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The most striking Lincang granitic batholith widely distributed in the Sanjiang Paleo-Tethys Orogen provides us a crucial window to understand the subduction, consumption, and associated geodynamic mechanism of the Paleo-Tethys Ocean during the late Paleozoic to early Mesozoic. In this study, we carry out an integrated study of petrology, zircon U-Pb geochronology, whole-rock major and trace elements, and in situ zircon Hf isotope of the Late Triassic granitic rocks from the Lincang granitic batholith, with the aim of investigating their geochronological framework, spatio-temporal variations, genetic mechanism, and tectonic significance. The granitic rocks presented in this study consist of granodiorite and monzogranite, with minor syenogranite. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) zircon U-Pb dating of these granitic rocks yield crystallization ages of 237.6–209.0 Ma, indicating multi-stage granitic magmatic activities during the Late Triassic. Geochemical analyses show that these granitic rocks belong to medium-K calc-alkaline and shoshonite series, and have metaluminous to peraluminous characteristics and low whole-rock zircon saturation temperature (726–834°C). The Late Triassic granitic rocks show transitional characteristics and originate from different magma sources, indicative of transitional I-type and S-type granite affinities. The 237.6 Ma gneissic granodiorites belong to I-type granite and have typical continental arc granites of enrichments in large ion lithophile elements (Rb, K, Pb, and Th) and light rare earth elements (LREEs), and depletion in high field strength elements (Nb, Ta, Ba, Ti, and P) and heavy rare earth elements (HREEs), with parental magma derived from garnet amphibolite facies lower crust. Whereas the 222.7–209.0 Ma granitic rocks have S-type granite affinities with psammitic source. The transitional geochemical characteristics led us to favour that syn-collisional stage in response to final closure of the Paleo-Tethys Ocean in Southwestern Yunnan lasted at least until 237.6 Ma. Subsequent extensional mechanism and associated asthenosphere upwelling after final closure of the Paleo-Tethys Ocean induce large-scale partial melting of the middle-lower crust, resulting in voluminous generation of S-type and A-type granitic rocks and associated volcanic rocks in Southwestern Yunnan. [ABSTRACT FROM AUTHOR]

Modern analogues of Archaean charnockite are important because they facilitate investigations into processes of early crustal formation and tectonic transition. Herein, we present the results of the petrography, geochemistry, and isotope geochronology of Late Neoarchean charnockites in the Daqingshan terrane at the northern margin of the North China Craton. The sources, petrogenesis, and tectonic implications of the samples obtained are determined based on their geochemical characteristics. Charnockites mainly exhibit magnesian and calc–alkaline characteristics; furthermore, they contain high amounts of light rare-earth elements, with slightly positive Eu anomalies. Analysis of zircon U–Pb dating using a sensitive high-resolution ion microprobe reveals that Hademengou–Xiwulanbulang (HDMG–XWLBL) charnockites were emplaced during the (i) Late Neoarchean (ca. 2500 Ma), with zircon εHf(t) values ranging from 1.57 to 7.81; (ii) single-stage model ages (TDM1) from 2529 to 2637 Ma; and (iii) two-stage model ages (TDM2) from 2710 to 2820 Ma. A comparative study has performed on the petrography, geochemistry, and geochronology of charnockite and granulite shown that the parent magma of the charnockites is the product of the partial melting of granulite. Combining our results with geological data pertaining to the Archaean structural evolution of the Daqingshan terrane, we speculate that the Late Neoarchean HDMG–XWLBL charnockite was formed during a subduction-related thermo-tectonic event in the northern margin of the North China Craton. [ABSTRACT FROM AUTHOR]

S-type granites constitute an important component of the Paleoproterozoic Khondalite Belt in the North China Craton. Here we present results from petrography, geochemistry and isotope geochronology on the porphyritic garnet-bearing syenogranite and garnet-bearing monzogranite samples in the Jining-Liangcheng area. The geochemical characteristics of these samples indicate formation through partial anatexis of the khondalites, with heat and material input from mantle-derived magma. Geochemical similarities between the porphyritic garnet-bearing syenogranite, garnet-bearing monzogranite, and metapelitic gneiss suggest their broad affinity. Sensitive high-resolution ion microprobe zircon U–Pb dating revealed that the S-type granites formed at ca. 1.92–1.90 Ga and were subsequently metamorphosed at ca. 1.85 Ga. The ca. 1.92–1.91 Ga porphyritic garnet-bearing syenogranite shows zircon εHf(t) values of −1.94–+3.38 with two-stage Hf crustal model ages (TDM2) ages of ca. 2.42–2.59 Ga. The 1.91–1.90-Ga garnet-bearing monzogranites show zircon εHf(t) values ranging from −4.36 to +0.38, with TDM2 ranging from ca. 2.57 to ca. 2.82 Ga. The geochemical isotopic compositions suggest that the porphyritic garnet-bearing syenogranite and garnet-bearing monzogranite originated from the partial melting of pre-existing crust of heterogeneous compositions with the addition of mantle-derived material. On the basis of our results, combined with geological data on the Paleoproterozoic structural evolution of the Khondalite Belt, we assume that the timing of the metamorphism and anatexis in the Jining–Liangcheng area is correlated with a regional metamorphism and mantle-derived magmatism. [ABSTRACT FROM AUTHOR]

Three series of sulfonate derivatives of paeonol were synthesized and screened in vitro for their anti-oomycete activity against P. capsici, respectively. Among all the compounds, 4m displayed the best promising and pronounced anti-oomycete activity against P. capsici than zoxamide, with the EC50 values of 24.51 and 26.87 mg/L, respectively. The results show that acetyl and 4-OCH3 are two necessary groups. The existence of these two sites is closely related to the anti-oomycete activity. Relatively speaking, hydroxyl group is well tolerated, and the results showed that after modification of hydroxyl group with sulfonyl, the anti-oomycete activity was significantly increased. [ABSTRACT FROM AUTHOR]

The novel allenylphosphinates containing up to three axial and phosphorus asymmetric centers were prepared in excellent yields via the reactions of 6-chloro-6 H-dibenzo[ c, e][1,2]oxaphosphinine to propargyl alcohols. During the process, the configuration of phosphorus determined the biphenyl axial chirality, stereospecifically forming ( l)-stereomers but did not influence the chirality of allenyl axis. [ABSTRACT FROM AUTHOR]

Quartz diorite intrusions in the Jiefangyingzi area associated with deformed Palaeozoic rocks of the Palaeozoic Bainaimiao arc magmatic belt on the northern margin of the North China Craton (NCC) were studied to determine their age, chemical composition, and isotopic characteristics. U–Pb dating of magmatic zircons indicates that the quartz diorites formed in Neoarchaean time between 2502.6 ± 9.1 Ma and 2551 ± 7.3 Ma. The quartz diorites have high Al2O3and low K2O contents, A/CNK = 0.75–0.97, and belong to the low-K tholeiitic series. The quartz diorites are enriched in light rare earth elements (LREEs) with high (La/Yb)Nratios and exhibit weak positive or no Eu anomalies, characteristics of high-alumina tonalite–trondhjemite–granodiorite (TTG) igneous rocks. ZirconεHf(t) value for the quartz diorites ranges from +1.6 to +8.7, and the two-stage Hf-depleted mantle model age (TDM) ranges from 2705 to 2744 Ma, suggesting that the quartz diorite was derived from melting juvenile Neoarchaean crust formed from partial melting of the mantle at 2.7 Ga. Amphibolite xenoliths have low REE concentrations and are moderately depleted in LREE with (La/Yb)Nratios of 0.46–1.09. The trace element characteristics of the amphibolites are consistent with a mid-ocean-ridge basalt (MORB)-like protolith. This is the first time that Archaean rocks have been identified in the Bainaimiao arc magmatic belt and the age and nature of Jiefangyingzi quartz diorites suggest that they belonged to the NCC. The Early Palaeozoic Bainaimiao arc thus appears to represent an Andean-type continental arc on the northern margin of the NCC. [ABSTRACT FROM AUTHOR]

In his monograph River System Li Daoyuan put forward the conception of ecological protection which went unheard in academic circles for long. According to Li, water itself is something of reason and spirituality and affects mankind in light of their choices; people may take their initiatives when they exploit the natural world on condition that they must respect the objective laws. If the world is over-exploited or polluted, it is mankind itself that will suffer retaliation. This ecological concept gives people theoretical but useful references for ecological protection and help carry out the outlook of scientific development. [ABSTRACT FROM AUTHOR]

Aromatic methyl ketones and cyclic asymmetric ketones underwent hydrophosphorylation with P-stereogenic H-P species in the presence of potassium carbonate to produce P,C-stereogenic tertiary α-hydroxyl phosphinates in excellent yields with up to 99 : 1 dr. The diastereoselectivity was induced by a reversible conversion of less stable stereomer of product to that of a more stable one via an equilibrium, which was confirmed by aldehyde/ketone exchanging reaction. Toward the exchange, aliphatic or aldehyde carbonyl were more active than aromatic or ketone carbonyls, respectively. The stability difference between the two diastereomers was controlled by the sizes of substituents linking to phosphorus or α-carbon.

The molecule of the title compound, C(32)H(48)O(4)P(2)S(2), has 2 symmetry, the mid-point of the S-S bond being located on a twofold rotation axis. The two tetra-hedral P units are linked by a S-S bond with a P-S-S-P torsion angle is 131.19 (6)°. The dihedral angle between two phenyl rings is 12.66 (13)°. The cyclo-hexane ring of the menthoxyl group displays a chair conformation. Weak inter-molecular C-H⋯O hydrogen bonding is present in the crystal structure.

Objective: To investigate the effect of imatinib on rat C6 glioma cell apoptosis and cell cycle., Methods: MTT assay was used to determine the OD value of C6 glioma cells following treatment with imatinib at different concentrations (0.156, 10 and 15 micromo/L) for 24, 48 and 72 h. The cell apoptosis was assayed by Hochest/PI staining and the cell cycle changes were analyzed by flow cytometry., Results: Imatinib treatment resulted in increased number of apoptotic cells in a time- and dose-dependent manner. A 72-h treatment of the cells with imatinib at 10 and 15 micromo/L caused increased cell percentage in G(0)/G(1) phase to (68.53-/+0.83)% and (70.41-/+0.62)%, (P<0.01), decreased the percentage of G(2) phase cells to (14.48-/+0.12)% and (13.84-/+2.86)% (P<0.01), and decreased the percentage of S phase cells to (16.98-/+0.72)% and (15.78-/+2.28)%, respectively (P<0.01)., Conclusion: Imatinib can induce apoptosis and affect the distribution of the cell cycle of C6 cells in vitro.

Objective: To establish a qualitative and quantitative reversed-phase high-performance liquid chromatography (RP-HPLC) with fingerprinting technique for quality control of compound dandelion enema., Methods: HPLC was utilized for quality assessment of 10 batches of samples. RP-HPLC analysis was performed on a Hypersil BDS C18 column (4.6 mm x 250 mm, 5 microm) with the mixture of acetonitrile (A) and potassium phosphate solution (B) (pH3.2) as the mobile phase in gradient mode. The concentrations of solvent A were 10%, 80% and 80% at 0, 38 and 40 min, respectively. The column temperature was set at 35 degrees C, the flow rate at 0.7 ml/min and the detection wavelength at 254 nm., Results: HPLC fingerprinting was established from the 10 batches, and the data showed 23 characteristic peaks in the compound dandelion enema for use as index peaks for qualitative identification. Comparison of the retention time and the on-line UV spectra of the samples with the chemical standards identified peaks 3, 4 and 8 as protocatechualdehyde, caffeic acid and ferulic acid, respectively. The contents of caffeic acid in the compound dandelion enema ranged between 63.7 and 136.8 microg/ml., Conclusion: High specific chromatographic fingerprinting and quantitative measurement of caffeic acid allows rigorous quality control of compound dandelion enema.

Objective: To identify the active components of compound dandelion enema, a preparation from 7 traditional Chinese herbal drugs for treatment of gynecological diseases., Methods: Three-dimensional high-performance liquid chromatography (3D-HPLC) was employed to separate the ethyl acetate extract of compound dandelion Enema, and HPLC combined with mass spectrum (MS) analysis used for chromatographic fingerprinting., Result: By comparing the ionic fragments of MS and retention time of each peak, the main active components in compound dandelion enema were determined, including caffeic acid, ferulic acid and protocatechualdehyde., Conclusion: HPLC coupled with mass spectroscopy can be used for qualitative analysis of compound dandelion enema.

Objective: To determine caffeic acid content in Fujie enema and the crude traditional Chinese herbal drug Taraxacum mongolicum Hand.-Mazz. for controlling the quality of the enema at the levels of both the crude drugs and the final product., Methods: Caffeic acid content in both the enema and the crude drug was determined at 313 nm Using high-performance capillary electrophoresis (HPCE), under the optimized conditions achieved with a fused-silica capillary tube (75 micromx0 cm) and 20 mmol/L borate running buffer (pH=9.18) at a constant voltage of 12 kV and a sampling time of 5 s at 25 degrees Celsius., Results: The calibration curve displayed good linear relationship within caffeic acid concentration range of 10 to 100 microg/ml (r=0.999 2). The regression equation was Y=1002.45X-327.87, and the average recovery was more than 95%., Conclusion: HPCE is simple, rapid and sensitive in separation and determination of caffeic acid in Fujie enema and the crude drug of Taraxacum mongolicum Hand.-Mazz.

Objective: To examine the absorption and distribution of 5-aminosalicylic acid (5-ASA) in rat colon after oral administration of its chitosan capsule., Methods: 5-ASA in chitosan capsules (4.8 mg per 3 capsules) were administered orally in rats via a polyethylene cannula under light ether anesthesia. The rats in control group were given 1 ml 5-ASA carboxymethyl cellulose suspension (4.8 mg). Blood samples were obtained from the rat hearts and the colon tissues sampled at a given interval to measure the concentration of 5-ASA by HPLC., Results: The area under the curve (AUC(0-12)) in the serum samples of chitosan capsule group was 0.62 times that of the control group, while in the colon tissue, the AUC(0-12) of chitosan capsule group was as much as 3.62 times that of the control group., Conclusion: The chitosan capsule may be a useful carrier of 5-ASA for colon-specific delivery.