Vitamin D and Evening Primrose Oil Administration Improve Glycemia and Lipid Profiles in Women with Gestational Diabetes

Limited data are available assessing the effects of vitamin D and evening primrose oil (EPO) administration on markers of insulin resistance and lipid concentrations in gestational diabetes mellitus (GDM). This study was designed to evaluate the effects of vitamin D and EPO administration on insulin resistance and lipid concentrations among women with GDM. In this prospective randomized, double‐blind, placebo‐controlled clinical trial, 60 participants with GDM were divided into 2 groups of either 1000 IU vitamin D3 and 1000 mg EPO or placebo for 6 weeks. At the beginning and end of the study, fasting blood samples were obtained from the participants to measure related variables. After 6 weeks of intervention, changes in fasting plasma glucose (?3.6 ± 7.5 vs. +1.5 ± 11.4 mg/dL, P = 0.04), serum insulin concentrations (?2.0 ± 5.3 vs. +4.6 ± 10.7 µIU/mL, P = 0.004), homeostasis model of assessment (HOMA) insulin resistance (?0.5 ± 1.1 vs. +1.1 ± 2.5, P = 0.003), HOMA‐B cell function (?7.7 ± 23.3 vs. +17.4 ± 42.9, P = 0.007) and the quantitative insulin sensitivity check index (+0.01 ± 0.02 vs. ?0.01 ± 0.02, P = 0.007) in the vitamin D plus EPO group were significantly different from the placebo group. In addition, compared with the placebo, vitamin D and EPO supplementation resulted in significant reductions in serum TAG (?20.0 ± 54.3 vs. +34.3 ± 38.2 mg/dL, P < 0.001), VLDL (?4.0 ± 10.9 vs. +6.9 ± 7.6 mg/dL, P < 0.001), TC (?22.1 ± 32.6 vs. +5.3 ± 20.1 mg/dL, P < 0.001), LDL concentrations (?18.0 ± 25.5 vs. +1.8 ± 15.7 mg/dL, P = 0.001) and TC/HDL (?0.3 ± 0.4 vs. +0.3 ± 0.5 mg/dL, P < 0.001). We did not observe any significant effect of vitamin D and EPO supplementation on serum HDL concentrations. Clinical trial registration number: http://www.irct.ir : IRCT201509115623N52.     

Single‐constant simplification of Kubelka‐Munk turbid‐media theory for paint systems—A review

For opaque coloration systems, Kubelka‐Munk turbid media theory is used commonly to model optical mixing behavior. Most educational publications on the subject use opaque paint systems when describing the two‐constant approach and textile systems when describing the single‐constant simplification. Because of the differences in defining concentration for these systems and the corresponding degrees of freedom, the single‐constant simplification for paint and textile systems are not identical. The second edition of “Principles of Color Technology” showed a numerical example for an opaque paint system modeled using the textile equations. The third edition used the same example but modified the degrees of freedom, a hybrid of the paint and textile approaches. Recent research by Berns and Mohammadi has evaluated the single‐constant simplification for modeling artist paints; they have used both the hybrid and paint approaches. Thus, it was of interest to review these different approaches and determine whether these differences have practical importance and whether future printings and editions of Principles of Color Technology should be modified. The three approaches were tested for tints made from a mixture of cobalt blue and titanium white acrylic emulsion artist paints. The differences between the textile and hybrid approaches were inconsequential. The paint approach was superior and its use is recommended for opaque paint systems. The differences in the numerical example from Principles of Color Technology were very small. For future printings of the third edition, the example will remain unchanged. For future editions, including the numerical example remains an open question. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 201–207, 2007     

Non-transferred Arc Torch Simulation by a Non-equilibrium Plasma Laminar-to-Turbulent Flow Model

Non-transferred arc torches are at the core of diverse industrial applications, particularly plasma spray. The flow in these torches transitions from laminar inside the torch to turbulent in the emerging jet. The interaction of the plasma with the processing gas leads to significant deviations from local thermodynamic equilibrium (LTE) far from the arc core. The flow from a non-transferred arc plasma spray torch is simulated using a non-LTE (NLTE) plasma flow model solved by variational multiscale (VMS) and nonlinear VMS (VMS_n) methods, which are suitable for unified laminar and turbulent flow simulations. Non-plasma turbulent jet simulations indicate that the VMS_n method produces results comparable to those by the dynamic Smagorinsky method, often considered the workhorse for turbulent incompressible flow simulations. VMS and VMS_n approaches are applied to the simulation of incompressible, compressible, and NLTE plasma flows in non-transferred arc torch operating at representative conditions found in plasma spray processes. The NLTE plasma flow simulations reproduce the dynamics of the arc inside the torch together with the evolution of turbulence in the produced plasma jet in a cohesive manner. However, the similarity of results by both methods indicates the need for numerical resolution significantly higher than what is commonly afforded in arc torch simulations.     

Optimal design analysis of electrothermally driven microactuators

This paper explores a comparative study between different designs of electrothermal microactuators with emphasis on optimal design and performance key factors. For this purpose, two typical designs for electrothermal microactuators with the same material properties are studied: one with different beam lengths (design A), other one with different beam sections and a flexure part (design B). Analytical model and finite element model (FEM) have been developed and validated by comparison of simulation results with experimental results in literature. Optimal geometrical dimensions to achieve maximum deflection have been obtained using genetic algorithm (GA). As the key factors, temperature distribution, power consumption and deflection of these microactuators have been compared in the range of microactuator functionality. Design B is more sensitive to geometrical dimension variation. Using optimal geometrical dimensions, an increase of almost 40 and 55% has been achieved for design A and B tip deflections, respectively. The modified design A with a gold layer results to an increase of 70% for tip deflection comparing to its optimal design.     

Synthesis and characterization of nanowire-based anisotropic conductors

We investigated the potential of commercially available porous templates to be used for the fabrication of functional anisotropic conductors. A galvanostatic deposition technique was used to fabricate arrays consisting of 200 nm diameter nanowires inside the pores of polycarbonate membranes. A tape lift-off procedure allowed the complete removal of any residual metal from both sides of the polymer membrane to form an anisotropic conductive film. The 10 microm thick film has roughly 3 x 10(8) nanowires per cm2, and it showed near zero electrical resistance perpendicular to the surface while appearing completely open to circuits between any points on the surface. The preparation of the film, characterization using SEM, AFM, and resistance measurements are presented. The 1D conductivity of these membranes may have many potential applications for microelectronic interconnects for packaging technologies.     

Modeling the Rheological Behavior of Chemically Interesterified Blends of Palm Stearin/Canola Oil as a Function of Physicochemical Properties

The main aim of the current study was to model the rheological and textural properties of chemically interesterified palm stearin (PS)/canola oil (CO) blends as a function of saturated fatty acids (SFA), solid fat content (SFC), and temperature. The results and proposed models in this study can be used in design and development of new fat products by trying to limit the need for instrumental methods. To describe and predict how the viscoelastic properties and firmness of the blends change with SFA content, several models have been proposed. The firmness curves of fat samples were described as a function of (SFA, Firmness _f(SFA), Rsqr = 0.94, and mean absolute error (MAE) = 1009.00 g) and (SFC₂₀, Firmness _f(SFC20), Rsqr = 0.98, and MAE = 750.80 g) using a one-variable Quadratic model. In the next step, a two-variable Quadratic function for expression of firmness as a function of both SFA content and SFC₂₀ with high goodness of fit and low error (Rsqr = 1.00 and MAE = 0.00) was developed. The G′ modulus as a function of temperature (G′ _f(T)) and SFC (G' _f(SFC)) curves was S-shaped and the three Sigmoidal functions (Logistic, Gompertz, and Sigmoid models) were well able to describe their properties. However, the Logistic models described the G′ _f(T) (Rsqr>0.99 and MAE < 7838.00 Pa) and G′ _f(SFC) (Rsqr>0.94 and MAE < 20,802.00 Pa) curves in the best way. Finally, a two-variable Logistic model considering both temperature and SFC as variables was developed and fitted on the experimental data with Rsqr of 0.97 and MAE of 85,367.56 Pa. The validation of the proposed models shows their efficiency and ability for prediction of rheological and textural values of various interestrified blends.     

The use of biodegradable polymers for the stabilization of copper nanoparticles synthesized by chemical reduction method

Copper nanoparticles were synthesized by a convenient and rapid chemical reduction method in ambient condition using \(\hbox {Cu}(\hbox {NO}_{3})_{2}{\cdot } 3\hbox {H}_{2}\hbox {O}\) as a precursor, hydrazine hydrate as reducing agent and deionized water as solvent. The product was characterized by X-ray diffraction (XRD) patterns, field emission scanning electron microscopy, Fourier transform infrared spectroscopy and UV–Vis spectroscopy. However, agglomerated copper nanoparticles were obtained by this chemical reduction method. Hence, the effects of three polymers of polyvinyl pyrrolidone, polyethylene glycol (PEG) and starch as stabilizers on the size and size distribution of Cu nanoparticles were investigated. According to the results, smallest copper nanoparticles (30–50 nm) with a narrow size distribution were obtained using PEG as the stabilizing polymer. Zero-valent copper nanoparticles with high purity were obtained by this method and there was no peak related to the oxidized impurities such as CuO and \(\hbox {Cu}_{2}\hbox {O}\) in the XRD and UV–Vis studies, both in the presence and in the absence of stabilizer. On the other hand, by this method, zero-valent copper nanoparticles were obtained in the absence of any anti-oxidant agent and any inert gas flow. The effects of synthesis parameters including initial concentration of precursor, polymer concentration and the reaction temperature on the size and size distribution of copper nanoparticles were investigated using the UV–Vis analysis to determine the optimum synthesis conditions.     

Sol-gel assisted synthesis of TiB2-B4C composite powder

Composite powders containing titanium diboride and boron carbide have been prepared by sol-gel method at 1450°C using titanium isopropoxide (titanium precursor), boric acid (Boron precursor), sucrose (carbon source), and acetic acid (AcOH) as a solvent. The effect of boron source (trimethyl borate and boric acid) and B₂O₃/TiO₂, C/B₂O₃ mole ratios of starting materials on the final phases has been studied. The progress of reactions was determined using thermal analysis (TGA-DTA). The resultant powders were characterized by X-ray diffraction (XRD) analysis and field-emission scanning electron microscope (FESEM). XRD patterns confirmed the formation of TiB₂, B₄C, and TiC phases after heat treatment at 1450°C at mole ratio of B₂O₃/TiO₂ = 4.5, C/B₂O₃ = 2.4. With increasing the content of boron oxide, the unwanted phases such as TiC and C were reduced. TiB₂ and B₄C composite powders (~5 µm diameter) containing residual carbon (<4 wt%) were synthesized using the mole ratio of B₂O₃/TiO₂ = 10 and C/B₂O₃ = 1.9 at low temperature of 1450°C.     

Low-power high-speed phase frequency detector based on carbon nano-tube field effect transistors

A phase frequency detector (PFD) with a very low dead zone is proposed which is based on a configuration adaptable to both CMOS or carbon nano-tube transistors (CNTFETs). In the first step the proposed configuration is designed using CMOS transistors, and then CNTFETs are substituted to improve the speed and reduce the propagation delay. The proposed PFD in addition to very low dead zone, has low power consumption and high frequency range of operation, which are achieved as a result of the elimination of the reset path. The simulation results based on 32 nm technology for CNTFET and 180 nm technology for CMOS, illustrate that CNTFET-based proposed circuit dissipates 2 µW and has frequency of operation up to 30 GHz, and the dead zone equal to 1 ps. Compared to the conventional PFD based on CMOS technology, its dead zone and power consumption are lower. In addition, the effects of blocks’ parameters including the phase detector, which affect the operation of the phase locked loop, or delay locked loop, are systematically analyzed.

     

Analysis by mass spectrometry of the hydrolysis/condensation reaction of a trialkoxysilane in various dental monomer solutions

3‐Methacryloxypropyltrimethoxysilane (MPTMS) was converted to silsesquioxane oligomers by hydrolysis/condensation in three dental monomer solutions. The molecular mass distribution and molecular structures of these oligomers was studied by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. Each dental monomer imparted distinct characteristics on the oligomeric silsesquioxane produced. Ethoxylated bisphenol A dimethacrylate (EBPADMA) produced low‐mass oligomer silsesquioxanes that showed complete hydrolysis and a very high degree of intramolecular condensation (i.e., there were no methoxy and few silanol groups remaining on the oligomers). 1,6‐Bis(methacryloxy‐2‐ethoxycarbonylamino) 2,4,4‐trimethylhexane also produced fully hydrolyzed oligomeric silsesquioxanes but with twice the average molecular mass as the EBPADMA. Finally, triethylene glycol dimethacrylate produced higher mass oligomeric silsesquioxanes than EBPADMA even though it showed incomplete hydrolysis. The degree of hydrolysis increased with increasing mass, as did the degree of intramolecular condensation. Oligomers with degrees of polymerization below 8 were poorly hydrolyzed and showed little if any intramolecular condensation. Those with degrees of polymerization of 9 or greater were almost completely hydrolyzed with a high level of intramolecular condensation. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1842–1847, 2006