Características hidráulicas y efecto del estrés hídrico en cuatro clones de Eucalyptus globulus Labill

Se estudió el efecto del déficit hídrico combinado con altas temperaturas sobre la tasa de transpiración, conductancia estomática y conductividad hidráulica de tallo y raíces en planta de pequeño tamaño de cuatro clones selectos de Eucalyptus globulus. Se encontraron diferencias significativas entre clones en los valores de la conductividad hidráulica de la parte aérea por unidad de superficie foliar (Kshoot), conductividad hidráulica específica (Ks) y conductividad foliar (Kfoliar). Los menores valores de Ks y Kfoliar se midieron en el clon que alcanzó el menor crecimiento y menores valores de conductancia estomática. El máximo crecimiento se midió en el clon que alcanzó mayor valor de Kfoliar. No se encontró una relación positiva entre los valores de Kshoot y el crecimiento. El clon con mayor sensibilidad estomática a las temperaturas elevadas presentó valores altos de Kshoot, Ks y Kfoliar. Este resultado demuestra que se debe estudiar las “necesidades hidráulicas” de cada genotipo para interpretar adecuadamente la relación entre conductividad hidráulica, conductancia estomática y tasa de transpiración.______________________________We examined the combined effect of water shortage and high temperatures on the evapotranspiration rate, stomatal conductance and hydraulic conductivity of stems and roots in small-sized plants of four selected Eucalyptus globulus clones and found significant differences in hydraulic conductivity of the aerial part per leaf area unit (Kshoot), specific hydraulic conductivity (Ks) and leaf conductivity (Kleaf) between clones. The smallest Ks and Kleaf values were those for the clone exhibiting the lowest growth and stomatal conduction. On the other hand, the greatest Kleaf value was that for the clone exhibiting the highest growth. No positive correlation between Kshoot and growth was found in any clone, however. The clone with the highest stomatal sensitivity to high temperatures had large Kshoot, Ks and Kleaf values. This result shows that accurately interpreting the relationship between hydraulic conductivity, stomatal conductance and evapotranspiration in each genotype entails carefully establishing its water requirements

Optical-NIR spectroscopy of the puzzling gamma-ray source 3FGL 1603.9-4903/PMN J1603-4904 with X-shooter

The Fermi/LAT instrument has detected about two thousands Extragalactic High Energy (E > 100 MeV) gamma-ray sources. One of the brightest is 3FGL 1603.9-4903, associated to the radio source PMN J1603-4904. Its nature is not yet clear, it could be either a very peculiar BL Lac or a CSO (Compact Symmetric Object) radio source, considered as the early stage of a radio galaxy. The latter, if confirmed, would be the first detection in gamma-rays for this class of objects. Recently a redshift z=0.18 +/- 0.01 has been claimed on the basis of the detection of a single X-ray line at 5.44 +/- 0.05 keV interpreted as a 6.4 keV (rest frame) fluorescent line. We aim to investigate the nature of 3FGL 1603.9-4903/PMN J1603-4904 using optical to NIR spectroscopy. We observed PMN J1603-4904 with the UV-NIR VLT/X-shooter spectrograph for two hours. We extracted spectra in the VIS and NIR range that we calibrated in flux and corrected for telluric absorption and we systematically searched for absorption and emission features. The source was detected starting from ~6300 Ang down to 24000 Ang with an intensity comparable to the one of its 2MASS counterpart and a mostly featureless spectrum. The continuum lacks absorption features and thus is non-stellar in origin and likely non-thermal. On top of this spectrum we detected three emission lines that we interpret as the Halpha-[NII] complex, the [SII] 6716,6731 doublet and the [SIII] 9530 line, obtaining a redshift estimate of z= 0.2321 +/- 0.0004. The equivalent width of the Halpha-[NII] complex implies that PMN J1603-4904 does not follow the observational definition of BL Lac, the line ratios suggest that a LINER/Seyfert nucleus is powering the emission. This new redshift measurement implies that the X-ray line previously detected should be interpreted as a 6.7 keV line which is very peculiar.Comment: Published in Astronomy and Astrophysic

Novel designs for Penning ion traps

We present a number of alternative designs for Penning ion traps suitable for quantum information processing (QIP) applications with atomic ions. The first trap design is a simple array of long straight wires which allows easy optical access. A prototype of this trap has been built to trap Ca+ and a simple electronic detection scheme has been employed to demonstrate the operation of the trap. Another trap design consists of a conducting plate with a hole in it situated above a continuous conducting plane. The final trap design is based on an array of pad electrodes. Although this trap design lacks the open geometry of the traps described above, the pad design may prove useful in a hybrid scheme in which information processing and qubit storage take place in different types of trap. The behaviour of the pad traps is simulated numerically and techniques for moving ions rapidly between traps are discussed. Future experiments with these various designs are discussed. All of the designs lend themselves to the construction of multiple trap arrays, as required for scalable ion trap QIP.Comment: 11 pages, 10 figure

Carbon and nitrogen mineralization of organic wastes from sugarcane distilleries: vinasse and yeast waste

RAMIRAN International ConferenceIn Madeira Island (Portugal) significant amounts of wastes are generated in sugarcane distilleries, namely vinasse (the remaining fermented must after distillation) and yeast waste (the yeast surplus produced during the alcoholic fermentation). These wastes have high organic loads and low pH, leading to serious environmental problems when released directly into natural watercourses or when poorly managed (Hati et al., 2007). As a solution to avoid expensive treatments, both wastes have been used as soil amendment, since they contain important amounts of plant nutrients and organic matter (Resende et al., 2006; Parnaudeau et al., 2008). Indeed, application to soils of vinasse is a common practice in sugarcane cultivated areas and can fully substitute K and partially P on crops fertilization. Nevertheless, additional mineral nitrogen fertilization is needed when vinasse is spread in the soils (Junior et al., 2007; Oliveira et al., 2009). On the other hand, yeast waste has been considered as an excellent potential source of nitrogen for plant nutrition when applied to soils (Rezende et al., 2004). Thus, combined application of both wastes should ensure a more balanced supply of nutrients to plants. However, scarce information is available on the combine use of both wastes as fertilizer. The main objective of this study is to assess the effect of the combined application to soil of both organic materials (vinasse and yeast waste), and to evaluate its subsequent effects on nitrogen mineralization/immobilization process to supply nitrogen to crops and to preserve/restore soil carbon

34. Grip strength across Europe –North/ South and East/West divides

info:eu-repo/semantics/publishedVersio

Spatial ecology of the critically endangered Fijian crested iguana, Brachylophus vitiensis, in an extremely dense population: implications for conservation

The Critically Endangered Fijian crested iguana, Brachylophus vitiensis, occurs at extreme density at only one location, with estimates of >10,000 iguanas living on the 70 hectare island of Yadua Taba in Fiji. We conducted a mark and recapture study over two wet seasons, investigating the spatial ecology and intraspecific interactions of the strictly arboreal Fijian crested iguana. This species exhibits moderate male-biased sexual size dimorphism, which has been linked in other lizard species to territoriality, aggression and larger male home ranges. We found that male Fijian crested iguanas exhibit high injury levels, indicative of frequent aggressive interactions. We did not find support for larger home range size in adult males relative to adult females, however male and female residents were larger than roaming individuals. Males with established home ranges also had larger femoral pores relative to body size than roaming males. Home range areas were small in comparison to those of other iguana species, and we speculate that the extreme population density impacts considerably on the spatial ecology of this population. There was extensive home range overlap within and between sexes. Intersexual overlap was greater than intrasexual overlap for both sexes, and continuing male-female pairings were observed among residents. Our results suggest that the extreme population density necessitates extensive home range overlap even though the underlying predictors of territoriality, such as male biased sexual size dimorphism and high aggression levels, remain. Our findings should be factored in to conservation management efforts for this species, particularly in captive breeding and translocation programs.This work was supported by the International Iguana Foundation, the Australian National University (field work grant), the Federation of Australian Women (Georgina Sweet fellowship), the Ecological Society of Australia (student research award) and the Taronga Foundation

A fate-alternating transitional regime in contracting liquid filaments

The fate of a contracting liquid filament depends on the Ohnesorge number, the initial aspect ratio and surface perturbation. Generally, it is believed that there exists a critical aspect ratio such that longer filaments break up and shorter ones recoil into a single drop. Through computational and experimental studies, we report a transitional regime for filaments with a broad range of intermediate aspect ratios, where there exist multiple thresholds at which a novel breakup mode alternates with a no-break mode. We develop a simple model considering the superposition of capillary waves, which can predict the complicated new phase diagram. In this model, the breakup results from constructive interference between the capillary waves that originate from the ends of the filament