Models for predicting fire ignition probability in graminoids from boreo-temperate moorland ecosystems

An increase in both the frequency and severity of wildfires in boreo–temperate ecosystems is predicted. Therefore, to develop efficient fire rating systems, the relationship between the fuel moisture content (FMC) of vegetation and ignition thresholds needs to be determined. We developed fire ignition probability models for three graminoid species collected in central England, but common in boreo–temperate ecosystems (Eriophorum angustifolium, E. vaginatum and Molinia caerulea). Specifically, we assessed through laboratory experiments (1) seasonal differences between early spring and late summer in fuel traits such as height, fuel load, fuel bulk density and dead fuel load proportion, and (2) the role of these fuel traits, environmental conditions and dead FMC in determining the probability of ignition. There were seasonal differences in fuel traits among species, with an increase in dead fuel load proportion after winter. The dead FMC was the only variable determining initial sustained ignitions. However, the seasonal differences in dead fuel were not sufficient to affect the FMC threshold at which graminoids start to ignite. Graminoids begin to ignite at high levels of dead FMC, and there are differences between species (from 36.1% to 48.1%). This work assists in improving fire ignition predictions in graminoid-dominated ecosystems by providing warnings based on critical moisture thresholds.</jats:p

Maximum Entanglement in Squeezed Boson and Fermion States

A class of squeezed boson and fermion states is studied with particular emphasis on the nature of entanglement. We first investigate the case of bosons, considering two-mode squeezed states. Then we construct the fermion version to show that such states are maximum entangled, for both bosons and fermions. To achieve these results, we demonstrate some relations involving squeezed boson states. The generalization to the case of fermions is made by using Grassmann variables.Comment: 4 page

The effect of some processing conditions on the characteristics of biodegradable microspheres obtained by an emulsion solvent evaporation process

Unloaded microspheres were prepared from polyhydroxybutyrate (PHB) and polyhydroxybutyrate-co-valerate (PHB-HV) polymers using an oil-in-water emulsion solvent evaporation method. The study was conducted to evaluate how the polymer and some process parameters affect properties of the final microspheres such as particle size, superficial area, zeta potential, surface morphology and microsphere degradation. The variables included surfactant concentration in the emulsion water phase and solvent composition. From the results, it was found that the parameters affecting microsphere size the most were surfactant concentration in the emulsion water phase and solvent composition. Properties such as zeta potential, surface area and surface morphology remained pratically unchanged over the range of the processing conditions studied here.011

Characterization of long-term motor deficits in the 6-OHDA model of Parkinson's disease in the common marmoset.

Research aimed at developing new therapies for Parkinson's disease (PD) critically depend on valid animal models of the disease that allows for repeated testing of motor disabilities over extended time periods. We here present an extensive characterization of a wide range of motor symptoms in the 6-OHDA marmoset model of PD when tested over several months. The severity of motor deficits was quantified in two ways: (i) through manual scoring protocols appropriately adapted to include species specific motor behavior and (ii) using automated quantitative motion tracking based on image processing of the digital video recordings. We show that the automated methods allow for rapid and reliable characterization of motor dysfunctions, thus complementing the manual scoring procedures, and that robust motor symptoms lasting for several months could be induced when using a two-stage neurotoxic lesioning procedure involving one hemisphere at a time. This non-human primate model of PD should therefore be well suited for long-term evaluation of novel therapies for treatment of PD

Effect of the concentration by reverse osmosis of grape juice on its aroma profile.

Reverse osmosis (RO) is a membrane process applied for fruit juices concentration as it is carried out under mild temperature, preserving the natural aroma profile of these beverages. In Brazil, grape juice is usually concentrated during the crop season that can results in methyl anthranilate loss, the main substance of grape juice characteristic aroma. The aim of this work was to evaluate the effect of the RO temperature for the concentration of grape juice and its influence on the aroma profile. The single strength red grape juice (SGJ) produced with Vitis labrusca grapes (Concord, Isabella, BRS Rubea and BRS Violet cv.) was concentrated at 50oC,30oC and 20oC, and 60 bar transmembrane pressure. The RO processes were carried out in a plate and frame unit with composite membranes presenting 98% rejection to NaCl. Volatile compounds characterization was accomplished by SPME extraction with PDMS/DVB fibers and the aroma profile was determined by gas chromatography using flame ionization detector and mass spectrometer. For the Quantitative Descriptive Sensory analysis, ten panelists evaluated eight samples of the reconstituted grape juices (12,7oBrix), including the SGJ, the three concentrated juices and four commercial products (E, F, G, H) in a nine point hedonic scale, where 1 was absence or weak and 9 represented strong characteristic aroma. Permeation of volatile compounds was observed in all RO processes at all evaluated temperatures. The relative peak area for methyl anthranilate was 0,9% for SGJ; 0,6%, 0,9% and 1,0% for the juices processed by RO at 50oC, 30oC and 20oC, respectively; and 9,9% for product E. Sensory tests confirmed that product E presented the highest (6,88) and the juice processed at 50oC the lowest mean score (4,34). But the juice processed by RO at 30oC and 20oC were the most favorable for the preservation of grape juice aroma

Efeitos dos produtos fitossanitários utilizados na cultura da cana-deaçúcar sobre adultos do parasitóide Trichogramma galloi.

SICONBIOL 2011