Activity-guided fractionation of Theobroma grandiflorum ("cupuaçu") seeds resulted in the identification of two new sulfated flavonoid glycosides, theograndins I (1) and II (2). In addition, nine known flavonoid antioxidants, (+)-catechin, (-)-epicatechin, isoscutellarein 8-O-beta-d-glucuronide, hypolaetin 8-O-beta-d-glucuronide, quercetin 3-O-beta-d-glucuronide, quercetin 3-O-beta-d-glucuronide 6' '-methyl ester, quercetin, kaempferol, and isoscutellarein 8-O-beta-d-glucuronide 6' '-methyl ester, were identified. Theograndin II (2) displayed antioxidant activity (IC(50) = 120.2 microM) in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free-radical assay, as well as weak cytotoxicity in the HCT-116 and SW-480 human colon cancer cell lines with IC(50) values of 143 and 125 microM, respectively. While 1 was less active as an antioxidant than 2, the known compounds were more potent in the DPPH assay (IC(50) range 39.7-89.7 microM).

The main task of this study is to introduce a statistical postprocessing algorithm to reduce the bias in the National Centers for Environmental Prediction (NCEP) and Meteorological Service of Canada (MSC) ensemble forecasts before they are merged to form a joint ensemble within the North American Ensemble Forecast System (NAEFS). This statistical postprocessing method applies a Kalman filter type algorithm to accumulate the decaying averaging bias and produces bias-corrected ensembles for 35 variables. NCEP implemented this bias-correction technique in 2006. NAEFS is a joint operational multimodel ensemble forecast system that combines NCEP and MSC ensemble forecasts after bias correction. According to operational statistical verification, both the NCEP and MSC bias-corrected ensemble forecast products are enhanced significantly. In addition to the operational calibration technique, three other experiments were designed to assess and mitigate ensemble biases on the model grid: a decaying averaging bias calibration method with short samples, a climate mean bias calibration method, and a bias calibration method using dependent data. Preliminary results show that the decaying averaging method works well for the first few days. After removing the decaying averaging bias, the calibrated NCEP operational ensemble has improved probabilistic performance for all measures until day 5. The reforecast ensembles from the Earth System Research Laboratory’s Physical Sciences Division with and without the climate mean bias correction were also examined. A comparison between the operational and the bias-corrected reforecast ensembles shows that the climate mean bias correction can add value, especially for week-2 probability forecasts.

Nine tropane alkaloid aromatic esters (1-9) were isolated from the roots of Erythroxylum pervillei by following their potential to reverse multidrug-resistance with vinblastine-resistant oral epidermoid carcinoma (KB-V1) cells. All isolates, including seven new structures (3-9), were evaluated against a panel of human cancer cell lines, and it was found that alkaloids 3 and 5-9 showed the greatest activity with KB-V1 cells assessed in the presence of vinblastine, suggesting that these new compounds are potent modulators of P-glycoprotein. Confirmatory results were obtained with human ovarian adenocarcinoma (SKVLB) cells evaluated in the presence of adriamycin and synergistic studies performed with several cell lines from the NCI tumor panel. The structures of the new compounds were determined using spectroscopic techniques. Single-crystal X-ray analysis was performed on the monoester, tropane-3 alpha,6 beta,7 beta-triol 3-phenylacetate (1).

Two widely used precipitation analyses are the Climate Prediction Center (CPC) unified global daily gauge analysis and Stage IV analysis based on quantitative precipitation estimate with multisensor observations. The former is based on gauge records with a uniform quality control across the entire domain and thus bears more confidence, but provides only 24-h accumulation at ⅛° resolution. The Stage IV dataset, on the other hand, has higher spatial and temporal resolution, but is subject to different methods of quality control and adjustments by different River Forecasting Centers. This article describes a methodology used to generate a new dataset by adjusting the Stage IV 6-h accumulations based on available joint samples of the two analyses to take advantage of both datasets. A simple linear regression model is applied to the archived historical Stage IV and the CPC datasets after the former is aggregated to the CPC grid and daily accumulation. The aggregated Stage IV analysis is then adjusted based on this linear model and then downscaled back to its original resolution. The new dataset, named Climatology-Calibrated Precipitation Analysis (CCPA), retains the spatial and temporal patterns of the Stage IV analysis while having its long-term average and climate probability distribution closer to that of the CPC analysis. The limitation of the methodology at some locations is mainly associated with heavy to extreme precipitation events, which the Stage IV dataset tends to underestimate. CCPA cannot effectively correct this because of the linear regression model and the relative scarcity of heavy precipitation in the training data sample.

Activity-guided fractionation of a stem extract of Mezzettia leptopoda using human oral epidermoid carcinoma (KB) cells led to the isolation of seven highly acylated oligorhamnosides. Four of these constituents are novel, namely, n-octyl 2-O-acetyl-alpha-L-rhamnopyranosyl-(1-->3)-2, 4-di-O-acetyl-alpha-L-rhamnopyranosyl-(1-->3)-4-O-hexanoyl-alpha-L-rh amnopyranoside (mezzettiaside 8) (1); n-octyl 2, 3-di-O-acetyl-alpha-L-rhamnopyranosyl-(1-->3)-4-O-hexanoyl-alpha-L-rh amnopyranoside (mezzettiaside 9) (2); n-octyl 2, 4-di-O-acetyl-alpha-L-rhamnopyranosyl-(1-->3)-4-O-hexanoyl-alpha-L-rh amnopyranoside (mezzettiaside 10) (3); and n-octyl 2,3, 4-tri-O-acetyl-alpha-L-rhamnopyranosyl-(1-->3)-4-O-hexanoyl-alpha-L-r hamnopyranoside (mezzettiaside 11) (4). Three known compounds were identified as mezzettiasides 2 (5), 3 (6), and 4 (7), respectively, previously isolated from this same plant. The structures of novel compounds 1-4 were determined by spectroscopic methods. All the isolates were evaluated against a panel of human cancer cell lines in this study, and compounds 1-2 and 4-7 were found to be weakly cytotoxic toward KB and/or human colon and lung cancer cell lines.

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The consistency of measurements in various wind tunnels is of concern to designers and code writers. This study attempts to quantify the variability of wind effects estimates based on tests conducted at six wind tunnel laboratories. Pressure tap measurements were made on wind tunnel models of four buildings. Comparisons were made between estimated 50th percenttiles of ͑1͒ peak positive moments in a frame section near the knee joint and ͑2͒ peak pressure coefficients of a roof tap nearest a building corner. Modeling of suburban terrain contributes significantly to the variability. Other factors are eave height, wind direction, and frame location within the building. Coefficients of variation were about 10-40%. A subsequent phase of this research entails a detailed analysis of the reasons for the variabilities. The results could help future improvement of wind load factors that account for all relevant uncertainties in the estimation of wind effects and efforts to improve and standardize wind tunnel simulations.

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