The Rise of democracy in Europe and the fight against mass poverty in Latin America: the implications for marxist thought of some recent mainstream papers

Recently a number of mainstream papers have treated the rise of democracy in 19th century Europe and its instability in Latin America in an eminently Marxist fashion. This paper sets out their implications for Marxist thought. With respect to Europe, Marx's emphasis on political action backed by the threat of violence is vindicated but his justification for socialism is not. With respect to Latin America, the unequal distribution of wealth is the cause of political instability that is, in turn, the root cause of mass poverty. In addition it is possible to explain some of the paradoxical characteristics of neo-liberalism and to make a weak argument for socialism in spite of its rejection in Europe.

Convergence of the mass-transport steepest descent scheme for the sub-critical Patlak-Keller-Segel model

Variational steepest descent approximation schemes for the modified Patlak-Keller-Segel equation with a logarithmic interaction kernel in any dimension are considered. We prove the convergence of the suitably interpolated in time implicit Euler scheme, defined in terms of the Euclidean Wasserstein distance, associated to this equation for sub-critical masses. As a consequence, we recover the recent result about the global in time existence of weak-solutions to the modified Patlak-Keller-Segel equation for the logarithmic interaction kernel in any dimension in the sub-critical case. Moreover, we show how this method performs numerically in one dimension. In this particular case, this numerical scheme corresponds to a standard implicit Euler method for the pseudo-inverse of the cumulative distribution function. We demonstrate its capabilities to reproduce easily without the need of mesh-refinement the blow-up of solutions for super-critical masses.

Enabling dCache to use preexistent mass storage systems

A mesura que la investigació depèn cada vegada més dels computadors, l'emmagatzematge de dades comença a convertir-se en un recurs escàs per als projectes, i suposa una gran part del cost total. Alguns projectes intenten resoldre aquest problema emprant emmagatzament distribuït. És doncs necessari que alguns centres proveeixin de grans quantitats d'emmagatzematge massiu de baix cost basat en cintes magnètiques. L'inconvenient d'aquesta solució és que el rendiment disminueix, particularment a l'hora de tractar-se de grans quantitats d'arxius petits. El nostre objectiu és crear un híbrid entre un sistema d'alt cost i rendiment basat en discs, i un de baix cost i rendiment basat en cintes. Per això, unirem dCache, un sistema d'emmagatzematge distribuït, amb Castor, un sistema d'emmagatzematge jeràrquic, creant sistemes de fitxers virtuals que contindran grans quantitats d'arxius petits per millorar el rendiment global del sistema.

Critical mass for a Patlak-Keller-Segel model with degenerate diffusion in higher dimensions

"Vegeu el resum a l'inici del document del fitxer adjunt."

The new role of the mass media in the construction of sport and Olympic values

This paper was presented in the International Symposium on Toward the Creation of New-Sport Cultures, undertaken in Osaka, Japan, in January 28, 1996. The main purpose is to make an interpretation of the cultural values of sport and Olympism in contemporary society, considering the enormous influence that the media have on them.

Regularity and mass conservation for discrete coagulation-fragmentation equations with diffusion

We present a new a-priori estimate for discrete coagulation fragmentation systems with size-dependent diffusion within a bounded, regular domain confined by homogeneous Neumann boundary conditions. Following from a duality argument, this a-priori estimate provides a global L2 bound on the mass density and was previously used, for instance, in the context of reaction-diffusion equations. In this paper we demonstrate two lines of applications for such an estimate: On the one hand, it enables to simplify parts of the known existence theory and allows to show existence of solutions for generalised models involving collision-induced, quadratic fragmentation terms for which the previous existence theory seems difficult to apply. On the other hand and most prominently, it proves mass conservation (and thus the absence of gelation) for almost all the coagulation coefficients for which mass conservation is known to hold true in the space homogeneous case.

Strategic mass killings

Since World War II there have been about fifty episodes of large-scale mass killings of civilians and massive forced displacements. They were usually meticulously planned and independent of military goals. We provide a model where conflict onset, conflict intensity and the decision to commit mass killings are all endogenous, with two main goals: (1) to identify the key variables and situations that make mass killings more likely to occur; and (2) to distinguish conditions under which mass killings and military conflict intensity reinforce each other from situations where they are substitute modes of strategic violence. We predict that mass killings are most likely in societies with large natural resources, significant proportionality constraints for rent sharing, low productivity and low state capacity. Further, massacres are more likely in a civil than in an interstate war, as in the latter group sizes matter less for future rents. In non polarized societies there are asymmetric equilibria with only the larger group wanting to engage in massacres. In such settings the smaller group compensates for this by fighting harder in the first place. In this case we can talk of mass killings and fighting efforts to be substitutes. In contrast, in polarized societies either both or none of the groups can be ready to do mass killings in case of victory. Under the "shadow of mass killings" groups fight harder. Hence, in this case massacres and fighting are complements. We also present novel empirical results on the role of natural resources in mass killings and on what kinds of ethnic groups are most likely to be victimized in massacres and forced resettlements, using group level panel data.

Regional value added in Italy over the long run (1891-2001): linking indirect estimates with official figures, and implications

This paper presents value added estimates for the Italian regions, in benchmark years from 1891 until 1951, which are linked to those from official figures available from 1971 in order to offer a long-term picture. Sources and methodology are documented and discussed, whilst regional activity rates and productivity are also presented and compared. Thus some questions are briefly reconsidered: the origins and extent of the north-south divide, the role of migration and regional policy in shaping the pattern of regional inequality, the importance of social capital, and the positioning of Italy in the international debate on regional convergence, where it stands out for the long run persistence of its disparities.

Compositional evolution with mass transfer in closed systems

Evolution of compositions in time, space, temperature or other covariates is frequentin practice. For instance, the radioactive decomposition of a sample changes its composition with time. Some of the involved isotopes decompose into other isotopes of thesample, thus producing a transfer of mass from some components to other ones, butpreserving the total mass present in the system. This evolution is traditionally modelledas a system of ordinary di erential equations of the mass of each component. However,this kind of evolution can be decomposed into a compositional change, expressed interms of simplicial derivatives, and a mass evolution (constant in this example). A rst result is that the simplicial system of di erential equations is non-linear, despiteof some subcompositions behaving linearly.The goal is to study the characteristics of such simplicial systems of di erential equa-tions such as linearity and stability. This is performed extracting the compositional differential equations from the mass equations. Then, simplicial derivatives are expressedin coordinates of the simplex, thus reducing the problem to the standard theory ofsystems of di erential equations, including stability. The characterisation of stabilityof these non-linear systems relays on the linearisation of the system of di erential equations at the stationary point, if any. The eigenvelues of the linearised matrix and theassociated behaviour of the orbits are the main tools. For a three component system,these orbits can be plotted both in coordinates of the simplex or in a ternary diagram.A characterisation of processes with transfer of mass in closed systems in terms of stability is thus concluded. Two examples are presented for illustration, one of them is aradioactive decay

Estimating Gross Value Added (GVA) across multiple scales: theoretical approach and empirical validation

This paper presents an application of the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) approach to the estimation of quantities of Gross Value Added (GVA) referring to economic entities defined at different scales of study. The method first estimates benchmark values of the pace of GVA generation per hour of labour across economic sectors. These values are estimated as intensive variables –e.g. €/hour– by dividing the various sectorial GVA of the country (expressed in € per year) by the hours of paid work in that same sector per year. This assessment is obtained using data referring to national statistics (top down information referring to the national level). Then, the approach uses bottom-up information (the number of hours of paid work in the various economic sectors of an economic entity –e.g. a city or a province– operating within the country) to estimate the amount of GVA produced by that entity. This estimate is obtained by multiplying the number of hours of work in each sector in the economic entity by the benchmark value of GVA generation per hour of work of that particular sector (national average). This method is applied and tested on two different socio-economic systems: (i) Catalonia (considered level n) and Barcelona (considered level n-1); and (ii) the region of Lima (considered level n) and Lima Metropolitan Area (considered level n-1). In both cases, the GVA per year of the local economic entity –Barcelona and Lima Metropolitan Area – is estimated and the resulting value is compared with GVA data provided by statistical offices. The empirical analysis seems to validate the approach, even though the case of Lima Metropolitan Area indicates a need for additional care when dealing with the estimate of GVA in primary sectors (agriculture and mining).

The implementation of liquid chromatography tandem mass spectrometry for the official control of lipophilic toxins in seafood: Single-laboratory validation under four chromatographic conditions

We performed a comprehensive study to assess the fit for purpose of four chromatographic conditions for the determination of six groups of marine lipophilic toxins (okadaic acid and dinophysistoxins, pectenotoxins, azaspiracids, yessotoxins, gymnodimine and spirolides) by LC-MS/MS to select the most suitable conditions as stated by the European Union Reference Laboratory for Marine Biotoxins (EURLMB). For every case, the elution gradient has been optimized to achieve a total run-time cycle of 12 min. We performed a single-laboratory validation for the analysis of three relevant matrices for the seafood aquaculture industry (mussels, pacific oysters and clams), and for sea urchins for which no data about lipophilic toxins have been reported before. Moreover, we have compared the method performance under alkaline conditions using two quantification strategies: the external standard calibration (EXS) and the matrix-matched standard calibration (MMS). Alkaline conditions were the only scenario that allowed detection windows with polarity switching in a 3200 QTrap mass spectrometer, thus the analysis of all toxins can be accomplished in a single run, increasing sample throughput. The limits of quantification under alkaline conditions met the validation requirements established by the EURLMB for all toxins and matrices, while the remaining conditions failed in some cases. The accuracy of the method and the matrix effects where generally dependent on the mobile phases and the seafood species. The MMS had a moderate positive impact on method accuracy for crude extracts, but it showed poor trueness for seafood species other than mussels when analyzing hydrolyzed extracts. Alkaline conditions with EXS and recovery correction for OA were selected as the most proper conditions in the context of our laboratory. This comparative study can help other laboratories to choose the best conditions for the implementation of LC-MS/MS according to their own necessities.

Esfingolipids i senyal•lització cel.lular: l'(E)-2-hexadecenal com a possible lípid bioactiu

L’esfingosina-1-fosfat (S1P) és un lípid bioactiu amb funcions crucials en la biologia cel•lular. Entre aquestes, la seva activitat mitogènica i citoprotectora són les més estudiades. L’S1P és catabolitzada intracel•lularment mitjançant l’esfingosina-1-fosfat liasa (SGPL1) per generar (E)-2-hexadecenal i fosforiletanolamina. L’objectiu d’aquest projecte és explorar si l’(E)-2-hexadecenal és realment un catabòlit innocu o bé si, pel seu caràcter acceptor de Michael, és capaç de reaccionar amb pèptids o proteïnes específics. Aquesta interacció podria traduïr-se en funcions biològiques determinades, algunes de les quals són possiblement atribuïdes a l’esfingosina-1-fosfat com a tal. Per poder explorar el potencials adductes proteïcs amb l’aldehid, s’han emprat, sobre cèl•lules HeLa que sobreexpressen SGPL1, sondes anàlegs a esfingosina i esfinganina (i els seus derivats fosforil•lats) que presenten una funció azida en la posició omega de la cadena esfingoide. Aquestes, mitjançant química click sense coure, s’han fet reaccionar amb una molècula que presenta un dibenzociclooctí unit a biotina DBCObiotina). Després d’aïllar les proteïnes així biotinilades amb una reïna d’estreptavidina, aquestes es van separar per electroforesi. Les bandes proteïques observades es van extreure del gel i es van digerir amb tripsina, per posteriorment analitzar els pèptids per MALDI-TOF, el que permetria l’identificació de proteïnes a partir de “peptide mass fingerprinting”. Lamentablement, a la fi d’aquest contracte, encara no s’ha pogut identificar cap proteïna que s’uneixi a l’aldehid alliberat per la reacció de l’esfingosina-1- fosfat liasa. No obstant, durant aquest temps s’ha millorat el mètode per detectar aquests adductes proteïcs. Per això, si la recerca continua en aquesta línia, properament es podria saber amb certesa si existeixen o no aquestes interaccions covalents entre determinades proteïnes i l’(E)-2-hexadecenal.