Material Flow Accounting in Chile, Ecuador, Mexico and Peru (1980-2000)

In this paper we compare the resource flows of Chile, Ecuador, Mexico and Peru between 1980 and 2000. In this time span, the domestic extraction of materials increased in the four countries, mainly due to the mining sector in Chile and Peru, biomass and oil in Ecuador and construction minerals in Mexico. Imports and exports increased too, due to the increasing integration in the international markets, prompted by the liberalization policies undertaken by the four countries between the late 1970s and the late 1990s. The four countries had a negative physical trade balance for most of the period analyzed, meaning that their exports exceeded their imports in terms of weight. However, the increase of imports reduced the physical deficit in Chile, Mexico and Peru. Ecuador’s physical deficit was the highest and did not decrease in the period analyzed. Also, a diversification of exports away from bulk commodities could be observed in Chile and Mexico, and to a lesser extent in Peru, whereas in Ecuador the export sector remained mainly based on oil and biomass. More research is needed to explore the environmental effects of this phenomenon. Also, the indirect flows associated to the direct physical flows deserve to be subject to further analysis.

Role of fluid mixing in deep dissolution of carbonates

The presence of cavities filled with new minerals in carbonate rocks is a common feature in oil reservoirs and lead-zinc deposits. Since groundwater equilibrates rapidly with carbonates, the presence of dissolution cavities in deep carbonate host rocks is a paradox. Two alternative geochemical processes have been proposed to dissolve carbonates at depth: hydrogen sulfide oxidation to sulfuric acid, and metal sulfide precipitation. With the aid of geochemical modeling we show that mixing two warm solutions saturated with carbonate results in a new solution that dissolves limestone. Variations in the proportion of the end-member fluids can also form a supersaturated mixture and fill the cavity with a new generation of carbonate. Mixing is in general more effective in dissolving carbonates than the aforementioned processes. Moreover, mixing is consistent with the wide set of textures and mineral proportions observed in cavity infillings.

Preparació, estudi estructural i aplicabilitat de derivats de Poli-(4R)-hidroxi-L-prolina a la separació d’enantiòmers per tècniques cromatogràfiques o relacionades

La separació d’enantiòmers (isòmers òptics) és molt important en molts diversos camps, com les síntesis quirals, biologia, i en el camp de la farmacologia especialment. És per això, que es fa necessari de disposar de tècniques i mètodes analítics ràpids, fiables i sensibles per a la separació d’enantiòmers. La present tesi s’emmarca en el camp de la separació d’enantiòmers, concretament en la preparació de fases estacionàries quirals per al seu ús en cromatografia liquida. En aquest sentit, s’ha desenvolupat la síntesi i caracterització de molècules polimèriques quirals derivades de l’aminoàcid L-prolina que incorporades en matrius de gel de sílice poden constituïr columnes quirals per a la separació d’enantiòmers per cromatografia liquida. S’han estudiat les característiques enantioselectives d’aquests nous materials en la separació de molècules quirals, trobant-se ésser satisfactòriament enantioselectius. L’interès que suscita l’obtenció d’enantiòmers a gran escala fa que la recerca s’orienti a la recerca de materials amb elevada capacitat de càrrega, és a dir, que puguin donar lloc a la separació d’elevades quantitats d’enantiòmers. Amb aquesta finalitat s’han dut a terme assaigs de capacitat de càrrega, que han posat de manifest la possible aplicació d’aquests materials a la separació preparativa d’enantiòmers. També s’ha parat especial atenció a l’estudi de les característiques de la matriu de gel de sílice, assajant-se altres materials de sílice més porosos i que permeten així treballar amb fluxos més elevats tot reduint-ne el temps d’anàlisi i els costos associats a la separació preparativa d’enantiòmers. L'estudi conformacional d'aquests nous selectors també ha estat contemplat per tal d'explicar l'enantioselectivitat específica que s'observa en certs dissolvents orgànics en els qual es duu a terme la separació dels enantiòmers.

Addressing the natural resource curse: An illustration from Nigeria

Some natural resources oil and minerals in particular exert a negative andnonlinear impact on growth via their deleterious impact on institutionalquality. We show this result to be very robust. The Nigerian experienceprovides telling confirmation of this aspect of natural resources. Wasteand corruption from oil rather than Dutch disease has been responsible forits poor long run economic performance. We propose a solution for addressingthis resource curse which involves directly distributing the oil revenuesto the public. Even with all the difficulties of corruption and inefficiencythat will no doubt plague its actual implementation, our proposal will, atthe least, be vastly superior to the status quo. At best, however, it couldfundamentally improve the quality of public institutions and, as a result,transform economics and politics in Nigeria.

Farmacología y toxicología en I+D+i: adquisición de competencias a través de un ejemplo de desarrollo de un fármaco

The implementation of the subject Pharmacology and Toxicology in R+D+i in the Pharmacy Degree, has led to the launch of a new methodological approach and teaching performance with the aim of developing the generic skills of the University of Barcelona (e.g., self-learning, team-working). An additional objective was students' integration of knowledge from different subjects in the degree which form the basis of the preclinical and clinical development of a drug. For this purpose, the teaching strategy used in the development of the subject was based on: 1) re-developing the content that students had been taught previously or were being taught in the same semester as a part of other subjects, and framing them in the environment of the pharmaceutical industry, 2) introducing new and previously unseen contents to do with drug development and toxicology, 3) developing a battery of activities to be undertaken by teams of students relating to the R+D+i of a particular drug. During the development of these activities, students have to acquire generic skills in addition to the subject-specific skills. The results obtained from the student survey give us grounds for satisfaction and allow us to consider that we have reached the goal of improving students' learning in Pharmacology and Toxicology applied to drug development in the pharmaceutical world today.

Nivel de mercurio en cabello de ninos peruanos expuestos en una zona minera de Arequipa y de la ciudad de Lima

Objetivo: El propósito del estudio fue comparar los niveles de mercurio en cabello en dos muestras de ninos peruanos provenientes de dos zonas geográficas distintas: una zona rural minera y una zona urbana. Material y métodos: La zona minera correspondió al poblado de Mollehuaca (Arequipa), de donde se obtuvieron 52 muestras de cabello; la zona urbana no expuesta a minería correspondió al distrito de Los Olivos (Lima), de donde se obtuvieron 40 muestras. Se determinó el nivel de mercurio con la técnica estandarizada de plasma de inducción acoplado con un espectrómetro de masas (ICP-MS). Resultados: En la zona rural, en promedio, se obtuvo un nivel de mercurio de 7,47 ppb±26,9. En la zona urbana, el nivel de mercurio alcanzó un promedio de 2,47 ppb±1,28. No se encontraron diferencias significatives en el nivel de mercurio según edad o género. Conclusión: Se concluye que el grupo expuesto a minería aurífera informal y de zona rural presentó niveles de mercurio en cabello en promedio mayores a los del grupo de zona urbana, pero esta diferencia no fue significativa (p=0,188, α=0,05).