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Abstract: Ruggedness and robustness testing is applied prior to the transfer of a method to various laboratories. It is especially important for official methods that are widely and formally used. Ginsenosides (Rg1, Re, Rf, Rb1, Rg2, Rc and Rd) occurring in Asian and American ginseng, were assayed using high-performance liquid chromatography (HPLC) methods issued by the United States Pharmacopoeia (USP XXVI and XXVII). They have a delicate system suitability to properly execute the method. A robustness test was carried out using an experimental design approach, in order to indicate the suitability of the method in a broad execution range. Seven factors are selected and examined by a fractional factorial design. Twelve responses, involving quantitation-related items, such as recovery of Rg1 and Rb1, and qualitative items, such as resolution (Rs), theoretical plate number (N), relative retention time (RRT) of two critical pairs, are measured. The calculated effects are both graphically and statistically interpreted to identify the significant factors. The robustness tests using fractional factorial design on the assay of ginsenosides provided an effective approach as part of a validation of the method on phytomedicines. It also indicated that methods with different selectivity, of which some are possibly unsuitable, could pass the existing system suitability limits. [Copyright &y& Elsevier]

Abstract: Soil and weather data are critical for the operation of crop simulation models. However, in many cases they are not readily available, especially applications at a regional or larger spatial scale. The Vegetation/Ecosystem Modeling and Analysis Project (VEMAP) provides massive quantities of geo-referenced soil and weather data variables on a half-degree latitude–longitude grid covering the conterminous USA. The VEMAP data were derived from a range of products and analyses, including ground observations, cluster analyses, kriging interpolation, and data assimilation. The objective of this study was to convert the soil and daily weather data of VEMAP into a format that can be used in the popular modeling software Decision Support System for Agrotechnology Transfer (DSSAT). Users can select appropriate soil or daily weather information for the area of interest. The conversion of the VEMAP data resulted in 5927 unique soil profiles and 3261 unique weather station files that encompass daily data from 1895 to 1993. To demonstrate the utility of this database in DSSAT, one representative county of the state of Georgia, USA was selected and a soybean simulation model was employed to simulate final yield using the extracted soil and daily weather data for the normal year (1961–1990). Meanwhile, the extracted daily weather data were compared with ground station observations from the National Weather Service Cooperative Observer Program (COOP). The paired t-test showed that no significant differences were found between the daily weather data and between simulated yields based on VEMAP and COOP weather data for the selected location. The outcome of this research showed that the VEMAP data can be used for crop model applications. However, further research is needed to assess the accuracy of the datasets for a variety of crops at a regional or national scale. [Copyright &y& Elsevier]

• Most of the natural geographical distribution of Nulembo lutea was sampled. • Low level of genetic diversity was revealed in American lotus populations. • High genetic differentiation and strong population structure was observed. • Low level of gene flow among the genetic pools was revealed. American lotus (Nelumbo lutea Willd.) is a popular plant with ornamental, medicinal, and culinary value. Studies related to the genetic diversity and population structure of N. lutea are limited. We sampled 326 individuals from 19 populations of wild N. lutea across its distribution range in the USA and genotyped them using 12 microsatellite markers. A total of 274 alleles were amplified by 12 microsatellites with a mean of 22.83. We observed a low level of genetic diversity for American lotus (A e = 2.40 and H E = 0.459) in the USA. The analysis of molecular variance (AMOVA) exhibited closer variation among populations (42.00%) than within populations (58.00%) of N. lutea, with strong genetic differentiation observed (F ST = 0.419). There was no significant correlation between genetic and geographic distances. The Bayesian analysis and neighbor-joining dendrogram displayed strong population structure. A very low level of historical gene flow (N M = 0.073) was observed among the populations. Fourteen of the 19 populations showed a demographic bottleneck, indicating the vulnerability of the American lotus populations. We thus proposed priority population sites for the conservation of N. lutea via both ex-situ and in-situ techniques. [ABSTRACT FROM AUTHOR]