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The authors here analyse the petrology of the meteorite NWA 8321 (parent body Vesta). They find sulfidation processes of olivine suggesting metasomatism in the Vestan interior and a partial melting origin for the host noritic diogenite.

The Cathaysia Block is located in southeastern part of South China, which situates in the west Pacific subduction zone. It is thought to have undergone a compression-extension transition of the continental crust during Mesozoic-Cenozoic during the subduction of Pacific Plate beneath Eurasia-Pacific Plate, resulting in extensive magmatism, extensional basins and reactivation of fault systems. Although some mechanisms such as the trench roll-back have been generally proposed for the compression-extension transition, the timing and progress of the transition under a convergence setting remain ambiguous due to lack of suitable geological records and overprinting by later tectonic events. In this study, a numerical thermo-dynamical program was employed to evaluate how variable slab angles, thermal gradients of the lithospheres and convergence velocities would give rise to the change of crustal stress in a convergent subduction zone. Model results show that higher slab dip angle, lower convergence velocity and higher lithospheric thermal gradient facilitate the subduction process. The modeling results reveal the continental crust stress is dominated by horizontal compression during the early stage of the subduction, which could revert to a horizontal extension in the back-arc region, combing with the roll-back of the subducting slab and development of mantle upwelling. The parameters facilitating the subduction process also favor the compression-extension transition in the upper plate of the subduction zone. Such results corroborate the geology of the Cathaysia Block: the initiation of the extensional regime in the Cathaysia Block occurring was probably triggered by roll-back of the slowly subducting slab.

Resin adsorbent for gold recovery have the characteristics of simple preparation, good reusability and low consumption performance, but their shortcomings of low adsorption efficiency and poor adsorption capacity cannot be ignored. Based on this, a novel adsorbent with high adsorption performance towards Au(III) was prepared by functionalizing D301 resin with 1-vinylimidazole using the surface-initiated graft-polymerization method. The physicochemical characteristics of D301-g-PVIM (PVIM -- polyvinylimidazole) were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, Brunauer--Emmett--Teller and elemental analysis. The adsorption capacity of Au(III) was studied by a static adsorption experiment. The maximum adsorption capacity of D301-g-PVIM for Au(III) was 543.9 mg g--1. The kinetic study shows that the adsorption data can well described by the pseudo-second-order kinetic model. The equilibrium isotherm for the adsorption of Au(III) on D301-g-PVIM has a good correlation with the Freundlich model, and the adsorption is a multilayer sorption. The adsorption thermodynamics study indicated that the adsorption process is spontaneously endothermic. Repeated use experiments showed that D301-g-PVIM has high efficiency and good regeneration performance. [ABSTRACT FROM AUTHOR]

It is of great significance to effectively remove impurity such as Fe from rare earth elements because the trace of Fe(III) have serious damage to the performance of rare earth materials. In this study, a hair-based activated carbon (ACH*) was synthesized and characterized by surface area analyzer, Fourier transform infrared spectroscopy and elemental analysis. The identification and removal of the performance of ACH600 for Fe(III) in the La(III) solution was studied. The adsorption capacity of ACH600 for Fe(III) was 15.54 mg/g and the removal rate reached up to 98.6% by virtue of abundant nitrogen-containing functional group. The selectivity coefficient of ACH600 for Fe(III) was 8.3 relative to La(III). In addition, the ACH600 also has good regeneration and reusability. [ABSTRACT FROM AUTHOR]

In this study, two novel adsorbents (TSCD301 and TCHD301) were successfully synthesized through ring-opening reaction between the amino of thiosemicarbazide or thiocarbohydrazide and the epoxy group of poly(glycidyl methacrylate). The adsorption performance and recognition selectivity of TCHD301 and TSCD301 toward AuCl4- were studied by batch adsorption experiments. The results showed that the equilibrium adsorption capacity of TSCD301 and TCHD301 toward AuCl4- could reach 410.76 and 566.59 mg·g-1 at 298 K and pH of 2, respectively. The adsorption process could be described using the pseudo-second-order model, and the adsorption behavior of AuCl4- on TSCD301 and TCHD301 was typical monolayer adsorption. In mixed solution, two adsorbents had excellent selectivity toward AuCl4-. In addition, the adsorption capacity of adsorbent did not change significantly in repeated adsorption-desorption experiment. [ABSTRACT FROM AUTHOR]

In this study, urea-modified D301 resin, UD301, was obtained successfully. The surface properties, chemical functional groups, element content, and surface morphology were investigated. The adsorption properties of UD301 for toxic heavy metal ions (Pb(II), Hg(II), Cd(II), and Ni(II)) were studied by batch method and the practical application value was evaluated by column method. The experimental results showed that UD301 possesses strong adsorption ability for Pb(II), Hg(II), Cd(II), and Ni(II). pH and temperature has a great influence on the adsorption capacity in the studied range. The adsorption capacities of UD301 towards Pb(II), Hg(II), Cd(II), and Ni(II) could reach 412.8, 396.9, 210.2, and 121.9 mg·g-1 at 293 K and pH of 6, respectively. The adsorption process was a typical monolayer chemical adsorption and could be well described by the Lagergren-first-order model. The adsorption was also an endothermic and spontaneous process drived by entropy. In addition, UD301 could be reused almost without any loss in the adsorption capacity. [ABSTRACT FROM AUTHOR]

While a high osmolarity medium activates Cpx signaling and causes CpxR to repress csgD expression, and efflux protein TolC protein plays an important role in biofilm formation in Escherichia coli, whether TolC also responds to an osmolarity change to regulate biofilm formation in extraintestinal pathogenic E. coli (ExPEC) remains unknown. In this study, we constructed ΔtolC mutant and complement ExPEC strains to investigate the role of TolC in the retention of biofilm formation and curli production capability under different osmotic conditions. The ΔtolC mutant showed significantly decreased biofilm formation and lost the ability to produce curli fimbriae compared to its parent ExPEC strain PPECC42 when cultured in M9 medium or 1/2 M9 medium of increased osmolarity with NaCl or sucrose at 28°C. However, biofilm formation and curli production levels were restored to wild-type levels in the ΔtolC mutant in 1/2M9medium. We propose for the first time that TolC protein is able to formbiofilm even under high osmotic stress. Our findings reveal an interplay between the role of TolC in ExPEC biofilm formation and the osmolarity of the surrounding environment, thus providing guidance for the development of a treatment for ExPEC biofilm formation. [ABSTRACT FROM AUTHOR]

The eastern Tianshan orogenic belt, northwestern China, hosts ~120 mafic-ultramafic intrusions and at least six of them host significant Ni-Cu sulfide mineralization of which the Permian Huangshandong intrusion is the largest. The mafic-ultramafic rocks of the Huangshandong intrusion comprise lherzolite, gabbronorite, gabbro, and diorite. Individual orebodies are composed of pyrrhotite, pentlandite, and chalcopyrite as disseminated to net-textured or massive to semimassive sulfide mineralization. Oxide-bearing sulfide mineralization contains 1 to 5% magmatic magnetite that has ilmenite and spinel exsolution lamellae. Silicate rocks and sulfide mineralization have variable whole-rock platinum group elements (PGE; 0.38-362 ppb), Cu (42-97,000 ppm), and Ni (26-33,000 ppm) concentrations. The mineralization is broken out into two types termed oxide rich and oxide poor. The oxide-rich sulfide mineralization has high PGE concentrations with low 187Re/188Os ratios (38.9-151), whereas oxide-poor sulfide mineralization has low PGE concentrations with high 187Re/188Os (159-781). Both oxide-rich and -poor sulfide mineralization have highly variable γOs values (49-189 and 30-278, respectively). Oxide-rich sulfide mineralization contains magnetite with variable amounts of MgO, TiO2, Al2O3, FeOtotal, Cr, V, Zn, and Sn, indicating that they crystallized from different stages during magma differentiation. We propose that the host intrusion and associated sulfide mineralization were derived from high Mg basaltic magmas from a mantle source that was previously modified by subducted oceanic slab. Oxide-poor sulfide mineralization of the Huangshandong intrusion formed from a magma that underwent <0.03% sulfide removal before emplacement and was thus PGE depleted. Oxide-rich sulfide mineralization formed from magma that had much lower amounts of sulfide (<0.003%) removed in the early stage before entering the Huangshandong magma chamber. An early sulfide saturation event was likely associated with fractionation of silicate minerals in a deep-staging magma chamber. The second sulfide saturation event that formed the sulfide mineralization was probably triggered by selective crustal contamination and fractionation in the high-level chamber where mixing of magmas and accumulation of immiscible sulfide occurred. [ABSTRACT FROM AUTHOR]

The Kalatongke Cu-Ni sulfide deposit in the Paleozoic Altay orogenic belt, NW China, is hosted in a Permian mafic intrusion consisting of norite, troctolite, gabbro, and diorite. Disseminated Ni-Cu, massive Ni-Cu, and massive Cu-rich sulfide ores are mainly hosted in norite and gabbro. Some massive Ni-Cu ores also occur in the Carboniferous sedimentary rocks. The geologic and compositional relationships between various sulfide ores and the rocks of Kalatongke offer a new interpretation of the sequence of emplacement of the magmas, which underpins an understanding of die compositions of the ores and the formation of the Kalatongke deposit. Olivine grains from disseminated Ni-Cu ores have Fo values ranging from 71.6 to 78.0 mol 98 and Ni contents from 1.000 to 2,200 ppm. Typically, Ni decreases from the cores to the rims from 2.000 to 1,000 ppm at constant Fo content, indicating the reaction of early-formed olivine with later-segregated sulfide melt. Cr spinels at Kalatongke are highly enriched in Fe3+ and Fe2+, with relatively low Cr, Al, and Ti, reflecting reaction with evoked trapped intercumulus melt. Norites are depleted in Nb, Ta, Zr, Hf, and Th and enriched in Sr and Ba, whereas disseminated Ni-Cu sulfide ores have considerable depletion of Kb and enrichment of Sr and Ba and lack depletion of Nb, Ta, Zr, and Hf, indicating their different origins. Disseminated Ni-Cu sulfide ores have bulk compositions with variable Cu and Ni contents which are much lower than those of massive Cu-rich and Ni-Cu ores, but disseminated and massive Ni-Cu ores have similar PCE contents with relatively low Pd/Ir ratios. Massive Cu-rich ores have much higher Pd and Pt with very high Pd/Ir ratios. The Kalatongke Cu-Ni sulfide deposit appears to have formed from two different pulses of PGE-poor and Cu-rich basaltic magmas that underwent different degrees of assimilation and fractional crystallization. The first magma pulse gained sulfide saturation because of minor crystal contamination and fractionated a small amount of sulfide (<0.03%); the evolved melt then intruded and assimilated crystal materials to attain sulfide saturation again. Sulfide liquid segregated from the magma to form the massive sulfide melts and residual magma formed the noritic rocks in the shallow magma chamber. The segregated massive sulfide melts then underwent further fractionation to form massive Ni-Cu and massive Cu-rich ores. The second pulse of magma after removal of sulfides (<0.02%) experienced more crystal contamination and re attained S saturation. This new S-saturated and phenocryst-laden magma intruded the earlier formed massive sulfide ores and norites and formed the disseminated sulfide ores. [ABSTRACT FROM AUTHOR]

Histamine (HA), a biogenic amine with a broad spectrum of activities in both physiological and pathological settings, plays a key regulatory role in experimental allergic encephalomyelitis, the autoimmune model of multiple sclerosis. HA exerts its effect through four G protein-coupled receptors designated HA receptor H1, H2, H3, and H4. We report here that, compared with wild-type animals, mice with a disrupted HA H3 receptor (H3RKO), the expression of which is normally confined to cells of the nervous system, develop more severe disease and neuroinflammation. We show that this effect is associated with dysregulation of blood-brain barrier permeability and increased expression of MIP-2, IP-10, and CXCR3 by peripheral T cells. Our data suggest that pharmacological targeting of the H3R may be useful in preventing the development and formation of new lesions in multiple sclerosis, thereby significantly limiting the progression of the disease. [ABSTRACT FROM AUTHOR]

The magmatic processes beneath the active continental margins are very complicated and affect structures and compositions of the arc roots. Neoproterozoic igneous rocks are widely distributed around the margins of the Tarim Block in NW China. The Xingdier mafic-ultramafic intrusion is a composite body, located at the northern margin of the Tarim Block, and consists of gabbro, pyroxenite, and peridotite units. The gabbro unit has a secondary ion mass spectrometry zircon U-Pb age of 727 ± 5 Ma. Rocks from the Xingdier intrusion have a large range of MgO (12.9--32.8 wt%) and SiO2 (43.0-57.9 wt%), and low K2O + Na2O (0.11-2.25 wt%) contents. They have right inclined chondrite-normalized rare earth element patterns with (La/Yb)N ratios of 2.2-8.6. Their primitive mantle normalized trace element patterns show arc-affinity geochemical features characterized by enrichment in Rb, Ba, Th, U, and Pb and depletion in Nb, Ta, and Ti. They have variable initial 87Sr/86Sr ratios (0.7063-0.7093), εNd(t) values (-2.9 to -7.8), 206Pb/204Pb (17.08-17.80), 207Pb/204Pb (15.42-15.49), and 208Pb/204Pb ratios (37.48-38.05), forming an evolution trend from the peridotite unit to the gabbro and pyroxenite units. Clinopyroxene in the three units is chemically similar to those formed in hydrous magmas. The spinel inclusions in olivine from the peridotite unit show unmixing texture and have high Al contents and oxygen fugacity of ~FMQ+1. Therefore, the parental magma was probably derived from a lithospheric mantle enriched by slab-derived fluids. Rocks from the gabbro and peridotite units are proposed to have been derived from olivine-normative melts, whereas rocks from the pyroxenite unit are cumulates from the quartz-normative melts. Such contrasting parental magmas resulted from variable degrees of crustal contamination and fractional crystallization in the arc root. [ABSTRACT FROM AUTHOR]

The Altai orogen is an important constituent of the Central Asian Orogenic Belt (CAOB). The main orogenic processes occurred mainly in the early to middle Paleozoic and involved a series of northward subduction and terrane accretion. However, termination of the accretionary and post-accretionary processes remains poorly defined. The Chinese Altai is located in the southern part of this orogeny, which is widely intruded by Permian granitic plutons. These plutons are approximately circular in shape, free of deformation and generally cutting pre-Permian structures, suggesting a post-tectonic formation. We report the results of geochronological and geochemical data from five specific granitic plutons (Buerjin, Xibodu, Daqiaonan, Aweitan, and Adenbluk), which all yielded magmatic zircon U-Pb ages of about 270 Ma. These plutons are composed of high-K calc-alkaline rocks, including K-feldspar megaphyric granite, biotite granite and monzogranite that have metaluminous to weakly LREE-enriched, coupled with negative Eu anomalies. Significant negative anomalies of Ba, Sr, P, and Ti are also observed in the primitive-mantle normalized diagram. They have positive whole-rock εNd(t) (+1.3 to +7.2) and zircon εHf(t) values (+5.6 to +12.9), yielding Sm-Nd model ages of ⩽0.9 Ga. Therefore, these granitoids are proposed to have been generated by differentiation of mantle-derived magmas with variable crustal contamination. In view of the field occurrence, structural analysis, regional tectonics and geochemical characteristics, these Permian plutons are concluded to be post-accretionary or post-collisional. Asthenospheric upwelling after the collision and amalgamation of the Altai and Junggar blocks could have caused the mantle-derived magmas that evolved to form the granitoids. We note diat Permian intrusions are not only widespread but also voluminous in the CAOB. They mostly are post-collisional products, and some of them might have been related to the large igneous province activity in the Tarim Block. [ABSTRACT FROM AUTHOR]

The current study aimed to establish simple and quick quality evaluation method of Chishao based on QAMS. Oxypaeoniflorin is used as a marker in the Chishao root. Based on it, the content of other components could be obtained by establishing the mathematical relationship. UPLC method was used to collect data, and the detection wavelengths were 230nm (benzoic acid, paeoniflorin), 263nm (hydroxy paeoniflorin) 274nm (gallic acid, paeoniflorin, catechin), respectively. The stationary phase was an Agilent ZORBAX SB-C 18 and the mobile phase was acetonitrile -0.1% formic acid-water. The gradient elution method was adopted at the certain flow rate (0.3 mL/min). The column temperature set 40 o C, and the injection volume was 1μL. Multiple reaction monitoring mode was selected for data collection. The linear ranges of benzoic acid, paeoniflorin, hydroxy-paeoniflorin, gallic acid, catechin and paeoniflorinhad good linearity (r ≥0.9995). The UPLC method was established to determine the content of paeoniflorin, benzoic acid, catechin, gallic acid, paeoniflorin, andhydroxy-paeoniflorin in Radix Paeoniae Rubra. In the current study, the method for the chemical components in Radix Paeoniae Rubra to provide the evaluation basis of medicinal effects.