Desequilibri 234Th/238U per a l'estudi del cicle de partícules al Mediterrani nord-occidental

El desequilibri 238U/234Th s’utilitza per traçar el cicle de les partícules a la part més superficial dels oceans. Això és possible degut a les diferències entre els seus períodes de semidesintegració (T1/2 (234Th)=24,1 d; T1/2 (238U)=4,5 10 9 anys) i a les seves característiques biogeoquímiques: el Th presenta una gran afinitat per les partícules mentre que l’U és conservatiu en aigua de mar. En absència de partícules s’esperaria tenir equilibri secular entre ambdós radionúclids, però com que l’oceà no està lliure de partícules, el 234Th és exportat des de les capes més superficials produint-se un dèficit respecte el seu pare, l’238U. El període de semidesintegració del 234Th és molt adequat per traçar processos d’escales temporals de dies a setmanes, del mateix ordre que el desenvolupament de la floració del fitoplàncton i a la posterior exportació de partícules. En aquest treball es presenten dades obtingudes durant dues campanyes oceanogràfiques realitzades en el marc del Projecte FAMOSO (2009) en el Mediterrani nordoccidental, abans i després de la floració de fitoplàncton de primavera a la zona. Una de les peculiaritats d’aquesta regió és el procés de convecció profunda d’hivern, el qual suposa un important mecanisme de fertilització. A partir dels fluxos de 234Th obtinguts a la columna d’aigua es poden establir les pautes temporals que ha seguit el fitoplàncton en les setmanes prèvies al mostreig. Aquesta informació es compara amb els fluxos obtinguts utilitzant trampes de sediment a la deriva instal·lades durant ambdues campanyes.

Mixing invariants of hyperbolic 3-manifolds

Let M be a compact hyperbolic 3-manifold with incompressible boundary. Consider a complete hyperbolic metric on int(M). To each geometrically finite end of int(M) are traditionnaly associated 3 different invariants : the hyperbolic metric associated to the conformal structure at infinity, the hyperbolic metric on the boundary of the convex core and the bending measured lamination of the convex core. In this note we show how invariants of different types can be realised in the different ends.

Contribució de les varietats locals a la conservació de l'agrobiodiversitat: cas d'estudi en horts d'alta muntanya al Pallars Jussà, Pirineu català

Durant les últimes dècades, el paper dels horts familiars en la conservació de la agrobiodiversitat ha adquirit cada vegada més importància a nivell mundial. Les varietats locals que es cultiven en aquests horts tenen propietats intrínseques que les fan superiors a les comercials en molts aspectes, com han demostrat alguns dels estudis sobre aquests agroecosistemes duts a terme als Tròpics, i que posen en evidència l'actual sistema agrícola, alhora que representen una oportunitat per al desenvolupament sostenible de l´agricultura. En aquest treball d'investigació, dut a terme a la Vall Fosca (Pirineus Català d'Espanya) s'ha estudiat el paper les varietats locals dels horts familiars com a mecanisme de millora i manteniment d'aquests agroecosistemes, analitzant quins són els possibles factors sociodemogràfics i ecològics que condicionen el desenvolupament d'aquestes varietats als horts familiars.

Lactic acid bacteria from fresh fruit and vegetables as biocontrol agents of phytopathogenic bacteria and fungi

This study evaluated the efficacy of lactic acid bacteria (LAB) isolated from fresh fruits and vegetables as biocontrol agents against the phytopathogenic and spoilage bacteria and fungi, Xanthomonas campestris, Erwinia carotovora, Penicillium expansum, Monilinia laxa, and Botrytis cinerea. The antagonistic activity of 496 LAB strains was tested in vitro and all tested microorganisms except P. expansum were inhibited by at least one isolate. The 496 isolates were also analyzed for the inhibition of P. expansum infection in wounds of Golden Delicious apples. Four strains (TC97, AC318, TM319, and FF441) reduced the fungal rot diameter of the apples by 20%; only Weissella cibaria strain TM128 decreased infection levels by 50%. Cell-free supernatants of selected antagonistic bacteria were studied to determine the nature of the antimicrobial compounds produced. Organic acids were the preferred mediators of inhibition but hydrogen peroxide was also detected when strains BC48, TM128, PM141 and FF441 were tested against E. carotovora. While previous reports of antifungal activity by LAB are scarce, our results support the potential of LAB as biocontrol agents against postharvest rot. [Int Microbiol 2008; 11(4):231-236]

On the morphological nature of spanish adverbs ending in -mente

The morphological status of adverbs ending in -mente in Spanish (-ly in English) has been the object of many studies and continues to be the subject of debate. The two main proposals regarding the morphology of these adverbs treat them as either compounds or derivatives as the result of suffixation, but bothhypotheses present problems. In this study an analysis will be defended which treats -mente as a phrasal affix (cf. Zwicky 1987, Nevis 1985 and Miller 1992). The notion of phrasal affix has been used to describe clitics which, from a morphological standpoint, are similar to affixes but which, simultaneously manifest characteristics of independent words. The argument for analyzing -mente as a phrasal affix is based on both synchronic and diachronic data, including some similarities with object clitic pronouns.

Humour and translation, an interdiscipline

This paper calls for greater attention from researchers into the nature of humor translation as an interdisciplinary area that should be of interest to translation and humor studies. It includes a brief review of the complexity of translation and the problems posed by traditional approaches. The paper introduces a number of parameters that may be of assistance in developing joke typologies for translators or translation scholars. A model is presented for structuring joke-types according to binary branching. An attempt is then made to combine the model with ideas and concepts put forward in Attardo (2002). The result is a binary branch tree for the 6 Knowledge Resources and the hierarchical structure that Attardo claims they have. One important conclusion is that sameness, or similarity, may have little to do with funniness, and, if this is so, it is going to create a dilemma for translators wishing to achieve equivalent effect.

Correlation of the EPR properties of perchlorotriphenylmethyl radical and their efficiency as DNP polarizers

Water soluble perchlorinated trityl (PTM) radicals were found to be effective 95 GHz DNP (dynamic nuclear polarization) polarizers in ex situ (dissolution) 13C DNP (Gabellieri et al., Angew Chem., Int. Ed. 2010, 49, 3360). The degree of the nuclear polarization obtained was reported to be dependent on the position of the chlorine substituents on the trityl skeleton. In addition, on the basis of the DNP frequency sweeps it was suggested that the 13C NMR signal enhancement is mediated by the Cl nuclei. To understand the DNP mechanism of the PTM radicals we have explored the 95 GHz EPR characteristics of these radicals that are relevant to their performance as DNP polarizers. The EPR spectra of the radicals revealed axially symmetric g-tensors. A comparison of the spectra with the 13C DNP frequency sweeps showed that although the solid effect mechanism is operational the DNP frequency sweeps reveal some extra width suggesting that contributions from EPR forbidden transitions involving 35,37Cl nuclear flips are likely. This was substantiated experimentally by ELDOR (electron-electron double resonance) detected NMR measurements, which map the EPR forbidden transitions, and ELDOR experiments that follow the depolarization of the electron spin upon irradiation of the forbidden EPR transitions. DFT (density functional theory) calculations helped to assign the observed transitions and provided the relevant spin Hamiltonian parameters. These results show that the 35,37Cl hyperfine and nuclear quadrupolar interactions cause a considerable nuclear state mixing at 95 GHz thus facilitating the polarization of the Cl nuclei upon microwave irradiation. Overlap of Cl nuclear frequencies and the 13C Larmor frequency further facilitates the polarization of the 13C nuclei by spin diffusion. Calculation of the 13C DNP frequency sweep based on the Cl nuclear polarization showed that it does lead to an increase in the width of the spectra, improving the agreement with the experimental sweeps, thus supporting the existence of a new heteronuclear assisted DNP mechanism.

Gold or green: the debate on Open Access policies

The movement for open access to science seeks to achieve unrestricted and free access to academic publications on the Internet. To this end, two mechanisms have been established: the gold road, in which scientific journals are openly accessible, and the green road, in which publications are self-archived in repositories. The publication of the Finch Report in 2012, advocating exclusively the adoption of the gold road, generated a debate as to whether either of the two options should be prioritized. The recommendations of the Finch Report stirred controversy among academicians specialized in open access issues, who felt that the role played by repositories was not adequately considered and because the green road places the burden of publishing costs basically on authors. The Finch Report"s conclusions are compatible with the characteristics of science communication in the UK and they could surely also be applied to the (few) countries with a powerful publishing industry and substantial research funding. In Spain, both the current national legislation and the existing rules at universities largely advocate the green road. This is directly related to the structure of scientific communication in Spain, where many journals have little commercial significance, the system of charging a fee to authors has not been adopted, and there is a good repository infrastructure. As for open access policies, the performance of the scientific communication system in each country should be carefully analyzed to determine the most suitable open access strategy. [Int Microbiol 2013; 16(3):199-203]