Transparency in the food chain : policies and politics

The dissertation is organised in four parts. The first part (Chapter 2) sets the background. It explores the status quo and explains the need for transparency in the food chain. This chapter argues that transparency is a condition for responding to the set of changes that occurred in the food system during the last decades. The second part (Chapters 3, 4 and 5) presents the theoretical approaches that this dissertation draws on as well as the analytical perspective and methods used. Chapter three examines the theories and approaches most valuable for analyzing the process of promoting transparency in a multi-actor context. Having reviewed the major approaches, the dissertation¿s own analytical perspective is presented in chapter four. We view the formation of policy outputs for transparency, as a result of both actor strategies and network structures. More specifically, the network is considered to set the context within which individual strategies can evolve. The way actors and network characteristics are operationalised and measured is presented in chapter five. We also present the dissertation¿s methodology for the collection as well as analysis of data and case selection in this chapter. The third part (Chapters 6, 7, 8 and 9) presents the empirical analyses. Putting the model into force, chapters six and seven assess the political feasibility of efforts to improve transparency in the pork chain in the Netherlands and the EU respectively. In a similar vein, chapters eight and nine focus on the farmed-fish chain in the Netherlands and the EU respectively.\ud Finally, the fourth part (Chapter 10) concludes the dissertation, interprets the results and discusses their implications for transparency and sustainability related policies and politics

Alexander polynomial, finite type invariants and volume of hyperbolic knots

We show that given n>0, there exists a hyperbolic knot K with trivial Alexander polynomial, trivial finite type invariants of order <=n, and such that the volume of the complement of K is larger than n. This contrasts with the known statement that the volume of the complement of a hyperbolic alternating knot is bounded above by a linear function of the coefficients of the Alexander polynomial of the knot. As a corollary to our main result we obtain that, for every m>0, there exists a sequence of hyperbolic knots with trivial finite type invariants of order <=m but arbitrarily large volume. We discuss how our results fit within the framework of relations between the finite type invariants and the volume of hyperbolic knots, predicted by Kashaev's hyperbolic volume conjecture.Comment: Published by Algebraic and Geometric Topology at http://www.maths.warwick.ac.uk/agt/AGTVol4/agt-4-48.abs.htm

Knot adjacency and satellites

A knot K is called n-adjacent to the unknot, if K admits a projection containing n generalized crossings such that changing any m (no larger than n) of them yields a projection of the unknot. We show that a non-trivial satellite knot K is n-adjacent to the unknot, for some n>0, if and only if it is n-adjacent to the unknot in any companion solid torus. In particular, every model knot of K is n-adjacent to the unknot. Along the way of proving these results, we also show that 2-bridge knots of the form K_{p/q}, where p/q=[2q_1,2q_2] for some integers q_1,q_2, are precisely those knots that have genus one and are 2-adjacent to the unknot.Comment: 13 pages, 3 figures. to appear in Topology and Its Application