Expansión de Lysiphlebus testaceipes (Cresson) (Hym., Braconidae, Aphidiinae) en el Noreste de la Península Ibérica

Lysyphlebus testaceipes (Cresson), un parasitoide exótico de pulgones establecido en la costa mediterránea, se ha encontrado regularmente en Lleida y en los Pirineos parasitando varias especies de pulgones, lo que demuestra su expansión desde las zonas costeras hacia el interior y zonas de montaña. Las especies de pulgón Aphis ruborum Börner, específica de Rubus sp., Aphis fabae Scopoli, polífaga, Brachycaudus cardui L., típica de cardos y Aphis urticata J.F. Gmelin, específica de Urtica sp., fueron hospedantes comunes de L. testaceipes en las zonas de estudio. La existencia de biocorredores transzonales, junto con el rango oligófago de hospedantes de L. testaceipes y su capacidad de alternar entre las especies de pulgones disponibles ha contribuido a la positiva expansión del parasitoide hacia zonas interiores o de montaña.

Sobre algunas plantas aloctonas

Los comentarios que siguen tienen su origen en una nota que redactamos en 1966 y que en principio debía haberse publicado en breve plazo la cual comprendía algunas consideraciones sobre Picea abies, Abutilón teophrasti, Impatiens balfourii, Citrullus colocynthis, Lonicera japónica y, particularmente, sobre Bidens áurea, especie de origen americano que descubrimos en Barcelona en 1963 y acerca de la cual M. CALDUCH dio noticia en 1973.

Renewal equations for option pricing

In this paper we will develop a methodology for obtaining pricing expressions for financial instruments whose underlying asset can be described through a simple continuous-time random walk (CTRW) market model. Our approach is very natural to the issue because it is based in the use of renewal equations, and therefore it enhances the potential use of CTRW techniques in finance. We solve these equations for typical contract specifications, in a particular but exemplifying case. We also show how a formal general solution can be found for more exotic derivatives, and we compare prices for alternative models of the underlying. Finally, we recover the celebrated results for the Wiener process under certain limits.

Aurora Bertrana : Bringing "otherness" home

“Decidida a viure al preu que sigui” underscores contemporary writer Maria-Antònia Oliver in her prologue to Aurora Bertrana’s fourth book, El Marroc sensual i fanàtic (1936). The urge to travel, to explore the world and to slake her thirst for new experiences shaped much of the personality and the work of this Girona-born writer. Taking her own travels as a starting point, Bertrana distinguished herself in the genre of travel writing on exotic countries, which at that time underwent a significant revival in Catalonia. Bertrana’s originality lies partly in the image of the woman traveller that she consciously cultivated for herself, and partly in the way she narrates her travels. This article seeks to recover this author and make visible her singular way of presenting otherness.

Introgressive hybridization of threatened European tree frogs (Hyla arborea) by introduced H. intermedia in Western Switzerland

Hybridization by introduced taxa is a major threat to native species. Characterizing human introductions is thus one of the missions of conservation geneticists. Here we survey a declining population of the regionally endangered European tree frog (Hyla arborea) in the Grangettes natural reserve (Rhone valley, Western Switzerland), where previous evidence indicated human introduction of the Italian taxon H. intermedia. We combined fast-evolving mitochondrial and nuclear markers and an extended sampling to conduct population genetic analyses of the Grangettes and putative source areas. We show that the Grangettes population is a hybrid swarm, with all individuals featuring recent nuclear admixture and mitochondrial DNA of introduced H. intermedia, most likely of proximate south Alpine origin. In contrast, H. arborea and H. intermedia hardly introgress in their natural parapatric ranges, consistent with an advanced reproductive isolation. Thus, potential hybrid incompatibilities may account for the strong decline of this population, despite important conservation efforts. Although their hybrid nature makes them a priori unworthy of any protection, we propose specific measures to recover local H. arborea gene pool and preserve tree frogs in the Grangettes, the last population remaining from this heavily impacted part of the Alps.

L'exploration temporelle comme modalité du voyage imaginaire dans la bande dessinée franco-belge (1930-1980)

In this paper, I explore the motif of time travel in science fictional French comics until the eighties. Time travel incorporates a fascinating potential for narrative representation, since moving back in time may multiply timelines, according to the well-known paradox of the grandfather. This virtuality has become very popular in novels and in movies, since In his Bootstraps (Heinlein, 1941) and La Jetée (Marker, 1962) until the recent Looper (Johnson, 2012) but it has been rarely represented in French comics before the eighties and the apparition of time paradoxes in series like "Yoko Tsuno" and, mostly, "Valérian agent spatio-temporel". Firstly, many modalities of time travel do not engender time paradoxes, like exploration of prehistoric sanctuaries, imaginary travel, or cryogenic sleep followed by an awakening if a future world with no hope to return in the past. Secondly, time travel has been mostly interpreted as a mere extension of the classic motif of the "extraordinary journey", as exemplified for centuries in fictions by Verne, Mercier, Swift, or Stevenson. Thus, the graphic potential of time travel for the representation of spectacular exotic worlds has predominated in French comic tradition, and this tendency has been encouraged by the dominant mode of publication until the end of the sixties. Indeed, complex scriptwriting involving multiple timelines would not fit the form of a weekly feuilleton addressed to a young audience, because it would be too demanding cognitively speaking. It illustrates also the dominance of graphic concerns over a taste for complex scriptwriting in many comics of this period. Still, the development of time paradoxes in Pierre Christin scriptwriting underlines the potential of the media when it is published in series of albums or in graphic novels. At the same time, Jean-Claude Mézières drawings-featuring spectacular representations of foreign worlds-show that the visual interest of spectacular time travels remains a central issue for this popular graphic medium. Cette étude porte sur le motif du voyage temporel dans la bande dessinée franco-belge de science- fiction jusque dans les années quatre-vingt. Le voyage temporel intègre un potentiel fascinant pour la représentation narrative, étant donné que le retour dans le passé est susceptible d'engendrer des lignes temporelles multiples, selon le paradoxe bien connu du « grand-père ». Cette virtualité est devenue très populaire dans les romans et dans les films, depuis In his Bootstraps (Heinlein, 1941) et La Jetée (Marker, 1962) jusqu'au récent Looper (Johnson, 2012), mais elle a rarement été représentée dans la bande dessinée franco-belge avant les années quatre-vingt et l'apparition de paradoxes temporels dans des séries comme « Yoko Tsuno » et, surtout, « Valérian agent spatio-temporel ». Tout d'abord, de nombreuses modalités du voyage dans le temps n'engendrent aucun paradoxe, par exemple l'exploration de sanctuaires préhistoriques, le voyage illusoire ou le sommeil cryogénique suivi d'un réveil dans le futur, sans espoir de revenir dans le passé. Deuxièmement, le voyage dans le temps a été plus souvent interprété comme une simple extension du motif classique du « voyage extraordinaire », tel qu'on le retrouve, depuis le XVIIIe siècle, les fictions de Verne, Mercier, Swift ou Stevenson. Ainsi, le potentiel graphique du voyage dans le temps pour la représentation de mondes exotiques spectaculaires a prédominé dans la tradition franco-belge et cette tendance a été encouragée par le mode de publication dominant jusqu'à la fin des années soixante. En effet, l'écriture de scénarios complexes impliquant de multiples lignes temporelles ne semble pas adaptée à la forme d'un feuilleton hebdomadaire destiné à un jeune public, parce qu'il aurait été trop exigeant, cognitivement parlant. Cela illustre également la prédominance de préoccupations graphiques sur l'écriture de scénarios complexes dans de nombreuses bandes dessinées de cette période. Pourtant, le développement de paradoxes temporels dans les scénarios de Pierre Christin souligne le potentiel du média quand il est publié en série d'albums ou dans des romans graphiques. Parallèlement, les dessins de Jean-Claude Mézières, qui proposent des représentations spectaculaires de mondes étrangers, montre que l'intérêt visuel du voyage dans le temps demeure une question centrale pour ce média populaire.

Protocol de conservació ex situ del Centre Ictiològic del Parc Natural del Delta de l'Ebre

En aquest Treball de Fi de Grau es pretén establir un protocol per a la conservació ex situ de les espècies que hi ha en el Centre Ictiològic del Parc Natural del Delta de l’Ebre. Les espècies que es troben en el CI són espècies vulnerables o en perill: espinós, samaruc, fartet, rabosa, llopet de riu i tritó palmat. Els objectius d’aquest protocol són: que el CI tingui un protocol propi, aprendre com funciona tot el centre, totes les espècies, com alimentar-les, com manipular-les i com tractar-les durant tot el seu cicle de vida. Un altre objectiu és el de veure si a finals d’any s’obté una alta població de cada espècie, quines són reintroduïdes, les patologies sorgides i els valors dels paràmetres químics de les basses naturals exteriors. El protocol s’elabora a partir de les pràctiques realitzades durant l’estiu del 2013 i els coneixements adquirits, la bibliografia i les dades del CI. Gràcies a això s’ha elaborat el treball. S’ha tractat la conservació ex situ; la problemàtica que sofreixen les espècies; cadascuna d’aquestes espècies; com funciona el CI a nivell de centre i a nivell de personal; les tasques que hi ha diàriament, setmanalment i ocasionalment segons les necessitats de l’estoc; el maneig sanitari; les patologies i com tractar-les; i l’anàlisi genètic. Els resultats obtinguts d’aquest protocol són els resultats numèrics obtinguts de l’any 2013 que són: 1. El gran nombre de cries nascudes de samaruc i fartet, menys de raboseta de riu, poques d’espinós i tritó palmat, i menys de llopet que tot just comença ara en el CI. 2. El total d’uns 5700 individus reitnroduits (samaruc, raboseta de riu i espinós de Girona). 3. La patologia més sorgida és el punt blanc. 4. I els paràmetres químics (amoni, nitrits, nitrats i fòsfor) no són molt elevats. La conclusió final i més important a la que arribo en fer el protocol és la gran importància que té el CI per a conservar aquestes espècies que no es saben apreciar fins que comencen a desparèixer. La existència del CI és més aviat una mesura correctora de tots els impactes que han sofert els habitatges de les espècies tractades i de la introducció d’espècies exòtiques que són una amenaça per les autòctones.

Ancient DNA of the extinct Lava shearwater (Puffinus olsoni) from the Canary Islands reveals incipient differentiation within the P. puffinus complex

The loss of species during the Holocene was, dramatically more important on islands than on continents. Seabirds from islands are very vulnerable to human-induced alterations such as habitat destruction, hunting and exotic predators. For example, in the genus Puffinus (family Procellariidae) the extinction of at least five species has been recorded during the Holocene, two of them coming from the Canary Islands.

First record of the common bream (Abramis brama) introduced to the Iberian Peninsula

This is the first record of the common bream, Abramis brama (Linnaeus, 1758), introduced into the Iberian Peninsula. Eight individuals of this cyprinid fish species were captured (of a total of 978 fish) in the Boadella Reservoir (Catalonia, Spain) on August 18, 2004. This reservoir is only 14 km away from France, where the bream is native, and contains several exotic freshwater fish that are still not widespread in Spain. The further introduction of species and the illegal translocation of the bream by anglers to other Iberian river basins should be controlled by the Spanish administration

Presence of the Nearctic Water Boatman Trichocorixa Verticalis Verticalis (Fieber, 1851) (Heteroptera, Corixidae) in the algarve region (S Portugal)

This paper describes the presence of the nearctic water boatman Trichocorixa verticalis verticalis in southern Portugal. This species has been cited recently for the first time in Europe from individuals captured in southern Spain. This species, native to Atlantic coast of America, has also been cited from New Caledonia and South Africa, and has been found in the open sea. Two kinds of introduction are reported for this species: involuntary introduction with exotic fish, and passive dispersion through marine currents and severe storms. The possibility of this kind of introduction in Europe is discussed

Low-mass diffraction dissociation at the LHC ; role of the background

A dual model with a nonlinear proton Regge trajectory in the missing mass (M_X^2) channel is constructed. A background based on a direct-channel exotic trajectory, developed and applied earlier for the inclusive electron-proton cross section description in the nucleon resonance region, is used. The parameters of the model are determined from the extrapolations to earlier experiments. Predictions for the low-mass (2 < M_X^2 < 8GeV^2) diffraction dissociation cross sections at the LHC energies are given.

Decrease in the diversity of pyrrolizidine alkaloids of Senecio pterophorus after invasion

Pyrrolizidine alkaloids (PAs) are N-based plant secondary metabolites that function as chemical defenses against vertebrate and invertebrate herbivores. PAs can be highly variable at intraspecific level, both in their absolute and relative concentrations. Changes in the chemical composition of exotic plants when they invade a new environment have been poorly explored. Here we studied the biogeographical variation on PAs in Senecio pterophorus (Asteraceae) in the native region in Eastern South Africa, an expanded region in Western South Africa, and two introduced regions in Australia and Europe. PAs in S. pterophorus were represented by the highly toxic 1,2-unsaturated PAs and the less toxic 1,2-saturated PAs. Our results show a change in the plant chemical composition after invasion. Total PAs concentrations were highest in Australia compared to any other region. Plants from Europe contained the highest relative concentrations of 1,2-saturated PAs. The positive correlation between the chemical and the genetic distances estimated between populations suggests that the chemical profiles in the non-native regions were related to the plant dispersal routes. The decrease in the chemical diversity and the change in the absolute PAs concentrations in S. pterophorus after invasion may have consequences in the interactions between plants and herbivores in the novel habitats.

Óleos essenciais no Brasil: aspectos gerais, desenvolvimento e perspectivas

Essential oils are extracted by steam distillation of plants or cold pressing of citrus fruit pericarp. They are used in food, cosmetic, personal care and pharmaceutical industries. In Brazil, oils from orange and related products contribute to near 97% to the positive commercial performance of the sector. Predatory exploitation and the availability of new sources of raw materials, with more attracting prices, changed the paradigm. Prospective studies, sustainable use of Brazilian biodiversity, domestication of exotic species with commercial relevance, the use of breeding techniques and the development of new applications for essential oils are thematic lines, usually multidisciplinary, which have been prompting the expansion of the research on essential oils. This paper presents an analysis on essential oils balance trade from 2005 to 2008 and some historical data on research and production of essential oils in Brazil.

Núcleos exóticos e síntese dos elementos químicos

We have around ninety chemical elements available in nature, which were produced mainly by nuclear reactions inside stars. The fusion reactions are the main synthesis process which generates the light and intermediate masses elements. The synthesis begins with the hydrogen burning reaching the region of iron mass nuclei. Heavier elements are synthesized by neutron capture processes, forming exotic nuclei with large neutron excess. These systems present characteristics very different from nuclei inside of stable atoms; they only occur in particular astrophysical environments or are produced artificially in special laboratory conditions. This work discusses some properties of the exotic nuclei and how they participate in the synthesis of elements.

Oceanografia e Química: unindo conhecimentos em prol dos oceanos e da sociedade

The marine environment is certainly one of the most complex systems to study, not only because of the challenges posed by the nature of the waters, but especially due to the interactions of physical, chemical and biological processes that control the cycles of the elements. Together with analytical chemists, oceanographers have been making a great effort in the advancement of knowledge of the distribution patterns of trace elements and processes that determine their biogeochemical cycles and influences on the climate of the planet. The international academic community is now in prime position to perform the first study on a global scale for observation of trace elements and their isotopes in the marine environment (GEOTRACES) and to evaluate the effects of major global changes associated with the influences of megacities distributed around the globe. This action can only be performed due to the development of highly sensitive detection methods and the use of clean sampling and handling techniques, together with a joint international program working toward the clear objective of expanding the frontiers of the biogeochemistry of the oceans and related topics, including climate change issues and ocean acidification associated with alterations in the carbon cycle. It is expected that the oceanographic data produced this coming decade will allow a better understanding of biogeochemical cycles, and especially the assessment of changes in trace elements and contaminants in the oceans due to anthropogenic influences, as well as its effects on ecosystems and climate. Computational models are to be constructed to simulate the conditions and processes of the modern oceans and to allow predictions. The environmental changes arising from human activity since the 18th century (also called the Anthropocene) have made the Earth System even more complex. Anthropogenic activities have altered both terrestrial and marine ecosystems, and the legacy of these impacts in the oceans include: a) pollution of the marine environment by solid waste, including plastics; b) pollution by chemical and medical (including those for veterinary use) substances such as hormones, antibiotics, legal and illegal drugs, leading to possible endocrine disruption of marine organisms; and c) ocean acidification, the collateral effect of anthropogenic emissions of CO2 into the atmosphere, irreversible in the human life time scale. Unfortunately, the anthropogenic alteration of the hydrosphere due to inputs of plastics, metal, hydrocarbons, contaminants of emerging concern and even with formerly "exotic" trace elements, such us rare earth elements is likely to accelerate in the near future. These emerging contaminants would likely soon present difficulties for studies in pristine environments. All this knowledge brings with it a great responsibility: helping to envisage viable adaptation and mitigation solutions to the problems identified. The greatest challenge faced by Brazil is currently to create a framework project to develop education, science and technology applied to oceanography and related areas. This framework would strengthen the present working groups and enhance capacity building, allowing a broader Brazilian participation in joint international actions and scientific programs. Recently, the establishment of the National Institutes of Science and Technology (INCTs) for marine science, and the creation of the National Institute of Oceanographic and Hydrological Research represent an exemplary start. However, the participation of the Brazilian academic community in the latest assaults on the frontier of chemical oceanography is extremely limited, largely due to: i. absence of physical infrastructure for the preparation and processing of field samples at ultra-trace level; ii. limited access to oceanographic cruises, due to the small number of Brazilian vessels and/or absence of "clean" laboratories on board; iii. restricted international cooperation; iv. limited analytical capacity of Brazilian institutions for the analysis of trace elements in seawater; v. high cost of ultrapure reagents associated with processing a large number of samples, and vi. lack of qualified technical staff. Advances in knowledge, analytic capabilities and the increasing availability of analytical resources available today offer favorable conditions for chemical oceanography to grow. The Brazilian academic community is maturing and willing to play a role in strengthening the marine science research programs by connecting them with educational and technological initiatives in order to preserve the oceans and to promote the development of society.