Soil Phosphorus Availability and Eucalypt Phosphorus Uptake from Soluble and Insoluble Sources of Phosphorus

P recovery efficiency from natural rock phosphates and a concentrated phosphate by Eucalyptus grandis plantation in relation to triple superphosphate was evaluated in field trials conducted in the cerrado area of Brazil. Two experiments were carried out in two sites of the Savanna area of Minas Gerais State, Brazil. The rates of the natural phosphates (RP)  Araxa and Patos de Minas(P2O5 24% and Ca 25%),  were 500, 1000, 2000, and 4000 kg/ha and Arafertil (33% -P2O5 and 33% Ca)concentrated rock was tested using 1000kg/ha rate only. The triple superphosphate (TP = 45% -P2O5 and 13% Ca) was applied at 250, 500, 1000, and 2000 kg/ha. Mehlich -1 and Bray -1 extractants were used to extract P from the soil. The concentration of P extracted varied with the reagent used.  Mehlich-1 extracted about 38.8% more P over the Bray -1 extractant at both sites, although, in one of the sites the extraction was 18% higher than the other. On both experimental sites, application of phosphate from both natural and concentrated forms increased tree height, stem volume and above ground dry matter production, but there was no difference between them at the rate of 1000 kg/ha. P-fixing capacity by trees increased with increasing soil P utilization efficiency. P recovery by the trees varied from 3 to 11% depending on rates and source. But P fixing capacity was higher for TP than for RP. Keywords: Araxa rock, concentrated arafertil; recovery efficiency, P-fixing capacity and eucalypt

Direct in vivo evidence on the mechanism by which nanoparticles facilitate the absorption of a water insoluble, P-gp substrate

Here we examine the mechanisms by which nanoparticles enable the oral absorption of water-insoluble, P-glycoprotein efflux pump (P-gp) substrates, without recourse to P-gp inhibitors. Both 200 nm paclitaxel N-(2-phenoxyacetyl)-6-O-glycolchitosan (GCPh) nanoparticles (GCPh-PTX) and a simulated Taxol formulation, facilitate drug dissolution in biorelevant media, unlike paclitaxel nanocrystals. Verapamil (40 mg kg−1) increased the oral absorption from low dose Taxol (6 or 10 mg kg−1) by 100%, whereas the oral absorption from high dose Taxol (20 mg kg−1) or low dose GCPh-PTX (6 or 10 mg kg−1) was largely unchanged by verapamil. There was virtually no absorption from control paclitaxel nanocrystals (20 mg kg−1). Imaging of ex-vivo rat ileum samples showed that fluorescently labelled GCPh nanoparticles are mucoadhesive and are taken up by ileum epithelial cells. GCPh nanoparticles were also found to open Caco-2 cell tight junctions. In conclusion, mucoadhesive, drug solubilising GCPh nanoparticles enable the oral absorption of paclitaxel via the saturation of the P-gp pump (by high local drug concentrations) and by particle uptake and tight junction opening mechanisms

Fractional Distillation of Organic Liquid Compounds Produced by Catalytic Cracking of Fats, Oils, and Grease

This work aims to investigate the fractional distillation of organic liquid products (OLP) obtained by catalytic cracking of palm oil (Elaeis guineensis Jacq.) at 450°C, 1.0 atm, with 5, 10, and 15% (wt) Na2CO3, using a stirred tank reactor of 143 L. The fractional distillations of OLP were carried out in laboratory scale with and without reflux using columns of different heights, and a pilot‐packed distillation column with internal reflux. OLP and distillation fractions (gasoline, kerosene, light diesel, and heavy diesel) were physicochemically characterized for density, kinematic viscosity, acid value, saponification value, refractive index, flash point, and copper strip corrosion. The OLP and light diesel fractions were analyzed by Fourier transform infrared spectroscopy (FT‐IR) and gas chromatography‐mass spectrometry (GC‐MS). For the experiments in laboratory scale, the yields of distillates decrease along with column height, with and without reflux, while those of bottoms products increase. The yields of distillates and gas increase with increasing Na2CO3 content, while those of bottoms products decrease. The densities of gasoline, kerosene, and light diesel produced in laboratory scale with reflux superpose exactly those of kerosene, light diesel, and heavy diesel produced in laboratory scale without reflux. The kinematic viscosity decreases with increasing column height for the experiments in laboratory scale. The acid values of distillation fractions decrease along with the column height for the experiments with and without reflux. The FT‐IR of distillation fractions in pilot and laboratory scales identified the presence of aliphatic hydrocarbons and oxygenates. The GC‐MS analysis identified OLP composition of 92.84% (area) hydrocarbons and 7.16% (area) oxygenates. The light diesel fraction contains 100% hydrocarbons with an acid value of 0.34 mg KOH/g, proving the technical feasibility of OLP de‐acidification by the fractional distillation process

Comparative analysis of module-based versus direct methods for reverse-engineering transcriptional regulatory networks

We have compared a recently developed module-based algorithm LeMoNe for reverse-engineering transcriptional regulatory networks to a mutual information based direct algorithm CLR, using benchmark expression data and databases of known transcriptional regulatory interactions for Escherichia coli and Saccharomyces cerevisiae. A global comparison using recall versus precision curves hides the topologically distinct nature of the inferred networks and is not informative about the specific subtasks for which each method is most suited. Analysis of the degree distributions and a regulator specific comparison show that CLR is 'regulator-centric', making true predictions for a higher number of regulators, while LeMoNe is 'target-centric', recovering a higher number of known targets for fewer regulators, with limited overlap in the predicted interactions between both methods. Detailed biological examples in E. coli and S. cerevisiae are used to illustrate these differences and to prove that each method is able to infer parts of the network where the other fails. Biological validation of the inferred networks cautions against over-interpreting recall and precision values computed using incomplete reference networks.Comment: 13 pages, 1 table, 6 figures + 6 pages supplementary information (1 table, 5 figures

Current ramps in tokamaks: from present experiments to ITER scenarios

In order to prepare adequate current ramp-up and ramp-down scenarios for ITER, present experiments from various tokamaks have been analysed by means of integrated modelling in view of determining relevant heat transport models for these operation phases. A set of empirical heat transport models for L-mode (namely, the Bohm-gyroBohm model and scaling based models with a specific fixed radial shape and energy confinement time factors of H(96-L) = 0.6 or H(IPB98) = 0.4) has been validated on a multi-machine experimental dataset for predicting the l(i) dynamics within +/- 0.15 accuracy during current ramp-up and ramp-down phases. Simulations using the Coppi-Tang or GLF23 models (applied up to the LCFS) overestimate or underestimate the internal inductance beyond this accuracy (more than +/- 0.2 discrepancy in some cases). The most accurate heat transport models are then applied to projections to ITER current ramp-up, focusing on the baseline inductive scenario (main heating plateau current of I(p) = 15 MA). These projections include a sensitivity study to various assumptions of the simulation. While the heat transport model is at the heart of such simulations (because of the intrinsic dependence of the plasma resistivity on electron temperature, among other parameters), more comprehensive simulations are required to test all operational aspects of the current ramp-up and ramp-down phases of ITER scenarios. Recent examples of such simulations, involving coupled core transport codes, free-boundary equilibrium solvers and a poloidal field (PF) systems controller are also described, focusing on ITER current ramp-down.</p

First Community-Wide, Comparative Cross-Linking Mass Spectrometry Study

The number of publications in the field of chemical cross-linking combined with mass spectrometry (XL-MS) to derive constraints for protein three-dimensional structure modeling and to probe protein-protein interactions has increased during the last years. As the technique is now becoming routine for in vitro and in vivo applications in proteomics and structural biology there is a pressing need to define protocols as well as data analysis and reporting formats. Such consensus formats should become accepted in the field and be shown to lead to reproducible results. This first, community-based harmonization study on XL-MS is based on the results of 32 groups participating worldwide. The aim of this paper is to summarize the status quo of XL-MS and to compare and evaluate existing cross-linking strategies. Our study therefore builds the framework for establishing best practice guidelines to conduct cross-linking experiments, perform data analysis, and define reporting formats with the ultimate goal of assisting scientists to generate accurate and reproducible XL-MS results

Studies on the bioavailability of zinc in rats supplementated with two different zinc-methionine compounds

Se han estudiado los efectos de los complejos zinc-metionina con la relación molar 1:1 y 1:2 como suplementación alimentaria de zinc en ratones. La obtención y la caracterización de dos complejos de zinc fueron evaluadas por análisis elemental y FTIR. El efecto de la biodisponibilidad de zinc fue estudiado por la retención en el contenido del metal en los tejidos de ratones alimentados con diversas fuentes. El compuesto 1:1 era un complejo del catión de fórmula [Zn(C5H10NO2S)(H2O)2]+ , muy soluble en agua, mientras que el compuesto 1:2 era un complejo neutro de fórmula [Zn(C5H10NO2S)2], solamente soluble debajo de pH 3. Los espectros de FTIR de ambos complejos demostraron franjas de absorción fuertes debido al estiramiento del C-O del grupo del aminoácido (extendiéndose de νs(C=O) 1638 cm–1 y νas(C-O) 1414 cm–1 , en ZnMet, a νs(C=O) 1608 cm–1 y νas(C-O) 1426 cm–1 , en Zn(Met)2, cambiados de posición perceptiblemente las frecuencias asimétricas aumentan y las frecuencias simétricas disminuyen con respecto a la metionina libre νs(COO) 1582 cm–1 y νas(COO) 1415 cm–1 , 1720 cm–1 El resultado de la alimentación fue observado claramente en la eliminación fecal del zinc de los animales del grupo de control perceptiblemente diferente (P < 0,05) que los tratados de los . animales con dietas suplementadas con zinc, pero no se observó en la eliminación urinaria. El estudio indica que el contenido del zinc en las heces recogidas en 14 días para toda la dieta del zinc era perceptiblemente diferente (P < 0,05) del grupo de control (tratamiento de los animales con prácticamente ausencia de zinc). La retención del zinc en los grupos a los que se administraron compuestos de metionina fue perceptiblemente más alta que la alimentación con dieta de ZnSO4 y de ZnO. En conclusión, estos datos indican que el uso del los complejos zincmetionina constituyen una herramienta valiosa a la biodisponibilidad del aumento del zinc, no obstante sin diferencias significativas entre ZnMet y la forma Zn(Met)2.The effects of zinc-methionine complexes with molar relation 1:1 and 1:2 have been examined as nutritional supplements in rats. The synthesis and characterization of two compounds were studied by elemental analysis and FTIR. The bioavailability effect was studied by zinc retention and its content in rat tissues in rats fed with different zinc-methionine complexes. The compound 1:1 was a cation complex of formula [Zn(C5H10NO2S)(H2O)2]+ , very water soluble, while the compound 1:2 was a neutral complex of formule [Zn(C5H10NO2S]2], only soluble in pH below 3. FTIR spectra of both complexes show strong absorption bands due to C-O stretching of the amino acid group (ranging from νs(C=O) 1638 cm–1 and νas(C-O) 1414 cm–1 , in ZnMet, to νs(C=O) 1608 cm–1 and νas(C-O) 1426 cm–1 , in Zn(Met)2) shifted significantly with respect to the ones observed for the free methionine (νas(COO) 1582 cm–1 and νs(COO) 1415 cm–1 ,1720 cm–1 ). The nutritional result in the zinc fecal elimination of the animals of the control group was significantly different (P < 0.05) to the ones observed for the animals treaties with zinc supplemented diets, though this was not observed during urinary elimination. This study indicates that the content of zinc in the feces collected in 14 days for all zinc diet were significantly different (P<0.05) from the control group (animals treaties with zinc practically absent). The retention of zinc in the groups treated with the methionine compounds was significantly higher than the ones fed with ZnSO4 and ZnO diet. In conclusion, these data indicate that the use of zinc-methionine chelates is a valuable tool to increase bioavailability of zinc, however without significant differences between ZnMet and Zn(Met)2.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Reduced membrane fluidity of a SigX deficient strain results in altered carboncatabolic repression response in Pseudomonas aeruginosa

International audienc