A simple method for the serodiagnosis of human hydatid disease based on a protein A/colloidal dye conjugate

Although autoantibodies and autoantibody-producing B cells are crucial for the initiation of lupus nephritis, their precise role in the development of the nephritic lesions is incompletely understood. This article summarizes the results of recent work in our laboratory related to this area. They indicate that not all autoantibodies are pathogenic. Furthermore, among the pathogenic subset, individual immunoglobulins produce clearly distinguishable immune deposit patterns in specific glomerular locations and this is associated with different disease profiles (i.e., inflammation, proteinuria). The variation in immune deposit formation induced by the individual autoantibodies are reminiscent of the different lesions in lupus patients, and they appear to be related to differences in the reactivity of autoantibodies with specific glomerular antigens. Thus, it appears that the predominant interaction in a given individual influences the morphologic and clinical expression of disease. Autoantibody-producing B cells also influence the activation of autoreactive T cells that infiltrate the kidney to produce vasculitis and interstitial nephritis, and the potential mechanisms responsible for this phenomenon are discussed.     

One Step Lithography of Polypyrrole

Large areas of polypyrrole (PPy) thin films deposited onto inert polymeric substrates are structured by direct laser interference patterning (DLIP). Several square millimeter areas could be produced with one single (10 ns) pulse, at room temperature and atmospheric pressure. Nanometric arrays of lines (>600 nm) or grids of PPy deposited on dielectric polymers polypropilene or polypirrol (PP or PE) are fabricated by DLIP at 355 nm. The period of the lines structures, measured by white light interferometry (WLI), is 3.5 µm. Regular structures are analyzed using scanning electron microscope (SEM) and a focus ion beam (FIB) tomography. It is shown that only the PPy film is structured while the PP or PE substrate remains unaltered. Fourier transform infrared spectroscopy (FTIR) and UV‐vis spectroscopy, permit to ensure that PPy chemical structure remains unaltered after the structuration process. The width of PPy lines can be tailored by controlling the fluence of the laser beam. Contact angle measurement shows that the wettability is affected by the structuring, making the surface more hydrophobic. The structuring technique seems to be suitable for the fabrication of PPy regular structures over various substrates.     

Chemical ecology of the palm weevilRhynchophorus palmarum (L.) (Coleoptera: Curculionidae): Attraction to host plants and to a male-produced aggregation pheromone

Attraction to host plants by adultRhynchophorus palmarum (L.) palm weevils was studied in the field and in the laboratory. Chemical analysis revealed the presence of ethanol and ethyl-acetate in stems of coco palms and in pineapple fruits and of pentane, hexanal, and isopentanol in coco stems. In the olfactometer, the first two compounds and isoamyl-acetate were attractive to the insects and the last three compounds, although not attractive by themselves, increased attractiveness when mixed with the first two compounds. Mixtures of these compounds, in proportions similar to the one occurring in attractive plant tissue, were as attractive as natural coconut tissue. In the field, the chemical compounds, either presented alone or as a mixture, did not attract the weevil. Males produce an aggregation pheromone when smelling ethyl-acetate. Rhynchophorol, 2(E)-6-methyl-2-hepten-4-ol, the known active component of the aggregation pheromone, attracts weevils in the olfactometer and in the field only if plant tissue, ethyl-acetate, or the above-mentioned odor mix are present. We propose that a complex mix of ethanol, ethyl-acetate, pentane, hexanal, isolamyl-acetate, and/or isopentanol serve as a short-range orientation cue to fresh wounds on the plant and that additional host odors, attracting weevils from a distance, have still to be discovered. Rhynchophorol can be considered to be a Synergist, having an anemotactic action at a distance. We recommend the use of retention traps baited with rhynchophorol, ethyl-acetate, and sugar cane as an alternative control method for the pest.     

Technical properties of compounded kaolin sample from Griva (Macedonia, Greece)

The purpose of this paper is to establish the possible industrial applications of Griva kaolin. This kaolin comes from the alteration of gabbroic rocks from the Griva area, Macedonia, Greece. Mineralogically, the kaolin is composed mainly of kaolinite associated with vermiculite and plagioclases, and traces of quartz, amphiboles, halloysite and smectites. The kaolin grain-size analysis shows that the kaolin is mostly finer than <20 μm with 20% of <2 μm. The amounts of Fe, Mg and Ca for the < 20 μm fraction are higher than those of standard commercial kaolins. The kaolinite is disordered with low crystallinity. Kaolinite crystals do not present typical pseudohexagonal stackings, showing irregular morphology, and vermicular aggregates booklets. The Brookfield viscosity of about 450 cp (at 70% solids 12 rpm), the high brightness (83% on < 20 μm fraction) and the dispersability in water suspensions would favour its use as filler in the paper and paint industries. However, the low crystallinity kaolinite precludes its use as filler in rubber industry. The kaolin shows a liquid limit of about 48% and a plastic limit of 34%. The firing characteristics indicate its possible use as a ceramic raw material for stoneware and sanitary ware products.     

Box-counting algorithm on GPU and multi-core CPU: an OpenCL cross-platform study

In this paper, we present the analysis and development of a cross-platform OpenCL implementation of the box-counting algorithm, which is one of the most widely-used methods for estimating the Fractal Dimension. The Fractal Dimension is a relevant image analysis method used in several disciplines, but computing it is in general a time consuming process, especially when working with 3D images. Unlike parallel programming models that strictly depend on the hardware type and manufacturer, like CUDA, OpenCL allows us to provide an implementation suitable for execution on both GPUs and multi-core CPUs, whatever the hardware manufacturer. Sorting is a key part of the fast box-counting algorithm and the final speedup is highly conditioned by the efficiency of the sorting algorithm used. Our study reveals that current OpenCL implementations of sorting algorithms are clearly slower when compared with both CUDA for GPU and specific multi-core CPU implementations. Our OpenCL algorithm has been specifically optimized according the type of the target device and the results show an average speedup of up to 7.46× and 4×, when executed on the GPU and the multi-core CPU respectively, both compared with the single-threaded (sequential) CPU implementation.     

Point in solid test for free-form solids defined with triangular Bézier patches

A new algorithm to study the fundamental point in solid test for free-form solids is presented. The test is performed efficiently and robustly because it does not use trigonometric functions and it makes it unnecessary to deal with complex special cases. The algorithm is based on considering the solid as composed of original tetrahedra and free-form cells, and it computes the test in two stages: evaluation of the point inclusion in these simple elements and merging of the results in a simple sum. The solid boundary is defined as a set of low-degree triangular Bézier patches.     

Effect of chemical functionalization on the electrochemical properties of conducting polymers. Modification of polyaniline by diazonium ion coupling and subsequent reductive degradation

The electrochemical properties of polyaniline (PANI) can be altered by coupling the polymer with aryldiazonium ions. The ions are synthesized by diazotization of aromatic primary amines (1-aminoanthraquinone, sulphadiazine and 4-cyanoaniline) bearing functional groups which are then linked to the polyaniline backbone. All materials produced are electroactive, suggesting that the reaction involves coupling of the diazonium ion with the aromatic rings and not nucleophilic substitution by the aminic nitrogen of PANI on the aryl cations. The electrochemical properties of the modified polymers are different to those of PANI, likely due to electronic and steric effects of the attached groups. Reductive degradation of the azo linkages, using dithionite ion, removes the attached moieties leaving primary amino groups attached to the polyaniline backbone. In that way, the effect of the attached groups on the electrochemical properties of PANI is eliminated. FTIR spectroscopy measurement of the different polymers supports the proposed mechanism. Using the method a polymer containing redox (anthraquinone) groups, which could be used for charge storage, is obtained. Additionally a material containing sulphadiazine moieties, which can be released in vivo by bacterial activity, is also produced. The molecule is a well-known sulfa drug with bacteriostatic activity. The reaction sequence seems to be of general application to modify polyanilines, by attaching functional groups, and then to produce a PANI backbone bearing primary amino groups. Evidence is presented on the kinetic control of attached group removal.