Distribution of endogenous farnesyl pyrophosphate and four species of lysophosphatidic Acid in rodent brain

Lysophosphatidic acid (LPA) is the umbrella term for lipid signaling molecules that share structural homology and activate the family of LPA receptors. Farnesyl Pyrophosphate (FPP) is commonly known as an intermediate in the synthesis of steroid hormones; however, its function as a signaling lipid is beginning to be explored. FPP was recently shown to an activator of the G-protein coupled receptor 92 (also known as LPA5) of the calcium channel TRPV(3). The LPA receptors (including GPR92) are associated with the signal transduction of noxious stimuli, however, very little is known about the distribution of their signaling ligands (LPAs and FPP) in the brain. Here, using HPLC/MS/MS, we developed extraction and analytical methods for measuring levels of FPP and 4 species of LPA (palmitoyl, stearoyl, oleoyl and arachidonoyl-sn-glycerol-3 phosphate) in rodent brain. Relative distributions of each of the five compounds was significantly different across the brain suggesting divergent functionality for each as signaling molecules based on where and how much of each is being produced. Brainstem, midbrain, and thalamus contained the highest levels measured for each compound, though none in the same ratios while relatively small amounts were produced in cortex and cerebellum. These data provide a framework for investigations into functional relationships of these lipid ligands in specific brain areas, many of which are associated with the perception of pain.     

Utilization of hydrophilic/hydrophobic hyperbranched poly(amidoamine)s as additives for melamine urea formaldehyde adhesives

Hyperbranched poly(amidoamine)s (PAMAMs), exhibiting various levels of hydrophilicity, were used as modifiers for melamine urea formaldehyde (MUF) adhesives. The modification was achieved either with or at expense of sodium hydroxide during the last pH adjustment. Their apparent co‐condensability was expected from the measured gel times and further proved using Fourier transform infrared (FTIR) spectroscopy as well as ¹³C nuclear magnetic resonance (¹³C NMR). Utilization of these structures as modifiers for MUF, which are frequently used in particleboards production, resulted in manifold advantages. Considering the economic point of view, their use is more practical and cheaper with respect to dendritic structures. Additionally, their application in finite quantities as final additives, either immediately before the final use or at the last stage of preparation, yielded considerable upgrading of the dry internal bond (IB) strength of the produced particleboards. The improvement was extended to the resistivity to hydrolytic degradation as revealed by the wet IB strength and thickness swelling. The results were explained on the light of an extensive investigation on the resins using thermomechanical analysis (TMA) while taking into account the relevant hydrophilicity and degree of branching of each hyperbranched structure. POLYM. COMPOS., 36:2255–2264, 2015. © 2014 Society of Plastics Engineers     

Artificial neural network study of whole-cell bacterial bioreporter response determined using fluorescence flow cytometry

Genetically engineered bioreporters are an excellent complement to traditional methods of chemical analysis. The application of fluorescence flow cytometry to detection of bioreporter response enables rapid and efficient characterization of bacterial bioreporter population response on a single-cell basis. In the present study, intrapopulation response variability was used to obtain higher analytical sensitivity and precision. We have analyzed flow cytometric data for an arsenic-sensitive bacterial bioreporter using an artificial neural network-based adaptive clustering approach (a single-layer perceptron model). Results for this approach are far superior to other methods that we have applied to this fluorescent bioreporter (e.g., the arsenic detection limit is 0.01 microM, substantially lower than for other detection methods/algorithms). The approach is highly efficient computationally and can be implemented on a real-time basis, thus having potential for future development of high-throughput screening applications.     

Incorporation of magnetic nanoparticles into lamellar polystyrene-b-poly(n-butyl methacrylate) diblock copolymer films: Influence of the chain end-groups on nanostructuration

In this article, we present new samples of lamellar magnetic nanocomposites based on the self-assembly of a polystyrene-b-poly(n-butyl methacrylate) diblock copolymer synthesized by atom transfer radical polymerization. The polymer films were loaded with magnetic iron oxide nanoparticles covered with polystyrene chains grown by surface initiated-ATRP. The nanostructuration of the pure and magnetically loaded copolymer films on silicon was studied by atomic force microscopy, ellipsometry, neutron reflectivity and contact angle measurement. The present study highlights the strong influence of the copolymer extremity - driven itself by the choice of the ATRP chemical route - on the order of the repetition sequences of the blocks in the multi-lamellar films. In addition, a narrower distribution of the nanoparticles’ sizes was examined as a control parameter of the SI-ATRP reaction.     

Distribution of water in ceramic green bodies during drying

In order to investigate drying mechanisms at different stages, the distribution of water within the ceramic green bodies at different scales has been examined. The experimental measurements, using a simple weighing technique and Magnetic Resonance Imaging (MRI), show that during the first stage of drying involving shrinkage the material is constituted of uniquely solid and water with no gradient in water content within the sample. Then, during the second stage of drying, significant differences of water content as a function of position appear. As a complement, at the grain scale, observations using environmental scanning electron microscopy were made giving useful information on the solid–liquid–gas interfaces in the near surface part of the green body. Finally, the gradients in the water distribution were exploited to make a simple estimate of the diffusion coefficient of water with its dependence on the moisture content.     

Fourier Transform Domain Analysis of High <Emphasis Type="Italic">T</Emphasis><Subscript><Emphasis Type="Italic">c</Emphasis></Subscript> Superconducting Rectangular Microstrip Patch over Ground Plane with Rectangular Aperture

A rigorous full-wave analysis in the Fourier transform domain is carried out in order to obtain the resonant frequencies and half-power bandwidths of the high T _c superconducting rectangular microstrip patches over ground planes with rectangular apertures. To include the effect of the superconductivity of the microstrip patch in the full-wave analysis, a complex surface impedance is considered. This impedance is determined by using London’s equation and the two-fluid model of Gorter and Casimir. The validity of the solution is tested by comparison of the computed results with previously published data. Variations of the resonant frequency with the high T _c superconducting film thickness are presented. Results showing the effect of the temperature on the resonant frequency and half-power bandwidth of the superconducting microstrip antenna with a rectangular aperture in the ground plane are also given. Finally, a comparison between the efficiency of two antennas is presented. For the first antenna, YBCO patch with YBCO ground plane are considered. For the second antenna, the patch and the ground plane are with copper.     

Rheological and sensory characteristics of doughs and cookies based on wheat,soybean, chick pea and lupine flour

Levels of 5, 10 and 15% of legume flours i.e. soybean, lupine and chick pea were used to supplement cookie. The effect of this supplementation on the rheological properties of the resulting dough was investigated using farinograph and extensograph as objective methods for quality assessment of the final product. It was found that there was an increase in water absorption capacity, dough stability, arrival time, dough development time and mix tolerance index. Extensograph results indicated that dough resistance to extension, dough energy and proportional number were minimized with increasing the lupine flour in the formula, while it was not changed on dough extensibility. However, soy flour increased resistance to extension, proportional number and energy and diminished dough extensibility. At the same time supplementing wheat flour with chick peas decreased both dough resistance to extension and proportional number while it increased dough extensibility and energy. For sensory evaluation, it was found that using either until 5% soybean or 10% chick pea or 15% lupine flour could replace the wheat flour in cookies formula without adversely affecting baking performance or altering the physical characteristics of the end product.     

Spectral density variation mapping of cerebral waves by three‐dimensional interpolation techniques

This work focuses on interpolation methods which are proposed as solutions to the EEG source localization. First, a low pass and a high pass filter were applied to the EEG signal in order to remove EEG artifacts. Then, classical interpolation techniques such as three‐dimensional (3D) K‐nearest neighbor and 3D spline were implemented. The major contribution of this article is to develop a new interpolation method called 3D multiquadratic technique which is based on the Euclidean distances between the electrodes. A substitution of the Euclidean distance by the corresponding arc length was realized to promote the 3D spherical multiquadratic interpolation. Based on measured EEG recordings from 19 electrodes mounted on the scalp, these interpolation methods (3D K‐nearest neighbor, 3D spline, 3D multiquadratic and spherical multiquadratic) were applied to EEG recordings of 15 healthy subjects at rest and with closed eyes. The aim of EEG interpolation is to reach the maximum of the spatial resolution of EEG mapping by predicting the brain activity distribution of 109 virtual points located on the scalp surface. The evaluation of the different interpolation methods was achieved by measuring the means of the normalized root mean squared error (NRMSE) and processing time. The results showed that the multiquadratic and 3D spline interpolation methods gave the minimum normalized root mean squared error, but the multiquadratic method was characterized by the minimal processing time compared with 3D K‐nearest neighbor, 3D spline, and 3D spherical multiquadratic methods. Finally, a Spectral density variation mapping of different cerebral waves (delta, theta, alpha and beta) with 128 electrodes was generated by applying the Fast Fourier Transform (FFT). © 2015 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 25, 191–198, 2015