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One of the most important problems concerning the toll roads is the setting of an appropriate cost for traveling through private arcs of a transportation network. The purpose of this paper is to consider this problem by stating it as a bilevel programming (BLP) model. At the upper level, one has a public regulator or a private company that manages the toll roads seeking to increase its profits. At the lower level, several companies-users try to satisfy the existing demand for transportation of goods and/or passengers, and simultaneously, to select the routes so as to minimize their travel costs. In other words, what is sought is kind of a balance of costs that bring the highest profit to the regulating company (the upper level) and are still attractive enough to the users (the lower level).

With the aim of providing a solution to the BLP problem in question, a direct algorithm based on sensitivity analysis (SA) is proposed. In order to make it easier to move (if necessary) from a local maximum of the upper level objective function to another, the well-known “filled function (FF)” method is used.

The paper proposes and tests two versions of the heuristic algorithm to solve the toll optimization problem (TOP) based upon SA for linear programming (LP) problems. The algorithm makes use of an SA procedure for the LP problem at the lower level, as well as of the “filled” function technicalities in order to reach the global optimum when “jammed” at some local optimum. Numerical experiments with a series of small and medium dimension test problems show the proposed algorithm’s robustness and decent convergence characteristics.

Numerical experiments with a series of small- and medium dimension test problems show the proposed algorithm’s robustness and reasonable convergence characteristics. In particular, while ceding in efficiency to other algorithms when solving small problems, the proposed method wins in the case of medium (higher dimensional) test models. Because of that, one can expect a serious real-life impact on the TOP when the proposed methods and/or their improved versions are developed further to be applicable in practice in the near future.

The proposed algorithms are original and perform well when solving small and medium test numerical problems. The proposed heuristics aim at filling in a gap in a series of numerical approaches to the solution of TOP problem listed in the Introduction. To the authors knowledge, no systematic attempts to apply the SA tools to the toll assigned problem have been recently made. Moreover, the combination of these powerful tools with the “FFs” techniques brings forward some new global optimization ideas. Exactly these features build up the knowledge this specific paper offers in relation to previous relevant works.

This book is an attempt to reflect on what we have learned from financial policies and financial crises in Latin America. The 21 chapters in this volume capture the developments in various ways. They cover theoretical contributions, regional empirical studies, and specific inquiries on Argentina, Brazil, Chile, Colombia, Cuba, Ecuador, Mexico, Peru and Venezuela. The breadth of methodologies implemented suggests that researchers are looking at Latin American financial markets through a variety of lenses. The chapters are divided into 7 parts, including, in Part I, an initial overview. Part II examines the foreign exchange markets in Latin America and their interactions with other markets. Part III discusses dollarization issues in the region. Part IV then takes up the issue of banking in Latin America. Equity and bond markets are considered in Parts V and VI, respectively. Lastly, Part VII considers pension systems in Latin America. Taken as a whole, the 21 chapters seize the excitement of studying Latin America and provide lessons that are applicable around the world.

This paper aims to determine the impact of in vitro gastrointestinal digestion (IVD) on the bioaccessibility of phenolic compounds derived from tomato pomace flour (TPF) and amla pomace flour (APF), and to evaluate their potential health benefits as prebiotics on gut microbiota.

The nutritional and functional properties and the bioaccessibility of phenolic compounds obtained from APF and TPF were measured using IVD model and the potential prebiotic effects were assessed during in vitro fermentation.

APF and TPF contained significant amounts of total dietary fibre (55.83% and 48.29%, respectively) and protein (2.1% and 14.37%, respectively). After IVD, a considerable amount of polyphenols from APF and TPF were released. In the intestinal phase, APF and TPF showed significant (p = 0.05) release of total phenolics (81% and 57%, respectively) and flavonoids (84% and 76%, respectively). Additionally, in comparison to the control samples, IVD increased antioxidant capacity. The proliferation of bacteria (L. acidophilus) and the production of short-chain fatty acids (SCFAs), including propionate and butyrate, were both increased during in vitro fermentation of APF and TPF. Both the flours showed a positive prebiotic activity with the value of <1.50.

The study supports sustainable agriculture and global pollution reduction. Incorporating these by-products into diets might increase the availability of inexpensive, nutritious food choices, improve digestive health and create economic possibilities for food producers and farmers.

The research provides novel information on the bioaccessibility of polyphenols and antioxidants during digestion, and the prebiotic potential APF, which have not been previously documented.