International sorghum trade: United States beyond the Mexican dependency?

This research proposes the estimation of a partial equilibrium econometric and simulation international trade model for sorghum: United States and Mexico component. Sixteen equations were simultaneously estimated and validated as a system using seemingly unrelated regression. Results on parameter estimates agree with economic theory and a working model for simulation and forecast was obtained. Forecast scenarios suggest that the dependency of sorghum trade between US and Mexico will continue.Supply, Demand, NAFTA, International trade, Sorghum, International Relations/Trade,

Interaction of protein synthesis initiation factor 2 from Xenopus laevis oocytes with GDP and GTP analogs

AbstractThe structural specificity of the purified protein synthesis initiation factor 2 (eIF-2) from X. laevis ovary towards analogs of GTP and GDP was studied. The relative affinity of the structural analogs was measured by their capacity to inhibit the formation of the [3H]GDP·eIF-2 binary complex. The results obtained demonstrate that modifications in the ribose moiety are well tolerated by eIF-2 which binds dGTP, 2′,3′-dialdehyde GTP (oGTP) and 2′,3′-dialdehyde GDP (oGDP) and even the dinucleotide cytidylyl(5′-3′)guanosine 5′-triphosphate (pppGpC). Substitution in the polyphosphate chain by phosphorothioate groups in the β and γ positions (GDPβS or GTPγS) does not abolish the affinity for the nucleotides and the presence of an imido group between the β and γ phosphates in guanyl-5′-yl imidodiphosphate (GppNHp) still permits a weaker but significant binding. Guanine 5′-O-(2-fluorodiphosphate) (GDPβF) has an affinity considerably lower than GDPβS. Methylation of position 7 of the guanine (7-m GDP), however, completely eliminates the interaction of GDP with eIF-2. The analogs tested can be listed in the following order of descending affinities: GDP > GDPβS > oGDP⩾ GTPγS > GDPβF > pppGpC > GTP > GppNHp > oGTP ⪢ 7-m GDP. Assays of the capacity of GTP analogs to form a ternary complex of the type met-tRNAi·GTP·eIF-2 or of GDP analogs to inhibit the formation of this complex reflect, in general, the same order of relative affinities except for pppGpC, which is weaker in its capacity to form a ternary complex than GppNHp or oGTP, although it has a higher affinity than these compounds in the formation of a binary complex

Chains of Cobalt Doped Magnetosomes Extracted from AMB-1 Magnetotactic Bacteria for Application in AMF hyperthermia

International audienceWe report themagnetic properties and heating efficiency of cobalt doped chains of magnetosomes extracted frommagnetotactic bacteria for applications in alternativemagnetic field cancer therapy. The changes of the magnetic properties of the chains of magnetosomes observed in the presence of cobalt are characterized by an enhancement of the magnetocrystalline anisotropy from Keff ∼ 12 KJ/m3 in the absence of cobalt up to Keff ∼ 104 KJ/m3 in the presence of cobalt. We show that these changes are only observed for the magnetosomes organized in chains. Furthermore, the SAR of the extracted chains of magnetosomes mixed in solution and exposed to an oscillating magnetic field of field amplitude 80 mT and frequency 183 kHz is shown to increase from∼400W/gFe for the undoped chains ofmagnetosomes up to ∼500 W/gFe for the cobalt doped chains of magnetosomes

Irrigação no Nordeste do brasil.

Irrigação no mundo; Irrigação no Nordeste; Perspectivas de irrigação no Nordeste, potencialidades.bitstream/item/181047/1/FL-05641.pd

APROXIMACIÓN EXPERIMENTAL AL TRATAMIENTO DE AGUA DE COLA

Se centrifugó el agua de cola producida por una fábrica de harina de sardina ubicada en el noroeste de México, a fin de recuperar sólidos orgánicos potencialmente útiles y evitar un posible caso de contaminación marina. El sobrenadante fue tratado por medio de ajuste de pH. Por medio de la centrifugación se removieron 43, 36, 18 y 95 % de sólidos totales, proteínas, cenizas y lípidos, respectivamente. El ajuste de pH en la zona alcalina (estudio preliminar) no fue eficiente para la reducción de la demanda bioquímica de oxígeno (DBO5) y la demanda química de oxígeno (DQO). No obstante, modificando el pH en las zonas alcalina y ácida (tratamiento experimental), se logró recuperar de 58 a 64 % de compuestos nitrogenados (proteínas, péptidos, aminoá- cidos) y de 24 a 55 % de cenizas. La fracción soluble (FS2) presentó más de 65 % de transmitancia; los niveles de DBO5 y DQO disminuyeron a 93 y 91 %, respectivamente. Aunque la fracción soluble final (FS2) sobrepasa los límites permisibles, se provee información básica experimental con el fin de proponer estrategias complementarias que ayuden a mejorar el tratamiento fisicoquímico y contribuir a la reducción del material orgánico contaminante causado por el agua de cola

CHEMICAL FERTILIZATION THROUGH FERTIRRIGATION IN THE EVALUATION OF THE BIOCHEMICAL CHARACTERISTICS OF THE WATERMELON FRUITS

The objective of this work was to evaluate the effects of splitting in three different doses of phosphorus and potassium, combined with each other, and it was applied fertirrigation in watermelon crop, and to evaluate their effects on fruit quality. The statistical was in a complete randomized block design, and the treatments were arranged in a factorial scheme (3 x 3) in subdivided splits, resulting in 9 treatments with tree replications, totaling 27 plots in the experimental area. In the horizontal plots the three doses of phosphorus fertilization (100, 150 and 300 kg.ha-1 of P2O5) were randomly allocated, and in the subplots the three potassium doses (50, 100 and 200 kg.ha-1 of K2O), were applied in fertirrigation. The cultivar used was Crimson Sweet. Seventy-Six days after planting (DAP) the biochemical characteristics of watermelon fruits were evaluated: total soluble solids (TSS), total treatable acidity (TTA) and potential of hydrogen (pH). According to the results, it was verified that only the chemical value of the TSS fruits, presented significant statistical differences between the studied doses because of the different source of fertilization K and P increased the soluble solid contents, the content of reducing sugars, and decreased pH. It was observed the different doses of K and P did not influence in the fruit quality parameters when it was analyzed separated: TTA and pH but the TTA values are according to consumer market standards. The best doses in order to economy of fertilizer were (150 kg ha-1 de P2O5 e 50 kg ha-1 of K2O)