1,470 research outputs found

    Exploring the importance of sulfate transporters and ATP sulphurylases for selenium hyperaccumulation\u2014a comparison of Stanleya pinnata and Brassica juncea (Brassicaceae)

    Get PDF
    Selenium (Se) hyperaccumulation, the capacity of some species to concentrate Se to levels upwards of 0.1% of dry weight, is an intriguing phenomenon that is only partially understood. Questions that remain to be answered are: do hyperaccumulators have one or more Se-specific transporters? How are these regulated by Se and sulfur (S)? In this study, hyperaccumulator Stanleya pinnata was compared with related non-hyperaccumulator Brassica juncea with respect to S-dependent selenate uptake and translocation, as well as for the expression levels of three sulfate/selenate transporters (Sultr) and three ATP sulphurylases (APS). Selenium accumulation went down ~10-fold with increasing sulfate supply in B. juncea, while S. pinnata only had a 2\u20133-fold difference in Se uptake between the highest (5 mM) and lowest sulfate (0 mM) treatments. The Se/S ratio was generally higher in the hyperaccumulator than the non-hyperaccumulator, and while tissue Se/S ratio in B. juncea largely reflected the ratio in the growth medium, S. pinnata enriched itself up to 5-fold with Se relative to S. The transcript levels of Sultr1;2 and 2;1 and APS1, 2, and 4 were generally much higher in S. pinnata than B. juncea, and the species showed differential transcript responses to S and Se supply. These results indicate that S. pinnata has at least one transporter with significant selenate specificity over sulfate. Also, the hyperaccumulator has elevated expression levels of several sulfate/selenate transporters and APS enzymes, which likely contribute to the Se hyperaccumulation and hypertolerance phenotype

    “The Right to the City” An Ecosystemic Approach to Better Cities, Better Life

    Get PDF
    Urbanism is a focus on cities and urban areas, their geography, economies, politics, social characteristics, as well as the effects on, and caused by, the built environment; it is linked to various aspects of quality of life: education, culture, justice, labour, environment, health, safety, housing, leisure, transport, consumption. This year, the United Nations proposed the following questions for the citizens of the world: What is the best thing about your city? What's the worst thing about your city? What do you want the authorities to do about it? What can you do about it? It is a clear attempt to foster civic participation and personal engagement, but to make things happen it is necessary to create active socio-cultural niches at many societal levels.Urbanism; politics; education; culture; justice

    Effects of selenium biofortification on crop nutritional quality

    Get PDF
    Selenium (Se) at very low doses has crucial functions in humans and animals. Since plants represent the main dietary source of this element, Se-containing crops may be used as a means to deliver Se to consumers (biofortification). Several strategies have been exploited to increase plant Se content. Selenium assimilation in plants affects both sulphur (S) and nitrogen (N) metabolic pathways, which is why recent research has also focused on the effect of Se fertilization on the production of S- and N- secondary metabolites with putative health benefits. In this review we discuss the function of Se in plant and human nutrition and the progress in the genetic engineering of Se metabolism to increase the levels and bioavailability of this element in food crops. Particular attention is paid to Se biofortification and the synthesis of compounds with beneficial effects on health

    Familles du Sud

    Get PDF

    Improved flexibility and equity for airspace users during demand-capacity imbalance - an introduction to the user-driven prioritisation process

    Get PDF
    ATFM slot-swapping represents the first step towards the participation of airspace users (AUs) in air traffic management and airport collaborative processes. SESAR is advancing this through development of the user driven prioritisation process (UDPP) to achieve additional flexibility for AUs to adapt their operations in a more cost-efficient manner in the presence of unforeseen demand and capacity imbalances that require the application of delays to flights. The contribution of this paper is twofold: (i) to present the challenges achieved so far with respect to UDPP concepts, in particular regarding fleet delay apportionment and selective flight protection; (ii) to pave the way towards future UDPP concepts through the introduction of enhanced selective flight protection

    Invasive Group A Streptococcal Infections, Clinical Manifestations and Their Predictors, Montreal, 1995–2002

    Get PDF
    Specific clinical manifestations of invasive group A streptococcal infection appear to develop not in response to the pathogen, but rather to host or environmental factors
    corecore