This paper discusses the construction of inverse solutions with optimal resolution kernels and applications of them in the reconstruction of the generators of the EEG/MEG. On the basis of the framework proposed by Backus and Gilbert [1967], we show how a family of well-known solutions ranging from the minimum norm method to the generalized Wiener estimator can be derived. It is shown that these solutions have optimal properties in some well-defined sense since they are obtained by optimizing either the resolution kernels and/or the variances of the estimates. New proposals for the optimization of resolution are made. In particular, a method termed ''weighted resolution optimization'' (WROP) is introduced that deals with the difficulties inherent to the method of Backus and Gilbert [1967], from both a conceptual and a numerical point of view. One-dimensional simulations are presented to illustrate the concept and the interpretation of resolution kernels. Three-dimensional simulations shed light on the resolution properties of some linear inverse solutions when applied to the biomagnetic inverse problem. The simulations suggest that a reliable three-dimensional electromagnetic tomography based on linear inverse solutions cannot be constructed, unless significant a priori information is included. The relationship between the resolution kernels and a definition of spatial resolution is emphasized. Special consideration is given to the use of resolution kernels to assess the properties of linear inverse solutions as well as for the design of inverse solutions with optimal resolution kernels.

Field beans (faba beans, broad beans, horse beans, ackerbohnen, Vicia faba L.) depress weight of eggs when fed to laying hens. Vicine isolated from field beans has been shown to depress egg weight and hatchability when fed in large amounts. The present study was undertaken to determine the effect of using three varieties of field beans, varying in tannin and total vicines content, at 20% in breeder diets on reproductive performance of hens and associated vicine transfer from the diet to the egg. Data on egg production, feed consumption, egg weight, body weight, egg quality, hatchability, and hen blood chemistry were obtained. Direct spectrophotometric and high pressure liquid chromatographic (HPLC) analyses of field beans, egg albumen, and egg yolk were conducted. Performance of the hens was excellent on all production characteristics except that there was a nonsignificant reduction in egg weight, a significant reduction in egg shell thickness for hens fed all three types of field beans, and a highly significant reduction in hatchability of eggs from hens fed one but not the other two sources of field beans. The hatchability effect was not correlated with vicine or tannin content of the field beans and only traces of vicine were transferred to the egg by the hen from the diet. Although larger amounts of vicine depressed hatchability when injected into fertile eggs, the trace amounts found in eggs from feeding field beans did not account for the reduction in hatchability observed in this study. It is possible that the hydrolysis product of vicine, divicine or the analogous product from convicine, isouramil, or both, may be involved in toxicity, because these substances are known to be the cause of a hemolytic anemia in some humans that suffer from favism due to consumption of field beans.

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