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The Qinling orogen records the prolonged amalgamation history between the North China Block (NCB) and the South China Block (SCB) accompanied by major granitoid intrusions during the Triassic. However, the petrogenesis of these granitoids, especially that of the peraluminous granites, remains a matter of debate. Detailed study of these peraluminous granites, which are the products of crustal melting, will give insights into the melting process and petrogenesis of peraluminous magmas and will further constrain the regional geological evolution. In this study, Xiahe (XH) tourmaline-bearing two-mica granite and Baijiazhuang (BJZ) two-mica granite were selected for systematic analysis of their mineralogy, petrology, zircon U-Pb geochronology, and geochemistry. The zircon U-Pb dating showed that the XH and BJZ granites were emplaced at approximately 242 Ma and approximately 214 Ma, respectively. The presence of muscovite and tourmaline, high peraluminosity at >1.1, low oxygen fugacity (ƒO2) conditions below the fayalite–magnetite–quartz (FMQ) buffer, and low zircon saturation temperatures indicate sedimentary protolith (S-type) granitic affinity. The low CaO/Na2O ratios

High Mg diorites provide important insights into crust-mantle interaction during tectonic evolution of orogenic belt. An integrated study including zircon U-Pb dating, whole-rock geochemistry and isotopic compositions of Sr and Nd was carried out on high Mg diorites of the Wulong pluton located in the narrowest part of the South Qinling Belt. Crystallized ages of 218-210 Ma are obtained in combination with the published data. These rocks are characterized with relatively high MgO (2.76–7.17%), Cr (68.7-310 ppm) and Ni (21.3–76.3 ppm) contents. Most diorites exhibit high Sr/Y and La/Yb ratios with negligible Eu anomaly. Isotopic compositions of whole-rock show enriched attributes (87Sr/86Sr(i) = 0.7050–0.7071, eNd(t) = −7.56 to −3.45). Geochemical models indicate that these rocks did not result from melting of subducted slab, magma mixing, fractional crystallization or melts derived from delaminated lower crust reacted with mantle. Instead, high Mg diorites were generated through basaltic melts derived from asthenosphere mantle assimilating crustal components with crystallized phase of garnet-bearing amphibolite (AFC). Together with regional geological setting of the South Qinling Belt, we propose that the parental magma of these high Mg diorites was probably originated from upwelled asthenosphere mantle at the base of thinned crust after delamination of thickened crust during Late Triassic. The continental crust of the South Qinling Belt was thickened as a result of collision with the Yangtze Block during Middle Triassic. Then eclogitized lower crust collapsed and foundered into asthenosphere mantle due to partial melting of thickened crust during Late Triassic. In response, the upwelling and underplating of asthenosphere mantle took place at the base of continental crust. Moreover, upwelling of hot mantle may provide the heat source for migmatites and initiate the doming of Foping area.

Migmatites provide a record of melt formation and crustal rheology. In this study we present zircon U-Pb ages and geochemical composition of migmatites from the Foping dome and granites from the Wulong pluton. U-Pb results from migmatite zircons indicate two episodes of partial melting. Rim domains from a leucosome in the Longcaoping area yield an age of ca. 209 Ma. Migmatites collected from the Foping dome yield U-Pb zircon ages of ~ 2910 to ~ 190 Ma, suggesting the involvement of meta-sedimentary source components. Rim domains of the zircons with low Th/U ratios ( 2 O and Sr contents than the low Sr/Y granites. They also lack negative Eu anomalies and are depleted in HREE compared to the low Sr/Y granites. Initial 87 Sr/ 86 Sr ratios and e Nd values of all the samples roughly overlap with those of Neoproterozoic basement rocks exposed in South Qinling. Including previous studies, we propose that the high and low Sr/Y granites formed by melting of thickened and normal crust, respectively. Close temporal-spatial relationship of the high and low Sr/Y granites with the two-stage migmatization events implies variation of crustal thickness and thermal overprints of the orogenic crust in post-collisional collapse. Following the collision of South Qinling and the Yangtze block prior to 219 Ma, partial melting of the deep crust occurred. The melts migrated upwards to form the high Sr/Y granites. This process occurred rapidly and caused collapse of the thickened crust and carried heat upwards, leading to further partial melting within the shallower crust and formation of the low Sr/Y granites.

Cu–Au mineralization in the Yangtze River belt is closely related to the formation of adakitic rocks. The origin of these rocks is still controversially discussed. In this study, we report zircon U–Pb ages, major-trace element and Pb–Sr–Nd isotopes of Cu–Au related adakitic rocks from the Anqing and Tongling areas of the lower Yangtze River belt (LYRB). Geochemically, the rocks show similarities to adakites derived from slab melting. Statistical evaluation of existing zircon U–Pb data from the LYRB reveals a protracted magmatic activity from 148 Ma to 106 Ma with peak activity at ~ 139 Ma. Cu–Au related magmatism tends to decrease in age from the southwest (Gan-Hang belt) to the northeast (LYRB). This trend was probably imposed by a roll-back process of the paleo-Pacific plate. The Cu–Au related adakitic rocks in the Gan-Hang belt and the middle and lower Yangtze River belt show systematic variation in geochemical and Pb–Sr–Nd isotopic compositions, pointing to a change in magma composition with time. The rocks have features in common with Cenozoic slab-derived adakites, but have experienced different extents of melt peridotite interaction and complex crustal assimilation processes. AFC modeling shows that input of crustal material increased with time. Combined with the decrease of estimated copper reserves, it is concluded that this records a diminishing influence of slab-derived components during the course of the paleo-Pacific subduction process.

In this paper, polystyrene-based monoliths with highly ordered macroporous structure were synthesized by using SiO2 colloidal crystal as template. SEM observation shows that the macropores are highly ordered and are interconnected by small windows. The BET surface area of PS monolith is about 36.17 m2/g. The polymer monoliths can resist 5 MPa pressure, showing high mechanical and compressive strength.

Amyloid β peptide plays a critical role in the pathogenesis of Alzheimer's disease (AD). Transition metals, such as Cu(II), Zn(II), and Fe(III) are found in Aβ plaques, and they have been shown to affect Aβ aggregation. Here we investigated the interactions between metal ions and Aβ1–16 by a flow-injection surface plasmon resonance spectrometry (SPR). Our study revealed that both Zn(II) and Cu(II) promoted human Aβ1–16 conformation change but the Zn(II)-induced conformation change is greater. However, rat Aβ1–16 binds Zn(II) less avidly and hardly any conformation change, this may due to three point substitutions, R5G, Y10F, and H13R in rat Aβ1–16 which appear to alter the physicochemical properties of the peptide.

The paper presents an on-line transient moving chemical reaction boundary (MCRB) method for simply but efficiently stacking analytes in capillary electrophoresis (CE). The CE technique was developed for a rapid determination of fumaric and maleic acid. Based on the theory of MCRB, Effects of several important factors such as the pH and concentration of running buffer and the conditions of stacking analytes were investigated to acquire the optimum conditions. The optimized separations were carried out in a 20 mmol/L sulphate neutralized with ethylenediamine to pH 6.0 electrolytes using a capillary coated with poly (diallyldimethylammonium chloride) and direct UV detection at 214 nm. The optimized preconcentrations were carried out in 50 mmol/L borax (pH 9.0). The calibration curves were linear in the concentration range of 1.0×10⁻⁷-1.0×10⁻⁴ mol/L and 5.0×10⁻⁷-1.0×10⁻⁴ mol/L for fumaric and maleic acid with correlation coefficients higher than 0.9991. The detection limits were 5.34×10⁻⁸ mol/L for fumaric acid and 1.92×10⁻⁷ mol/L for maleic acid. This method was applied for determination of fumaric acid in apple juice and of fumaric and maleic acid in dl-malic, the recovery tests established for real samples were within the range 95-105%. This work provided a valid and simple approach to detect fumaric and maleic acid.

Optic neuritis is a common disease in young adults, inducing apoptosis of retinal ganglion cells, which leads to varying degree of visual function damages, even blindness. As the standard treatment, methylprednisolone pulse therapy can only promote the recovery of visual acuity but not prevent retinal ganglion cell degeneration. It cannot help improve the ultimate visual outcome. Both inflammatory response and endogenous oxidative stress play crucial roles in the progression of optic neuritis. The combination of immunomodulatory and antioxidant is expected to improve the prognosis of the disease by preventing the apoptosis of retinal ganglion cells. Triterpenoids (oleanolic acid derived) were reported to have the dual capacity of simultaneously repressing production of pro-inflammatory mediators and exerting neuroprotective effects through induction of anti-oxidant genes in experimental optic neuritis. Gypenosides with an aglycone mainly of dammarane-type tetracyclic triterpenoids, also has the dual capacity of immune regulation and antioxidation. Both gypenosides and oleanolic acid were reported to have similar roles in hepatoprotection. Beside, gypenosides were reported to have the capacity of modulating the activation of immune cells and the expression of cytokines. In addition, gypenosides showed neuroprotective effect against oxidative injury in dopaminergic neurons and mouse model of Parkinson's disease. Accordingly, we propose that gypenosides have potential neuroprotective and immunomodulatory effects on optic neuritis through antioxidation and immune regulation. The application of gypenosides might prevent the apoptosis of retinal ganglion cells and improve the ultimate visual outcome in patients with optic neuritis.

Molecularly imprinted polymers (MIPs) are tailor-made polymers with high selectivity for the template molecule. This selectivity arises from the synthetic procedure followed to prepare the MIP. In this work, the influence of process parameters on the preparation of vinblastine (VLB) imprinted polymers was presented. In the procedure of polymerization, VLB (0.1 mmol) was used as the template molecule and a commonly used initiator, azobisisobutyronitrile (AIBN), was employed to initiate the reaction at 60 °C. The influence of the following parameters was investigated: the moles of functional monomer (MAA, 0.3–1.0 mmol), the moles of cross-linker (EDMA, 1.5–5.0 mmol) and the porogenic solvent (toluene or acetonitrile). A mathematical method of uniform design was applied to optimize these selected parameters in order to increase the selectivity of MIP for template molecule. The experimental data were analyzed to obtain the regression model and the optimal conditions were achieved by optimization with uniform design software. The MIP was synthesized under the optimal conditions that 1.0 mmol of MAA and 5.0 mmol of EDMA copolymerized in toluene in the presence of 0.1 mmol of VLB. After removal of the template molecule, the obtained MIP was then employed as the sorbents of solid-phase extraction (SPE) to separate VLB from Catharanthus roseus extract. The results showed that the polymer exhibited high affinity to the template molecule and could separate and enrich VLB from C. roseus extract effectively. The recovery of VLB on the optimal MIP was 89.00%, which agreed closely with the predicted recovery. Therefore it is possible to further improve the nature of the polymer by optimizing the polymerization parameters with the method of uniform design.

A series of molecularly imprinted polymers (MIPs) was prepared using quinine as the template molecules by bulk polymerization. The presence of monomer–template solution complexes in non-covalent MIPs systems has been verified by both fluorescence and UV–vis spectrometric detection. The influence of different synthetic conditions (porogen, functional monomer, cross-linkers, initiation methods, monomer–template ratio, etc.) on recognition properties of the polymers was investigated. Scatchard analysis revealed that two classes of binding sites were formed in the imprinted polymer. The corresponding dissociation constants were estimated to be 45.00 μmol l−1 and 1.42 mmol l−1, respectively, by utilizing a multi-site recognition model. The binding characteristics of the imprinted polymers were explored in various solvents using equilibrium binding experiments. In the organic media, results suggested that polar interactions (hydrogen bonding, ionic interactions, etc.) between acidic monomer/polymer and template molecules were mainly responsible for the recognition, whereas in aqueous media, hydrophobic interactions had a remarkable non-specific contribution to the overall binding. The specificity of MIP was evaluated by rebinding the other structurally similar compounds. The results indicated that the imprinted polymers exhibited an excellent stereo-selectivity toward quinine.

Bilateral acute optic neuritis (AON) is rare in adults in Western countries, but is relatively common in Asian populations. We aimed to document clinical features in Chinese patients with bilateral AON, and to identify factors that are predictive of visual acuity outcome. We reviewed 41 patients (23 males, 18 females; age 18-74 years) diagnosed with bilateral AON from three centers between 2003 and 2009. Demographic and clinical data were compared to a group of patients with unilateral AON. Univariate analysis and multivariate linear regression were used to identify prognostic factors. We found that the median visual acuity (expressed as the logarithm of the minimal angle of resolution [LogMAR] scores) in our patients was 1.55 at presentation and 0.72 at discharge (p

To describe the clinical profile of unilateral optic neuritis (ON) in a Chinese population, we reviewed retrospectively the records of 100 patients (66% female; age 18-74 years) diagnosed with unilateral ON between 2003 and 2009 at three hospitals in Guangxi Province, China. Ocular pain was noted in 40% and disc swelling in 48%. Periventricular plaques were found in 8% and multiple sclerosis in 6%. Visual loss varied at presentation, being mild (≥ 0.5) in 15%, moderate (0.1-0.4) in 26%, and severe (0.1) in 59%. Visual acuity improved after a mean (± standard deviation) hospitalization of 12.5 ± 5.3 days, with visual loss eing mild in 52%, moderate in 14% and severe in 34%. Our findings suggest that the characteristics and severity of initial visual loss of patients in our study are more similar to those of patients in Japan than to those of patients in the United States of America. It seems that visual recovery in our patients is relatively good.