bonding, multi-layering and multiple adsorption properties. The geological characteristics of the main gas formations exhibit significant variation, and the severity of damage caused by fracturing fluids occurs in diverse sequences. To address this issue, a differentiated strategy for optimizing fracturing fluids has been proposed.

The Permian Watershed tungsten deposit (northeast Queensland, Australia): fluid inclusion and stable isotope constraints

The Watershed scheelite deposit is located in an extinct fore-arc basin in the Mossman Orogen of North Queensland. This fore-arc region comprises multiply deformed, Ordovician–Silurian metasedimentary rocks of the Hodgkinson Formation, and it was intruded by Carboniferous–Permian granites of the Kennedy Igneous Association. At Watershed, the Hodgkinson Formation includes strongly deformed skarn-altered conglomerate, psammite and slate units, which record four deformation events that evolved from ductile (D1–3) to brittle–ductile (D4). Early, D1–2 scheelite mineralisation in Carboniferous monzonite and skarn-altered conglomerate formed during regional prograde metamorphism, which reached upper greenschist to lower amphibolite facies conditions. Permian, D4 scheelite mineralisation was deposited in transtensional, shear-related veins, vein haloes and skarn-altered conglomerate during retrograde, lower greenschist facies metamorphism. During D4, four stages of retrograde alteration (retrograde stages 1–4) affected the rocks. Fluid inclusion assemblages in retrograde stage 2, vein scheelite and quartz are characterised by a low-salinity H2O–NaCl ± CH4 fluid (XCH4 <0.01, 1.4–8.0 wt% NaCleq). The fluid inclusions show evidence for fluid mixing between a low (∼0 wt% NaCleq) and a medium (<8 wt% NaCleq) saline fluid. Scheelite mineralisation P–T conditions were determined at ∼300 °C and 1–1.8 kbar (i.e. a depth of 3.7–6.7 km), indicative of a high geothermal gradient (35–75 °C/km), which was likely caused by the heat from the Permian granites. The presence of pyrrhotite and arsenopyrite in D4 veins (retrograde stage 4), plus graphite and methane in the fluid inclusions in scheelite, indicates reduced mineralisation conditions. Oxygen isotope compositions (δ18OVSMOW) of retrograde stage 2 scheelite (+3.8 to +7.3‰), plagioclase (+7.0 to +11.8‰) and quartz (+12.6 to +15.5‰) indicate a fluid temperature of 306 ± 56 °C with δ18OVSMOW values between +4.7 and +8.3‰. Retrograde stage 3 muscovite δDVSMOW (−73.4 to −62.7‰) and δ18OVSMOW (+11.5 to +13.2‰) values were used to calculate the O–H isotopic compositions of the fluids in equilibrium with the minerals at various possible temperatures (250–300 °C). The results are consistent with a metamorphic origin for the mineralising fluid. Sulfur isotope compositions (δ34SCDT between −2.5 and +2.8‰) for vein-hosted, retrograde stage 4 sulfides indicate that sulfur could have come from seawater or seawater sulfate, which is consistent with the local geology, even though this range overlaps with magmatic sulfur isotope compositions. Metamorphic fluids probably originated from devolatilisation reactions in the Hodgkinson Formation during prograde metamorphism. Permian intrusions acted as heat source enhancing metamorphic fluid flow and metal transport.

Apparent Joint Swarms Formed by the Crack‐Jump Process

ABSTRACTJoint swarms can be important components of fractured reservoirs. They are often explained as damage around faults or related to mechanical differences between layers, although this does not explain the close spacing of the joints. Joint swarms around Bergen (Norway) are described, which are not related to exposed faults and are not influenced by layering or foliation in the Lower Palaeozoic gneisses. We suggest an evolution whereby: (1) a zone of microcracks develops; (2) one microcrack propagates and becomes connected to a source of mineralising fluid; (3) the fracture becomes a microvein, with a higher tensile strength than the microcracked host rock; (4) another microcrack propagates and the cycle is repeated, producing a zone of microveins; (5) the veins are partly weathered out, producing an apparent joint swarm, or the microveins crack at or near the ground‐surface. Joint swarms in exposed analogues may therefore not occur at reservoir depths.

Application of Nanofibrous Clay Minerals in Water-Based Drilling Fluids: Principles, Methods, and Challenges

Nanofibrous clay minerals, specifically palygorskite (Pal) and sepiolite (Sep), have been becoming a new generation of rheological additives for drilling fluid systems due to their unique nanostructure, high performance, environmentally benign nature, and cost-effectiveness. These nanoclay minerals exhibit excellent colloidal and rheological properties in aqueous systems, even in saline and high-temperature environments. Although Pal and Sep have been employed as auxiliary rheological additives in a few cases to enhance the salt resistance of conventional water-based drilling fluids (WBDFs), these two clay minerals have not yet been used on a large scale due to a lack of understanding of their structures and properties, as well as the control of their performance. This paper presents a comprehensive review of the clay mineralogy, colloidal chemistry, rheological behaviors, and filtration properties of nanofibrous clay minerals in WBDFs, with critical comments. It also discusses the challenges and prospects for further research. This review provides new insights into fundamental and applied studies of nanofibrous clay minerals and helps promote the large-scale application of nanofibrous clay products in drilling fluids.

Lithospheric resistivity structure of the Xuefeng Orogenic Belt and its implications for intracontinental deformation in South China

The Xuefeng Orogenic Belt (XFOB), located in the central part of the South China Block, is a typical Mesozoic intracontinental orogen in the central Jiangnan Orogenic Belt. By collecting magnetotelluric (MT) data across the XFOB, we obtained the resistivity structure of the lithosphere, which sheds light on the Mesozoic intracontinental orogenic processes in the XFOB. The resistivity structure reveals a low-resistivity body (<10 Ω∙m), beneath the XFOB, dipping southeast wards from a depth of 10 km to the bottom of the crust. This conductor is interpreted as a relic of the lower detachment zone, which coincides with low-density areas obtained from joint inversion of seismic models. It is believed to result from mineral fluids migrating along the thrust fault and squeezing sulfides into folds. Four low-resistivity bodies were identified at three extensional locations along the Jiangshan-Shaoxing Fault and at the Cili-Baojing Fault. The low-resistivity body (<10 Ω∙m) at the junction of the Shaoyang and the Hengyang Basin is located at the point where the Moho depth thins. The variation trend of the terrestrial heat flow values, with this low-resistivity body as the plate boundary, is consistent with the average variation of the terrestrial heat flow values within the block. We propose that the low-resistivity body under the Qidong-Yongzhou-Guilin fault conforms to the characteristics of the suture zone in the resistivity structure. Its existence indicates that the missing location of the Jiangshan-Shaoxing suture zone of the Yangtze and Cathaysia Block in the middle-southwest section of the South China Block is the Qidong-Yongzhou-Guilin fault. The Yangtze Block and the Hengyang Basin show high resistivity, the depth of which reaches 100 km and 40 km, respectively. Based on the resistivity model and geological data, the XFOB experienced Triassic compression, leading to basement decollement, thrusting, and nappe structures due to low-angle Paleo-Pacific Plate subduction. This compression also led to the uplift of the orogenic belt. Moreover, under the tension caused by the high-angle retreat of the Paleo-Pacific Plate, the Cretaceous extensional tectonics led to detachment along the thrust faults, forming half-graben and basin structures along the margins.

Migration and focusing of porphyry deposit-forming fluids through aplitic mush of the Saginaw Hill cupola, Arizona, United States

Porphyry-type Cu ± Au ± Mo deposits form in the upper (ca. 2–5 km deep) parts of large, long-lived magmatic-hydrothermal systems in which mineralising fluids are thought to be derived from mid-to shallow-crustal magma chambers. Increasingly, however, magmatic systems are viewed as consisting of mush with minor and transient lenses of magma, with mush being a variably packed framework of crystals with interstitial melt and magmatic volatile phase (MVP). In this context, questions remain as to the source (mainly depth) and mechanisms of transport and focussing of the vast volumes of fluids required for shallow level porphyry-type mineralisation. Even more problematic is a paucity of first-order textural evidence for the presence of mush in magmatic-hydrothermal systems, including those which host porphyry-type deposits. To address this, we have studied the aplitic porphyry cupola of the Saginaw Hill magmatic system, Tuscon, Arizona, United States, where magmatic-hydrothermal features are exceptionally well exposed, including a massive silica cap, quartz unidirectional solidification textures (USTs), stockworks of multiple generations of variably mineralised quartz veins and mineralised miarolitic cavities. From field-to micro-scale textural and geochemical studies, particularly observations of vermiform quartz between earlier generations of magmatic quartz and feldspar, we evidence the development of fluid pathways through mush at the magmatic-hydrothermal transition. These are shown to connect and provide fluids and ore constituents to the mineralised miarolitic cavities and early quartz vein stockworks. We suggest that this process should be considered in all new genetic, exploration and numerical models for porphyry and similar types of magmatic-hydrothermal ore-deposits.

Hydrothermal enrichment of rare earth elements in the Lower Permian Lijiatian bauxite deposit, southern China

Bauxite deposits are an important source of Al and also host a variety of critical metals, including rare earth elements (REEs). However, the parent rocks of bauxite deposits generally have low REE contents, leading to uncertainty over the REE sources and enrichment mechanisms. In this study, we report high REE (2095 ppm; Ce = 1340 ppm) contents in the Lijiatian bauxite deposit in Luxi County, western Hunan Province, South China. The Lijiatian bauxite deposit is the largest deposit in Hunan Province, with a total Al resources exceeding 7 × 106 tons. The ore-bearing strata in the lower Permian Liangshan Formation (ca. 275 Ma) are comprised a 3–5-m-thick bauxite layer (bauxite ore/clay) and an underlying 4–8-m-thick Fe layer (Fe ore/Fe-rich clay). The high REE contents in the bauxites can be attributed to the widespread presence of bastnäsite. The bastnäsite commonly coexists with authigenic chlorite, which formed at temperatures of 221–285 °C, indicative of a hydrothermal origin. Uranium–Pb dating of the bastnäsite yielded an age of 141.4 ± 7.0 Ma, indicating a hydrothermal overprint occurred during the Early Cretaceous, which resulted in the enrichment of REEs in the bauxites. The high contents of REEs, Ba, and P in the Cambrian Niutitang Formation black shales indicate it was a potential source of these elements for bastnäsite and coexisting barite and apatite. The deep-seated hydrothermal fluids (enriched in HF, CO2, and H2S) associated with the late Yanshanian extensional tectonic event in South China (155–123 Ma) ascended along fractures. The ascending fluids interacted with the black shales, extracting REEs, Ba, and P. When the fluids reached a certain depth, they mixed with the infiltrating basinal waters to form a mineralising fluid. The fluid then migrated towards the bauxite layers, underwent cooling and depressurisation, and precipitated bastnäsite, barite, apatite, and chlorite. We propose that a hydrothermal event led to the enrichment of REEs in the bauxites in Hunan Province. Considering the scarcity of REEs in the parent rocks of bauxites worldwide, hydrothermal activity likely has a key role in REE enrichment in bauxites.

Results of biochemical and histological studies after restoration of bone defects using cellular technologies in dental patients

Objective of the research was to find out the effectiveness of the use of osteoplastic materials based on the multipotent mesenchymal stromal cells of the adipose tissue during surgical treatment for restoration of bone defects in dental patients. The clinical material included examination of 79 patients who underwent replacement of bone defects of the alveolar processes and/or an alveolar part of the appropriate jaw by means of different osteoplastic materials and their combinations or without their application (the control group). Acid phosphatase activity in the oral fluid of patients was determined by means of the unified “end point” method. Alkaline phosphatase activity in the oral fluid was determined using a set of reagents produced by the company “Filisit-Diagnostika” (Ukraine). Oral fluid mineralization index (MI) of patients was calculated according to the ratio of enzymatic activity of alkaline phosphatase (ALP) to acid phosphatase (AP) according to the formula: MI=ALP/AP. Histological material was taken at the stage of installation of a dental implant. It was established that the use of a composition based on multipotent mesenchymal stromal cells of adipose tissue, platelet-enriched blood plasma and bone tissue substitute containing hydroxyapatite contributes to the improvement of regenerative processes in the bone tissue of the jaws, which is confirmed by a 28.68% decrease in acid phosphatase activity, an increase by 25, 97% of alkaline phosphatase activity in the oral fluid of group B patients and, accordingly, a 77.08% increase in the ratio of alkaline to acid phosphatase. According to the results of histological studies and phase-contrast microscopy, after 6-8 months of observation, in patients of group B, the areas of jaw defects were filled with newly formed bone tissue, identical to native bone, and the resulting trepanobioptas had the structure of cancellous bone with osteoblastic elements forming a chain around osteoid tissue. Having analyzed the results of biochemical and histological studies it was established that application of an osteoplastic composition based on the multipotent mesenchymal stromal cells of the adipose tissue, bone tissue substitute with hydroxyapatite and platelet-rich plasma allows restoration of bone defects of the alveolar processes and an alveolar part of the appropriate jaw in shorter terms. The method is an optimal alternative to traditional osteoplastic materials to be used in modern dental practice and dental implantation.

Investigation of the Effect of Mutual Diffusion on Hydrodynamic Parameters under Fluid Displacement

Formation of stagnant zones in a reservoir is mainly determined by differences in the flow velocity of fluids in heterogeneous micro and macro porous media. Additional resistance forces to fluid flow, which are of a different nature, result in a decrease in flow velocity. Forces arising from the diffusion of fluids with different physical-chemical characteristics and acting in different directions are one such class of the above-mentioned drag forces. An increase in the degree of fluid mineralization is capable of causing changes in the flow of a continuous diffusion layer. The mathematical solution of the problems considered in the study was solved using the "Matlab" program using the Finite Difference Method. The paper presents the results of displacement studies in porous media under the assumption that the flow characteristics of displacing and displaced fluids can be controlled. Theoretical and experimental substantiations showing the effect of diffusion process in fluids on flow properties have been carried out in the displacement process. The theoretical solution and modelling of concentration change in flow of mutually soluble dispersed solutions were presented. The effect of diffusion on the flow velocity in the process of displacement of mutually soluble liquid mixtures has been evaluated.

Associations between caries experience and oral fluid mineral content among patients in Arctic Russia: a study in the Nenets Autonomous Area

The relationship between the intensity of caries and mineral composition of oral fluid in adolescents in the Arctic zone of Russia was investigated using the example of the Nenets Autonomous Okrug. This study included 171 healthy boys and girls aged 15–17 years. The intensity of caries was assessed using the index caries + fillings + extracted permanent teeth and its components. Unstimulated oral fluid was collected into sterile tubes. Sodium, potassium, magnesium, phosphorus, and total and ionized calcium content and pH were examined in the oral fluid. Considering the pronounced right-sided asymmetry of the components of the index caries + fillings + extracted permanent teeth, calculations were performed using Poisson regression models. Results were presented as relative risks with 95% confidence intervals and as tests for trend. The prevalence of caries in the sample population did not differ by sex and was 87.8% for boys and 93.3% for girls (p = 0.221). On average, 1.8 carious teeth per person were detected in boys and 1.4 in girls (p = 0.021). No differences were found in the number of filled (p = 0.167) and extracted (p = 0.981) teeth. Additionally, the total sodium content in oral fluid was directly proportional to the index of caries + fillings + extracted permanent teeth (p = 0.040) and number of carious teeth (p 0.001). The total oral fluid calcium was significantly associated with both the caries + fillings + extracted permanent teeth index (p = 0.019) and number of filled teeth (p = 0.001). Inverse relationships were found between the number of filled teeth and magnesium (p = 0.028) and phosphorus (p = 0.037) content. The study showed the presence of statistically significant relationships between the mineral composition of oral fluid and index of caries + fillings + extracted permanent teeth and its components. Thus, unfavorable living conditions in the Arctic zone provide additional risk factors for the occurrence of dental diseases. The results of the study, if confirmed in other populations, can be used to develop models for predicting the development and progression of caries in adolescents of the Far North. Further studies of the mineral composition of oral fluid are required to obtain more complete clinical and laboratory data, considering confounding factors such as nutrition and type of filling material.

In Situ Geochemical Evaluation of Retrograde Hydration Effects in the Peri-Siberian Forearc Mantle (Khara-Nur and Alag-Khadny Peridotite Complexes)

In order to assess the geochemical effects of retrograde metamorphic rehydration, fluid metasomatism, and the fluid-mobile elements (FMEs) budget in the case of oceanic and continental subduction, we report the petrography, bulk, and in situ LA-ICP-MS trace-element data for the two poorly studied ophiolites in the northern (Khara-Nur, Eastern Sayan, Russia) and central (Alag-Khadny accretionary wedge, SW Mongolia) parts of the peri-Siberian orogenic framing. Both complexes are relics of the ancient oceanic mantle, which was subjected to processes of partial melting, metasomatism, and retrograde metamorphism. Typical mineral assemblages include olivine + orthopyroxene + chlorite + tremolite ± secondary olivine (640–800 °C), olivine + antigorite ± secondary clinopyroxene (&lt;640 °C), and olivine + chrysotile ± secondary clinopyroxene (&lt;250 °C) and are stable at pressures up to 2 GPa. Hydration and partial serpentinization of mantle peridotites lead to tremolite formation after orthopyroxene, followed by olivine replacement by antigorite. Serpentine-group minerals (antigorite and chrysotile) were distinguished by Raman spectroscopy, and the contents of incompatible elements (mobile and immobile in fluids) in metamorphic minerals (tremolite, antigorite, and chrysotile) were examined in situ by LA-ICP-MS. The behavior of conservative HFSE (Zr, Nb, Ta, and Ti) and—in part—HREE does not distinguish between the two types (oceanic and continental) of subduction environments. Different patterns of FMEs (Cs, Rb, Ba, U, Sb, Pb, Sr, and LREE) enrichment in metaperidotites reflect variations in the slab fluid composition, which was primarily governed by the contrasting nature of subducted lithologies. The affinity of Alag-Khadny to the subduction of a continental margin is recorded by increased FME contents and selective enrichment by some moderately mobile elements, such as U, Th, and LREE, with respect to the oceanic-type subduction environment of Khara-Nur. Distinct patterns of FME enrichment in tremolite and antigorite from two complexes indicate different sequences of fluid-induced replacement, which was controlled by Opx composition. We demonstrate that evaluation of the initial composition of precursor minerals affected by multi-stage melting and melt metasomatism should be considered with care to estimate the differential fluid overprint and associated elemental uptake from subduction fluids.

Application of Airborne Magnetic Data to Assess the Structures that Favour Gold Mineralization within Southern Parts of Katsina State, Nigeria

The Nigerian schist belts are endowed with gold mineralisation and to delineate the geological structures that favour gold mineralisation, the airborne magnetic data that cover the study area was employed. Also, the residual magnetic anomaly data of the research area was reduced to the Equator (RTE) followed by the application of the centre for exploration targeting (CET) plug-in and three source edge mapping techniques; analytic signal (AS), first vertical derivative (FVD) and the horizontal gradient magnitude (HGM), for structural delineation and subsequently the structural density map of the area was produced. Structural density varies from 0.186 km/km2 low to 0.93 km/km2 high. Portions within the study area with high structural densities are Bakori in the southwest, Shanono in the northeast, Gwarzo situated directly south of Shanono, north and south of Karaye, the border between Kafur and Rogo in the south, all within the schist. Since structures are conduits for the migration of mineralisation fluids, areas with high structural densities will be viable for gold mineralisation. Also, comparing the structural density map of the area to the analytic signal map of the area has revealed the high structural density portions to coincide with the high analytic signal zones. This implies that structures within these portions are responsible for the migration of mineralization fluid into these environments.

Preparation of black phosphorus@sodium alginate microspheres with bone matrix vesicle structure via electrospraying for bone regeneration

Bone matrix vesicles are commonly acknowledged as the primary site of biomineralization in human skeletal tissue. Black phosphorus has exhibited favorable properties across various chemical and physical domains. In this investigation, a novel composite microsphere was synthesized through the amalgamation of sodium alginate (ALG) with black phosphorus nanosheets (BP) utilizing the electrospray (ES) technique. These microspheres were tailored to mimic the regulatory function of matrix vesicles (MV) upon exposure to a biomimetic mineralization fluid (SBF) during the biomineralization process. Results revealed that black phosphorus nanosheets facilitated the generation of hydroxyapatite (HA) on the microsphere surface. Live-dead assays and cell proliferation experiments showcased a cell survival rate exceeding 85 %. Moreover, wound healing assessments unveiled that M-ALG-BP microspheres exhibited superior migration capacity, with a migration rate surpassing 50 %. Furthermore, after 7 days of osteogenic induction, M-ALG-BP microspheres notably stimulated osteoblast differentiation. Particularly noteworthy, M-ALG-BP microspheres significantly enhanced osteogenic differentiation of osteoblasts and induced collagen production in vitro. Additionally, experiments involving microsphere implantation into mouse skeletal muscle demonstrated the potential for ectopic mineralization by ALG-BP microspheres. This investigation underscores the outstanding mineralization properties of ALG-BP microspheres and their promising clinical prospects in bone tissue engineering.

Water–Rock Interaction Processes in Tíscar and Larva Active Faults (Betic Cordillera, SE Spain)

A hydrochemical and mineral study of groundwaters and damaged rocks from the Tíscar and Larva fault zones (Betic Cordillera, Iberian Peninsula) was carried out in order to (a) describe the physical and chemical properties of the groundwaters; (b) recognize significant locations with deep-origin fluids related to active tectonics; (c) and to describe the water–rock interaction and the neoformation of clay mineral processes and their importance in the seismicity of the faults. A sampling campaign was completed between November 2012 and November 2013, during which data were obtained from 23 different groundwater sites in the fault areas. Two main groups of waters were distinguished: (a) Ca2+-Mg2+-HCO3− facies characterized by poor conductivity and salinity; and (b) saline waters (up to 30 meq/L) rich in Ca2+-Mg2+-SO4-Cl− and with an elevated conductivity (frequently &gt; 1000 μS/cm). In addition, a minor group of saline and warm waters (T &gt; 16.5 °C) was found to be Na+-rich and show moderately high B values (&gt;0.33 ppm), and which mig ht be hosted in aquifers deeper than the two main groups. This group of deep-origin waters is oversaturated in clay minerals and is in equilibrium for Ca-Mg carbonate minerals. X-ray diffraction and scanning and transmission electron microscopy data corroborate the crystallization forecast of authigenic smectite, which appears as thin films coating carbonate fragments. The origin of smectite is related to the fragile strain and thermal–fluid–mineral interactions in fault rocks. Smectite could lubricate carbonate rocks, which favor creep deformation versus seismic slip. This work provides locations where groundwater physico-chemical properties and composition suggest tectonic fault activity.

Genesis of Pb–Zn Mineralization in the Pulang Cu Polymetallic Deposit in Yunnan Province, China: Insights from Analyses of Geology, Fluid Inclusions and C–H–O–S Isotopes

The Pulang super-large porphyry Cu polymetallic deposit, located in the Sanjiang area of Yunnan Province, is one of the largest Cu deposits in China. This deposit hosts Cu resources of ~5 × 106 t and other ore-forming elements, such as Mo, Au, Ag, Pb, Zn, Pt and Pd. Recently, obvious hydrothermal vein-type Pb–Zn mineralization, with a Pb + Zn resource of ~0.4 × 106 t, has been detected in the North Ore Section of the deposit. However, the genesis of these Pb–Zn ore bodies, especially their relationship to the major Cu ore bodies in the South Ore Section, remains controversial. We conducted geologic description, fluid inclusion petrography and microthermometry, and C, H, O and S isotope studies to uncover the genesis of Pb–Zn vein-type mineralization in North Pulang. As a result, three types of Pb–Zn veins were identified: a quartz–pyrrhotite–chalcopyrite–sphalerite–galena vein, a quartz–pyrrhotite–sphalerite–galena vein, and a calcite–quartz–pyrrhotite–galena vein. All fluid inclusions in the quartz from different veins are liquid-rich inclusions, with homogenization temperatures in the range of 184 °C–235 °C and salinities between 10.4 wt.% and 17.8 wt.% NaCl eq., indicating that the Pb–Zn ore-forming fluid was a single-phase fluid with a low temperature and low-to-medium salinity. Hydrothermal quartz in different stages displays δDwater values ranging from −46.9‰ to −120.0‰ (V-SMOW), and the calculated δ18Owater values range from 2.4‰ to 4.3‰ (V-SMOW), implying that the mineralization fluids likely originated from magma, with a minor involvement of meteoric water. The δ13CCal values (−2.3‰ to −7.9‰ V-PDB) of calcite indicate that C likely originated from a deep-seated source. The δ34S values of chalcopyrite, pyrite, pyrrhotite and sphalerite reveal that S was possibly derived from magmatic rocks. Based on the above data, it is suggested that the Pb–Zn mineralization in North Pulang was the result of the northward migration of ore-forming fluids that originated from South Pulang along the NE-trending structural fractures. A strong water–rock interaction occurred during the migration process. However, the involvement of meteoric water and accompanied cooling of fluids were most likely responsible for the precipitation of galena and sphalerite.

Sublithospheric Diamonds: Plate Tectonics from Earth's Deepest Mantle Samples

Sublithospheric diamonds and the inclusions they may carry crystallize in the asthenosphere, transition zone, or uppermost lower mantle (from 300 to ∼800 km), and are the deepest minerals so far recognized to form by plate tectonics. These diamonds are distinctive in their deformation features, low nitrogen content, and inclusions of these major mantle minerals: majoritic garnet, clinopyroxene, ringwoodite, CaSi perovskite, ferropericlase, and bridgmanite or their retrograde equivalents. The stable isotopic compositions of elements within these diamonds (δ11B, δ13C, δ15N) and their inclusions (δ18O, δ56Fe) are typically well outside normal mantle ranges, showing that these elements were either organic (C) or modified by seawater alteration (B, O, Fe) at relatively low temperatures. Metamorphic minerals in cold slabs are effective hosts that transport C as CO3 and H as H2O, OH, or CH4 below the island arc and mantle wedge. Warming of the slab generates carbonatitic melts, supercritical aqueous fluids, or metallic liquids, forming three types of sublithospheric diamonds. Diamond crystallization occurs by movement and reduction of mobile fluids as they pass through host mantle via fractures—a process that creates chemical heterogeneity and may promote deep focus earthquakes. Geobarometry of majoritic garnet inclusions and diamond ages suggest upward transport, perhaps to the base of mantle lithosphere. From there, diamonds are carried to Earth's surface by eruptions of kimberlite magma. Mineral assemblages in sublithospheric diamonds directly trace Earth's deep volatile cycle, demonstrating how the hydrosphere of a rocky planet can connect to its solid interior. ▪Sublithospheric diamonds from the deep upper mantle, transition zone, and lower mantle host Earth's deepest obtainable mineral samples.▪Low-temperature seawater alteration of the ocean floor captures organic and inorganic carbon at the surface eventually to become some of the most precious gem diamonds.▪Subduction transports fluids in metamorphic minerals to great depth. Fluids released by slab heating migrate, react with host mantle to induce diamond crystallization, and may trigger earthquakes.▪Sublithospheric diamonds are powerful tracers of subduction—a plate tectonic process that deeply recycles part of Earth's planetary volatile budget.

Towards a Model-Based Interpretation of Measurements of Mineralogical and Chemical Compositions

We introduce a new methodology for inference of fluid composition from measurements of mineralogical or chemical compositions, expanding upon the use of reactive transport models to understand hydrothermal alteration processes. The reactive transport models are used to impute a latent variable explanatory mechanism in the formation of hydrothermal alteration zones and mineral deposits. An expectation maximisation algorithm is then employed to solve the joint problem of identifying alteration zones in the measured data and estimating the fluid composition, based on the fit between the mineral abundances in the measured and predicted alteration zones. Using the hydrothermal alteration of granite as a test case (greisenisation), a range of synthetic tests is presented to illustrate how the methodology enables objective inference of the mineralising fluid. For field data from the East Kemptville tin deposit in Nova Scotia, the technique generates inferences for the fluid composition which compare favourably with previous independent estimates, demonstrating the feasibility of the proposed calibration methodology.