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Fiber orientation distribution estimation with diffusion magnetic resonance imaging (dMRI) is critical in white matter fiber tractography which is most commonly based on symmetric crossing structures. Ambiguous spatial correspondence between estimated diffusion directions and fiber geometry, such as asymmetric crossing, bending, fanning, or kissing, makes tractography challenging. Consequently, numerous tracts suggest intertwined connections in unexpected regions of the white matter or actually stop prematurely in the white matter. In this work, we propose a novel asymmetric fiber trajectory distribution (FTD) function defined on neighboring voxels based on a streamline differential equation from fluid mechanics. The spatial consistency with intra- and inter-voxel constraints is derived for FTD estimation by introducing the concept of divergence. At a local level, the FTD is a series of curve flows that minimize the energy function, characterizes the relations between fibers and joint fiber fragments within the same fiber bundle. Experiments are performed on FiberCup phantom, ISMRM 2015 Tractography challenge data, and in vivo brain dMRI data for qualitative and quantitative evaluations. Results show that our approach can reveal continuous asymmetric FTD details that are potentially useful for robust tractography. In this study, a green switchable solvent based liquid phase extraction (SS-LPE) method was developed for the determination of iron in human hair matrix at very low concentrations. The switchable solvent was synthesized from N,N-Dimethlybenzylamide (DMBA) and ultrapure water with the addition of dry ice for protonation, and used as the extraction solvent. The optimum conditions obtained for 8.0 mL aqueous solution after univariate optimization were 1.5 mL of pH 4.0 buffer solution, 0.75 mL of 0.015 % ligand solution, 0.75 mL of switchable solvent, 45 s vortex period for complexation and extraction, 1.25 mL of 1.50 M NaOH and 30 s vortex period after the addition of NaOH. Under the optimum conditions, a 92-fold improvement was obtained in the detection power of the flame atomic absorption spectrometry (FAAS). The limit of detection (LOD) and limit of quantification (LOQ) values were found to be 2.6 and 8.6 μg/L, respectively. Linear range of the developed method was between 11 and 75 μg/L, with a correlation coefficient (R2) value of 0.9992. Accuracy and the applicability of the proposed method were verified by recovery studies and the results obtained for 15, 20, 30 and 40 μg/L spiked concentrations were 113.3 ± 4.9, 90.6 ± 4.4, 102.8 ± 8.2 and 98.1 ± 7.5 %, respectively. Oxylipins are a family of saturated and unsaturated fatty acids peroxidation products with bioactive properties. We have developed an improved method for the measurement of ex vivo oxylipin production by peripheral blood mononuclear cells (PBMCs) and neutrophils. We aimed to develop an analytical method to determine the production rates of polyunsaturated fatty acids (PUFAs), PUFA-oxylipin, and saturated-oxylipins by stimulated PBMCs and neutrophils based on solid phase extraction and HPLC-MS/MS technology. A UHPLC system coupled to a Q-Exactive Hybrid Quadrupole-Orbitrap mass spectrometer was used to identify and quantify oxylipin production. Voruciclib price For each oxylipin and PUFA their differential response was calculated with respect to a deuterated internal standard factor (ISF). To calculate oxylipin and PUFAs in the culture samples, the individual ISF was used for each oxylipin and PUFA with respect to the deuterated internal standard. PBMCs and neutrophils showed a different pattern of oxylipin production and fatty acid secretion. Lipopolysaccharide (LPS) did not stimulate oxylipin production or fatty acids secretion in PBMCs, whereas phorbol myristate acetate (PMA) stimulation increased the production rate of 5-HETE, 15-HETE, 15-HEPE, 17-DoHE, PGE2, AA, and DHA. LPS stimulation decreased 16-hydroxyl-palmitatte (16-OHPAL) production and DHA secretion in neutrophils, while PMA stimulation increased the production rate of AA and its derivate oxylipins, 5-HETE, 15-HETE, and PGE2. In conclusion, we have developed a new method to determine oxylipins derived from both saturated and unsaturated fatty acids in culture cell media. This method has enough sensitivity, and accuracy, to determine oxylipin production and fatty acid secretion by PBMCs and neutrophils. V.The potential of solid olive wastes-based adsorbent (CuO-OC) with photocatalytic power was established for the removal of total phenolics and photocatalytic discolourization of high strength olive mill wastewater (OMW). Clear insight of the FTIR and Brunauer-Emmett-Teller analyses showed that oxygen-containing functional groups of CuO-OC likely participated in the adsorption of total phenols from the OMW via a π-π interaction, hydrogen bonding and electrostatic interaction. Also, the total pore volume of CuO-OC decreased from 0.068 to 0.052 cm3 g-1 after adsorption, which suggested that phenolics were trapped within the micro- and mesopores of CuO-OC. The adsorption kinetics revealed that ∼82.7-95% of the phenolic compounds were removed within the first 360 min which is relatively faster than adsorbents and methods reported elsewhere. The isotherm results showed that Redlich-Peterson equation fit the experimental data very well with least error (χ2 = 1.46-3.19) and high correlation coefficients (0.992-0.996), which suggested a mixture of hetero- and monolayer coverage of the phenolics on the CuO-OC surface. Results obtained herein are of practical interest and the reuse efficiency of CuO-OC remained ∼60% after 5 successive recycling. Low redox potential in flooded soils may affect phosphate bioavailability by reducing iron oxides or formation of new minerals. To investigate phosphate behavior in anoxic conditions, goethite was selected as a soil model and coated by humic acid (HA) and sodium borohydride was used as a reducing agent. Adsorption experiments were conducted in 0.1 M NaNO3 as a function of pH in oxic (Eh = +254 to +448 mV) and suboxic (Eh = -162 to +167 mV) conditions for four phosphate concentrations (0.05-0.8 mM). CD-MUSIC and NOM-CD models in combination with Extended Stern model were used to describe the experimental data. Results show that by increasing pH and carbon content in the organo-mineral composites, the released phosphate to the solution increases in both oxic and suboxic conditions. In suboxic conditions, as a result of sodium borohydride dissociation in water and consequently boron release to the solution, at high loading of boron and low loading of phosphate, boron can compete with phosphate for the surface reactive sites and decrease its adsorption.