Arsenic uptake and metabolism in arsenic resistant and nonresistant plant species

Elevation of arsenic levels in soils causes considerable concern with respect to plant uptake and subsequent entry into wildlife and human food chains, Arsenic speciation in the environment is complex, existing in both inorganic and organic forms, with interconversion between species regulated by biotic and abiotic processes. To understand and manage the risks posed by soil arsenic it is essential to know how arsenic is taken up by the roots and metabolized within plants. Some plant species exhibit phenotypic variation in response to arsenic species, which helps us to understand the toxicity of arsenic and the way in which plants have evolved arsenic resistances. This knowledge, for example, could be used produce plant cultivars that are more arsenic resistant or that have reduced arsenic uptake. This review synthesizes current knowledge on arsenic uptake, metabolism and toxicity for arsenic resistant and nonresistant plants, including the recently discovered phenomenon of arsenic hyperaccumulation in certain fern species. The reasons why plants accumulate and metabolize arsenic are considered in an evolutionary context. © New Phytologist.

Impacts of culling and exclusion of browsers on vegetation recovery across New Zealand forests

Introduced browsing animals negatively impact New Zealand's indigenous ecosystems. Eradicating introduced browsers is currently unfeasible at large scales, but culling since the 1960s has successfully reduced populations to a fraction of their earlier sizes. Here we ask whether culling of ungulates has allowed populations of woody plant species to recover across New Zealand forests. Using 73 pairs of permanent fenced exclosure and unfenced control plots, we found rapid increases in sapling densities within exclosures located in disturbed forests, particularly if a seedling bank was already present. Recovery was slower in thinning stands and hampered by dense fern cover. We inferred ungulate diet preference from species recovery rates inside exclosures to test whether culling increased abundance of preferred species across a national network of 574 unfenced permanent forest plots. Across this network, saplings were observed irrespective of their preference to ungulates in the 1970s, but preferred species were rarer within disturbed sites in the 1990s after long-term culling and despite nationwide increases in sapling densities. This indicates that preferred species are relatively heavily affected by browsing after culling, presumably because remaining animals will increase consumption of preferred species as competition is reduced. Our results clearly suggest that culling will not return preferred plants to the landscape immediately, even given suitable conditions for regeneration. Complete removal of ungulates rather than simply reducing their densities may be required for recovery in heavily browsed temperate forests, but since this is only feasible at small spatial scales, management efforts must target sites of high conservation value. © 2012 Elsevier Ltd.

Dissenting Exhibitions by Artists (1968-1998). Reframing Marxist Exhibition Legacy.

The goal of this thesis is to look at the critical and dissenting value of exhibitions through the examination of four cases studies, based on six exhibitions taking place between 1968 and 1998 in Latin and North America. The exhibitions belong to the history of modern and contemporary exhibitions and curating, a field of research and study that has only started to be written about in the last two decades. This investigation contributes to it, in its creation of new genealogies by connecting previously overlooked antecedents, or by proposing new relations within established lineages, at the intersection of a specific historiography; to address exhibitions, a tradition of artists acting as curators and an emerging history of curating. The examined exhibitions were put together by artists or artist collectives and were placed in a liminal position between artistic and curatorial practice. All the cases presented a distinct proposal in relation to art and social change, a fact that connects them, in their aims and modus operandi, to a Marxist and neo-Marxist critical and transformative legacy. The cases address the following connections: exhibition as political site (Tucumán Arde, 1968); exhibition as social space (The People’s Choice (Arroz con Mango), 1981); exhibition as encounter (Rooms with a view, We the People, Art/Artifact, 1987-88); and exhibition as an exchange situation (El Museo de la Calle, 1998-2001). Key to their analysis is the concept of dissensus, as put forward by Jacques Rancière. Within this theoretical framework, these exhibitions put into practice particular cases of dissensus in a given distribution of the sensible. All of them tried to deal with their thematic concerns by performing them as a praxis. They dissent with the way in which reality was formatted in their historical moment and challenge the exhibition medium itself opening new ways of doing and making in the exhibition field. Therefore, in this thesis the dissenting value of exhibitions is closely related to its main features as a medium, namely their temporality, heterogeneity and flexibility, which contribute to their potential for creative analysis and propositioning. In the case of these exhibitions, this capability is brought into play for institutional interrogation, for offering alternative cultural narratives and also for inspiring new imaginary realms.

Validação do método de análise de espectrofotómetria de absorção atómica/emissão de chama para determinação de minerais na fermentação de medronho (Arbustus unedo L.)

Dissertação mest., Qualidade em análises, Universidade do Algarve, 2006

Monomeric and oligomeric flavan-3-ols and antioxidant activity of leaves from different Laurus sp.

The phenolic profile and antioxidant activity of three endemic Laurus sp. from Portugal were analysed. Dried leaves of L. nobilis L., L. azorica (Seub.) Franco, and L. novocanariensis Rivas Mart., Lousã, Fern. Prieto, E. Días, J. C. Costa & C. Aguiar, collected in the mainland and in the Azores and Madeira archipelagos, respectively, were used to prepare different extracts (aqueous, ethanolic and hydroalcoholic). They were studied regarding their DPPH˙ scavenging activity, total phenolic and flavonoid contents, and the main phenolic compounds were identified by HPLC-DAD-ESI-MS/MS. Total flavonoid contents were 30.1, 46.3, and 36.7 mg of epicatechin equivalents per g of sample (dry weight) for L. nobilis, L. azorica and L. novocanariensis, respectively. Epicatechin was the major compound, representing ∼12.1% of total flavan-3-ols in L. nobilis, ∼25.6% in L. azorica, and ∼19.9% in L. novocanariensis. Although all samples presented a similar phenolic profile, significant differences were observed in their total contents and antioxidant activity.

Pharmacokinetics and pharmacogenomics of once-daily raltegravir and atazanavir in healthy volunteers.

Atazanavir inhibits UDP-glucuronyl-transferase-1A1 (UGT1A1), which metabolizes raltegravir, but the magnitude of steady-state inhibition and role of the UGT1A1 genotype are unknown. Sufficient inhibition could lead to reduced-dose and -cost raltegravir regimens. Nineteen healthy volunteers, age 24 to 51 years, took raltegravir 400 mg twice daily (arm A) and 400 mg plus atazanavir 400 mg once daily (arm B), separated by ?3 days, in a crossover design. After 1 week on each regimen, raltegravir and raltegravir-glucuronide plasma and urine concentrations were measured by liquid chromatography-tandem mass spectrometry in multiple samples obtained over 12 h (arm A) or 24 h (arm B) and analyzed by noncompartmental methods. UGT1A1 promoter variants were detected with a commercially available kit and published primers. The primary outcome was the ratio of plasma raltegravir C(tau), or concentration at the end of the dosing interval, for arm B (24 h) versus arm A (12 h). The arm B-to-arm A geometric mean ratios (95% confidence interval, P value) for plasma raltegravir C(tau), area under the concentration-time curve from 0 to 12 h (AUC(0-12)), and raltegravir-glucuronide/raltegravir AUC(0-12) were 0.38 (0.22 to 0.65, 0.001), 1.32 (0.62 to 2.81, 0.45), and 0.47 (0.38 to 0.59, <0.001), respectively. Nine volunteers were heterozygous and one was homozygous for a UGT1A1 reduction-of-function allele, but these were not associated with metabolite formation. Although atazanavir significantly reduced the formation of the glucuronide metabolite, its steady-state boosting of plasma raltegravir did not render the C(tau) with a once-daily raltegravir dose of 400 mg similar to the C(tau) with the standard twice-daily dose. UGT1A1 promoter variants did not significantly influence this interaction.

Misogyny in Health Professions? An Analysis of the Dalhousie Dentistry Scandal

Commentaire / Commentary

Programa de an??lisis estad??stico para estudios m??dicos y biol??gicos

Se presenta experiencia educativa que propone la elaboraci??n de materiales relacionados con el ciclo formativo de grado superior sobre higiene bucodental. Se realiza en el IES Aynadamar en Granada. Los objetivos son: colaborar en la realizaci??n de estudios de salud comunitaria y realizar programas de prevenci??n bucodental. El proceso consta de varias fases: b??squeda de informaci??n y elaboraci??n de materiales; estudio de programas inform??ticos; elaboraci??n de un cuestionario para una encuesta sobre salud mental; estudio de la salud bucodental del alumnado del centro.

La programaci??n de aula digital

Se presenta experiencia educativa que plantea ordenar todos los recursos TICs de los que se dispone en el centro. Se realiza en el CEIP Virgen del Rosario en Jayena, Granada. Los objetivos son: elaborar una herramienta ??til para el profesorado en su d??a a d??a; formaci??n del profesorado en materiales de nuevas tecnolog??as.

Mat??riel pour les sections Europ??ennes. 'Material para las secciones europeas'

Se presenta experiencia educativa que propone la elaboraci??n de materiales biling??es para la ense??anza del alumnado. Se realiza en el IES Virgen de la Caridad en Loja, Granada. Los objetivos son: dar la posibilidad al profesorado de elaborar su propio material en franc??s para su posterior aplicaci??n en clase; elaborar un material propio y pr??ctico en sinton??a con lo que hemos aprendido; plantear tareas al alumnado utilizando el franc??s como medio de comunicaci??n; conocer un poco m??s la realidad franc??s a trav??s de una prueba deportiva de tal envergadura, llev??ndolas a materias tan distintas como las matem??ticas y la geograf??a e historia.

??C??mo nos gusta bailar!

Se presenta experiencia educativa que propone la m??sica y la danza como medio de expresi??n del alumnado. Se realiza en el CEIP Ntra. Sra. del Rosario en Chimeneas, Granada. Los objetivos son: conocer algunas de las manifestaciones art??sticas y culturales de su entorno m??s cercano; coordinar las diferentes partes del esquema corporal; desarrollar la autoestima y la confianza en s?? mismo; desarrollar una autoestima progresiva; intervenir de forma directa en las manifestaciones art??sticas de su localidad.

La rutina del 'desayuno' : momento educativo que abarca todas las ??reas de experiencia

Se presenta experiencia educativa que propone la actividad del desayuno como oportunidad para reforzar h??bitos higi??nicos, alimenticios y sociales en la etapa de Educaci??n Infantil. Se realiza en el CEIP Padre Manj??n en Hu??tor-Tajar, Granada. Los objetivos son: tener una imagen ajustada y positiva de s?? mismo, identificando sus caracter??sticas y cualidades personales al manifestar sus gustos o preferencias con respecto a ciertos alimentos; relacionarse con el grupo en el transcurso de la actividad del desayuno, tomando progresivamente en consideraci??n a los otros; ayudar al alumnado a relacionarse con el mundo exterior y proporcionarle las bases necesarias para comunicarse en ??l y poder representarlo.

Un mercadillo de valores

Se presenta experiencia educativa que propone la construcci??n de un mercadillo y la participaci??n de la comunidad educativa para potenciar la educaci??n en valores entre el alumnado. Se realiza en el CEIP Mar??n Ocete en Alfacar, Granada. El mercadillo est?? organizado por distintos talleres a modo de 'tiendas'. Las distintas tiendas son: de la solidaridad, de las tradiciones y costumbres, de la justicia, de la salud y del medio ambiente, de la alegr??a, de la amistad, del esfuerzo, del respeto y de la paz.

Proyecto de lectura en familia : la fuente del saber

Se presenta experiencia educativa que propone involucrar a las familias en el h??bito de la lectura para potenciar este h??bito en sus hijos e hijas. Se realiza en el CEIP Mar??n Ocete en Alfacar, Granada. Los objetivos son: desarrollar el gusto por la lectura descubriendo los valores que esta nos aporta; hacer de la biblioteca un lugar agradable de animaci??n a la lectura y utilizaci??n de sus fondos; hacer c??mplices a los padres-madres de la importancia y beneficios de la lectura.