PUBLIC-PRIVATE PARTNERSHIPS IN EUROPE: AN UPDATE

This paper offers an updated description of the macroeconomic and sectoral significance of PPPs in Europe, without assessing PPPs from a normative perspective. It shows that, over the past fifteen years, more than one thousand PPP contracts have been signed in the EU, representing a capital value of almost 200 billion euro. While PPPs have in recent years become increasingly popular in a growing number of European countries, they are of macroeconomic and systemic significance only in the UK, Portugal, and Spain. In all other European countries, the importance of investment through PPPs remains small in comparison to traditional public procurement of investment projects. However, PPP procurement is used extensively for major projects and this is spreading out from transport into other sectors.public-private partnership; Europe

Permanence properties of verbal products and verbal wreath products of groups

By means of analyzing the notion of verbal products of groups, we show that soficity, hyperlinearity, amenability, the Haagerup property, the Kazhdan's property (T) and exactness are preserved under taking $k$-nilpotent products of groups, while being orderable is not preserved. We also study these properties for solvable and for Burnside products of groups. We then show that if two discrete groups are sofic, or have the Haagerup property, their restricted verbal wreath product arising from nilpotent, solvable and certain Burnside products is also sofic or has the Haagerup property respectively. We also prove related results for hyperlinear, linear sofic and weakly sofic approximations. Finally, we give applications combining our work with the Shmelkin embedding to show that certain quotients of free groups are sofic or have the Haagerup property.Comment: v5: Corrects some typos. No new results added. Final version, to appear in Groups, Geometry, and Dynamic

Role of coagulation cascade peptides in the regulation of fibroblast proliferation.

Fibroblast proliferation and extracellular matrix deposition play a critical role in tissue repair and fibrosis. These functions are thought to be modulated by cytokines and growth factors, but these mechanisms are only partially understood. Tissue injury is associated with blood vessel disruption and the activation of coagulation cascade factors VII, IX, X and II (prothrombin) which result in the cleavage of blood fibrinogen into a haemostatic fibrin clot. In addition, increased levels of active coagulation cascade factors and fibrin deposition are associated with fibrotic diseases of the lung, liver, kidney, heart and vasculature. Recently, thrombin has been shown to promote fibroblast chemotaxis, proliferation and procollagen production in vitro and it has been proposed that it may contribute to tissue repair and fibrosis. Little is known about the cellular effects of the other coagulation cascade factors. The aim of this thesis is to study the effects of coagulation factors VIIa, IXa, Xa and fibrinogen cleavage products on fibroblast proliferation in vitro. This thesis shows that factor Xa is mitogenic for fibroblasts and the kinetics of this effect are equivalent to that of thrombin. Studies with specific inhibitors and antibodies demonstrated that this effect is dependent on its catalytic site, but independent of thrombin generation. Furthermore, this is mediated by platelet-derived growth factor production and autocrine stimulation similarly to thrombin. In contrast, factor IXa and fibrinogen-derived peptides have no effects, but factor VIIa and stimulates proliferation at high concentrations. Further studies of receptor expression, activation and intracellular calcium signalling showed that factor Xa stimulates proliferation via binding to effector cell-protease receptor-1 and the proteolytic activation of protease-activated receptor-1. In conclusion, this thesis demonstrated for the first time that coagulation cascade factors Xa and VIIa are mitogenic for fibroblasts, but not all peptides generated during blood coagulation. Furthermore, the mitogenic effect of factor Xa is mediated by a novel dual receptor system involving binding to effector-cell protease receptor-1 and activation of protease-activated receptor-1. These observations suggest that factor Xa may play a role in the regulation of fibroblast proliferation during normal tissue repair and fibrosis

Metric approximations of unrestricted wreath products when the acting group is amenable

We give a simple and unified proof showing that the unrestricted wreath product of a weakly sofic, sofic, linear sofic, or hyperlinear group by an amenable group is weakly sofic, sofic, linear sofic, or hyperlinear, respectively. By means of the Kaloujnine-Krasner theorem, this implies that group extensions with amenable quotients preserve the four aforementioned metric approximation properties. We also discuss the case of co-amenable groups.Fil: Brude, Javier Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Argentino de Matemática Alberto Calderón; ArgentinaFil: Sasyk, Roman. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Matemática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Argentino de Matemática Alberto Calderón; Argentin

Risk transfer, self-selection and ex post efficiency in public procurement

We use standard results from agency theory to assess the ex ante and ex post efficiency of the fixed price risk transfer contracts used to procure public infrastructure under the Private Finance Initiative (PFI) in the United Kingdom. We argue that these contracts act as a revelation mechanism designed to improve ex ante contracting efficiency at the cost of ex post inefficiency: PFI contract are a case of solving the moral hazard problem (creating maximum incentives for cost reduction) at the expense of increasing the adverse selection problem and therefore the selected firm’s information rent. Hence, Risk transfer leads to ex post inefficient outcomes that are directly related to the distribution of firm type: the more this distribution is skewed in favour of a few efficient firms, the less competition there is for the risk transfer contract, the larger the rent of the efficient firm should be. Thus, the ex post inefficiency of PFI contracts may be heavily country dependent. Using a detailed database of individual construction contracts for standard and PFI school projects in the UK, we find that full risk transfer does indeed lead to self-selection by the efficient firm, and that the distribution of firm types is indeed skewed in this market. We also find evidence of lower unit construction costs for the firm under PFI contracts compared to traditional procurement, which supports the hypothesis of the self-selection of the efficient firm when the public sector creates a menu of contracts (PFI vs. TP).Dans cet article nous nous reposons sur des résultats standards de la théorie de l’agence pour évaluer l’efficience ex ante et ex post des contrats à prix fixe effectivement utilisés pour certain marchés publics, en particulier dans le cadre du programme connu sous le nom de Private Finance Initiative (PFI) au Royaume-Uni. Ces contrats font office de mécanisme de révélation du type (efficient ou non) de l’agent et ont pour particularité de privilégier l’efficience contractuelle ex ante au détriment de l’efficience ex post : les contrats de type PFI résolvent la question du hasard moral (la création d’incitations maximales pour la réduction des coûts) au prix d’une maximisation du problème de la sélection adverse et donc de la rente informationnelle de la firme. L’inefficience ex post qui s’en suit est donc directement fonction de la distribution statistique du type de firme (efficiente/non-efficiente) dans l’économie : plus cette distribution favorise une petits groupes de firmes efficientes, moins il y a de concurrence pour le contrat, plus la rente informationnelle est importante. L’inefficience ex post des contrats de type PFI doit donc être en partie fonction de caractéristiques locales. Nous utilisons une base de données de coûts de construction unitaires dans le secteur des écoles primaires et secondaires au R.-U. et confirmons l’hypothèse d’une auto-sélection de la firme efficiente suite à l’utilisation de contrat de transfert de risque pour les marchés publics, ainsi que celle de la nature biaisée de la distribution du type de firme. Nous constatons également des coûts de construction unitaires plus bas dans les projets de type PFI que dans les autres marchés publics, ce qui tend aussi à confirmer que l’utilisation des contrats de type PFI en parallèle à ceux de maîtrise d’ouvrage créé un ‘menu’ de contrats (PFI vs. MOP) qui mène à l’auto-sélection de la firme efficiente

Aproximaciones en productos verbales de grupos y productos corona verbales de grupos, propiedades de permanencia y aplicaciones

El capítulo 1 de la tesis está destinado a dar una introducción a los temas a tratar y presentar los resultados demostrados a lo largo de la tesis. El capítulo 2 es una compilación de resultados preliminares. El capítulo 3 está destinado a demostrar resultados de permanencia en el producto corona irrestricto. El capítulo 4 está destinado a la definición de productos verbales y a demostrar propiedades de permanencia en él. El capítulo 5 está destinado a la definición de productos corona verbales y a demostrar propiedades de permanencia en él. Además se realizan aplicaciones de las construcciones elaboradas en la tesis.Facultad de Ciencias Exacta

Cooperation and opportunism under long-term public-private contracts: Evidence from water concessions in Asia.

This thesis addresses the implementation of long-term public-private contracts for utility services. Long-term contracts are inevitably incomplete and need to be adjusted over time to take account of new information or changes in the operating environment. Institutional environments, especially in developing countries, are also very likely to be incomplete. The existing literature has tended to focus on one of these two types of incompleteness; this thesis takes the analysis a step further by integrating the two into a single approach. Many contracts contain provisions for periodic adjustments to their terms, 'contractually mandated renegotiations.' Other adjustments will be necessary to rebalance a contract after a major shock, 'shock-induced renegotiations.' This research looks at both these types of adjustment in incomplete institutional environments and considers the behaviour of government and firm actors. The analysis proceeds in three steps. First, regression analysis of an original database of PSP projects, 'WATSUP', is used to test the relationship between institutions the number of PSP projects in each country. This confirms the significance of institutions. Second, a framework for the analysis of government and firm behaviour is developed which takes into account the two types of incompleteness, time inconsistency, actors' time preferences and the role of multiple actors. Third, in-depth case studies of the implementation of PSP contracts for water services in Manila and Jakarta are presented, based on more than 50 personal interviews in the two locations. The findings suggest that contractual incompleteness can be better managed if: the parties agree a set of principles and procedures for contract adjustment at the outset; set out clear lines of responsibility for contract renegotiation and approval; and establish contract-specific regulatory institutions with clearly defined implementation responsibilities