Non‐Fourier Boundary Conditions Effects on the Skin Tissue Temperature Response

Thermal wave and dual phase lag bioheat transfer equations are solved analytically in the skin tissue exposed to oscillatory and constant surface heat flux. Comparison between the application of Fourier and non‐Fourier boundary conditions on the skin tissue temperature distributions is studied. The amplitude of temperature responses increases and also the phase shift between the temperature responses and heat flux decreases under the non‐Fourier boundary conditions for the case of an oscillatory surface heat flux. It is supposed the stable temperature cycles in order to estimate the blood perfusion rate via the existing phase shift between the surface heat fluxes and the temperature responses. It is shown that the higher rates of the blood perfusion correspond to lower phase shift between the surface temperature responses and the imposed heat flux.     

Efficient synthesis of novel bis(arylmethylidenes) of the 2,2-dimethyl-1,3-dithian-5-one system

In a mixture consisting of catalytic quantities of diethylamine, sodium dodecyl sulfate, and a zirconium salt in water, 2,2-dimethyl-1,3-dithian-5-one undergoes double aldol condensation with two folds of aromatic aldehydes at 50^oC to yield the respective bisarylmethylidene derivatives efficiently within 2?h. The products precipitate in the reaction mixtures spontaneously, perhaps due to high polarity of the medium, avoiding time-consuming and expensive chromatographic separations. Thus, products are isolated easily by a simple filtration and recrystallization from ethyl acetate, while the filtrate was recycled successfully for subsequent reactions.     

Combinatorial Delivery of miRNA‐Nanoparticle Conjugates in Human Adipose Stem Cells for Amplified Osteogenesis

It is becoming more apparent in tissue engineering applications that fine temporal control of multiple therapeutics is desirable to modulate progenitor cell fate and function. Herein, the independent temporal control of the co‐delivery of miR‐148b and miR‐21 mimic plasmonic nanoparticle conjugates to induce osteogenic differentiation of human adipose stem cells (hASCs), in a de novo fashion, is described. By applying a thermally labile retro‐Diels–Alder caging and linkage chemistry, these miRNAs can be triggered to de‐cage serially with discrete control of activation times. The method relies on illumination of the nanoparticles at their resonant wavelengths to generate sufficient local heating and trigger the untethering of the Diels–Alder cycloadduct. Characterization of the photothermal release using fluorophore‐tagged miRNA mimics in vitro is carried out with fluorescence measurements, second harmonic generation, and confocal imaging. Osteogenesis of hASCs from the sequential co‐delivery of miR‐21 and miR‐148b mimics is assessed using xylenol orange and alizarin red staining of deposited minerals, and quantitative polymerase chain reaction for gene expression of osteogenic markers. The results demonstrate that sequential miRNA mimic activation results in upregulation of osteogenic markers and mineralization relative to miR‐148b alone, and co‐activation of miR‐148b and miR‐21 at the same time.     

A Least-Squares-Based Immersed Boundary Approach for Complex Boundaries in the Lattice Boltzmann Method

A least-squares algorithm for handling complex boundaries with the lattice Boltzmann method is proposed. The method is an extension to an immersed boundary implementation of the solver. We impose additional rules that are designed to conserve the mass flux through cut-cell control volumes and also to satisfy the continuity condition on the numerical boundary points. Then, we use the least-squares method to find the best achievable solution of the overdetermined system. Further, computational cost assessments are considered. The qualitative and quantitative results show that the velocity values obtained from simulation of a flow with curved and moving boundaries, i.e., the Taylor-Couette flow, are closer to the exact solution than the values found from the traditional approach. Finally, we present some statistical analysis to show that the velocities are obtained confidently.     

Allele frequency distribution for D11S1304, D11S1998, and D11S934 and metabolic syndrome in TLGS

Different variant frequencies may lead to different frequencies of the same variants in individuals with drugs resistance and disease susceptibility at the population level. In this study, the allele frequency of three STRs loci including D11S1304, D11S1998, and D11S934 was analyzed on a representative sample of 563 individuals from the capital city of Tehran. The sample included four different ethnic groups. In this sample, 130 individuals were affected with metabolic syndrome (Mets). Calculated parameters on the whole sample were: allele frequency, polymorphic information content values, observed and expected heterozygosity, discrimination power, matching probability, power of discrimination, power of exclusion, and paternity index. For all markers, no significant deviation from Hardy–Weinberg equilibrium was found in observed allele frequencies except D11S1998. There were no significant differences in the allele frequencies in short, medium and long alleles between the metabolic affected subjects and controls. The most significant findings of this study report allele frequency of some STRs on chromosome 11 for the first time in Iran and the observed differences between subjects affected with Mets as opposed to subjects in the control group.     

Analysis of the Applicability of the Lattice Boltzmann Method in Targeting a Chaotic Flame Front Model

In this paper, we present utilization of the lattice Boltzmann method (LBM) to analyze spatiotemporal chaotic fields. To this end, the one-dimensional Kuramoto–Sivashinsky equation, which is a proper model for unstable flame front flutter, is rewritten in terms of lattice Boltzmann equation components and is then solved. After accuracy checks, we alter the computational domain size and also the control parameter of the problem, which is representative of the kinematic viscosity in real flows, to capture the symmetry-breaking phenomenon. In the next step, since the method is in fact a one-dimensional explicit mapping for the probability density functions, we adopt the targeting algorithm of chaotic fields using LBM. The results show that the method can be applied to chaotic fields with confidence.     

Improved multiplex PCR assay for simultaneous detection of Bacillus cereus emetic and enterotoxic strains

Toxin producing Bacillus cereus can cause enterotoxic and/or emetic food poisoning. In the present study, a multiplex PCR assay was developed to detect all toxin genes known to be involved in food poisoning of B. cereus in a single reaction. Specific primers for the detection of enterotoxic (entFM, hblC, nheA, and cytK) genes and emetic toxin production (2 primer pairs: ces, CER) were designed based on the GeneBank sequences. The developed multiplex PCR assay was evaluated in pure culture and artificially inoculated milk, using 43 B. cereus strains and non-target strains. In brief, sensitivity in pure culture was 10-fold or more higher than artificially inoculated milk in multiplex PCR detection limit assay. The presented PCR assay is a developed molecular tool for the rapid simultaneous detection of emetic and enterotoxin producing B. cereus strains.     

Thermodynamic modeling of CO2 solubility in ionic liquid ([C n -mim] [Tf2N]; n=2, 4, 6, 8) with using Wong-Sandler mixing rule, Peng-Rabinson equation of state (EOS) and differential evolution (DE) method

Environmental and safety regulations are creating increasing interest in ionic liquids which have been used as alternative solvents for a wide range of industrial applications. Knowing the phase equilibrium of these materials is very important. In this study, the solubility of CO₂ in ionic liquid 1-alkyl-3 methylimidazolium bis (trifluoromethylsulfonyl) imide ([C _n -mim][Tf₂N]; n=2, 4, 6, 8) was probed with the Peng-Robinson (PR) equation of state (EOS) and Wong-Sandler mixing rule and van Laar model for excess Gibbs free energy. The differential evolution (DE) optimization method was applied to optimize the binary interaction parameter and activity coefficients. Moreover, binary interaction parameters and activity coefficients were presented as mathematical correlations that for various materials have depended on temperature. Our results showed that average absolute derivations of our proposed model were less than other existing models, and by using the aforesaid method better prediction could be achieved.     

A comparative study of two H2‐redistribution strategies along the FT reactor using H2‐permselective membrane

In this study, a comparative study of two different hydrogen redistribution strategies along the Fischer‐Tropsch synthesis reactor using a Pd‐Ag membrane has been carried out. In the first strategy, fresh synthesis gas is flowing in the tube side in co‐current mode with reacting material in shell side so that the first segments of reactor use more hydrogen. In the second strategy, fresh synthesis gas is flowing in the tube side in counter‐current mode with reacting material in shell side so that last segments of reactor use more hydrogen. A one‐dimensional heterogeneous model was developed to compare two strategies from different standpoints. The model was checked using operating data of Fischer‐Tropsch synthesis reactor in pilot plant of Research Institute of Petroleum Industry in Iran. Simulation results show an enhancement in the yield of gasoline production, a decrease in undesired products formation (CO₃ and CH₄) and also a favorable temperature profile along both the configurations of membrane Fischer‐Tropsch reactor in comparison with conventional reactor. The comparison between co‐current and counter‐current configurations in terms of temperature, gasoline (C) and CO₂ yields, H₂ and CO conversions, and selectivity of components shows the reactor in the co‐current configuration operates with lower reactants' conversions and also lower permeation rate of hydrogen. On the contrary, our results demonstrated counter‐current‐mode decrease CO₂ and CH₄ as undesired products, better than other kinds of mentioned systems. Copyright © 2010 John Wiley & Sons, Ltd.