39-K Bose-Einstein condensate with tunable interactions

We produce a Bose-Einstein condensate of 39-K atoms. Condensation of this species with naturally small and negative scattering length is achieved by a combination of sympathetic cooling with 87-Rb and direct evaporation, exploiting the magnetic tuning of both inter- and intra-species interactions at Feshbach resonances. We explore tunability of the self-interactions by studying the expansion and the stability of the condensate. We find that a 39-K condensate is interesting for future experiments requiring a weakly interacting Bose gas.Comment: 5 page

The Irish Social Partnership and the "Celtic Tiger" Phenomenon

Ireland is the miracle economy of the 1990s. In 15 years, it transformed itself from one of the poorest countries in Europe into one of the richest. Ireland’s record compares favorably not just with other, much touted examples of economic success in the last few years, like the Netherlands and the US, but also with Asian “tigers,” even before the latter’s economic setbacks of the late 1990s. Understanding the sources of Ireland’s economic success is therefore relevant for a much wider audience than just the people of the Emerald Isle.Introduction 1. The development of the Irish social partnership 2. Does social partnership matter? 3. Multinationals, social partnership, and the “Irish disease” a) The role of multinationals b) The moral economy of wages and the “Irish disease” c) The effects of social partnership 4. The politics of wage restraint in Ireland a) Pro-partnership coalitions b) The problem of compliance 5. Concluding remarks Reference

Feshbach resonances in ultracold K(39)

We discover several magnetic Feshbach resonances in collisions of ultracold K(39) atoms, by studying atom losses and molecule formation. Accurate determination of the magnetic-field resonance locations allows us to optimize a quantum collision model for potassium isotopes. We employ the model to predict the magnetic-field dependence of scattering lengths and of near-threshold molecular levels. Our findings will be useful to plan future experiments on ultracold potassium atoms and molecules.Comment: 7 pages, 6 figure

Co-digestion of macroalgae for biogas production: an LCA-based environmental evaluation

Algae represent a favourable and potentially sustainable source of biomass for bioenergy-based industrial pathways in the future. The study, performed on a real pilot plant implemented in Augusta (Italy) within the frame of the BioWALK4Biofuels project, aims to figure out whether seaweed (macroalgae) cultivated in near-shore open ponds could be considered a beneficial aspect as a source of biomass for biogas production within the co-digestion with local agricultural biological waste. The LCA results confirm that the analysed A and B scenarios (namely the algae-based co-digestion scenario and agricultural mix feedstock scenario) present an environmental performance more favourable than that achieved with conventional non-renewable-based technologies (specifically natural gas - Scenario C). Results show that the use of seaweed (Scenario A) represent a feasible solution in order to replace classical biomass used for biofuel production from a land-based feedstock. The improvement of the environmental performances is quantifiable on 10% respect to Scenario B, and 38 times higher than Scenario

Analysis of the absorption and emission spectra of U4+ in α-ThBr 4

The low temperature form α-ThBr4 has a scheelite structure I41/a in which the tetravalent uranium occupies the thorium site which is S4. Assuming that the ground state remains Γ 4 as in the β-ThBr4 form, the polarized absorption spectrum at 4.2 K shows that D2d is a good approximation. A peculiarity of this host is the exaltation of very numerous fluorescences of U4+ which permit to assign four Stark levels of the ground state 3H4 : Γ5 at 110 cm-1, Γ 1 at 473 cm-1, Γ1 at 623 cm-1 and Γ5 at 830 cm-1. 30 levels have been assigned and the crystal field parameters of U4+ (5f2) have been calculated in the D2d approximation : B20 = - 382, B40 = - 3 262, B44 = - 1734, B60 = - 851 and B64 = - 1828 cm-1. It is interesting to note that a small distortion in the scheelite structure of the α-ThBr4 compared with the zircon structure β-ThBr4 induces important changes in the crystal field parameters

Parametrization of 5f-5f Transition Probabilities Between Stark Levels of U 3+ in LiYF4

In order to simulate intensities of the 5f-5f transitions of U3+ in LiYF4, we applied the Judd-Ofelt theory. Because of the large crystal-field splitting of the J-multiplets in the actinides, a set of phenomenological intensity parameters Bλkq is introduced to describe the transition probabilities between the crystal-field sublevels of U3+. The intensities of the absorption transitions between the crystal field levels calculated and a set of six phenomenological intensity parameters give a rather good simulation of the experimental intensities, and the applicability of the Judd-Ofelt theory is discussed for the 5f→ 5f transitions of the actinides. From these values, the oscillator strengths between the excited states involved in the laser transition 4I11/2→4I9/2 are calculated and the corresponding radiative lifetime is compared to the experimental one. Moreover, a comparison between the actinide ion U3+ (5f3) and the lanthanide ions Nd3+ (4f3) and Er3+ (4f11) in LiYF4 is made

VvMYB60 expression is restricted to guard cells and correlates with stomatal conductance in the grape leaf

Grapevine (Vitis vinifera L.) is traditionally grown under non-irrigated field conditions in many cropping environments, including dry lands and semiarid regions. Good osmotic adjustment, architecture of the root system, xylem embolism and efficient stomatal control of water loss account for the drought resistance traits of the Vitis genus. Among these features, the regulation of stomatal activity is of particular relevance, as it directly shapes the isohydric versus anysohydric behaviour of different grape species and cultivars. Increasing evidence indicates a role for the transcriptional control of gene expression in modulating stomatal responses to both biotic and abiotic stimuli. R2R3 MYB transcription factors have been identified as key regulators of stomatal opening and transpirational water loss under stress in different plant species. We identified the grape gene VvMYB60 (VIT_08s0056g00800) as the functional ortholog of AtMYB60 (At1g08810), involved in the regulation of stomatal activity in Arabidopsis. Here, we report results from the analysis of VvMYB60 expression in the grape leaf, including: 1. The qPCR analyses of stomata-enriched grape epidermal fragments and lasermicrodissected guard cells; 2. The confocal analysis of grape leaves agro-infiltrated with the VvMYB60promoter::GFP construct; 3. The analysis of changes in VvMYB60 expression relatively to variations in stomatal conductance (gs) in plants grown under control or drought stress conditions. As a whole our data confirmed the guard cell-specificity of VvMYB60 expression in the grape leaf and revealed a positive correlation between gs and the relative abundance of the VvMYB60 transcripts, thus substantiating the notion of VvMYB60 being a transcriptional mediator of stomatal activity in grape