Desenvolupament de mesures per comparar transculturalment xarxes personals (USA i Estats Units)

Estudi elaborat a partir d’una estada a la Universitat de Florida durant Abril i Maig de 2006. “Application to Immigrant Populations in South Florida and Northeastern Spain" ha permès recollir les xarxes personals d’immigrants en els dos països mitjançant un qüestionari implementat amb un software desenvolupat ex professo per recollir i presentar visualment les dades. Es van revisar i assemblar les entrevistes i qüestionaris realitzats a Catalunya i a Estats Units (Miami i Nova York, especialment). Fins al moment s’han revisat i analitzat uns 450 casos. Un cop depurada i analitzada la informació obtinguda s’ha pogut disposar per primer cop de mesures globals pels diferents col•lectius estudiats. L'objectiu global del projecte és entendre les implicacions que les estructures de les xarxes personals tenen en relació a un conjunt de conductes (de salut, d'ús de la llengua, etx) i les autoconcepcions. En aquest sentit era necessari desenvolupar un seguit de mesures que permetessin comparar i documentar la variació de les estructures de les xarxes personals a diferents cultures, nivells socioeconòmics, gènere, religió, etc. i incorporar-les com a variables independents als models explicatius.En aquest moments s’està desenvolupant un índex basat en variables estructurals (número de components de la xarxa, densitat, grau d’intermediació, etc.) i variables de composició (proporció de persones diferents del país d’origen, entre d'altres). La idea és disposar d’un índex d’heterogeneïtat de la xarxa social comparable entre els diferents col•lectius. Malgrat que el treball continua, la principal conclusió a la que s’ha arribat és que al menys a Espanya a mida que passa el temps augmenta el nivell d’heterogeneïtat de les xarxes personals. És a dir, que desprès d’un ràpid procés de canvi i una fase de transnacionalitat la tendència és a reduir aquest nivell (pels costos socials i econòmics que comporta) depenent, naturalment, de factors com l’origen temporal (primera onada o successives), el tipus de col•lectiu i el sexe.

Desenvolupament de dipòsits institucionals als Estats Units a partir de l'inici del 2005

Aquest article analitza la situació dels dipòsits institucionals als EUA mitjançant una enquesta realitzada per la CNI a les seves institucions acadèmiques. Amb aquesta enquesta s'obtingué informació sobre el grau d'implementació dels dipòsits i la seva extensió, així com del tipus de materials. A més, va servir per conèixer l'opinió de les institucions sobre els dipòsits, i va quedar palès que la major part de les que no en posseeixen, tenen previst posar-ne un en funcionament, tot i que els preocupi el cost de manteniment. L'article també tracta la responsabilitat administrativa dels dipòsits, les polítiques que els gestionen, la possibilitat de compartir dipòsits entre institucions i la procedència dels materials que contenen.

Uranium reserve, nuclear fuel cycle delusion, CO2 emission from the sea, and electricity supply: reflections after the fuel meltdown of Fukushima nuclear power units

The Great Tohoku-Kanto earthquake and resulting tsunami has brought considerable attention to the issue of the construction of new power plants. We argue in this paper, nuclear power is not a sustainable solution to energy problems. First, we explore the stock of uranium-235 and the different schemes developed by the nuclear power industry to exploit this resource. Second, we show that these methods, fast breeder and MOX fuel reactors, are not feasible. Third, we show that the argument that nuclear energy can be used to reduce CO2 emissions is false: the emissions from the increased water evaporation from nuclear power generation must be accounted for. In the case of Japan, water from nuclear power plants is drained into the surrounding sea, raising the water temperature which has an adverse affect on the immediate ecosystem, as well as increasing CO2 emissions from increased water evaporation from the sea. Next, a short exercise is used to show that nuclear power is not even needed to meet consumer demand in Japan. Such an exercise should be performed for any country considering the construction of additional nuclear power plants. Lastly, the paper is concluded with a discussion of the implications of our findings.

Estudi descriptiu de l'ús de xarxes socials online per la promoció de l'alimentació saludable en hospitals dels Estats Units

Internet i les xarxes socials online s'estan mostrant com a útils en la promoció de la salut i en la difusió d'hàbits saludables. L'objectiu del treball és observar el grau d'utilització que es fa de les xarxes socials online per a la promoció d'hàbits d'alimentació saludable. S'ha dissenyat un estudi observacional descriptiu transversal amb una mostra de 14 hospitals dels Estats Units. A l'estudi s'ha trobat una bona freqüència d'utilització dels canals que ofereix la xarxa però una baixa freqüència per fer promoció d'hàbits saludables en alimentació.

Fronts from two-dimensional dispersal kernels: Beyond the nonoverlapping-generations model

Most integrodifference models of biological invasions are based on the nonoverlapping-generations approximation. However, the effect of multiple reproduction events overlapping generations on the front speed can be very important especially for species with a long life spam . Only in one-dimensional space has this approximation been relaxed previously, although almost all biological invasions take place in two dimensions. Here we present a model that takes into account the overlapping generations effect or, more generally, the stage structure of the population , and we analyze the main differences with the corresponding nonoverlappinggenerations results

Fronts from complex two-dimensional dispersal kernels: theory and application to Reid's paradox

Bimodal dispersal probability distributions with characteristic distances differing by several orders of magnitude have been derived and favorably compared to observations by Nathan [Nature (London) 418, 409 (2002)]. For such bimodal kernels, we show that two-dimensional molecular dynamics computer simulations are unable to yield accurate front speeds. Analytically, the usual continuous-space random walks (CSRWs) are applied to two dimensions. We also introduce discrete-space random walks and use them to check the CSRW results (because of the inefficiency of the numerical simulations). The physical results reported are shown to predict front speeds high enough to possibly explain Reid's paradox of rapid tree migration. We also show that, for a time-ordered evolution equation, fronts are always slower in two dimensions than in one dimension and that this difference is important both for unimodal and for bimodal kernels

La Utilització d'internet en les campanyes electorals als Estats Units i a Espanya : comparació de la campanya de Barack Obama (2008) i dels principals candidats de l'Estat (2011)

La campanya electoral de Barack Obama per guanyar les eleccions nord-americanes l'any 2008 s'ha convertit en el referent de les e-campanyes. En aquesta investigació es fa una anàlisi de l'estratègia que va plantejar el candidat demòcrata a internet enfront les que van plantejar els principls candidats a les Eleccions Generals espanyoles el 2011: Mariano Rajoy (PP), Alfredo Pérez Rubalcaba (PSOE) i Josep Antoni Duran i Lleida (CiU). La investigació es planteja des de l'àmbit de la comunicació política a través d'una perspectiva comparativa i pren, fonamentalment, caràcter qualitatiu.

Accelerated tumor invasion under non-isotropic cell dispersal in glioblastomas

Glioblastomas are highly diffuse, malignant tumors that have so far evaded clinical treatment. The strongly invasive behavior of cells in these tumors makes them very resistant to treatment, and for this reason both experimental and theoretical efforts have been directed toward understanding the spatiotemporal pattern of tumor spreading. Although usual models assume a standard diffusion behavior, recent experiments with cell cultures indicate that cells tend to move in directions close to that of glioblastoma invasion, thus indicating that a biasedrandom walk model may be much more appropriate. Here we show analytically that, for realistic parameter values, the speeds predicted by biased dispersal are consistent with experimentally measured data. We also find that models beyond reaction–diffusion–advection equations are necessary to capture this substantial effect of biased dispersal on glioblastoma spread

Dispersal probability distributions and the wave-front speed problem

The speed and width of front solutions to reaction-dispersal models are analyzed both analytically and numerically. We perform our analysis for Laplace and Gaussian distribution kernels, both for delayed and nondelayed models. The results are discussed in terms of the characteristic parameters of the models

Aportacions per a una bibliografia de l'exili republicà català, valencià i balear als Estats Units d'Amèrica

This article attempts to gather together the work published in the United States and Puerto Rico by Spanish Civil War exiles of Catalan, Valencia and Balearic origin. Included are books, serials, sheet music, sound recordings and domestic movie videos, which have appeared in US territory from 1936 through 2004. The objective of the bibliography is to provide both an overview and a starting point for recovering the intellectual effort carried out by these exiles because this first inventory must still be completed with the addition of journal articles, contributions to monographs, and conference proceedings. There have also been exiles for whom books, music or videos have not been found, but for whom a certain level of intellectual activity is known or suspected. Such potential work would include articles and other contributions to journals in the US or cultural and membership activities of Catalan communities in that country. Without being able to offer definitive conclusions, it appears that exile in North America was a solitary experience, and never as a cohesive group or with the ties of mutual interests as was the case in Mexico or even in France. There were neither readers nor publishers to facilitate publication and to serve for creating group cohesiveness.

Design of homogeneous territorial units : a methodological proposal

One of the main questions to solve when analysing geographically added information consists of the design of territorial units adjusted to the objectives of the study. This is related with the reduction of the effects of the Modificable Areal Unit Problem (MAUP). In this paper an optimisation model to solve regionalisation problems is proposed. This model seeks to reduce disadvantages found in previous works about automated regionalisation tools

Design of homogeneous territorial units : a methodological proposal

One of the main questions to solve when analysing geographically added information consists of the design of territorial units adjusted to the objectives of the study. This is related with the reduction of the effects of the Modificable Areal Unit Problem (MAUP). In this paper an optimisation model to solve regionalisation problems is proposed. This model seeks to reduce disadvantages found in previous works about automated regionalisation tools

Marine and transitional Middle/Upper Eocenen units of the Southeastern Pyrenean Foreland Basin (NE Spain)

The stratigraphic basis of this work has allowed the use of larger foraminifers in the biostratigraphic characterisation of the new Shallow Benthic Zones (SBZ). This part of the volume presents a description of the sedimentary cycles formed by the transgressive-regressive systems of the Lutetian and Bartonian in the southeastern sector of the Ebro Foreland Basin. Concerning the Lutetian deposits studied in the Amer-Vic and Empordà areas, four sedimentary cycles have been characterised. The first and second are found within the Tavertet/Girona Limestone Formation (Reguant, 1967; Pallí, 1972), while the third and fourth cycles cover the Coll de Malla Marl Formation (Clavell et al., 1970), the Bracons Formation (Gich, 1969, 1972), the Banyoles Marl Formation (Almela and Ríos, 1943), and the Bellmunt Formation (Gich, 1969, 1972). In the Bartonian deposits studied in the Igualada area, two transgressive-regressive sedimentary cycles have been characterised in the Collbàs Formation (Ferrer, 1971), the Igualada Formation (Ferrer, 1971), and the Tossa Formation (Ferrer, 1971). The Shallow Benthic Zones (SBZs) recognised within the Lutetian are the following: SBZ 13, from the Early Lutetian, in the transgressive system of the first cycle; SBZ 14, from the Middle Lutetian, in the second cycle and the lower part of the transgressive system of the third cycle; SBZ 15, from the Middle Lutetian, in the remaining parts of the third system; SBZ 16, from the Late Lutetian, throughout the fourth cycle. The association of larger foraminifers in the first and second cycles of the Bartonian in the Igualada area has been used as the basis for the definition of SBZs 17 and 18 recognised in the Bartonian of the western Tethys.