mfERG_LAB: Software for processing multifocal electroretinography signals

The multifocal electroretinography technique consists of performing sectorized light excitation of the retina and capturing the resulting evoked potential. This provides functional localized information about the state of the retinal neurons. Analysis of multifocal electroretinography signals can be used for diagnosing different types of optic neuropathies (glaucomatous, demyelinating and ischemic ethiology). In order to obtain a reliable diagnosis, it is necessary to apply advanced processing algorithms (morphological, frequency and time-frequency analysis, etc.) to the multifocal electroretinography signal. This paper presents a software application developed in MATLAB(?) (MathWorks Inc., MA) designed to perform advanced multifocal electroretinography signal analysis and classification. This intuitive application, mfERG_LAB, is used to plot the signals, apply various algorithms to them and present the data in an appropriate format. The application's computational power and modular structure make it suitable for use in clinical settings as a powerful and innovative diagnostic tool, as well as in research and teaching settings as a means of assessing new algorithms.     

Overall performance measurement in a supply chain: towards a supplier-prime manufacturer based model

This study deals with the supply chain (SC) overall performance expression. The developed idea concerns more particularly the performance of the manufactured products. Indeed, two companies or more contribute to the manufacturing of products that are generally assembled by the prime manufacturer company. Moreover, in the industrial practice, performance scorecards are defined with regard to each process; and the overall performance is neither expressed for each company, nor for the whole SC. We propose here to identify the SC overall performance to the combination of the performances of the different involved companies in the SC. Thus, in order to obtain a definition of such performance, we choose to focus first on the performance of the prime manufacturer. In this sense, the approach is based on the SCOR model for the handling of the main processes around the considered product manufacturing. The prime manufacturer performance is then defined as the aggregation of its involved processes?? performances. While the prime manufacturer performance is strongly dependent on the suppliers?? performance, we suggest the integration of the impacting supplier performance into the prime manufacturer scorecards. From an operational point of view, the MACBETH methodology is used to coherently express both processes and overall performances. More precisely, the Choquet aggregation integral operator is applied in order to model mutual interactions between processes. Finally, the expression of a bearing??s manufacturer performance illustrates the proposition.     

Cristallogenese du 4-dimethylamino β-nitrostyrene

Single crystals of 4-dimethylamino β-nitrostyrene (DMNS) were grown from solution by a falling temperature technique. Growth conditions are given. The quality of crystals obtained was studied by X-ray diffraction methods.

$\text{DMNS : orthorhombic - class mmm - space group : Pcab}\text{a : b : c = 7,3 : 10,15 : 25,10}\text{A}\text{?}\text{Z=8}$

     

Complete structure of glycopeptides isolated from IgG immunoglobulins of cow colostrum

Bovine immunoglobulins (IgG1 type) have been isolated from colostral whey. Hydrolysis by pronase, trypsin and (or) chymotrypsin yield several glycopeptides structural studies of which lead to the following results. 1. IgG1 colostral immunoglobulins possess two glycan moieties which are linked to the peptidic chain by an N-(beta-aspartyl)-N-acetylglucosaminylamine bound. 2. The peptidic sequence around the linkage region has been determined by classical methods and is as follows: Thr-Lys-Pro-Arg-Glu-Glu-Gln-Phe-Asn(Glycan)-Ser-Thr-Tyr-Arg. 3. The following procedures: partial acidic hydrolysis, periodic oxidation, hydrazinolysis-nitrous deamination, methylation and use of specific glycosidases allowed us to determine the structure of the glycan moieties which fit with the general following scheme: (see article) Thus they could be related to the general glycan structure so-called of "N-acetyllactosamine type" because they possess the pentasaccharidic core common to numerous glycoproteins Man alpha 1 leads to [Man alpha 1 leads to 6] Man beta 1 leads to 4 GlcNAc beta 1 leads to 4 GlcNAc beta 1 leads to Asn on which are conjugated 2 N-acetyllactosamine residues. Besides they present a microheterogeneity which is due to the varying number of additional N-acetylneuraminic acid and fucose residues. 4. These structures are compared to various immunoglobulin structures proposed by others: bovine serum IgG and human serum IgG, IgE and IgA.     

Substrate temperature and water vapour effects on structural and mechanical properties of TiO x N y coatings

Dc reactive sputtering was successfully implemented to deposit titanium oxynitride thin films using a titanium metallic target, argon, nitrogen and water vapour as reactive gases. The nitrogen partial pressure was kept constant during every deposition whereas that of the water vapour was systematically changed from 0 to 0.1 Pa. The study aims at comparing the structural and mechanical properties of the coatings deposited at room temperature (293 K) and at 673 K. Surface morphology of the film was examined by atomic force microscopy and showed different aspects according to the growth temperature. Topography mainly depends on the amount of water vapour introduced during the deposition process. Some significant changes of the crystallographic structure, due to the high substrate temperature were correlated with the evolution of the surface aspect and roughness parameters. Determination of the phase occurrence by X-ray diffraction was also carried out and appeared to be a significant parameter in understanding the evolution of mechanical properties like nanohardness (H _n) and Young’s modulus (E). H _n and E values obtained by nanoindentation ranged from 16.5 to 7 GPa and from 240 to 100 GPa, respectively. For both temperatures, mechanical properties of titanium oxynitride thin films were notably reduced as a function of the water vapour supply, especially for partial pressures higher than 4 × 10⁻² Pa. These mechanical behaviours were correlated and discussed with the phase occurrence and the amorphous structure of titanium oxynitride thin films.     

Synthesis and characterization of coprecipitation-derived ferrimagnetic glass-ceramic

Ferrimagnetic glass-ceramics could be used for magnetic induction hyperthermia. This technique is utilised for the destruction of solid neoplastic diseases by application of an alternating magnetic field. Biocompatible ferrimagnetic materials could be easily incorporated into a tumour and could generate heat mainly by hysteresis loss. A ferrimagnetic glass-ceramic in the system SiO₂–Na₂O–CaO–P₂O₅–FeO–Fe₂O₃ has been prepared by melting of the coprecipitation-derived raw materials. This glass-ceramic contains a unique crystalline phase, magnetite, embedded in an amorphous matrix. Magnetite crystals precipitate during cooling from melting temperature. This glass-ceramic would no longer require any nucleation and growth thermal treatment, since the maximal quantity of magnetite crystals was produced during cooling. The average unit-cell parameter, crystallite size of magnetite, and the quantitative ratio of the crystallographic phases in the glass-ceramic samples were evaluated using two different methods. Similar results were obtained with both methods. The magnetite crystals are about 50 nm in dimensions. The samples contain 45 wt% of magnetite, homogeneously distributed in the amorphous residual matrix. The as prepared glass-ceramic has a saturation magnetisation of 34 A·m²/kg and a coercive force of 6.7 kA/m. The estimated magnetic loss/cycle under the magnetic field up to 796 kA/m is around 1.45 mJ/g. The specific power loss of this glass-ceramic under a magnetic field of 40 kA/m and a frequency of 440 kHz is 25 W/g. This material showed a bioactive behaviour, as after 2 weeks of soaking in a simulated body fluid the formation of a hydroxylapatite layer on their surface was observed. This feature makes it also suitable for bone cancer.     

IDR/UPM facilities for liquid bridge experimentation on Earth under microgravity conditions

Besides space laboratories for in-orbit experimentation, Earth based facilities for laboratory experimentation are of paramount importance for the enhancement on liquid bridge knowledge. In spite of the constraints imposed by simulated microgravity (which force to work either with very small size liquid bridges or by using the Plateau tank technique, amongst other techniques), the availability and accessibility of Earth facilities can circumvent in many cases the drawbacks associated with simulated microgravity conditions. To support theoretical and in orbit experimental studies on liquid bridges under reduced gravity conditions, several ground facilities were developed at IDR. In the following these ground facilities are briefly described, and main results obtained by using them are cited.     

Ultrasonic measurements of microelectronic resins

The elastic moduli, measured with the ultrasonic technique, of commercial silica filled epoxy resins used in the electronic circuits are reported. Measurements of velocity propagation and attenuation were carried out in large temperature and frequency ranges. Predictions of the theoretical models were compared with the experimental values. Explicit expressions of the elastic moduli were derived as functions of filler content and the properties of the matrix and the fillers. The influences of frequency and temperature on the elastic moduli and attenuation are discussed.     

10th GAMM-IMACS International Symposium on Scientific Computing,Computer Arithmetic,and Validated Numerics SCAN'2002

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