Sustainability and competitiveness of the Inter-Oceanic Corridor of the Isthmus of Tehuantepec

The project entitled “Corredor Interoceánico del Istmo de Tehuantepec” (Tehuantepec Isthmus Interocean Corridor), aims to take advantage of Mexico's strategic geolocation to serve as another link for international business between Asia and the America East Coast. This is a Mexican government project focused on increasing Mexico’s competitiveness in international trade by reducing the transit time between vessels coming from Asia to the United States East Coast and vice versa. The project explores connecting the Pacific Ocean with the Gulf of Mexico, through the Tehuantepec Isthmus, using the current railway infrastructure that links the ports of Coatzacoalcos (Veracruz state) and Salina Cruz (Oaxaca state). This paper analyzes the sustainability and competitiveness of the project in terms of its economic, social and environmental impact. Variables (time and cost) will be compared against other major commercial links, such as the Panama Canal (ports of Balboa to Colón), and various ports on the east and west side of the United States. This proposal considers the logistics and capacities/limitations of both maritime and land transportation, since it would connect both Mexican ports with other ports from the United States or other countries bordering Mexico. However, this research paper does not take into consideration the costs or initial investment and capacities of infrastructure for the remodeling of the railways and the ports, or any other investments that may be required to carry out the project

Measuring Urban Agglomeration: A Refoundation of the Mean City-Population Size Index

La relevancia de las economías de aglomeración tipo urbanización sobre múltiples variables y/o dinámicas económicas se encuentra ampliamente documentada en la literatura. Sin embargo, es difícil ofrecer una medida sintética del nivel de aglomeración urbana que alcanza un territorio. En este trabajo se propone un índice de aglomeración que cumple tres propiedades fundamentales: i) aumentar en función de la concentración de la población y cumplir el principio de transferencia de Pigou-Daltonii) aumentar con el tamaño absoluto del territorio donde se producen interacciones de la población, y iii) ser consistente en la agregación. Se desarrolla un índice de aglomeración en función del número de oportunidades de interacción por habitante en un área geográfica, que considera las interacciones de pares y la delineación espacial de mercados de trabajo locales (LLMA, por sus siglas en inglés). La medida es la esperanza matemática del tamaño del LLMA donde vive un individuo aleatorio y se asemeja a la propuesta de Arriaga (1970, 1975). Adicionalmente, el índice posee varias características importantes. No requiere un umbral de población arbitraria para separar urbano de no urbano. Se puede adaptar a los casos en los que un LLMA radica en parte fuera de la zona geográfica para la que se mide la aglomeración. Finalmente, se puede aproximar de forma adecuada cuando hay datos truncados o con una elevada agregación. Para evaluar el funcionamiento del índice, se examina su correlación con los coeficientes de localización de las actividades de servicios a empresas intensivos en conocimiento, de las provincias españolas. Las correlaciones son claramente más elevadas que las obtenidas con el índice clásico de urbanización o el índice de concentración de Hirschman-HerfindahlIn this paper, we put forth the view that the potential for urbanisation economies increases with interaction opportunities. On the basis of that premise, three properties are key to an agglomeration index, which should: (i) increase with the concentration of population and conform to the Pigou-Dalton transfer principle(ii) increase with the absolute size of constituent population interaction zonesand (iii) be consistent in aggregation. Confining our attention to pairwise interactions, and invoking the space-analytic foundations of local labour market area (LLMA) delineation, we develop an index of agglomeration based on the number of interaction opportunities per capita in a geographical area. This leads to Arriaga’s mean city-population size, which is the mathematical expectation of the size of the LLMA in which a randomly chosen individual lives. The index has other important properties. It does not require an arbitrary population threshold to separate urban from non-urban areas. It adapts readily to situations where an LLMA lies partly outside the geographical area for which agglomeration is measured. Finally, it can be satisfactorily approximated when data are truncated or aggregated into size classes. We apply the index to the Spanish NUTS III regions, and evaluate its performance by examining its correlation with the location quotients of several knowledge-intensive business services (KIBS) known to be highly sensitive to urbanisation economies. The Arriaga index correlations are clearly stronger than those of either the classical degree of urbanisation or the Hirshman-Herfindahl concentration inde

Outcomes in Newly Diagnosed Atrial Fibrillation and History of Acute Coronary Syndromes: Insights from GARFIELD-AF

BACKGROUND: Many patients with atrial fibrillation have concomitant coronary artery disease with or without acute coronary syndromes and are in need of additional antithrombotic therapy. There are few data on the long-term clinical outcome of atrial fibrillation patients with a history of acute coronary syndrome. This is a 2-year study of atrial fibrillation patients with or without a history of acute coronary syndromes