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Weathering crusts after granites are the most important source of heavy rare-earth elements (HREE) worldwide. Although HREE in these deposits is known to be inherited from parental rocks, the origin of HREE enrichment and the reasons why it is rare outside of China remains unclear. Here, we report the occurrence of variably organized nanoparticles of Ce-poor (

The rare earth elements (REE), and in particular neodymium and dysprosium, are essential for the development of renewable energy. At present the REE are sourced from either low concentration weathered granitoid (ion adsorption clay) deposits in southern China, or from high concentration carbonatite-related deposits [1], especially the World’s dominant REE mine at Bayan Obo, China, but also including the Mt Weld weathered carbonatite, Australia. Weathered carbonatites (e.g. Tomtor, Russia; Mount Weld, Australia) are some of the world’s highest grade REE deposits. As part of the NERC Global Partnerships Seedcorn fund project WREED, we have carried out preliminary investigations in weathering products from carbonatite hosted REE deposits. Three end member deposit styles can be identified – in situ residual deposits, where carbonate dissolution has generated primary REE mineral enrichment on palaeosurfaces or in karst; supergene enrichment from dissolution and reprecipitation of REE phosphates and fluorcarbonates forming hydrated phosphates or authigenic carbonate minerals; clay and oxide caps (either from in situ weathering or from soil transport from surrounding rocks) that may hold the REE adsorbed to mineral surfaces (c.f. the ion adsorption deposits). High grade weathered carbonatite deposits typically consist of supergene horizons, that may be phosphate-rich due to dissolution and re-precipitation of apatite and monazite during the weathering process (Mount Weld [2][3]), overlain by later sediments that may be REE enriched by accumulation of residual minerals (e.g. Tomtor [4]). The mineralogy of the ore zone is linked to, but distinct from, the unweathered carbonatite rock, and includes phosphates, crandallite-group minerals, carbonates and fluorcarbonates and oxides. We have carried out leaching studies, SEM examination and XPS characterisation of soil and weathered rock samples from a range of deposits. Residual and supergene processes can result in enrichments up to 100x times bedrock concentrations, with residual enrichments in particular hosted in monazite and bastnäsite. Supergene enrichment results in more complex mineralogy which may present processing challenges. Clay-rich soils have much lower REE concentrations. However, sequential leaching studies demonstrate that a significant proportion of REE are present at trace levels in the oxide fraction in residual and supergene deposits. In clay caps the easily leachable fraction of REE matches that of ion adsorption deposits and may represent a potentially easily extractable resource. References[1] Wall and Chakhmouradian, 2012, Elements 8, 333-340;[2] Duncan and Willett, 1990, Geology of Mineral Deposits of Australia pp. 591-597;[3] Lottermoser, 1990, Lithos 24, 151-167;[4] Kravchenko and Pokrovsky, 1995, Econ. Geol. 90, 676-689

Magnetite (Fe3O4) is one of the most common accessory minerals in magmatic rocks, and it can accommodate a wide variety of major, minor and trace elements that can be measured by laser ablation ICP-MS. In this study, we investigate the chemical compositions of magnetite from four carbonatite complexes (Oka, Mushgai Khudag, Hongcheon and Bayan Obo). The minor elements (Mg, Ti, Al, Mn) in magnetite vary significantly both within and between different complexes. High field strength elements (Zr, Hf, Nb, Ta, U, Th) are generally depleted in magnetite from carbonatite complexes, whereas K, Rb, Cs, Ca and P are commonly below detection limits. V and Zn display significant variations from tens to thousands of ppm. Co, Ni and Ga are present in ppm or tens of ppm, whereas Cu, Sr, Y, Ba and Pb are characterized by sub-ppm levels. Mo and Ge are identified at the ppm level, whereas a consistent concentration of 2–5 ppm is observed for Ge. The determined chemical compositions of magnetite from carbonatite complexes are quite distinguishable compared to those formed in silicate and sulfide melts. This is clearly shown using multielement variation diagrams, and the distinct signatures of carbonatite-related magnetite include strong positive anomalies of Mn and Zn and negative anomalies of Cu, Co and Ga. The discriminant diagrams of Ti vs. Zr + Hf, Ti vs. Nb + Ta and Ni/Cr vs. Ti are applicable for distinguishing magmatic and hydrothermal magnetite in carbonatite-related environments. In addition, the discriminant diagram of Zn/Co vs. Cu/Mo and Cu vs. Zr + Hf can be used to distinguish carbonatite-related magnetite from magnetite that formed in other environments.

This study was carried out in order to find a possible use for waste produced during the processing of vegetables and maize. Anaerobic fermentation is a suitable way to handle this wet and easily biodegradable organic material. The aim of this study was to evaluate the impact of waste corn kernels, peas, crushed corn kernels, French beans, mixed vegetables (broccoli, cauliflower, peas and carrot), corn leaf and corn husk on anaerobic fermentation. Anaerobic fermentation tests was carried out in batch fermenters (5 dm3) for 21 days at 42 °C. During this period the quantity and quality of biogas produced were monitored. The following substrate parameters were determined: dry matter content, organic dry matter content, nutrients content (protein, fat, fibre, starch, acid detergent fibre, neutral detergent fibre) and elemental composition. The hypothesis predicting the inhibitory impact of substrates on the anaerobic process was not confirmed. Biogas production after 21 days of hydraulic retention time ranged from 0.6773 m3/kg of organic dry matter (peas) to 1.1108 m3/kg of organic dry matter (mixed vegetables). All substrates had the final concentration of methane in the biogas ranged from 59.43 to 65.97%vol. The hypothesis about the impact of pre-treatment of substrates (crushing) on the quantity of the biogas produced was confirmed. The biogas production from the crushed corn kernel was significantly higher than the biogas production from substrates with a similar composition of nutrients (corn kernel, peas). Vegetables and maize waste produced during processing is a suitable substrate for anaerobic fermentation.

A comparative study was carried out using magnetic nanoparticles (MNPs) for the fabrication of non-enzymatic sensors for the continuous and rapid detection and monitoring of H2O2. Various MNPs, differing in terms of their synthesis procedure and modification, were synthesized and characterized by different techniques. The electrochemical catalytic activity of the synthesized MNPs toward the reduction in H2O2 was investigated by cyclic voltammetry. The naked MNPs showed the highest catalytic activity among all the synthesized MNPs. The biosensor based on the naked MNPs was then applied in the determination of H2O2 using chronoamperometry. The parameters such as the applied cathodic potential and the amount of MNPs on the developed biosensor were optimized. Moreover, the analytical figures of merit, including reproducibility (RSD = 6.14%), sensitivity (m = 0.0676 &micro, A &micro, M&minus, 1), limit of detection (LOD) = 27.02 &micro, mol L&minus, 1, and limit of quantification (LOQ) = 89.26 &micro, 1 of the developed biosensor indicate satisfactory analysis. Finally, MNPs were successfully utilized for the determination of H2O2 in milk.

The service tree (Sorbus domestica) is a wild fruit tree with immense medicinal and industrial value. This study aimed at determining the four major groups of antioxidants (flavonoids, phenolic acids and aldehydes, catechin and procyanidin) in rootstocks of Crataegus laevigata (genotypes O-LE-14 and O-LE-21), Aronia melanocarpa (genotypes O-LE-14 and O-LE-21), Chaenomeles japonica (genotype O-LE-9) and Cydonia oblonga (BA 29) (genotypes O-LE-14 and O-LE-21). Hyperoside (Quercetin 3-D-galactoside) was the most abundant flavonoid compound, since its average content in the rootstocks of Crataegus laevigata (O-LE-21) was 180.68 &plusmn, 0.04 &mu, g&middot, g&minus, 1. Dihydrokaempherol was the least frequently found flavonoid compound, with an average concentration of 0.43 &plusmn, 0.01 &mu, 1 in all the rootstocks of plants considered in this study. Among the phenolic compounds, the most represented one was protocatechuic acid, with 955.92 &plusmn, 10.25 &mu, 1 in the rootstocks of Aronia melanocarpa (O-LE-14). On the other hand, the least represented p-Coumaric acid exhibited the average concentration of 0.34 &plusmn, 1 in the plant rootstocks. Epicatechin was the most abundant catechin compound, with a content of 3196.37 &plusmn, 50.10 &mu, 1 in the rootstocks of Aronia melanocarpa (O-LE-14). The lowest represented catechin compound was epigallocatechin, with the average concentration of 0.95 &plusmn, 0.08 &mu, 1 in the screened plant rootstocks. From the procyanidin compounds, the most abundant one was procyanidin b2 in the rootstocks of Crataegus laevigata (O-LE-14), with a concentration of 5550.40 &plusmn, 99.56 &mu, 1. On the contrary, procyanidin a2, with an average concentration of 40.35 &plusmn, 1.61 &mu, 1, represented the least frequent procyanidin compound in all the plant rootstocks screened herein.

The presented study deals with the observation of properties of methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) in the toxic arsenic environment and influence of arsenic on antioxidant capacity. Two forms of arsenic (As(III), As(V)) with different concentrations were used for induction of the oxidative stress in tested strains. Microbiological methods showed that the growth inhibition of MSSA was higher than that of MRSA in presence of both arsenic ions. As(III) showed 24% and 33% higher anti-microbial effects than As(V) against MSSA and MRSA respectively. A similar result was found also in the experiment of reduction of biofilm-formation. By using spectrophotometry, it was revealed that As(III) induced higher antioxidant production in both bacterial cultures. Methicillin-susceptible S. aureus produced an app. 50 mg equivalent of gallic acid (GAE/1 mg of protein) and MRSA produced an app. 15 mg of GAE/1 mg of protein. The productions of metallothionein in MSSA and MRSA were decreased up to 62.41% and 55.84% respectively in presence of As ions. Reduction of As(III) and As(V) concentrations leads to a decrease in antioxidant production and increased the formation of metallothionein. All of these changes in the results were found to be significant statistically. Taken together, these experiments proved that in comparison with MSSA, MRSA is less susceptible not only to the antimicrobial effects of antibiotics but also against effects caused by metalloids, as arsenic. Thus, it can be stated that MRSA abounds with complex defensive mechanisms, which may in the future constitute significant problem in the efficiency of antibiotics alternatives as metal ions or nanoparticles.

Glucose is a typical diagnostic marker of diabetes mellitus but it may be also helpful during diagnosis of some types of poisoning, immunological disorder or long-term stress at hospitalized patients. Diagnosis of diabetes mellitus in time is indispensable for prevention of life-threatening complication and so, accurate and easy device for non-invasive and accurate self-diagnosis is necessary. Simple assay based on filter paper with chitosan layer and with immobilized enzymes glucose oxidase and peroxidase and phone camera detection has been proposed for home-care glucose detection in urine. Data were processed in RGB (red–green–blue) color model when blue color channel showed the best sensitivity to changing glucose concentrations. Assay exerted linear regression from 0 to 4 mmol/l and limit of detection was set to be 166 µmol/l. Assay was not influenced by any interfering substances including maltose, sucrose, sorbitol or fructose or by urine matrix substance such as bovine serum albumin, ascorbic acid, uric acid or urea. Measurement of glucose from spiked urine samples reveals also no influence of the matrix on the assay. Long-term stability was measured and filter papers coated by enzymes showed excellent stability for at least 9 weeks without any special treatment or package. In comparison with differently modified filter paper, filter paper with both chitosan and enzymes showed the best sensitivity to changing glucose concentration. In a conclusion, simple (phone camera detection) and fast (3-min reaction) assay for quantitative detection of glucose from urine was optimized.

The silico-carbonatite dykes of the Huanglongpu area, Lesser Qinling, China, are unusual in that they are quartzbearing, Mo-mineralised and enriched in the heavy rare earth elements (HREE) relative to typical carbonatites. The textures of REE minerals indicate crystallisation of monazite-(Ce), bastnasite-(Ce), parisite-(Ce) and aeschynite-(Ce) as magmatic phases. Burbankite was also potentially an early crystallising phase. Monazite-(Ce) was subsequently altered to produce a second generation of apatite, which was in turn replaced and overgrown by britholite-(Ce), accompanied by the formation of allanite-(Ce). Bastnasite and parisite where replaced by synchysite-(Ce) and rontgenite-(Ce). Aeschynite-(Ce) was altered to uranopyrochlore and then pyrochlore with uraninite inclusions. The mineralogical evolution re carbonatite, to more silica-rich conditions during early hydrothermal processes, to fully hydrothermal conditions accompanied by the formation of sulphateminerals. Each alteration stage resulted in the preferential leaching of the LREE and enrichment in the HREE.Mass balance considerations indicate hydrothermal HREE to themineralisation. The evolution of the in may have been the HREE source. Leaching in the presence of strong, LREE-selective ligands (Cl for the depletion in late stage minerals in the LREE, but cannot account for subsequent preferentialHREE addition. Fluid inclusion data indicate the presence of sulphate-rich brines during alteration, and hence sulphate complexationmay have been important for preferential HREE transport. AlongsideHREE-enrichedmagmatic sources, and enrichment during magmatic processes, late stage alteration with non-LREE-selective ligands may be critical in forming HREE-enriched carbonatites.flects the evolution from magmaticfluids must have contributedfluorcarbonate mineral assemblage requires an increaseaCa2+ and aCO3 2− in the metasomatic fluid (where a is activity), and breakdown of HREE-enriched calcite−) may account

Eu(III) and Tb(III) Schiff base complexes are applicable in various fields such as sensing, assays, screening protocols in vitro, and imaging studies in vitro or in vivo. Fluorescent europium and terbium complexes and their interaction with cell penetrating peptide (KKKRKC) can represent an excellent key for understanding pathway of peptide transportation though cell membrane and the application of Schiff base complexes as potential antibacterial drugs. The Schiff base–metal complexes and its conjugates with peptide were tested for their antibacterial activity against Pseudomonas aeruginosa and Salmonella typhimurium. Schiff base–metal complexes conjugated with peptide show minor toxicity in normal human PNT1A cells and high antibacterial activity against P. aeruginosa and S. typhimurium, where IC50 down to 125.9 and/or 36.1 µM were found for P. aeruginosa and S. typhimurium, respectively. Our results strongly suggest that Schiff base–metal complexes conjugated with peptide have great potential to be developed into highly effective antibacterial drug.

Mesozoic granites in the Nanling region, South China, are important primary rocks for ion-adsorption rare earth element (REE) deposits. Moreover, metallic deposits of W, Sn, Nb and Ta also develop in these granites, most of which formed in the Late Jurassic . The Qingxi and Guanxi granites in the Nanling region contain abundant REE minerals and have zircon U-Pb ages of 223.0 ± 0.7 Ma and 198.8 ± 1.4 Ma, respectively. They are of metaluminous to slightly peraluminous in character having a high K calc-alkaline composition, and have high K2O + Na2O and FeOT + MgO contents and a Ga/Al ratio similar to A-type granites. These granites plot into the post-collision field, similar to the A2-type granites. The Qingxi and Guanxi granites indicate a crust-dominant origin by having high levels of Rb and Th relative to Nb and Ta normalized to ocean-ridge granites. They are characterized by LREE enrichment and the majority of REE accumulating in the primary REE minerals include REE-phosphates and fluorocarbonates. The Guanxi rocks have a stronger negative Eu anomaly, but lower REE composition than the Qingxi granites, implying that the basement may have played an important role in the REE mineralization rather than fractional crystallization . This further implies that the basement in South China may have been subjected to different evolutionary geodynamics , resulting in different multi-metallic mineralization of W-Sn-Nb-Ta-REE hosted by large scale Mesozoic granites.

Nanobiosynthesis belongs to the most recent methods for synthesis of nanoparticles. This type of synthesis provides many advantages including the uniformity in particle shape and size. The biosynthesis has also a significant advantage regarding chemical properties of the obtained particles. In this study, we characterized the basic properties and composition of quantum dots (QDs), obtained by the extracellular biosynthesis by Escherichia coli. Furthermore, the toxicity of the biosynthesized QDs was compared to QDs prepared by microwave synthesis. The obtained results revealed the presence of cyan CdTe QDs after removal of substantial amounts of organic compounds, which stabilized the nanoparticle surface. QDs toxicity was evaluated using three cell lines Human Foreskin Fibroblast (HFF), Human Prostate Cancer cells (PC-3) and Breast Cancer cells (MCF-7) and the MTT assay. The test revealed differences in the toxicity between variants of QDs, varying about 10% in the HFF and 30% in the MCF-7 cell lines. The toxicity of the biosynthesized QDs to the PC-3 cell lines was about 35% lower in comparison with the QDs prepared by microwave synthesis.

The Lugiin Gol nepheline syenite intrusion, Mongolia, hosts a range of carbonatite dikes mineralized in rare-earth elements (REE). Both carbonatites and nepheline syenite-fluorite-calcite veinlets are host to a previously unreported macroscale texture involving pseudo-graphic intergrowths of fluorite and calcite. The inclusions within calcite occur as either pure fluorite, with associated REE minerals within the surrounding calcite, or as mixed calcite-fluorite inclusions, with associated zirconosilicate minerals. Consideration of the nature of the texture, and the proportions of fluorite and calcite present (∼29 and 71 mol%, respectively), indicates that these textures most likely formed either through the immiscible separation of carbonate and fluoride melts, or from cotectic crystallization of a carbonate-fluoride melt. Laser ablation ICP-MS analyses show the pure fluorite inclusions to be depleted in REE relative to the calcite. A model is proposed, in which a carbonate-fluoride melt phase enriched in Zr and the REE, separated from a phonolitic melt, and then either unmixed or underwent cotectic crystallization to generate an REE-rich carbonate melt and an REE-poor fluoride phase. The separation of the fluoride phase (either solid or melt) may have contributed to the enrichment of the carbonate melt in REE, and ultimately its saturation with REE minerals. Previous data have suggested that carbonate melts separated from silicate melts are relatively depleted in the REE, and thus melt immiscibility cannot result in the formation of REE-enriched carbonatites. The observations presented here provide a mechanism by which this could occur, as under either model the textures imply initial separation of a mixed carbonate-fluoride melt from a silicate magma. The separation of an REE-enriched carbonate-fluoride melt from phonolitic magma is a hitherto unrecognized mechanism for REE-enrichment in carbonatites, and may play an important role in the formation of shallow magmatic REE deposits. Keywords: Silicate-carbonate-fluoride melt immiscibility, Carbonatite, Alkaline syenite, Shallow REE deposit, Lugiin Gol, Mongolia

MS, AF and FW acknowledge the support of the NERC SoS:RARE consortium grant (NE/M011267/1). D. Kavecsanszki acknowledges the support of a postgraduate fellowship from the College of Engineering, Mathematics and Physical Sciences at the University of Exeter. The rare earth elements are unusual when defining giant-sized ore deposits, as resources are often quoted as total rare earth oxide, but the importance of a deposit may be related to the grade for individual, or a limited group of, the elements. Taking the total REE resource, only one currently known deposit (Bayan Obo) would class as giant (>1.7×107 tonnes contained metal), but a range of others classify as large (>1.7×106 tonnes). With the exception of unclassified resource estimates from the Olympic Dam IOCG deposit, all of these deposits are related to alkaline igneous activity – either carbonatites or agpaitic nepheline syenites. The total resource in these deposits must relate to the scale of the primary igneous source, but the grade is a complex function of igneous source, magmatic crystallisation, hydrothermal modification and supergene enrichment during weathering. Isotopic data suggest that the sources conducive to the formation of large REE deposits are developed in subcontinental lithospheric mantle, enriched in trace elements either by plume activity, or by previous subduction. The reactivation of such enriched mantle domains in relatively restricted geographical areas may have played a role in the formation of some of the largest deposits (e.g. Bayan Obo). Hydrothermal activity involving fluids from magmatic to meteoric sources may result in the redistribution of the REE and increases in grade, depending on primary mineralogy and the availability of ligands. Weathering and supergene enrichment of carbonatite has played a role in the formation of the highest grade deposits at Mount Weld (Australia) and Tomtor (Russia). For the individual REE with the current highest economic value (Nd and the HREE), the boundaries for the large and giant size classes are 2 orders of magnitude lower, and deposits enriched in these metals (agpaitic systems, ion absorption deposits) may have significant economic impact in the near future. Publisher PDF

The effects of ultrasonic milling, dry and wet ball milling, and vibro-milling on the particulate properties, crystalline characteristics, morphology, and surface area of clinoptilolite (Cpt) have been investigated. Laser beam scattering technique, X-ray diffraction (XRD), scanning electron microscopy (SEM), and nitrogen adsorption/desorption at 77 K are used to characterize the initial and ground Cpt powders. Results show that Cpt particle size is significantly reduced by all carried out milling methods in which vibro-milling could produce particles with diameter less than 100 nm. The size distribution of Cpt is remarkably narrowed by using vibro- and wet ball milling. The crystallinity of Cpt noticeably decreases for the samples obtained by ball milling while vibro- and ultrasonic millings show a negligible effect on crystallinity. The specific surface area of Cpt is enhanced by all four milling methods.

Carbonatites are abundant in the rare earth elements (REE), and they host the most important REE resources in the world. However, the mechanisms that concentrate these elements during carbonatitic magmatic processes are still poorly constrained. Here, we report the occurrence of apatite-hosted melt inclusions from the Ulgii Khiid carbonatites, Mongolia, and use these to reconstruct the evolution of REE concentrations and patterns in early, primary carbonatite magma. The melt inclusions consist of a varied polycrystalline assemblage of daughter minerals, including calcite, diopside, phlogopite, magnetite, pyrite, monazite, parisite, and a phosphate glass which is remarkably enriched in REE. Heating-quenching experiments show that the homogenization temperatures of the inclusions are above 1200 °C and produce three immiscible liquid phases (i.e., phosphate-, silicate-, and Fe-silicate-melt). The phosphate melt has much higher REE content than the silicate melts. We, therefore, suggest that the melt inclusions trapped a REE-, P- and silicate-enriched carbonate melt produced via carbonate-silicate liquid immiscibility. During this process, both REE and P preferentially incorporated into the carbonate melt. With subsequent crystal fractionation of REE- and P-poor carbonate and silicate minerals, the separated carbonatitic melt becomes P-REE-saturated, forming REE minerals and an immiscible REE-rich phosphate melt. The phosphate melt is highly efficient at concentrating REE during the immiscibility process and plays a crucial role in controlling the REE budget in the P-rich carbonatite magmas.

The South Qinling orogen in central China hosts carbonatites occurring as stocks associated with syenites and collectively regarded as the Miaoya intrusive complex. The complex hosts economic resources of rare-earth elements (REE) and Nb. The Miaoya syenites are strongly metasomatized at the contact with the carbonatites and cross-cut by carbonate and felsic veinlets. Small oscillatory-zoned crystals of zircons from the syenites give a concordant U–Pb age of 147 ± 0.5 Ma, which differs significantly from the ages of both large magmatic zircon grains from the syenites and primary monazite from the carbonatites (766 Ma and 234 Ma, respectively). To account for the possibility that the Miaoya syenites are coeval and cogenetic with the carbonatites, the trace-element budget of both rock types was examined in detail. The Miaoya carbonatite contains primary REE-rich fluorapatite and monazite, which precipitated earlier than the rock-forming REE-poor calcite, indicating that the primary carbonatitic magma was rich in REE. The compositions of the parental syenitic and carbonatitic magmas, calculated on the basis of the trace-element composition of primary fluorapatite in the two rock suites, show that the carbonatitic magma contained higher Sr and REE (La–Tb), but lower Ba, Pb, Th, U, Nb and Ta levels in comparison with the syenitic melt. These differences are inconsistent with derivation of the Miaoya rocks from a homogeneous carbonate–silicate melt by immiscibility or crystal fractionation. It is therefore concluded that the carbonatitic magma at Miaoya was generated directly in the mantle. Emplacement of the carbonatites in the South Qinling orogen marked transition to a postorogenic regime, and was preceded by oceanic crust subduction and closure of the Mianlue Ocean in the Triassic. Our models show that melting of the Mianlue crust and up to 10 wt.% of sediments cannot produce the levels of REE enrichment observed in the Miaoya carbonatites. More complex models, involving recycling of the Mianlue oceanic crust and a REE-rich carbonate liquid from an old deep-seated mantle source are required to explain the observed trace-element characteristics of the Miaoya carbonatites.

The sources and formation conditions of unconventional Zr–Nb–REE mineralisation (REE = rare earth elements) presently found in increasing number worldwide are still poorly constrained. One particular problem is the specific role of magmatic and hydrothermal processes active in various geological settings. Investigation of Zr–Nb–REE mineralisation at Khalzan Buregte and Tsakhir, Western Mongolia, enables to evaluate magmatic processes preceding economic mineralisation and, in a second step, to compare similar ore-forming processes developing in host rocks of contrasting rock composition (low- vs. high-silica rocks). The genesis of the Zr–Nb–REE mineralisation is re-assessed using field observations, whole rock analysis (chemical composition, quantitative modal analysis by X-ray diffraction) and by the application of various transmitted light and electron microscopic techniques. Coarse-grained intrusive bodies, dikes and volcanic rocks of alkaline, silica-saturated composition were found to be contemporarily emplaced at subvolcanic to volcanic levels forming four alkaline massifs within the Khalzan Buregte area. The whole rock composition of weakly altered magmatic rocks ranges from syenite to quartz monzonite and alkaline granite (alkali feldspar syenite to alkali feldspar granite according to their modal composition). Magmatic and at least two subsequent hydrothermal processes contributed significantly to the formation of economic concentrations of high field strength elements (HFSE) such as Zr, Hf, Nb, Ta, REE and Y in the Khalzan Buregte deposit and in the nearby Tsakhir prospect. Mixing of magma from at least three sources and the formation of potassium feldspar cumulates resulted in local enrichment of Zr, Nb and light rare earth elements (LREE) in the rocks up to sub-economic levels. There was no significant increase in Y and heavy rare earth elements (HREE) during magmatism. Multistage metasomatic alteration resulted in a pronounced chemical and mineralogical heterogeneity of associated alteration assemblages. The main hosts of Zr and Hf in the ores are zircon and other zirconium silicates (gittinsite, catapleiite-(Ca) and elpidite). The rare metals Nb and Ta are mainly contained in various types of pyrochlore (Khalzan Buregte) and, to a lesser extent, in fergusonite and other minerals (Tsakhir). A large variety of REE- and Y-bearing minerals have been identified, including oxides, fluorocarbonates and silicates. Early hydrothermal alteration by silica- and carbonate-rich fluids yielded extreme concentrations of Zr, Nb and LREE. Later alteration resulted in enrichment of Y and HREE. In the latter case, fluids were very rich in fluorine. Our preliminary genetic model assumes a carbonatite-related fluid system responsible for the early alteration that occurred late during or postdating the intrusion/extrusion of the silica-saturated magmas. A “Li-F granite-type” fluid system was active during the late alteration. The interplay of all these processes resulted in the formation of a complex, economic Zr–Nb–REE mineralisation at Khalzan Buregte.

Modification of carbon materials, especially graphene-based materials, has wide applications in electrochemical detection such as electrochemical lab-on-chip devices. A glassy carbon electrode (GCE) modified with chemically alternated graphene oxide was used as a working electrode (glassy carbon modified by graphene oxide with sulphur containing compounds and Nafion) for detection of nucleobases in hydrolysed samples (HCl pH = 2.9, 100 °C, 1 h, neutralization by NaOH). It was found out that modification, especially with trithiocyanuric acid, increased the sensitivity of detection in comparison with pure GCE. All processes were finally implemented in a microfluidic chip formed with a 3D printer by fused deposition modelling technology. As a material for chip fabrication, acrylonitrile butadiene styrene was chosen because of its mechanical and chemical stability. The chip contained the one chamber for the hydrolysis of the nucleic acid and another for the electrochemical detection by the modified GCE. This chamber was fabricated to allow for replacement of the GCE.

The Huanglongpu carbonatite-related Mo ore field is located in the Lesser Qinling Orogenic belt in the southern margin of the North China block. The ore field is composed of six deposits, Yuantou, Wengongling, Dashigou, Shijiawan, Taoyuan and Erdaohe, all of which are genetically related to carbonatite dykes except for the Shijiawan deposit which is associated with a granitic porphyry. The Yuantou carbonatite dykes intruded into Archean gneiss and other carbonatites emplaced into Mesoproterozoic volcanic and sediment rocks. The carbonatites are mainly composed of calcite and variable amounts of quartz and K-feldspar and minor molybdenite. Re–Os dating of molybdenite from the Yuantou carbonatite yields a weighted average age of 225.0 ± 7.6 Ma, consistent with the molybdenite age (221 Ma) from the Dashigou deposit. The rocks are characterized by high heavy REE (HREE) contents and consistent flat REE distribution patterns with La/Ybcn ~ 1. Quartz in the carbonatites from Yuantou and Dashigou deposits shows consistent O isotopes (8.1–10.2‰) similar to the associated calcite (7.2–9.5‰). The quartz and associated K-feldspar contain lower Zr, Hf and higher HREE abundances and negligible Eu anomaly relative to those from the granite porphyry in Shijiawan. Both minerals are primary products in the carbonatitic liquid, and not captured from the wall-rocks or crustal-derived silicate magmas, or a hydrothermal origin. Thus, the Huanglongpu carbonatitic liquids were enriched in Si and Mo, which may be produced by intensely fractional crystallization of non-silicate minerals.

Mineralization with ion adsorption rare earth elements (REEs) in the weathering profile of granitoid rocks from Nanling region of Southeast China is an important REE resource, especially for heavy REE (HREE) and Y. However, the Jurassic granites in Zhaibei which host the ion adsorption light REE (LREE) ores are rare. It is of peraluminous and high K calc-alkaline composition, which has similar geochemical features of high K2O + Na2O and Zr + Nb + Ce + Y contents and Ga/Al ratio to A-type granite. Based on the chemical discrimination criteria of Eby [Geology 20 (1992) 641], the Zhaibei granite belongs to A1-type and has similar source to ocean island basalts. The rock is enriched in LREE and contains abundant REE minerals including LREE-phosphates and halides. Minor LREE was also determined in the feldspar and biotite, which shows negligible and negative Eu anomalies, respectively. This indicates that the Zhaibei granite was generated by extreme differentiation of basaltic parent magmas. In contrast, granites associated with ion adsorption HREE ores contain amounts of HREE minerals, and show similar geochemical characteristics with fractionated felsic granites. Note that most Jurassic granitoids in the Nanling region contain no REE minerals and cannot produce REE mineralization. They belong to unfractionated M-, I- and S-type granites. Therefore, accumulation of REE in the weathering profile is controlled by primary REE mineral compositions in the granitoids. Intense fractional crystallization plays a role on REE enrichment in the Nanling granitoid rocks.

Oxidative stress is a pathological process related to not only animal kingdom but also plants. Regarding oxidative stress in plants, heavy metals are frequently discussed as causative stimuli with relevance to ecology. Because heavy metals have broad technological importance, they can easily contaminate the environment. Much of previous effort regarding the harmful impact of the heavy metals was given to their toxicology in the animals and humans. Their implication in plant pathogeneses is less known and remains underestimated.The current paper summarizes basic facts about heavy metals, their distribution in soil, mobility, accumulation by plants, and initiation of oxidative stress including the decline in basal metabolism. The both actual and frontier studies in the field are summarized and discussed. The major pathophysiological pathways are introduced as well and link between heavy metals toxicity and their ability to initiate an oxidative damage is provided. Mobility and bioaccessibility of the metals is also considered as key factors in their impact on oxidative stress development in the plant. The metals like lead, mercury, copper, cadmium, iron, zinc, nickel, vanadium are depicted in the text.Heavy metals appear to be significant contributors to pathological processes in the plants and oxidative stress is probably an important contributor to the effect. The most sensitive plant species are enlisted and discussed in this review. The facts presented here outline next effort to investigate pathological processes in the plants.

This study shows the effects of spices, and their phenolic and flavonoid compounds, on prostate cell lines (PNT1A, 22RV1 and PC3). The results of an MTT assay on extracts from eight spices revealed the strongest inhibitory effects were from black pepper and caraway seed extracts. The strongest inhibitory effect on prostatic cells was observed after the application of extracts of spices in concentration of 12.5 mg.mL- 1. An LC/MS analysis identified that the most abundant phenolic and flavonoid compounds in black pepper are 3,4-dihydroxybenzaldehyde and naringenin chalcone, while the most abundant phenolic and flavonoid compounds in caraway seeds are neochlorogenic acid and apigenin. Using an MTT assay for the phenolic and flavonoid compounds from spices, we identified the IC50 value of ~1 mmol.L- 1 PNT1A. The scratch test demonstrated that the most potent inhibitory effect on PNT1A, 22RV1 and PC3 cells is from the naringenin chalcone contained in black pepper. From the spectrum of compounds assessed, the naringenin chalcone contained in black pepper was identified as the most potent inhibitor of the growth of prostate cells. info:eu-repo/semantics/openAccess

The main mechanism of action of platinum-based cytostatic drugs – cisplatin, oxaliplatin and carboplatin – is the formation of DNA cross-links, which restricts the transcription due to the disability of DNA to enter the active site of the polymerase. The polymerase chain reaction (PCR) was employed as a simplified model of the amplification process in the cell nucleus. PCR with fluorescently labelled dideoxynucleotides commonly employed for DNA sequencing was used to monitor the effect of platinum-based cytostatics on DNA in terms of decrease in labeling efficiency dependent on a presence of the DNA-drug cross-link. It was found that significantly different amounts of the drugs - cisplatin (0.21 μg/mL), oxaliplatin (5.23 μg/mL), and carboplatin (71.11 μg/mL) - were required to cause the same quenching effect (50%) on the fluorescent labelling of 50 μg/mL of DNA. Moreover, it was found that even though the amounts of the drugs was applied to the reaction mixture differing by several orders of magnitude, the amount of incorporated platinum, quantified by inductively coupled plasma mass spectrometry, was in all cases at the level of tenths of μg per 5 μg of DNA.

Sulfur mustard, in a chemical name bis(2-chloroethyl) sulfide, is a chemical warfare agent. It is cytotoxic and blister forming once spread over the skin. Though exact molecular mechanism of sulfur mustard toxic action remains unknown, inflammation and oxidative stress development are considered as the most relevant pathological consequences. Applications of either low-molecular weight antioxidants or cofactors for enzymatic antioxidants are considered as suitable ways how to ameliorate the poisoning. In this article, survey of literature on countermeasures against sulfur mustard poisoning are given and evidence of oxidative stress role during sulfur mustard poisoning and availability of antioxidants for the therapy are discussed.

Oxidative stress is a pathological process related to not only animal kingdom but also plants. Regarding oxidative stress in plants, heavy metals are frequently discussed as causative stimuli with relevance to ecology. Because heavy metals have broad technological importance, they can easily contaminate the environment. Much of previous effort regarding the harmful impact of the heavy metals was given to their toxicology in the animals and humans. Their implication in plant pathogeneses is less known and remains underestimated.