Twelve elements (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Sn, Cd and Pb) in 24 sediment samples at eight sites (S1 -S8) from the East China Sea were analyzed with the BCR sequential extraction (SE) protocol to obtain the metal distribution patterns in this region. The results showed that the heavy metal pollutions in S4 and S8 were more severe than in other sampling sites, especially Cd and Pb pollution. In the top sediments at S4 and S8, both the total contents and the most dangerous non-residual fractions of Cd and Pb were extremely high. More than 90% of the total concentrations of V, Cr, Mo and Sn existed in the residual fraction. Fe, Co, Ni, Cu and Zn mainly (more than 60%) occurred in the residual fraction. While Mn, Pb and Cd dominantly presented in the non-residual fractions in the top sediments. The metal distribution patterns with depth and the correlations between total organic carbon (TOC) and the total Fe -Mn content were also investigated. The results showed that, for most of the elements except Fe, the concentration of elements in fraction A in the top sediments was higher than that in other depth. The similar rule was also found in fraction B but not in fraction C. Besides, the distributions of V, Cd in fraction B and Pb, Cd, Cu in fraction C might be affected by TOC. D
Thirteen new oleanane-type triterpenoid saponins, uralsaponins M-Y (1-13), and 15 known analogues (14-28) were isolated from the roots of Glycyrrhiza uralensis Fisch. The structures of 1-13 were identified on the basis of extensive NMR and MS data analyses. The sugar residues were identified by gas chromatography and ion chromatography coupled with pulsed amperometric detection after hydrolysis. Saponins containing a galacturonic acid (1-3) or xylose (5) residue are reported from Glycyrrhiza species for the first time. Compounds 1, 7, 8, and 24 exhibited good inhibitory activities against the influenza virus A/WSN/33 (H1N1) in MDCK cells with IC50 values of 48.0, 42.7, 39.6, and 49.1 μM, respectively, versus 45.6 μM of the positive control oseltamivir phosphate. In addition, compounds 24 and 28 showed anti-HIV activities with IC50 values of 29.5 and 41.7 μM, respectively.
Changes observed in nine meteorological variables obtained from the Three Rivers Source Region (TRSR) between 1960 and 2009 were investigated using a fitted linear model, Mann-Kendall test, moving t-test, and Morlet wavelet. Analysis of the regionally scaled annual series from 1960 to 2009 showed that minimum (T min ), maximum (T max ), mean (T mean ) air temperature, precipitation (P ), potential evaporation (E p ), and sunshine hours (SH ) increased while relative humidity (RH ) and wind speed (W ) decreased. Trends were significant at a 99% confidence level for air temperature and at a 95% confidence level for E p and W . With the exception of SH , regional scale changes observed in all variables in the past decade (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)) when compared to climate norms (means of all climatic variables) from 1961 to 1990 were consistent with their corresponding linear trends from 1960 to 2009. T max , T mean , and drought index (DI ) exhibited one climate jump, T min and RH two, and SH , E p , and W three at a significance level of α = 0.05. On a regional scale, the period from 1986 to 1997 experienced a warmer, drier climate due to higher than average air temperatures, lower P , and higher DI compared to means from 1960 to 2009. The majority of meteorological variables of the TRSR experienced significant (α = 0.05) short periodical cycling between 2 and 5 years. In terms of spatial distribution, seven out of 12 meteorological stations underwent warmer and wetter periods from 1960 to 2009, whereas the other five situated in the southeastern section of the TRSR underwent warmer, drier periods.
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