A-B quasiconvexity and implicit partial differential equations

The study of existence of solutions of boundary-value problems for differential inclusions where , is an open subset of , is a compact set, and B is a -valued first order differential operator, is undertaken. As an application, minima of the energy for large magnetic bodies where the magnetization is taken with values on the unit sphere is the induced magnetic field satisfying and is the anisotropic energy density, and the applied external magnetic field is given by , are fully characterized. Setting with , it is shown that E admits a minimizer with if and only if either 0 is on a face of or , where denotes the convex hull of Z. Received: 6 November 2000 / Accepted: 23 January 2001 / Published online: 23 April 2001     

Zur Konstruktion geschlitzter Inzidenzgruppen

In the first part a derivation method for incidence-groups is developed. The connections to the usual derivations of near-rings are shown in part 2 and examples are constructed. We characterize those finite slit incidence-groups with special affine kernel which are derivations of abelian incidence-groups. Applying these results to special classes of finite incidence-groups we show that there are 2-sided non-abelian finite incidence-groups with abelian affine kernel. The class of derivations of abelian finite incidence-groups contains all splitting a-2-sided incidence-groups with abelian kernel and no splitting kernel-2-sided non-2-sided incidence-group with abelian kernel. In the last part the a-2-sided incidence-groups are algebraically described.The results were partly communicated at the Conference on Geometry in March 1971 at the University of Waterloo, Ontario, Canada.     

Regulatory and compliance activities to protect food-allergic consumers in Canada: research in support of standard setting and consumer protection

An overview is presented of the activities of Health Canada and the Canadian Food Inspection Agency (CFIA) in the area of food allergens. Since the 1990s, changes were made in the Food and Drug Regulations in order to better protect allergic consumers by imposing labeling requirements to clearly identify sources of priority food allergens in prepackaged foods. Policies of application as well as risk management strategies are discussed with some statistics on allergen-related food recalls in Canada for the years 1997--2001. Health Canada's allergen method development program is a pioneering research initiative that was developed in the early 1990s in support of the changing Canadian regulatory environment. The objectives and some of the accomplishments of this program are presented. The development of the Canadian Compendium of Allergen Methodologies under a Web-based application to compile data on evaluated allergen detection methods will provide further support to compliance activities nationally, as well as to the international analytical community in both government and the food industry. Some emerging techniques for the confirmation of results generated by enzyme-linked immunosorbent assays are also discussed.     

Stereospecific synthesis of optically active phenylpropylene oxides

The stereospecific lithiation of diastereomeric phenylpropylene oxides has been studied as well as the trapping reaction with electrophiles. The reduction of the cis-alpha-benzoylpropylene oxide to give prevalently the anti-epoxy alcohol has been investigated as well.