The genus Sipha Passerini (Hemiptera: Aphididae) in North America

Five species of the aphid genus Sipha Passerini (Hemiptera: Aphididae) are reported in North America and are reviewed herein. Of these species, three are adventive species and include: Sipha elegans del Guercio, Sipha glyceriae (Kaltenbach), and Sipha maydis Passerini. Sipha maydis was discovered in California in 2007 and now has been found in Georgia. The genus also includes two native species: Sipha agropyronensis (Gillette) and Sipha flava (Forbes). Sipha maydis can be distinguished easily from all the other species in the genus that occur in North America because it is black. All the species except S. agropyronensis have been implicated in damage to crop plants. A key to the apterae and alatae of Sipha found in North America is included

Use of mathematical derivatives (time-domain differentiation) on chromatographic data to enhance the detection and quantification of an unknown 'rider' peak

Two samples of an anticancer prodrug, AQ4N, were submitted for HPLC assay and showed an unidentified impurity that eluted as a 'rider' on the tail of the main peak. Mathematical derivatization of the chromatograms offered several advantages over conventional skimmed integration. A combination of the second derivative amplitude and simple linear regression gave a novel method for estimating the true peak area of the impurity peak. All the calculation steps were carried out using a widely available spreadsheet program. (C) 2003 Elsevier B.V. All rights reserved

Flexible Tool for Model Building: the Relevant Transformation of the Inputs Network Approach (RETINA)

A new method, called Relevant Transformation of the Inputs Network Approach (RETINA) isproposed as a tool for model building. It is designed around flexibility (with nonlinear transformations of the predictors of interest), selective search within the range of possible models, out-of-sample forecasting ability and computational simplicity. In tests on simulated data, it shows both a high rate of successful retrieval of the DGP which increases with the sample size and a good performance relative to other alternative procedures. A telephone service demand model is built to show how the procedure applies on real data.Relevant Transformation of the Inputs Network Approach (RETINA), Economics models

A flexible Tool for Model Building: the Relevant Transformation of the Inputs Network Approach (RETINA)

A new method, called relevant transformation of the inputs network approach (RETINA) is proposed as a tool for model building and selection. It is designed to improve some of the shortcomings of neural networks. It has the flexibility of neural network models, the concavity of the likelihood in the weights of the usual likelihood models, and the ability to identify a parsimonious set of attributes that are likely to be relevant for predicting out of sample outcomes. RETINA expands the range of models by considering transformations of the original inputs; splits the sample in three disjoint subsamples, sorts the candidate regressors by a saliency feature, chooses the models in subsample 1, uses subsample 2 for parameter estimation and subsample 3 for cross-validation. It is modular, can be used as a data exploratory tool and is computationally feasible in personal computers. In tests on simulated data, it achieves high rates of successes when the sample size or the R2 are large enough. As our experiments show, it is superior to alternative procedures such as the non negative garrote and forward and backward stepwise regression.

A Method For Microbial Surface Sampling: Developing and Applications

A method for assessing microbial contamination on surfaces is presented, and its development is discussed. Further, some applications in hospital and aerospace studies are describe

Key to Florida Alydidae (Hemiptera: Heteroptera) and selected exotic pest species

A key to the fourteen native Florida species and seven exotic pest species of Alydidae is presented here. The key uses external, non-genitalic morphology and allows for rapid separation of the native species and exotic pests included herein

Key to Florida Alydidae (Hemiptera: Heteroptera) and selected exotic pest species

A key to the fourteen native Florida species and seven exotic pest species of Alydidae is presented here. The key uses external, non-genitalic morphology and allows for rapid separation of the native species and exotic pests included herein

Rheology to guide formulation development of particulate dispersions for automated capsule filling

The rheological properties of pharmaceutical formulations intended for liquid fill hard gelatin capsules are fundamental for their filling performance. Here we used the rheological characteristics of particulate drug formulations to develop formulations suitable for automated capsule filling

Occurrence of the Old World bug Megacopta cribraria (Fabricius) (Heteroptera: Plataspidae) in Georgia: a serious home invader and potential legume pest

Specimens of Megacopta cribraria (Fabricius) were collected in northern Georgia in late October 2009, where they were invading homes in large numbers. This is the first known occurrence of this species and the family Plataspidae in the New World. Megacopta cribraria was previously known from Asia and Australia. A key is provided to separate Plataspidae from other families of Pentatomoidea in America North of Mexico. A diagnosis and figures are provided to facilitate recognition of M. cribraria. Reported host plants and other aspects of the biology of this species are reviewed. Megacopta cribraria is considered a pest of numerous legumes in Asia, has the potential to provide biological control of kudzu, Pueraria montana var. lobata (Willd.) Ohwi, (Fabaceae) and likely will continue to be a household pest in the vicinity of kudzu fields as well as become a pest of North American legume crops