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The Aruhan granodiorite intrusion in Xiwuqi, Inner Mongolia, is exposed along the central and eastern parts of the Hegenshan suture zone. LA-ICP-MS zircon U-Pb dating shows that the ages of the granodiorite are ranging from 332±3 to 327 ±1 Ma, suggesting emplacement during the Early Carboniferous. The Aruhan granodiorite is characterized by high contents of SiO2 (65.20% to 68.27%), Al2O3 (15.61% to 17.35%), Sr (472x10-6 to 552x10-6) and low contents of MgO (1.16% to 1.61%), Yb (0.86x10-6 to 1.13x10-6), Y (7.29x10-6 to 11.42x10-6, with Na2O/K2O and Sr/Y ratios ranging from 2.56 to 4.35 and 43.45 to 75.68, respectively. The total REE is low (44.73x10-6 to 88.11x10-6), the fractionation of REE is significant [(La/Yb)N = 6.65 ~ 13.85], and the anomaly of Eu (δEu = 0.79 to 1.07) is not obvious. The geochemical characteristics of the whole-rock indicate that the Aruhan granodiorite belongs to typical high-SiO2 island arc adakites (O-type) series, formed in an environment of active continental marginal arc. The source of the maga might be the product of partial melting of subducting oceanic crust with oceanic sediments, which reacts with overlying mantle peridotite. Crystallization differentiation and contamination by crustal materials might occurre during its emplacement. This discovery may support the fact that the central and eastern parts of the Hegenshan Ocean was not yet closed during the Early Car-boniferous. Combined with the regional research, we preliminarily believe that the Hegenshan Ocean may have undergone bidirectional subduction and abatement during the Early Carboniferous, which is different from the previous view that the Hegenshan Ocean underwent unidirectional subduction and abatement northward only. [ABSTRACT FROM AUTHOR]

2,7,2′-Trihydroxy-3,4,4′7′-tetramethoxy-1,1′-biphenanthrene (1), a previously undescribed biphenanthrene, and five known phenanthrenes, i.e. 2,5-dihydroxy-4-methoxy-9,10-dihydroxyphenanthrene (2), 2,4-dihydroxy −7-methoxy-9,10-dihydroxyphenanthrene (3), 7-hydroxy-2-methoxy-phenanthrene-1,4-dione (4), 7-hydroxy-2-methoxy-9,10-dihydro-phenanthrene-1,4-dione (5), and 4,4′,7,7′-tetrahydroxy-2,2′-dimethoxy-9,9′,10,10′-tetrahydro−1,1′-biphenanthrene (6) were isolated from the whole plant (stems, leaves, roots and fruits) of Liparis nervosa (Thunb.) Lindl., which is a medicinal plant of the genus Liparis in the Orchidaceae family. The structures of isolates were identified using spectroscopic methods, including NMR and mass spectrometry. Additionally, the cytotoxic potency of all the isolates against human lung cancer A549 cell line was evaluated by an MTT assay. All the isolated compounds showed cytotoxic activities with IC50 values in the range of 10.20 ± 0.81 to 42.41 ± 2.34 μM. The obtained data highlight the importance of L. nervosa as a source of natural lead compounds for cancer therapy. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the cost-effectiveness of the snail control project by environmental modification in order to provide the evidence for quickly interrupting the transmission of schistosomiasis in hilly regions., Methods: Field investigations were carried out. The changes of the snail habitat areas were compared before and after the snail control project. The direct costs of the snail control were calculated. The reduction rates of snail area and snail density were regarded as the evaluation indexes of the effectiveness. The costs for reduction of 1% of snail area and 1% of snail density were used as the unit for cost-effectiveness analysis., Results: After the 15 projects were implemented, there were no snails in 12 areas. The reduction rates of snail areas were 72.22% to 100%. The reduction rates of the snail area and density were both 100% in the areas with digging new ditches to fill up the old ones and building reservoirs. The total cost of 15 projects was 1 450 800 Yuan. The average cost per unit was 0.56 Yuan/m2. After the snail control project by digging new ditches to fill up the old ones was implemented, the costs of snail area and density decreased by one unit were 300 -700 Yuan, by building reservoirs, the costs were 600 -2 600 Yuan, by building fishpond, the costs were 1 200 - 1 500 Yuan, by watershed comprehensive measures, the costs were 900 - 2 700 Yuan. The cost of digging new ditches to fill up the old ones was significantly lower than that of building reservoirs or watershed comprehensive measures, but there was no significant difference between building reservoirs and watershed comprehensive measures., Conclusions: In hilly regions, the implementation of snail control project by environmental modification combined with construction of water conservancy is effective, and the cost-effectiveness of the snail control with digging new ditches to fill up the old ones is excellent.